1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/stat.h>
18 #include <sys/queue.h>
19 
20 #include <dirent.h>
21 #include <limits.h>
22 #include <stddef.h>
23 #include <string.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <time.h>
27 #include <fcntl.h>
28 #include <errno.h>
29 #include <unistd.h>
30 #include <zlib.h>
31 #include <fnmatch.h>
32 #include <libgen.h>
33 
34 #include "got_compat.h"
35 
36 #include "got_error.h"
37 #include "got_repository.h"
38 #include "got_reference.h"
39 #include "got_object.h"
40 #include "got_path.h"
41 #include "got_cancel.h"
42 #include "got_worktree.h"
43 #include "got_opentemp.h"
44 #include "got_diff.h"
45 
46 #include "got_lib_worktree.h"
47 #include "got_lib_sha1.h"
48 #include "got_lib_fileindex.h"
49 #include "got_lib_inflate.h"
50 #include "got_lib_delta.h"
51 #include "got_lib_object.h"
52 #include "got_lib_object_parse.h"
53 #include "got_lib_object_create.h"
54 #include "got_lib_object_idset.h"
55 #include "got_lib_diff.h"
56 #include "got_lib_gotconfig.h"
57 
58 #ifndef MIN
59 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
60 #endif
61 
62 #define GOT_MERGE_LABEL_MERGED	"merged change"
63 #define GOT_MERGE_LABEL_BASE	"3-way merge base"
64 
65 static mode_t		 apply_umask(mode_t);
66 
67 static const struct got_error *
68 create_meta_file(const char *path_got, const char *name, const char *content)
69 {
70 	const struct got_error *err = NULL;
71 	char *path;
72 
73 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
74 		return got_error_from_errno("asprintf");
75 
76 	err = got_path_create_file(path, content);
77 	free(path);
78 	return err;
79 }
80 
81 static const struct got_error *
82 update_meta_file(const char *path_got, const char *name, const char *content)
83 {
84 	const struct got_error *err = NULL;
85 	FILE *tmpfile = NULL;
86 	char *tmppath = NULL;
87 	char *path = NULL;
88 
89 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
90 		err = got_error_from_errno("asprintf");
91 		path = NULL;
92 		goto done;
93 	}
94 
95 	err = got_opentemp_named(&tmppath, &tmpfile, path, "");
96 	if (err)
97 		goto done;
98 
99 	if (content) {
100 		int len = fprintf(tmpfile, "%s\n", content);
101 		if (len != strlen(content) + 1) {
102 			err = got_error_from_errno2("fprintf", tmppath);
103 			goto done;
104 		}
105 	}
106 
107 	if (rename(tmppath, path) != 0) {
108 		err = got_error_from_errno3("rename", tmppath, path);
109 		unlink(tmppath);
110 		goto done;
111 	}
112 
113 done:
114 	if (fclose(tmpfile) == EOF && err == NULL)
115 		err = got_error_from_errno2("fclose", tmppath);
116 	free(tmppath);
117 	return err;
118 }
119 
120 static const struct got_error *
121 write_head_ref(const char *path_got, struct got_reference *head_ref)
122 {
123 	const struct got_error *err = NULL;
124 	char *refstr = NULL;
125 
126 	if (got_ref_is_symbolic(head_ref)) {
127 		refstr = got_ref_to_str(head_ref);
128 		if (refstr == NULL)
129 			return got_error_from_errno("got_ref_to_str");
130 	} else {
131 		refstr = strdup(got_ref_get_name(head_ref));
132 		if (refstr == NULL)
133 			return got_error_from_errno("strdup");
134 	}
135 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
136 	free(refstr);
137 	return err;
138 }
139 
140 const struct got_error *
141 got_worktree_init(const char *path, struct got_reference *head_ref,
142     const char *prefix, struct got_repository *repo)
143 {
144 	const struct got_error *err = NULL;
145 	struct got_object_id *commit_id = NULL;
146 	uuid_t uuid;
147 	uint32_t uuid_status;
148 	int obj_type;
149 	char *path_got = NULL;
150 	char *formatstr = NULL;
151 	char *absprefix = NULL;
152 	char *basestr = NULL;
153 	char *uuidstr = NULL;
154 
155 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
156 		err = got_error(GOT_ERR_WORKTREE_REPO);
157 		goto done;
158 	}
159 
160 	err = got_ref_resolve(&commit_id, repo, head_ref);
161 	if (err)
162 		return err;
163 	err = got_object_get_type(&obj_type, repo, commit_id);
164 	if (err)
165 		return err;
166 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
167 		return got_error(GOT_ERR_OBJ_TYPE);
168 
169 	if (!got_path_is_absolute(prefix)) {
170 		if (asprintf(&absprefix, "/%s", prefix) == -1)
171 			return got_error_from_errno("asprintf");
172 	}
173 
174 	/* Create top-level directory (may already exist). */
175 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
176 		err = got_error_from_errno2("mkdir", path);
177 		goto done;
178 	}
179 
180 	/* Create .got directory (may already exist). */
181 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
182 		err = got_error_from_errno("asprintf");
183 		goto done;
184 	}
185 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
186 		err = got_error_from_errno2("mkdir", path_got);
187 		goto done;
188 	}
189 
190 	/* Create an empty lock file. */
191 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
192 	if (err)
193 		goto done;
194 
195 	/* Create an empty file index. */
196 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
197 	if (err)
198 		goto done;
199 
200 	/* Write the HEAD reference. */
201 	err = write_head_ref(path_got, head_ref);
202 	if (err)
203 		goto done;
204 
205 	/* Record our base commit. */
206 	err = got_object_id_str(&basestr, commit_id);
207 	if (err)
208 		goto done;
209 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
210 	if (err)
211 		goto done;
212 
213 	/* Store path to repository. */
214 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
215 	    got_repo_get_path(repo));
216 	if (err)
217 		goto done;
218 
219 	/* Store in-repository path prefix. */
220 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
221 	    absprefix ? absprefix : prefix);
222 	if (err)
223 		goto done;
224 
225 	/* Generate UUID. */
226 	uuid_create(&uuid, &uuid_status);
227 	if (uuid_status != uuid_s_ok) {
228 		err = got_error_uuid(uuid_status, "uuid_create");
229 		goto done;
230 	}
231 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
232 	if (uuid_status != uuid_s_ok) {
233 		err = got_error_uuid(uuid_status, "uuid_to_string");
234 		goto done;
235 	}
236 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
237 	if (err)
238 		goto done;
239 
240 	/* Stamp work tree with format file. */
241 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
242 		err = got_error_from_errno("asprintf");
243 		goto done;
244 	}
245 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
246 	if (err)
247 		goto done;
248 
249 done:
250 	free(commit_id);
251 	free(path_got);
252 	free(formatstr);
253 	free(absprefix);
254 	free(basestr);
255 	free(uuidstr);
256 	return err;
257 }
258 
259 const struct got_error *
260 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
261     const char *path_prefix)
262 {
263 	char *absprefix = NULL;
264 
265 	if (!got_path_is_absolute(path_prefix)) {
266 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
267 			return got_error_from_errno("asprintf");
268 	}
269 	*match = (strcmp(absprefix ? absprefix : path_prefix,
270 	    worktree->path_prefix) == 0);
271 	free(absprefix);
272 	return NULL;
273 }
274 
275 const char *
276 got_worktree_get_head_ref_name(struct got_worktree *worktree)
277 {
278 	return worktree->head_ref_name;
279 }
280 
281 const struct got_error *
282 got_worktree_set_head_ref(struct got_worktree *worktree,
283     struct got_reference *head_ref)
284 {
285 	const struct got_error *err = NULL;
286 	char *path_got = NULL, *head_ref_name = NULL;
287 
288 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
289 	    GOT_WORKTREE_GOT_DIR) == -1) {
290 		err = got_error_from_errno("asprintf");
291 		path_got = NULL;
292 		goto done;
293 	}
294 
295 	head_ref_name = strdup(got_ref_get_name(head_ref));
296 	if (head_ref_name == NULL) {
297 		err = got_error_from_errno("strdup");
298 		goto done;
299 	}
300 
301 	err = write_head_ref(path_got, head_ref);
302 	if (err)
303 		goto done;
304 
305 	free(worktree->head_ref_name);
306 	worktree->head_ref_name = head_ref_name;
307 done:
308 	free(path_got);
309 	if (err)
310 		free(head_ref_name);
311 	return err;
312 }
313 
314 struct got_object_id *
315 got_worktree_get_base_commit_id(struct got_worktree *worktree)
316 {
317 	return worktree->base_commit_id;
318 }
319 
320 const struct got_error *
321 got_worktree_set_base_commit_id(struct got_worktree *worktree,
322     struct got_repository *repo, struct got_object_id *commit_id)
323 {
324 	const struct got_error *err;
325 	struct got_object *obj = NULL;
326 	char *id_str = NULL;
327 	char *path_got = NULL;
328 
329 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
330 	    GOT_WORKTREE_GOT_DIR) == -1) {
331 		err = got_error_from_errno("asprintf");
332 		path_got = NULL;
333 		goto done;
334 	}
335 
336 	err = got_object_open(&obj, repo, commit_id);
337 	if (err)
338 		return err;
339 
340 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
341 		err = got_error(GOT_ERR_OBJ_TYPE);
342 		goto done;
343 	}
344 
345 	/* Record our base commit. */
346 	err = got_object_id_str(&id_str, commit_id);
347 	if (err)
348 		goto done;
349 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
350 	if (err)
351 		goto done;
352 
353 	free(worktree->base_commit_id);
354 	worktree->base_commit_id = got_object_id_dup(commit_id);
355 	if (worktree->base_commit_id == NULL) {
356 		err = got_error_from_errno("got_object_id_dup");
357 		goto done;
358 	}
359 done:
360 	if (obj)
361 		got_object_close(obj);
362 	free(id_str);
363 	free(path_got);
364 	return err;
365 }
366 
367 const struct got_gotconfig *
368 got_worktree_get_gotconfig(struct got_worktree *worktree)
369 {
370 	return worktree->gotconfig;
371 }
372 
373 static const struct got_error *
374 lock_worktree(struct got_worktree *worktree, int operation)
375 {
376 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
377 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
378 		    : got_error_from_errno2("flock",
379 		    got_worktree_get_root_path(worktree)));
380 	return NULL;
381 }
382 
383 static const struct got_error *
384 add_dir_on_disk(struct got_worktree *worktree, const char *path)
385 {
386 	const struct got_error *err = NULL;
387 	char *abspath;
388 
389 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
390 		return got_error_from_errno("asprintf");
391 
392 	err = got_path_mkdir(abspath);
393 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
394 		struct stat sb;
395 		err = NULL;
396 		if (lstat(abspath, &sb) == -1) {
397 			err = got_error_from_errno2("lstat", abspath);
398 		} else if (!S_ISDIR(sb.st_mode)) {
399 			/* TODO directory is obstructed; do something */
400 			err = got_error_path(abspath, GOT_ERR_FILE_OBSTRUCTED);
401 		}
402 	}
403 	free(abspath);
404 	return err;
405 }
406 
407 static const struct got_error *
408 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
409 {
410 	const struct got_error *err = NULL;
411 	uint8_t fbuf1[8192];
412 	uint8_t fbuf2[8192];
413 	size_t flen1 = 0, flen2 = 0;
414 
415 	*same = 1;
416 
417 	for (;;) {
418 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
419 		if (flen1 == 0 && ferror(f1)) {
420 			err = got_error_from_errno("fread");
421 			break;
422 		}
423 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
424 		if (flen2 == 0 && ferror(f2)) {
425 			err = got_error_from_errno("fread");
426 			break;
427 		}
428 		if (flen1 == 0) {
429 			if (flen2 != 0)
430 				*same = 0;
431 			break;
432 		} else if (flen2 == 0) {
433 			if (flen1 != 0)
434 				*same = 0;
435 			break;
436 		} else if (flen1 == flen2) {
437 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
438 				*same = 0;
439 				break;
440 			}
441 		} else {
442 			*same = 0;
443 			break;
444 		}
445 	}
446 
447 	return err;
448 }
449 
450 static const struct got_error *
451 check_files_equal(int *same, FILE *f1, FILE *f2)
452 {
453 	struct stat sb;
454 	size_t size1, size2;
455 
456 	*same = 1;
457 
458 	if (fstat(fileno(f1), &sb) != 0)
459 		return got_error_from_errno("fstat");
460 	size1 = sb.st_size;
461 
462 	if (fstat(fileno(f2), &sb) != 0)
463 		return got_error_from_errno("fstat");
464 	size2 = sb.st_size;
465 
466 	if (size1 != size2) {
467 		*same = 0;
468 		return NULL;
469 	}
470 
471 	if (fseek(f1, 0L, SEEK_SET) == -1)
472 		return got_ferror(f1, GOT_ERR_IO);
473 	if (fseek(f2, 0L, SEEK_SET) == -1)
474 		return got_ferror(f2, GOT_ERR_IO);
475 
476 	return check_file_contents_equal(same, f1, f2);
477 }
478 
479 static const struct got_error *
480 copy_file_to_fd(off_t *outsize, FILE *f, int outfd)
481 {
482 	uint8_t fbuf[65536];
483 	size_t flen;
484 	ssize_t outlen;
485 
486 	*outsize = 0;
487 
488 	if (fseek(f, 0L, SEEK_SET) == -1)
489 		return got_ferror(f, GOT_ERR_IO);
490 
491 	for (;;) {
492 		flen = fread(fbuf, 1, sizeof(fbuf), f);
493 		if (flen == 0) {
494 			if (ferror(f))
495 				return got_error_from_errno("fread");
496 			if (feof(f))
497 				break;
498 		}
499 		outlen = write(outfd, fbuf, flen);
500 		if (outlen == -1)
501 			return got_error_from_errno("write");
502 		if (outlen != flen)
503 			return got_error(GOT_ERR_IO);
504 		*outsize += outlen;
505 	}
506 
507 	return NULL;
508 }
509 
510 static const struct got_error *
511 merge_binary_file(int *overlapcnt, int merged_fd,
512     FILE *f_deriv, FILE *f_orig, FILE *f_deriv2,
513     const char *label_deriv, const char *label_orig, const char *label_deriv2,
514     const char *ondisk_path)
515 {
516 	const struct got_error *err = NULL;
517 	int same_content, changed_deriv, changed_deriv2;
518 	int fd_orig = -1, fd_deriv = -1, fd_deriv2 = -1;
519 	off_t size_orig = 0, size_deriv = 0, size_deriv2 = 0;
520 	char *path_orig = NULL, *path_deriv = NULL, *path_deriv2 = NULL;
521 	char *base_path_orig = NULL, *base_path_deriv = NULL;
522 	char *base_path_deriv2 = NULL;
523 
524 	*overlapcnt = 0;
525 
526 	err = check_files_equal(&same_content, f_deriv, f_deriv2);
527 	if (err)
528 		return err;
529 
530 	if (same_content)
531 		return copy_file_to_fd(&size_deriv, f_deriv, merged_fd);
532 
533 	err = check_files_equal(&same_content, f_deriv, f_orig);
534 	if (err)
535 		return err;
536 	changed_deriv = !same_content;
537 	err = check_files_equal(&same_content, f_deriv2, f_orig);
538 	if (err)
539 		return err;
540 	changed_deriv2 = !same_content;
541 
542 	if (changed_deriv && changed_deriv2) {
543 		*overlapcnt = 1;
544 		if (asprintf(&base_path_orig, "%s-orig", ondisk_path) == -1) {
545 			err = got_error_from_errno("asprintf");
546 			goto done;
547 		}
548 		if (asprintf(&base_path_deriv, "%s-1", ondisk_path) == -1) {
549 			err = got_error_from_errno("asprintf");
550 			goto done;
551 		}
552 		if (asprintf(&base_path_deriv2, "%s-2", ondisk_path) == -1) {
553 			err = got_error_from_errno("asprintf");
554 			goto done;
555 		}
556 		err = got_opentemp_named_fd(&path_orig, &fd_orig,
557 		    base_path_orig, "");
558 		if (err)
559 			goto done;
560 		err = got_opentemp_named_fd(&path_deriv, &fd_deriv,
561 		    base_path_deriv, "");
562 		if (err)
563 			goto done;
564 		err = got_opentemp_named_fd(&path_deriv2, &fd_deriv2,
565 		    base_path_deriv2, "");
566 		if (err)
567 			goto done;
568 		err = copy_file_to_fd(&size_orig, f_orig, fd_orig);
569 		if (err)
570 			goto done;
571 		err = copy_file_to_fd(&size_deriv, f_deriv, fd_deriv);
572 		if (err)
573 			goto done;
574 		err = copy_file_to_fd(&size_deriv2, f_deriv2, fd_deriv2);
575 		if (err)
576 			goto done;
577 		if (dprintf(merged_fd, "Binary files differ and cannot be "
578 		    "merged automatically:\n") < 0) {
579 			err = got_error_from_errno("dprintf");
580 			goto done;
581 		}
582 		if (dprintf(merged_fd, "%s%s%s\nfile %s\n",
583 		    GOT_DIFF_CONFLICT_MARKER_BEGIN,
584 		    label_deriv ? " " : "",
585 		    label_deriv ? label_deriv : "",
586 		    path_deriv) < 0) {
587 			err = got_error_from_errno("dprintf");
588 			goto done;
589 		}
590 		if (size_orig > 0) {
591 			if (dprintf(merged_fd, "%s%s%s\nfile %s\n",
592 			    GOT_DIFF_CONFLICT_MARKER_ORIG,
593 			    label_orig ? " " : "",
594 			    label_orig ? label_orig : "",
595 			    path_orig) < 0) {
596 				err = got_error_from_errno("dprintf");
597 				goto done;
598 			}
599 		}
600 		if (dprintf(merged_fd, "%s\nfile %s\n%s%s%s\n",
601 		    GOT_DIFF_CONFLICT_MARKER_SEP,
602 		    path_deriv2,
603 		    GOT_DIFF_CONFLICT_MARKER_END,
604 		    label_deriv2 ?  " " : "",
605 		    label_deriv2 ? label_deriv2 : "") < 0) {
606 			err = got_error_from_errno("dprintf");
607 			goto done;
608 		}
609 	} else if (changed_deriv)
610 		err = copy_file_to_fd(&size_deriv, f_deriv, merged_fd);
611 	else if (changed_deriv2)
612 		err = copy_file_to_fd(&size_deriv2, f_deriv2, merged_fd);
613 done:
614 	if (size_orig == 0 && path_orig && unlink(path_orig) == -1 &&
615 	    err == NULL)
616 		err = got_error_from_errno2("unlink", path_orig);
617 	if (fd_orig != -1 && close(fd_orig) == -1 && err == NULL)
618 		err = got_error_from_errno2("close", path_orig);
619 	if (fd_deriv != -1 && close(fd_deriv) == -1 && err == NULL)
620 		err = got_error_from_errno2("close", path_deriv);
621 	if (fd_deriv2 != -1 && close(fd_deriv2) == -1 && err == NULL)
622 		err = got_error_from_errno2("close", path_deriv2);
623 	free(path_orig);
624 	free(path_deriv);
625 	free(path_deriv2);
626 	free(base_path_orig);
627 	free(base_path_deriv);
628 	free(base_path_deriv2);
629 	return err;
630 }
631 
632 /*
633  * Perform a 3-way merge where the file f_orig acts as the common
634  * ancestor, the file f_deriv acts as the first derived version,
635  * and the file f_deriv2 acts as the second derived version.
636  * The merge result will be written to a new file at ondisk_path; any
637  * existing file at this path will be replaced.
638  */
639 static const struct got_error *
640 merge_file(int *local_changes_subsumed, struct got_worktree *worktree,
641     FILE *f_orig, FILE *f_deriv, FILE *f_deriv2, const char *ondisk_path,
642     const char *path, uint16_t st_mode,
643     const char *label_orig, const char *label_deriv, const char *label_deriv2,
644     enum got_diff_algorithm diff_algo, struct got_repository *repo,
645     got_worktree_checkout_cb progress_cb, void *progress_arg)
646 {
647 	const struct got_error *err = NULL;
648 	int merged_fd = -1;
649 	FILE *f_merged = NULL;
650 	char *merged_path = NULL, *base_path = NULL;
651 	int overlapcnt = 0;
652 	char *parent = NULL;
653 
654 	*local_changes_subsumed = 0;
655 
656 	err = got_path_dirname(&parent, ondisk_path);
657 	if (err)
658 		return err;
659 
660 	if (asprintf(&base_path, "%s/got-merged", parent) == -1) {
661 		err = got_error_from_errno("asprintf");
662 		goto done;
663 	}
664 
665 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path, "");
666 	if (err)
667 		goto done;
668 
669 	err = got_merge_diff3(&overlapcnt, merged_fd, f_deriv, f_orig,
670 	    f_deriv2, label_deriv, label_orig, label_deriv2, diff_algo);
671 	if (err) {
672 		if (err->code != GOT_ERR_FILE_BINARY)
673 			goto done;
674 		err = merge_binary_file(&overlapcnt, merged_fd, f_deriv,
675 		    f_orig, f_deriv2, label_deriv, label_orig, label_deriv2,
676 		    ondisk_path);
677 		if (err)
678 			goto done;
679 	}
680 
681 	err = (*progress_cb)(progress_arg,
682 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
683 	if (err)
684 		goto done;
685 
686 	if (fsync(merged_fd) != 0) {
687 		err = got_error_from_errno("fsync");
688 		goto done;
689 	}
690 
691 	f_merged = fdopen(merged_fd, "r");
692 	if (f_merged == NULL) {
693 		err = got_error_from_errno("fdopen");
694 		goto done;
695 	}
696 	merged_fd = -1;
697 
698 	/* Check if a clean merge has subsumed all local changes. */
699 	if (overlapcnt == 0) {
700 		err = check_files_equal(local_changes_subsumed, f_deriv,
701 		    f_merged);
702 		if (err)
703 			goto done;
704 	}
705 
706 	if (fchmod(fileno(f_merged), apply_umask(st_mode)) != 0) {
707 		err = got_error_from_errno2("fchmod", merged_path);
708 		goto done;
709 	}
710 
711 	if (rename(merged_path, ondisk_path) != 0) {
712 		err = got_error_from_errno3("rename", merged_path,
713 		    ondisk_path);
714 		goto done;
715 	}
716 done:
717 	if (err) {
718 		if (merged_path)
719 			unlink(merged_path);
720 	}
721 	if (merged_fd != -1 && close(merged_fd) == -1 && err == NULL)
722 		err = got_error_from_errno("close");
723 	if (f_merged && fclose(f_merged) == EOF && err == NULL)
724 		err = got_error_from_errno("fclose");
725 	free(merged_path);
726 	free(base_path);
727 	free(parent);
728 	return err;
729 }
730 
731 static const struct got_error *
732 update_symlink(const char *ondisk_path, const char *target_path,
733     size_t target_len)
734 {
735 	/* This is not atomic but matches what 'ln -sf' does. */
736 	if (unlink(ondisk_path) == -1)
737 		return got_error_from_errno2("unlink", ondisk_path);
738 	if (symlink(target_path, ondisk_path) == -1)
739 		return got_error_from_errno3("symlink", target_path,
740 		    ondisk_path);
741 	return NULL;
742 }
743 
744 /*
745  * Overwrite a symlink (or a regular file in case there was a "bad" symlink)
746  * in the work tree with a file that contains conflict markers and the
747  * conflicting target paths of the original version, a "derived version"
748  * of a symlink from an incoming change, and a local version of the symlink.
749  *
750  * The original versions's target path can be NULL if it is not available,
751  * such as if both derived versions added a new symlink at the same path.
752  *
753  * The incoming derived symlink target is NULL in case the incoming change
754  * has deleted this symlink.
755  */
756 static const struct got_error *
757 install_symlink_conflict(const char *deriv_target,
758     struct got_object_id *deriv_base_commit_id, const char *orig_target,
759     const char *label_orig, const char *local_target, const char *ondisk_path)
760 {
761 	const struct got_error *err;
762 	char *id_str = NULL, *label_deriv = NULL, *path = NULL;
763 	FILE *f = NULL;
764 
765 	err = got_object_id_str(&id_str, deriv_base_commit_id);
766 	if (err)
767 		return got_error_from_errno("asprintf");
768 
769 	if (asprintf(&label_deriv, "%s: commit %s",
770 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
771 		err = got_error_from_errno("asprintf");
772 		goto done;
773 	}
774 
775 	err = got_opentemp_named(&path, &f, "got-symlink-conflict", "");
776 	if (err)
777 		goto done;
778 
779 	if (fchmod(fileno(f), apply_umask(GOT_DEFAULT_FILE_MODE)) == -1) {
780 		err = got_error_from_errno2("fchmod", path);
781 		goto done;
782 	}
783 
784 	if (fprintf(f, "%s %s\n%s\n%s%s%s%s%s\n%s\n%s\n",
785 	    GOT_DIFF_CONFLICT_MARKER_BEGIN, label_deriv,
786 	    deriv_target ? deriv_target : "(symlink was deleted)",
787 	    orig_target ? label_orig : "",
788 	    orig_target ? "\n" : "",
789 	    orig_target ? orig_target : "",
790 	    orig_target ? "\n" : "",
791 	    GOT_DIFF_CONFLICT_MARKER_SEP,
792 	    local_target, GOT_DIFF_CONFLICT_MARKER_END) < 0) {
793 		err = got_error_from_errno2("fprintf", path);
794 		goto done;
795 	}
796 
797 	if (unlink(ondisk_path) == -1) {
798 		err = got_error_from_errno2("unlink", ondisk_path);
799 		goto done;
800 	}
801 	if (rename(path, ondisk_path) == -1) {
802 		err = got_error_from_errno3("rename", path, ondisk_path);
803 		goto done;
804 	}
805 done:
806 	if (f != NULL && fclose(f) == EOF && err == NULL)
807 		err = got_error_from_errno2("fclose", path);
808 	free(path);
809 	free(id_str);
810 	free(label_deriv);
811 	return err;
812 }
813 
814 /* forward declaration */
815 static const struct got_error *
816 merge_blob(int *, struct got_worktree *, struct got_blob_object *,
817     const char *, const char *, uint16_t, const char *,
818     struct got_blob_object *, struct got_object_id *,
819     struct got_repository *, got_worktree_checkout_cb, void *);
820 
821 /*
822  * Merge a symlink into the work tree, where blob_orig acts as the common
823  * ancestor, deriv_target is the link target of the first derived version,
824  * and the symlink on disk acts as the second derived version.
825  * Assume that contents of both blobs represent symlinks.
826  */
827 static const struct got_error *
828 merge_symlink(struct got_worktree *worktree,
829     struct got_blob_object *blob_orig, const char *ondisk_path,
830     const char *path, const char *label_orig, const char *deriv_target,
831     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
832     got_worktree_checkout_cb progress_cb, void *progress_arg)
833 {
834 	const struct got_error *err = NULL;
835 	char *ancestor_target = NULL;
836 	struct stat sb;
837 	ssize_t ondisk_len, deriv_len;
838 	char ondisk_target[PATH_MAX];
839 	int have_local_change = 0;
840 	int have_incoming_change = 0;
841 
842 	if (lstat(ondisk_path, &sb) == -1)
843 		return got_error_from_errno2("lstat", ondisk_path);
844 
845 	ondisk_len = readlink(ondisk_path, ondisk_target,
846 	    sizeof(ondisk_target));
847 	if (ondisk_len == -1) {
848 		err = got_error_from_errno2("readlink",
849 		    ondisk_path);
850 		goto done;
851 	}
852 	ondisk_target[ondisk_len] = '\0';
853 
854 	if (blob_orig) {
855 		err = got_object_blob_read_to_str(&ancestor_target, blob_orig);
856 		if (err)
857 			goto done;
858 	}
859 
860 	if (ancestor_target == NULL ||
861 	    (ondisk_len != strlen(ancestor_target) ||
862 	    memcmp(ondisk_target, ancestor_target, ondisk_len) != 0))
863 		have_local_change = 1;
864 
865 	deriv_len = strlen(deriv_target);
866 	if (ancestor_target == NULL ||
867 	    (deriv_len != strlen(ancestor_target) ||
868 	    memcmp(deriv_target, ancestor_target, deriv_len) != 0))
869 		have_incoming_change = 1;
870 
871 	if (!have_local_change && !have_incoming_change) {
872 		if (ancestor_target) {
873 			/* Both sides made the same change. */
874 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
875 			    path);
876 		} else if (deriv_len == ondisk_len &&
877 		    memcmp(ondisk_target, deriv_target, deriv_len) == 0) {
878 			/* Both sides added the same symlink. */
879 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
880 			    path);
881 		} else {
882 			/* Both sides added symlinks which don't match. */
883 			err = install_symlink_conflict(deriv_target,
884 			    deriv_base_commit_id, ancestor_target,
885 			    label_orig, ondisk_target, ondisk_path);
886 			if (err)
887 				goto done;
888 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
889 			    path);
890 		}
891 	} else if (!have_local_change && have_incoming_change) {
892 		/* Apply the incoming change. */
893 		err = update_symlink(ondisk_path, deriv_target,
894 		    strlen(deriv_target));
895 		if (err)
896 			goto done;
897 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
898 	} else if (have_local_change && have_incoming_change) {
899 		if (deriv_len == ondisk_len &&
900 		    memcmp(deriv_target, ondisk_target, deriv_len) == 0) {
901 			/* Both sides made the same change. */
902 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
903 			    path);
904 		} else {
905 			err = install_symlink_conflict(deriv_target,
906 			    deriv_base_commit_id, ancestor_target, label_orig,
907 			    ondisk_target, ondisk_path);
908 			if (err)
909 				goto done;
910 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
911 			    path);
912 		}
913 	}
914 
915 done:
916 	free(ancestor_target);
917 	return err;
918 }
919 
920 static const struct got_error *
921 dump_symlink_target_path_to_file(FILE **outfile, const char *ondisk_path)
922 {
923 	const struct got_error *err = NULL;
924 	char target_path[PATH_MAX];
925 	ssize_t target_len;
926 	size_t n;
927 	FILE *f;
928 
929 	*outfile = NULL;
930 
931 	f = got_opentemp();
932 	if (f == NULL)
933 		return got_error_from_errno("got_opentemp");
934 	target_len = readlink(ondisk_path, target_path, sizeof(target_path));
935 	if (target_len == -1) {
936 		err = got_error_from_errno2("readlink", ondisk_path);
937 		goto done;
938 	}
939 	n = fwrite(target_path, 1, target_len, f);
940 	if (n != target_len) {
941 		err = got_ferror(f, GOT_ERR_IO);
942 		goto done;
943 	}
944 	if (fflush(f) == EOF) {
945 		err = got_error_from_errno("fflush");
946 		goto done;
947 	}
948 	if (fseek(f, 0L, SEEK_SET) == -1) {
949 		err = got_ferror(f, GOT_ERR_IO);
950 		goto done;
951 	}
952 done:
953 	if (err)
954 		fclose(f);
955 	else
956 		*outfile = f;
957 	return err;
958 }
959 
960 /*
961  * Perform a 3-way merge where blob_orig acts as the common ancestor,
962  * blob_deriv acts as the first derived version, and the file on disk
963  * acts as the second derived version.
964  */
965 static const struct got_error *
966 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
967     struct got_blob_object *blob_orig, const char *ondisk_path,
968     const char *path, uint16_t st_mode, const char *label_orig,
969     struct got_blob_object *blob_deriv,
970     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
971     got_worktree_checkout_cb progress_cb, void *progress_arg)
972 {
973 	const struct got_error *err = NULL;
974 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
975 	char *blob_orig_path = NULL;
976 	char *blob_deriv_path = NULL, *base_path = NULL, *id_str = NULL;
977 	char *label_deriv = NULL, *parent = NULL;
978 
979 	*local_changes_subsumed = 0;
980 
981 	err = got_path_dirname(&parent, ondisk_path);
982 	if (err)
983 		return err;
984 
985 	if (blob_orig) {
986 		if (asprintf(&base_path, "%s/got-merge-blob-orig",
987 		    parent) == -1) {
988 			err = got_error_from_errno("asprintf");
989 			base_path = NULL;
990 			goto done;
991 		}
992 
993 		err = got_opentemp_named(&blob_orig_path, &f_orig,
994 		    base_path, "");
995 		if (err)
996 			goto done;
997 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
998 		    blob_orig);
999 		if (err)
1000 			goto done;
1001 		free(base_path);
1002 	} else {
1003 		/*
1004 		 * No common ancestor exists. This is an "add vs add" conflict
1005 		 * and we simply use an empty ancestor file to make both files
1006 		 * appear in the merged result in their entirety.
1007 		 */
1008 		f_orig = got_opentemp();
1009 		if (f_orig == NULL) {
1010 			err = got_error_from_errno("got_opentemp");
1011 			goto done;
1012 		}
1013 	}
1014 
1015 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
1016 		err = got_error_from_errno("asprintf");
1017 		base_path = NULL;
1018 		goto done;
1019 	}
1020 
1021 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path, "");
1022 	if (err)
1023 		goto done;
1024 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
1025 	    blob_deriv);
1026 	if (err)
1027 		goto done;
1028 
1029 	err = got_object_id_str(&id_str, deriv_base_commit_id);
1030 	if (err)
1031 		goto done;
1032 	if (asprintf(&label_deriv, "%s: commit %s",
1033 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
1034 		err = got_error_from_errno("asprintf");
1035 		goto done;
1036 	}
1037 
1038 	/*
1039 	 * In order the run a 3-way merge with a symlink we copy the symlink's
1040 	 * target path into a temporary file and use that file with diff3.
1041 	 */
1042 	if (S_ISLNK(st_mode)) {
1043 		err = dump_symlink_target_path_to_file(&f_deriv2, ondisk_path);
1044 		if (err)
1045 			goto done;
1046 	} else {
1047 		int fd;
1048 		fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1049 		if (fd == -1) {
1050 			err = got_error_from_errno2("open", ondisk_path);
1051 			goto done;
1052 		}
1053 		f_deriv2 = fdopen(fd, "r");
1054 		if (f_deriv2 == NULL) {
1055 			err = got_error_from_errno2("fdopen", ondisk_path);
1056 			close(fd);
1057 			goto done;
1058 		}
1059 	}
1060 
1061 	err = merge_file(local_changes_subsumed, worktree, f_orig, f_deriv,
1062 	    f_deriv2, ondisk_path, path, st_mode, label_orig, label_deriv,
1063 	    NULL, GOT_DIFF_ALGORITHM_MYERS, repo, progress_cb, progress_arg);
1064 done:
1065 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
1066 		err = got_error_from_errno("fclose");
1067 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
1068 		err = got_error_from_errno("fclose");
1069 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
1070 		err = got_error_from_errno("fclose");
1071 	free(base_path);
1072 	if (blob_orig_path) {
1073 		unlink(blob_orig_path);
1074 		free(blob_orig_path);
1075 	}
1076 	if (blob_deriv_path) {
1077 		unlink(blob_deriv_path);
1078 		free(blob_deriv_path);
1079 	}
1080 	free(id_str);
1081 	free(label_deriv);
1082 	free(parent);
1083 	return err;
1084 }
1085 
1086 static const struct got_error *
1087 create_fileindex_entry(struct got_fileindex_entry **new_iep,
1088     struct got_fileindex *fileindex, struct got_object_id *base_commit_id,
1089     int wt_fd, const char *path, struct got_object_id *blob_id)
1090 {
1091 	const struct got_error *err = NULL;
1092 	struct got_fileindex_entry *new_ie;
1093 
1094 	*new_iep = NULL;
1095 
1096 	err = got_fileindex_entry_alloc(&new_ie, path);
1097 	if (err)
1098 		return err;
1099 
1100 	err = got_fileindex_entry_update(new_ie, wt_fd, path,
1101 	    blob_id->sha1, base_commit_id->sha1, 1);
1102 	if (err)
1103 		goto done;
1104 
1105 	err = got_fileindex_entry_add(fileindex, new_ie);
1106 done:
1107 	if (err)
1108 		got_fileindex_entry_free(new_ie);
1109 	else
1110 		*new_iep = new_ie;
1111 	return err;
1112 }
1113 
1114 static mode_t
1115 get_ondisk_perms(int executable, mode_t st_mode)
1116 {
1117 	mode_t xbits = S_IXUSR;
1118 
1119 	if (executable) {
1120 		/* Map read bits to execute bits. */
1121 		if (st_mode & S_IRGRP)
1122 			xbits |= S_IXGRP;
1123 		if (st_mode & S_IROTH)
1124 			xbits |= S_IXOTH;
1125 		return st_mode | xbits;
1126 	}
1127 
1128 	return st_mode;
1129 }
1130 
1131 static mode_t
1132 apply_umask(mode_t mode)
1133 {
1134 	mode_t um;
1135 
1136 	um = umask(000);
1137 	umask(um);
1138 	return mode & ~um;
1139 }
1140 
1141 /* forward declaration */
1142 static const struct got_error *
1143 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1144     const char *path, mode_t te_mode, mode_t st_mode,
1145     struct got_blob_object *blob, int restoring_missing_file,
1146     int reverting_versioned_file, int installing_bad_symlink,
1147     int path_is_unversioned, struct got_repository *repo,
1148     got_worktree_checkout_cb progress_cb, void *progress_arg);
1149 
1150 /*
1151  * This function assumes that the provided symlink target points at a
1152  * safe location in the work tree!
1153  */
1154 static const struct got_error *
1155 replace_existing_symlink(int *did_something, const char *ondisk_path,
1156     const char *target_path, size_t target_len)
1157 {
1158 	const struct got_error *err = NULL;
1159 	ssize_t elen;
1160 	char etarget[PATH_MAX];
1161 	int fd;
1162 
1163 	*did_something = 0;
1164 
1165 	/*
1166 	 * "Bad" symlinks (those pointing outside the work tree or into the
1167 	 * .got directory) are installed in the work tree as a regular file
1168 	 * which contains the bad symlink target path.
1169 	 * The new symlink target has already been checked for safety by our
1170 	 * caller. If we can successfully open a regular file then we simply
1171 	 * replace this file with a symlink below.
1172 	 */
1173 	fd = open(ondisk_path, O_RDWR | O_EXCL | O_NOFOLLOW | O_CLOEXEC);
1174 	if (fd == -1) {
1175 		if (!got_err_open_nofollow_on_symlink())
1176 			return got_error_from_errno2("open", ondisk_path);
1177 
1178 		/* We are updating an existing on-disk symlink. */
1179 		elen = readlink(ondisk_path, etarget, sizeof(etarget));
1180 		if (elen == -1)
1181 			return got_error_from_errno2("readlink", ondisk_path);
1182 
1183 		if (elen == target_len &&
1184 		    memcmp(etarget, target_path, target_len) == 0)
1185 			return NULL; /* nothing to do */
1186 	}
1187 
1188 	*did_something = 1;
1189 	err = update_symlink(ondisk_path, target_path, target_len);
1190 	if (fd != -1 && close(fd) == -1 && err == NULL)
1191 		err = got_error_from_errno2("close", ondisk_path);
1192 	return err;
1193 }
1194 
1195 static const struct got_error *
1196 is_bad_symlink_target(int *is_bad_symlink, const char *target_path,
1197     size_t target_len, const char *ondisk_path, const char *wtroot_path)
1198 {
1199 	const struct got_error *err = NULL;
1200 	char canonpath[PATH_MAX];
1201 	char *path_got = NULL;
1202 
1203 	*is_bad_symlink = 0;
1204 
1205 	if (target_len >= sizeof(canonpath)) {
1206 		*is_bad_symlink = 1;
1207 		return NULL;
1208 	}
1209 
1210 	/*
1211 	 * We do not use realpath(3) to resolve the symlink's target
1212 	 * path because we don't want to resolve symlinks recursively.
1213 	 * Instead we make the path absolute and then canonicalize it.
1214 	 * Relative symlink target lookup should begin at the directory
1215 	 * in which the blob object is being installed.
1216 	 */
1217 	if (!got_path_is_absolute(target_path)) {
1218 		char *abspath, *parent;
1219 		err = got_path_dirname(&parent, ondisk_path);
1220 		if (err)
1221 			return err;
1222 		if (asprintf(&abspath, "%s/%s",  parent, target_path) == -1) {
1223 			free(parent);
1224 			return got_error_from_errno("asprintf");
1225 		}
1226 		free(parent);
1227 		if (strlen(abspath) >= sizeof(canonpath)) {
1228 			err = got_error_path(abspath, GOT_ERR_BAD_PATH);
1229 			free(abspath);
1230 			return err;
1231 		}
1232 		err = got_canonpath(abspath, canonpath, sizeof(canonpath));
1233 		free(abspath);
1234 		if (err)
1235 			return err;
1236 	} else {
1237 		err = got_canonpath(target_path, canonpath, sizeof(canonpath));
1238 		if (err)
1239 			return err;
1240 	}
1241 
1242 	/* Only allow symlinks pointing at paths within the work tree. */
1243 	if (!got_path_is_child(canonpath, wtroot_path, strlen(wtroot_path))) {
1244 		*is_bad_symlink = 1;
1245 		return NULL;
1246 	}
1247 
1248 	/* Do not allow symlinks pointing into the .got directory. */
1249 	if (asprintf(&path_got, "%s/%s", wtroot_path,
1250 	    GOT_WORKTREE_GOT_DIR) == -1)
1251 		return got_error_from_errno("asprintf");
1252 	if (got_path_is_child(canonpath, path_got, strlen(path_got)))
1253 		*is_bad_symlink = 1;
1254 
1255 	free(path_got);
1256 	return NULL;
1257 }
1258 
1259 static const struct got_error *
1260 install_symlink(int *is_bad_symlink, struct got_worktree *worktree,
1261     const char *ondisk_path, const char *path, struct got_blob_object *blob,
1262     int restoring_missing_file, int reverting_versioned_file,
1263     int path_is_unversioned, int allow_bad_symlinks,
1264     struct got_repository *repo,
1265     got_worktree_checkout_cb progress_cb, void *progress_arg)
1266 {
1267 	const struct got_error *err = NULL;
1268 	char target_path[PATH_MAX];
1269 	size_t len, target_len = 0;
1270 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1271 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1272 
1273 	*is_bad_symlink = 0;
1274 
1275 	/*
1276 	 * Blob object content specifies the target path of the link.
1277 	 * If a symbolic link cannot be installed we instead create
1278 	 * a regular file which contains the link target path stored
1279 	 * in the blob object.
1280 	 */
1281 	do {
1282 		err = got_object_blob_read_block(&len, blob);
1283 		if (err)
1284 			return err;
1285 
1286 		if (len + target_len >= sizeof(target_path)) {
1287 			/* Path too long; install as a regular file. */
1288 			*is_bad_symlink = 1;
1289 			got_object_blob_rewind(blob);
1290 			return install_blob(worktree, ondisk_path, path,
1291 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1292 			    restoring_missing_file, reverting_versioned_file,
1293 			    1, path_is_unversioned, repo, progress_cb,
1294 			    progress_arg);
1295 		}
1296 		if (len > 0) {
1297 			/* Skip blob object header first time around. */
1298 			memcpy(target_path + target_len, buf + hdrlen,
1299 			    len - hdrlen);
1300 			target_len += len - hdrlen;
1301 			hdrlen = 0;
1302 		}
1303 	} while (len != 0);
1304 	target_path[target_len] = '\0';
1305 
1306 	err = is_bad_symlink_target(is_bad_symlink, target_path, target_len,
1307 	    ondisk_path, worktree->root_path);
1308 	if (err)
1309 		return err;
1310 
1311 	if (*is_bad_symlink && !allow_bad_symlinks) {
1312 		/* install as a regular file */
1313 		got_object_blob_rewind(blob);
1314 		err = install_blob(worktree, ondisk_path, path,
1315 		    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1316 		    restoring_missing_file, reverting_versioned_file, 1,
1317 		    path_is_unversioned, repo, progress_cb, progress_arg);
1318 		return err;
1319 	}
1320 
1321 	if (symlink(target_path, ondisk_path) == -1) {
1322 		if (errno == EEXIST) {
1323 			int symlink_replaced;
1324 			if (path_is_unversioned) {
1325 				err = (*progress_cb)(progress_arg,
1326 				    GOT_STATUS_UNVERSIONED, path);
1327 				return err;
1328 			}
1329 			err = replace_existing_symlink(&symlink_replaced,
1330 			    ondisk_path, target_path, target_len);
1331 			if (err)
1332 				return err;
1333 			if (progress_cb) {
1334 				if (symlink_replaced) {
1335 					err = (*progress_cb)(progress_arg,
1336 					    reverting_versioned_file ?
1337 					    GOT_STATUS_REVERT :
1338 					    GOT_STATUS_UPDATE, path);
1339 				} else {
1340 					err = (*progress_cb)(progress_arg,
1341 					    GOT_STATUS_EXISTS, path);
1342 				}
1343 			}
1344 			return err; /* Nothing else to do. */
1345 		}
1346 
1347 		if (errno == ENOENT) {
1348 			char *parent;
1349 			err = got_path_dirname(&parent, ondisk_path);
1350 			if (err)
1351 				return err;
1352 			err = add_dir_on_disk(worktree, parent);
1353 			free(parent);
1354 			if (err)
1355 				return err;
1356 			/*
1357 			 * Retry, and fall through to error handling
1358 			 * below if this second attempt fails.
1359 			 */
1360 			if (symlink(target_path, ondisk_path) != -1) {
1361 				err = NULL; /* success */
1362 				return err;
1363 			}
1364 		}
1365 
1366 		/* Handle errors from first or second creation attempt. */
1367 		if (errno == ENAMETOOLONG) {
1368 			/* bad target path; install as a regular file */
1369 			*is_bad_symlink = 1;
1370 			got_object_blob_rewind(blob);
1371 			err = install_blob(worktree, ondisk_path, path,
1372 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1373 			    restoring_missing_file, reverting_versioned_file, 1,
1374 			    path_is_unversioned, repo,
1375 			    progress_cb, progress_arg);
1376 		} else if (errno == ENOTDIR) {
1377 			err = got_error_path(ondisk_path,
1378 			    GOT_ERR_FILE_OBSTRUCTED);
1379 		} else {
1380 			err = got_error_from_errno3("symlink",
1381 			    target_path, ondisk_path);
1382 		}
1383 	} else if (progress_cb)
1384 		err = (*progress_cb)(progress_arg, reverting_versioned_file ?
1385 		    GOT_STATUS_REVERT : GOT_STATUS_ADD, path);
1386 	return err;
1387 }
1388 
1389 static const struct got_error *
1390 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1391     const char *path, mode_t te_mode, mode_t st_mode,
1392     struct got_blob_object *blob, int restoring_missing_file,
1393     int reverting_versioned_file, int installing_bad_symlink,
1394     int path_is_unversioned, struct got_repository *repo,
1395     got_worktree_checkout_cb progress_cb, void *progress_arg)
1396 {
1397 	const struct got_error *err = NULL;
1398 	int fd = -1;
1399 	size_t len, hdrlen;
1400 	int update = 0;
1401 	char *tmppath = NULL;
1402 	mode_t mode;
1403 
1404 	mode = get_ondisk_perms(te_mode & S_IXUSR, GOT_DEFAULT_FILE_MODE);
1405 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW |
1406 	    O_CLOEXEC, mode);
1407 	if (fd == -1) {
1408 		if (errno == ENOENT) {
1409 			char *parent;
1410 			err = got_path_dirname(&parent, path);
1411 			if (err)
1412 				return err;
1413 			err = add_dir_on_disk(worktree, parent);
1414 			free(parent);
1415 			if (err)
1416 				return err;
1417 			fd = open(ondisk_path,
1418 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW | O_CLOEXEC,
1419 			    mode);
1420 			if (fd == -1)
1421 				return got_error_from_errno2("open",
1422 				    ondisk_path);
1423 		} else if (errno == EEXIST) {
1424 			if (path_is_unversioned) {
1425 				err = (*progress_cb)(progress_arg,
1426 				    GOT_STATUS_UNVERSIONED, path);
1427 				goto done;
1428 			}
1429 			if (!(S_ISLNK(st_mode) && S_ISREG(te_mode)) &&
1430 			    !S_ISREG(st_mode) && !installing_bad_symlink) {
1431 				/* TODO file is obstructed; do something */
1432 				err = got_error_path(ondisk_path,
1433 				    GOT_ERR_FILE_OBSTRUCTED);
1434 				goto done;
1435 			} else {
1436 				err = got_opentemp_named_fd(&tmppath, &fd,
1437 				    ondisk_path, "");
1438 				if (err)
1439 					goto done;
1440 				update = 1;
1441 
1442 				if (fchmod(fd, apply_umask(mode)) == -1) {
1443 					err = got_error_from_errno2("fchmod",
1444 					    tmppath);
1445 					goto done;
1446 				}
1447 			}
1448 		} else
1449 			return got_error_from_errno2("open", ondisk_path);
1450 	}
1451 
1452 	if (progress_cb) {
1453 		if (restoring_missing_file)
1454 			err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING,
1455 			    path);
1456 		else if (reverting_versioned_file)
1457 			err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT,
1458 			    path);
1459 		else
1460 			err = (*progress_cb)(progress_arg,
1461 			    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
1462 		if (err)
1463 			goto done;
1464 	}
1465 
1466 	hdrlen = got_object_blob_get_hdrlen(blob);
1467 	do {
1468 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
1469 		err = got_object_blob_read_block(&len, blob);
1470 		if (err)
1471 			break;
1472 		if (len > 0) {
1473 			/* Skip blob object header first time around. */
1474 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
1475 			if (outlen == -1) {
1476 				err = got_error_from_errno("write");
1477 				goto done;
1478 			} else if (outlen != len - hdrlen) {
1479 				err = got_error(GOT_ERR_IO);
1480 				goto done;
1481 			}
1482 			hdrlen = 0;
1483 		}
1484 	} while (len != 0);
1485 
1486 	if (fsync(fd) != 0) {
1487 		err = got_error_from_errno("fsync");
1488 		goto done;
1489 	}
1490 
1491 	if (update) {
1492 		if (S_ISLNK(st_mode) && unlink(ondisk_path) == -1) {
1493 			err = got_error_from_errno2("unlink", ondisk_path);
1494 			goto done;
1495 		}
1496 		if (rename(tmppath, ondisk_path) != 0) {
1497 			err = got_error_from_errno3("rename", tmppath,
1498 			    ondisk_path);
1499 			goto done;
1500 		}
1501 		free(tmppath);
1502 		tmppath = NULL;
1503 	}
1504 
1505 done:
1506 	if (fd != -1 && close(fd) == -1 && err == NULL)
1507 		err = got_error_from_errno("close");
1508 	if (tmppath != NULL && unlink(tmppath) == -1 && err == NULL)
1509 		err = got_error_from_errno2("unlink", tmppath);
1510 	free(tmppath);
1511 	return err;
1512 }
1513 
1514 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
1515 static const struct got_error *
1516 get_modified_file_content_status(unsigned char *status, FILE *f)
1517 {
1518 	const struct got_error *err = NULL;
1519 	const char *markers[3] = {
1520 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
1521 		GOT_DIFF_CONFLICT_MARKER_SEP,
1522 		GOT_DIFF_CONFLICT_MARKER_END
1523 	};
1524 	int i = 0;
1525 	char *line = NULL;
1526 	size_t linesize = 0;
1527 	ssize_t linelen;
1528 
1529 	while (*status == GOT_STATUS_MODIFY) {
1530 		linelen = getline(&line, &linesize, f);
1531 		if (linelen == -1) {
1532 			if (feof(f))
1533 				break;
1534 			err = got_ferror(f, GOT_ERR_IO);
1535 			break;
1536 		}
1537 
1538 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1539 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1540 			    == 0)
1541 				*status = GOT_STATUS_CONFLICT;
1542 			else
1543 				i++;
1544 		}
1545 	}
1546 	free(line);
1547 
1548 	return err;
1549 }
1550 
1551 static int
1552 xbit_differs(struct got_fileindex_entry *ie, uint16_t st_mode)
1553 {
1554 	mode_t ie_mode = got_fileindex_perms_to_st(ie);
1555 	return ((ie_mode & S_IXUSR) != (st_mode & S_IXUSR));
1556 }
1557 
1558 static int
1559 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1560 {
1561 	return !(ie->ctime_sec == sb->st_ctim.tv_sec &&
1562 	    ie->ctime_nsec == sb->st_ctim.tv_nsec &&
1563 	    ie->mtime_sec == sb->st_mtim.tv_sec &&
1564 	    ie->mtime_nsec == sb->st_mtim.tv_nsec &&
1565 	    ie->size == (sb->st_size & 0xffffffff) &&
1566 	    !xbit_differs(ie, sb->st_mode));
1567 }
1568 
1569 static unsigned char
1570 get_staged_status(struct got_fileindex_entry *ie)
1571 {
1572 	switch (got_fileindex_entry_stage_get(ie)) {
1573 	case GOT_FILEIDX_STAGE_ADD:
1574 		return GOT_STATUS_ADD;
1575 	case GOT_FILEIDX_STAGE_DELETE:
1576 		return GOT_STATUS_DELETE;
1577 	case GOT_FILEIDX_STAGE_MODIFY:
1578 		return GOT_STATUS_MODIFY;
1579 	default:
1580 		return GOT_STATUS_NO_CHANGE;
1581 	}
1582 }
1583 
1584 static const struct got_error *
1585 get_symlink_modification_status(unsigned char *status,
1586     struct got_fileindex_entry *ie, const char *abspath,
1587     int dirfd, const char *de_name, struct got_blob_object *blob)
1588 {
1589 	const struct got_error *err = NULL;
1590 	char target_path[PATH_MAX];
1591 	char etarget[PATH_MAX];
1592 	ssize_t elen;
1593 	size_t len, target_len = 0;
1594 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1595 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1596 
1597 	*status = GOT_STATUS_NO_CHANGE;
1598 
1599 	/* Blob object content specifies the target path of the link. */
1600 	do {
1601 		err = got_object_blob_read_block(&len, blob);
1602 		if (err)
1603 			return err;
1604 		if (len + target_len >= sizeof(target_path)) {
1605 			/*
1606 			 * Should not happen. The blob contents were OK
1607 			 * when this symlink was installed.
1608 			 */
1609 			return got_error(GOT_ERR_NO_SPACE);
1610 		}
1611 		if (len > 0) {
1612 			/* Skip blob object header first time around. */
1613 			memcpy(target_path + target_len, buf + hdrlen,
1614 			    len - hdrlen);
1615 			target_len += len - hdrlen;
1616 			hdrlen = 0;
1617 		}
1618 	} while (len != 0);
1619 	target_path[target_len] = '\0';
1620 
1621 	if (dirfd != -1) {
1622 		elen = readlinkat(dirfd, de_name, etarget, sizeof(etarget));
1623 		if (elen == -1)
1624 			return got_error_from_errno2("readlinkat", abspath);
1625 	} else {
1626 		elen = readlink(abspath, etarget, sizeof(etarget));
1627 		if (elen == -1)
1628 			return got_error_from_errno2("readlink", abspath);
1629 	}
1630 
1631 	if (elen != target_len || memcmp(etarget, target_path, target_len) != 0)
1632 		*status = GOT_STATUS_MODIFY;
1633 
1634 	return NULL;
1635 }
1636 
1637 static const struct got_error *
1638 get_file_status(unsigned char *status, struct stat *sb,
1639     struct got_fileindex_entry *ie, const char *abspath,
1640     int dirfd, const char *de_name, struct got_repository *repo)
1641 {
1642 	const struct got_error *err = NULL;
1643 	struct got_object_id id;
1644 	size_t hdrlen;
1645 	int fd = -1, fd1 = -1;
1646 	FILE *f = NULL;
1647 	uint8_t fbuf[8192];
1648 	struct got_blob_object *blob = NULL;
1649 	size_t flen, blen;
1650 	unsigned char staged_status = get_staged_status(ie);
1651 
1652 	*status = GOT_STATUS_NO_CHANGE;
1653 	memset(sb, 0, sizeof(*sb));
1654 
1655 	/*
1656 	 * Whenever the caller provides a directory descriptor and a
1657 	 * directory entry name for the file, use them! This prevents
1658 	 * race conditions if filesystem paths change beneath our feet.
1659 	 */
1660 	if (dirfd != -1) {
1661 		if (fstatat(dirfd, de_name, sb, AT_SYMLINK_NOFOLLOW) == -1) {
1662 			if (errno == ENOENT) {
1663 				if (got_fileindex_entry_has_file_on_disk(ie))
1664 					*status = GOT_STATUS_MISSING;
1665 				else
1666 					*status = GOT_STATUS_DELETE;
1667 				goto done;
1668 			}
1669 			err = got_error_from_errno2("fstatat", abspath);
1670 			goto done;
1671 		}
1672 	} else {
1673 		fd = open(abspath, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1674 		if (fd == -1 && errno != ENOENT &&
1675 		    !got_err_open_nofollow_on_symlink())
1676 			return got_error_from_errno2("open", abspath);
1677 		else if (fd == -1 && got_err_open_nofollow_on_symlink()) {
1678 			if (lstat(abspath, sb) == -1)
1679 				return got_error_from_errno2("lstat", abspath);
1680 		} else if (fd == -1 || fstat(fd, sb) == -1) {
1681 			if (errno == ENOENT) {
1682 				if (got_fileindex_entry_has_file_on_disk(ie))
1683 					*status = GOT_STATUS_MISSING;
1684 				else
1685 					*status = GOT_STATUS_DELETE;
1686 				goto done;
1687 			}
1688 			err = got_error_from_errno2("fstat", abspath);
1689 			goto done;
1690 		}
1691 	}
1692 
1693 	if (!S_ISREG(sb->st_mode) && !S_ISLNK(sb->st_mode)) {
1694 		*status = GOT_STATUS_OBSTRUCTED;
1695 		goto done;
1696 	}
1697 
1698 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1699 		*status = GOT_STATUS_DELETE;
1700 		goto done;
1701 	} else if (!got_fileindex_entry_has_blob(ie) &&
1702 	    staged_status != GOT_STATUS_ADD) {
1703 		*status = GOT_STATUS_ADD;
1704 		goto done;
1705 	}
1706 
1707 	if (!stat_info_differs(ie, sb))
1708 		goto done;
1709 
1710 	if (S_ISLNK(sb->st_mode) &&
1711 	    got_fileindex_entry_filetype_get(ie) != GOT_FILEIDX_MODE_SYMLINK) {
1712 		*status = GOT_STATUS_MODIFY;
1713 		goto done;
1714 	}
1715 
1716 	if (staged_status == GOT_STATUS_MODIFY ||
1717 	    staged_status == GOT_STATUS_ADD)
1718 		memcpy(id.sha1, ie->staged_blob_sha1, sizeof(id.sha1));
1719 	else
1720 		memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1721 
1722 	fd1 = got_opentempfd();
1723 	if (fd1 == -1) {
1724 		err = got_error_from_errno("got_opentempfd");
1725 		goto done;
1726 	}
1727 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf), fd1);
1728 	if (err)
1729 		goto done;
1730 
1731 	if (S_ISLNK(sb->st_mode)) {
1732 		err = get_symlink_modification_status(status, ie,
1733 		    abspath, dirfd, de_name, blob);
1734 		goto done;
1735 	}
1736 
1737 	if (dirfd != -1) {
1738 		fd = openat(dirfd, de_name, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
1739 		if (fd == -1) {
1740 			err = got_error_from_errno2("openat", abspath);
1741 			goto done;
1742 		}
1743 	}
1744 
1745 	f = fdopen(fd, "r");
1746 	if (f == NULL) {
1747 		err = got_error_from_errno2("fdopen", abspath);
1748 		goto done;
1749 	}
1750 	fd = -1;
1751 	hdrlen = got_object_blob_get_hdrlen(blob);
1752 	for (;;) {
1753 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1754 		err = got_object_blob_read_block(&blen, blob);
1755 		if (err)
1756 			goto done;
1757 		/* Skip length of blob object header first time around. */
1758 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1759 		if (flen == 0 && ferror(f)) {
1760 			err = got_error_from_errno("fread");
1761 			goto done;
1762 		}
1763 		if (blen - hdrlen == 0) {
1764 			if (flen != 0)
1765 				*status = GOT_STATUS_MODIFY;
1766 			break;
1767 		} else if (flen == 0) {
1768 			if (blen - hdrlen != 0)
1769 				*status = GOT_STATUS_MODIFY;
1770 			break;
1771 		} else if (blen - hdrlen == flen) {
1772 			/* Skip blob object header first time around. */
1773 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1774 				*status = GOT_STATUS_MODIFY;
1775 				break;
1776 			}
1777 		} else {
1778 			*status = GOT_STATUS_MODIFY;
1779 			break;
1780 		}
1781 		hdrlen = 0;
1782 	}
1783 
1784 	if (*status == GOT_STATUS_MODIFY) {
1785 		rewind(f);
1786 		err = get_modified_file_content_status(status, f);
1787 	} else if (xbit_differs(ie, sb->st_mode))
1788 		*status = GOT_STATUS_MODE_CHANGE;
1789 done:
1790 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
1791 		err = got_error_from_errno("close");
1792 	if (blob)
1793 		got_object_blob_close(blob);
1794 	if (f != NULL && fclose(f) == EOF && err == NULL)
1795 		err = got_error_from_errno2("fclose", abspath);
1796 	if (fd != -1 && close(fd) == -1 && err == NULL)
1797 		err = got_error_from_errno2("close", abspath);
1798 	return err;
1799 }
1800 
1801 /*
1802  * Update timestamps in the file index if a file is unmodified and
1803  * we had to run a full content comparison to find out.
1804  */
1805 static const struct got_error *
1806 sync_timestamps(int wt_fd, const char *path, unsigned char status,
1807     struct got_fileindex_entry *ie, struct stat *sb)
1808 {
1809 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1810 		return got_fileindex_entry_update(ie, wt_fd, path,
1811 		    ie->blob_sha1, ie->commit_sha1, 1);
1812 
1813 	return NULL;
1814 }
1815 
1816 static const struct got_error *
1817 update_blob(struct got_worktree *worktree,
1818     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1819     struct got_tree_entry *te, const char *path,
1820     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1821     void *progress_arg)
1822 {
1823 	const struct got_error *err = NULL;
1824 	struct got_blob_object *blob = NULL;
1825 	char *ondisk_path = NULL;
1826 	unsigned char status = GOT_STATUS_NO_CHANGE;
1827 	struct stat sb;
1828 	int fd1 = -1, fd2 = -1;
1829 
1830 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1831 		return got_error_from_errno("asprintf");
1832 
1833 	if (ie) {
1834 		if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE) {
1835 			err = got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1836 			goto done;
1837 		}
1838 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
1839 		    repo);
1840 		if (err)
1841 			goto done;
1842 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1843 			sb.st_mode = got_fileindex_perms_to_st(ie);
1844 	} else {
1845 		if (stat(ondisk_path, &sb) == -1) {
1846 			if (errno != ENOENT) {
1847 				err = got_error_from_errno2("stat",
1848 				    ondisk_path);
1849 				goto done;
1850 			}
1851 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1852 			status = GOT_STATUS_UNVERSIONED;
1853 		} else {
1854 			if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
1855 				status = GOT_STATUS_UNVERSIONED;
1856 			else
1857 				status = GOT_STATUS_OBSTRUCTED;
1858 		}
1859 	}
1860 
1861 	if (status == GOT_STATUS_OBSTRUCTED) {
1862 		if (ie)
1863 			got_fileindex_entry_mark_skipped(ie);
1864 		err = (*progress_cb)(progress_arg, status, path);
1865 		goto done;
1866 	}
1867 	if (status == GOT_STATUS_CONFLICT) {
1868 		if (ie)
1869 			got_fileindex_entry_mark_skipped(ie);
1870 		err = (*progress_cb)(progress_arg, GOT_STATUS_CANNOT_UPDATE,
1871 		    path);
1872 		goto done;
1873 	}
1874 
1875 	if (ie && status != GOT_STATUS_MISSING && S_ISREG(sb.st_mode) &&
1876 	    (S_ISLNK(te->mode) ||
1877 	    (te->mode & S_IXUSR) == (sb.st_mode & S_IXUSR))) {
1878 		/*
1879 		 * This is a regular file or an installed bad symlink.
1880 		 * If the file index indicates that this file is already
1881 		 * up-to-date with respect to the repository we can skip
1882 		 * updating contents of this file.
1883 		 */
1884 		if (got_fileindex_entry_has_commit(ie) &&
1885 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1886 		    SHA1_DIGEST_LENGTH) == 0) {
1887 			/* Same commit. */
1888 			err = sync_timestamps(worktree->root_fd,
1889 			    path, status, ie, &sb);
1890 			if (err)
1891 				goto done;
1892 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1893 			    path);
1894 			goto done;
1895 		}
1896 		if (got_fileindex_entry_has_blob(ie) &&
1897 		    memcmp(ie->blob_sha1, te->id.sha1,
1898 		    SHA1_DIGEST_LENGTH) == 0) {
1899 			/* Different commit but the same blob. */
1900 			err = sync_timestamps(worktree->root_fd,
1901 			    path, status, ie, &sb);
1902 			if (err)
1903 				goto done;
1904 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1905 			    path);
1906 			goto done;
1907 		}
1908 	}
1909 
1910 	fd1 = got_opentempfd();
1911 	if (fd1 == -1) {
1912 		err = got_error_from_errno("got_opentempfd");
1913 		goto done;
1914 	}
1915 	err = got_object_open_as_blob(&blob, repo, &te->id, 8192, fd1);
1916 	if (err)
1917 		goto done;
1918 
1919 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1920 		int update_timestamps;
1921 		struct got_blob_object *blob2 = NULL;
1922 		char *label_orig = NULL;
1923 		if (got_fileindex_entry_has_blob(ie)) {
1924 			fd2 = got_opentempfd();
1925 			if (fd2 == -1) {
1926 				err = got_error_from_errno("got_opentempfd");
1927 				goto done;
1928 			}
1929 			struct got_object_id id2;
1930 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1931 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192,
1932 			    fd2);
1933 			if (err)
1934 				goto done;
1935 		}
1936 		if (got_fileindex_entry_has_commit(ie)) {
1937 			char id_str[SHA1_DIGEST_STRING_LENGTH];
1938 			if (got_sha1_digest_to_str(ie->commit_sha1, id_str,
1939 			    sizeof(id_str)) == NULL) {
1940 				err = got_error_path(id_str,
1941 				    GOT_ERR_BAD_OBJ_ID_STR);
1942 				goto done;
1943 			}
1944 			if (asprintf(&label_orig, "%s: commit %s",
1945 			    GOT_MERGE_LABEL_BASE, id_str) == -1) {
1946 				err = got_error_from_errno("asprintf");
1947 				goto done;
1948 			}
1949 		}
1950 		if (S_ISLNK(te->mode) && S_ISLNK(sb.st_mode)) {
1951 			char *link_target;
1952 			err = got_object_blob_read_to_str(&link_target, blob);
1953 			if (err)
1954 				goto done;
1955 			err = merge_symlink(worktree, blob2, ondisk_path, path,
1956 			    label_orig, link_target, worktree->base_commit_id,
1957 			    repo, progress_cb, progress_arg);
1958 			free(link_target);
1959 		} else {
1960 			err = merge_blob(&update_timestamps, worktree, blob2,
1961 			    ondisk_path, path, sb.st_mode, label_orig, blob,
1962 			    worktree->base_commit_id, repo,
1963 			    progress_cb, progress_arg);
1964 		}
1965 		free(label_orig);
1966 		if (fd2 != -1 && close(fd2) == -1 && err == NULL) {
1967 			err = got_error_from_errno("close");
1968 			goto done;
1969 		}
1970 		if (blob2)
1971 			got_object_blob_close(blob2);
1972 		if (err)
1973 			goto done;
1974 		/*
1975 		 * Do not update timestamps of files with local changes.
1976 		 * Otherwise, a future status walk would treat them as
1977 		 * unmodified files again.
1978 		 */
1979 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
1980 		    blob->id.sha1, worktree->base_commit_id->sha1,
1981 		    update_timestamps);
1982 	} else if (status == GOT_STATUS_MODE_CHANGE) {
1983 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
1984 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
1985 	} else if (status == GOT_STATUS_DELETE) {
1986 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1987 		if (err)
1988 			goto done;
1989 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
1990 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
1991 		if (err)
1992 			goto done;
1993 	} else {
1994 		int is_bad_symlink = 0;
1995 		if (S_ISLNK(te->mode)) {
1996 			err = install_symlink(&is_bad_symlink, worktree,
1997 			    ondisk_path, path, blob,
1998 			    status == GOT_STATUS_MISSING, 0,
1999 			    status == GOT_STATUS_UNVERSIONED, 0,
2000 			    repo, progress_cb, progress_arg);
2001 		} else {
2002 			err = install_blob(worktree, ondisk_path, path,
2003 			    te->mode, sb.st_mode, blob,
2004 			    status == GOT_STATUS_MISSING, 0, 0,
2005 			    status == GOT_STATUS_UNVERSIONED, repo,
2006 			    progress_cb, progress_arg);
2007 		}
2008 		if (err)
2009 			goto done;
2010 
2011 		if (ie) {
2012 			err = got_fileindex_entry_update(ie,
2013 			    worktree->root_fd, path, blob->id.sha1,
2014 			    worktree->base_commit_id->sha1, 1);
2015 		} else {
2016 			err = create_fileindex_entry(&ie, fileindex,
2017 			    worktree->base_commit_id, worktree->root_fd, path,
2018 			    &blob->id);
2019 		}
2020 		if (err)
2021 			goto done;
2022 
2023 		if (is_bad_symlink) {
2024 			got_fileindex_entry_filetype_set(ie,
2025 			    GOT_FILEIDX_MODE_BAD_SYMLINK);
2026 		}
2027 	}
2028 
2029 	if (fd1 != -1 && close(fd1) == -1 && err == NULL) {
2030 		err = got_error_from_errno("close");
2031 		goto done;
2032 	}
2033 	got_object_blob_close(blob);
2034 done:
2035 	free(ondisk_path);
2036 	return err;
2037 }
2038 
2039 static const struct got_error *
2040 remove_ondisk_file(const char *root_path, const char *path)
2041 {
2042 	const struct got_error *err = NULL;
2043 	char *ondisk_path = NULL, *parent = NULL;
2044 
2045 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
2046 		return got_error_from_errno("asprintf");
2047 
2048 	if (unlink(ondisk_path) == -1) {
2049 		if (errno != ENOENT)
2050 			err = got_error_from_errno2("unlink", ondisk_path);
2051 	} else {
2052 		size_t root_len = strlen(root_path);
2053 		err = got_path_dirname(&parent, ondisk_path);
2054 		if (err)
2055 			goto done;
2056 		while (got_path_cmp(parent, root_path,
2057 		    strlen(parent), root_len) != 0) {
2058 			free(ondisk_path);
2059 			ondisk_path = parent;
2060 			parent = NULL;
2061 			if (rmdir(ondisk_path) == -1) {
2062 				if (errno != ENOTEMPTY)
2063 					err = got_error_from_errno2("rmdir",
2064 					    ondisk_path);
2065 				break;
2066 			}
2067 			err = got_path_dirname(&parent, ondisk_path);
2068 			if (err)
2069 				break;
2070 		}
2071 	}
2072 done:
2073 	free(ondisk_path);
2074 	free(parent);
2075 	return err;
2076 }
2077 
2078 static const struct got_error *
2079 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
2080     struct got_fileindex_entry *ie, struct got_repository *repo,
2081     got_worktree_checkout_cb progress_cb, void *progress_arg)
2082 {
2083 	const struct got_error *err = NULL;
2084 	unsigned char status;
2085 	struct stat sb;
2086 	char *ondisk_path;
2087 
2088 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
2089 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
2090 
2091 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
2092 	    == -1)
2093 		return got_error_from_errno("asprintf");
2094 
2095 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, repo);
2096 	if (err)
2097 		goto done;
2098 
2099 	if (S_ISLNK(sb.st_mode) && status != GOT_STATUS_NO_CHANGE) {
2100 		char ondisk_target[PATH_MAX];
2101 		ssize_t ondisk_len = readlink(ondisk_path, ondisk_target,
2102 		    sizeof(ondisk_target));
2103 		if (ondisk_len == -1) {
2104 			err = got_error_from_errno2("readlink", ondisk_path);
2105 			goto done;
2106 		}
2107 		ondisk_target[ondisk_len] = '\0';
2108 		err = install_symlink_conflict(NULL, worktree->base_commit_id,
2109 		    NULL, NULL, /* XXX pass common ancestor info? */
2110 		    ondisk_target, ondisk_path);
2111 		if (err)
2112 			goto done;
2113 		err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
2114 		    ie->path);
2115 		goto done;
2116 	}
2117 
2118 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
2119 	    status == GOT_STATUS_ADD) {
2120 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
2121 		if (err)
2122 			goto done;
2123 		/*
2124 		 * Preserve the working file and change the deleted blob's
2125 		 * entry into a schedule-add entry.
2126 		 */
2127 		err = got_fileindex_entry_update(ie, worktree->root_fd,
2128 		    ie->path, NULL, NULL, 0);
2129 	} else {
2130 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
2131 		if (err)
2132 			goto done;
2133 		if (status == GOT_STATUS_NO_CHANGE) {
2134 			err = remove_ondisk_file(worktree->root_path, ie->path);
2135 			if (err)
2136 				goto done;
2137 		}
2138 		got_fileindex_entry_remove(fileindex, ie);
2139 	}
2140 done:
2141 	free(ondisk_path);
2142 	return err;
2143 }
2144 
2145 struct diff_cb_arg {
2146     struct got_fileindex *fileindex;
2147     struct got_worktree *worktree;
2148     struct got_repository *repo;
2149     got_worktree_checkout_cb progress_cb;
2150     void *progress_arg;
2151     got_cancel_cb cancel_cb;
2152     void *cancel_arg;
2153 };
2154 
2155 static const struct got_error *
2156 diff_old_new(void *arg, struct got_fileindex_entry *ie,
2157     struct got_tree_entry *te, const char *parent_path)
2158 {
2159 	struct diff_cb_arg *a = arg;
2160 
2161 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2162 		return got_error(GOT_ERR_CANCELLED);
2163 
2164 	return update_blob(a->worktree, a->fileindex, ie, te,
2165 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
2166 }
2167 
2168 static const struct got_error *
2169 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2170 {
2171 	struct diff_cb_arg *a = arg;
2172 
2173 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2174 		return got_error(GOT_ERR_CANCELLED);
2175 
2176 	return delete_blob(a->worktree, a->fileindex, ie,
2177 	    a->repo, a->progress_cb, a->progress_arg);
2178 }
2179 
2180 static const struct got_error *
2181 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
2182 {
2183 	struct diff_cb_arg *a = arg;
2184 	const struct got_error *err;
2185 	char *path;
2186 
2187 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2188 		return got_error(GOT_ERR_CANCELLED);
2189 
2190 	if (got_object_tree_entry_is_submodule(te))
2191 		return NULL;
2192 
2193 	if (asprintf(&path, "%s%s%s", parent_path,
2194 	    parent_path[0] ? "/" : "", te->name)
2195 	    == -1)
2196 		return got_error_from_errno("asprintf");
2197 
2198 	if (S_ISDIR(te->mode))
2199 		err = add_dir_on_disk(a->worktree, path);
2200 	else
2201 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
2202 		    a->repo, a->progress_cb, a->progress_arg);
2203 
2204 	free(path);
2205 	return err;
2206 }
2207 
2208 const struct got_error *
2209 got_worktree_get_uuid(char **uuidstr, struct got_worktree *worktree)
2210 {
2211 	uint32_t uuid_status;
2212 
2213 	uuid_to_string(&worktree->uuid, uuidstr, &uuid_status);
2214 	if (uuid_status != uuid_s_ok) {
2215 		*uuidstr = NULL;
2216 		return got_error_uuid(uuid_status, "uuid_to_string");
2217 	}
2218 
2219 	return NULL;
2220 }
2221 
2222 static const struct got_error *
2223 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
2224 {
2225 	const struct got_error *err = NULL;
2226 	char *uuidstr = NULL;
2227 
2228 	*refname = NULL;
2229 
2230 	err = got_worktree_get_uuid(&uuidstr, worktree);
2231 	if (err)
2232 		return err;
2233 
2234 	if (asprintf(refname, "%s-%s", prefix, uuidstr) == -1) {
2235 		err = got_error_from_errno("asprintf");
2236 		*refname = NULL;
2237 	}
2238 	free(uuidstr);
2239 	return err;
2240 }
2241 
2242 const struct got_error *
2243 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
2244 {
2245 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
2246 }
2247 
2248 static const struct got_error *
2249 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
2250 {
2251 	return get_ref_name(refname, worktree,
2252 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
2253 }
2254 
2255 static const struct got_error *
2256 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
2257 {
2258 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
2259 }
2260 
2261 static const struct got_error *
2262 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
2263 {
2264 	return get_ref_name(refname, worktree,
2265 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
2266 }
2267 
2268 static const struct got_error *
2269 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
2270 {
2271 	return get_ref_name(refname, worktree,
2272 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
2273 }
2274 
2275 static const struct got_error *
2276 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
2277 {
2278 	return get_ref_name(refname, worktree,
2279 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
2280 }
2281 
2282 static const struct got_error *
2283 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
2284 {
2285 	return get_ref_name(refname, worktree,
2286 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
2287 }
2288 
2289 static const struct got_error *
2290 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
2291 {
2292 	return get_ref_name(refname, worktree,
2293 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
2294 }
2295 
2296 static const struct got_error *
2297 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
2298 {
2299 	return get_ref_name(refname, worktree,
2300 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
2301 }
2302 
2303 const struct got_error *
2304 got_worktree_get_histedit_script_path(char **path,
2305     struct got_worktree *worktree)
2306 {
2307 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
2308 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
2309 		*path = NULL;
2310 		return got_error_from_errno("asprintf");
2311 	}
2312 	return NULL;
2313 }
2314 
2315 static const struct got_error *
2316 get_merge_branch_ref_name(char **refname, struct got_worktree *worktree)
2317 {
2318 	return get_ref_name(refname, worktree,
2319 	    GOT_WORKTREE_MERGE_BRANCH_REF_PREFIX);
2320 }
2321 
2322 static const struct got_error *
2323 get_merge_commit_ref_name(char **refname, struct got_worktree *worktree)
2324 {
2325 	return get_ref_name(refname, worktree,
2326 	    GOT_WORKTREE_MERGE_COMMIT_REF_PREFIX);
2327 }
2328 
2329 /*
2330  * Prevent Git's garbage collector from deleting our base commit by
2331  * setting a reference to our base commit's ID.
2332  */
2333 static const struct got_error *
2334 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
2335 {
2336 	const struct got_error *err = NULL;
2337 	struct got_reference *ref = NULL;
2338 	char *refname;
2339 
2340 	err = got_worktree_get_base_ref_name(&refname, worktree);
2341 	if (err)
2342 		return err;
2343 
2344 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
2345 	if (err)
2346 		goto done;
2347 
2348 	err = got_ref_write(ref, repo);
2349 done:
2350 	free(refname);
2351 	if (ref)
2352 		got_ref_close(ref);
2353 	return err;
2354 }
2355 
2356 static const struct got_error *
2357 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
2358 {
2359 	const struct got_error *err = NULL;
2360 
2361 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
2362 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2363 		err = got_error_from_errno("asprintf");
2364 		*fileindex_path = NULL;
2365 	}
2366 	return err;
2367 }
2368 
2369 
2370 static const struct got_error *
2371 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
2372     struct got_worktree *worktree)
2373 {
2374 	const struct got_error *err = NULL;
2375 	FILE *index = NULL;
2376 
2377 	*fileindex_path = NULL;
2378 	*fileindex = got_fileindex_alloc();
2379 	if (*fileindex == NULL)
2380 		return got_error_from_errno("got_fileindex_alloc");
2381 
2382 	err = get_fileindex_path(fileindex_path, worktree);
2383 	if (err)
2384 		goto done;
2385 
2386 	index = fopen(*fileindex_path, "rbe");
2387 	if (index == NULL) {
2388 		if (errno != ENOENT)
2389 			err = got_error_from_errno2("fopen", *fileindex_path);
2390 	} else {
2391 		err = got_fileindex_read(*fileindex, index);
2392 		if (fclose(index) == EOF && err == NULL)
2393 			err = got_error_from_errno("fclose");
2394 	}
2395 done:
2396 	if (err) {
2397 		free(*fileindex_path);
2398 		*fileindex_path = NULL;
2399 		got_fileindex_free(*fileindex);
2400 		*fileindex = NULL;
2401 	}
2402 	return err;
2403 }
2404 
2405 struct bump_base_commit_id_arg {
2406 	struct got_object_id *base_commit_id;
2407 	const char *path;
2408 	size_t path_len;
2409 	const char *entry_name;
2410 	got_worktree_checkout_cb progress_cb;
2411 	void *progress_arg;
2412 };
2413 
2414 /* Bump base commit ID of all files within an updated part of the work tree. */
2415 static const struct got_error *
2416 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
2417 {
2418 	const struct got_error *err;
2419 	struct bump_base_commit_id_arg *a = arg;
2420 
2421 	if (a->entry_name) {
2422 		if (strcmp(ie->path, a->path) != 0)
2423 			return NULL;
2424 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
2425 		return NULL;
2426 
2427 	if (got_fileindex_entry_was_skipped(ie))
2428 		return NULL;
2429 
2430 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
2431 	    SHA1_DIGEST_LENGTH) == 0)
2432 		return NULL;
2433 
2434 	if (a->progress_cb) {
2435 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
2436 		    ie->path);
2437 		if (err)
2438 			return err;
2439 	}
2440 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
2441 	return NULL;
2442 }
2443 
2444 static const struct got_error *
2445 bump_base_commit_id_everywhere(struct got_worktree *worktree,
2446     struct got_fileindex *fileindex,
2447     got_worktree_checkout_cb progress_cb, void *progress_arg)
2448 {
2449 	struct bump_base_commit_id_arg bbc_arg;
2450 
2451 	bbc_arg.base_commit_id = worktree->base_commit_id;
2452 	bbc_arg.entry_name = NULL;
2453 	bbc_arg.path = "";
2454 	bbc_arg.path_len = 0;
2455 	bbc_arg.progress_cb = progress_cb;
2456 	bbc_arg.progress_arg = progress_arg;
2457 
2458 	return got_fileindex_for_each_entry_safe(fileindex,
2459 	    bump_base_commit_id, &bbc_arg);
2460 }
2461 
2462 static const struct got_error *
2463 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
2464 {
2465 	const struct got_error *err = NULL;
2466 	char *new_fileindex_path = NULL;
2467 	FILE *new_index = NULL;
2468 	struct timespec timeout;
2469 
2470 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2471 	    fileindex_path, "");
2472 	if (err)
2473 		goto done;
2474 
2475 	err = got_fileindex_write(fileindex, new_index);
2476 	if (err)
2477 		goto done;
2478 
2479 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2480 		err = got_error_from_errno3("rename", new_fileindex_path,
2481 		    fileindex_path);
2482 		unlink(new_fileindex_path);
2483 	}
2484 
2485 	/*
2486 	 * Sleep for a short amount of time to ensure that files modified after
2487 	 * this program exits have a different time stamp from the one which
2488 	 * was recorded in the file index.
2489 	 */
2490 	timeout.tv_sec = 0;
2491 	timeout.tv_nsec = 1;
2492 	nanosleep(&timeout,  NULL);
2493 done:
2494 	if (new_index)
2495 		fclose(new_index);
2496 	free(new_fileindex_path);
2497 	return err;
2498 }
2499 
2500 static const struct got_error *
2501 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
2502     struct got_object_id **tree_id, const char *wt_relpath,
2503     struct got_commit_object *base_commit, struct got_worktree *worktree,
2504     struct got_repository *repo)
2505 {
2506 	const struct got_error *err = NULL;
2507 	struct got_object_id *id = NULL;
2508 	char *in_repo_path = NULL;
2509 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
2510 
2511 	*entry_type = GOT_OBJ_TYPE_ANY;
2512 	*tree_relpath = NULL;
2513 	*tree_id = NULL;
2514 
2515 	if (wt_relpath[0] == '\0') {
2516 		/* Check out all files within the work tree. */
2517 		*entry_type = GOT_OBJ_TYPE_TREE;
2518 		*tree_relpath = strdup("");
2519 		if (*tree_relpath == NULL) {
2520 			err = got_error_from_errno("strdup");
2521 			goto done;
2522 		}
2523 		err = got_object_id_by_path(tree_id, repo, base_commit,
2524 		    worktree->path_prefix);
2525 		if (err)
2526 			goto done;
2527 		return NULL;
2528 	}
2529 
2530 	/* Check out a subset of files in the work tree. */
2531 
2532 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
2533 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
2534 		err = got_error_from_errno("asprintf");
2535 		goto done;
2536 	}
2537 
2538 	err = got_object_id_by_path(&id, repo, base_commit, in_repo_path);
2539 	if (err)
2540 		goto done;
2541 
2542 	free(in_repo_path);
2543 	in_repo_path = NULL;
2544 
2545 	err = got_object_get_type(entry_type, repo, id);
2546 	if (err)
2547 		goto done;
2548 
2549 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
2550 		/* Check out a single file. */
2551 		if (strchr(wt_relpath, '/')  == NULL) {
2552 			/* Check out a single file in work tree's root dir. */
2553 			in_repo_path = strdup(worktree->path_prefix);
2554 			if (in_repo_path == NULL) {
2555 				err = got_error_from_errno("strdup");
2556 				goto done;
2557 			}
2558 			*tree_relpath = strdup("");
2559 			if (*tree_relpath == NULL) {
2560 				err = got_error_from_errno("strdup");
2561 				goto done;
2562 			}
2563 		} else {
2564 			/* Check out a single file in a subdirectory. */
2565 			err = got_path_dirname(tree_relpath, wt_relpath);
2566 			if (err)
2567 				return err;
2568 			if (asprintf(&in_repo_path, "%s%s%s",
2569 			    worktree->path_prefix, is_root_wt ? "" : "/",
2570 			    *tree_relpath) == -1) {
2571 				err = got_error_from_errno("asprintf");
2572 				goto done;
2573 			}
2574 		}
2575 		err = got_object_id_by_path(tree_id, repo,
2576 		    base_commit, in_repo_path);
2577 	} else {
2578 		/* Check out all files within a subdirectory. */
2579 		*tree_id = got_object_id_dup(id);
2580 		if (*tree_id == NULL) {
2581 			err = got_error_from_errno("got_object_id_dup");
2582 			goto done;
2583 		}
2584 		*tree_relpath = strdup(wt_relpath);
2585 		if (*tree_relpath == NULL) {
2586 			err = got_error_from_errno("strdup");
2587 			goto done;
2588 		}
2589 	}
2590 done:
2591 	free(id);
2592 	free(in_repo_path);
2593 	if (err) {
2594 		*entry_type = GOT_OBJ_TYPE_ANY;
2595 		free(*tree_relpath);
2596 		*tree_relpath = NULL;
2597 		free(*tree_id);
2598 		*tree_id = NULL;
2599 	}
2600 	return err;
2601 }
2602 
2603 static const struct got_error *
2604 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2605     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
2606     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2607     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
2608 {
2609 	const struct got_error *err = NULL;
2610 	struct got_commit_object *commit = NULL;
2611 	struct got_tree_object *tree = NULL;
2612 	struct got_fileindex_diff_tree_cb diff_cb;
2613 	struct diff_cb_arg arg;
2614 
2615 	err = ref_base_commit(worktree, repo);
2616 	if (err) {
2617 		if (!(err->code == GOT_ERR_ERRNO &&
2618 		    (errno == EACCES || errno == EROFS)))
2619 			goto done;
2620 		err = (*progress_cb)(progress_arg,
2621 		    GOT_STATUS_BASE_REF_ERR, worktree->root_path);
2622 		if (err)
2623 			return err;
2624 	}
2625 
2626 	err = got_object_open_as_commit(&commit, repo,
2627 	    worktree->base_commit_id);
2628 	if (err)
2629 		goto done;
2630 
2631 	err = got_object_open_as_tree(&tree, repo, tree_id);
2632 	if (err)
2633 		goto done;
2634 
2635 	if (entry_name &&
2636 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
2637 		err = got_error_path(entry_name, GOT_ERR_NO_TREE_ENTRY);
2638 		goto done;
2639 	}
2640 
2641 	diff_cb.diff_old_new = diff_old_new;
2642 	diff_cb.diff_old = diff_old;
2643 	diff_cb.diff_new = diff_new;
2644 	arg.fileindex = fileindex;
2645 	arg.worktree = worktree;
2646 	arg.repo = repo;
2647 	arg.progress_cb = progress_cb;
2648 	arg.progress_arg = progress_arg;
2649 	arg.cancel_cb = cancel_cb;
2650 	arg.cancel_arg = cancel_arg;
2651 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
2652 	    entry_name, repo, &diff_cb, &arg);
2653 done:
2654 	if (tree)
2655 		got_object_tree_close(tree);
2656 	if (commit)
2657 		got_object_commit_close(commit);
2658 	return err;
2659 }
2660 
2661 const struct got_error *
2662 got_worktree_checkout_files(struct got_worktree *worktree,
2663     struct got_pathlist_head *paths, struct got_repository *repo,
2664     got_worktree_checkout_cb progress_cb, void *progress_arg,
2665     got_cancel_cb cancel_cb, void *cancel_arg)
2666 {
2667 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2668 	struct got_commit_object *commit = NULL;
2669 	struct got_tree_object *tree = NULL;
2670 	struct got_fileindex *fileindex = NULL;
2671 	char *fileindex_path = NULL;
2672 	struct got_pathlist_entry *pe;
2673 	struct tree_path_data {
2674 		STAILQ_ENTRY(tree_path_data) entry;
2675 		struct got_object_id *tree_id;
2676 		int entry_type;
2677 		char *relpath;
2678 		char *entry_name;
2679 	} *tpd = NULL;
2680 	STAILQ_HEAD(tree_paths, tree_path_data) tree_paths;
2681 
2682 	STAILQ_INIT(&tree_paths);
2683 
2684 	err = lock_worktree(worktree, LOCK_EX);
2685 	if (err)
2686 		return err;
2687 
2688 	err = got_object_open_as_commit(&commit, repo,
2689 	    worktree->base_commit_id);
2690 	if (err)
2691 		goto done;
2692 
2693 	/* Map all specified paths to in-repository trees. */
2694 	TAILQ_FOREACH(pe, paths, entry) {
2695 		tpd = malloc(sizeof(*tpd));
2696 		if (tpd == NULL) {
2697 			err = got_error_from_errno("malloc");
2698 			goto done;
2699 		}
2700 
2701 		err = find_tree_entry_for_checkout(&tpd->entry_type,
2702 		    &tpd->relpath, &tpd->tree_id, pe->path, commit,
2703 		    worktree, repo);
2704 		if (err) {
2705 			free(tpd);
2706 			goto done;
2707 		}
2708 
2709 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
2710 			err = got_path_basename(&tpd->entry_name, pe->path);
2711 			if (err) {
2712 				free(tpd->relpath);
2713 				free(tpd->tree_id);
2714 				free(tpd);
2715 				goto done;
2716 			}
2717 		} else
2718 			tpd->entry_name = NULL;
2719 
2720 		STAILQ_INSERT_TAIL(&tree_paths, tpd, entry);
2721 	}
2722 
2723 	/*
2724 	 * Read the file index.
2725 	 * Checking out files is supposed to be an idempotent operation.
2726 	 * If the on-disk file index is incomplete we will try to complete it.
2727 	 */
2728 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2729 	if (err)
2730 		goto done;
2731 
2732 	tpd = STAILQ_FIRST(&tree_paths);
2733 	TAILQ_FOREACH(pe, paths, entry) {
2734 		struct bump_base_commit_id_arg bbc_arg;
2735 
2736 		err = checkout_files(worktree, fileindex, tpd->relpath,
2737 		    tpd->tree_id, tpd->entry_name, repo,
2738 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
2739 		if (err)
2740 			break;
2741 
2742 		bbc_arg.base_commit_id = worktree->base_commit_id;
2743 		bbc_arg.entry_name = tpd->entry_name;
2744 		bbc_arg.path = pe->path;
2745 		bbc_arg.path_len = pe->path_len;
2746 		bbc_arg.progress_cb = progress_cb;
2747 		bbc_arg.progress_arg = progress_arg;
2748 		err = got_fileindex_for_each_entry_safe(fileindex,
2749 		    bump_base_commit_id, &bbc_arg);
2750 		if (err)
2751 			break;
2752 
2753 		tpd = STAILQ_NEXT(tpd, entry);
2754 	}
2755 	sync_err = sync_fileindex(fileindex, fileindex_path);
2756 	if (sync_err && err == NULL)
2757 		err = sync_err;
2758 done:
2759 	free(fileindex_path);
2760 	if (tree)
2761 		got_object_tree_close(tree);
2762 	if (commit)
2763 		got_object_commit_close(commit);
2764 	if (fileindex)
2765 		got_fileindex_free(fileindex);
2766 	while (!STAILQ_EMPTY(&tree_paths)) {
2767 		tpd = STAILQ_FIRST(&tree_paths);
2768 		STAILQ_REMOVE_HEAD(&tree_paths, entry);
2769 		free(tpd->relpath);
2770 		free(tpd->tree_id);
2771 		free(tpd);
2772 	}
2773 	unlockerr = lock_worktree(worktree, LOCK_SH);
2774 	if (unlockerr && err == NULL)
2775 		err = unlockerr;
2776 	return err;
2777 }
2778 
2779 struct merge_file_cb_arg {
2780     struct got_worktree *worktree;
2781     struct got_fileindex *fileindex;
2782     got_worktree_checkout_cb progress_cb;
2783     void *progress_arg;
2784     got_cancel_cb cancel_cb;
2785     void *cancel_arg;
2786     const char *label_orig;
2787     struct got_object_id *commit_id2;
2788     int allow_bad_symlinks;
2789 };
2790 
2791 static const struct got_error *
2792 merge_file_cb(void *arg, struct got_blob_object *blob1,
2793     struct got_blob_object *blob2, FILE *f1, FILE *f2,
2794     struct got_object_id *id1, struct got_object_id *id2,
2795     const char *path1, const char *path2,
2796     mode_t mode1, mode_t mode2, struct got_repository *repo)
2797 {
2798 	static const struct got_error *err = NULL;
2799 	struct merge_file_cb_arg *a = arg;
2800 	struct got_fileindex_entry *ie;
2801 	char *ondisk_path = NULL;
2802 	struct stat sb;
2803 	unsigned char status;
2804 	int local_changes_subsumed;
2805 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
2806 	char *id_str = NULL, *label_deriv2 = NULL;
2807 
2808 	if (blob1 && blob2) {
2809 		ie = got_fileindex_entry_get(a->fileindex, path2,
2810 		    strlen(path2));
2811 		if (ie == NULL)
2812 			return (*a->progress_cb)(a->progress_arg,
2813 			    GOT_STATUS_MISSING, path2);
2814 
2815 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2816 		    path2) == -1)
2817 			return got_error_from_errno("asprintf");
2818 
2819 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2820 		    repo);
2821 		if (err)
2822 			goto done;
2823 
2824 		if (status == GOT_STATUS_DELETE) {
2825 			err = (*a->progress_cb)(a->progress_arg,
2826 			    GOT_STATUS_MERGE, path2);
2827 			goto done;
2828 		}
2829 		if (status != GOT_STATUS_NO_CHANGE &&
2830 		    status != GOT_STATUS_MODIFY &&
2831 		    status != GOT_STATUS_CONFLICT &&
2832 		    status != GOT_STATUS_ADD) {
2833 			err = (*a->progress_cb)(a->progress_arg, status, path2);
2834 			goto done;
2835 		}
2836 
2837 		if (S_ISLNK(mode1) && S_ISLNK(mode2)) {
2838 			char *link_target2;
2839 			err = got_object_blob_read_to_str(&link_target2, blob2);
2840 			if (err)
2841 				goto done;
2842 			err = merge_symlink(a->worktree, blob1, ondisk_path,
2843 			    path2, a->label_orig, link_target2, a->commit_id2,
2844 			    repo, a->progress_cb, a->progress_arg);
2845 			free(link_target2);
2846 		} else {
2847 			int fd;
2848 
2849 			f_orig = got_opentemp();
2850 			if (f_orig == NULL) {
2851 				err = got_error_from_errno("got_opentemp");
2852 				goto done;
2853 			}
2854 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2855 			    f_orig, blob1);
2856 			if (err)
2857 				goto done;
2858 
2859 			f_deriv2 = got_opentemp();
2860 			if (f_deriv2 == NULL)
2861 				goto done;
2862 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2863 			    f_deriv2, blob2);
2864 			if (err)
2865 				goto done;
2866 
2867 			fd = open(ondisk_path,
2868 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
2869 			if (fd == -1) {
2870 				err = got_error_from_errno2("open",
2871 				    ondisk_path);
2872 				goto done;
2873 			}
2874 			f_deriv = fdopen(fd, "r");
2875 			if (f_deriv == NULL) {
2876 				err = got_error_from_errno2("fdopen",
2877 				    ondisk_path);
2878 				close(fd);
2879 				goto done;
2880 			}
2881 			err = got_object_id_str(&id_str, a->commit_id2);
2882 			if (err)
2883 				goto done;
2884 			if (asprintf(&label_deriv2, "%s: commit %s",
2885 			    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
2886 				err = got_error_from_errno("asprintf");
2887 				goto done;
2888 			}
2889 			err = merge_file(&local_changes_subsumed, a->worktree,
2890 			    f_orig, f_deriv, f_deriv2, ondisk_path, path2,
2891 			    sb.st_mode, a->label_orig, NULL, label_deriv2,
2892 			    GOT_DIFF_ALGORITHM_PATIENCE, repo,
2893 			    a->progress_cb, a->progress_arg);
2894 		}
2895 	} else if (blob1) {
2896 		ie = got_fileindex_entry_get(a->fileindex, path1,
2897 		    strlen(path1));
2898 		if (ie == NULL)
2899 			return (*a->progress_cb)(a->progress_arg,
2900 			    GOT_STATUS_MISSING, path1);
2901 
2902 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2903 		    path1) == -1)
2904 			return got_error_from_errno("asprintf");
2905 
2906 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2907 		    repo);
2908 		if (err)
2909 			goto done;
2910 
2911 		switch (status) {
2912 		case GOT_STATUS_NO_CHANGE:
2913 			err = (*a->progress_cb)(a->progress_arg,
2914 			    GOT_STATUS_DELETE, path1);
2915 			if (err)
2916 				goto done;
2917 			err = remove_ondisk_file(a->worktree->root_path, path1);
2918 			if (err)
2919 				goto done;
2920 			if (ie)
2921 				got_fileindex_entry_mark_deleted_from_disk(ie);
2922 			break;
2923 		case GOT_STATUS_DELETE:
2924 		case GOT_STATUS_MISSING:
2925 			err = (*a->progress_cb)(a->progress_arg,
2926 			    GOT_STATUS_DELETE, path1);
2927 			if (err)
2928 				goto done;
2929 			if (ie)
2930 				got_fileindex_entry_mark_deleted_from_disk(ie);
2931 			break;
2932 		case GOT_STATUS_ADD: {
2933 			struct got_object_id *id;
2934 			FILE *blob1_f;
2935 			off_t blob1_size;
2936 			/*
2937 			 * Delete the added file only if its content already
2938 			 * exists in the repository.
2939 			 */
2940 			err = got_object_blob_file_create(&id, &blob1_f,
2941 			    &blob1_size, path1);
2942 			if (err)
2943 				goto done;
2944 			if (got_object_id_cmp(id, id1) == 0) {
2945 				err = (*a->progress_cb)(a->progress_arg,
2946 				    GOT_STATUS_DELETE, path1);
2947 				if (err)
2948 					goto done;
2949 				err = remove_ondisk_file(a->worktree->root_path,
2950 				    path1);
2951 				if (err)
2952 					goto done;
2953 				if (ie)
2954 					got_fileindex_entry_remove(a->fileindex,
2955 					    ie);
2956 			} else {
2957 				err = (*a->progress_cb)(a->progress_arg,
2958 				    GOT_STATUS_CANNOT_DELETE, path1);
2959 			}
2960 			if (fclose(blob1_f) == EOF && err == NULL)
2961 				err = got_error_from_errno("fclose");
2962 			free(id);
2963 			if (err)
2964 				goto done;
2965 			break;
2966 		}
2967 		case GOT_STATUS_MODIFY:
2968 		case GOT_STATUS_CONFLICT:
2969 			err = (*a->progress_cb)(a->progress_arg,
2970 			    GOT_STATUS_CANNOT_DELETE, path1);
2971 			if (err)
2972 				goto done;
2973 			break;
2974 		case GOT_STATUS_OBSTRUCTED:
2975 			err = (*a->progress_cb)(a->progress_arg, status, path1);
2976 			if (err)
2977 				goto done;
2978 			break;
2979 		default:
2980 			break;
2981 		}
2982 	} else if (blob2) {
2983 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2984 		    path2) == -1)
2985 			return got_error_from_errno("asprintf");
2986 		ie = got_fileindex_entry_get(a->fileindex, path2,
2987 		    strlen(path2));
2988 		if (ie) {
2989 			err = get_file_status(&status, &sb, ie, ondisk_path,
2990 			    -1, NULL, repo);
2991 			if (err)
2992 				goto done;
2993 			if (status != GOT_STATUS_NO_CHANGE &&
2994 			    status != GOT_STATUS_MODIFY &&
2995 			    status != GOT_STATUS_CONFLICT &&
2996 			    status != GOT_STATUS_ADD) {
2997 				err = (*a->progress_cb)(a->progress_arg,
2998 				    status, path2);
2999 				goto done;
3000 			}
3001 			if (S_ISLNK(mode2) && S_ISLNK(sb.st_mode)) {
3002 				char *link_target2;
3003 				err = got_object_blob_read_to_str(&link_target2,
3004 				    blob2);
3005 				if (err)
3006 					goto done;
3007 				err = merge_symlink(a->worktree, NULL,
3008 				    ondisk_path, path2, a->label_orig,
3009 				    link_target2, a->commit_id2, repo,
3010 				    a->progress_cb, a->progress_arg);
3011 				free(link_target2);
3012 			} else if (S_ISREG(sb.st_mode)) {
3013 				err = merge_blob(&local_changes_subsumed,
3014 				    a->worktree, NULL, ondisk_path, path2,
3015 				    sb.st_mode, a->label_orig, blob2,
3016 				    a->commit_id2, repo, a->progress_cb,
3017 				    a->progress_arg);
3018 			} else {
3019 				err = got_error_path(ondisk_path,
3020 				    GOT_ERR_FILE_OBSTRUCTED);
3021 			}
3022 			if (err)
3023 				goto done;
3024 			if (status == GOT_STATUS_DELETE) {
3025 				err = got_fileindex_entry_update(ie,
3026 				    a->worktree->root_fd, path2, blob2->id.sha1,
3027 				    a->worktree->base_commit_id->sha1, 0);
3028 				if (err)
3029 					goto done;
3030 			}
3031 		} else {
3032 			int is_bad_symlink = 0;
3033 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
3034 			if (S_ISLNK(mode2)) {
3035 				err = install_symlink(&is_bad_symlink,
3036 				    a->worktree, ondisk_path, path2, blob2, 0,
3037 				    0, 1, a->allow_bad_symlinks, repo,
3038 				    a->progress_cb, a->progress_arg);
3039 			} else {
3040 				err = install_blob(a->worktree, ondisk_path, path2,
3041 				    mode2, sb.st_mode, blob2, 0, 0, 0, 1, repo,
3042 				    a->progress_cb, a->progress_arg);
3043 			}
3044 			if (err)
3045 				goto done;
3046 			err = got_fileindex_entry_alloc(&ie, path2);
3047 			if (err)
3048 				goto done;
3049 			err = got_fileindex_entry_update(ie,
3050 			    a->worktree->root_fd, path2, NULL, NULL, 1);
3051 			if (err) {
3052 				got_fileindex_entry_free(ie);
3053 				goto done;
3054 			}
3055 			err = got_fileindex_entry_add(a->fileindex, ie);
3056 			if (err) {
3057 				got_fileindex_entry_free(ie);
3058 				goto done;
3059 			}
3060 			if (is_bad_symlink) {
3061 				got_fileindex_entry_filetype_set(ie,
3062 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
3063 			}
3064 		}
3065 	}
3066 done:
3067 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
3068 		err = got_error_from_errno("fclose");
3069 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
3070 		err = got_error_from_errno("fclose");
3071 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
3072 		err = got_error_from_errno("fclose");
3073 	free(id_str);
3074 	free(label_deriv2);
3075 	free(ondisk_path);
3076 	return err;
3077 }
3078 
3079 static const struct got_error *
3080 check_mixed_commits(void *arg, struct got_fileindex_entry *ie)
3081 {
3082 	struct got_worktree *worktree = arg;
3083 
3084 	/* Reject merges into a work tree with mixed base commits. */
3085 	if (got_fileindex_entry_has_commit(ie) &&
3086 	    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
3087 	    SHA1_DIGEST_LENGTH) != 0)
3088 		return got_error(GOT_ERR_MIXED_COMMITS);
3089 
3090 	return NULL;
3091 }
3092 
3093 struct check_merge_conflicts_arg {
3094 	struct got_worktree *worktree;
3095 	struct got_fileindex *fileindex;
3096 	struct got_repository *repo;
3097 };
3098 
3099 static const struct got_error *
3100 check_merge_conflicts(void *arg, struct got_blob_object *blob1,
3101     struct got_blob_object *blob2, FILE *f1, FILE *f2,
3102     struct got_object_id *id1, struct got_object_id *id2,
3103     const char *path1, const char *path2,
3104     mode_t mode1, mode_t mode2, struct got_repository *repo)
3105 {
3106 	const struct got_error *err = NULL;
3107 	struct check_merge_conflicts_arg *a = arg;
3108 	unsigned char status;
3109 	struct stat sb;
3110 	struct got_fileindex_entry *ie;
3111 	const char *path = path2 ? path2 : path1;
3112 	struct got_object_id *id = id2 ? id2 : id1;
3113 	char *ondisk_path;
3114 
3115 	if (id == NULL)
3116 		return NULL;
3117 
3118 	ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
3119 	if (ie == NULL)
3120 		return NULL;
3121 
3122 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3123 	    == -1)
3124 		return got_error_from_errno("asprintf");
3125 
3126 	/* Reject merges into a work tree with conflicted files. */
3127 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
3128 	free(ondisk_path);
3129 	if (err)
3130 		return err;
3131 	if (status == GOT_STATUS_CONFLICT)
3132 		return got_error(GOT_ERR_CONFLICTS);
3133 
3134 	return NULL;
3135 }
3136 
3137 static const struct got_error *
3138 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
3139     const char *fileindex_path, struct got_object_id *commit_id1,
3140     struct got_object_id *commit_id2, struct got_repository *repo,
3141     got_worktree_checkout_cb progress_cb, void *progress_arg,
3142     got_cancel_cb cancel_cb, void *cancel_arg)
3143 {
3144 	const struct got_error *err = NULL, *sync_err;
3145 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
3146 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
3147 	struct got_commit_object *commit1 = NULL, *commit2 = NULL;
3148 	struct check_merge_conflicts_arg cmc_arg;
3149 	struct merge_file_cb_arg arg;
3150 	char *label_orig = NULL;
3151 	FILE *f1 = NULL, *f2 = NULL;
3152 	int fd1 = -1, fd2 = -1;
3153 
3154 	if (commit_id1) {
3155 		err = got_object_open_as_commit(&commit1, repo, commit_id1);
3156 		if (err)
3157 			goto done;
3158 		err = got_object_id_by_path(&tree_id1, repo, commit1,
3159 		    worktree->path_prefix);
3160 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3161 			goto done;
3162 	}
3163 	if (tree_id1) {
3164 		char *id_str;
3165 
3166 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
3167 		if (err)
3168 			goto done;
3169 
3170 		err = got_object_id_str(&id_str, commit_id1);
3171 		if (err)
3172 			goto done;
3173 
3174 		if (asprintf(&label_orig, "%s: commit %s",
3175 		    GOT_MERGE_LABEL_BASE, id_str) == -1) {
3176 			err = got_error_from_errno("asprintf");
3177 			free(id_str);
3178 			goto done;
3179 		}
3180 		free(id_str);
3181 
3182 		f1 = got_opentemp();
3183 		if (f1 == NULL) {
3184 			err = got_error_from_errno("got_opentemp");
3185 			goto done;
3186 		}
3187 	}
3188 
3189 	err = got_object_open_as_commit(&commit2, repo, commit_id2);
3190 	if (err)
3191 		goto done;
3192 
3193 	err = got_object_id_by_path(&tree_id2, repo, commit2,
3194 	    worktree->path_prefix);
3195 	if (err)
3196 		goto done;
3197 
3198 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
3199 	if (err)
3200 		goto done;
3201 
3202 	f2 = got_opentemp();
3203 	if (f2 == NULL) {
3204 		err = got_error_from_errno("got_opentemp");
3205 		goto done;
3206 	}
3207 
3208 	fd1 = got_opentempfd();
3209 	if (fd1 == -1) {
3210 		err = got_error_from_errno("got_opentempfd");
3211 		goto done;
3212 	}
3213 
3214 	fd2 = got_opentempfd();
3215 	if (fd2 == -1) {
3216 		err = got_error_from_errno("got_opentempfd");
3217 		goto done;
3218 	}
3219 
3220 	cmc_arg.worktree = worktree;
3221 	cmc_arg.fileindex = fileindex;
3222 	cmc_arg.repo = repo;
3223 	err = got_diff_tree(tree1, tree2, f1, f2, fd1, fd2, "", "", repo,
3224 	    check_merge_conflicts, &cmc_arg, 0);
3225 	if (err)
3226 		goto done;
3227 
3228 	arg.worktree = worktree;
3229 	arg.fileindex = fileindex;
3230 	arg.progress_cb = progress_cb;
3231 	arg.progress_arg = progress_arg;
3232 	arg.cancel_cb = cancel_cb;
3233 	arg.cancel_arg = cancel_arg;
3234 	arg.label_orig = label_orig;
3235 	arg.commit_id2 = commit_id2;
3236 	arg.allow_bad_symlinks = 1; /* preserve bad symlinks across merges */
3237 	err = got_diff_tree(tree1, tree2, f1, f2, fd1, fd2, "", "", repo,
3238 	    merge_file_cb, &arg, 1);
3239 	sync_err = sync_fileindex(fileindex, fileindex_path);
3240 	if (sync_err && err == NULL)
3241 		err = sync_err;
3242 done:
3243 	if (commit1)
3244 		got_object_commit_close(commit1);
3245 	if (commit2)
3246 		got_object_commit_close(commit2);
3247 	if (tree1)
3248 		got_object_tree_close(tree1);
3249 	if (tree2)
3250 		got_object_tree_close(tree2);
3251 	if (f1 && fclose(f1) == EOF && err == NULL)
3252 		err = got_error_from_errno("fclose");
3253 	if (f2 && fclose(f2) == EOF && err == NULL)
3254 		err = got_error_from_errno("fclose");
3255 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
3256 		err = got_error_from_errno("close");
3257 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
3258 		err = got_error_from_errno("close");
3259 	free(label_orig);
3260 	return err;
3261 }
3262 
3263 const struct got_error *
3264 got_worktree_merge_files(struct got_worktree *worktree,
3265     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
3266     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
3267     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
3268 {
3269 	const struct got_error *err, *unlockerr;
3270 	char *fileindex_path = NULL;
3271 	struct got_fileindex *fileindex = NULL;
3272 
3273 	err = lock_worktree(worktree, LOCK_EX);
3274 	if (err)
3275 		return err;
3276 
3277 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3278 	if (err)
3279 		goto done;
3280 
3281 	err = got_fileindex_for_each_entry_safe(fileindex, check_mixed_commits,
3282 	    worktree);
3283 	if (err)
3284 		goto done;
3285 
3286 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
3287 	    commit_id2, repo, progress_cb, progress_arg,
3288 	    cancel_cb, cancel_arg);
3289 done:
3290 	if (fileindex)
3291 		got_fileindex_free(fileindex);
3292 	free(fileindex_path);
3293 	unlockerr = lock_worktree(worktree, LOCK_SH);
3294 	if (unlockerr && err == NULL)
3295 		err = unlockerr;
3296 	return err;
3297 }
3298 
3299 struct diff_dir_cb_arg {
3300     struct got_fileindex *fileindex;
3301     struct got_worktree *worktree;
3302     const char *status_path;
3303     size_t status_path_len;
3304     struct got_repository *repo;
3305     got_worktree_status_cb status_cb;
3306     void *status_arg;
3307     got_cancel_cb cancel_cb;
3308     void *cancel_arg;
3309     /* A pathlist containing per-directory pathlists of ignore patterns. */
3310     struct got_pathlist_head *ignores;
3311     int report_unchanged;
3312     int no_ignores;
3313 };
3314 
3315 static const struct got_error *
3316 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
3317     int dirfd, const char *de_name,
3318     got_worktree_status_cb status_cb, void *status_arg,
3319     struct got_repository *repo, int report_unchanged)
3320 {
3321 	const struct got_error *err = NULL;
3322 	unsigned char status = GOT_STATUS_NO_CHANGE;
3323 	unsigned char staged_status = get_staged_status(ie);
3324 	struct stat sb;
3325 	struct got_object_id blob_id, commit_id, staged_blob_id;
3326 	struct got_object_id *blob_idp = NULL, *commit_idp = NULL;
3327 	struct got_object_id *staged_blob_idp = NULL;
3328 
3329 	err = get_file_status(&status, &sb, ie, abspath, dirfd, de_name, repo);
3330 	if (err)
3331 		return err;
3332 
3333 	if (status == GOT_STATUS_NO_CHANGE &&
3334 	    staged_status == GOT_STATUS_NO_CHANGE && !report_unchanged)
3335 		return NULL;
3336 
3337 	if (got_fileindex_entry_has_blob(ie)) {
3338 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
3339 		blob_idp = &blob_id;
3340 	}
3341 	if (got_fileindex_entry_has_commit(ie)) {
3342 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
3343 		commit_idp = &commit_id;
3344 	}
3345 	if (staged_status == GOT_STATUS_ADD ||
3346 	    staged_status == GOT_STATUS_MODIFY) {
3347 		memcpy(staged_blob_id.sha1, ie->staged_blob_sha1,
3348 		    SHA1_DIGEST_LENGTH);
3349 		staged_blob_idp = &staged_blob_id;
3350 	}
3351 
3352 	return (*status_cb)(status_arg, status, staged_status,
3353 	    ie->path, blob_idp, staged_blob_idp, commit_idp, dirfd, de_name);
3354 }
3355 
3356 static const struct got_error *
3357 status_old_new(void *arg, struct got_fileindex_entry *ie,
3358     struct dirent *de, const char *parent_path, int dirfd)
3359 {
3360 	const struct got_error *err = NULL;
3361 	struct diff_dir_cb_arg *a = arg;
3362 	char *abspath;
3363 
3364 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3365 		return got_error(GOT_ERR_CANCELLED);
3366 
3367 	if (got_path_cmp(parent_path, a->status_path,
3368 	    strlen(parent_path), a->status_path_len) != 0 &&
3369 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
3370 		return NULL;
3371 
3372 	if (parent_path[0]) {
3373 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
3374 		    parent_path, de->d_name) == -1)
3375 			return got_error_from_errno("asprintf");
3376 	} else {
3377 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
3378 		    de->d_name) == -1)
3379 			return got_error_from_errno("asprintf");
3380 	}
3381 
3382 	err = report_file_status(ie, abspath, dirfd, de->d_name,
3383 	    a->status_cb, a->status_arg, a->repo, a->report_unchanged);
3384 	free(abspath);
3385 	return err;
3386 }
3387 
3388 static const struct got_error *
3389 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
3390 {
3391 	struct diff_dir_cb_arg *a = arg;
3392 	struct got_object_id blob_id, commit_id;
3393 	unsigned char status;
3394 
3395 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3396 		return got_error(GOT_ERR_CANCELLED);
3397 
3398 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
3399 		return NULL;
3400 
3401 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
3402 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
3403 	if (got_fileindex_entry_has_file_on_disk(ie))
3404 		status = GOT_STATUS_MISSING;
3405 	else
3406 		status = GOT_STATUS_DELETE;
3407 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
3408 	    ie->path, &blob_id, NULL, &commit_id, -1, NULL);
3409 }
3410 
3411 static void
3412 free_ignores(struct got_pathlist_head *ignores)
3413 {
3414 	struct got_pathlist_entry *pe;
3415 
3416 	TAILQ_FOREACH(pe, ignores, entry) {
3417 		struct got_pathlist_head *ignorelist = pe->data;
3418 
3419 		got_pathlist_free(ignorelist, GOT_PATHLIST_FREE_PATH);
3420 	}
3421 	got_pathlist_free(ignores, GOT_PATHLIST_FREE_PATH);
3422 }
3423 
3424 static const struct got_error *
3425 read_ignores(struct got_pathlist_head *ignores, const char *path, FILE *f)
3426 {
3427 	const struct got_error *err = NULL;
3428 	struct got_pathlist_entry *pe = NULL;
3429 	struct got_pathlist_head *ignorelist;
3430 	char *line = NULL, *pattern, *dirpath = NULL;
3431 	size_t linesize = 0;
3432 	ssize_t linelen;
3433 
3434 	ignorelist = calloc(1, sizeof(*ignorelist));
3435 	if (ignorelist == NULL)
3436 		return got_error_from_errno("calloc");
3437 	TAILQ_INIT(ignorelist);
3438 
3439 	while ((linelen = getline(&line, &linesize, f)) != -1) {
3440 		if (linelen > 0 && line[linelen - 1] == '\n')
3441 			line[linelen - 1] = '\0';
3442 
3443 		/* Git's ignores may contain comments. */
3444 		if (line[0] == '#')
3445 			continue;
3446 
3447 		/* Git's negated patterns are not (yet?) supported. */
3448 		if (line[0] == '!')
3449 			continue;
3450 
3451 		if (asprintf(&pattern, "%s%s%s", path, path[0] ? "/" : "",
3452 		    line) == -1) {
3453 			err = got_error_from_errno("asprintf");
3454 			goto done;
3455 		}
3456 		err = got_pathlist_insert(NULL, ignorelist, pattern, NULL);
3457 		if (err)
3458 			goto done;
3459 	}
3460 	if (ferror(f)) {
3461 		err = got_error_from_errno("getline");
3462 		goto done;
3463 	}
3464 
3465 	dirpath = strdup(path);
3466 	if (dirpath == NULL) {
3467 		err = got_error_from_errno("strdup");
3468 		goto done;
3469 	}
3470 	err = got_pathlist_insert(&pe, ignores, dirpath, ignorelist);
3471 done:
3472 	free(line);
3473 	if (err || pe == NULL) {
3474 		free(dirpath);
3475 		got_pathlist_free(ignorelist, GOT_PATHLIST_FREE_PATH);
3476 	}
3477 	return err;
3478 }
3479 
3480 static int
3481 match_ignores(struct got_pathlist_head *ignores, const char *path)
3482 {
3483 	struct got_pathlist_entry *pe;
3484 
3485 	/* Handle patterns which match in all directories. */
3486 	TAILQ_FOREACH(pe, ignores, entry) {
3487 		struct got_pathlist_head *ignorelist = pe->data;
3488 		struct got_pathlist_entry *pi;
3489 
3490 		TAILQ_FOREACH(pi, ignorelist, entry) {
3491 			const char *p, *pattern = pi->path;
3492 
3493 			if (strncmp(pattern, "**/", 3) != 0)
3494 				continue;
3495 			pattern += 3;
3496 			p = path;
3497 			while (*p) {
3498 				if (fnmatch(pattern, p,
3499 				    FNM_PATHNAME | FNM_LEADING_DIR)) {
3500 					/* Retry in next directory. */
3501 					while (*p && *p != '/')
3502 						p++;
3503 					while (*p == '/')
3504 						p++;
3505 					continue;
3506 				}
3507 				return 1;
3508 			}
3509 		}
3510 	}
3511 
3512 	/*
3513 	 * The ignores pathlist contains ignore lists from children before
3514 	 * parents, so we can find the most specific ignorelist by walking
3515 	 * ignores backwards.
3516 	 */
3517 	pe = TAILQ_LAST(ignores, got_pathlist_head);
3518 	while (pe) {
3519 		if (got_path_is_child(path, pe->path, pe->path_len)) {
3520 			struct got_pathlist_head *ignorelist = pe->data;
3521 			struct got_pathlist_entry *pi;
3522 			TAILQ_FOREACH(pi, ignorelist, entry) {
3523 				const char *pattern = pi->path;
3524 				int flags = FNM_LEADING_DIR;
3525 				if (strstr(pattern, "/**/") == NULL)
3526 					flags |= FNM_PATHNAME;
3527 				if (fnmatch(pattern, path, flags))
3528 					continue;
3529 				return 1;
3530 			}
3531 		}
3532 		pe = TAILQ_PREV(pe, got_pathlist_head, entry);
3533 	}
3534 
3535 	return 0;
3536 }
3537 
3538 static const struct got_error *
3539 add_ignores(struct got_pathlist_head *ignores, const char *root_path,
3540     const char *path, int dirfd, const char *ignores_filename)
3541 {
3542 	const struct got_error *err = NULL;
3543 	char *ignorespath;
3544 	int fd = -1;
3545 	FILE *ignoresfile = NULL;
3546 
3547 	if (asprintf(&ignorespath, "%s/%s%s%s", root_path, path,
3548 	    path[0] ? "/" : "", ignores_filename) == -1)
3549 		return got_error_from_errno("asprintf");
3550 
3551 	if (dirfd != -1) {
3552 		fd = openat(dirfd, ignores_filename,
3553 		    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
3554 		if (fd == -1) {
3555 			if (errno != ENOENT && errno != EACCES)
3556 				err = got_error_from_errno2("openat",
3557 				    ignorespath);
3558 		} else {
3559 			ignoresfile = fdopen(fd, "r");
3560 			if (ignoresfile == NULL)
3561 				err = got_error_from_errno2("fdopen",
3562 				    ignorespath);
3563 			else {
3564 				fd = -1;
3565 				err = read_ignores(ignores, path, ignoresfile);
3566 			}
3567 		}
3568 	} else {
3569 		ignoresfile = fopen(ignorespath, "re");
3570 		if (ignoresfile == NULL) {
3571 			if (errno != ENOENT && errno != EACCES)
3572 				err = got_error_from_errno2("fopen",
3573 				    ignorespath);
3574 		} else
3575 			err = read_ignores(ignores, path, ignoresfile);
3576 	}
3577 
3578 	if (ignoresfile && fclose(ignoresfile) == EOF && err == NULL)
3579 		err = got_error_from_errno2("fclose", path);
3580 	if (fd != -1 && close(fd) == -1 && err == NULL)
3581 		err = got_error_from_errno2("close", path);
3582 	free(ignorespath);
3583 	return err;
3584 }
3585 
3586 static const struct got_error *
3587 status_new(int *ignore, void *arg, struct dirent *de, const char *parent_path,
3588     int dirfd)
3589 {
3590 	const struct got_error *err = NULL;
3591 	struct diff_dir_cb_arg *a = arg;
3592 	char *path = NULL;
3593 
3594 	if (ignore != NULL)
3595 		*ignore = 0;
3596 
3597 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3598 		return got_error(GOT_ERR_CANCELLED);
3599 
3600 	if (parent_path[0]) {
3601 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
3602 			return got_error_from_errno("asprintf");
3603 	} else {
3604 		path = de->d_name;
3605 	}
3606 
3607 	if (de->d_type == DT_DIR) {
3608 		if (!a->no_ignores && ignore != NULL &&
3609 		    match_ignores(a->ignores, path))
3610 			*ignore = 1;
3611 	} else if (!match_ignores(a->ignores, path) &&
3612 	    got_path_is_child(path, a->status_path, a->status_path_len))
3613 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
3614 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3615 	if (parent_path[0])
3616 		free(path);
3617 	return err;
3618 }
3619 
3620 static const struct got_error *
3621 status_traverse(void *arg, const char *path, int dirfd)
3622 {
3623 	const struct got_error *err = NULL;
3624 	struct diff_dir_cb_arg *a = arg;
3625 
3626 	if (a->no_ignores)
3627 		return NULL;
3628 
3629 	err = add_ignores(a->ignores, a->worktree->root_path,
3630 	    path, dirfd, ".cvsignore");
3631 	if (err)
3632 		return err;
3633 
3634 	err = add_ignores(a->ignores, a->worktree->root_path, path,
3635 	    dirfd, ".gitignore");
3636 
3637 	return err;
3638 }
3639 
3640 static const struct got_error *
3641 report_single_file_status(const char *path, const char *ondisk_path,
3642     struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
3643     void *status_arg, struct got_repository *repo, int report_unchanged,
3644     struct got_pathlist_head *ignores, int no_ignores)
3645 {
3646 	struct got_fileindex_entry *ie;
3647 	struct stat sb;
3648 
3649 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3650 	if (ie)
3651 		return report_file_status(ie, ondisk_path, -1, NULL,
3652 		    status_cb, status_arg, repo, report_unchanged);
3653 
3654 	if (lstat(ondisk_path, &sb) == -1) {
3655 		if (errno != ENOENT)
3656 			return got_error_from_errno2("lstat", ondisk_path);
3657 		return (*status_cb)(status_arg, GOT_STATUS_NONEXISTENT,
3658 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3659 	}
3660 
3661 	if (!no_ignores && match_ignores(ignores, path))
3662 		return NULL;
3663 
3664 	if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
3665 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
3666 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3667 
3668 	return NULL;
3669 }
3670 
3671 static const struct got_error *
3672 add_ignores_from_parent_paths(struct got_pathlist_head *ignores,
3673     const char *root_path, const char *path)
3674 {
3675 	const struct got_error *err;
3676 	char *parent_path, *next_parent_path = NULL;
3677 
3678 	err = add_ignores(ignores, root_path, "", -1,
3679 	    ".cvsignore");
3680 	if (err)
3681 		return err;
3682 
3683 	err = add_ignores(ignores, root_path, "", -1,
3684 	    ".gitignore");
3685 	if (err)
3686 		return err;
3687 
3688 	err = got_path_dirname(&parent_path, path);
3689 	if (err) {
3690 		if (err->code == GOT_ERR_BAD_PATH)
3691 			return NULL; /* cannot traverse parent */
3692 		return err;
3693 	}
3694 	for (;;) {
3695 		err = add_ignores(ignores, root_path, parent_path, -1,
3696 		    ".cvsignore");
3697 		if (err)
3698 			break;
3699 		err = add_ignores(ignores, root_path, parent_path, -1,
3700 		    ".gitignore");
3701 		if (err)
3702 			break;
3703 		err = got_path_dirname(&next_parent_path, parent_path);
3704 		if (err) {
3705 			if (err->code == GOT_ERR_BAD_PATH)
3706 				err = NULL; /* traversed everything */
3707 			break;
3708 		}
3709 		if (got_path_is_root_dir(parent_path))
3710 			break;
3711 		free(parent_path);
3712 		parent_path = next_parent_path;
3713 		next_parent_path = NULL;
3714 	}
3715 
3716 	free(parent_path);
3717 	free(next_parent_path);
3718 	return err;
3719 }
3720 
3721 static const struct got_error *
3722 worktree_status(struct got_worktree *worktree, const char *path,
3723     struct got_fileindex *fileindex, struct got_repository *repo,
3724     got_worktree_status_cb status_cb, void *status_arg,
3725     got_cancel_cb cancel_cb, void *cancel_arg, int no_ignores,
3726     int report_unchanged)
3727 {
3728 	const struct got_error *err = NULL;
3729 	int fd = -1;
3730 	struct got_fileindex_diff_dir_cb fdiff_cb;
3731 	struct diff_dir_cb_arg arg;
3732 	char *ondisk_path = NULL;
3733 	struct got_pathlist_head ignores;
3734 	struct got_fileindex_entry *ie;
3735 
3736 	TAILQ_INIT(&ignores);
3737 
3738 	if (asprintf(&ondisk_path, "%s%s%s",
3739 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
3740 		return got_error_from_errno("asprintf");
3741 
3742 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3743 	if (ie) {
3744 		err = report_single_file_status(path, ondisk_path,
3745 		    fileindex, status_cb, status_arg, repo,
3746 		    report_unchanged, &ignores, no_ignores);
3747 		goto done;
3748 	}
3749 
3750 	fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC);
3751 	if (fd == -1) {
3752 		if (errno != ENOTDIR && errno != ENOENT && errno != EACCES &&
3753 		    !got_err_open_nofollow_on_symlink())
3754 			err = got_error_from_errno2("open", ondisk_path);
3755 		else {
3756 			if (!no_ignores) {
3757 				err = add_ignores_from_parent_paths(&ignores,
3758 				    worktree->root_path, ondisk_path);
3759 				if (err)
3760 					goto done;
3761 			}
3762 			err = report_single_file_status(path, ondisk_path,
3763 			    fileindex, status_cb, status_arg, repo,
3764 			    report_unchanged, &ignores, no_ignores);
3765 		}
3766 	} else {
3767 		fdiff_cb.diff_old_new = status_old_new;
3768 		fdiff_cb.diff_old = status_old;
3769 		fdiff_cb.diff_new = status_new;
3770 		fdiff_cb.diff_traverse = status_traverse;
3771 		arg.fileindex = fileindex;
3772 		arg.worktree = worktree;
3773 		arg.status_path = path;
3774 		arg.status_path_len = strlen(path);
3775 		arg.repo = repo;
3776 		arg.status_cb = status_cb;
3777 		arg.status_arg = status_arg;
3778 		arg.cancel_cb = cancel_cb;
3779 		arg.cancel_arg = cancel_arg;
3780 		arg.report_unchanged = report_unchanged;
3781 		arg.no_ignores = no_ignores;
3782 		if (!no_ignores) {
3783 			err = add_ignores_from_parent_paths(&ignores,
3784 			    worktree->root_path, path);
3785 			if (err)
3786 				goto done;
3787 		}
3788 		arg.ignores = &ignores;
3789 		err = got_fileindex_diff_dir(fileindex, fd,
3790 		    worktree->root_path, path, repo, &fdiff_cb, &arg);
3791 	}
3792 done:
3793 	free_ignores(&ignores);
3794 	if (fd != -1 && close(fd) == -1 && err == NULL)
3795 		err = got_error_from_errno("close");
3796 	free(ondisk_path);
3797 	return err;
3798 }
3799 
3800 const struct got_error *
3801 got_worktree_status(struct got_worktree *worktree,
3802     struct got_pathlist_head *paths, struct got_repository *repo,
3803     int no_ignores, got_worktree_status_cb status_cb, void *status_arg,
3804     got_cancel_cb cancel_cb, void *cancel_arg)
3805 {
3806 	const struct got_error *err = NULL;
3807 	char *fileindex_path = NULL;
3808 	struct got_fileindex *fileindex = NULL;
3809 	struct got_pathlist_entry *pe;
3810 
3811 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3812 	if (err)
3813 		return err;
3814 
3815 	TAILQ_FOREACH(pe, paths, entry) {
3816 		err = worktree_status(worktree, pe->path, fileindex, repo,
3817 			status_cb, status_arg, cancel_cb, cancel_arg,
3818 			no_ignores, 0);
3819 		if (err)
3820 			break;
3821 	}
3822 	free(fileindex_path);
3823 	got_fileindex_free(fileindex);
3824 	return err;
3825 }
3826 
3827 const struct got_error *
3828 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
3829     const char *arg)
3830 {
3831 	const struct got_error *err = NULL;
3832 	char *resolved = NULL, *cwd = NULL, *path = NULL;
3833 	size_t len;
3834 	struct stat sb;
3835 	char *abspath = NULL;
3836 	char canonpath[PATH_MAX];
3837 
3838 	*wt_path = NULL;
3839 
3840 	cwd = getcwd(NULL, 0);
3841 	if (cwd == NULL)
3842 		return got_error_from_errno("getcwd");
3843 
3844 	if (lstat(arg, &sb) == -1) {
3845 		if (errno != ENOENT) {
3846 			err = got_error_from_errno2("lstat", arg);
3847 			goto done;
3848 		}
3849 		sb.st_mode = 0;
3850 	}
3851 	if (S_ISLNK(sb.st_mode)) {
3852 		/*
3853 		 * We cannot use realpath(3) with symlinks since we want to
3854 		 * operate on the symlink itself.
3855 		 * But we can make the path absolute, assuming it is relative
3856 		 * to the current working directory, and then canonicalize it.
3857 		 */
3858 		if (!got_path_is_absolute(arg)) {
3859 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3860 				err = got_error_from_errno("asprintf");
3861 				goto done;
3862 			}
3863 
3864 		}
3865 		err = got_canonpath(abspath ? abspath : arg, canonpath,
3866 		    sizeof(canonpath));
3867 		if (err)
3868 			goto done;
3869 		resolved = strdup(canonpath);
3870 		if (resolved == NULL) {
3871 			err = got_error_from_errno("strdup");
3872 			goto done;
3873 		}
3874 	} else {
3875 		resolved = realpath(arg, NULL);
3876 		if (resolved == NULL) {
3877 			if (errno != ENOENT) {
3878 				err = got_error_from_errno2("realpath", arg);
3879 				goto done;
3880 			}
3881 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3882 				err = got_error_from_errno("asprintf");
3883 				goto done;
3884 			}
3885 			err = got_canonpath(abspath, canonpath,
3886 			    sizeof(canonpath));
3887 			if (err)
3888 				goto done;
3889 			resolved = strdup(canonpath);
3890 			if (resolved == NULL) {
3891 				err = got_error_from_errno("strdup");
3892 				goto done;
3893 			}
3894 		}
3895 	}
3896 
3897 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
3898 	    strlen(got_worktree_get_root_path(worktree)))) {
3899 		err = got_error_path(resolved, GOT_ERR_BAD_PATH);
3900 		goto done;
3901 	}
3902 
3903 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
3904 		err = got_path_skip_common_ancestor(&path,
3905 		    got_worktree_get_root_path(worktree), resolved);
3906 		if (err)
3907 			goto done;
3908 	} else {
3909 		path = strdup("");
3910 		if (path == NULL) {
3911 			err = got_error_from_errno("strdup");
3912 			goto done;
3913 		}
3914 	}
3915 
3916 	/* XXX status walk can't deal with trailing slash! */
3917 	len = strlen(path);
3918 	while (len > 0 && path[len - 1] == '/') {
3919 		path[len - 1] = '\0';
3920 		len--;
3921 	}
3922 done:
3923 	free(abspath);
3924 	free(resolved);
3925 	free(cwd);
3926 	if (err == NULL)
3927 		*wt_path = path;
3928 	else
3929 		free(path);
3930 	return err;
3931 }
3932 
3933 struct schedule_addition_args {
3934 	struct got_worktree *worktree;
3935 	struct got_fileindex *fileindex;
3936 	got_worktree_checkout_cb progress_cb;
3937 	void *progress_arg;
3938 	struct got_repository *repo;
3939 };
3940 
3941 static const struct got_error *
3942 schedule_addition(void *arg, unsigned char status, unsigned char staged_status,
3943     const char *relpath, struct got_object_id *blob_id,
3944     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
3945     int dirfd, const char *de_name)
3946 {
3947 	struct schedule_addition_args *a = arg;
3948 	const struct got_error *err = NULL;
3949 	struct got_fileindex_entry *ie;
3950 	struct stat sb;
3951 	char *ondisk_path;
3952 
3953 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
3954 	    relpath) == -1)
3955 		return got_error_from_errno("asprintf");
3956 
3957 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
3958 	if (ie) {
3959 		err = get_file_status(&status, &sb, ie, ondisk_path, dirfd,
3960 		    de_name, a->repo);
3961 		if (err)
3962 			goto done;
3963 		/* Re-adding an existing entry is a no-op. */
3964 		if (status == GOT_STATUS_ADD)
3965 			goto done;
3966 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
3967 		if (err)
3968 			goto done;
3969 	}
3970 
3971 	if (status != GOT_STATUS_UNVERSIONED) {
3972 		if (status == GOT_STATUS_NONEXISTENT)
3973 			err = got_error_set_errno(ENOENT, ondisk_path);
3974 		else
3975 			err = got_error_path(ondisk_path, GOT_ERR_FILE_STATUS);
3976 		goto done;
3977 	}
3978 
3979 	err = got_fileindex_entry_alloc(&ie, relpath);
3980 	if (err)
3981 		goto done;
3982 	err = got_fileindex_entry_update(ie, a->worktree->root_fd,
3983 	    relpath, NULL, NULL, 1);
3984 	if (err) {
3985 		got_fileindex_entry_free(ie);
3986 		goto done;
3987 	}
3988 	err = got_fileindex_entry_add(a->fileindex, ie);
3989 	if (err) {
3990 		got_fileindex_entry_free(ie);
3991 		goto done;
3992 	}
3993 done:
3994 	free(ondisk_path);
3995 	if (err)
3996 		return err;
3997 	if (status == GOT_STATUS_ADD)
3998 		return NULL;
3999 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_ADD, relpath);
4000 }
4001 
4002 const struct got_error *
4003 got_worktree_schedule_add(struct got_worktree *worktree,
4004     struct got_pathlist_head *paths,
4005     got_worktree_checkout_cb progress_cb, void *progress_arg,
4006     struct got_repository *repo, int no_ignores)
4007 {
4008 	struct got_fileindex *fileindex = NULL;
4009 	char *fileindex_path = NULL;
4010 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4011 	struct got_pathlist_entry *pe;
4012 	struct schedule_addition_args saa;
4013 
4014 	err = lock_worktree(worktree, LOCK_EX);
4015 	if (err)
4016 		return err;
4017 
4018 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4019 	if (err)
4020 		goto done;
4021 
4022 	saa.worktree = worktree;
4023 	saa.fileindex = fileindex;
4024 	saa.progress_cb = progress_cb;
4025 	saa.progress_arg = progress_arg;
4026 	saa.repo = repo;
4027 
4028 	TAILQ_FOREACH(pe, paths, entry) {
4029 		err = worktree_status(worktree, pe->path, fileindex, repo,
4030 			schedule_addition, &saa, NULL, NULL, no_ignores, 0);
4031 		if (err)
4032 			break;
4033 	}
4034 	sync_err = sync_fileindex(fileindex, fileindex_path);
4035 	if (sync_err && err == NULL)
4036 		err = sync_err;
4037 done:
4038 	free(fileindex_path);
4039 	if (fileindex)
4040 		got_fileindex_free(fileindex);
4041 	unlockerr = lock_worktree(worktree, LOCK_SH);
4042 	if (unlockerr && err == NULL)
4043 		err = unlockerr;
4044 	return err;
4045 }
4046 
4047 struct schedule_deletion_args {
4048 	struct got_worktree *worktree;
4049 	struct got_fileindex *fileindex;
4050 	got_worktree_delete_cb progress_cb;
4051 	void *progress_arg;
4052 	struct got_repository *repo;
4053 	int delete_local_mods;
4054 	int keep_on_disk;
4055 	int ignore_missing_paths;
4056 	const char *status_codes;
4057 };
4058 
4059 static const struct got_error *
4060 schedule_for_deletion(void *arg, unsigned char status,
4061     unsigned char staged_status, const char *relpath,
4062     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
4063     struct got_object_id *commit_id, int dirfd, const char *de_name)
4064 {
4065 	struct schedule_deletion_args *a = arg;
4066 	const struct got_error *err = NULL;
4067 	struct got_fileindex_entry *ie = NULL;
4068 	struct stat sb;
4069 	char *ondisk_path;
4070 
4071 	if (status == GOT_STATUS_NONEXISTENT) {
4072 		if (a->ignore_missing_paths)
4073 			return NULL;
4074 		return got_error_set_errno(ENOENT, relpath);
4075 	}
4076 
4077 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4078 	if (ie == NULL)
4079 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
4080 
4081 	staged_status = get_staged_status(ie);
4082 	if (staged_status != GOT_STATUS_NO_CHANGE) {
4083 		if (staged_status == GOT_STATUS_DELETE)
4084 			return NULL;
4085 		return got_error_path(relpath, GOT_ERR_FILE_STAGED);
4086 	}
4087 
4088 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
4089 	    relpath) == -1)
4090 		return got_error_from_errno("asprintf");
4091 
4092 	err = get_file_status(&status, &sb, ie, ondisk_path, dirfd, de_name,
4093 	    a->repo);
4094 	if (err)
4095 		goto done;
4096 
4097 	if (a->status_codes) {
4098 		size_t ncodes = strlen(a->status_codes);
4099 		int i;
4100 		for (i = 0; i < ncodes ; i++) {
4101 			if (status == a->status_codes[i])
4102 				break;
4103 		}
4104 		if (i == ncodes) {
4105 			/* Do not delete files in non-matching status. */
4106 			free(ondisk_path);
4107 			return NULL;
4108 		}
4109 		if (a->status_codes[i] != GOT_STATUS_MODIFY &&
4110 		    a->status_codes[i] != GOT_STATUS_MISSING) {
4111 			static char msg[64];
4112 			snprintf(msg, sizeof(msg),
4113 			    "invalid status code '%c'", a->status_codes[i]);
4114 			err = got_error_msg(GOT_ERR_FILE_STATUS, msg);
4115 			goto done;
4116 		}
4117 	}
4118 
4119 	if (status != GOT_STATUS_NO_CHANGE) {
4120 		if (status == GOT_STATUS_DELETE)
4121 			goto done;
4122 		if (status == GOT_STATUS_MODIFY && !a->delete_local_mods) {
4123 			err = got_error_path(relpath, GOT_ERR_FILE_MODIFIED);
4124 			goto done;
4125 		}
4126 		if (status == GOT_STATUS_MISSING && !a->ignore_missing_paths) {
4127 			err = got_error_set_errno(ENOENT, relpath);
4128 			goto done;
4129 		}
4130 		if (status != GOT_STATUS_MODIFY &&
4131 		    status != GOT_STATUS_MISSING) {
4132 			err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4133 			goto done;
4134 		}
4135 	}
4136 
4137 	if (!a->keep_on_disk && status != GOT_STATUS_MISSING) {
4138 		size_t root_len;
4139 
4140 		if (dirfd != -1) {
4141 			if (unlinkat(dirfd, de_name, 0) == -1) {
4142 				err = got_error_from_errno2("unlinkat",
4143 				    ondisk_path);
4144 				goto done;
4145 			}
4146 		} else if (unlink(ondisk_path) == -1) {
4147 			err = got_error_from_errno2("unlink", ondisk_path);
4148 			goto done;
4149 		}
4150 
4151 		root_len = strlen(a->worktree->root_path);
4152 		do {
4153 			char *parent;
4154 			err = got_path_dirname(&parent, ondisk_path);
4155 			if (err)
4156 				goto done;
4157 			free(ondisk_path);
4158 			ondisk_path = parent;
4159 			if (rmdir(ondisk_path) == -1) {
4160 				if (errno != ENOTEMPTY)
4161 					err = got_error_from_errno2("rmdir",
4162 					    ondisk_path);
4163 				break;
4164 			}
4165 		} while (got_path_cmp(ondisk_path, a->worktree->root_path,
4166 		    strlen(ondisk_path), root_len) != 0);
4167 	}
4168 
4169 	got_fileindex_entry_mark_deleted_from_disk(ie);
4170 done:
4171 	free(ondisk_path);
4172 	if (err)
4173 		return err;
4174 	if (status == GOT_STATUS_DELETE)
4175 		return NULL;
4176 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
4177 	    staged_status, relpath);
4178 }
4179 
4180 const struct got_error *
4181 got_worktree_schedule_delete(struct got_worktree *worktree,
4182     struct got_pathlist_head *paths, int delete_local_mods,
4183     const char *status_codes,
4184     got_worktree_delete_cb progress_cb, void *progress_arg,
4185     struct got_repository *repo, int keep_on_disk, int ignore_missing_paths)
4186 {
4187 	struct got_fileindex *fileindex = NULL;
4188 	char *fileindex_path = NULL;
4189 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4190 	struct got_pathlist_entry *pe;
4191 	struct schedule_deletion_args sda;
4192 
4193 	err = lock_worktree(worktree, LOCK_EX);
4194 	if (err)
4195 		return err;
4196 
4197 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4198 	if (err)
4199 		goto done;
4200 
4201 	sda.worktree = worktree;
4202 	sda.fileindex = fileindex;
4203 	sda.progress_cb = progress_cb;
4204 	sda.progress_arg = progress_arg;
4205 	sda.repo = repo;
4206 	sda.delete_local_mods = delete_local_mods;
4207 	sda.keep_on_disk = keep_on_disk;
4208 	sda.ignore_missing_paths = ignore_missing_paths;
4209 	sda.status_codes = status_codes;
4210 
4211 	TAILQ_FOREACH(pe, paths, entry) {
4212 		err = worktree_status(worktree, pe->path, fileindex, repo,
4213 			schedule_for_deletion, &sda, NULL, NULL, 1, 1);
4214 		if (err)
4215 			break;
4216 	}
4217 	sync_err = sync_fileindex(fileindex, fileindex_path);
4218 	if (sync_err && err == NULL)
4219 		err = sync_err;
4220 done:
4221 	free(fileindex_path);
4222 	if (fileindex)
4223 		got_fileindex_free(fileindex);
4224 	unlockerr = lock_worktree(worktree, LOCK_SH);
4225 	if (unlockerr && err == NULL)
4226 		err = unlockerr;
4227 	return err;
4228 }
4229 
4230 static const struct got_error *
4231 copy_one_line(FILE *infile, FILE *outfile, FILE *rejectfile)
4232 {
4233 	const struct got_error *err = NULL;
4234 	char *line = NULL;
4235 	size_t linesize = 0, n;
4236 	ssize_t linelen;
4237 
4238 	linelen = getline(&line, &linesize, infile);
4239 	if (linelen == -1) {
4240 		if (ferror(infile)) {
4241 			err = got_error_from_errno("getline");
4242 			goto done;
4243 		}
4244 		return NULL;
4245 	}
4246 	if (outfile) {
4247 		n = fwrite(line, 1, linelen, outfile);
4248 		if (n != linelen) {
4249 			err = got_ferror(outfile, GOT_ERR_IO);
4250 			goto done;
4251 		}
4252 	}
4253 	if (rejectfile) {
4254 		n = fwrite(line, 1, linelen, rejectfile);
4255 		if (n != linelen)
4256 			err = got_ferror(rejectfile, GOT_ERR_IO);
4257 	}
4258 done:
4259 	free(line);
4260 	return err;
4261 }
4262 
4263 static const struct got_error *
4264 skip_one_line(FILE *f)
4265 {
4266 	char *line = NULL;
4267 	size_t linesize = 0;
4268 	ssize_t linelen;
4269 
4270 	linelen = getline(&line, &linesize, f);
4271 	if (linelen == -1) {
4272 		if (ferror(f))
4273 			return got_error_from_errno("getline");
4274 		return NULL;
4275 	}
4276 	free(line);
4277 	return NULL;
4278 }
4279 
4280 static const struct got_error *
4281 copy_change(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4282     int start_old, int end_old, int start_new, int end_new,
4283     FILE *outfile, FILE *rejectfile)
4284 {
4285 	const struct got_error *err;
4286 
4287 	/* Copy old file's lines leading up to patch. */
4288 	while (!feof(f1) && *line_cur1 < start_old) {
4289 		err = copy_one_line(f1, outfile, NULL);
4290 		if (err)
4291 			return err;
4292 		(*line_cur1)++;
4293 	}
4294 	/* Skip new file's lines leading up to patch. */
4295 	while (!feof(f2) && *line_cur2 < start_new) {
4296 		if (rejectfile)
4297 			err = copy_one_line(f2, NULL, rejectfile);
4298 		else
4299 			err = skip_one_line(f2);
4300 		if (err)
4301 			return err;
4302 		(*line_cur2)++;
4303 	}
4304 	/* Copy patched lines. */
4305 	while (!feof(f2) && *line_cur2 <= end_new) {
4306 		err = copy_one_line(f2, outfile, NULL);
4307 		if (err)
4308 			return err;
4309 		(*line_cur2)++;
4310 	}
4311 	/* Skip over old file's replaced lines. */
4312 	while (!feof(f1) && *line_cur1 <= end_old) {
4313 		if (rejectfile)
4314 			err = copy_one_line(f1, NULL, rejectfile);
4315 		else
4316 			err = skip_one_line(f1);
4317 		if (err)
4318 			return err;
4319 		(*line_cur1)++;
4320 	}
4321 
4322 	return NULL;
4323 }
4324 
4325 static const struct got_error *
4326 copy_remaining_content(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4327     FILE *outfile, FILE *rejectfile)
4328 {
4329 	const struct got_error *err;
4330 
4331 	if (outfile) {
4332 		/* Copy old file's lines until EOF. */
4333 		while (!feof(f1)) {
4334 			err = copy_one_line(f1, outfile, NULL);
4335 			if (err)
4336 				return err;
4337 			(*line_cur1)++;
4338 		}
4339 	}
4340 	if (rejectfile) {
4341 		/* Copy new file's lines until EOF. */
4342 		while (!feof(f2)) {
4343 			err = copy_one_line(f2, NULL, rejectfile);
4344 			if (err)
4345 				return err;
4346 			(*line_cur2)++;
4347 		}
4348 	}
4349 
4350 	return NULL;
4351 }
4352 
4353 static const struct got_error *
4354 apply_or_reject_change(int *choice, int *nchunks_used,
4355     struct diff_result *diff_result, int n,
4356     const char *relpath, FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4357     FILE *outfile, FILE *rejectfile, int changeno, int nchanges,
4358     got_worktree_patch_cb patch_cb, void *patch_arg)
4359 {
4360 	const struct got_error *err = NULL;
4361 	struct diff_chunk_context cc = {};
4362 	int start_old, end_old, start_new, end_new;
4363 	FILE *hunkfile;
4364 	struct diff_output_unidiff_state *diff_state;
4365 	struct diff_input_info diff_info;
4366 	int rc;
4367 
4368 	*choice = GOT_PATCH_CHOICE_NONE;
4369 
4370 	/* Get changed line numbers without context lines for copy_change(). */
4371 	diff_chunk_context_load_change(&cc, NULL, diff_result, n, 0);
4372 	start_old = cc.left.start;
4373 	end_old = cc.left.end;
4374 	start_new = cc.right.start;
4375 	end_new = cc.right.end;
4376 
4377 	/* Get the same change with context lines for display. */
4378 	memset(&cc, 0, sizeof(cc));
4379 	diff_chunk_context_load_change(&cc, nchunks_used, diff_result, n, 3);
4380 
4381 	memset(&diff_info, 0, sizeof(diff_info));
4382 	diff_info.left_path = relpath;
4383 	diff_info.right_path = relpath;
4384 
4385 	diff_state = diff_output_unidiff_state_alloc();
4386 	if (diff_state == NULL)
4387 		return got_error_set_errno(ENOMEM,
4388 		    "diff_output_unidiff_state_alloc");
4389 
4390 	hunkfile = got_opentemp();
4391 	if (hunkfile == NULL) {
4392 		err = got_error_from_errno("got_opentemp");
4393 		goto done;
4394 	}
4395 
4396 	rc = diff_output_unidiff_chunk(NULL, hunkfile, diff_state, &diff_info,
4397 	    diff_result, &cc);
4398 	if (rc != DIFF_RC_OK) {
4399 		err = got_error_set_errno(rc, "diff_output_unidiff_chunk");
4400 		goto done;
4401 	}
4402 
4403 	if (fseek(hunkfile, 0L, SEEK_SET) == -1) {
4404 		err = got_ferror(hunkfile, GOT_ERR_IO);
4405 		goto done;
4406 	}
4407 
4408 	err = (*patch_cb)(choice, patch_arg, GOT_STATUS_MODIFY, relpath,
4409 	    hunkfile, changeno, nchanges);
4410 	if (err)
4411 		goto done;
4412 
4413 	switch (*choice) {
4414 	case GOT_PATCH_CHOICE_YES:
4415 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4416 		    end_old, start_new, end_new, outfile, rejectfile);
4417 		break;
4418 	case GOT_PATCH_CHOICE_NO:
4419 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4420 		    end_old, start_new, end_new, rejectfile, outfile);
4421 		break;
4422 	case GOT_PATCH_CHOICE_QUIT:
4423 		break;
4424 	default:
4425 		err = got_error(GOT_ERR_PATCH_CHOICE);
4426 		break;
4427 	}
4428 done:
4429 	diff_output_unidiff_state_free(diff_state);
4430 	if (hunkfile && fclose(hunkfile) == EOF && err == NULL)
4431 		err = got_error_from_errno("fclose");
4432 	return err;
4433 }
4434 
4435 struct revert_file_args {
4436 	struct got_worktree *worktree;
4437 	struct got_fileindex *fileindex;
4438 	got_worktree_checkout_cb progress_cb;
4439 	void *progress_arg;
4440 	got_worktree_patch_cb patch_cb;
4441 	void *patch_arg;
4442 	struct got_repository *repo;
4443 	int unlink_added_files;
4444 };
4445 
4446 static const struct got_error *
4447 create_patched_content(char **path_outfile, int reverse_patch,
4448     struct got_object_id *blob_id, const char *path2,
4449     int dirfd2, const char *de_name2,
4450     const char *relpath, struct got_repository *repo,
4451     got_worktree_patch_cb patch_cb, void *patch_arg)
4452 {
4453 	const struct got_error *err, *free_err;
4454 	struct got_blob_object *blob = NULL;
4455 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL;
4456 	int fd = -1, fd2 = -1;
4457 	char link_target[PATH_MAX];
4458 	ssize_t link_len = 0;
4459 	char *path1 = NULL, *id_str = NULL;
4460 	struct stat sb2;
4461 	struct got_diffreg_result *diffreg_result = NULL;
4462 	int line_cur1 = 1, line_cur2 = 1, have_content = 0;
4463 	int i = 0, n = 0, nchunks_used = 0, nchanges = 0;
4464 
4465 	*path_outfile = NULL;
4466 
4467 	err = got_object_id_str(&id_str, blob_id);
4468 	if (err)
4469 		return err;
4470 
4471 	if (dirfd2 != -1) {
4472 		fd2 = openat(dirfd2, de_name2,
4473 		    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
4474 		if (fd2 == -1) {
4475 			if (!got_err_open_nofollow_on_symlink()) {
4476 				err = got_error_from_errno2("openat", path2);
4477 				goto done;
4478 			}
4479 			link_len = readlinkat(dirfd2, de_name2,
4480 			    link_target, sizeof(link_target));
4481 			if (link_len == -1) {
4482 				return got_error_from_errno2("readlinkat",
4483 				    path2);
4484 			}
4485 			sb2.st_mode = S_IFLNK;
4486 			sb2.st_size = link_len;
4487 		}
4488 	} else {
4489 		fd2 = open(path2, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
4490 		if (fd2 == -1) {
4491 			if (!got_err_open_nofollow_on_symlink()) {
4492 				err = got_error_from_errno2("open", path2);
4493 				goto done;
4494 			}
4495 			link_len = readlink(path2, link_target,
4496 			    sizeof(link_target));
4497 			if (link_len == -1)
4498 				return got_error_from_errno2("readlink", path2);
4499 			sb2.st_mode = S_IFLNK;
4500 			sb2.st_size = link_len;
4501 		}
4502 	}
4503 	if (fd2 != -1) {
4504 		if (fstat(fd2, &sb2) == -1) {
4505 			err = got_error_from_errno2("fstat", path2);
4506 			goto done;
4507 		}
4508 
4509 		f2 = fdopen(fd2, "r");
4510 		if (f2 == NULL) {
4511 			err = got_error_from_errno2("fdopen", path2);
4512 			goto done;
4513 		}
4514 		fd2 = -1;
4515 	} else {
4516 		size_t n;
4517 		f2 = got_opentemp();
4518 		if (f2 == NULL) {
4519 			err = got_error_from_errno2("got_opentemp", path2);
4520 			goto done;
4521 		}
4522 		n = fwrite(link_target, 1, link_len, f2);
4523 		if (n != link_len) {
4524 			err = got_ferror(f2, GOT_ERR_IO);
4525 			goto done;
4526 		}
4527 		if (fflush(f2) == EOF) {
4528 			err = got_error_from_errno("fflush");
4529 			goto done;
4530 		}
4531 		rewind(f2);
4532 	}
4533 
4534 	fd = got_opentempfd();
4535 	if (fd == -1) {
4536 		err = got_error_from_errno("got_opentempfd");
4537 		goto done;
4538 	}
4539 
4540 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192, fd);
4541 	if (err)
4542 		goto done;
4543 
4544 	err = got_opentemp_named(&path1, &f1, "got-patched-blob", "");
4545 	if (err)
4546 		goto done;
4547 
4548 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
4549 	if (err)
4550 		goto done;
4551 
4552 	err = got_diff_files(&diffreg_result, f1, 1, id_str, f2, 1, path2,
4553 	    3, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
4554 	if (err)
4555 		goto done;
4556 
4557 	err = got_opentemp_named(path_outfile, &outfile, "got-patched-content",
4558 	    "");
4559 	if (err)
4560 		goto done;
4561 
4562 	if (fseek(f1, 0L, SEEK_SET) == -1)
4563 		return got_ferror(f1, GOT_ERR_IO);
4564 	if (fseek(f2, 0L, SEEK_SET) == -1)
4565 		return got_ferror(f2, GOT_ERR_IO);
4566 
4567 	/* Count the number of actual changes in the diff result. */
4568 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4569 		struct diff_chunk_context cc = {};
4570 		diff_chunk_context_load_change(&cc, &nchunks_used,
4571 		    diffreg_result->result, n, 0);
4572 		nchanges++;
4573 	}
4574 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4575 		int choice;
4576 		err = apply_or_reject_change(&choice, &nchunks_used,
4577 		    diffreg_result->result, n, relpath, f1, f2,
4578 		    &line_cur1, &line_cur2,
4579 		    reverse_patch ? NULL : outfile,
4580 		    reverse_patch ? outfile : NULL,
4581 		    ++i, nchanges, patch_cb, patch_arg);
4582 		if (err)
4583 			goto done;
4584 		if (choice == GOT_PATCH_CHOICE_YES)
4585 			have_content = 1;
4586 		else if (choice == GOT_PATCH_CHOICE_QUIT)
4587 			break;
4588 	}
4589 	if (have_content) {
4590 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
4591 		    reverse_patch ? NULL : outfile,
4592 		    reverse_patch ? outfile : NULL);
4593 		if (err)
4594 			goto done;
4595 
4596 		if (!S_ISLNK(sb2.st_mode)) {
4597 			mode_t mode;
4598 
4599 			mode = apply_umask(sb2.st_mode);
4600 			if (fchmod(fileno(outfile), mode) == -1) {
4601 				err = got_error_from_errno2("fchmod", path2);
4602 				goto done;
4603 			}
4604 		}
4605 	}
4606 done:
4607 	free(id_str);
4608 	if (fd != -1 && close(fd) == -1 && err == NULL)
4609 		err = got_error_from_errno("close");
4610 	if (blob)
4611 		got_object_blob_close(blob);
4612 	free_err = got_diffreg_result_free(diffreg_result);
4613 	if (err == NULL)
4614 		err = free_err;
4615 	if (f1 && fclose(f1) == EOF && err == NULL)
4616 		err = got_error_from_errno2("fclose", path1);
4617 	if (f2 && fclose(f2) == EOF && err == NULL)
4618 		err = got_error_from_errno2("fclose", path2);
4619 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
4620 		err = got_error_from_errno2("close", path2);
4621 	if (outfile && fclose(outfile) == EOF && err == NULL)
4622 		err = got_error_from_errno2("fclose", *path_outfile);
4623 	if (path1 && unlink(path1) == -1 && err == NULL)
4624 		err = got_error_from_errno2("unlink", path1);
4625 	if (err || !have_content) {
4626 		if (*path_outfile && unlink(*path_outfile) == -1 && err == NULL)
4627 			err = got_error_from_errno2("unlink", *path_outfile);
4628 		free(*path_outfile);
4629 		*path_outfile = NULL;
4630 	}
4631 	free(path1);
4632 	return err;
4633 }
4634 
4635 static const struct got_error *
4636 revert_file(void *arg, unsigned char status, unsigned char staged_status,
4637     const char *relpath, struct got_object_id *blob_id,
4638     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
4639     int dirfd, const char *de_name)
4640 {
4641 	struct revert_file_args *a = arg;
4642 	const struct got_error *err = NULL;
4643 	char *parent_path = NULL;
4644 	struct got_fileindex_entry *ie;
4645 	struct got_commit_object *base_commit = NULL;
4646 	struct got_tree_object *tree = NULL;
4647 	struct got_object_id *tree_id = NULL;
4648 	const struct got_tree_entry *te = NULL;
4649 	char *tree_path = NULL, *te_name;
4650 	char *ondisk_path = NULL, *path_content = NULL;
4651 	struct got_blob_object *blob = NULL;
4652 	int fd = -1;
4653 
4654 	/* Reverting a staged deletion is a no-op. */
4655 	if (status == GOT_STATUS_DELETE &&
4656 	    staged_status != GOT_STATUS_NO_CHANGE)
4657 		return NULL;
4658 
4659 	if (status == GOT_STATUS_UNVERSIONED)
4660 		return (*a->progress_cb)(a->progress_arg,
4661 		    GOT_STATUS_UNVERSIONED, relpath);
4662 
4663 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4664 	if (ie == NULL)
4665 		return got_error_path(relpath, GOT_ERR_BAD_PATH);
4666 
4667 	/* Construct in-repository path of tree which contains this blob. */
4668 	err = got_path_dirname(&parent_path, ie->path);
4669 	if (err) {
4670 		if (err->code != GOT_ERR_BAD_PATH)
4671 			goto done;
4672 		parent_path = strdup("/");
4673 		if (parent_path == NULL) {
4674 			err = got_error_from_errno("strdup");
4675 			goto done;
4676 		}
4677 	}
4678 	if (got_path_is_root_dir(a->worktree->path_prefix)) {
4679 		tree_path = strdup(parent_path);
4680 		if (tree_path == NULL) {
4681 			err = got_error_from_errno("strdup");
4682 			goto done;
4683 		}
4684 	} else {
4685 		if (got_path_is_root_dir(parent_path)) {
4686 			tree_path = strdup(a->worktree->path_prefix);
4687 			if (tree_path == NULL) {
4688 				err = got_error_from_errno("strdup");
4689 				goto done;
4690 			}
4691 		} else {
4692 			if (asprintf(&tree_path, "%s/%s",
4693 			    a->worktree->path_prefix, parent_path) == -1) {
4694 				err = got_error_from_errno("asprintf");
4695 				goto done;
4696 			}
4697 		}
4698 	}
4699 
4700 	err = got_object_open_as_commit(&base_commit, a->repo,
4701 	    a->worktree->base_commit_id);
4702 	if (err)
4703 		goto done;
4704 
4705 	err = got_object_id_by_path(&tree_id, a->repo, base_commit, tree_path);
4706 	if (err) {
4707 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
4708 		    (status == GOT_STATUS_ADD ||
4709 		    staged_status == GOT_STATUS_ADD)))
4710 			goto done;
4711 	} else {
4712 		err = got_object_open_as_tree(&tree, a->repo, tree_id);
4713 		if (err)
4714 			goto done;
4715 
4716 		err = got_path_basename(&te_name, ie->path);
4717 		if (err)
4718 			goto done;
4719 
4720 		te = got_object_tree_find_entry(tree, te_name);
4721 		free(te_name);
4722 		if (te == NULL && status != GOT_STATUS_ADD &&
4723 		    staged_status != GOT_STATUS_ADD) {
4724 			err = got_error_path(ie->path, GOT_ERR_NO_TREE_ENTRY);
4725 			goto done;
4726 		}
4727 	}
4728 
4729 	switch (status) {
4730 	case GOT_STATUS_ADD:
4731 		if (a->patch_cb) {
4732 			int choice = GOT_PATCH_CHOICE_NONE;
4733 			err = (*a->patch_cb)(&choice, a->patch_arg,
4734 			    status, ie->path, NULL, 1, 1);
4735 			if (err)
4736 				goto done;
4737 			if (choice != GOT_PATCH_CHOICE_YES)
4738 				break;
4739 		}
4740 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_REVERT,
4741 		    ie->path);
4742 		if (err)
4743 			goto done;
4744 		got_fileindex_entry_remove(a->fileindex, ie);
4745 		if (a->unlink_added_files) {
4746 			if (asprintf(&ondisk_path, "%s/%s",
4747 			    got_worktree_get_root_path(a->worktree),
4748 			    relpath) == -1) {
4749 				err = got_error_from_errno("asprintf");
4750 				goto done;
4751 			}
4752 			if (unlink(ondisk_path) == -1) {
4753 				err = got_error_from_errno2("unlink",
4754 				    ondisk_path);
4755 				break;
4756 			}
4757 		}
4758 		break;
4759 	case GOT_STATUS_DELETE:
4760 		if (a->patch_cb) {
4761 			int choice = GOT_PATCH_CHOICE_NONE;
4762 			err = (*a->patch_cb)(&choice, a->patch_arg,
4763 			    status, ie->path, NULL, 1, 1);
4764 			if (err)
4765 				goto done;
4766 			if (choice != GOT_PATCH_CHOICE_YES)
4767 				break;
4768 		}
4769 		/* fall through */
4770 	case GOT_STATUS_MODIFY:
4771 	case GOT_STATUS_MODE_CHANGE:
4772 	case GOT_STATUS_CONFLICT:
4773 	case GOT_STATUS_MISSING: {
4774 		struct got_object_id id;
4775 		if (staged_status == GOT_STATUS_ADD ||
4776 		    staged_status == GOT_STATUS_MODIFY) {
4777 			memcpy(id.sha1, ie->staged_blob_sha1,
4778 			    SHA1_DIGEST_LENGTH);
4779 		} else
4780 			memcpy(id.sha1, ie->blob_sha1,
4781 			    SHA1_DIGEST_LENGTH);
4782 		fd = got_opentempfd();
4783 		if (fd == -1) {
4784 			err = got_error_from_errno("got_opentempfd");
4785 			goto done;
4786 		}
4787 
4788 		err = got_object_open_as_blob(&blob, a->repo, &id, 8192, fd);
4789 		if (err)
4790 			goto done;
4791 
4792 		if (asprintf(&ondisk_path, "%s/%s",
4793 		    got_worktree_get_root_path(a->worktree), relpath) == -1) {
4794 			err = got_error_from_errno("asprintf");
4795 			goto done;
4796 		}
4797 
4798 		if (a->patch_cb && (status == GOT_STATUS_MODIFY ||
4799 		    status == GOT_STATUS_CONFLICT)) {
4800 			int is_bad_symlink = 0;
4801 			err = create_patched_content(&path_content, 1, &id,
4802 			    ondisk_path, dirfd, de_name, ie->path, a->repo,
4803 			    a->patch_cb, a->patch_arg);
4804 			if (err || path_content == NULL)
4805 				break;
4806 			if (te && S_ISLNK(te->mode)) {
4807 				if (unlink(path_content) == -1) {
4808 					err = got_error_from_errno2("unlink",
4809 					    path_content);
4810 					break;
4811 				}
4812 				err = install_symlink(&is_bad_symlink,
4813 				    a->worktree, ondisk_path, ie->path,
4814 				    blob, 0, 1, 0, 0, a->repo,
4815 				    a->progress_cb, a->progress_arg);
4816 			} else {
4817 				if (rename(path_content, ondisk_path) == -1) {
4818 					err = got_error_from_errno3("rename",
4819 					    path_content, ondisk_path);
4820 					goto done;
4821 				}
4822 			}
4823 		} else {
4824 			int is_bad_symlink = 0;
4825 			if (te && S_ISLNK(te->mode)) {
4826 				err = install_symlink(&is_bad_symlink,
4827 				    a->worktree, ondisk_path, ie->path,
4828 				    blob, 0, 1, 0, 0, a->repo,
4829 				    a->progress_cb, a->progress_arg);
4830 			} else {
4831 				err = install_blob(a->worktree, ondisk_path,
4832 				    ie->path,
4833 				    te ? te->mode : GOT_DEFAULT_FILE_MODE,
4834 				    got_fileindex_perms_to_st(ie), blob,
4835 				    0, 1, 0, 0, a->repo,
4836 				    a->progress_cb, a->progress_arg);
4837 			}
4838 			if (err)
4839 				goto done;
4840 			if (status == GOT_STATUS_DELETE ||
4841 			    status == GOT_STATUS_MODE_CHANGE) {
4842 				err = got_fileindex_entry_update(ie,
4843 				    a->worktree->root_fd, relpath,
4844 				    blob->id.sha1,
4845 				    a->worktree->base_commit_id->sha1, 1);
4846 				if (err)
4847 					goto done;
4848 			}
4849 			if (is_bad_symlink) {
4850 				got_fileindex_entry_filetype_set(ie,
4851 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
4852 			}
4853 		}
4854 		break;
4855 	}
4856 	default:
4857 		break;
4858 	}
4859 done:
4860 	free(ondisk_path);
4861 	free(path_content);
4862 	free(parent_path);
4863 	free(tree_path);
4864 	if (fd != -1 && close(fd) == -1 && err == NULL)
4865 		err = got_error_from_errno("close");
4866 	if (blob)
4867 		got_object_blob_close(blob);
4868 	if (tree)
4869 		got_object_tree_close(tree);
4870 	free(tree_id);
4871 	if (base_commit)
4872 		got_object_commit_close(base_commit);
4873 	return err;
4874 }
4875 
4876 const struct got_error *
4877 got_worktree_revert(struct got_worktree *worktree,
4878     struct got_pathlist_head *paths,
4879     got_worktree_checkout_cb progress_cb, void *progress_arg,
4880     got_worktree_patch_cb patch_cb, void *patch_arg,
4881     struct got_repository *repo)
4882 {
4883 	struct got_fileindex *fileindex = NULL;
4884 	char *fileindex_path = NULL;
4885 	const struct got_error *err = NULL, *unlockerr = NULL;
4886 	const struct got_error *sync_err = NULL;
4887 	struct got_pathlist_entry *pe;
4888 	struct revert_file_args rfa;
4889 
4890 	err = lock_worktree(worktree, LOCK_EX);
4891 	if (err)
4892 		return err;
4893 
4894 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4895 	if (err)
4896 		goto done;
4897 
4898 	rfa.worktree = worktree;
4899 	rfa.fileindex = fileindex;
4900 	rfa.progress_cb = progress_cb;
4901 	rfa.progress_arg = progress_arg;
4902 	rfa.patch_cb = patch_cb;
4903 	rfa.patch_arg = patch_arg;
4904 	rfa.repo = repo;
4905 	rfa.unlink_added_files = 0;
4906 	TAILQ_FOREACH(pe, paths, entry) {
4907 		err = worktree_status(worktree, pe->path, fileindex, repo,
4908 		    revert_file, &rfa, NULL, NULL, 1, 0);
4909 		if (err)
4910 			break;
4911 	}
4912 	sync_err = sync_fileindex(fileindex, fileindex_path);
4913 	if (sync_err && err == NULL)
4914 		err = sync_err;
4915 done:
4916 	free(fileindex_path);
4917 	if (fileindex)
4918 		got_fileindex_free(fileindex);
4919 	unlockerr = lock_worktree(worktree, LOCK_SH);
4920 	if (unlockerr && err == NULL)
4921 		err = unlockerr;
4922 	return err;
4923 }
4924 
4925 static void
4926 free_commitable(struct got_commitable *ct)
4927 {
4928 	free(ct->path);
4929 	free(ct->in_repo_path);
4930 	free(ct->ondisk_path);
4931 	free(ct->blob_id);
4932 	free(ct->base_blob_id);
4933 	free(ct->staged_blob_id);
4934 	free(ct->base_commit_id);
4935 	free(ct);
4936 }
4937 
4938 struct collect_commitables_arg {
4939 	struct got_pathlist_head *commitable_paths;
4940 	struct got_repository *repo;
4941 	struct got_worktree *worktree;
4942 	struct got_fileindex *fileindex;
4943 	int have_staged_files;
4944 	int allow_bad_symlinks;
4945 	int diff_header_shown;
4946 	FILE *diff_outfile;
4947 	FILE *f1;
4948 	FILE *f2;
4949 };
4950 
4951 /*
4952  * Create a file which contains the target path of a symlink so we can feed
4953  * it as content to the diff engine.
4954  */
4955 static const struct got_error *
4956 get_symlink_target_file(int *fd, int dirfd, const char *de_name,
4957     const char *abspath)
4958 {
4959 	const struct got_error *err = NULL;
4960 	char target_path[PATH_MAX];
4961 	ssize_t target_len, outlen;
4962 
4963 	*fd = -1;
4964 
4965 	if (dirfd != -1) {
4966 		target_len = readlinkat(dirfd, de_name, target_path, PATH_MAX);
4967 		if (target_len == -1)
4968 			return got_error_from_errno2("readlinkat", abspath);
4969 	} else {
4970 		target_len = readlink(abspath, target_path, PATH_MAX);
4971 		if (target_len == -1)
4972 			return got_error_from_errno2("readlink", abspath);
4973 	}
4974 
4975 	*fd = got_opentempfd();
4976 	if (*fd == -1)
4977 		return got_error_from_errno("got_opentempfd");
4978 
4979 	outlen = write(*fd, target_path, target_len);
4980 	if (outlen == -1) {
4981 		err = got_error_from_errno("got_opentempfd");
4982 		goto done;
4983 	}
4984 
4985 	if (lseek(*fd, 0, SEEK_SET) == -1) {
4986 		err = got_error_from_errno2("lseek", abspath);
4987 		goto done;
4988 	}
4989 done:
4990 	if (err) {
4991 		close(*fd);
4992 		*fd = -1;
4993 	}
4994 	return err;
4995 }
4996 
4997 static const struct got_error *
4998 append_ct_diff(struct got_commitable *ct, int *diff_header_shown,
4999     FILE *diff_outfile, FILE *f1, FILE *f2, int dirfd, const char *de_name,
5000     int diff_staged, struct got_repository *repo, struct got_worktree *worktree)
5001 {
5002 	const struct got_error *err = NULL;
5003 	struct got_blob_object *blob1 = NULL;
5004 	int fd = -1, fd1 = -1, fd2 = -1;
5005 	FILE *ondisk_file = NULL;
5006 	char *label1 = NULL;
5007 	struct stat sb;
5008 	off_t size1 = 0;
5009 	int f2_exists = 0;
5010 	char *id_str = NULL;
5011 
5012 	memset(&sb, 0, sizeof(sb));
5013 
5014 	if (diff_staged) {
5015 		if (ct->staged_status != GOT_STATUS_MODIFY &&
5016 		    ct->staged_status != GOT_STATUS_ADD &&
5017 		    ct->staged_status != GOT_STATUS_DELETE)
5018 			return NULL;
5019 	} else {
5020 		if (ct->status != GOT_STATUS_MODIFY &&
5021 		    ct->status != GOT_STATUS_ADD &&
5022 		    ct->status != GOT_STATUS_DELETE)
5023 			return NULL;
5024 	}
5025 
5026 	err = got_opentemp_truncate(f1);
5027 	if (err)
5028 		return got_error_from_errno("got_opentemp_truncate");
5029 	err = got_opentemp_truncate(f2);
5030 	if (err)
5031 		return got_error_from_errno("got_opentemp_truncate");
5032 
5033 	if (!*diff_header_shown) {
5034 		err = got_object_id_str(&id_str, worktree->base_commit_id);
5035 		if (err)
5036 			return err;
5037 		fprintf(diff_outfile, "diff %s%s\n", diff_staged ? "-s " : "",
5038 		    got_worktree_get_root_path(worktree));
5039 		fprintf(diff_outfile, "commit - %s\n", id_str);
5040 		fprintf(diff_outfile, "path + %s%s\n",
5041 		    got_worktree_get_root_path(worktree),
5042 		    diff_staged ? " (staged changes)" : "");
5043 		*diff_header_shown = 1;
5044 	}
5045 
5046 	if (diff_staged) {
5047 		const char *label1 = NULL, *label2 = NULL;
5048 		switch (ct->staged_status) {
5049 		case GOT_STATUS_MODIFY:
5050 			label1 = ct->path;
5051 			label2 = ct->path;
5052 			break;
5053 		case GOT_STATUS_ADD:
5054 			label2 = ct->path;
5055 			break;
5056 		case GOT_STATUS_DELETE:
5057 			label1 = ct->path;
5058 			break;
5059 		default:
5060 			return got_error(GOT_ERR_FILE_STATUS);
5061 		}
5062 		fd1 = got_opentempfd();
5063 		if (fd1 == -1) {
5064 			err = got_error_from_errno("got_opentempfd");
5065 			goto done;
5066 		}
5067 		fd2 = got_opentempfd();
5068 		if (fd2 == -1) {
5069 			err = got_error_from_errno("got_opentempfd");
5070 			goto done;
5071 		}
5072 		err = got_diff_objects_as_blobs(NULL, NULL, f1, f2,
5073 		    fd1, fd2, ct->base_blob_id, ct->staged_blob_id,
5074 		    label1, label2, GOT_DIFF_ALGORITHM_PATIENCE, 3, 0, 0,
5075 		    NULL, repo, diff_outfile);
5076 		goto done;
5077 	}
5078 
5079 	fd1 = got_opentempfd();
5080 	if (fd1 == -1) {
5081 		err = got_error_from_errno("got_opentempfd");
5082 		goto done;
5083 	}
5084 
5085 	if (ct->status != GOT_STATUS_ADD) {
5086 		err = got_object_open_as_blob(&blob1, repo, ct->base_blob_id,
5087 		    8192, fd1);
5088 		if (err)
5089 			goto done;
5090 	}
5091 
5092 	if (ct->status != GOT_STATUS_DELETE) {
5093 		if (dirfd != -1) {
5094 			fd = openat(dirfd, de_name,
5095 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
5096 			if (fd == -1) {
5097 				if (!got_err_open_nofollow_on_symlink()) {
5098 					err = got_error_from_errno2("openat",
5099 					    ct->ondisk_path);
5100 					goto done;
5101 				}
5102 				err = get_symlink_target_file(&fd, dirfd,
5103 				    de_name, ct->ondisk_path);
5104 				if (err)
5105 					goto done;
5106 			}
5107 		} else {
5108 			fd = open(ct->ondisk_path,
5109 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
5110 			if (fd == -1) {
5111 				if (!got_err_open_nofollow_on_symlink()) {
5112 					err = got_error_from_errno2("open",
5113 					    ct->ondisk_path);
5114 					goto done;
5115 				}
5116 				err = get_symlink_target_file(&fd, dirfd,
5117 				    de_name, ct->ondisk_path);
5118 				if (err)
5119 					goto done;
5120 			}
5121 		}
5122 		if (fstatat(fd, ct->ondisk_path, &sb,
5123 		    AT_SYMLINK_NOFOLLOW) == -1) {
5124 			err = got_error_from_errno2("fstatat", ct->ondisk_path);
5125 			goto done;
5126 		}
5127 		ondisk_file = fdopen(fd, "r");
5128 		if (ondisk_file == NULL) {
5129 			err = got_error_from_errno2("fdopen", ct->ondisk_path);
5130 			goto done;
5131 		}
5132 		fd = -1;
5133 		f2_exists = 1;
5134 	}
5135 
5136 	if (blob1) {
5137 		err = got_object_blob_dump_to_file(&size1, NULL, NULL,
5138 		    f1, blob1);
5139 		if (err)
5140 			goto done;
5141 	}
5142 
5143 	err = got_diff_blob_file(blob1, f1, size1, label1,
5144 	    ondisk_file ? ondisk_file : f2, f2_exists, &sb, ct->path,
5145 	    GOT_DIFF_ALGORITHM_PATIENCE, 3, 0, 0, NULL, diff_outfile);
5146 done:
5147 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
5148 		err = got_error_from_errno("close");
5149 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
5150 		err = got_error_from_errno("close");
5151 	if (blob1)
5152 		got_object_blob_close(blob1);
5153 	if (fd != -1 && close(fd) == -1 && err == NULL)
5154 		err = got_error_from_errno("close");
5155 	if (ondisk_file && fclose(ondisk_file) == EOF && err == NULL)
5156 		err = got_error_from_errno("fclose");
5157 	return err;
5158 }
5159 
5160 static const struct got_error *
5161 collect_commitables(void *arg, unsigned char status,
5162     unsigned char staged_status, const char *relpath,
5163     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
5164     struct got_object_id *commit_id, int dirfd, const char *de_name)
5165 {
5166 	struct collect_commitables_arg *a = arg;
5167 	const struct got_error *err = NULL;
5168 	struct got_commitable *ct = NULL;
5169 	struct got_pathlist_entry *new = NULL;
5170 	char *parent_path = NULL, *path = NULL;
5171 	struct stat sb;
5172 
5173 	if (a->have_staged_files) {
5174 		if (staged_status != GOT_STATUS_MODIFY &&
5175 		    staged_status != GOT_STATUS_ADD &&
5176 		    staged_status != GOT_STATUS_DELETE)
5177 			return NULL;
5178 	} else {
5179 		if (status == GOT_STATUS_CONFLICT)
5180 			return got_error(GOT_ERR_COMMIT_CONFLICT);
5181 
5182 		if (status != GOT_STATUS_MODIFY &&
5183 		    status != GOT_STATUS_MODE_CHANGE &&
5184 		    status != GOT_STATUS_ADD &&
5185 		    status != GOT_STATUS_DELETE)
5186 			return NULL;
5187 	}
5188 
5189 	if (asprintf(&path, "/%s", relpath) == -1) {
5190 		err = got_error_from_errno("asprintf");
5191 		goto done;
5192 	}
5193 	if (strcmp(path, "/") == 0) {
5194 		parent_path = strdup("");
5195 		if (parent_path == NULL)
5196 			return got_error_from_errno("strdup");
5197 	} else {
5198 		err = got_path_dirname(&parent_path, path);
5199 		if (err)
5200 			return err;
5201 	}
5202 
5203 	ct = calloc(1, sizeof(*ct));
5204 	if (ct == NULL) {
5205 		err = got_error_from_errno("calloc");
5206 		goto done;
5207 	}
5208 
5209 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
5210 	    relpath) == -1) {
5211 		err = got_error_from_errno("asprintf");
5212 		goto done;
5213 	}
5214 
5215 	if (staged_status == GOT_STATUS_ADD ||
5216 	    staged_status == GOT_STATUS_MODIFY) {
5217 		struct got_fileindex_entry *ie;
5218 		ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
5219 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
5220 		case GOT_FILEIDX_MODE_REGULAR_FILE:
5221 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
5222 			ct->mode = S_IFREG;
5223 			break;
5224 		case GOT_FILEIDX_MODE_SYMLINK:
5225 			ct->mode = S_IFLNK;
5226 			break;
5227 		default:
5228 			err = got_error_path(path, GOT_ERR_BAD_FILETYPE);
5229 			goto done;
5230 		}
5231 		ct->mode |= got_fileindex_entry_perms_get(ie);
5232 	} else if (status != GOT_STATUS_DELETE &&
5233 	    staged_status != GOT_STATUS_DELETE) {
5234 		if (dirfd != -1) {
5235 			if (fstatat(dirfd, de_name, &sb,
5236 			    AT_SYMLINK_NOFOLLOW) == -1) {
5237 				err = got_error_from_errno2("fstatat",
5238 				    ct->ondisk_path);
5239 				goto done;
5240 			}
5241 		} else if (lstat(ct->ondisk_path, &sb) == -1) {
5242 			err = got_error_from_errno2("lstat", ct->ondisk_path);
5243 			goto done;
5244 		}
5245 		ct->mode = sb.st_mode;
5246 	}
5247 
5248 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
5249 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
5250 	    relpath) == -1) {
5251 		err = got_error_from_errno("asprintf");
5252 		goto done;
5253 	}
5254 
5255 	if (S_ISLNK(ct->mode) && staged_status == GOT_STATUS_NO_CHANGE &&
5256 	    status == GOT_STATUS_ADD && !a->allow_bad_symlinks) {
5257 		int is_bad_symlink;
5258 		char target_path[PATH_MAX];
5259 		ssize_t target_len;
5260 		target_len = readlink(ct->ondisk_path, target_path,
5261 		    sizeof(target_path));
5262 		if (target_len == -1) {
5263 			err = got_error_from_errno2("readlink",
5264 			    ct->ondisk_path);
5265 			goto done;
5266 		}
5267 		err = is_bad_symlink_target(&is_bad_symlink, target_path,
5268 		    target_len, ct->ondisk_path, a->worktree->root_path);
5269 		if (err)
5270 			goto done;
5271 		if (is_bad_symlink) {
5272 			err = got_error_path(ct->ondisk_path,
5273 			    GOT_ERR_BAD_SYMLINK);
5274 			goto done;
5275 		}
5276 	}
5277 
5278 
5279 	ct->status = status;
5280 	ct->staged_status = staged_status;
5281 	ct->blob_id = NULL; /* will be filled in when blob gets created */
5282 	if (ct->status != GOT_STATUS_ADD &&
5283 	    ct->staged_status != GOT_STATUS_ADD) {
5284 		ct->base_blob_id = got_object_id_dup(blob_id);
5285 		if (ct->base_blob_id == NULL) {
5286 			err = got_error_from_errno("got_object_id_dup");
5287 			goto done;
5288 		}
5289 		ct->base_commit_id = got_object_id_dup(commit_id);
5290 		if (ct->base_commit_id == NULL) {
5291 			err = got_error_from_errno("got_object_id_dup");
5292 			goto done;
5293 		}
5294 	}
5295 	if (ct->staged_status == GOT_STATUS_ADD ||
5296 	    ct->staged_status == GOT_STATUS_MODIFY) {
5297 		ct->staged_blob_id = got_object_id_dup(staged_blob_id);
5298 		if (ct->staged_blob_id == NULL) {
5299 			err = got_error_from_errno("got_object_id_dup");
5300 			goto done;
5301 		}
5302 	}
5303 	ct->path = strdup(path);
5304 	if (ct->path == NULL) {
5305 		err = got_error_from_errno("strdup");
5306 		goto done;
5307 	}
5308 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
5309 	if (err)
5310 		goto done;
5311 
5312 	if (a->diff_outfile && ct && new != NULL) {
5313 		err = append_ct_diff(ct, &a->diff_header_shown,
5314 		    a->diff_outfile, a->f1, a->f2, dirfd, de_name,
5315 		    a->have_staged_files, a->repo, a->worktree);
5316 		if (err)
5317 			goto done;
5318 	}
5319 done:
5320 	if (ct && (err || new == NULL))
5321 		free_commitable(ct);
5322 	free(parent_path);
5323 	free(path);
5324 	return err;
5325 }
5326 
5327 static const struct got_error *write_tree(struct got_object_id **, int *,
5328     struct got_tree_object *, const char *, struct got_pathlist_head *,
5329     got_worktree_status_cb status_cb, void *status_arg,
5330     struct got_repository *);
5331 
5332 static const struct got_error *
5333 write_subtree(struct got_object_id **new_subtree_id, int *nentries,
5334     struct got_tree_entry *te, const char *parent_path,
5335     struct got_pathlist_head *commitable_paths,
5336     got_worktree_status_cb status_cb, void *status_arg,
5337     struct got_repository *repo)
5338 {
5339 	const struct got_error *err = NULL;
5340 	struct got_tree_object *subtree;
5341 	char *subpath;
5342 
5343 	if (asprintf(&subpath, "%s%s%s", parent_path,
5344 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
5345 		return got_error_from_errno("asprintf");
5346 
5347 	err = got_object_open_as_tree(&subtree, repo, &te->id);
5348 	if (err)
5349 		return err;
5350 
5351 	err = write_tree(new_subtree_id, nentries, subtree, subpath,
5352 	    commitable_paths, status_cb, status_arg, repo);
5353 	got_object_tree_close(subtree);
5354 	free(subpath);
5355 	return err;
5356 }
5357 
5358 static const struct got_error *
5359 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
5360 {
5361 	const struct got_error *err = NULL;
5362 	char *ct_parent_path = NULL;
5363 
5364 	*match = 0;
5365 
5366 	if (strchr(ct->in_repo_path, '/') == NULL) {
5367 		*match = got_path_is_root_dir(path);
5368 		return NULL;
5369 	}
5370 
5371 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
5372 	if (err)
5373 		return err;
5374 	*match = (strcmp(path, ct_parent_path) == 0);
5375 	free(ct_parent_path);
5376 	return err;
5377 }
5378 
5379 static mode_t
5380 get_ct_file_mode(struct got_commitable *ct)
5381 {
5382 	if (S_ISLNK(ct->mode))
5383 		return S_IFLNK;
5384 
5385 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
5386 }
5387 
5388 static const struct got_error *
5389 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
5390     struct got_tree_entry *te, struct got_commitable *ct)
5391 {
5392 	const struct got_error *err = NULL;
5393 
5394 	*new_te = NULL;
5395 
5396 	err = got_object_tree_entry_dup(new_te, te);
5397 	if (err)
5398 		goto done;
5399 
5400 	(*new_te)->mode = get_ct_file_mode(ct);
5401 
5402 	if (ct->staged_status == GOT_STATUS_MODIFY)
5403 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5404 		    sizeof((*new_te)->id));
5405 	else
5406 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5407 done:
5408 	if (err && *new_te) {
5409 		free(*new_te);
5410 		*new_te = NULL;
5411 	}
5412 	return err;
5413 }
5414 
5415 static const struct got_error *
5416 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
5417     struct got_commitable *ct)
5418 {
5419 	const struct got_error *err = NULL;
5420 	char *ct_name = NULL;
5421 
5422 	 *new_te = NULL;
5423 
5424 	*new_te = calloc(1, sizeof(**new_te));
5425 	if (*new_te == NULL)
5426 		return got_error_from_errno("calloc");
5427 
5428 	err = got_path_basename(&ct_name, ct->path);
5429 	if (err)
5430 		goto done;
5431 	if (strlcpy((*new_te)->name, ct_name, sizeof((*new_te)->name)) >=
5432 	    sizeof((*new_te)->name)) {
5433 		err = got_error(GOT_ERR_NO_SPACE);
5434 		goto done;
5435 	}
5436 
5437 	(*new_te)->mode = get_ct_file_mode(ct);
5438 
5439 	if (ct->staged_status == GOT_STATUS_ADD)
5440 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5441 		    sizeof((*new_te)->id));
5442 	else
5443 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5444 done:
5445 	free(ct_name);
5446 	if (err && *new_te) {
5447 		free(*new_te);
5448 		*new_te = NULL;
5449 	}
5450 	return err;
5451 }
5452 
5453 static const struct got_error *
5454 insert_tree_entry(struct got_tree_entry *new_te,
5455     struct got_pathlist_head *paths)
5456 {
5457 	const struct got_error *err = NULL;
5458 	struct got_pathlist_entry *new_pe;
5459 
5460 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
5461 	if (err)
5462 		return err;
5463 	if (new_pe == NULL)
5464 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
5465 	return NULL;
5466 }
5467 
5468 static const struct got_error *
5469 report_ct_status(struct got_commitable *ct,
5470     got_worktree_status_cb status_cb, void *status_arg)
5471 {
5472 	const char *ct_path = ct->path;
5473 	unsigned char status;
5474 
5475 	if (status_cb == NULL) /* no commit progress output desired */
5476 		return NULL;
5477 
5478 	while (ct_path[0] == '/')
5479 		ct_path++;
5480 
5481 	if (ct->staged_status != GOT_STATUS_NO_CHANGE)
5482 		status = ct->staged_status;
5483 	else
5484 		status = ct->status;
5485 
5486 	return (*status_cb)(status_arg, status, GOT_STATUS_NO_CHANGE,
5487 	    ct_path, ct->blob_id, NULL, NULL, -1, NULL);
5488 }
5489 
5490 static const struct got_error *
5491 match_modified_subtree(int *modified, struct got_tree_entry *te,
5492     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
5493 {
5494 	const struct got_error *err = NULL;
5495 	struct got_pathlist_entry *pe;
5496 	char *te_path;
5497 
5498 	*modified = 0;
5499 
5500 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
5501 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
5502 	    te->name) == -1)
5503 		return got_error_from_errno("asprintf");
5504 
5505 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5506 		struct got_commitable *ct = pe->data;
5507 		*modified = got_path_is_child(ct->in_repo_path, te_path,
5508 		    strlen(te_path));
5509 		if (*modified)
5510 			break;
5511 	}
5512 
5513 	free(te_path);
5514 	return err;
5515 }
5516 
5517 static const struct got_error *
5518 match_deleted_or_modified_ct(struct got_commitable **ctp,
5519     struct got_tree_entry *te, const char *base_tree_path,
5520     struct got_pathlist_head *commitable_paths)
5521 {
5522 	const struct got_error *err = NULL;
5523 	struct got_pathlist_entry *pe;
5524 
5525 	*ctp = NULL;
5526 
5527 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5528 		struct got_commitable *ct = pe->data;
5529 		char *ct_name = NULL;
5530 		int path_matches;
5531 
5532 		if (ct->staged_status == GOT_STATUS_NO_CHANGE) {
5533 			if (ct->status != GOT_STATUS_MODIFY &&
5534 			    ct->status != GOT_STATUS_MODE_CHANGE &&
5535 			    ct->status != GOT_STATUS_DELETE)
5536 				continue;
5537 		} else {
5538 			if (ct->staged_status != GOT_STATUS_MODIFY &&
5539 			    ct->staged_status != GOT_STATUS_DELETE)
5540 				continue;
5541 		}
5542 
5543 		if (got_object_id_cmp(ct->base_blob_id, &te->id) != 0)
5544 			continue;
5545 
5546 		err = match_ct_parent_path(&path_matches, ct, base_tree_path);
5547 		if (err)
5548 			return err;
5549 		if (!path_matches)
5550 			continue;
5551 
5552 		err = got_path_basename(&ct_name, pe->path);
5553 		if (err)
5554 			return err;
5555 
5556 		if (strcmp(te->name, ct_name) != 0) {
5557 			free(ct_name);
5558 			continue;
5559 		}
5560 		free(ct_name);
5561 
5562 		*ctp = ct;
5563 		break;
5564 	}
5565 
5566 	return err;
5567 }
5568 
5569 static const struct got_error *
5570 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
5571     const char *child_path, const char *path_base_tree,
5572     struct got_pathlist_head *commitable_paths,
5573     got_worktree_status_cb status_cb, void *status_arg,
5574     struct got_repository *repo)
5575 {
5576 	const struct got_error *err = NULL;
5577 	struct got_tree_entry *new_te;
5578 	char *subtree_path;
5579 	struct got_object_id *id = NULL;
5580 	int nentries;
5581 
5582 	*new_tep = NULL;
5583 
5584 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
5585 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
5586 	    child_path) == -1)
5587 		return got_error_from_errno("asprintf");
5588 
5589 	new_te = calloc(1, sizeof(*new_te));
5590 	if (new_te == NULL)
5591 		return got_error_from_errno("calloc");
5592 	new_te->mode = S_IFDIR;
5593 
5594 	if (strlcpy(new_te->name, child_path, sizeof(new_te->name)) >=
5595 	    sizeof(new_te->name)) {
5596 		err = got_error(GOT_ERR_NO_SPACE);
5597 		goto done;
5598 	}
5599 	err = write_tree(&id, &nentries, NULL, subtree_path,
5600 	    commitable_paths, status_cb, status_arg, repo);
5601 	if (err) {
5602 		free(new_te);
5603 		goto done;
5604 	}
5605 	memcpy(&new_te->id, id, sizeof(new_te->id));
5606 done:
5607 	free(id);
5608 	free(subtree_path);
5609 	if (err == NULL)
5610 		*new_tep = new_te;
5611 	return err;
5612 }
5613 
5614 static const struct got_error *
5615 write_tree(struct got_object_id **new_tree_id, int *nentries,
5616     struct got_tree_object *base_tree, const char *path_base_tree,
5617     struct got_pathlist_head *commitable_paths,
5618     got_worktree_status_cb status_cb, void *status_arg,
5619     struct got_repository *repo)
5620 {
5621 	const struct got_error *err = NULL;
5622 	struct got_pathlist_head paths;
5623 	struct got_tree_entry *te, *new_te = NULL;
5624 	struct got_pathlist_entry *pe;
5625 
5626 	TAILQ_INIT(&paths);
5627 	*nentries = 0;
5628 
5629 	/* Insert, and recurse into, newly added entries first. */
5630 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5631 		struct got_commitable *ct = pe->data;
5632 		char *child_path = NULL, *slash;
5633 
5634 		if ((ct->status != GOT_STATUS_ADD &&
5635 		    ct->staged_status != GOT_STATUS_ADD) ||
5636 		    (ct->flags & GOT_COMMITABLE_ADDED))
5637 			continue;
5638 
5639 		if (!got_path_is_child(ct->in_repo_path, path_base_tree,
5640 		    strlen(path_base_tree)))
5641 			continue;
5642 
5643 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
5644 		    ct->in_repo_path);
5645 		if (err)
5646 			goto done;
5647 
5648 		slash = strchr(child_path, '/');
5649 		if (slash == NULL) {
5650 			err = alloc_added_blob_tree_entry(&new_te, ct);
5651 			if (err)
5652 				goto done;
5653 			err = report_ct_status(ct, status_cb, status_arg);
5654 			if (err)
5655 				goto done;
5656 			ct->flags |= GOT_COMMITABLE_ADDED;
5657 			err = insert_tree_entry(new_te, &paths);
5658 			if (err)
5659 				goto done;
5660 			(*nentries)++;
5661 		} else {
5662 			*slash = '\0'; /* trim trailing path components */
5663 			if (base_tree == NULL ||
5664 			    got_object_tree_find_entry(base_tree, child_path)
5665 			    == NULL) {
5666 				err = make_subtree_for_added_blob(&new_te,
5667 				    child_path, path_base_tree,
5668 				    commitable_paths, status_cb, status_arg,
5669 				    repo);
5670 				if (err)
5671 					goto done;
5672 				err = insert_tree_entry(new_te, &paths);
5673 				if (err)
5674 					goto done;
5675 				(*nentries)++;
5676 			}
5677 		}
5678 	}
5679 
5680 	if (base_tree) {
5681 		int i, nbase_entries;
5682 		/* Handle modified and deleted entries. */
5683 		nbase_entries = got_object_tree_get_nentries(base_tree);
5684 		for (i = 0; i < nbase_entries; i++) {
5685 			struct got_commitable *ct = NULL;
5686 
5687 			te = got_object_tree_get_entry(base_tree, i);
5688 			if (got_object_tree_entry_is_submodule(te)) {
5689 				/* Entry is a submodule; just copy it. */
5690 				err = got_object_tree_entry_dup(&new_te, te);
5691 				if (err)
5692 					goto done;
5693 				err = insert_tree_entry(new_te, &paths);
5694 				if (err)
5695 					goto done;
5696 				(*nentries)++;
5697 				continue;
5698 			}
5699 
5700 			if (S_ISDIR(te->mode)) {
5701 				int modified;
5702 				err = got_object_tree_entry_dup(&new_te, te);
5703 				if (err)
5704 					goto done;
5705 				err = match_modified_subtree(&modified, te,
5706 				    path_base_tree, commitable_paths);
5707 				if (err)
5708 					goto done;
5709 				/* Avoid recursion into unmodified subtrees. */
5710 				if (modified) {
5711 					struct got_object_id *new_id;
5712 					int nsubentries;
5713 					err = write_subtree(&new_id,
5714 					    &nsubentries, te,
5715 					    path_base_tree, commitable_paths,
5716 					    status_cb, status_arg, repo);
5717 					if (err)
5718 						goto done;
5719 					if (nsubentries == 0) {
5720 						/* All entries were deleted. */
5721 						free(new_id);
5722 						continue;
5723 					}
5724 					memcpy(&new_te->id, new_id,
5725 					    sizeof(new_te->id));
5726 					free(new_id);
5727 				}
5728 				err = insert_tree_entry(new_te, &paths);
5729 				if (err)
5730 					goto done;
5731 				(*nentries)++;
5732 				continue;
5733 			}
5734 
5735 			err = match_deleted_or_modified_ct(&ct, te,
5736 			    path_base_tree, commitable_paths);
5737 			if (err)
5738 				goto done;
5739 			if (ct) {
5740 				/* NB: Deleted entries get dropped here. */
5741 				if (ct->status == GOT_STATUS_MODIFY ||
5742 				    ct->status == GOT_STATUS_MODE_CHANGE ||
5743 				    ct->staged_status == GOT_STATUS_MODIFY) {
5744 					err = alloc_modified_blob_tree_entry(
5745 					    &new_te, te, ct);
5746 					if (err)
5747 						goto done;
5748 					err = insert_tree_entry(new_te, &paths);
5749 					if (err)
5750 						goto done;
5751 					(*nentries)++;
5752 				}
5753 				err = report_ct_status(ct, status_cb,
5754 				    status_arg);
5755 				if (err)
5756 					goto done;
5757 			} else {
5758 				/* Entry is unchanged; just copy it. */
5759 				err = got_object_tree_entry_dup(&new_te, te);
5760 				if (err)
5761 					goto done;
5762 				err = insert_tree_entry(new_te, &paths);
5763 				if (err)
5764 					goto done;
5765 				(*nentries)++;
5766 			}
5767 		}
5768 	}
5769 
5770 	/* Write new list of entries; deleted entries have been dropped. */
5771 	err = got_object_tree_create(new_tree_id, &paths, *nentries, repo);
5772 done:
5773 	got_pathlist_free(&paths, GOT_PATHLIST_FREE_NONE);
5774 	return err;
5775 }
5776 
5777 static const struct got_error *
5778 update_fileindex_after_commit(struct got_worktree *worktree,
5779     struct got_pathlist_head *commitable_paths,
5780     struct got_object_id *new_base_commit_id,
5781     struct got_fileindex *fileindex, int have_staged_files)
5782 {
5783 	const struct got_error *err = NULL;
5784 	struct got_pathlist_entry *pe;
5785 	char *relpath = NULL;
5786 
5787 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5788 		struct got_fileindex_entry *ie;
5789 		struct got_commitable *ct = pe->data;
5790 
5791 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
5792 
5793 		err = got_path_skip_common_ancestor(&relpath,
5794 		    worktree->root_path, ct->ondisk_path);
5795 		if (err)
5796 			goto done;
5797 
5798 		if (ie) {
5799 			if (ct->status == GOT_STATUS_DELETE ||
5800 			    ct->staged_status == GOT_STATUS_DELETE) {
5801 				got_fileindex_entry_remove(fileindex, ie);
5802 			} else if (ct->staged_status == GOT_STATUS_ADD ||
5803 			    ct->staged_status == GOT_STATUS_MODIFY) {
5804 				got_fileindex_entry_stage_set(ie,
5805 				    GOT_FILEIDX_STAGE_NONE);
5806 				got_fileindex_entry_staged_filetype_set(ie, 0);
5807 
5808 				err = got_fileindex_entry_update(ie,
5809 				    worktree->root_fd, relpath,
5810 				    ct->staged_blob_id->sha1,
5811 				    new_base_commit_id->sha1,
5812 				    !have_staged_files);
5813 			} else
5814 				err = got_fileindex_entry_update(ie,
5815 				    worktree->root_fd, relpath,
5816 				    ct->blob_id->sha1,
5817 				    new_base_commit_id->sha1,
5818 				    !have_staged_files);
5819 		} else {
5820 			err = got_fileindex_entry_alloc(&ie, pe->path);
5821 			if (err)
5822 				goto done;
5823 			err = got_fileindex_entry_update(ie,
5824 			    worktree->root_fd, relpath, ct->blob_id->sha1,
5825 			    new_base_commit_id->sha1, 1);
5826 			if (err) {
5827 				got_fileindex_entry_free(ie);
5828 				goto done;
5829 			}
5830 			err = got_fileindex_entry_add(fileindex, ie);
5831 			if (err) {
5832 				got_fileindex_entry_free(ie);
5833 				goto done;
5834 			}
5835 		}
5836 		free(relpath);
5837 		relpath = NULL;
5838 	}
5839 done:
5840 	free(relpath);
5841 	return err;
5842 }
5843 
5844 
5845 static const struct got_error *
5846 check_out_of_date(const char *in_repo_path, unsigned char status,
5847     unsigned char staged_status, struct got_object_id *base_blob_id,
5848     struct got_object_id *base_commit_id,
5849     struct got_object_id *head_commit_id, struct got_repository *repo,
5850     int ood_errcode)
5851 {
5852 	const struct got_error *err = NULL;
5853 	struct got_commit_object *commit = NULL;
5854 	struct got_object_id *id = NULL;
5855 
5856 	if (status != GOT_STATUS_ADD && staged_status != GOT_STATUS_ADD) {
5857 		/* Trivial case: base commit == head commit */
5858 		if (got_object_id_cmp(base_commit_id, head_commit_id) == 0)
5859 			return NULL;
5860 		/*
5861 		 * Ensure file content which local changes were based
5862 		 * on matches file content in the branch head.
5863 		 */
5864 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
5865 		if (err)
5866 			goto done;
5867 		err = got_object_id_by_path(&id, repo, commit, in_repo_path);
5868 		if (err) {
5869 			if (err->code == GOT_ERR_NO_TREE_ENTRY)
5870 				err = got_error(ood_errcode);
5871 			goto done;
5872 		} else if (got_object_id_cmp(id, base_blob_id) != 0)
5873 			err = got_error(ood_errcode);
5874 	} else {
5875 		/* Require that added files don't exist in the branch head. */
5876 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
5877 		if (err)
5878 			goto done;
5879 		err = got_object_id_by_path(&id, repo, commit, in_repo_path);
5880 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
5881 			goto done;
5882 		err = id ? got_error(ood_errcode) : NULL;
5883 	}
5884 done:
5885 	free(id);
5886 	if (commit)
5887 		got_object_commit_close(commit);
5888 	return err;
5889 }
5890 
5891 static const struct got_error *
5892 commit_worktree(struct got_object_id **new_commit_id,
5893     struct got_pathlist_head *commitable_paths,
5894     struct got_object_id *head_commit_id,
5895     struct got_object_id *parent_id2,
5896     struct got_worktree *worktree,
5897     const char *author, const char *committer, char *diff_path,
5898     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
5899     got_worktree_status_cb status_cb, void *status_arg,
5900     struct got_repository *repo)
5901 {
5902 	const struct got_error *err = NULL, *unlockerr = NULL;
5903 	struct got_pathlist_entry *pe;
5904 	const char *head_ref_name = NULL;
5905 	struct got_commit_object *head_commit = NULL;
5906 	struct got_reference *head_ref2 = NULL;
5907 	struct got_object_id *head_commit_id2 = NULL;
5908 	struct got_tree_object *head_tree = NULL;
5909 	struct got_object_id *new_tree_id = NULL;
5910 	int nentries, nparents = 0;
5911 	struct got_object_id_queue parent_ids;
5912 	struct got_object_qid *pid = NULL;
5913 	char *logmsg = NULL;
5914 	time_t timestamp;
5915 
5916 	*new_commit_id = NULL;
5917 
5918 	STAILQ_INIT(&parent_ids);
5919 
5920 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
5921 	if (err)
5922 		goto done;
5923 
5924 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
5925 	if (err)
5926 		goto done;
5927 
5928 	if (commit_msg_cb != NULL) {
5929 		err = commit_msg_cb(commitable_paths, diff_path,
5930 		    &logmsg, commit_arg);
5931 		if (err)
5932 			goto done;
5933 	}
5934 
5935 	if (logmsg == NULL || strlen(logmsg) == 0) {
5936 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
5937 		goto done;
5938 	}
5939 
5940 	/* Create blobs from added and modified files and record their IDs. */
5941 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5942 		struct got_commitable *ct = pe->data;
5943 		char *ondisk_path;
5944 
5945 		/* Blobs for staged files already exist. */
5946 		if (ct->staged_status == GOT_STATUS_ADD ||
5947 		    ct->staged_status == GOT_STATUS_MODIFY)
5948 			continue;
5949 
5950 		if (ct->status != GOT_STATUS_ADD &&
5951 		    ct->status != GOT_STATUS_MODIFY &&
5952 		    ct->status != GOT_STATUS_MODE_CHANGE)
5953 			continue;
5954 
5955 		if (asprintf(&ondisk_path, "%s/%s",
5956 		    worktree->root_path, pe->path) == -1) {
5957 			err = got_error_from_errno("asprintf");
5958 			goto done;
5959 		}
5960 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
5961 		free(ondisk_path);
5962 		if (err)
5963 			goto done;
5964 	}
5965 
5966 	/* Recursively write new tree objects. */
5967 	err = write_tree(&new_tree_id, &nentries, head_tree, "/",
5968 	    commitable_paths, status_cb, status_arg, repo);
5969 	if (err)
5970 		goto done;
5971 
5972 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
5973 	if (err)
5974 		goto done;
5975 	STAILQ_INSERT_TAIL(&parent_ids, pid, entry);
5976 	nparents++;
5977 	if (parent_id2) {
5978 		err = got_object_qid_alloc(&pid, parent_id2);
5979 		if (err)
5980 			goto done;
5981 		STAILQ_INSERT_TAIL(&parent_ids, pid, entry);
5982 		nparents++;
5983 	}
5984 	timestamp = time(NULL);
5985 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
5986 	    nparents, author, timestamp, committer, timestamp, logmsg, repo);
5987 	if (logmsg != NULL)
5988 		free(logmsg);
5989 	if (err)
5990 		goto done;
5991 
5992 	/* Check if a concurrent commit to our branch has occurred. */
5993 	head_ref_name = got_worktree_get_head_ref_name(worktree);
5994 	if (head_ref_name == NULL) {
5995 		err = got_error_from_errno("got_worktree_get_head_ref_name");
5996 		goto done;
5997 	}
5998 	/* Lock the reference here to prevent concurrent modification. */
5999 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
6000 	if (err)
6001 		goto done;
6002 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
6003 	if (err)
6004 		goto done;
6005 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
6006 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
6007 		goto done;
6008 	}
6009 	/* Update branch head in repository. */
6010 	err = got_ref_change_ref(head_ref2, *new_commit_id);
6011 	if (err)
6012 		goto done;
6013 	err = got_ref_write(head_ref2, repo);
6014 	if (err)
6015 		goto done;
6016 
6017 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
6018 	if (err)
6019 		goto done;
6020 
6021 	err = ref_base_commit(worktree, repo);
6022 	if (err)
6023 		goto done;
6024 done:
6025 	got_object_id_queue_free(&parent_ids);
6026 	if (head_tree)
6027 		got_object_tree_close(head_tree);
6028 	if (head_commit)
6029 		got_object_commit_close(head_commit);
6030 	free(head_commit_id2);
6031 	if (head_ref2) {
6032 		unlockerr = got_ref_unlock(head_ref2);
6033 		if (unlockerr && err == NULL)
6034 			err = unlockerr;
6035 		got_ref_close(head_ref2);
6036 	}
6037 	return err;
6038 }
6039 
6040 static const struct got_error *
6041 check_path_is_commitable(const char *path,
6042     struct got_pathlist_head *commitable_paths)
6043 {
6044 	struct got_pathlist_entry *cpe = NULL;
6045 	size_t path_len = strlen(path);
6046 
6047 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
6048 		struct got_commitable *ct = cpe->data;
6049 		const char *ct_path = ct->path;
6050 
6051 		while (ct_path[0] == '/')
6052 			ct_path++;
6053 
6054 		if (strcmp(path, ct_path) == 0 ||
6055 		    got_path_is_child(ct_path, path, path_len))
6056 			break;
6057 	}
6058 
6059 	if (cpe == NULL)
6060 		return got_error_path(path, GOT_ERR_BAD_PATH);
6061 
6062 	return NULL;
6063 }
6064 
6065 static const struct got_error *
6066 check_staged_file(void *arg, struct got_fileindex_entry *ie)
6067 {
6068 	int *have_staged_files = arg;
6069 
6070 	if (got_fileindex_entry_stage_get(ie) != GOT_FILEIDX_STAGE_NONE) {
6071 		*have_staged_files = 1;
6072 		return got_error(GOT_ERR_CANCELLED);
6073 	}
6074 
6075 	return NULL;
6076 }
6077 
6078 static const struct got_error *
6079 check_non_staged_files(struct got_fileindex *fileindex,
6080     struct got_pathlist_head *paths)
6081 {
6082 	struct got_pathlist_entry *pe;
6083 	struct got_fileindex_entry *ie;
6084 
6085 	TAILQ_FOREACH(pe, paths, entry) {
6086 		if (pe->path[0] == '\0')
6087 			continue;
6088 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
6089 		if (ie == NULL)
6090 			return got_error_path(pe->path, GOT_ERR_BAD_PATH);
6091 		if (got_fileindex_entry_stage_get(ie) == GOT_FILEIDX_STAGE_NONE)
6092 			return got_error_path(pe->path,
6093 			    GOT_ERR_FILE_NOT_STAGED);
6094 	}
6095 
6096 	return NULL;
6097 }
6098 
6099 const struct got_error *
6100 got_worktree_commit(struct got_object_id **new_commit_id,
6101     struct got_worktree *worktree, struct got_pathlist_head *paths,
6102     const char *author, const char *committer, int allow_bad_symlinks,
6103     int show_diff, got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
6104     got_worktree_status_cb status_cb, void *status_arg,
6105     struct got_repository *repo)
6106 {
6107 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
6108 	struct got_fileindex *fileindex = NULL;
6109 	char *fileindex_path = NULL;
6110 	struct got_pathlist_head commitable_paths;
6111 	struct collect_commitables_arg cc_arg;
6112 	struct got_pathlist_entry *pe;
6113 	struct got_reference *head_ref = NULL;
6114 	struct got_object_id *head_commit_id = NULL;
6115 	char *diff_path = NULL;
6116 	int have_staged_files = 0;
6117 
6118 	*new_commit_id = NULL;
6119 
6120 	memset(&cc_arg, 0, sizeof(cc_arg));
6121 	TAILQ_INIT(&commitable_paths);
6122 
6123 	err = lock_worktree(worktree, LOCK_EX);
6124 	if (err)
6125 		goto done;
6126 
6127 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6128 	if (err)
6129 		goto done;
6130 
6131 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6132 	if (err)
6133 		goto done;
6134 
6135 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
6136 	if (err)
6137 		goto done;
6138 
6139 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
6140 	    &have_staged_files);
6141 	if (err && err->code != GOT_ERR_CANCELLED)
6142 		goto done;
6143 	if (have_staged_files) {
6144 		err = check_non_staged_files(fileindex, paths);
6145 		if (err)
6146 			goto done;
6147 	}
6148 
6149 	cc_arg.commitable_paths = &commitable_paths;
6150 	cc_arg.worktree = worktree;
6151 	cc_arg.fileindex = fileindex;
6152 	cc_arg.repo = repo;
6153 	cc_arg.have_staged_files = have_staged_files;
6154 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
6155 	cc_arg.diff_header_shown = 0;
6156 	if (show_diff) {
6157 		err = got_opentemp_named(&diff_path, &cc_arg.diff_outfile,
6158 		    GOT_TMPDIR_STR "/got", ".diff");
6159 		if (err)
6160 			goto done;
6161 		cc_arg.f1 = got_opentemp();
6162 		if (cc_arg.f1 == NULL) {
6163 			err = got_error_from_errno("got_opentemp");
6164 			goto done;
6165 		}
6166 		cc_arg.f2 = got_opentemp();
6167 		if (cc_arg.f2 == NULL) {
6168 			err = got_error_from_errno("got_opentemp");
6169 			goto done;
6170 		}
6171 	}
6172 
6173 	TAILQ_FOREACH(pe, paths, entry) {
6174 		err = worktree_status(worktree, pe->path, fileindex, repo,
6175 		    collect_commitables, &cc_arg, NULL, NULL, 0, 0);
6176 		if (err)
6177 			goto done;
6178 	}
6179 
6180 	if (show_diff) {
6181 		if (fflush(cc_arg.diff_outfile) == EOF) {
6182 			err = got_error_from_errno("fflush");
6183 			goto done;
6184 		}
6185 	}
6186 
6187 	if (TAILQ_EMPTY(&commitable_paths)) {
6188 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6189 		goto done;
6190 	}
6191 
6192 	TAILQ_FOREACH(pe, paths, entry) {
6193 		err = check_path_is_commitable(pe->path, &commitable_paths);
6194 		if (err)
6195 			goto done;
6196 	}
6197 
6198 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
6199 		struct got_commitable *ct = pe->data;
6200 		const char *ct_path = ct->in_repo_path;
6201 
6202 		while (ct_path[0] == '/')
6203 			ct_path++;
6204 		err = check_out_of_date(ct_path, ct->status,
6205 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
6206 		    head_commit_id, repo, GOT_ERR_COMMIT_OUT_OF_DATE);
6207 		if (err)
6208 			goto done;
6209 
6210 	}
6211 
6212 	err = commit_worktree(new_commit_id, &commitable_paths,
6213 	    head_commit_id, NULL, worktree, author, committer,
6214 	    (diff_path && cc_arg.diff_header_shown) ? diff_path : NULL,
6215 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
6216 	if (err)
6217 		goto done;
6218 
6219 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6220 	    *new_commit_id, fileindex, have_staged_files);
6221 	sync_err = sync_fileindex(fileindex, fileindex_path);
6222 	if (sync_err && err == NULL)
6223 		err = sync_err;
6224 done:
6225 	if (fileindex)
6226 		got_fileindex_free(fileindex);
6227 	free(fileindex_path);
6228 	unlockerr = lock_worktree(worktree, LOCK_SH);
6229 	if (unlockerr && err == NULL)
6230 		err = unlockerr;
6231 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
6232 		struct got_commitable *ct = pe->data;
6233 
6234 		free_commitable(ct);
6235 	}
6236 	got_pathlist_free(&commitable_paths, GOT_PATHLIST_FREE_NONE);
6237 	if (diff_path && unlink(diff_path) == -1 && err == NULL)
6238 		err = got_error_from_errno2("unlink", diff_path);
6239 	free(diff_path);
6240 	if (cc_arg.diff_outfile && fclose(cc_arg.diff_outfile) == EOF &&
6241 	    err == NULL)
6242 		err = got_error_from_errno("fclose");
6243 	return err;
6244 }
6245 
6246 const char *
6247 got_commitable_get_path(struct got_commitable *ct)
6248 {
6249 	return ct->path;
6250 }
6251 
6252 unsigned int
6253 got_commitable_get_status(struct got_commitable *ct)
6254 {
6255 	return ct->status;
6256 }
6257 
6258 struct check_rebase_ok_arg {
6259 	struct got_worktree *worktree;
6260 	struct got_repository *repo;
6261 };
6262 
6263 static const struct got_error *
6264 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
6265 {
6266 	const struct got_error *err = NULL;
6267 	struct check_rebase_ok_arg *a = arg;
6268 	unsigned char status;
6269 	struct stat sb;
6270 	char *ondisk_path;
6271 
6272 	/* Reject rebase of a work tree with mixed base commits. */
6273 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
6274 	    SHA1_DIGEST_LENGTH))
6275 		return got_error(GOT_ERR_MIXED_COMMITS);
6276 
6277 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
6278 	    == -1)
6279 		return got_error_from_errno("asprintf");
6280 
6281 	/* Reject rebase of a work tree with modified or staged files. */
6282 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
6283 	free(ondisk_path);
6284 	if (err)
6285 		return err;
6286 
6287 	if (status != GOT_STATUS_NO_CHANGE)
6288 		return got_error(GOT_ERR_MODIFIED);
6289 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
6290 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
6291 
6292 	return NULL;
6293 }
6294 
6295 const struct got_error *
6296 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
6297     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
6298     struct got_worktree *worktree, struct got_reference *branch,
6299     struct got_repository *repo)
6300 {
6301 	const struct got_error *err = NULL;
6302 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
6303 	char *branch_ref_name = NULL;
6304 	char *fileindex_path = NULL;
6305 	struct check_rebase_ok_arg ok_arg;
6306 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
6307 	struct got_object_id *wt_branch_tip = NULL;
6308 
6309 	*new_base_branch_ref = NULL;
6310 	*tmp_branch = NULL;
6311 	*fileindex = NULL;
6312 
6313 	err = lock_worktree(worktree, LOCK_EX);
6314 	if (err)
6315 		return err;
6316 
6317 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6318 	if (err)
6319 		goto done;
6320 
6321 	ok_arg.worktree = worktree;
6322 	ok_arg.repo = repo;
6323 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
6324 	    &ok_arg);
6325 	if (err)
6326 		goto done;
6327 
6328 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6329 	if (err)
6330 		goto done;
6331 
6332 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6333 	if (err)
6334 		goto done;
6335 
6336 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6337 	if (err)
6338 		goto done;
6339 
6340 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
6341 	    0);
6342 	if (err)
6343 		goto done;
6344 
6345 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
6346 	if (err)
6347 		goto done;
6348 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
6349 		err = got_error(GOT_ERR_REBASE_OUT_OF_DATE);
6350 		goto done;
6351 	}
6352 
6353 	err = got_ref_alloc_symref(new_base_branch_ref,
6354 	    new_base_branch_ref_name, wt_branch);
6355 	if (err)
6356 		goto done;
6357 	err = got_ref_write(*new_base_branch_ref, repo);
6358 	if (err)
6359 		goto done;
6360 
6361 	/* TODO Lock original branch's ref while rebasing? */
6362 
6363 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
6364 	if (err)
6365 		goto done;
6366 
6367 	err = got_ref_write(branch_ref, repo);
6368 	if (err)
6369 		goto done;
6370 
6371 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
6372 	    worktree->base_commit_id);
6373 	if (err)
6374 		goto done;
6375 	err = got_ref_write(*tmp_branch, repo);
6376 	if (err)
6377 		goto done;
6378 
6379 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
6380 	if (err)
6381 		goto done;
6382 done:
6383 	free(fileindex_path);
6384 	free(tmp_branch_name);
6385 	free(new_base_branch_ref_name);
6386 	free(branch_ref_name);
6387 	if (branch_ref)
6388 		got_ref_close(branch_ref);
6389 	if (wt_branch)
6390 		got_ref_close(wt_branch);
6391 	free(wt_branch_tip);
6392 	if (err) {
6393 		if (*new_base_branch_ref) {
6394 			got_ref_close(*new_base_branch_ref);
6395 			*new_base_branch_ref = NULL;
6396 		}
6397 		if (*tmp_branch) {
6398 			got_ref_close(*tmp_branch);
6399 			*tmp_branch = NULL;
6400 		}
6401 		if (*fileindex) {
6402 			got_fileindex_free(*fileindex);
6403 			*fileindex = NULL;
6404 		}
6405 		lock_worktree(worktree, LOCK_SH);
6406 	}
6407 	return err;
6408 }
6409 
6410 const struct got_error *
6411 got_worktree_rebase_continue(struct got_object_id **commit_id,
6412     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
6413     struct got_reference **branch, struct got_fileindex **fileindex,
6414     struct got_worktree *worktree, struct got_repository *repo)
6415 {
6416 	const struct got_error *err;
6417 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
6418 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
6419 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
6420 	char *fileindex_path = NULL;
6421 	int have_staged_files = 0;
6422 
6423 	*commit_id = NULL;
6424 	*new_base_branch = NULL;
6425 	*tmp_branch = NULL;
6426 	*branch = NULL;
6427 	*fileindex = NULL;
6428 
6429 	err = lock_worktree(worktree, LOCK_EX);
6430 	if (err)
6431 		return err;
6432 
6433 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6434 	if (err)
6435 		goto done;
6436 
6437 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
6438 	    &have_staged_files);
6439 	if (err && err->code != GOT_ERR_CANCELLED)
6440 		goto done;
6441 	if (have_staged_files) {
6442 		err = got_error(GOT_ERR_STAGED_PATHS);
6443 		goto done;
6444 	}
6445 
6446 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6447 	if (err)
6448 		goto done;
6449 
6450 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6451 	if (err)
6452 		goto done;
6453 
6454 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6455 	if (err)
6456 		goto done;
6457 
6458 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6459 	if (err)
6460 		goto done;
6461 
6462 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
6463 	if (err)
6464 		goto done;
6465 
6466 	err = got_ref_open(branch, repo,
6467 	    got_ref_get_symref_target(branch_ref), 0);
6468 	if (err)
6469 		goto done;
6470 
6471 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6472 	if (err)
6473 		goto done;
6474 
6475 	err = got_ref_resolve(commit_id, repo, commit_ref);
6476 	if (err)
6477 		goto done;
6478 
6479 	err = got_ref_open(new_base_branch, repo,
6480 	    new_base_branch_ref_name, 0);
6481 	if (err)
6482 		goto done;
6483 
6484 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
6485 	if (err)
6486 		goto done;
6487 done:
6488 	free(commit_ref_name);
6489 	free(branch_ref_name);
6490 	free(fileindex_path);
6491 	if (commit_ref)
6492 		got_ref_close(commit_ref);
6493 	if (branch_ref)
6494 		got_ref_close(branch_ref);
6495 	if (err) {
6496 		free(*commit_id);
6497 		*commit_id = NULL;
6498 		if (*tmp_branch) {
6499 			got_ref_close(*tmp_branch);
6500 			*tmp_branch = NULL;
6501 		}
6502 		if (*new_base_branch) {
6503 			got_ref_close(*new_base_branch);
6504 			*new_base_branch = NULL;
6505 		}
6506 		if (*branch) {
6507 			got_ref_close(*branch);
6508 			*branch = NULL;
6509 		}
6510 		if (*fileindex) {
6511 			got_fileindex_free(*fileindex);
6512 			*fileindex = NULL;
6513 		}
6514 		lock_worktree(worktree, LOCK_SH);
6515 	}
6516 	return err;
6517 }
6518 
6519 const struct got_error *
6520 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
6521 {
6522 	const struct got_error *err;
6523 	char *tmp_branch_name = NULL;
6524 
6525 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6526 	if (err)
6527 		return err;
6528 
6529 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
6530 	free(tmp_branch_name);
6531 	return NULL;
6532 }
6533 
6534 static const struct got_error *
6535 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
6536     const char *diff_path, char **logmsg, void *arg)
6537 {
6538 	*logmsg = arg;
6539 	return NULL;
6540 }
6541 
6542 static const struct got_error *
6543 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
6544     const char *path, struct got_object_id *blob_id,
6545     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
6546     int dirfd, const char *de_name)
6547 {
6548 	return NULL;
6549 }
6550 
6551 struct collect_merged_paths_arg {
6552 	got_worktree_checkout_cb progress_cb;
6553 	void *progress_arg;
6554 	struct got_pathlist_head *merged_paths;
6555 };
6556 
6557 static const struct got_error *
6558 collect_merged_paths(void *arg, unsigned char status, const char *path)
6559 {
6560 	const struct got_error *err;
6561 	struct collect_merged_paths_arg *a = arg;
6562 	char *p;
6563 	struct got_pathlist_entry *new;
6564 
6565 	err = (*a->progress_cb)(a->progress_arg, status, path);
6566 	if (err)
6567 		return err;
6568 
6569 	if (status != GOT_STATUS_MERGE &&
6570 	    status != GOT_STATUS_ADD &&
6571 	    status != GOT_STATUS_DELETE &&
6572 	    status != GOT_STATUS_CONFLICT)
6573 		return NULL;
6574 
6575 	p = strdup(path);
6576 	if (p == NULL)
6577 		return got_error_from_errno("strdup");
6578 
6579 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
6580 	if (err || new == NULL)
6581 		free(p);
6582 	return err;
6583 }
6584 
6585 static const struct got_error *
6586 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
6587     int is_rebase, struct got_repository *repo)
6588 {
6589 	const struct got_error *err;
6590 	struct got_reference *commit_ref = NULL;
6591 
6592 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6593 	if (err) {
6594 		if (err->code != GOT_ERR_NOT_REF)
6595 			goto done;
6596 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
6597 		if (err)
6598 			goto done;
6599 		err = got_ref_write(commit_ref, repo);
6600 		if (err)
6601 			goto done;
6602 	} else if (is_rebase) {
6603 		struct got_object_id *stored_id;
6604 		int cmp;
6605 
6606 		err = got_ref_resolve(&stored_id, repo, commit_ref);
6607 		if (err)
6608 			goto done;
6609 		cmp = got_object_id_cmp(commit_id, stored_id);
6610 		free(stored_id);
6611 		if (cmp != 0) {
6612 			err = got_error(GOT_ERR_REBASE_COMMITID);
6613 			goto done;
6614 		}
6615 	}
6616 done:
6617 	if (commit_ref)
6618 		got_ref_close(commit_ref);
6619 	return err;
6620 }
6621 
6622 static const struct got_error *
6623 rebase_merge_files(struct got_pathlist_head *merged_paths,
6624     const char *commit_ref_name, struct got_worktree *worktree,
6625     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
6626     struct got_object_id *commit_id, struct got_repository *repo,
6627     got_worktree_checkout_cb progress_cb, void *progress_arg,
6628     got_cancel_cb cancel_cb, void *cancel_arg)
6629 {
6630 	const struct got_error *err;
6631 	struct got_reference *commit_ref = NULL;
6632 	struct collect_merged_paths_arg cmp_arg;
6633 	char *fileindex_path;
6634 
6635 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6636 
6637 	err = get_fileindex_path(&fileindex_path, worktree);
6638 	if (err)
6639 		return err;
6640 
6641 	cmp_arg.progress_cb = progress_cb;
6642 	cmp_arg.progress_arg = progress_arg;
6643 	cmp_arg.merged_paths = merged_paths;
6644 	err = merge_files(worktree, fileindex, fileindex_path,
6645 	    parent_commit_id, commit_id, repo, collect_merged_paths,
6646 	    &cmp_arg, cancel_cb, cancel_arg);
6647 	if (commit_ref)
6648 		got_ref_close(commit_ref);
6649 	return err;
6650 }
6651 
6652 const struct got_error *
6653 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
6654     struct got_worktree *worktree, struct got_fileindex *fileindex,
6655     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6656     struct got_repository *repo,
6657     got_worktree_checkout_cb progress_cb, void *progress_arg,
6658     got_cancel_cb cancel_cb, void *cancel_arg)
6659 {
6660 	const struct got_error *err;
6661 	char *commit_ref_name;
6662 
6663 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6664 	if (err)
6665 		return err;
6666 
6667 	err = store_commit_id(commit_ref_name, commit_id, 1, repo);
6668 	if (err)
6669 		goto done;
6670 
6671 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6672 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6673 	    progress_arg, cancel_cb, cancel_arg);
6674 done:
6675 	free(commit_ref_name);
6676 	return err;
6677 }
6678 
6679 const struct got_error *
6680 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
6681     struct got_worktree *worktree, struct got_fileindex *fileindex,
6682     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6683     struct got_repository *repo,
6684     got_worktree_checkout_cb progress_cb, void *progress_arg,
6685     got_cancel_cb cancel_cb, void *cancel_arg)
6686 {
6687 	const struct got_error *err;
6688 	char *commit_ref_name;
6689 
6690 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6691 	if (err)
6692 		return err;
6693 
6694 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
6695 	if (err)
6696 		goto done;
6697 
6698 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6699 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6700 	    progress_arg, cancel_cb, cancel_arg);
6701 done:
6702 	free(commit_ref_name);
6703 	return err;
6704 }
6705 
6706 static const struct got_error *
6707 rebase_commit(struct got_object_id **new_commit_id,
6708     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
6709     struct got_worktree *worktree, struct got_fileindex *fileindex,
6710     struct got_reference *tmp_branch, const char *committer,
6711     struct got_commit_object *orig_commit, const char *new_logmsg,
6712     struct got_repository *repo)
6713 {
6714 	const struct got_error *err, *sync_err;
6715 	struct got_pathlist_head commitable_paths;
6716 	struct collect_commitables_arg cc_arg;
6717 	char *fileindex_path = NULL;
6718 	struct got_reference *head_ref = NULL;
6719 	struct got_object_id *head_commit_id = NULL;
6720 	char *logmsg = NULL;
6721 
6722 	memset(&cc_arg, 0, sizeof(cc_arg));
6723 	TAILQ_INIT(&commitable_paths);
6724 	*new_commit_id = NULL;
6725 
6726 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6727 
6728 	err = get_fileindex_path(&fileindex_path, worktree);
6729 	if (err)
6730 		return err;
6731 
6732 	cc_arg.commitable_paths = &commitable_paths;
6733 	cc_arg.worktree = worktree;
6734 	cc_arg.repo = repo;
6735 	cc_arg.have_staged_files = 0;
6736 	/*
6737 	 * If possible get the status of individual files directly to
6738 	 * avoid crawling the entire work tree once per rebased commit.
6739 	 *
6740 	 * Ideally, merged_paths would contain a list of commitables
6741 	 * we could use so we could skip worktree_status() entirely.
6742 	 * However, we would then need carefully keep track of cumulative
6743 	 * effects of operations such as file additions and deletions
6744 	 * in 'got histedit -f' (folding multiple commits into one),
6745 	 * and this extra complexity is not really worth it.
6746 	 */
6747 	if (merged_paths) {
6748 		struct got_pathlist_entry *pe;
6749 		TAILQ_FOREACH(pe, merged_paths, entry) {
6750 			err = worktree_status(worktree, pe->path, fileindex,
6751 			    repo, collect_commitables, &cc_arg, NULL, NULL, 1,
6752 			    0);
6753 			if (err)
6754 				goto done;
6755 		}
6756 	} else {
6757 		err = worktree_status(worktree, "", fileindex, repo,
6758 		    collect_commitables, &cc_arg, NULL, NULL, 1, 0);
6759 		if (err)
6760 			goto done;
6761 	}
6762 
6763 	if (TAILQ_EMPTY(&commitable_paths)) {
6764 		/* No-op change; commit will be elided. */
6765 		err = got_ref_delete(commit_ref, repo);
6766 		if (err)
6767 			goto done;
6768 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6769 		goto done;
6770 	}
6771 
6772 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6773 	if (err)
6774 		goto done;
6775 
6776 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6777 	if (err)
6778 		goto done;
6779 
6780 	if (new_logmsg) {
6781 		logmsg = strdup(new_logmsg);
6782 		if (logmsg == NULL) {
6783 			err = got_error_from_errno("strdup");
6784 			goto done;
6785 		}
6786 	} else {
6787 		err = got_object_commit_get_logmsg(&logmsg, orig_commit);
6788 		if (err)
6789 			goto done;
6790 	}
6791 
6792 	/* NB: commit_worktree will call free(logmsg) */
6793 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
6794 	    NULL, worktree, got_object_commit_get_author(orig_commit),
6795 	    committer ? committer :
6796 	    got_object_commit_get_committer(orig_commit), NULL,
6797 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
6798 	if (err)
6799 		goto done;
6800 
6801 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
6802 	if (err)
6803 		goto done;
6804 
6805 	err = got_ref_delete(commit_ref, repo);
6806 	if (err)
6807 		goto done;
6808 
6809 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6810 	    *new_commit_id, fileindex, 0);
6811 	sync_err = sync_fileindex(fileindex, fileindex_path);
6812 	if (sync_err && err == NULL)
6813 		err = sync_err;
6814 done:
6815 	free(fileindex_path);
6816 	free(head_commit_id);
6817 	if (head_ref)
6818 		got_ref_close(head_ref);
6819 	if (err) {
6820 		free(*new_commit_id);
6821 		*new_commit_id = NULL;
6822 	}
6823 	return err;
6824 }
6825 
6826 const struct got_error *
6827 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
6828     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6829     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6830     const char *committer, struct got_commit_object *orig_commit,
6831     struct got_object_id *orig_commit_id, struct got_repository *repo)
6832 {
6833 	const struct got_error *err;
6834 	char *commit_ref_name;
6835 	struct got_reference *commit_ref = NULL;
6836 	struct got_object_id *commit_id = NULL;
6837 
6838 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6839 	if (err)
6840 		return err;
6841 
6842 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6843 	if (err)
6844 		goto done;
6845 	err = got_ref_resolve(&commit_id, repo, commit_ref);
6846 	if (err)
6847 		goto done;
6848 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
6849 		err = got_error(GOT_ERR_REBASE_COMMITID);
6850 		goto done;
6851 	}
6852 
6853 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6854 	    worktree, fileindex, tmp_branch, committer, orig_commit,
6855 	    NULL, repo);
6856 done:
6857 	if (commit_ref)
6858 		got_ref_close(commit_ref);
6859 	free(commit_ref_name);
6860 	free(commit_id);
6861 	return err;
6862 }
6863 
6864 const struct got_error *
6865 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
6866     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6867     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6868     const char *committer, struct got_commit_object *orig_commit,
6869     struct got_object_id *orig_commit_id, const char *new_logmsg,
6870     struct got_repository *repo)
6871 {
6872 	const struct got_error *err;
6873 	char *commit_ref_name;
6874 	struct got_reference *commit_ref = NULL;
6875 
6876 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6877 	if (err)
6878 		return err;
6879 
6880 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6881 	if (err)
6882 		goto done;
6883 
6884 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6885 	    worktree, fileindex, tmp_branch, committer, orig_commit,
6886 	    new_logmsg, repo);
6887 done:
6888 	if (commit_ref)
6889 		got_ref_close(commit_ref);
6890 	free(commit_ref_name);
6891 	return err;
6892 }
6893 
6894 const struct got_error *
6895 got_worktree_rebase_postpone(struct got_worktree *worktree,
6896     struct got_fileindex *fileindex)
6897 {
6898 	if (fileindex)
6899 		got_fileindex_free(fileindex);
6900 	return lock_worktree(worktree, LOCK_SH);
6901 }
6902 
6903 static const struct got_error *
6904 delete_ref(const char *name, struct got_repository *repo)
6905 {
6906 	const struct got_error *err;
6907 	struct got_reference *ref;
6908 
6909 	err = got_ref_open(&ref, repo, name, 0);
6910 	if (err) {
6911 		if (err->code == GOT_ERR_NOT_REF)
6912 			return NULL;
6913 		return err;
6914 	}
6915 
6916 	err = got_ref_delete(ref, repo);
6917 	got_ref_close(ref);
6918 	return err;
6919 }
6920 
6921 static const struct got_error *
6922 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
6923 {
6924 	const struct got_error *err;
6925 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
6926 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
6927 
6928 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6929 	if (err)
6930 		goto done;
6931 	err = delete_ref(tmp_branch_name, repo);
6932 	if (err)
6933 		goto done;
6934 
6935 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6936 	if (err)
6937 		goto done;
6938 	err = delete_ref(new_base_branch_ref_name, repo);
6939 	if (err)
6940 		goto done;
6941 
6942 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6943 	if (err)
6944 		goto done;
6945 	err = delete_ref(branch_ref_name, repo);
6946 	if (err)
6947 		goto done;
6948 
6949 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6950 	if (err)
6951 		goto done;
6952 	err = delete_ref(commit_ref_name, repo);
6953 	if (err)
6954 		goto done;
6955 
6956 done:
6957 	free(tmp_branch_name);
6958 	free(new_base_branch_ref_name);
6959 	free(branch_ref_name);
6960 	free(commit_ref_name);
6961 	return err;
6962 }
6963 
6964 static const struct got_error *
6965 create_backup_ref(const char *backup_ref_prefix, struct got_reference *branch,
6966     struct got_object_id *new_commit_id, struct got_repository *repo)
6967 {
6968 	const struct got_error *err;
6969 	struct got_reference *ref = NULL;
6970 	struct got_object_id *old_commit_id = NULL;
6971 	const char *branch_name = NULL;
6972 	char *new_id_str = NULL;
6973 	char *refname = NULL;
6974 
6975 	branch_name = got_ref_get_name(branch);
6976 	if (strncmp(branch_name, "refs/heads/", 11) != 0)
6977 		return got_error(GOT_ERR_BAD_REF_NAME); /* should not happen */
6978 	branch_name += 11;
6979 
6980 	err = got_object_id_str(&new_id_str, new_commit_id);
6981 	if (err)
6982 		return err;
6983 
6984 	if (asprintf(&refname, "%s/%s/%s", backup_ref_prefix, branch_name,
6985 	    new_id_str) == -1) {
6986 		err = got_error_from_errno("asprintf");
6987 		goto done;
6988 	}
6989 
6990 	err = got_ref_resolve(&old_commit_id, repo, branch);
6991 	if (err)
6992 		goto done;
6993 
6994 	err = got_ref_alloc(&ref, refname, old_commit_id);
6995 	if (err)
6996 		goto done;
6997 
6998 	err = got_ref_write(ref, repo);
6999 done:
7000 	free(new_id_str);
7001 	free(refname);
7002 	free(old_commit_id);
7003 	if (ref)
7004 		got_ref_close(ref);
7005 	return err;
7006 }
7007 
7008 const struct got_error *
7009 got_worktree_rebase_complete(struct got_worktree *worktree,
7010     struct got_fileindex *fileindex, struct got_reference *new_base_branch,
7011     struct got_reference *tmp_branch, struct got_reference *rebased_branch,
7012     struct got_repository *repo, int create_backup)
7013 {
7014 	const struct got_error *err, *unlockerr, *sync_err;
7015 	struct got_object_id *new_head_commit_id = NULL;
7016 	char *fileindex_path = NULL;
7017 
7018 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7019 	if (err)
7020 		return err;
7021 
7022 	if (create_backup) {
7023 		err = create_backup_ref(GOT_WORKTREE_REBASE_BACKUP_REF_PREFIX,
7024 		    rebased_branch, new_head_commit_id, repo);
7025 		if (err)
7026 			goto done;
7027 	}
7028 
7029 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
7030 	if (err)
7031 		goto done;
7032 
7033 	err = got_ref_write(rebased_branch, repo);
7034 	if (err)
7035 		goto done;
7036 
7037 	err = got_worktree_set_head_ref(worktree, rebased_branch);
7038 	if (err)
7039 		goto done;
7040 
7041 	err = delete_rebase_refs(worktree, repo);
7042 	if (err)
7043 		goto done;
7044 
7045 	err = get_fileindex_path(&fileindex_path, worktree);
7046 	if (err)
7047 		goto done;
7048 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7049 	sync_err = sync_fileindex(fileindex, fileindex_path);
7050 	if (sync_err && err == NULL)
7051 		err = sync_err;
7052 done:
7053 	got_fileindex_free(fileindex);
7054 	free(fileindex_path);
7055 	free(new_head_commit_id);
7056 	unlockerr = lock_worktree(worktree, LOCK_SH);
7057 	if (unlockerr && err == NULL)
7058 		err = unlockerr;
7059 	return err;
7060 }
7061 
7062 const struct got_error *
7063 got_worktree_rebase_abort(struct got_worktree *worktree,
7064     struct got_fileindex *fileindex, struct got_repository *repo,
7065     struct got_reference *new_base_branch,
7066     got_worktree_checkout_cb progress_cb, void *progress_arg)
7067 {
7068 	const struct got_error *err, *unlockerr, *sync_err;
7069 	struct got_reference *resolved = NULL;
7070 	struct got_object_id *commit_id = NULL;
7071 	struct got_commit_object *commit = NULL;
7072 	char *fileindex_path = NULL;
7073 	struct revert_file_args rfa;
7074 	struct got_object_id *tree_id = NULL;
7075 
7076 	err = lock_worktree(worktree, LOCK_EX);
7077 	if (err)
7078 		return err;
7079 
7080 	err = got_object_open_as_commit(&commit, repo,
7081 	    worktree->base_commit_id);
7082 	if (err)
7083 		goto done;
7084 
7085 	err = got_ref_open(&resolved, repo,
7086 	    got_ref_get_symref_target(new_base_branch), 0);
7087 	if (err)
7088 		goto done;
7089 
7090 	err = got_worktree_set_head_ref(worktree, resolved);
7091 	if (err)
7092 		goto done;
7093 
7094 	/*
7095 	 * XXX commits to the base branch could have happened while
7096 	 * we were busy rebasing; should we store the original commit ID
7097 	 * when rebase begins and read it back here?
7098 	 */
7099 	err = got_ref_resolve(&commit_id, repo, resolved);
7100 	if (err)
7101 		goto done;
7102 
7103 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7104 	if (err)
7105 		goto done;
7106 
7107 	err = got_object_id_by_path(&tree_id, repo, commit,
7108 	    worktree->path_prefix);
7109 	if (err)
7110 		goto done;
7111 
7112 	err = delete_rebase_refs(worktree, repo);
7113 	if (err)
7114 		goto done;
7115 
7116 	err = get_fileindex_path(&fileindex_path, worktree);
7117 	if (err)
7118 		goto done;
7119 
7120 	rfa.worktree = worktree;
7121 	rfa.fileindex = fileindex;
7122 	rfa.progress_cb = progress_cb;
7123 	rfa.progress_arg = progress_arg;
7124 	rfa.patch_cb = NULL;
7125 	rfa.patch_arg = NULL;
7126 	rfa.repo = repo;
7127 	rfa.unlink_added_files = 0;
7128 	err = worktree_status(worktree, "", fileindex, repo,
7129 	    revert_file, &rfa, NULL, NULL, 1, 0);
7130 	if (err)
7131 		goto sync;
7132 
7133 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7134 	    repo, progress_cb, progress_arg, NULL, NULL);
7135 sync:
7136 	sync_err = sync_fileindex(fileindex, fileindex_path);
7137 	if (sync_err && err == NULL)
7138 		err = sync_err;
7139 done:
7140 	got_ref_close(resolved);
7141 	free(tree_id);
7142 	free(commit_id);
7143 	if (commit)
7144 		got_object_commit_close(commit);
7145 	if (fileindex)
7146 		got_fileindex_free(fileindex);
7147 	free(fileindex_path);
7148 
7149 	unlockerr = lock_worktree(worktree, LOCK_SH);
7150 	if (unlockerr && err == NULL)
7151 		err = unlockerr;
7152 	return err;
7153 }
7154 
7155 const struct got_error *
7156 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
7157     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
7158     struct got_fileindex **fileindex, struct got_worktree *worktree,
7159     struct got_repository *repo)
7160 {
7161 	const struct got_error *err = NULL;
7162 	char *tmp_branch_name = NULL;
7163 	char *branch_ref_name = NULL;
7164 	char *base_commit_ref_name = NULL;
7165 	char *fileindex_path = NULL;
7166 	struct check_rebase_ok_arg ok_arg;
7167 	struct got_reference *wt_branch = NULL;
7168 	struct got_reference *base_commit_ref = NULL;
7169 
7170 	*tmp_branch = NULL;
7171 	*branch_ref = NULL;
7172 	*base_commit_id = NULL;
7173 	*fileindex = NULL;
7174 
7175 	err = lock_worktree(worktree, LOCK_EX);
7176 	if (err)
7177 		return err;
7178 
7179 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7180 	if (err)
7181 		goto done;
7182 
7183 	ok_arg.worktree = worktree;
7184 	ok_arg.repo = repo;
7185 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7186 	    &ok_arg);
7187 	if (err)
7188 		goto done;
7189 
7190 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7191 	if (err)
7192 		goto done;
7193 
7194 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7195 	if (err)
7196 		goto done;
7197 
7198 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7199 	    worktree);
7200 	if (err)
7201 		goto done;
7202 
7203 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
7204 	    0);
7205 	if (err)
7206 		goto done;
7207 
7208 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
7209 	if (err)
7210 		goto done;
7211 
7212 	err = got_ref_write(*branch_ref, repo);
7213 	if (err)
7214 		goto done;
7215 
7216 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
7217 	    worktree->base_commit_id);
7218 	if (err)
7219 		goto done;
7220 	err = got_ref_write(base_commit_ref, repo);
7221 	if (err)
7222 		goto done;
7223 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
7224 	if (*base_commit_id == NULL) {
7225 		err = got_error_from_errno("got_object_id_dup");
7226 		goto done;
7227 	}
7228 
7229 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
7230 	    worktree->base_commit_id);
7231 	if (err)
7232 		goto done;
7233 	err = got_ref_write(*tmp_branch, repo);
7234 	if (err)
7235 		goto done;
7236 
7237 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
7238 	if (err)
7239 		goto done;
7240 done:
7241 	free(fileindex_path);
7242 	free(tmp_branch_name);
7243 	free(branch_ref_name);
7244 	free(base_commit_ref_name);
7245 	if (wt_branch)
7246 		got_ref_close(wt_branch);
7247 	if (err) {
7248 		if (*branch_ref) {
7249 			got_ref_close(*branch_ref);
7250 			*branch_ref = NULL;
7251 		}
7252 		if (*tmp_branch) {
7253 			got_ref_close(*tmp_branch);
7254 			*tmp_branch = NULL;
7255 		}
7256 		free(*base_commit_id);
7257 		if (*fileindex) {
7258 			got_fileindex_free(*fileindex);
7259 			*fileindex = NULL;
7260 		}
7261 		lock_worktree(worktree, LOCK_SH);
7262 	}
7263 	return err;
7264 }
7265 
7266 const struct got_error *
7267 got_worktree_histedit_postpone(struct got_worktree *worktree,
7268     struct got_fileindex *fileindex)
7269 {
7270 	if (fileindex)
7271 		got_fileindex_free(fileindex);
7272 	return lock_worktree(worktree, LOCK_SH);
7273 }
7274 
7275 const struct got_error *
7276 got_worktree_histedit_in_progress(int *in_progress,
7277     struct got_worktree *worktree)
7278 {
7279 	const struct got_error *err;
7280 	char *tmp_branch_name = NULL;
7281 
7282 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7283 	if (err)
7284 		return err;
7285 
7286 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
7287 	free(tmp_branch_name);
7288 	return NULL;
7289 }
7290 
7291 const struct got_error *
7292 got_worktree_histedit_continue(struct got_object_id **commit_id,
7293     struct got_reference **tmp_branch, struct got_reference **branch_ref,
7294     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
7295     struct got_worktree *worktree, struct got_repository *repo)
7296 {
7297 	const struct got_error *err;
7298 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
7299 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
7300 	struct got_reference *commit_ref = NULL;
7301 	struct got_reference *base_commit_ref = NULL;
7302 	char *fileindex_path = NULL;
7303 	int have_staged_files = 0;
7304 
7305 	*commit_id = NULL;
7306 	*tmp_branch = NULL;
7307 	*base_commit_id = NULL;
7308 	*fileindex = NULL;
7309 
7310 	err = lock_worktree(worktree, LOCK_EX);
7311 	if (err)
7312 		return err;
7313 
7314 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7315 	if (err)
7316 		goto done;
7317 
7318 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
7319 	    &have_staged_files);
7320 	if (err && err->code != GOT_ERR_CANCELLED)
7321 		goto done;
7322 	if (have_staged_files) {
7323 		err = got_error(GOT_ERR_STAGED_PATHS);
7324 		goto done;
7325 	}
7326 
7327 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7328 	if (err)
7329 		goto done;
7330 
7331 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7332 	if (err)
7333 		goto done;
7334 
7335 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7336 	if (err)
7337 		goto done;
7338 
7339 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7340 	    worktree);
7341 	if (err)
7342 		goto done;
7343 
7344 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
7345 	if (err)
7346 		goto done;
7347 
7348 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
7349 	if (err)
7350 		goto done;
7351 	err = got_ref_resolve(commit_id, repo, commit_ref);
7352 	if (err)
7353 		goto done;
7354 
7355 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
7356 	if (err)
7357 		goto done;
7358 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
7359 	if (err)
7360 		goto done;
7361 
7362 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
7363 	if (err)
7364 		goto done;
7365 done:
7366 	free(commit_ref_name);
7367 	free(branch_ref_name);
7368 	free(fileindex_path);
7369 	if (commit_ref)
7370 		got_ref_close(commit_ref);
7371 	if (base_commit_ref)
7372 		got_ref_close(base_commit_ref);
7373 	if (err) {
7374 		free(*commit_id);
7375 		*commit_id = NULL;
7376 		free(*base_commit_id);
7377 		*base_commit_id = NULL;
7378 		if (*tmp_branch) {
7379 			got_ref_close(*tmp_branch);
7380 			*tmp_branch = NULL;
7381 		}
7382 		if (*fileindex) {
7383 			got_fileindex_free(*fileindex);
7384 			*fileindex = NULL;
7385 		}
7386 		lock_worktree(worktree, LOCK_EX);
7387 	}
7388 	return err;
7389 }
7390 
7391 static const struct got_error *
7392 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
7393 {
7394 	const struct got_error *err;
7395 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
7396 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
7397 
7398 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
7399 	if (err)
7400 		goto done;
7401 	err = delete_ref(tmp_branch_name, repo);
7402 	if (err)
7403 		goto done;
7404 
7405 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
7406 	    worktree);
7407 	if (err)
7408 		goto done;
7409 	err = delete_ref(base_commit_ref_name, repo);
7410 	if (err)
7411 		goto done;
7412 
7413 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
7414 	if (err)
7415 		goto done;
7416 	err = delete_ref(branch_ref_name, repo);
7417 	if (err)
7418 		goto done;
7419 
7420 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7421 	if (err)
7422 		goto done;
7423 	err = delete_ref(commit_ref_name, repo);
7424 	if (err)
7425 		goto done;
7426 done:
7427 	free(tmp_branch_name);
7428 	free(base_commit_ref_name);
7429 	free(branch_ref_name);
7430 	free(commit_ref_name);
7431 	return err;
7432 }
7433 
7434 const struct got_error *
7435 got_worktree_histedit_abort(struct got_worktree *worktree,
7436     struct got_fileindex *fileindex, struct got_repository *repo,
7437     struct got_reference *branch, struct got_object_id *base_commit_id,
7438     got_worktree_checkout_cb progress_cb, void *progress_arg)
7439 {
7440 	const struct got_error *err, *unlockerr, *sync_err;
7441 	struct got_reference *resolved = NULL;
7442 	char *fileindex_path = NULL;
7443 	struct got_commit_object *commit = NULL;
7444 	struct got_object_id *tree_id = NULL;
7445 	struct revert_file_args rfa;
7446 
7447 	err = lock_worktree(worktree, LOCK_EX);
7448 	if (err)
7449 		return err;
7450 
7451 	err = got_object_open_as_commit(&commit, repo,
7452 	    worktree->base_commit_id);
7453 	if (err)
7454 		goto done;
7455 
7456 	err = got_ref_open(&resolved, repo,
7457 	    got_ref_get_symref_target(branch), 0);
7458 	if (err)
7459 		goto done;
7460 
7461 	err = got_worktree_set_head_ref(worktree, resolved);
7462 	if (err)
7463 		goto done;
7464 
7465 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
7466 	if (err)
7467 		goto done;
7468 
7469 	err = got_object_id_by_path(&tree_id, repo, commit,
7470 	    worktree->path_prefix);
7471 	if (err)
7472 		goto done;
7473 
7474 	err = delete_histedit_refs(worktree, repo);
7475 	if (err)
7476 		goto done;
7477 
7478 	err = get_fileindex_path(&fileindex_path, worktree);
7479 	if (err)
7480 		goto done;
7481 
7482 	rfa.worktree = worktree;
7483 	rfa.fileindex = fileindex;
7484 	rfa.progress_cb = progress_cb;
7485 	rfa.progress_arg = progress_arg;
7486 	rfa.patch_cb = NULL;
7487 	rfa.patch_arg = NULL;
7488 	rfa.repo = repo;
7489 	rfa.unlink_added_files = 0;
7490 	err = worktree_status(worktree, "", fileindex, repo,
7491 	    revert_file, &rfa, NULL, NULL, 1, 0);
7492 	if (err)
7493 		goto sync;
7494 
7495 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7496 	    repo, progress_cb, progress_arg, NULL, NULL);
7497 sync:
7498 	sync_err = sync_fileindex(fileindex, fileindex_path);
7499 	if (sync_err && err == NULL)
7500 		err = sync_err;
7501 done:
7502 	got_ref_close(resolved);
7503 	free(tree_id);
7504 	free(fileindex_path);
7505 
7506 	unlockerr = lock_worktree(worktree, LOCK_SH);
7507 	if (unlockerr && err == NULL)
7508 		err = unlockerr;
7509 	return err;
7510 }
7511 
7512 const struct got_error *
7513 got_worktree_histedit_complete(struct got_worktree *worktree,
7514     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
7515     struct got_reference *edited_branch, struct got_repository *repo)
7516 {
7517 	const struct got_error *err, *unlockerr, *sync_err;
7518 	struct got_object_id *new_head_commit_id = NULL;
7519 	struct got_reference *resolved = NULL;
7520 	char *fileindex_path = NULL;
7521 
7522 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7523 	if (err)
7524 		return err;
7525 
7526 	err = got_ref_open(&resolved, repo,
7527 	    got_ref_get_symref_target(edited_branch), 0);
7528 	if (err)
7529 		goto done;
7530 
7531 	err = create_backup_ref(GOT_WORKTREE_HISTEDIT_BACKUP_REF_PREFIX,
7532 	    resolved, new_head_commit_id, repo);
7533 	if (err)
7534 		goto done;
7535 
7536 	err = got_ref_change_ref(resolved, new_head_commit_id);
7537 	if (err)
7538 		goto done;
7539 
7540 	err = got_ref_write(resolved, repo);
7541 	if (err)
7542 		goto done;
7543 
7544 	err = got_worktree_set_head_ref(worktree, resolved);
7545 	if (err)
7546 		goto done;
7547 
7548 	err = delete_histedit_refs(worktree, repo);
7549 	if (err)
7550 		goto done;
7551 
7552 	err = get_fileindex_path(&fileindex_path, worktree);
7553 	if (err)
7554 		goto done;
7555 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7556 	sync_err = sync_fileindex(fileindex, fileindex_path);
7557 	if (sync_err && err == NULL)
7558 		err = sync_err;
7559 done:
7560 	got_fileindex_free(fileindex);
7561 	free(fileindex_path);
7562 	free(new_head_commit_id);
7563 	unlockerr = lock_worktree(worktree, LOCK_SH);
7564 	if (unlockerr && err == NULL)
7565 		err = unlockerr;
7566 	return err;
7567 }
7568 
7569 const struct got_error *
7570 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
7571     struct got_object_id *commit_id, struct got_repository *repo)
7572 {
7573 	const struct got_error *err;
7574 	char *commit_ref_name;
7575 
7576 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7577 	if (err)
7578 		return err;
7579 
7580 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
7581 	if (err)
7582 		goto done;
7583 
7584 	err = delete_ref(commit_ref_name, repo);
7585 done:
7586 	free(commit_ref_name);
7587 	return err;
7588 }
7589 
7590 const struct got_error *
7591 got_worktree_integrate_prepare(struct got_fileindex **fileindex,
7592     struct got_reference **branch_ref, struct got_reference **base_branch_ref,
7593     struct got_worktree *worktree, const char *refname,
7594     struct got_repository *repo)
7595 {
7596 	const struct got_error *err = NULL;
7597 	char *fileindex_path = NULL;
7598 	struct check_rebase_ok_arg ok_arg;
7599 
7600 	*fileindex = NULL;
7601 	*branch_ref = NULL;
7602 	*base_branch_ref = NULL;
7603 
7604 	err = lock_worktree(worktree, LOCK_EX);
7605 	if (err)
7606 		return err;
7607 
7608 	if (strcmp(refname, got_worktree_get_head_ref_name(worktree)) == 0) {
7609 		err = got_error_msg(GOT_ERR_SAME_BRANCH,
7610 		    "cannot integrate a branch into itself; "
7611 		    "update -b or different branch name required");
7612 		goto done;
7613 	}
7614 
7615 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7616 	if (err)
7617 		goto done;
7618 
7619 	/* Preconditions are the same as for rebase. */
7620 	ok_arg.worktree = worktree;
7621 	ok_arg.repo = repo;
7622 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7623 	    &ok_arg);
7624 	if (err)
7625 		goto done;
7626 
7627 	err = got_ref_open(branch_ref, repo, refname, 1);
7628 	if (err)
7629 		goto done;
7630 
7631 	err = got_ref_open(base_branch_ref, repo,
7632 	    got_worktree_get_head_ref_name(worktree), 1);
7633 done:
7634 	if (err) {
7635 		if (*branch_ref) {
7636 			got_ref_close(*branch_ref);
7637 			*branch_ref = NULL;
7638 		}
7639 		if (*base_branch_ref) {
7640 			got_ref_close(*base_branch_ref);
7641 			*base_branch_ref = NULL;
7642 		}
7643 		if (*fileindex) {
7644 			got_fileindex_free(*fileindex);
7645 			*fileindex = NULL;
7646 		}
7647 		lock_worktree(worktree, LOCK_SH);
7648 	}
7649 	return err;
7650 }
7651 
7652 const struct got_error *
7653 got_worktree_integrate_continue(struct got_worktree *worktree,
7654     struct got_fileindex *fileindex, struct got_repository *repo,
7655     struct got_reference *branch_ref, struct got_reference *base_branch_ref,
7656     got_worktree_checkout_cb progress_cb, void *progress_arg,
7657     got_cancel_cb cancel_cb, void *cancel_arg)
7658 {
7659 	const struct got_error *err = NULL, *sync_err, *unlockerr;
7660 	char *fileindex_path = NULL;
7661 	struct got_object_id *tree_id = NULL, *commit_id = NULL;
7662 	struct got_commit_object *commit =  NULL;
7663 
7664 	err = get_fileindex_path(&fileindex_path, worktree);
7665 	if (err)
7666 		goto done;
7667 
7668 	err = got_ref_resolve(&commit_id, repo, branch_ref);
7669 	if (err)
7670 		goto done;
7671 
7672 	err = got_object_open_as_commit(&commit, repo, commit_id);
7673 	if (err)
7674 		goto done;
7675 
7676 	err = got_object_id_by_path(&tree_id, repo, commit,
7677 	    worktree->path_prefix);
7678 	if (err)
7679 		goto done;
7680 
7681 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7682 	if (err)
7683 		goto done;
7684 
7685 	err = checkout_files(worktree, fileindex, "", tree_id, NULL, repo,
7686 	    progress_cb, progress_arg, cancel_cb, cancel_arg);
7687 	if (err)
7688 		goto sync;
7689 
7690 	err = got_ref_change_ref(base_branch_ref, commit_id);
7691 	if (err)
7692 		goto sync;
7693 
7694 	err = got_ref_write(base_branch_ref, repo);
7695 	if (err)
7696 		goto sync;
7697 
7698 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7699 sync:
7700 	sync_err = sync_fileindex(fileindex, fileindex_path);
7701 	if (sync_err && err == NULL)
7702 		err = sync_err;
7703 
7704 done:
7705 	unlockerr = got_ref_unlock(branch_ref);
7706 	if (unlockerr && err == NULL)
7707 		err = unlockerr;
7708 	got_ref_close(branch_ref);
7709 
7710 	unlockerr = got_ref_unlock(base_branch_ref);
7711 	if (unlockerr && err == NULL)
7712 		err = unlockerr;
7713 	got_ref_close(base_branch_ref);
7714 
7715 	got_fileindex_free(fileindex);
7716 	free(fileindex_path);
7717 	free(tree_id);
7718 	if (commit)
7719 		got_object_commit_close(commit);
7720 
7721 	unlockerr = lock_worktree(worktree, LOCK_SH);
7722 	if (unlockerr && err == NULL)
7723 		err = unlockerr;
7724 	return err;
7725 }
7726 
7727 const struct got_error *
7728 got_worktree_integrate_abort(struct got_worktree *worktree,
7729     struct got_fileindex *fileindex, struct got_repository *repo,
7730     struct got_reference *branch_ref, struct got_reference *base_branch_ref)
7731 {
7732 	const struct got_error *err = NULL, *unlockerr = NULL;
7733 
7734 	got_fileindex_free(fileindex);
7735 
7736 	err = lock_worktree(worktree, LOCK_SH);
7737 
7738 	unlockerr = got_ref_unlock(branch_ref);
7739 	if (unlockerr && err == NULL)
7740 		err = unlockerr;
7741 	got_ref_close(branch_ref);
7742 
7743 	unlockerr = got_ref_unlock(base_branch_ref);
7744 	if (unlockerr && err == NULL)
7745 		err = unlockerr;
7746 	got_ref_close(base_branch_ref);
7747 
7748 	return err;
7749 }
7750 
7751 const struct got_error *
7752 got_worktree_merge_postpone(struct got_worktree *worktree,
7753     struct got_fileindex *fileindex)
7754 {
7755 	const struct got_error *err, *sync_err;
7756 	char *fileindex_path = NULL;
7757 
7758 	err = get_fileindex_path(&fileindex_path, worktree);
7759 	if (err)
7760 		goto done;
7761 
7762 	sync_err = sync_fileindex(fileindex, fileindex_path);
7763 
7764 	err = lock_worktree(worktree, LOCK_SH);
7765 	if (sync_err && err == NULL)
7766 		err = sync_err;
7767 done:
7768 	got_fileindex_free(fileindex);
7769 	free(fileindex_path);
7770 	return err;
7771 }
7772 
7773 static const struct got_error *
7774 delete_merge_refs(struct got_worktree *worktree, struct got_repository *repo)
7775 {
7776 	const struct got_error *err;
7777 	char *branch_refname = NULL, *commit_refname = NULL;
7778 
7779 	err = get_merge_branch_ref_name(&branch_refname, worktree);
7780 	if (err)
7781 		goto done;
7782 	err = delete_ref(branch_refname, repo);
7783 	if (err)
7784 		goto done;
7785 
7786 	err = get_merge_commit_ref_name(&commit_refname, worktree);
7787 	if (err)
7788 		goto done;
7789 	err = delete_ref(commit_refname, repo);
7790 	if (err)
7791 		goto done;
7792 
7793 done:
7794 	free(branch_refname);
7795 	free(commit_refname);
7796 	return err;
7797 }
7798 
7799 struct merge_commit_msg_arg {
7800 	struct got_worktree *worktree;
7801 	const char *branch_name;
7802 };
7803 
7804 static const struct got_error *
7805 merge_commit_msg_cb(struct got_pathlist_head *commitable_paths,
7806     const char *diff_path, char **logmsg, void *arg)
7807 {
7808 	struct merge_commit_msg_arg *a = arg;
7809 
7810 	if (asprintf(logmsg, "merge %s into %s\n", a->branch_name,
7811 	    got_worktree_get_head_ref_name(a->worktree)) == -1)
7812 		return got_error_from_errno("asprintf");
7813 
7814 	return NULL;
7815 }
7816 
7817 
7818 const struct got_error *
7819 got_worktree_merge_branch(struct got_worktree *worktree,
7820     struct got_fileindex *fileindex,
7821     struct got_object_id *yca_commit_id,
7822     struct got_object_id *branch_tip,
7823     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
7824     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
7825 {
7826 	const struct got_error *err;
7827 	char *fileindex_path = NULL;
7828 
7829 	err = get_fileindex_path(&fileindex_path, worktree);
7830 	if (err)
7831 		goto done;
7832 
7833 	err = got_fileindex_for_each_entry_safe(fileindex, check_mixed_commits,
7834 	    worktree);
7835 	if (err)
7836 		goto done;
7837 
7838 	err = merge_files(worktree, fileindex, fileindex_path, yca_commit_id,
7839 	    branch_tip, repo, progress_cb, progress_arg,
7840 	    cancel_cb, cancel_arg);
7841 done:
7842 	free(fileindex_path);
7843 	return err;
7844 }
7845 
7846 const struct got_error *
7847 got_worktree_merge_commit(struct got_object_id **new_commit_id,
7848     struct got_worktree *worktree, struct got_fileindex *fileindex,
7849     const char *author, const char *committer, int allow_bad_symlinks,
7850     struct got_object_id *branch_tip, const char *branch_name,
7851     struct got_repository *repo,
7852     got_worktree_status_cb status_cb, void *status_arg)
7853 
7854 {
7855 	const struct got_error *err = NULL, *sync_err;
7856 	struct got_pathlist_head commitable_paths;
7857 	struct collect_commitables_arg cc_arg;
7858 	struct got_pathlist_entry *pe;
7859 	struct got_reference *head_ref = NULL;
7860 	struct got_object_id *head_commit_id = NULL;
7861 	int have_staged_files = 0;
7862 	struct merge_commit_msg_arg mcm_arg;
7863 	char *fileindex_path = NULL;
7864 
7865 	memset(&cc_arg, 0, sizeof(cc_arg));
7866 	*new_commit_id = NULL;
7867 
7868 	TAILQ_INIT(&commitable_paths);
7869 
7870 	err = get_fileindex_path(&fileindex_path, worktree);
7871 	if (err)
7872 		goto done;
7873 
7874 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
7875 	if (err)
7876 		goto done;
7877 
7878 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
7879 	if (err)
7880 		goto done;
7881 
7882 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
7883 	    &have_staged_files);
7884 	if (err && err->code != GOT_ERR_CANCELLED)
7885 		goto done;
7886 	if (have_staged_files) {
7887 		err = got_error(GOT_ERR_MERGE_STAGED_PATHS);
7888 		goto done;
7889 	}
7890 
7891 	cc_arg.commitable_paths = &commitable_paths;
7892 	cc_arg.worktree = worktree;
7893 	cc_arg.fileindex = fileindex;
7894 	cc_arg.repo = repo;
7895 	cc_arg.have_staged_files = have_staged_files;
7896 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
7897 	err = worktree_status(worktree, "", fileindex, repo,
7898 	    collect_commitables, &cc_arg, NULL, NULL, 1, 0);
7899 	if (err)
7900 		goto done;
7901 
7902 	if (TAILQ_EMPTY(&commitable_paths)) {
7903 		err = got_error_fmt(GOT_ERR_COMMIT_NO_CHANGES,
7904 		    "merge of %s cannot proceed", branch_name);
7905 		goto done;
7906 	}
7907 
7908 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
7909 		struct got_commitable *ct = pe->data;
7910 		const char *ct_path = ct->in_repo_path;
7911 
7912 		while (ct_path[0] == '/')
7913 			ct_path++;
7914 		err = check_out_of_date(ct_path, ct->status,
7915 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
7916 		    head_commit_id, repo, GOT_ERR_MERGE_COMMIT_OUT_OF_DATE);
7917 		if (err)
7918 			goto done;
7919 
7920 	}
7921 
7922 	mcm_arg.worktree = worktree;
7923 	mcm_arg.branch_name = branch_name;
7924 	err = commit_worktree(new_commit_id, &commitable_paths,
7925 	    head_commit_id, branch_tip, worktree, author, committer, NULL,
7926 	    merge_commit_msg_cb, &mcm_arg, status_cb, status_arg, repo);
7927 	if (err)
7928 		goto done;
7929 
7930 	err = update_fileindex_after_commit(worktree, &commitable_paths,
7931 	    *new_commit_id, fileindex, have_staged_files);
7932 	sync_err = sync_fileindex(fileindex, fileindex_path);
7933 	if (sync_err && err == NULL)
7934 		err = sync_err;
7935 done:
7936 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
7937 		struct got_commitable *ct = pe->data;
7938 
7939 		free_commitable(ct);
7940 	}
7941 	got_pathlist_free(&commitable_paths, GOT_PATHLIST_FREE_NONE);
7942 	free(fileindex_path);
7943 	return err;
7944 }
7945 
7946 const struct got_error *
7947 got_worktree_merge_complete(struct got_worktree *worktree,
7948     struct got_fileindex *fileindex, struct got_repository *repo)
7949 {
7950 	const struct got_error *err, *unlockerr, *sync_err;
7951 	char *fileindex_path = NULL;
7952 
7953 	err = delete_merge_refs(worktree, repo);
7954 	if (err)
7955 		goto done;
7956 
7957 	err = get_fileindex_path(&fileindex_path, worktree);
7958 	if (err)
7959 		goto done;
7960 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7961 	sync_err = sync_fileindex(fileindex, fileindex_path);
7962 	if (sync_err && err == NULL)
7963 		err = sync_err;
7964 done:
7965 	got_fileindex_free(fileindex);
7966 	free(fileindex_path);
7967 	unlockerr = lock_worktree(worktree, LOCK_SH);
7968 	if (unlockerr && err == NULL)
7969 		err = unlockerr;
7970 	return err;
7971 }
7972 
7973 const struct got_error *
7974 got_worktree_merge_in_progress(int *in_progress, struct got_worktree *worktree,
7975     struct got_repository *repo)
7976 {
7977 	const struct got_error *err;
7978 	char *branch_refname = NULL;
7979 	struct got_reference *branch_ref = NULL;
7980 
7981 	*in_progress = 0;
7982 
7983 	err = get_merge_branch_ref_name(&branch_refname, worktree);
7984 	if (err)
7985 		return err;
7986 	err = got_ref_open(&branch_ref, repo, branch_refname, 0);
7987 	free(branch_refname);
7988 	if (err) {
7989 		if (err->code != GOT_ERR_NOT_REF)
7990 			return err;
7991 	} else
7992 		*in_progress = 1;
7993 
7994 	return NULL;
7995 }
7996 
7997 const struct got_error *got_worktree_merge_prepare(
7998     struct got_fileindex **fileindex, struct got_worktree *worktree,
7999     struct got_reference *branch, struct got_repository *repo)
8000 {
8001 	const struct got_error *err = NULL;
8002 	char *fileindex_path = NULL;
8003 	char *branch_refname = NULL, *commit_refname = NULL;
8004 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
8005 	struct got_reference *commit_ref = NULL;
8006 	struct got_object_id *branch_tip = NULL, *wt_branch_tip = NULL;
8007 	struct check_rebase_ok_arg ok_arg;
8008 
8009 	*fileindex = NULL;
8010 
8011 	err = lock_worktree(worktree, LOCK_EX);
8012 	if (err)
8013 		return err;
8014 
8015 	err = open_fileindex(fileindex, &fileindex_path, worktree);
8016 	if (err)
8017 		goto done;
8018 
8019 	/* Preconditions are the same as for rebase. */
8020 	ok_arg.worktree = worktree;
8021 	ok_arg.repo = repo;
8022 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
8023 	    &ok_arg);
8024 	if (err)
8025 		goto done;
8026 
8027 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8028 	if (err)
8029 		return err;
8030 
8031 	err = get_merge_commit_ref_name(&commit_refname, worktree);
8032 	if (err)
8033 		return err;
8034 
8035 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
8036 	    0);
8037 	if (err)
8038 		goto done;
8039 
8040 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
8041 	if (err)
8042 		goto done;
8043 
8044 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
8045 		err = got_error(GOT_ERR_MERGE_OUT_OF_DATE);
8046 		goto done;
8047 	}
8048 
8049 	err = got_ref_resolve(&branch_tip, repo, branch);
8050 	if (err)
8051 		goto done;
8052 
8053 	err = got_ref_alloc_symref(&branch_ref, branch_refname, branch);
8054 	if (err)
8055 		goto done;
8056 	err = got_ref_write(branch_ref, repo);
8057 	if (err)
8058 		goto done;
8059 
8060 	err = got_ref_alloc(&commit_ref, commit_refname, branch_tip);
8061 	if (err)
8062 		goto done;
8063 	err = got_ref_write(commit_ref, repo);
8064 	if (err)
8065 		goto done;
8066 
8067 done:
8068 	free(branch_refname);
8069 	free(commit_refname);
8070 	free(fileindex_path);
8071 	if (branch_ref)
8072 		got_ref_close(branch_ref);
8073 	if (commit_ref)
8074 		got_ref_close(commit_ref);
8075 	if (wt_branch)
8076 		got_ref_close(wt_branch);
8077 	free(wt_branch_tip);
8078 	if (err) {
8079 		if (*fileindex) {
8080 			got_fileindex_free(*fileindex);
8081 			*fileindex = NULL;
8082 		}
8083 		lock_worktree(worktree, LOCK_SH);
8084 	}
8085 	return err;
8086 }
8087 
8088 const struct got_error *
8089 got_worktree_merge_continue(char **branch_name,
8090     struct got_object_id **branch_tip, struct got_fileindex **fileindex,
8091     struct got_worktree *worktree, struct got_repository *repo)
8092 {
8093 	const struct got_error *err;
8094 	char *commit_refname = NULL, *branch_refname = NULL;
8095 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
8096 	char *fileindex_path = NULL;
8097 	int have_staged_files = 0;
8098 
8099 	*branch_name = NULL;
8100 	*branch_tip = NULL;
8101 	*fileindex = NULL;
8102 
8103 	err = lock_worktree(worktree, LOCK_EX);
8104 	if (err)
8105 		return err;
8106 
8107 	err = open_fileindex(fileindex, &fileindex_path, worktree);
8108 	if (err)
8109 		goto done;
8110 
8111 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
8112 	    &have_staged_files);
8113 	if (err && err->code != GOT_ERR_CANCELLED)
8114 		goto done;
8115 	if (have_staged_files) {
8116 		err = got_error(GOT_ERR_STAGED_PATHS);
8117 		goto done;
8118 	}
8119 
8120 	err = get_merge_branch_ref_name(&branch_refname, worktree);
8121 	if (err)
8122 		goto done;
8123 
8124 	err = get_merge_commit_ref_name(&commit_refname, worktree);
8125 	if (err)
8126 		goto done;
8127 
8128 	err = got_ref_open(&branch_ref, repo, branch_refname, 0);
8129 	if (err)
8130 		goto done;
8131 
8132 	if (!got_ref_is_symbolic(branch_ref)) {
8133 		err = got_error_fmt(GOT_ERR_BAD_REF_TYPE,
8134 		    "%s is not a symbolic reference",
8135 		    got_ref_get_name(branch_ref));
8136 		goto done;
8137 	}
8138 	*branch_name = strdup(got_ref_get_symref_target(branch_ref));
8139 	if (*branch_name == NULL) {
8140 		err = got_error_from_errno("strdup");
8141 		goto done;
8142 	}
8143 
8144 	err = got_ref_open(&commit_ref, repo, commit_refname, 0);
8145 	if (err)
8146 		goto done;
8147 
8148 	err = got_ref_resolve(branch_tip, repo, commit_ref);
8149 	if (err)
8150 		goto done;
8151 done:
8152 	free(commit_refname);
8153 	free(branch_refname);
8154 	free(fileindex_path);
8155 	if (commit_ref)
8156 		got_ref_close(commit_ref);
8157 	if (branch_ref)
8158 		got_ref_close(branch_ref);
8159 	if (err) {
8160 		if (*branch_name) {
8161 			free(*branch_name);
8162 			*branch_name = NULL;
8163 		}
8164 		free(*branch_tip);
8165 		*branch_tip = NULL;
8166 		if (*fileindex) {
8167 			got_fileindex_free(*fileindex);
8168 			*fileindex = NULL;
8169 		}
8170 		lock_worktree(worktree, LOCK_SH);
8171 	}
8172 	return err;
8173 }
8174 
8175 const struct got_error *
8176 got_worktree_merge_abort(struct got_worktree *worktree,
8177     struct got_fileindex *fileindex, struct got_repository *repo,
8178     got_worktree_checkout_cb progress_cb, void *progress_arg)
8179 {
8180 	const struct got_error *err, *unlockerr, *sync_err;
8181 	struct got_object_id *commit_id = NULL;
8182 	struct got_commit_object *commit = NULL;
8183 	char *fileindex_path = NULL;
8184 	struct revert_file_args rfa;
8185 	struct got_object_id *tree_id = NULL;
8186 
8187 	err = got_object_open_as_commit(&commit, repo,
8188 	    worktree->base_commit_id);
8189 	if (err)
8190 		goto done;
8191 
8192 	err = got_object_id_by_path(&tree_id, repo, commit,
8193 	    worktree->path_prefix);
8194 	if (err)
8195 		goto done;
8196 
8197 	err = delete_merge_refs(worktree, repo);
8198 	if (err)
8199 		goto done;
8200 
8201 	err = get_fileindex_path(&fileindex_path, worktree);
8202 	if (err)
8203 		goto done;
8204 
8205 	rfa.worktree = worktree;
8206 	rfa.fileindex = fileindex;
8207 	rfa.progress_cb = progress_cb;
8208 	rfa.progress_arg = progress_arg;
8209 	rfa.patch_cb = NULL;
8210 	rfa.patch_arg = NULL;
8211 	rfa.repo = repo;
8212 	rfa.unlink_added_files = 1;
8213 	err = worktree_status(worktree, "", fileindex, repo,
8214 	    revert_file, &rfa, NULL, NULL, 1, 0);
8215 	if (err)
8216 		goto sync;
8217 
8218 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
8219 	    repo, progress_cb, progress_arg, NULL, NULL);
8220 sync:
8221 	sync_err = sync_fileindex(fileindex, fileindex_path);
8222 	if (sync_err && err == NULL)
8223 		err = sync_err;
8224 done:
8225 	free(tree_id);
8226 	free(commit_id);
8227 	if (commit)
8228 		got_object_commit_close(commit);
8229 	if (fileindex)
8230 		got_fileindex_free(fileindex);
8231 	free(fileindex_path);
8232 
8233 	unlockerr = lock_worktree(worktree, LOCK_SH);
8234 	if (unlockerr && err == NULL)
8235 		err = unlockerr;
8236 	return err;
8237 }
8238 
8239 struct check_stage_ok_arg {
8240 	struct got_object_id *head_commit_id;
8241 	struct got_worktree *worktree;
8242 	struct got_fileindex *fileindex;
8243 	struct got_repository *repo;
8244 	int have_changes;
8245 };
8246 
8247 static const struct got_error *
8248 check_stage_ok(void *arg, unsigned char status,
8249     unsigned char staged_status, const char *relpath,
8250     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8251     struct got_object_id *commit_id, int dirfd, const char *de_name)
8252 {
8253 	struct check_stage_ok_arg *a = arg;
8254 	const struct got_error *err = NULL;
8255 	struct got_fileindex_entry *ie;
8256 	struct got_object_id base_commit_id;
8257 	struct got_object_id *base_commit_idp = NULL;
8258 	char *in_repo_path = NULL, *p;
8259 
8260 	if (status == GOT_STATUS_UNVERSIONED ||
8261 	    status == GOT_STATUS_NO_CHANGE)
8262 		return NULL;
8263 	if (status == GOT_STATUS_NONEXISTENT)
8264 		return got_error_set_errno(ENOENT, relpath);
8265 
8266 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8267 	if (ie == NULL)
8268 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8269 
8270 	if (asprintf(&in_repo_path, "%s%s%s", a->worktree->path_prefix,
8271 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
8272 	    relpath) == -1)
8273 		return got_error_from_errno("asprintf");
8274 
8275 	if (got_fileindex_entry_has_commit(ie)) {
8276 		memcpy(base_commit_id.sha1, ie->commit_sha1,
8277 		    SHA1_DIGEST_LENGTH);
8278 		base_commit_idp = &base_commit_id;
8279 	}
8280 
8281 	if (status == GOT_STATUS_CONFLICT) {
8282 		err = got_error_path(ie->path, GOT_ERR_STAGE_CONFLICT);
8283 		goto done;
8284 	} else if (status != GOT_STATUS_ADD &&
8285 	    status != GOT_STATUS_MODIFY &&
8286 	    status != GOT_STATUS_DELETE) {
8287 		err = got_error_path(ie->path, GOT_ERR_FILE_STATUS);
8288 		goto done;
8289 	}
8290 
8291 	a->have_changes = 1;
8292 
8293 	p = in_repo_path;
8294 	while (p[0] == '/')
8295 		p++;
8296 	err = check_out_of_date(p, status, staged_status,
8297 	    blob_id, base_commit_idp, a->head_commit_id, a->repo,
8298 	    GOT_ERR_STAGE_OUT_OF_DATE);
8299 done:
8300 	free(in_repo_path);
8301 	return err;
8302 }
8303 
8304 struct stage_path_arg {
8305 	struct got_worktree *worktree;
8306 	struct got_fileindex *fileindex;
8307 	struct got_repository *repo;
8308 	got_worktree_status_cb status_cb;
8309 	void *status_arg;
8310 	got_worktree_patch_cb patch_cb;
8311 	void *patch_arg;
8312 	int staged_something;
8313 	int allow_bad_symlinks;
8314 };
8315 
8316 static const struct got_error *
8317 stage_path(void *arg, unsigned char status,
8318     unsigned char staged_status, const char *relpath,
8319     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8320     struct got_object_id *commit_id, int dirfd, const char *de_name)
8321 {
8322 	struct stage_path_arg *a = arg;
8323 	const struct got_error *err = NULL;
8324 	struct got_fileindex_entry *ie;
8325 	char *ondisk_path = NULL, *path_content = NULL;
8326 	uint32_t stage;
8327 	struct got_object_id *new_staged_blob_id = NULL;
8328 	struct stat sb;
8329 
8330 	if (status == GOT_STATUS_UNVERSIONED)
8331 		return NULL;
8332 
8333 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8334 	if (ie == NULL)
8335 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8336 
8337 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
8338 	    relpath)== -1)
8339 		return got_error_from_errno("asprintf");
8340 
8341 	switch (status) {
8342 	case GOT_STATUS_ADD:
8343 	case GOT_STATUS_MODIFY:
8344 		/* XXX could sb.st_mode be passed in by our caller? */
8345 		if (lstat(ondisk_path, &sb) == -1) {
8346 			err = got_error_from_errno2("lstat", ondisk_path);
8347 			break;
8348 		}
8349 		if (a->patch_cb) {
8350 			if (status == GOT_STATUS_ADD) {
8351 				int choice = GOT_PATCH_CHOICE_NONE;
8352 				err = (*a->patch_cb)(&choice, a->patch_arg,
8353 				    status, ie->path, NULL, 1, 1);
8354 				if (err)
8355 					break;
8356 				if (choice != GOT_PATCH_CHOICE_YES)
8357 					break;
8358 			} else {
8359 				err = create_patched_content(&path_content, 0,
8360 				    staged_blob_id ? staged_blob_id : blob_id,
8361 				    ondisk_path, dirfd, de_name, ie->path,
8362 				    a->repo, a->patch_cb, a->patch_arg);
8363 				if (err || path_content == NULL)
8364 					break;
8365 			}
8366 		}
8367 		err = got_object_blob_create(&new_staged_blob_id,
8368 		    path_content ? path_content : ondisk_path, a->repo);
8369 		if (err)
8370 			break;
8371 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
8372 		    SHA1_DIGEST_LENGTH);
8373 		if (status == GOT_STATUS_ADD || staged_status == GOT_STATUS_ADD)
8374 			stage = GOT_FILEIDX_STAGE_ADD;
8375 		else
8376 			stage = GOT_FILEIDX_STAGE_MODIFY;
8377 		got_fileindex_entry_stage_set(ie, stage);
8378 		if (S_ISLNK(sb.st_mode)) {
8379 			int is_bad_symlink = 0;
8380 			if (!a->allow_bad_symlinks) {
8381 				char target_path[PATH_MAX];
8382 				ssize_t target_len;
8383 				target_len = readlink(ondisk_path, target_path,
8384 				    sizeof(target_path));
8385 				if (target_len == -1) {
8386 					err = got_error_from_errno2("readlink",
8387 					    ondisk_path);
8388 					break;
8389 				}
8390 				err = is_bad_symlink_target(&is_bad_symlink,
8391 				    target_path, target_len, ondisk_path,
8392 				    a->worktree->root_path);
8393 				if (err)
8394 					break;
8395 				if (is_bad_symlink) {
8396 					err = got_error_path(ondisk_path,
8397 					    GOT_ERR_BAD_SYMLINK);
8398 					break;
8399 				}
8400 			}
8401 			if (is_bad_symlink)
8402 				got_fileindex_entry_staged_filetype_set(ie,
8403 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
8404 			else
8405 				got_fileindex_entry_staged_filetype_set(ie,
8406 				    GOT_FILEIDX_MODE_SYMLINK);
8407 		} else {
8408 			got_fileindex_entry_staged_filetype_set(ie,
8409 			    GOT_FILEIDX_MODE_REGULAR_FILE);
8410 		}
8411 		a->staged_something = 1;
8412 		if (a->status_cb == NULL)
8413 			break;
8414 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
8415 		    get_staged_status(ie), relpath, blob_id,
8416 		    new_staged_blob_id, NULL, dirfd, de_name);
8417 		if (err)
8418 			break;
8419 		/*
8420 		 * When staging the reverse of the staged diff,
8421 		 * implicitly unstage the file.
8422 		 */
8423 		if (memcmp(ie->staged_blob_sha1, ie->blob_sha1,
8424 		    sizeof(ie->blob_sha1)) == 0) {
8425 			got_fileindex_entry_stage_set(ie,
8426 			    GOT_FILEIDX_STAGE_NONE);
8427 		}
8428 		break;
8429 	case GOT_STATUS_DELETE:
8430 		if (staged_status == GOT_STATUS_DELETE)
8431 			break;
8432 		if (a->patch_cb) {
8433 			int choice = GOT_PATCH_CHOICE_NONE;
8434 			err = (*a->patch_cb)(&choice, a->patch_arg, status,
8435 			    ie->path, NULL, 1, 1);
8436 			if (err)
8437 				break;
8438 			if (choice == GOT_PATCH_CHOICE_NO)
8439 				break;
8440 			if (choice != GOT_PATCH_CHOICE_YES) {
8441 				err = got_error(GOT_ERR_PATCH_CHOICE);
8442 				break;
8443 			}
8444 		}
8445 		stage = GOT_FILEIDX_STAGE_DELETE;
8446 		got_fileindex_entry_stage_set(ie, stage);
8447 		a->staged_something = 1;
8448 		if (a->status_cb == NULL)
8449 			break;
8450 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
8451 		    get_staged_status(ie), relpath, NULL, NULL, NULL, dirfd,
8452 		    de_name);
8453 		break;
8454 	case GOT_STATUS_NO_CHANGE:
8455 		break;
8456 	case GOT_STATUS_CONFLICT:
8457 		err = got_error_path(relpath, GOT_ERR_STAGE_CONFLICT);
8458 		break;
8459 	case GOT_STATUS_NONEXISTENT:
8460 		err = got_error_set_errno(ENOENT, relpath);
8461 		break;
8462 	default:
8463 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
8464 		break;
8465 	}
8466 
8467 	if (path_content && unlink(path_content) == -1 && err == NULL)
8468 		err = got_error_from_errno2("unlink", path_content);
8469 	free(path_content);
8470 	free(ondisk_path);
8471 	free(new_staged_blob_id);
8472 	return err;
8473 }
8474 
8475 const struct got_error *
8476 got_worktree_stage(struct got_worktree *worktree,
8477     struct got_pathlist_head *paths,
8478     got_worktree_status_cb status_cb, void *status_arg,
8479     got_worktree_patch_cb patch_cb, void *patch_arg,
8480     int allow_bad_symlinks, struct got_repository *repo)
8481 {
8482 	const struct got_error *err = NULL, *sync_err, *unlockerr;
8483 	struct got_pathlist_entry *pe;
8484 	struct got_fileindex *fileindex = NULL;
8485 	char *fileindex_path = NULL;
8486 	struct got_reference *head_ref = NULL;
8487 	struct got_object_id *head_commit_id = NULL;
8488 	struct check_stage_ok_arg oka;
8489 	struct stage_path_arg spa;
8490 
8491 	err = lock_worktree(worktree, LOCK_EX);
8492 	if (err)
8493 		return err;
8494 
8495 	err = got_ref_open(&head_ref, repo,
8496 	    got_worktree_get_head_ref_name(worktree), 0);
8497 	if (err)
8498 		goto done;
8499 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
8500 	if (err)
8501 		goto done;
8502 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
8503 	if (err)
8504 		goto done;
8505 
8506 	/* Check pre-conditions before staging anything. */
8507 	oka.head_commit_id = head_commit_id;
8508 	oka.worktree = worktree;
8509 	oka.fileindex = fileindex;
8510 	oka.repo = repo;
8511 	oka.have_changes = 0;
8512 	TAILQ_FOREACH(pe, paths, entry) {
8513 		err = worktree_status(worktree, pe->path, fileindex, repo,
8514 		    check_stage_ok, &oka, NULL, NULL, 1, 0);
8515 		if (err)
8516 			goto done;
8517 	}
8518 	if (!oka.have_changes) {
8519 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
8520 		goto done;
8521 	}
8522 
8523 	spa.worktree = worktree;
8524 	spa.fileindex = fileindex;
8525 	spa.repo = repo;
8526 	spa.patch_cb = patch_cb;
8527 	spa.patch_arg = patch_arg;
8528 	spa.status_cb = status_cb;
8529 	spa.status_arg = status_arg;
8530 	spa.staged_something = 0;
8531 	spa.allow_bad_symlinks = allow_bad_symlinks;
8532 	TAILQ_FOREACH(pe, paths, entry) {
8533 		err = worktree_status(worktree, pe->path, fileindex, repo,
8534 		    stage_path, &spa, NULL, NULL, 1, 0);
8535 		if (err)
8536 			goto done;
8537 	}
8538 	if (!spa.staged_something) {
8539 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
8540 		goto done;
8541 	}
8542 
8543 	sync_err = sync_fileindex(fileindex, fileindex_path);
8544 	if (sync_err && err == NULL)
8545 		err = sync_err;
8546 done:
8547 	if (head_ref)
8548 		got_ref_close(head_ref);
8549 	free(head_commit_id);
8550 	free(fileindex_path);
8551 	if (fileindex)
8552 		got_fileindex_free(fileindex);
8553 	unlockerr = lock_worktree(worktree, LOCK_SH);
8554 	if (unlockerr && err == NULL)
8555 		err = unlockerr;
8556 	return err;
8557 }
8558 
8559 struct unstage_path_arg {
8560 	struct got_worktree *worktree;
8561 	struct got_fileindex *fileindex;
8562 	struct got_repository *repo;
8563 	got_worktree_checkout_cb progress_cb;
8564 	void *progress_arg;
8565 	got_worktree_patch_cb patch_cb;
8566 	void *patch_arg;
8567 };
8568 
8569 static const struct got_error *
8570 create_unstaged_content(char **path_unstaged_content,
8571     char **path_new_staged_content, struct got_object_id *blob_id,
8572     struct got_object_id *staged_blob_id, const char *relpath,
8573     struct got_repository *repo,
8574     got_worktree_patch_cb patch_cb, void *patch_arg)
8575 {
8576 	const struct got_error *err, *free_err;
8577 	struct got_blob_object *blob = NULL, *staged_blob = NULL;
8578 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL, *rejectfile = NULL;
8579 	char *path1 = NULL, *path2 = NULL, *label1 = NULL;
8580 	struct got_diffreg_result *diffreg_result = NULL;
8581 	int line_cur1 = 1, line_cur2 = 1, n = 0, nchunks_used = 0;
8582 	int have_content = 0, have_rejected_content = 0, i = 0, nchanges = 0;
8583 	int fd1 = -1, fd2 = -1;
8584 
8585 	*path_unstaged_content = NULL;
8586 	*path_new_staged_content = NULL;
8587 
8588 	err = got_object_id_str(&label1, blob_id);
8589 	if (err)
8590 		return err;
8591 
8592 	fd1 = got_opentempfd();
8593 	if (fd1 == -1) {
8594 		err = got_error_from_errno("got_opentempfd");
8595 		goto done;
8596 	}
8597 	fd2 = got_opentempfd();
8598 	if (fd2 == -1) {
8599 		err = got_error_from_errno("got_opentempfd");
8600 		goto done;
8601 	}
8602 
8603 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192, fd1);
8604 	if (err)
8605 		goto done;
8606 
8607 	err = got_opentemp_named(&path1, &f1, "got-unstage-blob-base", "");
8608 	if (err)
8609 		goto done;
8610 
8611 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
8612 	if (err)
8613 		goto done;
8614 
8615 	err = got_object_open_as_blob(&staged_blob, repo, staged_blob_id, 8192,
8616 	    fd2);
8617 	if (err)
8618 		goto done;
8619 
8620 	err = got_opentemp_named(&path2, &f2, "got-unstage-blob-staged", "");
8621 	if (err)
8622 		goto done;
8623 
8624 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f2, staged_blob);
8625 	if (err)
8626 		goto done;
8627 
8628 	err = got_diff_files(&diffreg_result, f1, 1, label1, f2, 1,
8629 	    path2, 3, 0, 1, NULL, GOT_DIFF_ALGORITHM_MYERS);
8630 	if (err)
8631 		goto done;
8632 
8633 	err = got_opentemp_named(path_unstaged_content, &outfile,
8634 	    "got-unstaged-content", "");
8635 	if (err)
8636 		goto done;
8637 	err = got_opentemp_named(path_new_staged_content, &rejectfile,
8638 	    "got-new-staged-content", "");
8639 	if (err)
8640 		goto done;
8641 
8642 	if (fseek(f1, 0L, SEEK_SET) == -1) {
8643 		err = got_ferror(f1, GOT_ERR_IO);
8644 		goto done;
8645 	}
8646 	if (fseek(f2, 0L, SEEK_SET) == -1) {
8647 		err = got_ferror(f2, GOT_ERR_IO);
8648 		goto done;
8649 	}
8650 	/* Count the number of actual changes in the diff result. */
8651 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
8652 		struct diff_chunk_context cc = {};
8653 		diff_chunk_context_load_change(&cc, &nchunks_used,
8654 		    diffreg_result->result, n, 0);
8655 		nchanges++;
8656 	}
8657 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
8658 		int choice;
8659 		err = apply_or_reject_change(&choice, &nchunks_used,
8660 		    diffreg_result->result, n, relpath, f1, f2,
8661 		    &line_cur1, &line_cur2,
8662 		    outfile, rejectfile, ++i, nchanges, patch_cb, patch_arg);
8663 		if (err)
8664 			goto done;
8665 		if (choice == GOT_PATCH_CHOICE_YES)
8666 			have_content = 1;
8667 		else
8668 			have_rejected_content = 1;
8669 		if (choice == GOT_PATCH_CHOICE_QUIT)
8670 			break;
8671 	}
8672 	if (have_content || have_rejected_content)
8673 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
8674 		    outfile, rejectfile);
8675 done:
8676 	free(label1);
8677 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
8678 		err = got_error_from_errno("close");
8679 	if (blob)
8680 		got_object_blob_close(blob);
8681 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
8682 		err = got_error_from_errno("close");
8683 	if (staged_blob)
8684 		got_object_blob_close(staged_blob);
8685 	free_err = got_diffreg_result_free(diffreg_result);
8686 	if (free_err && err == NULL)
8687 		err = free_err;
8688 	if (f1 && fclose(f1) == EOF && err == NULL)
8689 		err = got_error_from_errno2("fclose", path1);
8690 	if (f2 && fclose(f2) == EOF && err == NULL)
8691 		err = got_error_from_errno2("fclose", path2);
8692 	if (outfile && fclose(outfile) == EOF && err == NULL)
8693 		err = got_error_from_errno2("fclose", *path_unstaged_content);
8694 	if (rejectfile && fclose(rejectfile) == EOF && err == NULL)
8695 		err = got_error_from_errno2("fclose", *path_new_staged_content);
8696 	if (path1 && unlink(path1) == -1 && err == NULL)
8697 		err = got_error_from_errno2("unlink", path1);
8698 	if (path2 && unlink(path2) == -1 && err == NULL)
8699 		err = got_error_from_errno2("unlink", path2);
8700 	if (err || !have_content) {
8701 		if (*path_unstaged_content &&
8702 		    unlink(*path_unstaged_content) == -1 && err == NULL)
8703 			err = got_error_from_errno2("unlink",
8704 			    *path_unstaged_content);
8705 		free(*path_unstaged_content);
8706 		*path_unstaged_content = NULL;
8707 	}
8708 	if (err || !have_content || !have_rejected_content) {
8709 		if (*path_new_staged_content &&
8710 		    unlink(*path_new_staged_content) == -1 && err == NULL)
8711 			err = got_error_from_errno2("unlink",
8712 			    *path_new_staged_content);
8713 		free(*path_new_staged_content);
8714 		*path_new_staged_content = NULL;
8715 	}
8716 	free(path1);
8717 	free(path2);
8718 	return err;
8719 }
8720 
8721 static const struct got_error *
8722 unstage_hunks(struct got_object_id *staged_blob_id,
8723     struct got_blob_object *blob_base,
8724     struct got_object_id *blob_id, struct got_fileindex_entry *ie,
8725     const char *ondisk_path, const char *label_orig,
8726     struct got_worktree *worktree, struct got_repository *repo,
8727     got_worktree_patch_cb patch_cb, void *patch_arg,
8728     got_worktree_checkout_cb progress_cb, void *progress_arg)
8729 {
8730 	const struct got_error *err = NULL;
8731 	char *path_unstaged_content = NULL;
8732 	char *path_new_staged_content = NULL;
8733 	char *parent = NULL, *base_path = NULL;
8734 	char *blob_base_path = NULL;
8735 	struct got_object_id *new_staged_blob_id = NULL;
8736 	FILE *f = NULL, *f_base = NULL, *f_deriv2 = NULL;
8737 	struct stat sb;
8738 
8739 	err = create_unstaged_content(&path_unstaged_content,
8740 	    &path_new_staged_content, blob_id, staged_blob_id,
8741 	    ie->path, repo, patch_cb, patch_arg);
8742 	if (err)
8743 		return err;
8744 
8745 	if (path_unstaged_content == NULL)
8746 		return NULL;
8747 
8748 	if (path_new_staged_content) {
8749 		err = got_object_blob_create(&new_staged_blob_id,
8750 		    path_new_staged_content, repo);
8751 		if (err)
8752 			goto done;
8753 	}
8754 
8755 	f = fopen(path_unstaged_content, "re");
8756 	if (f == NULL) {
8757 		err = got_error_from_errno2("fopen",
8758 		    path_unstaged_content);
8759 		goto done;
8760 	}
8761 	if (fstat(fileno(f), &sb) == -1) {
8762 		err = got_error_from_errno2("fstat", path_unstaged_content);
8763 		goto done;
8764 	}
8765 	if (got_fileindex_entry_staged_filetype_get(ie) ==
8766 	    GOT_FILEIDX_MODE_SYMLINK && sb.st_size < PATH_MAX) {
8767 		char link_target[PATH_MAX];
8768 		size_t r;
8769 		r = fread(link_target, 1, sizeof(link_target), f);
8770 		if (r == 0 && ferror(f)) {
8771 			err = got_error_from_errno("fread");
8772 			goto done;
8773 		}
8774 		if (r >= sizeof(link_target)) { /* should not happen */
8775 			err = got_error(GOT_ERR_NO_SPACE);
8776 			goto done;
8777 		}
8778 		link_target[r] = '\0';
8779 		err = merge_symlink(worktree, blob_base,
8780 		    ondisk_path, ie->path, label_orig, link_target,
8781 		    worktree->base_commit_id, repo, progress_cb,
8782 		    progress_arg);
8783 	} else {
8784 		int local_changes_subsumed;
8785 
8786 		err = got_path_dirname(&parent, ondisk_path);
8787 		if (err)
8788 			return err;
8789 
8790 		if (asprintf(&base_path, "%s/got-unstage-blob-orig",
8791 		    parent) == -1) {
8792 			err = got_error_from_errno("asprintf");
8793 			base_path = NULL;
8794 			goto done;
8795 		}
8796 
8797 		err = got_opentemp_named(&blob_base_path, &f_base,
8798 		    base_path, "");
8799 		if (err)
8800 			goto done;
8801 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_base,
8802 		    blob_base);
8803 		if (err)
8804 			goto done;
8805 
8806 		/*
8807 		 * In order the run a 3-way merge with a symlink we copy the symlink's
8808 		 * target path into a temporary file and use that file with diff3.
8809 		 */
8810 		if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
8811 			err = dump_symlink_target_path_to_file(&f_deriv2,
8812 			    ondisk_path);
8813 			if (err)
8814 				goto done;
8815 		} else {
8816 			int fd;
8817 			fd = open(ondisk_path,
8818 			    O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
8819 			if (fd == -1) {
8820 				err = got_error_from_errno2("open", ondisk_path);
8821 				goto done;
8822 			}
8823 			f_deriv2 = fdopen(fd, "r");
8824 			if (f_deriv2 == NULL) {
8825 				err = got_error_from_errno2("fdopen", ondisk_path);
8826 				close(fd);
8827 				goto done;
8828 			}
8829 		}
8830 
8831 		err = merge_file(&local_changes_subsumed, worktree,
8832 		    f_base, f, f_deriv2, ondisk_path, ie->path,
8833 		    got_fileindex_perms_to_st(ie),
8834 		    label_orig, "unstaged", NULL, GOT_DIFF_ALGORITHM_MYERS,
8835 		    repo, progress_cb, progress_arg);
8836 	}
8837 	if (err)
8838 		goto done;
8839 
8840 	if (new_staged_blob_id) {
8841 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
8842 		    SHA1_DIGEST_LENGTH);
8843 	} else {
8844 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
8845 		got_fileindex_entry_staged_filetype_set(ie, 0);
8846 	}
8847 done:
8848 	free(new_staged_blob_id);
8849 	if (path_unstaged_content &&
8850 	    unlink(path_unstaged_content) == -1 && err == NULL)
8851 		err = got_error_from_errno2("unlink", path_unstaged_content);
8852 	if (path_new_staged_content &&
8853 	    unlink(path_new_staged_content) == -1 && err == NULL)
8854 		err = got_error_from_errno2("unlink", path_new_staged_content);
8855 	if (blob_base_path && unlink(blob_base_path) == -1 && err == NULL)
8856 		err = got_error_from_errno2("unlink", blob_base_path);
8857 	if (f_base && fclose(f_base) == EOF && err == NULL)
8858 		err = got_error_from_errno2("fclose", path_unstaged_content);
8859 	if (f && fclose(f) == EOF && err == NULL)
8860 		err = got_error_from_errno2("fclose", path_unstaged_content);
8861 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
8862 		err = got_error_from_errno2("fclose", ondisk_path);
8863 	free(path_unstaged_content);
8864 	free(path_new_staged_content);
8865 	free(blob_base_path);
8866 	free(parent);
8867 	free(base_path);
8868 	return err;
8869 }
8870 
8871 static const struct got_error *
8872 unstage_path(void *arg, unsigned char status,
8873     unsigned char staged_status, const char *relpath,
8874     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
8875     struct got_object_id *commit_id, int dirfd, const char *de_name)
8876 {
8877 	const struct got_error *err = NULL;
8878 	struct unstage_path_arg *a = arg;
8879 	struct got_fileindex_entry *ie;
8880 	struct got_blob_object *blob_base = NULL, *blob_staged = NULL;
8881 	char *ondisk_path = NULL;
8882 	char *id_str = NULL, *label_orig = NULL;
8883 	int local_changes_subsumed;
8884 	struct stat sb;
8885 	int fd1 = -1, fd2 = -1;
8886 
8887 	if (staged_status != GOT_STATUS_ADD &&
8888 	    staged_status != GOT_STATUS_MODIFY &&
8889 	    staged_status != GOT_STATUS_DELETE)
8890 		return NULL;
8891 
8892 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
8893 	if (ie == NULL)
8894 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
8895 
8896 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, relpath)
8897 	    == -1)
8898 		return got_error_from_errno("asprintf");
8899 
8900 	err = got_object_id_str(&id_str,
8901 	    commit_id ? commit_id : a->worktree->base_commit_id);
8902 	if (err)
8903 		goto done;
8904 	if (asprintf(&label_orig, "%s: commit %s", GOT_MERGE_LABEL_BASE,
8905 	    id_str) == -1) {
8906 		err = got_error_from_errno("asprintf");
8907 		goto done;
8908 	}
8909 
8910 	fd1 = got_opentempfd();
8911 	if (fd1 == -1) {
8912 		err = got_error_from_errno("got_opentempfd");
8913 		goto done;
8914 	}
8915 	fd2 = got_opentempfd();
8916 	if (fd2 == -1) {
8917 		err = got_error_from_errno("got_opentempfd");
8918 		goto done;
8919 	}
8920 
8921 	switch (staged_status) {
8922 	case GOT_STATUS_MODIFY:
8923 		err = got_object_open_as_blob(&blob_base, a->repo,
8924 		    blob_id, 8192, fd1);
8925 		if (err)
8926 			break;
8927 		/* fall through */
8928 	case GOT_STATUS_ADD:
8929 		if (a->patch_cb) {
8930 			if (staged_status == GOT_STATUS_ADD) {
8931 				int choice = GOT_PATCH_CHOICE_NONE;
8932 				err = (*a->patch_cb)(&choice, a->patch_arg,
8933 				    staged_status, ie->path, NULL, 1, 1);
8934 				if (err)
8935 					break;
8936 				if (choice != GOT_PATCH_CHOICE_YES)
8937 					break;
8938 			} else {
8939 				err = unstage_hunks(staged_blob_id,
8940 				    blob_base, blob_id, ie, ondisk_path,
8941 				    label_orig, a->worktree, a->repo,
8942 				    a->patch_cb, a->patch_arg,
8943 				    a->progress_cb, a->progress_arg);
8944 				break; /* Done with this file. */
8945 			}
8946 		}
8947 		err = got_object_open_as_blob(&blob_staged, a->repo,
8948 		    staged_blob_id, 8192, fd2);
8949 		if (err)
8950 			break;
8951 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
8952 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
8953 		case GOT_FILEIDX_MODE_REGULAR_FILE:
8954 			err = merge_blob(&local_changes_subsumed, a->worktree,
8955 			    blob_base, ondisk_path, relpath,
8956 			    got_fileindex_perms_to_st(ie), label_orig,
8957 			    blob_staged, commit_id ? commit_id :
8958 			    a->worktree->base_commit_id, a->repo,
8959 			    a->progress_cb, a->progress_arg);
8960 			break;
8961 		case GOT_FILEIDX_MODE_SYMLINK:
8962 			if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
8963 				char *staged_target;
8964 				err = got_object_blob_read_to_str(
8965 				    &staged_target, blob_staged);
8966 				if (err)
8967 					goto done;
8968 				err = merge_symlink(a->worktree, blob_base,
8969 				    ondisk_path, relpath, label_orig,
8970 				    staged_target, commit_id ? commit_id :
8971 				    a->worktree->base_commit_id,
8972 				    a->repo, a->progress_cb, a->progress_arg);
8973 				free(staged_target);
8974 			} else {
8975 				err = merge_blob(&local_changes_subsumed,
8976 				    a->worktree, blob_base, ondisk_path,
8977 				    relpath, got_fileindex_perms_to_st(ie),
8978 				    label_orig, blob_staged,
8979 				    commit_id ? commit_id :
8980 				    a->worktree->base_commit_id, a->repo,
8981 				    a->progress_cb, a->progress_arg);
8982 			}
8983 			break;
8984 		default:
8985 			err = got_error_path(relpath, GOT_ERR_BAD_FILETYPE);
8986 			break;
8987 		}
8988 		if (err == NULL) {
8989 			got_fileindex_entry_stage_set(ie,
8990 			    GOT_FILEIDX_STAGE_NONE);
8991 			got_fileindex_entry_staged_filetype_set(ie, 0);
8992 		}
8993 		break;
8994 	case GOT_STATUS_DELETE:
8995 		if (a->patch_cb) {
8996 			int choice = GOT_PATCH_CHOICE_NONE;
8997 			err = (*a->patch_cb)(&choice, a->patch_arg,
8998 			    staged_status, ie->path, NULL, 1, 1);
8999 			if (err)
9000 				break;
9001 			if (choice == GOT_PATCH_CHOICE_NO)
9002 				break;
9003 			if (choice != GOT_PATCH_CHOICE_YES) {
9004 				err = got_error(GOT_ERR_PATCH_CHOICE);
9005 				break;
9006 			}
9007 		}
9008 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
9009 		got_fileindex_entry_staged_filetype_set(ie, 0);
9010 		err = get_file_status(&status, &sb, ie, ondisk_path,
9011 		    dirfd, de_name, a->repo);
9012 		if (err)
9013 			break;
9014 		err = (*a->progress_cb)(a->progress_arg, status, relpath);
9015 		break;
9016 	}
9017 done:
9018 	free(ondisk_path);
9019 	if (fd1 != -1 && close(fd1) == -1 && err == NULL)
9020 		err = got_error_from_errno("close");
9021 	if (blob_base)
9022 		got_object_blob_close(blob_base);
9023 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
9024 		err = got_error_from_errno("close");
9025 	if (blob_staged)
9026 		got_object_blob_close(blob_staged);
9027 	free(id_str);
9028 	free(label_orig);
9029 	return err;
9030 }
9031 
9032 const struct got_error *
9033 got_worktree_unstage(struct got_worktree *worktree,
9034     struct got_pathlist_head *paths,
9035     got_worktree_checkout_cb progress_cb, void *progress_arg,
9036     got_worktree_patch_cb patch_cb, void *patch_arg,
9037     struct got_repository *repo)
9038 {
9039 	const struct got_error *err = NULL, *sync_err, *unlockerr;
9040 	struct got_pathlist_entry *pe;
9041 	struct got_fileindex *fileindex = NULL;
9042 	char *fileindex_path = NULL;
9043 	struct unstage_path_arg upa;
9044 
9045 	err = lock_worktree(worktree, LOCK_EX);
9046 	if (err)
9047 		return err;
9048 
9049 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
9050 	if (err)
9051 		goto done;
9052 
9053 	upa.worktree = worktree;
9054 	upa.fileindex = fileindex;
9055 	upa.repo = repo;
9056 	upa.progress_cb = progress_cb;
9057 	upa.progress_arg = progress_arg;
9058 	upa.patch_cb = patch_cb;
9059 	upa.patch_arg = patch_arg;
9060 	TAILQ_FOREACH(pe, paths, entry) {
9061 		err = worktree_status(worktree, pe->path, fileindex, repo,
9062 		    unstage_path, &upa, NULL, NULL, 1, 0);
9063 		if (err)
9064 			goto done;
9065 	}
9066 
9067 	sync_err = sync_fileindex(fileindex, fileindex_path);
9068 	if (sync_err && err == NULL)
9069 		err = sync_err;
9070 done:
9071 	free(fileindex_path);
9072 	if (fileindex)
9073 		got_fileindex_free(fileindex);
9074 	unlockerr = lock_worktree(worktree, LOCK_SH);
9075 	if (unlockerr && err == NULL)
9076 		err = unlockerr;
9077 	return err;
9078 }
9079 
9080 struct report_file_info_arg {
9081 	struct got_worktree *worktree;
9082 	got_worktree_path_info_cb info_cb;
9083 	void *info_arg;
9084 	struct got_pathlist_head *paths;
9085 	got_cancel_cb cancel_cb;
9086 	void *cancel_arg;
9087 };
9088 
9089 static const struct got_error *
9090 report_file_info(void *arg, struct got_fileindex_entry *ie)
9091 {
9092 	struct report_file_info_arg *a = arg;
9093 	struct got_pathlist_entry *pe;
9094 	struct got_object_id blob_id, staged_blob_id, commit_id;
9095 	struct got_object_id *blob_idp = NULL, *staged_blob_idp = NULL;
9096 	struct got_object_id *commit_idp = NULL;
9097 	int stage;
9098 
9099 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
9100 		return got_error(GOT_ERR_CANCELLED);
9101 
9102 	TAILQ_FOREACH(pe, a->paths, entry) {
9103 		if (pe->path_len == 0 || strcmp(pe->path, ie->path) == 0 ||
9104 		    got_path_is_child(ie->path, pe->path, pe->path_len))
9105 			break;
9106 	}
9107 	if (pe == NULL) /* not found */
9108 		return NULL;
9109 
9110 	if (got_fileindex_entry_has_blob(ie)) {
9111 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
9112 		blob_idp = &blob_id;
9113 	}
9114 	stage = got_fileindex_entry_stage_get(ie);
9115 	if (stage == GOT_FILEIDX_STAGE_MODIFY ||
9116 	    stage == GOT_FILEIDX_STAGE_ADD) {
9117 		memcpy(staged_blob_id.sha1, ie->staged_blob_sha1,
9118 		    SHA1_DIGEST_LENGTH);
9119 		staged_blob_idp = &staged_blob_id;
9120 	}
9121 
9122 	if (got_fileindex_entry_has_commit(ie)) {
9123 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
9124 		commit_idp = &commit_id;
9125 	}
9126 
9127 	return a->info_cb(a->info_arg, ie->path, got_fileindex_perms_to_st(ie),
9128 	    (time_t)ie->mtime_sec, blob_idp, staged_blob_idp, commit_idp);
9129 }
9130 
9131 const struct got_error *
9132 got_worktree_path_info(struct got_worktree *worktree,
9133     struct got_pathlist_head *paths,
9134     got_worktree_path_info_cb info_cb, void *info_arg,
9135     got_cancel_cb cancel_cb, void *cancel_arg)
9136 
9137 {
9138 	const struct got_error *err = NULL, *unlockerr;
9139 	struct got_fileindex *fileindex = NULL;
9140 	char *fileindex_path = NULL;
9141 	struct report_file_info_arg arg;
9142 
9143 	err = lock_worktree(worktree, LOCK_SH);
9144 	if (err)
9145 		return err;
9146 
9147 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
9148 	if (err)
9149 		goto done;
9150 
9151 	arg.worktree = worktree;
9152 	arg.info_cb = info_cb;
9153 	arg.info_arg = info_arg;
9154 	arg.paths = paths;
9155 	arg.cancel_cb = cancel_cb;
9156 	arg.cancel_arg = cancel_arg;
9157 	err = got_fileindex_for_each_entry_safe(fileindex, report_file_info,
9158 	    &arg);
9159 done:
9160 	free(fileindex_path);
9161 	if (fileindex)
9162 		got_fileindex_free(fileindex);
9163 	unlockerr = lock_worktree(worktree, LOCK_UN);
9164 	if (unlockerr && err == NULL)
9165 		err = unlockerr;
9166 	return err;
9167 }
9168 
9169 static const struct got_error *
9170 patch_check_path(const char *p, char **path, unsigned char *status,
9171     unsigned char *staged_status, struct got_fileindex *fileindex,
9172     struct got_worktree *worktree, struct got_repository *repo)
9173 {
9174 	const struct got_error *err;
9175 	struct got_fileindex_entry *ie;
9176 	struct stat sb;
9177 	char *ondisk_path = NULL;
9178 
9179 	err = got_worktree_resolve_path(path, worktree, p);
9180 	if (err)
9181 		return err;
9182 
9183 	if (asprintf(&ondisk_path, "%s%s%s", worktree->root_path,
9184 	    *path[0] ? "/" : "", *path) == -1)
9185 		return got_error_from_errno("asprintf");
9186 
9187 	ie = got_fileindex_entry_get(fileindex, *path, strlen(*path));
9188 	if (ie) {
9189 		*staged_status = get_staged_status(ie);
9190 		err = get_file_status(status, &sb, ie, ondisk_path, -1, NULL,
9191 		    repo);
9192 		if (err)
9193 			goto done;
9194 	} else {
9195 		*staged_status = GOT_STATUS_NO_CHANGE;
9196 		*status = GOT_STATUS_UNVERSIONED;
9197 		if (lstat(ondisk_path, &sb) == -1) {
9198 			if (errno != ENOENT) {
9199 				err = got_error_from_errno2("lstat",
9200 				    ondisk_path);
9201 				goto done;
9202 			}
9203 			*status = GOT_STATUS_NONEXISTENT;
9204 		}
9205 	}
9206 
9207 done:
9208 	free(ondisk_path);
9209 	return err;
9210 }
9211 
9212 static const struct got_error *
9213 patch_can_rm(const char *path, unsigned char status,
9214     unsigned char staged_status)
9215 {
9216 	if (status == GOT_STATUS_NONEXISTENT)
9217 		return got_error_set_errno(ENOENT, path);
9218 	if (status != GOT_STATUS_NO_CHANGE &&
9219 	    status != GOT_STATUS_ADD &&
9220 	    status != GOT_STATUS_MODIFY &&
9221 	    status != GOT_STATUS_MODE_CHANGE)
9222 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9223 	if (staged_status == GOT_STATUS_DELETE)
9224 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9225 	return NULL;
9226 }
9227 
9228 static const struct got_error *
9229 patch_can_add(const char *path, unsigned char status)
9230 {
9231 	if (status != GOT_STATUS_NONEXISTENT)
9232 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9233 	return NULL;
9234 }
9235 
9236 static const struct got_error *
9237 patch_can_edit(const char *path, unsigned char status,
9238     unsigned char staged_status)
9239 {
9240 	if (status == GOT_STATUS_NONEXISTENT)
9241 		return got_error_set_errno(ENOENT, path);
9242 	if (status != GOT_STATUS_NO_CHANGE &&
9243 	    status != GOT_STATUS_ADD &&
9244 	    status != GOT_STATUS_MODIFY)
9245 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9246 	if (staged_status == GOT_STATUS_DELETE)
9247 		return got_error_path(path, GOT_ERR_FILE_STATUS);
9248 	return NULL;
9249 }
9250 
9251 const struct got_error *
9252 got_worktree_patch_prepare(struct got_fileindex **fileindex,
9253     char **fileindex_path, struct got_worktree *worktree)
9254 {
9255 	return open_fileindex(fileindex, fileindex_path, worktree);
9256 }
9257 
9258 const struct got_error *
9259 got_worktree_patch_check_path(const char *old, const char *new,
9260     char **oldpath, char **newpath, struct got_worktree *worktree,
9261     struct got_repository *repo, struct got_fileindex *fileindex)
9262 {
9263 	const struct got_error *err = NULL;
9264 	int file_renamed = 0;
9265 	unsigned char status_old, staged_status_old;
9266 	unsigned char status_new, staged_status_new;
9267 
9268 	*oldpath = NULL;
9269 	*newpath = NULL;
9270 
9271 	err = patch_check_path(old != NULL ? old : new, oldpath,
9272 	    &status_old, &staged_status_old, fileindex, worktree, repo);
9273 	if (err)
9274 		goto done;
9275 
9276 	err = patch_check_path(new != NULL ? new : old, newpath,
9277 	    &status_new, &staged_status_new, fileindex, worktree, repo);
9278 	if (err)
9279 		goto done;
9280 
9281 	if (old != NULL && new != NULL && strcmp(old, new) != 0)
9282 		file_renamed = 1;
9283 
9284 	if (old != NULL && new == NULL)
9285 		err = patch_can_rm(*oldpath, status_old, staged_status_old);
9286 	else if (file_renamed) {
9287 		err = patch_can_rm(*oldpath, status_old, staged_status_old);
9288 		if (err == NULL)
9289 			err = patch_can_add(*newpath, status_new);
9290 	} else if (old == NULL)
9291 		err = patch_can_add(*newpath, status_new);
9292 	else
9293 		err = patch_can_edit(*newpath, status_new, staged_status_new);
9294 
9295 done:
9296 	if (err) {
9297 		free(*oldpath);
9298 		*oldpath = NULL;
9299 		free(*newpath);
9300 		*newpath = NULL;
9301 	}
9302 	return err;
9303 }
9304 
9305 const struct got_error *
9306 got_worktree_patch_schedule_add(const char *path, struct got_repository *repo,
9307     struct got_worktree *worktree, struct got_fileindex *fileindex,
9308     got_worktree_checkout_cb progress_cb, void *progress_arg)
9309 {
9310 	struct schedule_addition_args saa;
9311 
9312 	memset(&saa, 0, sizeof(saa));
9313 	saa.worktree = worktree;
9314 	saa.fileindex = fileindex;
9315 	saa.progress_cb = progress_cb;
9316 	saa.progress_arg = progress_arg;
9317 	saa.repo = repo;
9318 
9319 	return worktree_status(worktree, path, fileindex, repo,
9320 	    schedule_addition, &saa, NULL, NULL, 1, 0);
9321 }
9322 
9323 const struct got_error *
9324 got_worktree_patch_schedule_rm(const char *path, struct got_repository *repo,
9325     struct got_worktree *worktree, struct got_fileindex *fileindex,
9326     got_worktree_delete_cb progress_cb, void *progress_arg)
9327 {
9328 	struct schedule_deletion_args sda;
9329 
9330 	memset(&sda, 0, sizeof(sda));
9331 	sda.worktree = worktree;
9332 	sda.fileindex = fileindex;
9333 	sda.progress_cb = progress_cb;
9334 	sda.progress_arg = progress_arg;
9335 	sda.repo = repo;
9336 	sda.delete_local_mods = 0;
9337 	sda.keep_on_disk = 0;
9338 	sda.ignore_missing_paths = 0;
9339 	sda.status_codes = NULL;
9340 
9341 	return worktree_status(worktree, path, fileindex, repo,
9342 	    schedule_for_deletion, &sda, NULL, NULL, 1, 1);
9343 }
9344 
9345 const struct got_error *
9346 got_worktree_patch_complete(struct got_fileindex *fileindex,
9347     const char *fileindex_path)
9348 {
9349 	const struct got_error *err = NULL;
9350 
9351 	err = sync_fileindex(fileindex, fileindex_path);
9352 	got_fileindex_free(fileindex);
9353 
9354 	return err;
9355 }