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