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