1 /*
2  * Copyright (c) 2018, 2019 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/limits.h>
19 #include <sys/queue.h>
20 #include <sys/tree.h>
21 
22 #include <dirent.h>
23 #include <stddef.h>
24 #include <string.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <fcntl.h>
28 #include <errno.h>
29 #include <unistd.h>
30 #include <sha1.h>
31 #include <zlib.h>
32 #include <fnmatch.h>
33 #include <libgen.h>
34 #include <uuid.h>
35 #include <util.h>
36 
37 #include "got_error.h"
38 #include "got_repository.h"
39 #include "got_reference.h"
40 #include "got_object.h"
41 #include "got_path.h"
42 #include "got_worktree.h"
43 #include "got_opentemp.h"
44 #include "got_diff.h"
45 
46 #include "got_lib_worktree.h"
47 #include "got_lib_sha1.h"
48 #include "got_lib_fileindex.h"
49 #include "got_lib_inflate.h"
50 #include "got_lib_delta.h"
51 #include "got_lib_object.h"
52 #include "got_lib_object_parse.h"
53 #include "got_lib_object_create.h"
54 #include "got_lib_object_idset.h"
55 #include "got_lib_diff.h"
56 
57 #ifndef MIN
58 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
59 #endif
60 
61 static const struct got_error *
62 create_meta_file(const char *path_got, const char *name, const char *content)
63 {
64 	const struct got_error *err = NULL;
65 	char *path;
66 
67 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
68 		return got_error_from_errno("asprintf");
69 
70 	err = got_path_create_file(path, content);
71 	free(path);
72 	return err;
73 }
74 
75 static const struct got_error *
76 update_meta_file(const char *path_got, const char *name, const char *content)
77 {
78 	const struct got_error *err = NULL;
79 	FILE *tmpfile = NULL;
80 	char *tmppath = NULL;
81 	char *path = NULL;
82 
83 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
84 		err = got_error_from_errno("asprintf");
85 		path = NULL;
86 		goto done;
87 	}
88 
89 	err = got_opentemp_named(&tmppath, &tmpfile, path);
90 	if (err)
91 		goto done;
92 
93 	if (content) {
94 		int len = fprintf(tmpfile, "%s\n", content);
95 		if (len != strlen(content) + 1) {
96 			err = got_error_from_errno2("fprintf", tmppath);
97 			goto done;
98 		}
99 	}
100 
101 	if (rename(tmppath, path) != 0) {
102 		err = got_error_from_errno3("rename", tmppath, path);
103 		unlink(tmppath);
104 		goto done;
105 	}
106 
107 done:
108 	if (fclose(tmpfile) != 0 && err == NULL)
109 		err = got_error_from_errno2("fclose", tmppath);
110 	free(tmppath);
111 	return err;
112 }
113 
114 static const struct got_error *
115 read_meta_file(char **content, const char *path_got, const char *name)
116 {
117 	const struct got_error *err = NULL;
118 	char *path;
119 	int fd = -1;
120 	ssize_t n;
121 	struct stat sb;
122 
123 	*content = NULL;
124 
125 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
126 		err = got_error_from_errno("asprintf");
127 		path = NULL;
128 		goto done;
129 	}
130 
131 	fd = open(path, O_RDONLY | O_NOFOLLOW);
132 	if (fd == -1) {
133 		if (errno == ENOENT)
134 			err = got_error(GOT_ERR_WORKTREE_META);
135 		else
136 			err = got_error_from_errno2("open", path);
137 		goto done;
138 	}
139 	if (flock(fd, LOCK_SH | LOCK_NB) == -1) {
140 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
141 		    : got_error_from_errno2("flock", path));
142 		goto done;
143 	}
144 
145 	if (lstat(path, &sb) != 0) {
146 		err = got_error_from_errno2("lstat", path);
147 		goto done;
148 	}
149 	*content = calloc(1, sb.st_size);
150 	if (*content == NULL) {
151 		err = got_error_from_errno("calloc");
152 		goto done;
153 	}
154 
155 	n = read(fd, *content, sb.st_size);
156 	if (n != sb.st_size) {
157 		err = (n == -1 ? got_error_from_errno2("read", path) :
158 		    got_error(GOT_ERR_WORKTREE_META));
159 		goto done;
160 	}
161 	if ((*content)[sb.st_size - 1] != '\n') {
162 		err = got_error(GOT_ERR_WORKTREE_META);
163 		goto done;
164 	}
165 	(*content)[sb.st_size - 1] = '\0';
166 
167 done:
168 	if (fd != -1 && close(fd) == -1 && err == NULL)
169 		err = got_error_from_errno2("close", path_got);
170 	free(path);
171 	if (err) {
172 		free(*content);
173 		*content = NULL;
174 	}
175 	return err;
176 }
177 
178 static const struct got_error *
179 write_head_ref(const char *path_got, struct got_reference *head_ref)
180 {
181 	const struct got_error *err = NULL;
182 	char *refstr = NULL;
183 
184 	if (got_ref_is_symbolic(head_ref)) {
185 		refstr = got_ref_to_str(head_ref);
186 		if (refstr == NULL)
187 			return got_error_from_errno("got_ref_to_str");
188 	} else {
189 		refstr = strdup(got_ref_get_name(head_ref));
190 		if (refstr == NULL)
191 			return got_error_from_errno("strdup");
192 	}
193 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
194 	free(refstr);
195 	return err;
196 }
197 
198 const struct got_error *
199 got_worktree_init(const char *path, struct got_reference *head_ref,
200     const char *prefix, struct got_repository *repo)
201 {
202 	const struct got_error *err = NULL;
203 	struct got_object_id *commit_id = NULL;
204 	uuid_t uuid;
205 	uint32_t uuid_status;
206 	int obj_type;
207 	char *path_got = NULL;
208 	char *formatstr = NULL;
209 	char *absprefix = NULL;
210 	char *basestr = NULL;
211 	char *uuidstr = NULL;
212 
213 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
214 		err = got_error(GOT_ERR_WORKTREE_REPO);
215 		goto done;
216 	}
217 
218 	err = got_ref_resolve(&commit_id, repo, head_ref);
219 	if (err)
220 		return err;
221 	err = got_object_get_type(&obj_type, repo, commit_id);
222 	if (err)
223 		return err;
224 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
225 		return got_error(GOT_ERR_OBJ_TYPE);
226 
227 	if (!got_path_is_absolute(prefix)) {
228 		if (asprintf(&absprefix, "/%s", prefix) == -1)
229 			return got_error_from_errno("asprintf");
230 	}
231 
232 	/* Create top-level directory (may already exist). */
233 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
234 		err = got_error_from_errno2("mkdir", path);
235 		goto done;
236 	}
237 
238 	/* Create .got directory (may already exist). */
239 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
240 		err = got_error_from_errno("asprintf");
241 		goto done;
242 	}
243 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
244 		err = got_error_from_errno2("mkdir", path_got);
245 		goto done;
246 	}
247 
248 	/* Create an empty lock file. */
249 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
250 	if (err)
251 		goto done;
252 
253 	/* Create an empty file index. */
254 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
255 	if (err)
256 		goto done;
257 
258 	/* Write the HEAD reference. */
259 	err = write_head_ref(path_got, head_ref);
260 	if (err)
261 		goto done;
262 
263 	/* Record our base commit. */
264 	err = got_object_id_str(&basestr, commit_id);
265 	if (err)
266 		goto done;
267 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
268 	if (err)
269 		goto done;
270 
271 	/* Store path to repository. */
272 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
273 	    got_repo_get_path(repo));
274 	if (err)
275 		goto done;
276 
277 	/* Store in-repository path prefix. */
278 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
279 	    absprefix ? absprefix : prefix);
280 	if (err)
281 		goto done;
282 
283 	/* Generate UUID. */
284 	uuid_create(&uuid, &uuid_status);
285 	if (uuid_status != uuid_s_ok) {
286 		err = got_error_uuid(uuid_status);
287 		goto done;
288 	}
289 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
290 	if (uuid_status != uuid_s_ok) {
291 		err = got_error_uuid(uuid_status);
292 		goto done;
293 	}
294 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
295 	if (err)
296 		goto done;
297 
298 	/* Stamp work tree with format file. */
299 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
300 		err = got_error_from_errno("asprintf");
301 		goto done;
302 	}
303 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
304 	if (err)
305 		goto done;
306 
307 done:
308 	free(commit_id);
309 	free(path_got);
310 	free(formatstr);
311 	free(absprefix);
312 	free(basestr);
313 	free(uuidstr);
314 	return err;
315 }
316 
317 static const struct got_error *
318 open_worktree(struct got_worktree **worktree, const char *path)
319 {
320 	const struct got_error *err = NULL;
321 	char *path_got;
322 	char *formatstr = NULL;
323 	char *uuidstr = NULL;
324 	char *path_lock = NULL;
325 	char *base_commit_id_str = NULL;
326 	int version, fd = -1;
327 	const char *errstr;
328 	struct got_repository *repo = NULL;
329 	uint32_t uuid_status;
330 
331 	*worktree = NULL;
332 
333 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
334 		err = got_error_from_errno("asprintf");
335 		path_got = NULL;
336 		goto done;
337 	}
338 
339 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
340 		err = got_error_from_errno("asprintf");
341 		path_lock = NULL;
342 		goto done;
343 	}
344 
345 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
346 	if (fd == -1) {
347 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
348 		    : got_error_from_errno2("open", path_lock));
349 		goto done;
350 	}
351 
352 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
353 	if (err)
354 		goto done;
355 
356 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
357 	if (errstr) {
358 		err = got_error(GOT_ERR_WORKTREE_META);
359 		goto done;
360 	}
361 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
362 		err = got_error(GOT_ERR_WORKTREE_VERS);
363 		goto done;
364 	}
365 
366 	*worktree = calloc(1, sizeof(**worktree));
367 	if (*worktree == NULL) {
368 		err = got_error_from_errno("calloc");
369 		goto done;
370 	}
371 	(*worktree)->lockfd = -1;
372 
373 	(*worktree)->root_path = strdup(path);
374 	if ((*worktree)->root_path == NULL) {
375 		err = got_error_from_errno("strdup");
376 		goto done;
377 	}
378 	err = read_meta_file(&(*worktree)->repo_path, path_got,
379 	    GOT_WORKTREE_REPOSITORY);
380 	if (err)
381 		goto done;
382 
383 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
384 	    GOT_WORKTREE_PATH_PREFIX);
385 	if (err)
386 		goto done;
387 
388 	err = read_meta_file(&base_commit_id_str, path_got,
389 	    GOT_WORKTREE_BASE_COMMIT);
390 	if (err)
391 		goto done;
392 
393 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
394 	if (err)
395 		goto done;
396 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
397 	if (uuid_status != uuid_s_ok) {
398 		err = got_error_uuid(uuid_status);
399 		goto done;
400 	}
401 
402 	err = got_repo_open(&repo, (*worktree)->repo_path);
403 	if (err)
404 		goto done;
405 
406 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
407 	    base_commit_id_str);
408 	if (err)
409 		goto done;
410 
411 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
412 	    GOT_WORKTREE_HEAD_REF);
413 done:
414 	if (repo)
415 		got_repo_close(repo);
416 	free(path_got);
417 	free(path_lock);
418 	free(base_commit_id_str);
419 	free(uuidstr);
420 	free(formatstr);
421 	if (err) {
422 		if (fd != -1)
423 			close(fd);
424 		if (*worktree != NULL)
425 			got_worktree_close(*worktree);
426 		*worktree = NULL;
427 	} else
428 		(*worktree)->lockfd = fd;
429 
430 	return err;
431 }
432 
433 const struct got_error *
434 got_worktree_open(struct got_worktree **worktree, const char *path)
435 {
436 	const struct got_error *err = NULL;
437 
438 	do {
439 		err = open_worktree(worktree, path);
440 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT))
441 			return err;
442 		if (*worktree)
443 			return NULL;
444 		path = dirname(path);
445 		if (path == NULL)
446 			return got_error_from_errno2("dirname", path);
447 	} while (!((path[0] == '.' || path[0] == '/') && path[1] == '\0'));
448 
449 	return got_error(GOT_ERR_NOT_WORKTREE);
450 }
451 
452 const struct got_error *
453 got_worktree_close(struct got_worktree *worktree)
454 {
455 	const struct got_error *err = NULL;
456 	free(worktree->root_path);
457 	free(worktree->repo_path);
458 	free(worktree->path_prefix);
459 	free(worktree->base_commit_id);
460 	free(worktree->head_ref_name);
461 	if (worktree->lockfd != -1)
462 		if (close(worktree->lockfd) != 0)
463 			err = got_error_from_errno2("close",
464 			    got_worktree_get_root_path(worktree));
465 	free(worktree);
466 	return err;
467 }
468 
469 const char *
470 got_worktree_get_root_path(struct got_worktree *worktree)
471 {
472 	return worktree->root_path;
473 }
474 
475 const char *
476 got_worktree_get_repo_path(struct got_worktree *worktree)
477 {
478 	return worktree->repo_path;
479 }
480 
481 const char *
482 got_worktree_get_path_prefix(struct got_worktree *worktree)
483 {
484 	return worktree->path_prefix;
485 }
486 
487 const struct got_error *
488 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
489     const char *path_prefix)
490 {
491 	char *absprefix = NULL;
492 
493 	if (!got_path_is_absolute(path_prefix)) {
494 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
495 			return got_error_from_errno("asprintf");
496 	}
497 	*match = (strcmp(absprefix ? absprefix : path_prefix,
498 	    worktree->path_prefix) == 0);
499 	free(absprefix);
500 	return NULL;
501 }
502 
503 const char *
504 got_worktree_get_head_ref_name(struct got_worktree *worktree)
505 {
506 	return worktree->head_ref_name;
507 }
508 
509 const struct got_error *
510 got_worktree_set_head_ref(struct got_worktree *worktree,
511     struct got_reference *head_ref)
512 {
513 	const struct got_error *err = NULL;
514 	char *path_got = NULL, *head_ref_name = NULL;
515 
516 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
517 	    GOT_WORKTREE_GOT_DIR) == -1) {
518 		err = got_error_from_errno("asprintf");
519 		path_got = NULL;
520 		goto done;
521 	}
522 
523 	head_ref_name = strdup(got_ref_get_name(head_ref));
524 	if (head_ref_name == NULL) {
525 		err = got_error_from_errno("strdup");
526 		goto done;
527 	}
528 
529 	err = write_head_ref(path_got, head_ref);
530 	if (err)
531 		goto done;
532 
533 	free(worktree->head_ref_name);
534 	worktree->head_ref_name = head_ref_name;
535 done:
536 	free(path_got);
537 	if (err)
538 		free(head_ref_name);
539 	return err;
540 }
541 
542 struct got_object_id *
543 got_worktree_get_base_commit_id(struct got_worktree *worktree)
544 {
545 	return worktree->base_commit_id;
546 }
547 
548 const struct got_error *
549 got_worktree_set_base_commit_id(struct got_worktree *worktree,
550     struct got_repository *repo, struct got_object_id *commit_id)
551 {
552 	const struct got_error *err;
553 	struct got_object *obj = NULL;
554 	char *id_str = NULL;
555 	char *path_got = NULL;
556 
557 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
558 	    GOT_WORKTREE_GOT_DIR) == -1) {
559 		err = got_error_from_errno("asprintf");
560 		path_got = NULL;
561 		goto done;
562 	}
563 
564 	err = got_object_open(&obj, repo, commit_id);
565 	if (err)
566 		return err;
567 
568 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
569 		err = got_error(GOT_ERR_OBJ_TYPE);
570 		goto done;
571 	}
572 
573 	/* Record our base commit. */
574 	err = got_object_id_str(&id_str, commit_id);
575 	if (err)
576 		goto done;
577 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
578 	if (err)
579 		goto done;
580 
581 	free(worktree->base_commit_id);
582 	worktree->base_commit_id = got_object_id_dup(commit_id);
583 	if (worktree->base_commit_id == NULL) {
584 		err = got_error_from_errno("got_object_id_dup");
585 		goto done;
586 	}
587 done:
588 	if (obj)
589 		got_object_close(obj);
590 	free(id_str);
591 	free(path_got);
592 	return err;
593 }
594 
595 static const struct got_error *
596 lock_worktree(struct got_worktree *worktree, int operation)
597 {
598 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
599 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
600 		    : got_error_from_errno2("flock",
601 		    got_worktree_get_root_path(worktree)));
602 	return NULL;
603 }
604 
605 static const struct got_error *
606 add_dir_on_disk(struct got_worktree *worktree, const char *path)
607 {
608 	const struct got_error *err = NULL;
609 	char *abspath;
610 
611 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
612 		return got_error_from_errno("asprintf");
613 
614 	err = got_path_mkdir(abspath);
615 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
616 		struct stat sb;
617 		err = NULL;
618 		if (lstat(abspath, &sb) == -1) {
619 			err = got_error_from_errno2("lstat", abspath);
620 		} else if (!S_ISDIR(sb.st_mode)) {
621 			/* TODO directory is obstructed; do something */
622 			err = got_error(GOT_ERR_FILE_OBSTRUCTED);
623 		}
624 	}
625 	free(abspath);
626 	return err;
627 }
628 
629 static const struct got_error *
630 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
631 {
632 	const struct got_error *err = NULL;
633 	uint8_t fbuf1[8192];
634 	uint8_t fbuf2[8192];
635 	size_t flen1 = 0, flen2 = 0;
636 
637 	*same = 1;
638 
639 	for (;;) {
640 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
641 		if (flen1 == 0 && ferror(f1)) {
642 			err = got_error_from_errno("fread");
643 			break;
644 		}
645 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
646 		if (flen2 == 0 && ferror(f2)) {
647 			err = got_error_from_errno("fread");
648 			break;
649 		}
650 		if (flen1 == 0) {
651 			if (flen2 != 0)
652 				*same = 0;
653 			break;
654 		} else if (flen2 == 0) {
655 			if (flen1 != 0)
656 				*same = 0;
657 			break;
658 		} else if (flen1 == flen2) {
659 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
660 				*same = 0;
661 				break;
662 			}
663 		} else {
664 			*same = 0;
665 			break;
666 		}
667 	}
668 
669 	return err;
670 }
671 
672 static const struct got_error *
673 check_files_equal(int *same, const char *f1_path, const char *f2_path)
674 {
675 	const struct got_error *err = NULL;
676 	struct stat sb;
677 	size_t size1, size2;
678 	FILE *f1 = NULL, *f2 = NULL;
679 
680 	*same = 1;
681 
682 	if (lstat(f1_path, &sb) != 0) {
683 		err = got_error_from_errno2("lstat", f1_path);
684 		goto done;
685 	}
686 	size1 = sb.st_size;
687 
688 	if (lstat(f2_path, &sb) != 0) {
689 		err = got_error_from_errno2("lstat", f2_path);
690 		goto done;
691 	}
692 	size2 = sb.st_size;
693 
694 	if (size1 != size2) {
695 		*same = 0;
696 		return NULL;
697 	}
698 
699 	f1 = fopen(f1_path, "r");
700 	if (f1 == NULL)
701 		return got_error_from_errno2("open", f1_path);
702 
703 	f2 = fopen(f2_path, "r");
704 	if (f2 == NULL) {
705 		err = got_error_from_errno2("open", f2_path);
706 		goto done;
707 	}
708 
709 	err = check_file_contents_equal(same, f1, f2);
710 done:
711 	if (f1 && fclose(f1) != 0 && err == NULL)
712 		err = got_error_from_errno("fclose");
713 	if (f2 && fclose(f2) != 0 && err == NULL)
714 		err = got_error_from_errno("fclose");
715 
716 	return err;
717 }
718 
719 /*
720  * Perform a 3-way merge where blob_orig acts as the common ancestor,
721  * blob_deriv acts as the first derived version, and the file on disk
722  * acts as the second derived version.
723  */
724 static const struct got_error *
725 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
726     struct got_blob_object *blob_orig, const char *ondisk_path,
727     const char *path, uint16_t st_mode, struct got_blob_object *blob_deriv,
728     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
729     void *progress_arg)
730 {
731 	const struct got_error *err = NULL;
732 	int merged_fd = -1;
733 	FILE *f_deriv = NULL, *f_orig = NULL;
734 	char *blob_deriv_path = NULL, *blob_orig_path = NULL;
735 	char *merged_path = NULL, *base_path = NULL;
736 	char *id_str = NULL;
737 	char *label1 = NULL;
738 	int overlapcnt = 0;
739 	char *parent;
740 
741 	*local_changes_subsumed = 0;
742 
743 	parent = dirname(ondisk_path);
744 	if (parent == NULL)
745 		return got_error_from_errno2("dirname", ondisk_path);
746 
747 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
748 		return got_error_from_errno("asprintf");
749 
750 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
751 	if (err)
752 		goto done;
753 
754 	free(base_path);
755 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
756 		err = got_error_from_errno("asprintf");
757 		base_path = NULL;
758 		goto done;
759 	}
760 
761 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path);
762 	if (err)
763 		goto done;
764 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
765 	    blob_deriv);
766 	if (err)
767 		goto done;
768 
769 	free(base_path);
770 	if (asprintf(&base_path, "%s/got-merge-blob-orig", parent) == -1) {
771 		err = got_error_from_errno("asprintf");
772 		base_path = NULL;
773 		goto done;
774 	}
775 
776 	err = got_opentemp_named(&blob_orig_path, &f_orig, base_path);
777 	if (err)
778 		goto done;
779 	if (blob_orig) {
780 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
781 		    blob_orig);
782 		if (err)
783 			goto done;
784 	} else {
785 		/*
786 		 * If the file has no blob, this is an "add vs add" conflict,
787 		 * and we simply use an empty ancestor file to make both files
788 		 * appear in the merged result in their entirety.
789 		 */
790 	}
791 
792 	err = got_object_id_str(&id_str, worktree->base_commit_id);
793 	if (err)
794 		goto done;
795 	if (asprintf(&label1, "commit %s", id_str) == -1) {
796 		err = got_error_from_errno("asprintf");
797 		goto done;
798 	}
799 
800 	err = got_merge_diff3(&overlapcnt, merged_fd, blob_deriv_path,
801 	    blob_orig_path, ondisk_path, label1, path);
802 	if (err)
803 		goto done;
804 
805 	(*progress_cb)(progress_arg,
806 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
807 
808 	if (fsync(merged_fd) != 0) {
809 		err = got_error_from_errno("fsync");
810 		goto done;
811 	}
812 
813 	/* Check if a clean merge has subsumed all local changes. */
814 	if (overlapcnt == 0) {
815 		err = check_files_equal(local_changes_subsumed, blob_deriv_path,
816 		    merged_path);
817 		if (err)
818 			goto done;
819 	}
820 
821 	if (chmod(merged_path, st_mode) != 0) {
822 		err = got_error_from_errno2("chmod", merged_path);
823 		goto done;
824 	}
825 
826 	if (rename(merged_path, ondisk_path) != 0) {
827 		err = got_error_from_errno3("rename", merged_path,
828 		    ondisk_path);
829 		unlink(merged_path);
830 		goto done;
831 	}
832 
833 done:
834 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
835 		err = got_error_from_errno("close");
836 	if (f_deriv && fclose(f_deriv) != 0 && err == NULL)
837 		err = got_error_from_errno("fclose");
838 	if (f_orig && fclose(f_orig) != 0 && err == NULL)
839 		err = got_error_from_errno("fclose");
840 	free(merged_path);
841 	free(base_path);
842 	if (blob_deriv_path) {
843 		unlink(blob_deriv_path);
844 		free(blob_deriv_path);
845 	}
846 	if (blob_orig_path) {
847 		unlink(blob_orig_path);
848 		free(blob_orig_path);
849 	}
850 	free(id_str);
851 	free(label1);
852 	return err;
853 }
854 
855 static const struct got_error *
856 update_blob_fileindex_entry(struct got_worktree *worktree,
857     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
858     const char *ondisk_path, const char *path, struct got_blob_object *blob,
859     int update_timestamps)
860 {
861 	const struct got_error *err = NULL;
862 
863 	if (ie == NULL)
864 		ie = got_fileindex_entry_get(fileindex, path);
865 	if (ie)
866 		err = got_fileindex_entry_update(ie, ondisk_path,
867 		    blob->id.sha1, worktree->base_commit_id->sha1,
868 		    update_timestamps);
869 	else {
870 		struct got_fileindex_entry *new_ie;
871 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
872 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
873 		if (!err)
874 			err = got_fileindex_entry_add(fileindex, new_ie);
875 	}
876 	return err;
877 }
878 
879 static const struct got_error *
880 install_blob(struct got_worktree *worktree, const char *ondisk_path,
881    const char *path, uint16_t te_mode, uint16_t st_mode,
882    struct got_blob_object *blob, int restoring_missing_file,
883    int reverting_versioned_file, struct got_repository *repo,
884    got_worktree_checkout_cb progress_cb, void *progress_arg)
885 {
886 	const struct got_error *err = NULL;
887 	int fd = -1;
888 	size_t len, hdrlen;
889 	int update = 0;
890 	char *tmppath = NULL;
891 
892 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
893 	    GOT_DEFAULT_FILE_MODE);
894 	if (fd == -1) {
895 		if (errno == ENOENT) {
896 			char *parent = dirname(path);
897 			if (parent == NULL)
898 				return got_error_from_errno2("dirname", path);
899 			err = add_dir_on_disk(worktree, parent);
900 			if (err)
901 				return err;
902 			fd = open(ondisk_path,
903 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
904 			    GOT_DEFAULT_FILE_MODE);
905 			if (fd == -1)
906 				return got_error_from_errno2("open",
907 				    ondisk_path);
908 		} else if (errno == EEXIST) {
909 			if (!S_ISREG(st_mode)) {
910 				/* TODO file is obstructed; do something */
911 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
912 				goto done;
913 			} else {
914 				err = got_opentemp_named_fd(&tmppath, &fd,
915 				    ondisk_path);
916 				if (err)
917 					goto done;
918 				update = 1;
919 			}
920 		} else
921 			return got_error_from_errno2("open", ondisk_path);
922 	}
923 
924 	if (restoring_missing_file)
925 		(*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
926 	else if (reverting_versioned_file)
927 		(*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
928 	else
929 		(*progress_cb)(progress_arg,
930 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
931 
932 	hdrlen = got_object_blob_get_hdrlen(blob);
933 	do {
934 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
935 		err = got_object_blob_read_block(&len, blob);
936 		if (err)
937 			break;
938 		if (len > 0) {
939 			/* Skip blob object header first time around. */
940 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
941 			if (outlen == -1) {
942 				err = got_error_from_errno("write");
943 				goto done;
944 			} else if (outlen != len - hdrlen) {
945 				err = got_error(GOT_ERR_IO);
946 				goto done;
947 			}
948 			hdrlen = 0;
949 		}
950 	} while (len != 0);
951 
952 	if (fsync(fd) != 0) {
953 		err = got_error_from_errno("fsync");
954 		goto done;
955 	}
956 
957 	if (update) {
958 		if (rename(tmppath, ondisk_path) != 0) {
959 			err = got_error_from_errno3("rename", tmppath,
960 			    ondisk_path);
961 			unlink(tmppath);
962 			goto done;
963 		}
964 	}
965 
966 	if (te_mode & S_IXUSR) {
967 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
968 			err = got_error_from_errno2("chmod", ondisk_path);
969 			goto done;
970 		}
971 	} else {
972 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
973 			err = got_error_from_errno2("chmod", ondisk_path);
974 			goto done;
975 		}
976 	}
977 
978 done:
979 	if (fd != -1 && close(fd) != 0 && err == NULL)
980 		err = got_error_from_errno("close");
981 	free(tmppath);
982 	return err;
983 }
984 
985 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
986 static const struct got_error *
987 get_modified_file_content_status(unsigned char *status, FILE *f)
988 {
989 	const struct got_error *err = NULL;
990 	const char *markers[3] = {
991 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
992 		GOT_DIFF_CONFLICT_MARKER_SEP,
993 		GOT_DIFF_CONFLICT_MARKER_END
994 	};
995 	int i = 0;
996 	char *line;
997 	size_t len;
998 	const char delim[3] = {'\0', '\0', '\0'};
999 
1000 	while (*status == GOT_STATUS_MODIFY) {
1001 		line = fparseln(f, &len, NULL, delim, 0);
1002 		if (line == NULL) {
1003 			if (feof(f))
1004 				break;
1005 			err = got_ferror(f, GOT_ERR_IO);
1006 			break;
1007 		}
1008 
1009 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1010 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1011 			    == 0)
1012 				*status = GOT_STATUS_CONFLICT;
1013 			else
1014 				i++;
1015 		}
1016 	}
1017 
1018 	return err;
1019 }
1020 
1021 static const struct got_error *
1022 get_file_status(unsigned char *status, struct stat *sb,
1023     struct got_fileindex_entry *ie, const char *abspath,
1024     struct got_repository *repo)
1025 {
1026 	const struct got_error *err = NULL;
1027 	struct got_object_id id;
1028 	size_t hdrlen;
1029 	FILE *f = NULL;
1030 	uint8_t fbuf[8192];
1031 	struct got_blob_object *blob = NULL;
1032 	size_t flen, blen;
1033 
1034 	*status = GOT_STATUS_NO_CHANGE;
1035 
1036 	if (lstat(abspath, sb) == -1) {
1037 		if (errno == ENOENT) {
1038 			if (ie) {
1039 				if (got_fileindex_entry_has_file_on_disk(ie))
1040 					*status = GOT_STATUS_MISSING;
1041 				else
1042 					*status = GOT_STATUS_DELETE;
1043 				sb->st_mode =
1044 				    ((ie->mode >> GOT_FILEIDX_MODE_PERMS_SHIFT)
1045 				    & (S_IRWXU | S_IRWXG | S_IRWXO));
1046 			} else
1047 				sb->st_mode = GOT_DEFAULT_FILE_MODE;
1048 			return NULL;
1049 		}
1050 		return got_error_from_errno2("lstat", abspath);
1051 	}
1052 
1053 	if (!S_ISREG(sb->st_mode)) {
1054 		*status = GOT_STATUS_OBSTRUCTED;
1055 		return NULL;
1056 	}
1057 
1058 	if (ie == NULL)
1059 		return NULL;
1060 
1061 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1062 		*status = GOT_STATUS_DELETE;
1063 		return NULL;
1064 	} else if (!got_fileindex_entry_has_blob(ie)) {
1065 		*status = GOT_STATUS_ADD;
1066 		return NULL;
1067 	}
1068 
1069 	if (ie->ctime_sec == sb->st_ctime &&
1070 	    ie->ctime_nsec == sb->st_ctimensec &&
1071 	    ie->mtime_sec == sb->st_mtime &&
1072 	    ie->mtime_sec == sb->st_mtime &&
1073 	    ie->mtime_nsec == sb->st_mtimensec &&
1074 	    ie->size == (sb->st_size & 0xffffffff))
1075 		return NULL;
1076 
1077 	memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1078 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1079 	if (err)
1080 		return err;
1081 
1082 	f = fopen(abspath, "r");
1083 	if (f == NULL) {
1084 		err = got_error_from_errno2("fopen", abspath);
1085 		goto done;
1086 	}
1087 	hdrlen = got_object_blob_get_hdrlen(blob);
1088 	for (;;) {
1089 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1090 		err = got_object_blob_read_block(&blen, blob);
1091 		if (err)
1092 			goto done;
1093 		/* Skip length of blob object header first time around. */
1094 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1095 		if (flen == 0 && ferror(f)) {
1096 			err = got_error_from_errno("fread");
1097 			goto done;
1098 		}
1099 		if (blen == 0) {
1100 			if (flen != 0)
1101 				*status = GOT_STATUS_MODIFY;
1102 			break;
1103 		} else if (flen == 0) {
1104 			if (blen != 0)
1105 				*status = GOT_STATUS_MODIFY;
1106 			break;
1107 		} else if (blen - hdrlen == flen) {
1108 			/* Skip blob object header first time around. */
1109 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1110 				*status = GOT_STATUS_MODIFY;
1111 				break;
1112 			}
1113 		} else {
1114 			*status = GOT_STATUS_MODIFY;
1115 			break;
1116 		}
1117 		hdrlen = 0;
1118 	}
1119 
1120 	if (*status == GOT_STATUS_MODIFY) {
1121 		rewind(f);
1122 		err = get_modified_file_content_status(status, f);
1123 	}
1124 done:
1125 	if (blob)
1126 		got_object_blob_close(blob);
1127 	if (f)
1128 		fclose(f);
1129 	return err;
1130 }
1131 
1132 static const struct got_error *
1133 update_blob(struct got_worktree *worktree,
1134     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1135     struct got_tree_entry *te, const char *path,
1136     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1137     void *progress_arg)
1138 {
1139 	const struct got_error *err = NULL;
1140 	struct got_blob_object *blob = NULL;
1141 	char *ondisk_path;
1142 	unsigned char status = GOT_STATUS_NO_CHANGE;
1143 	struct stat sb;
1144 
1145 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1146 		return got_error_from_errno("asprintf");
1147 
1148 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1149 	if (err)
1150 		goto done;
1151 
1152 	if (status == GOT_STATUS_OBSTRUCTED) {
1153 		(*progress_cb)(progress_arg, status, path);
1154 		goto done;
1155 	}
1156 
1157 	if (ie && status != GOT_STATUS_MISSING) {
1158 		if (got_fileindex_entry_has_commit(ie) &&
1159 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1160 		    SHA1_DIGEST_LENGTH) == 0) {
1161 			(*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1162 			    path);
1163 			goto done;
1164 		}
1165 		if (got_fileindex_entry_has_blob(ie) &&
1166 		    memcmp(ie->blob_sha1, te->id->sha1,
1167 		    SHA1_DIGEST_LENGTH) == 0)
1168 			goto done;
1169 	}
1170 
1171 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1172 	if (err)
1173 		goto done;
1174 
1175 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1176 		int update_timestamps;
1177 		struct got_blob_object *blob2 = NULL;
1178 		if (got_fileindex_entry_has_blob(ie)) {
1179 			struct got_object_id id2;
1180 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1181 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
1182 			if (err)
1183 				goto done;
1184 		}
1185 		err = merge_blob(&update_timestamps, worktree, blob2,
1186 		    ondisk_path, path, sb.st_mode, blob, repo,
1187 		    progress_cb, progress_arg);
1188 		if (blob2)
1189 			got_object_blob_close(blob2);
1190 		/*
1191 		 * Do not update timestamps of files with local changes.
1192 		 * Otherwise, a future status walk would treat them as
1193 		 * unmodified files again.
1194 		 */
1195 		err = got_fileindex_entry_update(ie, ondisk_path,
1196 		    blob->id.sha1, worktree->base_commit_id->sha1,
1197 		    update_timestamps);
1198 	} else if (status == GOT_STATUS_DELETE) {
1199 		(*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1200 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1201 		    ondisk_path, path, blob, 0);
1202 		if (err)
1203 			goto done;
1204 	} else {
1205 		err = install_blob(worktree, ondisk_path, path, te->mode,
1206 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1207 		    repo, progress_cb, progress_arg);
1208 		if (err)
1209 			goto done;
1210 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1211 		    ondisk_path, path, blob, 1);
1212 		if (err)
1213 			goto done;
1214 	}
1215 	got_object_blob_close(blob);
1216 done:
1217 	free(ondisk_path);
1218 	return err;
1219 }
1220 
1221 static const struct got_error *
1222 remove_ondisk_file(const char *root_path, const char *path)
1223 {
1224 	const struct got_error *err = NULL;
1225 	char *ondisk_path = NULL;
1226 
1227 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1228 		return got_error_from_errno("asprintf");
1229 
1230 	if (unlink(ondisk_path) == -1) {
1231 		if (errno != ENOENT)
1232 			err = got_error_from_errno2("unlink", ondisk_path);
1233 	} else {
1234 		char *parent = dirname(ondisk_path);
1235 		while (parent && strcmp(parent, root_path) != 0) {
1236 			if (rmdir(parent) == -1) {
1237 				if (errno != ENOTEMPTY)
1238 					err = got_error_from_errno2("rmdir",
1239 					    parent);
1240 				break;
1241 			}
1242 			parent = dirname(parent);
1243 		}
1244 	}
1245 	free(ondisk_path);
1246 	return err;
1247 }
1248 
1249 static const struct got_error *
1250 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1251     struct got_fileindex_entry *ie, struct got_repository *repo,
1252     got_worktree_checkout_cb progress_cb, void *progress_arg)
1253 {
1254 	const struct got_error *err = NULL;
1255 	unsigned char status;
1256 	struct stat sb;
1257 	char *ondisk_path;
1258 
1259 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1260 	    == -1)
1261 		return got_error_from_errno("asprintf");
1262 
1263 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1264 	if (err)
1265 		return err;
1266 
1267 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1268 	    status == GOT_STATUS_ADD) {
1269 		(*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1270 		/*
1271 		 * Preserve the working file and change the deleted blob's
1272 		 * entry into a schedule-add entry.
1273 		 */
1274 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1275 		    0);
1276 		if (err)
1277 			return err;
1278 	} else {
1279 		(*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1280 		if (status == GOT_STATUS_NO_CHANGE) {
1281 			err = remove_ondisk_file(worktree->root_path, ie->path);
1282 			if (err)
1283 				return err;
1284 		}
1285 		got_fileindex_entry_remove(fileindex, ie);
1286 	}
1287 
1288 	return err;
1289 }
1290 
1291 struct diff_cb_arg {
1292     struct got_fileindex *fileindex;
1293     struct got_worktree *worktree;
1294     struct got_repository *repo;
1295     got_worktree_checkout_cb progress_cb;
1296     void *progress_arg;
1297     got_worktree_cancel_cb cancel_cb;
1298     void *cancel_arg;
1299 };
1300 
1301 static const struct got_error *
1302 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1303     struct got_tree_entry *te, const char *parent_path)
1304 {
1305 	struct diff_cb_arg *a = arg;
1306 
1307 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1308 		return got_error(GOT_ERR_CANCELLED);
1309 
1310 	return update_blob(a->worktree, a->fileindex, ie, te,
1311 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1312 }
1313 
1314 static const struct got_error *
1315 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1316 {
1317 	struct diff_cb_arg *a = arg;
1318 
1319 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1320 		return got_error(GOT_ERR_CANCELLED);
1321 
1322 	return delete_blob(a->worktree, a->fileindex, ie,
1323 	    a->repo, a->progress_cb, a->progress_arg);
1324 }
1325 
1326 static const struct got_error *
1327 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1328 {
1329 	struct diff_cb_arg *a = arg;
1330 	const struct got_error *err;
1331 	char *path;
1332 
1333 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1334 		return got_error(GOT_ERR_CANCELLED);
1335 
1336 	if (asprintf(&path, "%s%s%s", parent_path,
1337 	    parent_path[0] ? "/" : "", te->name)
1338 	    == -1)
1339 		return got_error_from_errno("asprintf");
1340 
1341 	if (S_ISDIR(te->mode))
1342 		err = add_dir_on_disk(a->worktree, path);
1343 	else
1344 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1345 		    a->repo, a->progress_cb, a->progress_arg);
1346 
1347 	free(path);
1348 	return err;
1349 }
1350 
1351 const struct got_error *
1352 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1353 {
1354 	const struct got_error *err = NULL;
1355 	char *uuidstr = NULL;
1356 	uint32_t uuid_status;
1357 
1358 	*refname = NULL;
1359 
1360 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1361 	if (uuid_status != uuid_s_ok)
1362 		return got_error_uuid(uuid_status);
1363 
1364 	if (asprintf(refname, "%s-%s", GOT_WORKTREE_BASE_REF_PREFIX, uuidstr)
1365 	    == -1) {
1366 		err = got_error_from_errno("asprintf");
1367 		*refname = NULL;
1368 	}
1369 	free(uuidstr);
1370 	return err;
1371 }
1372 
1373 /*
1374  * Prevent Git's garbage collector from deleting our base commit by
1375  * setting a reference to our base commit's ID.
1376  */
1377 static const struct got_error *
1378 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1379 {
1380 	const struct got_error *err = NULL;
1381 	struct got_reference *ref = NULL;
1382 	char *refname;
1383 
1384 	err = got_worktree_get_base_ref_name(&refname, worktree);
1385 	if (err)
1386 		return err;
1387 
1388 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1389 	if (err)
1390 		goto done;
1391 
1392 	err = got_ref_write(ref, repo);
1393 done:
1394 	free(refname);
1395 	if (ref)
1396 		got_ref_close(ref);
1397 	return err;
1398 }
1399 
1400 static const struct got_error *
1401 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1402    struct got_worktree *worktree)
1403 {
1404 	const struct got_error *err = NULL;
1405 	FILE *index = NULL;
1406 
1407 	*fileindex_path = NULL;
1408 	*fileindex = got_fileindex_alloc();
1409 	if (*fileindex == NULL)
1410 		return got_error_from_errno("got_fileindex_alloc");
1411 
1412 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1413 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1414 		err = got_error_from_errno("asprintf");
1415 		*fileindex_path = NULL;
1416 		goto done;
1417 	}
1418 
1419 	index = fopen(*fileindex_path, "rb");
1420 	if (index == NULL) {
1421 		if (errno != ENOENT)
1422 			err = got_error_from_errno2("fopen", *fileindex_path);
1423 	} else {
1424 		err = got_fileindex_read(*fileindex, index);
1425 		if (fclose(index) != 0 && err == NULL)
1426 			err = got_error_from_errno("fclose");
1427 	}
1428 done:
1429 	if (err) {
1430 		free(*fileindex_path);
1431 		*fileindex_path = NULL;
1432 		free(*fileindex);
1433 		*fileindex = NULL;
1434 	}
1435 	return err;
1436 }
1437 
1438 struct bump_base_commit_id_arg {
1439 	struct got_object_id *base_commit_id;
1440 	const char *path;
1441 	size_t path_len;
1442 	const char *entry_name;
1443 	got_worktree_checkout_cb progress_cb;
1444 	void *progress_arg;
1445 };
1446 
1447 /* Bump base commit ID of all files within an updated part of the work tree. */
1448 static const struct got_error *
1449 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1450 {
1451 	struct bump_base_commit_id_arg *a = arg;
1452 
1453 	if (a->entry_name) {
1454 		if (strcmp(ie->path, a->path) != 0)
1455 			return NULL;
1456 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1457 		return NULL;
1458 
1459 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
1460 	    SHA1_DIGEST_LENGTH) == 0)
1461 		return NULL;
1462 
1463 	(*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE, ie->path);
1464 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1465 	return NULL;
1466 }
1467 
1468 static const struct got_error *
1469 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
1470 {
1471 	const struct got_error *err = NULL;
1472 	char *new_fileindex_path = NULL;
1473 	FILE *new_index = NULL;
1474 
1475 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1476 	    fileindex_path);
1477 	if (err)
1478 		goto done;
1479 
1480 	err = got_fileindex_write(fileindex, new_index);
1481 	if (err)
1482 		goto done;
1483 
1484 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1485 		err = got_error_from_errno3("rename", new_fileindex_path,
1486 		    fileindex_path);
1487 		unlink(new_fileindex_path);
1488 	}
1489 done:
1490 	if (new_index)
1491 		fclose(new_index);
1492 	free(new_fileindex_path);
1493 	return err;
1494 }
1495 
1496 const struct got_error *
1497 got_worktree_checkout_files(struct got_worktree *worktree, const char *path,
1498     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1499     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1500 {
1501 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1502 	struct got_commit_object *commit = NULL;
1503 	struct got_object_id *tree_id = NULL;
1504 	struct got_tree_object *tree = NULL;
1505 	struct got_fileindex *fileindex = NULL;
1506 	char *fileindex_path = NULL;
1507 	struct got_fileindex_diff_tree_cb diff_cb;
1508 	struct diff_cb_arg arg;
1509 	char *relpath = NULL, *entry_name = NULL;
1510 	struct bump_base_commit_id_arg bbc_arg;
1511 
1512 	err = lock_worktree(worktree, LOCK_EX);
1513 	if (err)
1514 		return err;
1515 
1516 	/*
1517 	 * Read the file index.
1518 	 * Checking out files is supposed to be an idempotent operation.
1519 	 * If the on-disk file index is incomplete we will try to complete it.
1520 	 */
1521 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1522 	if (err)
1523 		goto done;
1524 
1525 	err = ref_base_commit(worktree, repo);
1526 	if (err)
1527 		goto done;
1528 
1529 	err = got_object_open_as_commit(&commit, repo,
1530 	   worktree->base_commit_id);
1531 	if (err)
1532 		goto done;
1533 
1534 	if (path[0]) {
1535 		char *tree_path;
1536 		int obj_type;
1537 		relpath = strdup(path);
1538 		if (relpath == NULL) {
1539 			err = got_error_from_errno("strdup");
1540 			goto done;
1541 		}
1542 		if (asprintf(&tree_path, "%s%s%s", worktree->path_prefix,
1543 		    got_path_is_root_dir(worktree->path_prefix) ? "" : "/",
1544 		    path) == -1) {
1545 			err = got_error_from_errno("asprintf");
1546 			goto done;
1547 		}
1548 		err = got_object_id_by_path(&tree_id, repo,
1549 		    worktree->base_commit_id, tree_path);
1550 		free(tree_path);
1551 		if (err)
1552 			goto done;
1553 		err = got_object_get_type(&obj_type, repo, tree_id);
1554 		if (err)
1555 			goto done;
1556 		if (obj_type == GOT_OBJ_TYPE_BLOB) {
1557 			/* Split provided path into parent dir + entry name. */
1558 			if (strchr(path, '/')  == NULL) {
1559 				relpath = strdup("");
1560 				if (relpath == NULL) {
1561 					err = got_error_from_errno("strdup");
1562 					goto done;
1563 				}
1564 				tree_path = strdup(worktree->path_prefix);
1565 				if (tree_path == NULL) {
1566 					err = got_error_from_errno("strdup");
1567 					goto done;
1568 				}
1569 			} else {
1570 				err = got_path_dirname(&relpath, path);
1571 				if (err)
1572 					goto done;
1573 				if (asprintf(&tree_path, "%s%s%s",
1574 				    worktree->path_prefix,
1575 				    got_path_is_root_dir(
1576 				    worktree->path_prefix) ? "" : "/",
1577 				    relpath) == -1) {
1578 					err = got_error_from_errno("asprintf");
1579 					goto done;
1580 				}
1581 			}
1582 			err = got_object_id_by_path(&tree_id, repo,
1583 			    worktree->base_commit_id, tree_path);
1584 			free(tree_path);
1585 			if (err)
1586 				goto done;
1587 			entry_name = basename(path);
1588 			if (entry_name == NULL) {
1589 				err = got_error_from_errno2("basename", path);
1590 				goto done;
1591 			}
1592 		}
1593 	} else {
1594 		relpath = strdup("");
1595 		if (relpath == NULL) {
1596 			err = got_error_from_errno("strdup");
1597 			goto done;
1598 		}
1599 		err = got_object_id_by_path(&tree_id, repo,
1600 		    worktree->base_commit_id, worktree->path_prefix);
1601 		if (err)
1602 			goto done;
1603 	}
1604 
1605 	err = got_object_open_as_tree(&tree, repo, tree_id);
1606 	if (err)
1607 		goto done;
1608 
1609 	if (entry_name &&
1610 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1611 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1612 		goto done;
1613 	}
1614 
1615 	diff_cb.diff_old_new = diff_old_new;
1616 	diff_cb.diff_old = diff_old;
1617 	diff_cb.diff_new = diff_new;
1618 	arg.fileindex = fileindex;
1619 	arg.worktree = worktree;
1620 	arg.repo = repo;
1621 	arg.progress_cb = progress_cb;
1622 	arg.progress_arg = progress_arg;
1623 	arg.cancel_cb = cancel_cb;
1624 	arg.cancel_arg = cancel_arg;
1625 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
1626 	    entry_name, repo, &diff_cb, &arg);
1627 	if (err)
1628 		goto sync;
1629 
1630 	bbc_arg.base_commit_id = worktree->base_commit_id;
1631 	bbc_arg.entry_name = entry_name;
1632 	bbc_arg.path = path;
1633 	bbc_arg.path_len = strlen(path);
1634 	bbc_arg.progress_cb = progress_cb;
1635 	bbc_arg.progress_arg = progress_arg;
1636 	err = got_fileindex_for_each_entry_safe(fileindex,
1637 	    bump_base_commit_id, &bbc_arg);
1638 sync:
1639 	sync_err = sync_fileindex(fileindex, fileindex_path);
1640 	if (sync_err && err == NULL)
1641 		err = sync_err;
1642 done:
1643 	free(fileindex_path);
1644 	free(relpath);
1645 	if (tree)
1646 		got_object_tree_close(tree);
1647 	if (commit)
1648 		got_object_commit_close(commit);
1649 	got_fileindex_free(fileindex);
1650 	unlockerr = lock_worktree(worktree, LOCK_SH);
1651 	if (unlockerr && err == NULL)
1652 		err = unlockerr;
1653 	return err;
1654 }
1655 
1656 struct merge_file_cb_arg {
1657     struct got_worktree *worktree;
1658     struct got_fileindex *fileindex;
1659     got_worktree_checkout_cb progress_cb;
1660     void *progress_arg;
1661     got_worktree_cancel_cb cancel_cb;
1662     void *cancel_arg;
1663 };
1664 
1665 static const struct got_error *
1666 merge_file_cb(void *arg, struct got_blob_object *blob1,
1667     struct got_blob_object *blob2, struct got_object_id *id1,
1668     struct got_object_id *id2, const char *path1, const char *path2,
1669     struct got_repository *repo)
1670 {
1671 	static const struct got_error *err = NULL;
1672 	struct merge_file_cb_arg *a = arg;
1673 	struct got_fileindex_entry *ie;
1674 	char *ondisk_path = NULL;
1675 	struct stat sb;
1676 	unsigned char status;
1677 	int local_changes_subsumed;
1678 
1679 	if (blob1 && blob2) {
1680 		ie = got_fileindex_entry_get(a->fileindex, path2);
1681 		if (ie == NULL) {
1682 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_MISSING,
1683 			    path2);
1684 			return NULL;
1685 		}
1686 
1687 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1688 		    path2) == -1)
1689 			return got_error_from_errno("asprintf");
1690 
1691 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1692 		if (err)
1693 			goto done;
1694 
1695 		if (status == GOT_STATUS_DELETE) {
1696 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_MERGE,
1697 			    path2);
1698 			goto done;
1699 		}
1700 		if (status != GOT_STATUS_NO_CHANGE &&
1701 		    status != GOT_STATUS_MODIFY &&
1702 		    status != GOT_STATUS_CONFLICT &&
1703 		    status != GOT_STATUS_ADD) {
1704 			(*a->progress_cb)(a->progress_arg, status, path2);
1705 			goto done;
1706 		}
1707 
1708 		err = merge_blob(&local_changes_subsumed, a->worktree, blob1,
1709 		    ondisk_path, path2, sb.st_mode, blob2, repo,
1710 		    a->progress_cb, a->progress_arg);
1711 	} else if (blob1) {
1712 		ie = got_fileindex_entry_get(a->fileindex, path1);
1713 		if (ie == NULL) {
1714 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_MISSING,
1715 			    path2);
1716 			return NULL;
1717 		}
1718 
1719 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1720 		    path1) == -1)
1721 			return got_error_from_errno("asprintf");
1722 
1723 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1724 		if (err)
1725 			goto done;
1726 
1727 		switch (status) {
1728 		case GOT_STATUS_NO_CHANGE:
1729 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
1730 			    path1);
1731 			err = remove_ondisk_file(a->worktree->root_path, path1);
1732 			if (err)
1733 				goto done;
1734 			if (ie)
1735 				got_fileindex_entry_mark_deleted_from_disk(ie);
1736 			break;
1737 		case GOT_STATUS_DELETE:
1738 		case GOT_STATUS_MISSING:
1739 			(*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
1740 			    path1);
1741 			if (ie)
1742 				got_fileindex_entry_mark_deleted_from_disk(ie);
1743 			break;
1744 		case GOT_STATUS_ADD:
1745 		case GOT_STATUS_MODIFY:
1746 		case GOT_STATUS_CONFLICT:
1747 			(*a->progress_cb)(a->progress_arg,
1748 			    GOT_STATUS_CANNOT_DELETE, path1);
1749 			break;
1750 		case GOT_STATUS_OBSTRUCTED:
1751 			(*a->progress_cb)(a->progress_arg, status, path1);
1752 			break;
1753 		default:
1754 			break;
1755 		}
1756 	} else if (blob2) {
1757 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1758 		    path2) == -1)
1759 			return got_error_from_errno("asprintf");
1760 		ie = got_fileindex_entry_get(a->fileindex, path2);
1761 		if (ie) {
1762 			err = get_file_status(&status, &sb, ie, ondisk_path,
1763 			    repo);
1764 			if (err)
1765 				goto done;
1766 			if (status != GOT_STATUS_NO_CHANGE &&
1767 			    status != GOT_STATUS_MODIFY &&
1768 			    status != GOT_STATUS_CONFLICT &&
1769 			    status != GOT_STATUS_ADD) {
1770 				(*a->progress_cb)(a->progress_arg, status,
1771 				    path2);
1772 				goto done;
1773 			}
1774 			err = merge_blob(&local_changes_subsumed, a->worktree,
1775 			    NULL, ondisk_path, path2, sb.st_mode, blob2, repo,
1776 			    a->progress_cb, a->progress_arg);
1777 			if (status == GOT_STATUS_DELETE) {
1778 				err = update_blob_fileindex_entry(a->worktree,
1779 				    a->fileindex, ie, ondisk_path, ie->path,
1780 				    blob2, 0);
1781 				if (err)
1782 					goto done;
1783 			}
1784 		} else {
1785 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1786 			err = install_blob(a->worktree, ondisk_path, path2,
1787 			    /* XXX get this from parent tree! */
1788 			    GOT_DEFAULT_FILE_MODE,
1789 			    sb.st_mode, blob2, 0, 0, repo,
1790 			    a->progress_cb, a->progress_arg);
1791 			if (err)
1792 				goto done;
1793 			err = got_fileindex_entry_alloc(&ie,
1794 			    ondisk_path, path2, NULL, NULL);
1795 			if (err)
1796 				goto done;
1797 			err = got_fileindex_entry_add(a->fileindex, ie);
1798 			if (err) {
1799 				got_fileindex_entry_free(ie);
1800 				goto done;
1801 			}
1802 		}
1803 	}
1804 done:
1805 	free(ondisk_path);
1806 	return err;
1807 }
1808 
1809 struct check_merge_ok_arg {
1810 	struct got_worktree *worktree;
1811 	struct got_repository *repo;
1812 };
1813 
1814 static const struct got_error *
1815 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
1816 {
1817 	const struct got_error *err = NULL;
1818 	struct check_merge_ok_arg *a = arg;
1819 	unsigned char status;
1820 	struct stat sb;
1821 	char *ondisk_path;
1822 
1823 	/* Reject merges into a work tree with mixed base commits. */
1824 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
1825 	    SHA1_DIGEST_LENGTH))
1826 		return got_error(GOT_ERR_MIXED_COMMITS);
1827 
1828 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
1829 	    == -1)
1830 		return got_error_from_errno("asprintf");
1831 
1832 	/* Reject merges into a work tree with conflicted files. */
1833 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
1834 	if (err)
1835 		return err;
1836 	if (status == GOT_STATUS_CONFLICT)
1837 		return got_error(GOT_ERR_CONFLICTS);
1838 
1839 	return NULL;
1840 }
1841 
1842 const struct got_error *
1843 got_worktree_merge_files(struct got_worktree *worktree,
1844     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
1845     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1846     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1847 {
1848 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1849 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
1850 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
1851 	struct merge_file_cb_arg arg;
1852 	char *fileindex_path = NULL;
1853 	struct got_fileindex *fileindex = NULL;
1854 	struct check_merge_ok_arg mok_arg;
1855 
1856 	err = lock_worktree(worktree, LOCK_EX);
1857 	if (err)
1858 		return err;
1859 
1860 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1861 	if (err)
1862 		goto done;
1863 
1864 	mok_arg.worktree = worktree;
1865 	mok_arg.repo = repo;
1866 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
1867 	    &mok_arg);
1868 	if (err)
1869 		goto done;
1870 
1871 	if (commit_id1) {
1872 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
1873 		    worktree->path_prefix);
1874 		if (err)
1875 			goto done;
1876 
1877 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
1878 		if (err)
1879 			goto done;
1880 	}
1881 
1882 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
1883 	    worktree->path_prefix);
1884 	if (err)
1885 		goto done;
1886 
1887 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
1888 	if (err)
1889 		goto done;
1890 
1891 	arg.worktree = worktree;
1892 	arg.fileindex = fileindex;
1893 	arg.progress_cb = progress_cb;
1894 	arg.progress_arg = progress_arg;
1895 	arg.cancel_cb = cancel_cb;
1896 	arg.cancel_arg = cancel_arg;
1897 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg);
1898 	sync_err = sync_fileindex(fileindex, fileindex_path);
1899 	if (sync_err && err == NULL)
1900 		err = sync_err;
1901 done:
1902 	got_fileindex_free(fileindex);
1903 	if (tree1)
1904 		got_object_tree_close(tree1);
1905 	if (tree2)
1906 		got_object_tree_close(tree2);
1907 
1908 	unlockerr = lock_worktree(worktree, LOCK_SH);
1909 	if (unlockerr && err == NULL)
1910 		err = unlockerr;
1911 	return err;
1912 }
1913 
1914 struct diff_dir_cb_arg {
1915     struct got_fileindex *fileindex;
1916     struct got_worktree *worktree;
1917     const char *status_path;
1918     size_t status_path_len;
1919     struct got_repository *repo;
1920     got_worktree_status_cb status_cb;
1921     void *status_arg;
1922     got_worktree_cancel_cb cancel_cb;
1923     void *cancel_arg;
1924 };
1925 
1926 static const struct got_error *
1927 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
1928     got_worktree_status_cb status_cb, void *status_arg,
1929     struct got_repository *repo)
1930 {
1931 	const struct got_error *err = NULL;
1932 	unsigned char status = GOT_STATUS_NO_CHANGE;
1933 	struct stat sb;
1934 	struct got_object_id blob_id, commit_id;
1935 
1936 	err = get_file_status(&status, &sb, ie, abspath, repo);
1937 	if (err == NULL && status != GOT_STATUS_NO_CHANGE) {
1938 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1939 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
1940 		err = (*status_cb)(status_arg, status, ie->path, &blob_id,
1941 		    &commit_id);
1942 	}
1943 	return err;
1944 }
1945 
1946 static const struct got_error *
1947 status_old_new(void *arg, struct got_fileindex_entry *ie,
1948     struct dirent *de, const char *parent_path)
1949 {
1950 	const struct got_error *err = NULL;
1951 	struct diff_dir_cb_arg *a = arg;
1952 	char *abspath;
1953 
1954 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1955 		return got_error(GOT_ERR_CANCELLED);
1956 
1957 	if (got_path_cmp(parent_path, a->status_path) != 0 &&
1958 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
1959 		return NULL;
1960 
1961 	if (parent_path[0]) {
1962 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
1963 		    parent_path, de->d_name) == -1)
1964 			return got_error_from_errno("asprintf");
1965 	} else {
1966 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
1967 		    de->d_name) == -1)
1968 			return got_error_from_errno("asprintf");
1969 	}
1970 
1971 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
1972 	    a->repo);
1973 	free(abspath);
1974 	return err;
1975 }
1976 
1977 static const struct got_error *
1978 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1979 {
1980 	struct diff_dir_cb_arg *a = arg;
1981 	struct got_object_id blob_id, commit_id;
1982 	unsigned char status;
1983 
1984 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1985 		return got_error(GOT_ERR_CANCELLED);
1986 
1987 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
1988 		return NULL;
1989 
1990 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1991 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
1992 	if (got_fileindex_entry_has_file_on_disk(ie))
1993 		status = GOT_STATUS_MISSING;
1994 	else
1995 		status = GOT_STATUS_DELETE;
1996 	return (*a->status_cb)(a->status_arg, status, ie->path, &blob_id,
1997 	    &commit_id);
1998 }
1999 
2000 static const struct got_error *
2001 status_new(void *arg, struct dirent *de, const char *parent_path)
2002 {
2003 	const struct got_error *err = NULL;
2004 	struct diff_dir_cb_arg *a = arg;
2005 	char *path = NULL;
2006 
2007 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2008 		return got_error(GOT_ERR_CANCELLED);
2009 
2010 	if (de->d_type == DT_DIR)
2011 		return NULL;
2012 
2013 	/* XXX ignore symlinks for now */
2014 	if (de->d_type == DT_LNK)
2015 		return NULL;
2016 
2017 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
2018 		return NULL;
2019 
2020 	if (parent_path[0]) {
2021 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
2022 			return got_error_from_errno("asprintf");
2023 	} else {
2024 		path = de->d_name;
2025 	}
2026 
2027 	err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED, path,
2028 	    NULL, NULL);
2029 	if (parent_path[0])
2030 		free(path);
2031 	return err;
2032 }
2033 
2034 const struct got_error *
2035 got_worktree_status(struct got_worktree *worktree, const char *path,
2036     struct got_repository *repo, got_worktree_status_cb status_cb,
2037     void *status_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2038 {
2039 	const struct got_error *err = NULL;
2040 	DIR *workdir = NULL;
2041 	char *fileindex_path = NULL;
2042 	struct got_fileindex *fileindex = NULL;
2043 	FILE *index = NULL;
2044 	struct got_fileindex_diff_dir_cb fdiff_cb;
2045 	struct diff_dir_cb_arg arg;
2046 	char *ondisk_path = NULL;
2047 
2048 	fileindex = got_fileindex_alloc();
2049 	if (fileindex == NULL) {
2050 		err = got_error_from_errno("got_fileindex_alloc");
2051 		goto done;
2052 	}
2053 
2054 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2055 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2056 		err = got_error_from_errno("asprintf");
2057 		fileindex_path = NULL;
2058 		goto done;
2059 	}
2060 
2061 	index = fopen(fileindex_path, "rb");
2062 	if (index == NULL) {
2063 		if (errno != ENOENT) {
2064 			err = got_error_from_errno2("fopen", fileindex_path);
2065 			goto done;
2066 		}
2067 	} else {
2068 		err = got_fileindex_read(fileindex, index);
2069 		fclose(index);
2070 		if (err)
2071 			goto done;
2072 	}
2073 
2074 	if (asprintf(&ondisk_path, "%s%s%s",
2075 	    worktree->root_path, path[0] ? "/" : "", path) == -1) {
2076 		err = got_error_from_errno("asprintf");
2077 		goto done;
2078 	}
2079 	workdir = opendir(ondisk_path);
2080 	if (workdir == NULL) {
2081 		if (errno == ENOTDIR || errno == ENOENT) {
2082 			struct got_fileindex_entry *ie;
2083 			ie = got_fileindex_entry_get(fileindex, path);
2084 			if (ie == NULL) {
2085 				err = got_error(GOT_ERR_BAD_PATH);
2086 				goto done;
2087 			}
2088 			err = report_file_status(ie, ondisk_path,
2089 			    status_cb, status_arg, repo);
2090 			goto done;
2091 		} else {
2092 			err = got_error_from_errno2("opendir", ondisk_path);
2093 			goto done;
2094 		}
2095 	}
2096 	fdiff_cb.diff_old_new = status_old_new;
2097 	fdiff_cb.diff_old = status_old;
2098 	fdiff_cb.diff_new = status_new;
2099 	arg.fileindex = fileindex;
2100 	arg.worktree = worktree;
2101 	arg.status_path = path;
2102 	arg.status_path_len = strlen(path);
2103 	arg.repo = repo;
2104 	arg.status_cb = status_cb;
2105 	arg.status_arg = status_arg;
2106 	arg.cancel_cb = cancel_cb;
2107 	arg.cancel_arg = cancel_arg;
2108 	err = got_fileindex_diff_dir(fileindex, workdir, worktree->root_path,
2109 	    path, repo, &fdiff_cb, &arg);
2110 done:
2111 	if (workdir)
2112 		closedir(workdir);
2113 	free(ondisk_path);
2114 	free(fileindex_path);
2115 	got_fileindex_free(fileindex);
2116 	return err;
2117 }
2118 
2119 const struct got_error *
2120 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
2121     const char *arg)
2122 {
2123 	const struct got_error *err = NULL;
2124 	char *resolved, *path = NULL;
2125 	size_t len;
2126 
2127 	*wt_path = NULL;
2128 
2129 	resolved = realpath(arg, NULL);
2130 	if (resolved == NULL)
2131 		return got_error_from_errno2("realpath", arg);
2132 
2133 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
2134 	    strlen(got_worktree_get_root_path(worktree)))) {
2135 		err = got_error(GOT_ERR_BAD_PATH);
2136 		goto done;
2137 	}
2138 
2139 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
2140 		err = got_path_skip_common_ancestor(&path,
2141 		    got_worktree_get_root_path(worktree), resolved);
2142 		if (err)
2143 			goto done;
2144 	} else {
2145 		path = strdup("");
2146 		if (path == NULL) {
2147 			err = got_error_from_errno("strdup");
2148 			goto done;
2149 		}
2150 	}
2151 
2152 	/* XXX status walk can't deal with trailing slash! */
2153 	len = strlen(path);
2154 	while (path[len - 1] == '/') {
2155 		path[len - 1] = '\0';
2156 		len--;
2157 	}
2158 done:
2159 	free(resolved);
2160 	if (err == NULL)
2161 		*wt_path = path;
2162 	else
2163 		free(path);
2164 	return err;
2165 }
2166 
2167 static const struct got_error *
2168 schedule_addition(const char *ondisk_path, struct got_fileindex *fileindex,
2169     const char *relpath, got_worktree_status_cb status_cb, void *status_arg,
2170     struct got_repository *repo)
2171 {
2172 	const struct got_error *err = NULL;
2173 	struct got_fileindex_entry *ie;
2174 
2175 	/* Re-adding an existing entry is a no-op. */
2176 	if (got_fileindex_entry_get(fileindex, relpath) != NULL)
2177 		return NULL;
2178 
2179 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
2180 	if (err)
2181 		return err;
2182 
2183 	err = got_fileindex_entry_add(fileindex, ie);
2184 	if (err) {
2185 		got_fileindex_entry_free(ie);
2186 		return err;
2187 	}
2188 
2189 	return report_file_status(ie, relpath, status_cb, status_arg, repo);
2190 }
2191 
2192 const struct got_error *
2193 got_worktree_schedule_add(struct got_worktree *worktree,
2194     struct got_pathlist_head *ondisk_paths,
2195     got_worktree_status_cb status_cb, void *status_arg,
2196     struct got_repository *repo)
2197 {
2198 	struct got_fileindex *fileindex = NULL;
2199 	char *fileindex_path = NULL;
2200 	FILE *index = NULL;
2201 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2202 	struct got_pathlist_entry *pe;
2203 
2204 	err = lock_worktree(worktree, LOCK_EX);
2205 	if (err)
2206 		return err;
2207 
2208 
2209 	fileindex = got_fileindex_alloc();
2210 	if (fileindex == NULL) {
2211 		err = got_error_from_errno("got_fileindex_alloc");
2212 		goto done;
2213 	}
2214 
2215 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2216 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2217 		err = got_error_from_errno("asprintf");
2218 		fileindex_path = NULL;
2219 		goto done;
2220 	}
2221 
2222 	index = fopen(fileindex_path, "rb");
2223 	if (index == NULL) {
2224 		err = got_error_from_errno2("fopen", fileindex_path);
2225 		goto done;
2226 	}
2227 
2228 	err = got_fileindex_read(fileindex, index);
2229 	if (err)
2230 		goto done;
2231 
2232 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2233 		char *relpath;
2234 		err = got_path_skip_common_ancestor(&relpath,
2235 		    got_worktree_get_root_path(worktree), pe->path);
2236 		if (err)
2237 			break;
2238 		err = schedule_addition(pe->path, fileindex, relpath,
2239 		    status_cb, status_arg, repo);
2240 		free(relpath);
2241 		if (err)
2242 			break;
2243 	}
2244 	sync_err = sync_fileindex(fileindex, fileindex_path);
2245 	if (sync_err && err == NULL)
2246 		err = sync_err;
2247 done:
2248 	if (index) {
2249 		if (fclose(index) != 0 && err == NULL)
2250 			err = got_error_from_errno("fclose");
2251 	}
2252 	if (fileindex)
2253 		got_fileindex_free(fileindex);
2254 	unlockerr = lock_worktree(worktree, LOCK_SH);
2255 	if (unlockerr && err == NULL)
2256 		err = unlockerr;
2257 	return err;
2258 }
2259 
2260 static const struct got_error *
2261 schedule_for_deletion(const char *ondisk_path, struct got_fileindex *fileindex,
2262     const char *relpath, int delete_local_mods,
2263     got_worktree_status_cb status_cb, void *status_arg,
2264     struct got_repository *repo)
2265 {
2266 	const struct got_error *err = NULL;
2267 	struct got_fileindex_entry *ie = NULL;
2268 	unsigned char status;
2269 	struct stat sb;
2270 
2271 	ie = got_fileindex_entry_get(fileindex, relpath);
2272 	if (ie == NULL)
2273 		return got_error(GOT_ERR_BAD_PATH);
2274 
2275 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2276 	if (err)
2277 		return err;
2278 
2279 	if (status != GOT_STATUS_NO_CHANGE) {
2280 		if (status == GOT_STATUS_DELETE)
2281 			return got_error_set_errno(ENOENT, ondisk_path);
2282 		if (status != GOT_STATUS_MODIFY)
2283 			return got_error(GOT_ERR_FILE_STATUS);
2284 		if (!delete_local_mods)
2285 			return got_error(GOT_ERR_FILE_MODIFIED);
2286 	}
2287 
2288 	if (unlink(ondisk_path) != 0)
2289 		return got_error_from_errno2("unlink", ondisk_path);
2290 
2291 	got_fileindex_entry_mark_deleted_from_disk(ie);
2292 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2293 }
2294 
2295 const struct got_error *
2296 got_worktree_schedule_delete(struct got_worktree *worktree,
2297     struct got_pathlist_head *ondisk_paths, int delete_local_mods,
2298     got_worktree_status_cb status_cb, void *status_arg,
2299     struct got_repository *repo)
2300 {
2301 	struct got_fileindex *fileindex = NULL;
2302 	char *fileindex_path = NULL;
2303 	FILE *index = NULL;
2304 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2305 	struct got_pathlist_entry *pe;
2306 
2307 	err = lock_worktree(worktree, LOCK_EX);
2308 	if (err)
2309 		return err;
2310 
2311 	fileindex = got_fileindex_alloc();
2312 	if (fileindex == NULL) {
2313 		err = got_error_from_errno("got_fileindex_alloc");
2314 		goto done;
2315 	}
2316 
2317 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2318 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2319 		err = got_error_from_errno("asprintf");
2320 		fileindex_path = NULL;
2321 		goto done;
2322 	}
2323 
2324 	index = fopen(fileindex_path, "rb");
2325 	if (index == NULL) {
2326 		err = got_error_from_errno2("fopen", fileindex_path);
2327 		goto done;
2328 	}
2329 
2330 	err = got_fileindex_read(fileindex, index);
2331 	if (err)
2332 		goto done;
2333 
2334 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2335 		char *relpath;
2336 		err = got_path_skip_common_ancestor(&relpath,
2337 		    got_worktree_get_root_path(worktree), pe->path);
2338 		if (err)
2339 			break;
2340 		err = schedule_for_deletion(pe->path, fileindex, relpath,
2341 		    delete_local_mods, status_cb, status_arg, repo);
2342 		free(relpath);
2343 		if (err)
2344 			break;
2345 	}
2346 	sync_err = sync_fileindex(fileindex, fileindex_path);
2347 	if (sync_err && err == NULL)
2348 		err = sync_err;
2349 done:
2350 	if (index) {
2351 		if (fclose(index) != 0 && err == NULL)
2352 			err = got_error_from_errno("fclose");
2353 	}
2354 	if (fileindex)
2355 		got_fileindex_free(fileindex);
2356 	unlockerr = lock_worktree(worktree, LOCK_SH);
2357 	if (unlockerr && err == NULL)
2358 		err = unlockerr;
2359 	return err;
2360 }
2361 
2362 static const struct got_error *
2363 revert_file(struct got_worktree *worktree, struct got_fileindex *fileindex,
2364     const char *ondisk_path,
2365     got_worktree_checkout_cb progress_cb, void *progress_arg,
2366     struct got_repository *repo)
2367 {
2368 	const struct got_error *err = NULL;
2369 	char *relpath = NULL, *parent_path = NULL;
2370 	struct got_fileindex_entry *ie;
2371 	struct got_tree_object *tree = NULL;
2372 	struct got_object_id *tree_id = NULL;
2373 	const struct got_tree_entry *te;
2374 	char *tree_path = NULL, *te_name;
2375 	struct got_blob_object *blob = NULL;
2376 	unsigned char status;
2377 	struct stat sb;
2378 
2379 	err = got_path_skip_common_ancestor(&relpath,
2380 	    got_worktree_get_root_path(worktree), ondisk_path);
2381 	if (err)
2382 		goto done;
2383 
2384 	ie = got_fileindex_entry_get(fileindex, relpath);
2385 	if (ie == NULL) {
2386 		err = got_error(GOT_ERR_BAD_PATH);
2387 		goto done;
2388 	}
2389 
2390 	/* Construct in-repository path of tree which contains this blob. */
2391 	err = got_path_dirname(&parent_path, ie->path);
2392 	if (err) {
2393 		if (err->code != GOT_ERR_BAD_PATH)
2394 			goto done;
2395 		parent_path = strdup("/");
2396 		if (parent_path == NULL) {
2397 			err = got_error_from_errno("strdup");
2398 			goto done;
2399 		}
2400 	}
2401 	if (got_path_is_root_dir(worktree->path_prefix)) {
2402 		tree_path = strdup(parent_path);
2403 		if (tree_path == NULL) {
2404 			err = got_error_from_errno("strdup");
2405 			goto done;
2406 		}
2407 	} else {
2408 		if (got_path_is_root_dir(parent_path)) {
2409 			tree_path = strdup(worktree->path_prefix);
2410 			if (tree_path == NULL) {
2411 				err = got_error_from_errno("strdup");
2412 				goto done;
2413 			}
2414 		} else {
2415 			if (asprintf(&tree_path, "%s/%s",
2416 			    worktree->path_prefix, parent_path) == -1) {
2417 				err = got_error_from_errno("asprintf");
2418 				goto done;
2419 			}
2420 		}
2421 	}
2422 
2423 	err = got_object_id_by_path(&tree_id, repo, worktree->base_commit_id,
2424 	    tree_path);
2425 	if (err)
2426 		goto done;
2427 
2428 	err = got_object_open_as_tree(&tree, repo, tree_id);
2429 	if (err)
2430 		goto done;
2431 
2432 	te_name = basename(ie->path);
2433 	if (te_name == NULL) {
2434 		err = got_error_from_errno2("basename", ie->path);
2435 		goto done;
2436 	}
2437 
2438 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2439 	if (err)
2440 		goto done;
2441 
2442 	te = got_object_tree_find_entry(tree, te_name);
2443 	if (te == NULL && status != GOT_STATUS_ADD) {
2444 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
2445 		goto done;
2446 	}
2447 
2448 	switch (status) {
2449 	case GOT_STATUS_ADD:
2450 		(*progress_cb)(progress_arg, GOT_STATUS_REVERT, ie->path);
2451 		got_fileindex_entry_remove(fileindex, ie);
2452 		break;
2453 	case GOT_STATUS_DELETE:
2454 	case GOT_STATUS_MODIFY:
2455 	case GOT_STATUS_CONFLICT:
2456 	case GOT_STATUS_MISSING: {
2457 		struct got_object_id id;
2458 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2459 		err = got_object_open_as_blob(&blob, repo, &id, 8192);
2460 		if (err)
2461 			goto done;
2462 		err = install_blob(worktree, ondisk_path, ie->path,
2463 		    te->mode, sb.st_mode, blob, 0, 1, repo, progress_cb,
2464 		    progress_arg);
2465 		if (err)
2466 			goto done;
2467 		if (status == GOT_STATUS_DELETE) {
2468 			err = update_blob_fileindex_entry(worktree,
2469 			    fileindex, ie, ondisk_path, ie->path, blob, 1);
2470 			if (err)
2471 				goto done;
2472 		}
2473 		break;
2474 	}
2475 	default:
2476 			goto done;
2477 	}
2478 done:
2479 	free(relpath);
2480 	free(parent_path);
2481 	free(tree_path);
2482 	if (blob)
2483 		got_object_blob_close(blob);
2484 	if (tree)
2485 		got_object_tree_close(tree);
2486 	free(tree_id);
2487 	return err;
2488 }
2489 
2490 const struct got_error *
2491 got_worktree_revert(struct got_worktree *worktree,
2492     struct got_pathlist_head *ondisk_paths,
2493     got_worktree_checkout_cb progress_cb, void *progress_arg,
2494     struct got_repository *repo)
2495 {
2496 	struct got_fileindex *fileindex = NULL;
2497 	char *fileindex_path = NULL;
2498 	FILE *index = NULL;
2499 	const struct got_error *err = NULL, *unlockerr = NULL;
2500 	const struct got_error *sync_err = NULL;
2501 	struct got_pathlist_entry *pe;
2502 
2503 	err = lock_worktree(worktree, LOCK_EX);
2504 	if (err)
2505 		return err;
2506 
2507 	fileindex = got_fileindex_alloc();
2508 	if (fileindex == NULL) {
2509 		err = got_error_from_errno("got_fileindex_alloc");
2510 		goto done;
2511 	}
2512 
2513 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2514 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2515 		err = got_error_from_errno("asprintf");
2516 		fileindex_path = NULL;
2517 		goto done;
2518 	}
2519 
2520 	index = fopen(fileindex_path, "rb");
2521 	if (index == NULL) {
2522 		err = got_error_from_errno2("fopen", fileindex_path);
2523 		goto done;
2524 	}
2525 
2526 	err = got_fileindex_read(fileindex, index);
2527 	if (err)
2528 		goto done;
2529 
2530 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2531 		err = revert_file(worktree, fileindex, pe->path,
2532 		    progress_cb, progress_arg, repo);
2533 		if (err)
2534 			break;
2535 	}
2536 	sync_err = sync_fileindex(fileindex, fileindex_path);
2537 	if (sync_err && err == NULL)
2538 		err = sync_err;
2539 done:
2540 	if (index) {
2541 		if (fclose(index) != 0 && err == NULL)
2542 			err = got_error_from_errno("fclose");
2543 	}
2544 	if (fileindex)
2545 		got_fileindex_free(fileindex);
2546 	unlockerr = lock_worktree(worktree, LOCK_SH);
2547 	if (unlockerr && err == NULL)
2548 		err = unlockerr;
2549 	return err;
2550 }
2551 
2552 static void
2553 free_commitable(struct got_commitable *ct)
2554 {
2555 	free(ct->path);
2556 	free(ct->in_repo_path);
2557 	free(ct->ondisk_path);
2558 	free(ct->blob_id);
2559 	free(ct->base_blob_id);
2560 	free(ct->base_commit_id);
2561 	free(ct);
2562 }
2563 
2564 struct collect_commitables_arg {
2565 	struct got_pathlist_head *commitable_paths;
2566 	struct got_repository *repo;
2567 	struct got_worktree *worktree;
2568 };
2569 
2570 static const struct got_error *
2571 collect_commitables(void *arg, unsigned char status, const char *relpath,
2572     struct got_object_id *blob_id, struct got_object_id *commit_id)
2573 {
2574 	struct collect_commitables_arg *a = arg;
2575 	const struct got_error *err = NULL;
2576 	struct got_commitable *ct = NULL;
2577 	struct got_pathlist_entry *new = NULL;
2578 	char *parent_path = NULL, *path = NULL;
2579 	struct stat sb;
2580 
2581 	if (status == GOT_STATUS_CONFLICT)
2582 		return got_error(GOT_ERR_COMMIT_CONFLICT);
2583 
2584 	if (status != GOT_STATUS_MODIFY && status != GOT_STATUS_ADD &&
2585 	    status != GOT_STATUS_DELETE)
2586 		return NULL;
2587 
2588 	if (asprintf(&path, "/%s", relpath) == -1) {
2589 		err = got_error_from_errno("asprintf");
2590 		goto done;
2591 	}
2592 	if (strcmp(path, "/") == 0) {
2593 		parent_path = strdup("");
2594 		if (parent_path == NULL)
2595 			return got_error_from_errno("strdup");
2596 	} else {
2597 		err = got_path_dirname(&parent_path, path);
2598 		if (err)
2599 			return err;
2600 	}
2601 
2602 	ct = calloc(1, sizeof(*ct));
2603 	if (ct == NULL) {
2604 		err = got_error_from_errno("calloc");
2605 		goto done;
2606 	}
2607 
2608 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
2609 	    relpath) == -1) {
2610 		err = got_error_from_errno("asprintf");
2611 		goto done;
2612 	}
2613 	if (status == GOT_STATUS_DELETE) {
2614 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
2615 	} else {
2616 		if (lstat(ct->ondisk_path, &sb) != 0) {
2617 			err = got_error_from_errno2("lstat", ct->ondisk_path);
2618 			goto done;
2619 		}
2620 		ct->mode = sb.st_mode;
2621 	}
2622 
2623 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
2624 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
2625 	    relpath) == -1) {
2626 		err = got_error_from_errno("asprintf");
2627 		goto done;
2628 	}
2629 
2630 	ct->status = status;
2631 	ct->blob_id = NULL; /* will be filled in when blob gets created */
2632 	if (ct->status != GOT_STATUS_ADD) {
2633 		ct->base_blob_id = got_object_id_dup(blob_id);
2634 		if (ct->base_blob_id == NULL) {
2635 			err = got_error_from_errno("got_object_id_dup");
2636 			goto done;
2637 		}
2638 		ct->base_commit_id = got_object_id_dup(commit_id);
2639 		if (ct->base_commit_id == NULL) {
2640 			err = got_error_from_errno("got_object_id_dup");
2641 			goto done;
2642 		}
2643 	}
2644 	ct->path = strdup(path);
2645 	if (ct->path == NULL) {
2646 		err = got_error_from_errno("strdup");
2647 		goto done;
2648 	}
2649 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
2650 done:
2651 	if (ct && (err || new == NULL))
2652 		free_commitable(ct);
2653 	free(parent_path);
2654 	free(path);
2655 	return err;
2656 }
2657 
2658 static const struct got_error *write_tree(struct got_object_id **,
2659     struct got_tree_object *, const char *, struct got_pathlist_head *,
2660     got_worktree_status_cb status_cb, void *status_arg,
2661     struct got_repository *);
2662 
2663 static const struct got_error *
2664 write_subtree(struct got_object_id **new_subtree_id,
2665     struct got_tree_entry *te, const char *parent_path,
2666     struct got_pathlist_head *commitable_paths,
2667     got_worktree_status_cb status_cb, void *status_arg,
2668     struct got_repository *repo)
2669 {
2670 	const struct got_error *err = NULL;
2671 	struct got_tree_object *subtree;
2672 	char *subpath;
2673 
2674 	if (asprintf(&subpath, "%s%s%s", parent_path,
2675 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
2676 		return got_error_from_errno("asprintf");
2677 
2678 	err = got_object_open_as_tree(&subtree, repo, te->id);
2679 	if (err)
2680 		return err;
2681 
2682 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
2683 	    status_cb, status_arg, repo);
2684 	got_object_tree_close(subtree);
2685 	free(subpath);
2686 	return err;
2687 }
2688 
2689 static const struct got_error *
2690 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
2691 {
2692 	const struct got_error *err = NULL;
2693 	char *ct_parent_path = NULL;
2694 
2695 	*match = 0;
2696 
2697 	if (strchr(ct->path, '/') == NULL) {
2698 		*match = got_path_is_root_dir(path);
2699 		return NULL;
2700 	}
2701 
2702 	err = got_path_dirname(&ct_parent_path, ct->path);
2703 	if (err)
2704 		return err;
2705 	*match = (strcmp(path, ct_parent_path) == 0);
2706 	free(ct_parent_path);
2707 	return err;
2708 }
2709 
2710 static mode_t
2711 get_ct_file_mode(struct got_commitable *ct)
2712 {
2713 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
2714 }
2715 
2716 static const struct got_error *
2717 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
2718     struct got_tree_entry *te, struct got_commitable *ct)
2719 {
2720 	const struct got_error *err = NULL;
2721 
2722 	*new_te = NULL;
2723 
2724 	err = got_object_tree_entry_dup(new_te, te);
2725 	if (err)
2726 		goto done;
2727 
2728 	(*new_te)->mode = get_ct_file_mode(ct);
2729 
2730 	free((*new_te)->id);
2731 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2732 	if ((*new_te)->id == NULL) {
2733 		err = got_error_from_errno("got_object_id_dup");
2734 		goto done;
2735 	}
2736 done:
2737 	if (err && *new_te) {
2738 		got_object_tree_entry_close(*new_te);
2739 		*new_te = NULL;
2740 	}
2741 	return err;
2742 }
2743 
2744 static const struct got_error *
2745 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
2746     struct got_commitable *ct)
2747 {
2748 	const struct got_error *err = NULL;
2749 	char *ct_name;
2750 
2751 	 *new_te = NULL;
2752 
2753 	*new_te = calloc(1, sizeof(**new_te));
2754 	if (*new_te == NULL)
2755 		return got_error_from_errno("calloc");
2756 
2757 	ct_name = basename(ct->path);
2758 	if (ct_name == NULL) {
2759 		err = got_error_from_errno2("basename", ct->path);
2760 		goto done;
2761 	}
2762 	(*new_te)->name = strdup(ct_name);
2763 	if ((*new_te)->name == NULL) {
2764 		err = got_error_from_errno("strdup");
2765 		goto done;
2766 	}
2767 
2768 	(*new_te)->mode = get_ct_file_mode(ct);
2769 
2770 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2771 	if ((*new_te)->id == NULL) {
2772 		err = got_error_from_errno("got_object_id_dup");
2773 		goto done;
2774 	}
2775 done:
2776 	if (err && *new_te) {
2777 		got_object_tree_entry_close(*new_te);
2778 		*new_te = NULL;
2779 	}
2780 	return err;
2781 }
2782 
2783 static const struct got_error *
2784 insert_tree_entry(struct got_tree_entry *new_te,
2785     struct got_pathlist_head *paths)
2786 {
2787 	const struct got_error *err = NULL;
2788 	struct got_pathlist_entry *new_pe;
2789 
2790 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
2791 	if (err)
2792 		return err;
2793 	if (new_pe == NULL)
2794 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
2795 	return NULL;
2796 }
2797 
2798 static const struct got_error *
2799 report_ct_status(struct got_commitable *ct,
2800     got_worktree_status_cb status_cb, void *status_arg)
2801 {
2802 	const char *ct_path = ct->path;
2803 	while (ct_path[0] == '/')
2804 		ct_path++;
2805 	return (*status_cb)(status_arg, ct->status, ct_path, ct->blob_id, NULL);
2806 }
2807 
2808 static const struct got_error *
2809 match_modified_subtree(int *modified, struct got_tree_entry *te,
2810     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
2811 {
2812 	const struct got_error *err = NULL;
2813 	struct got_pathlist_entry *pe;
2814 	char *te_path;
2815 
2816 	*modified = 0;
2817 
2818 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
2819 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
2820 	    te->name) == -1)
2821 		return got_error_from_errno("asprintf");
2822 
2823 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2824 		struct got_commitable *ct = pe->data;
2825 		*modified = got_path_is_child(ct->in_repo_path, te_path,
2826 		    strlen(te_path));
2827 		 if (*modified)
2828 			break;
2829 	}
2830 
2831 	free(te_path);
2832 	return err;
2833 }
2834 
2835 static const struct got_error *
2836 match_deleted_or_modified_ct(struct got_commitable **ctp,
2837     struct got_tree_entry *te, const char *base_tree_path,
2838     struct got_pathlist_head *commitable_paths)
2839 {
2840 	const struct got_error *err = NULL;
2841 	struct got_pathlist_entry *pe;
2842 
2843 	*ctp = NULL;
2844 
2845 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2846 		struct got_commitable *ct = pe->data;
2847 		char *ct_name = NULL;
2848 		int path_matches;
2849 
2850 		if (ct->status != GOT_STATUS_MODIFY &&
2851 		    ct->status != GOT_STATUS_DELETE)
2852 			continue;
2853 
2854 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
2855 			continue;
2856 
2857 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
2858 		 if (err)
2859 			return err;
2860 		if (!path_matches)
2861 			continue;
2862 
2863 		ct_name = basename(pe->path);
2864 		if (ct_name == NULL)
2865 			return got_error_from_errno2("basename", pe->path);
2866 
2867 		if (strcmp(te->name, ct_name) != 0)
2868 			continue;
2869 
2870 		*ctp = ct;
2871 		break;
2872 	}
2873 
2874 	return err;
2875 }
2876 
2877 static const struct got_error *
2878 write_tree(struct got_object_id **new_tree_id,
2879     struct got_tree_object *base_tree, const char *path_base_tree,
2880     struct got_pathlist_head *commitable_paths,
2881     got_worktree_status_cb status_cb, void *status_arg,
2882     struct got_repository *repo)
2883 {
2884 	const struct got_error *err = NULL;
2885 	const struct got_tree_entries *base_entries = NULL;
2886 	struct got_pathlist_head paths;
2887 	struct got_tree_entries new_tree_entries;
2888 	struct got_tree_entry *te, *new_te = NULL;
2889 	struct got_pathlist_entry *pe;
2890 
2891 	TAILQ_INIT(&paths);
2892 	new_tree_entries.nentries = 0;
2893 	SIMPLEQ_INIT(&new_tree_entries.head);
2894 
2895 	/* Insert, and recurse into, newly added entries first. */
2896 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2897 		struct got_commitable *ct = pe->data;
2898 		char *child_path = NULL, *slash;
2899 
2900 		if (ct->status != GOT_STATUS_ADD ||
2901 		    (ct->flags & GOT_COMMITABLE_ADDED))
2902 			continue;
2903 
2904 		 if (!got_path_is_child(pe->path, path_base_tree,
2905 		     strlen(path_base_tree)))
2906 			continue;
2907 
2908 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
2909 		    pe->path);
2910 		if (err)
2911 			goto done;
2912 
2913 		slash = strchr(child_path, '/');
2914 		if (slash == NULL) {
2915 			err = alloc_added_blob_tree_entry(&new_te, ct);
2916 			if (err)
2917 				goto done;
2918 			err = report_ct_status(ct, status_cb, status_arg);
2919 			if (err)
2920 				goto done;
2921 			ct->flags |= GOT_COMMITABLE_ADDED;
2922 		} else {
2923 			char *subtree_path;
2924 
2925 			*slash = '\0'; /* trim trailing path components */
2926 			if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
2927 			    got_path_is_root_dir(path_base_tree) ? "" : "/",
2928 			    child_path) == -1) {
2929 				err = got_error_from_errno("asprintf");
2930 				goto done;
2931 			}
2932 
2933 			new_te = calloc(1, sizeof(*new_te));
2934 			new_te->mode = S_IFDIR;
2935 			new_te->name = strdup(child_path);
2936 			if (new_te->name == NULL) {
2937 				err = got_error_from_errno("strdup");
2938 				got_object_tree_entry_close(new_te);
2939 				new_te = NULL;
2940 				goto done;
2941 			}
2942 			err = write_tree(&new_te->id, NULL, subtree_path,
2943 			    commitable_paths, status_cb, status_arg, repo);
2944 			free(subtree_path);
2945 			if (err) {
2946 				got_object_tree_entry_close(new_te);
2947 				new_te = NULL;
2948 				goto done;
2949 			}
2950 		}
2951 		err = insert_tree_entry(new_te, &paths);
2952 		if (err)
2953 			goto done;
2954 	}
2955 
2956 	if (base_tree) {
2957 		/* Handle modified and deleted entries. */
2958 		base_entries = got_object_tree_get_entries(base_tree);
2959 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
2960 			struct got_commitable *ct = NULL;
2961 
2962 			if (S_ISDIR(te->mode)) {
2963 				int modified;
2964 				err = got_object_tree_entry_dup(&new_te, te);
2965 				if (err)
2966 					goto done;
2967 				err = match_modified_subtree(&modified, te,
2968 				    path_base_tree, commitable_paths);
2969 				if (err)
2970 					goto done;
2971 				/* Avoid recursion into unmodified subtrees. */
2972 				if (modified) {
2973 					free(new_te->id);
2974 					err = write_subtree(&new_te->id, te,
2975 					    path_base_tree, commitable_paths,
2976 					    status_cb, status_arg, repo);
2977 					if (err)
2978 						goto done;
2979 				}
2980 				err = insert_tree_entry(new_te, &paths);
2981 				if (err)
2982 					goto done;
2983 				continue;
2984 			}
2985 
2986 			err = match_deleted_or_modified_ct(&ct, te,
2987 			    path_base_tree, commitable_paths);
2988 			if (ct) {
2989 				/* NB: Deleted entries get dropped here. */
2990 				if (ct->status == GOT_STATUS_MODIFY) {
2991 					err = alloc_modified_blob_tree_entry(
2992 					    &new_te, te, ct);
2993 					if (err)
2994 						goto done;
2995 					err = insert_tree_entry(new_te, &paths);
2996 					if (err)
2997 						goto done;
2998 				}
2999 				err = report_ct_status(ct, status_cb,
3000 				    status_arg);
3001 				if (err)
3002 					goto done;
3003 			} else {
3004 				/* Entry is unchanged; just copy it. */
3005 				err = got_object_tree_entry_dup(&new_te, te);
3006 				if (err)
3007 					goto done;
3008 				err = insert_tree_entry(new_te, &paths);
3009 				if (err)
3010 					goto done;
3011 			}
3012 		}
3013 	}
3014 
3015 	/* Write new list of entries; deleted entries have been dropped. */
3016 	TAILQ_FOREACH(pe, &paths, entry) {
3017 		struct got_tree_entry *te = pe->data;
3018 		new_tree_entries.nentries++;
3019 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
3020 	}
3021 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
3022 done:
3023 	got_object_tree_entries_close(&new_tree_entries);
3024 	got_pathlist_free(&paths);
3025 	return err;
3026 }
3027 
3028 static const struct got_error *
3029 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
3030     struct got_object_id *new_base_commit_id, struct got_worktree *worktree)
3031 {
3032 	const struct got_error *err = NULL, *sync_err;
3033 	char *fileindex_path = NULL;
3034 	struct got_fileindex *fileindex = NULL;
3035 	struct got_pathlist_entry *pe;
3036 
3037 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3038 	if (err)
3039 		return err;
3040 
3041 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3042 		struct got_fileindex_entry *ie;
3043 		struct got_commitable *ct = pe->data;
3044 
3045 		ie = got_fileindex_entry_get(fileindex, pe->path);
3046 		if (ie) {
3047 			if (ct->status == GOT_STATUS_DELETE) {
3048 				got_fileindex_entry_remove(fileindex, ie);
3049 				got_fileindex_entry_free(ie);
3050 			} else
3051 				err = got_fileindex_entry_update(ie,
3052 				    ct->ondisk_path, ct->blob_id->sha1,
3053 				    new_base_commit_id->sha1, 1);
3054 		} else {
3055 			err = got_fileindex_entry_alloc(&ie,
3056 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
3057 			    new_base_commit_id->sha1);
3058 			if (err)
3059 				break;
3060 			err = got_fileindex_entry_add(fileindex, ie);
3061 			if (err)
3062 				break;
3063 		}
3064 	}
3065 	sync_err = sync_fileindex(fileindex, fileindex_path);
3066 	if (sync_err && err == NULL)
3067 		err = sync_err;
3068 	free(fileindex_path);
3069 	got_fileindex_free(fileindex);
3070 	return err;
3071 }
3072 
3073 static const struct got_error *
3074 check_ct_out_of_date(struct got_commitable *ct, struct got_repository *repo,
3075 	struct got_object_id *head_commit_id)
3076 {
3077 	const struct got_error *err = NULL;
3078 	struct got_object_id *id_in_head = NULL, *id = NULL;
3079 	struct got_commit_object *commit = NULL;
3080 	char *path = NULL;
3081 	const char *ct_path = ct->in_repo_path;
3082 
3083 	while (ct_path[0] == '/')
3084 		ct_path++;
3085 
3086 	/*
3087 	 * Ensure that no modifications were made to files *and their parents*
3088 	 * in commits between the file's base commit and the branch head.
3089 	 *
3090 	 * Checking the parents is important for detecting conflicting tree
3091 	 * configurations (files or parent folders might have been moved,
3092 	 * deleted, added again, etc.). Such changes need to be merged with
3093 	 * local changes before a commit can occur.
3094 	 *
3095 	 * The implication is that the file's (parent) entry in the root
3096 	 * directory must have the same ID in all relevant commits.
3097 	 */
3098 	if (ct->status != GOT_STATUS_ADD) {
3099 		struct got_object_qid *pid;
3100 		char *slash;
3101 		struct got_object_id *root_entry_id = NULL;
3102 
3103 		/* Trivial case: base commit == head commit */
3104 		if (got_object_id_cmp(ct->base_commit_id, head_commit_id) == 0)
3105 			return NULL;
3106 
3107 		/* Compute the path to the root directory's entry. */
3108 		path = strdup(ct_path);
3109 		if (path == NULL) {
3110 			err = got_error_from_errno("strdup");
3111 			goto done;
3112 		}
3113 		slash = strchr(path, '/');
3114 		if (slash)
3115 			*slash = '\0';
3116 
3117 		err = got_object_open_as_commit(&commit, repo, head_commit_id);
3118 		if (err)
3119 			goto done;
3120 
3121 		err = got_object_id_by_path(&root_entry_id, repo,
3122 		    head_commit_id, path);
3123 		if (err)
3124 			goto done;
3125 
3126 		pid = SIMPLEQ_FIRST(got_object_commit_get_parent_ids(commit));
3127 		while (pid) {
3128 			struct got_commit_object *pcommit;
3129 
3130 			err = got_object_id_by_path(&id, repo, pid->id, path);
3131 			if (err) {
3132 				if (err->code != GOT_ERR_NO_TREE_ENTRY)
3133 					goto done;
3134 				err = NULL;
3135 				break;
3136 			}
3137 
3138 			err = got_object_id_by_path(&id, repo, pid->id, path);
3139 			if (err)
3140 				goto done;
3141 
3142 			if (got_object_id_cmp(id, root_entry_id) != 0) {
3143 				err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3144 				break;
3145 			}
3146 
3147 			if (got_object_id_cmp(pid->id, ct->base_commit_id) == 0)
3148 				break; /* all relevant commits scanned */
3149 
3150 			err = got_object_open_as_commit(&pcommit, repo,
3151 			    pid->id);
3152 			if (err)
3153 				goto done;
3154 
3155 			got_object_commit_close(commit);
3156 			commit = pcommit;
3157 			pid = SIMPLEQ_FIRST(got_object_commit_get_parent_ids(
3158 			    commit));
3159 		}
3160 	} else {
3161 		/* Require that added files don't exist in the branch head. */
3162 		err = got_object_id_by_path(&id_in_head, repo, head_commit_id,
3163 		    ct_path);
3164 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3165 			goto done;
3166 		err = id_in_head ? got_error(GOT_ERR_COMMIT_OUT_OF_DATE) : NULL;
3167 	}
3168 done:
3169 	if (commit)
3170 		got_object_commit_close(commit);
3171 	free(id_in_head);
3172 	free(id);
3173 	free(path);
3174 	return err;
3175 }
3176 
3177 const struct got_error *
3178 got_worktree_commit(struct got_object_id **new_commit_id,
3179     struct got_worktree *worktree, const char *ondisk_path,
3180     const char *author, const char *committer,
3181     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3182     got_worktree_status_cb status_cb, void *status_arg,
3183     struct got_repository *repo)
3184 {
3185 	const struct got_error *err = NULL, *unlockerr = NULL;
3186 	struct collect_commitables_arg cc_arg;
3187 	struct got_pathlist_head commitable_paths;
3188 	struct got_pathlist_entry *pe;
3189 	char *relpath = NULL;
3190 	const char *head_ref_name = NULL;
3191 	struct got_reference *head_ref = NULL;
3192 	struct got_commit_object *head_commit = NULL;
3193 	struct got_object_id *head_commit_id = NULL;
3194 	struct got_reference *head_ref2 = NULL;
3195 	struct got_object_id *head_commit_id2 = NULL;
3196 	struct got_tree_object *head_tree = NULL;
3197 	struct got_object_id *new_tree_id = NULL;
3198 	struct got_object_id_queue parent_ids;
3199 	struct got_object_qid *pid = NULL;
3200 	char *logmsg = NULL;
3201 
3202 	*new_commit_id = NULL;
3203 
3204 	TAILQ_INIT(&commitable_paths);
3205 	SIMPLEQ_INIT(&parent_ids);
3206 
3207 	if (ondisk_path) {
3208 		err = got_path_skip_common_ancestor(&relpath,
3209 		    worktree->root_path, ondisk_path);
3210 		if (err)
3211 			return err;
3212 	}
3213 
3214 	err = lock_worktree(worktree, LOCK_EX);
3215 	if (err)
3216 		goto done;
3217 
3218 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
3219 	if (err)
3220 		goto done;
3221 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
3222 	if (err)
3223 		goto done;
3224 
3225 	cc_arg.commitable_paths = &commitable_paths;
3226 	cc_arg.worktree = worktree;
3227 	cc_arg.repo = repo;
3228 	err = got_worktree_status(worktree, relpath ? relpath : "",
3229 	    repo, collect_commitables, &cc_arg, NULL, NULL);
3230 	if (err)
3231 		goto done;
3232 
3233 	if (TAILQ_EMPTY(&commitable_paths)) {
3234 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
3235 		goto done;
3236 	}
3237 
3238 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
3239 	if (err)
3240 		goto done;
3241 
3242 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3243 		struct got_commitable *ct = pe->data;
3244 		err = check_ct_out_of_date(ct, repo, head_commit_id);
3245 		if (err)
3246 			goto done;
3247 	}
3248 
3249 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
3250 	if (err)
3251 		goto done;
3252 
3253 	if (commit_msg_cb != NULL) {
3254 		err = commit_msg_cb(&commitable_paths, &logmsg, commit_arg);
3255 		if (err)
3256 			goto done;
3257 	}
3258 
3259 	if (logmsg == NULL || strlen(logmsg) == 0) {
3260 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
3261 		goto done;
3262 	}
3263 
3264 	/* Create blobs from added and modified files and record their IDs. */
3265 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3266 		struct got_commitable *ct = pe->data;
3267 		char *ondisk_path;
3268 
3269 		if (ct->status != GOT_STATUS_ADD &&
3270 		    ct->status != GOT_STATUS_MODIFY)
3271 			continue;
3272 
3273 		if (asprintf(&ondisk_path, "%s/%s",
3274 		    worktree->root_path, pe->path) == -1) {
3275 			err = got_error_from_errno("asprintf");
3276 			goto done;
3277 		}
3278 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
3279 		free(ondisk_path);
3280 		if (err)
3281 			goto done;
3282 	}
3283 
3284 	/* Recursively write new tree objects. */
3285 	err = write_tree(&new_tree_id, head_tree, "/", &commitable_paths,
3286 	    status_cb, status_arg, repo);
3287 	if (err)
3288 		goto done;
3289 
3290 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
3291 	if (err)
3292 		goto done;
3293 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
3294 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
3295 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
3296 	got_object_qid_free(pid);
3297 	if (logmsg != NULL)
3298 		free(logmsg);
3299 	if (err)
3300 		goto done;
3301 
3302 	/* Check if a concurrent commit to our branch has occurred. */
3303 	head_ref_name = got_worktree_get_head_ref_name(worktree);
3304 	if (head_ref_name == NULL) {
3305 		err = got_error_from_errno("got_worktree_get_head_ref_name");
3306 		goto done;
3307 	}
3308 	/* Lock the reference here to prevent concurrent modification. */
3309 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
3310 	if (err)
3311 		goto done;
3312 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
3313 	if (err)
3314 		goto done;
3315 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
3316 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
3317 		goto done;
3318 	}
3319 	/* Update branch head in repository. */
3320 	err = got_ref_change_ref(head_ref2, *new_commit_id);
3321 	if (err)
3322 		goto done;
3323 	err = got_ref_write(head_ref2, repo);
3324 	if (err)
3325 		goto done;
3326 
3327 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
3328 	if (err)
3329 		goto done;
3330 
3331 	err = ref_base_commit(worktree, repo);
3332 	if (err)
3333 		goto done;
3334 
3335 	err = update_fileindex_after_commit(&commitable_paths,
3336 	    *new_commit_id, worktree);
3337 	if (err)
3338 		goto done;
3339 done:
3340 	unlockerr = lock_worktree(worktree, LOCK_SH);
3341 	if (unlockerr && err == NULL)
3342 		err = unlockerr;
3343 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3344 		struct got_commitable *ct = pe->data;
3345 		free_commitable(ct);
3346 	}
3347 	got_pathlist_free(&commitable_paths);
3348 	if (head_tree)
3349 		got_object_tree_close(head_tree);
3350 	if (head_commit)
3351 		got_object_commit_close(head_commit);
3352 	free(relpath);
3353 	free(head_commit_id);
3354 	free(head_commit_id2);
3355 	if (head_ref)
3356 		got_ref_close(head_ref);
3357 	if (head_ref2) {
3358 		unlockerr = got_ref_unlock(head_ref2);
3359 		if (unlockerr && err == NULL)
3360 			err = unlockerr;
3361 		got_ref_close(head_ref2);
3362 	}
3363 	return err;
3364 }
3365 
3366 const char *
3367 got_commitable_get_path(struct got_commitable *ct)
3368 {
3369 	return ct->path;
3370 }
3371 
3372 unsigned int
3373 got_commitable_get_status(struct got_commitable *ct)
3374 {
3375 	return ct->status;
3376 }