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_worktree.h"
42 #include "got_opentemp.h"
43 
44 #include "got_lib_worktree.h"
45 #include "got_lib_path.h"
46 #include "got_lib_sha1.h"
47 #include "got_lib_fileindex.h"
48 #include "got_lib_inflate.h"
49 #include "got_lib_delta.h"
50 #include "got_lib_object.h"
51 #include "got_lib_object_parse.h"
52 #include "got_lib_object_create.h"
53 #include "got_lib_object_idset.h"
54 #include "got_lib_diff.h"
55 
56 #ifndef MIN
57 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
58 #endif
59 
60 static const struct got_error *
61 create_meta_file(const char *path_got, const char *name, const char *content)
62 {
63 	const struct got_error *err = NULL;
64 	char *path;
65 	int fd = -1;
66 
67 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
68 		err = got_error_from_errno();
69 		path = NULL;
70 		goto done;
71 	}
72 
73 	fd = open(path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
74 	    GOT_DEFAULT_FILE_MODE);
75 	if (fd == -1) {
76 		err = got_error_from_errno();
77 		goto done;
78 	}
79 
80 	if (content) {
81 		int len = dprintf(fd, "%s\n", content);
82 		if (len != strlen(content) + 1) {
83 			err = got_error_from_errno();
84 			goto done;
85 		}
86 	}
87 
88 done:
89 	if (fd != -1 && close(fd) == -1 && err == NULL)
90 		err = got_error_from_errno();
91 	free(path);
92 	return err;
93 }
94 
95 static const struct got_error *
96 update_meta_file(const char *path_got, const char *name, const char *content)
97 {
98 	const struct got_error *err = NULL;
99 	FILE *tmpfile = NULL;
100 	char *tmppath = NULL;
101 	char *path = NULL;
102 
103 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
104 		err = got_error_from_errno();
105 		path = NULL;
106 		goto done;
107 	}
108 
109 	err = got_opentemp_named(&tmppath, &tmpfile, path);
110 	if (err)
111 		goto done;
112 
113 	if (content) {
114 		int len = fprintf(tmpfile, "%s\n", content);
115 		if (len != strlen(content) + 1) {
116 			err = got_error_from_errno();
117 			goto done;
118 		}
119 	}
120 
121 	if (rename(tmppath, path) != 0) {
122 		err = got_error_from_errno();
123 		unlink(tmppath);
124 		goto done;
125 	}
126 
127 done:
128 	free(tmppath);
129 	if (fclose(tmpfile) != 0 && err == NULL)
130 		err = got_error_from_errno();
131 	return err;
132 }
133 
134 static const struct got_error *
135 read_meta_file(char **content, const char *path_got, const char *name)
136 {
137 	const struct got_error *err = NULL;
138 	char *path;
139 	int fd = -1;
140 	ssize_t n;
141 	struct stat sb;
142 
143 	*content = NULL;
144 
145 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
146 		err = got_error_from_errno();
147 		path = NULL;
148 		goto done;
149 	}
150 
151 	fd = open(path, O_RDONLY | O_NOFOLLOW);
152 	if (fd == -1) {
153 		if (errno == ENOENT)
154 			err = got_error(GOT_ERR_WORKTREE_META);
155 		else
156 			err = got_error_from_errno();
157 		goto done;
158 	}
159 	if (flock(fd, LOCK_SH | LOCK_NB) == -1) {
160 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
161 		    : got_error_from_errno());
162 		goto done;
163 	}
164 
165 	if (lstat(path, &sb) != 0) {
166 		err = got_error_from_errno();
167 		goto done;
168 	}
169 	*content = calloc(1, sb.st_size);
170 	if (*content == NULL) {
171 		err = got_error_from_errno();
172 		goto done;
173 	}
174 
175 	n = read(fd, *content, sb.st_size);
176 	if (n != sb.st_size) {
177 		err = (n == -1 ? got_error_from_errno() :
178 		    got_error(GOT_ERR_WORKTREE_META));
179 		goto done;
180 	}
181 	if ((*content)[sb.st_size - 1] != '\n') {
182 		err = got_error(GOT_ERR_WORKTREE_META);
183 		goto done;
184 	}
185 	(*content)[sb.st_size - 1] = '\0';
186 
187 done:
188 	if (fd != -1 && close(fd) == -1 && err == NULL)
189 		err = got_error_from_errno();
190 	free(path);
191 	if (err) {
192 		free(*content);
193 		*content = NULL;
194 	}
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 *refstr = NULL;
209 	char *formatstr = NULL;
210 	char *absprefix = NULL;
211 	char *basestr = NULL;
212 	char *uuidstr = NULL;
213 
214 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
215 		err = got_error(GOT_ERR_WORKTREE_REPO);
216 		goto done;
217 	}
218 
219 	err = got_ref_resolve(&commit_id, repo, head_ref);
220 	if (err)
221 		return err;
222 	err = got_object_get_type(&obj_type, repo, commit_id);
223 	if (err)
224 		return err;
225 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
226 		return got_error(GOT_ERR_OBJ_TYPE);
227 
228 	if (!got_path_is_absolute(prefix)) {
229 		if (asprintf(&absprefix, "/%s", prefix) == -1)
230 			return got_error_from_errno();
231 	}
232 
233 	/* Create top-level directory (may already exist). */
234 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
235 		err = got_error_from_errno();
236 		goto done;
237 	}
238 
239 	/* Create .got directory (may already exist). */
240 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
241 		err = got_error_from_errno();
242 		goto done;
243 	}
244 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
245 		err = got_error_from_errno();
246 		goto done;
247 	}
248 
249 	/* Create an empty lock file. */
250 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
251 	if (err)
252 		goto done;
253 
254 	/* Create an empty file index. */
255 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
256 	if (err)
257 		goto done;
258 
259 	/* Write the HEAD reference. */
260 	refstr = got_ref_to_str(head_ref);
261 	if (refstr == NULL) {
262 		err = got_error_from_errno();
263 		goto done;
264 	}
265 	err = create_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
266 	if (err)
267 		goto done;
268 
269 	/* Record our base commit. */
270 	err = got_object_id_str(&basestr, commit_id);
271 	if (err)
272 		goto done;
273 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
274 	if (err)
275 		goto done;
276 
277 	/* Store path to repository. */
278 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
279 	    got_repo_get_path(repo));
280 	if (err)
281 		goto done;
282 
283 	/* Store in-repository path prefix. */
284 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
285 	    absprefix ? absprefix : prefix);
286 	if (err)
287 		goto done;
288 
289 	/* Generate UUID. */
290 	uuid_create(&uuid, &uuid_status);
291 	if (uuid_status != uuid_s_ok) {
292 		err = got_error_uuid(uuid_status);
293 		goto done;
294 	}
295 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
296 	if (uuid_status != uuid_s_ok) {
297 		err = got_error_uuid(uuid_status);
298 		goto done;
299 	}
300 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
301 	if (err)
302 		goto done;
303 
304 	/* Stamp work tree with format file. */
305 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
306 		err = got_error_from_errno();
307 		goto done;
308 	}
309 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
310 	if (err)
311 		goto done;
312 
313 done:
314 	free(commit_id);
315 	free(path_got);
316 	free(formatstr);
317 	free(refstr);
318 	free(absprefix);
319 	free(basestr);
320 	free(uuidstr);
321 	return err;
322 }
323 
324 static const struct got_error *
325 open_worktree(struct got_worktree **worktree, const char *path)
326 {
327 	const struct got_error *err = NULL;
328 	char *path_got;
329 	char *formatstr = NULL;
330 	char *uuidstr = NULL;
331 	char *path_lock = NULL;
332 	char *base_commit_id_str = NULL;
333 	int version, fd = -1;
334 	const char *errstr;
335 	struct got_repository *repo = NULL;
336 	uint32_t uuid_status;
337 
338 	*worktree = NULL;
339 
340 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
341 		err = got_error_from_errno();
342 		path_got = NULL;
343 		goto done;
344 	}
345 
346 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
347 		err = got_error_from_errno();
348 		path_lock = NULL;
349 		goto done;
350 	}
351 
352 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
353 	if (fd == -1) {
354 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
355 		    : got_error_from_errno());
356 		goto done;
357 	}
358 
359 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
360 	if (err)
361 		goto done;
362 
363 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
364 	if (errstr) {
365 		err = got_error(GOT_ERR_WORKTREE_META);
366 		goto done;
367 	}
368 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
369 		err = got_error(GOT_ERR_WORKTREE_VERS);
370 		goto done;
371 	}
372 
373 	*worktree = calloc(1, sizeof(**worktree));
374 	if (*worktree == NULL) {
375 		err = got_error_from_errno();
376 		goto done;
377 	}
378 	(*worktree)->lockfd = -1;
379 
380 	(*worktree)->root_path = strdup(path);
381 	if ((*worktree)->root_path == NULL) {
382 		err = got_error_from_errno();
383 		goto done;
384 	}
385 	err = read_meta_file(&(*worktree)->repo_path, path_got,
386 	    GOT_WORKTREE_REPOSITORY);
387 	if (err)
388 		goto done;
389 
390 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
391 	    GOT_WORKTREE_PATH_PREFIX);
392 	if (err)
393 		goto done;
394 
395 	err = read_meta_file(&base_commit_id_str, path_got,
396 	    GOT_WORKTREE_BASE_COMMIT);
397 	if (err)
398 		goto done;
399 
400 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
401 	if (err)
402 		goto done;
403 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
404 	if (uuid_status != uuid_s_ok) {
405 		err = got_error_uuid(uuid_status);
406 		goto done;
407 	}
408 
409 	err = got_repo_open(&repo, (*worktree)->repo_path);
410 	if (err)
411 		goto done;
412 
413 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
414 	    base_commit_id_str);
415 	if (err)
416 		goto done;
417 
418 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
419 	    GOT_WORKTREE_HEAD_REF);
420 done:
421 	if (repo)
422 		got_repo_close(repo);
423 	free(path_got);
424 	free(path_lock);
425 	free(base_commit_id_str);
426 	free(uuidstr);
427 	free(formatstr);
428 	if (err) {
429 		if (fd != -1)
430 			close(fd);
431 		if (*worktree != NULL)
432 			got_worktree_close(*worktree);
433 		*worktree = NULL;
434 	} else
435 		(*worktree)->lockfd = fd;
436 
437 	return err;
438 }
439 
440 const struct got_error *
441 got_worktree_open(struct got_worktree **worktree, const char *path)
442 {
443 	const struct got_error *err = NULL;
444 
445 	do {
446 		err = open_worktree(worktree, path);
447 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT))
448 			return err;
449 		if (*worktree)
450 			return NULL;
451 		path = dirname(path);
452 		if (path == NULL)
453 			return got_error_from_errno();
454 	} while (!((path[0] == '.' || path[0] == '/') && path[1] == '\0'));
455 
456 	return got_error(GOT_ERR_NOT_WORKTREE);
457 }
458 
459 const struct got_error *
460 got_worktree_close(struct got_worktree *worktree)
461 {
462 	const struct got_error *err = NULL;
463 	free(worktree->root_path);
464 	free(worktree->repo_path);
465 	free(worktree->path_prefix);
466 	free(worktree->base_commit_id);
467 	free(worktree->head_ref_name);
468 	if (worktree->lockfd != -1)
469 		if (close(worktree->lockfd) != 0)
470 			err = got_error_from_errno();
471 	free(worktree);
472 	return err;
473 }
474 
475 const char *
476 got_worktree_get_root_path(struct got_worktree *worktree)
477 {
478 	return worktree->root_path;
479 }
480 
481 const char *
482 got_worktree_get_repo_path(struct got_worktree *worktree)
483 {
484 	return worktree->repo_path;
485 }
486 
487 const char *
488 got_worktree_get_path_prefix(struct got_worktree *worktree)
489 {
490 	return worktree->path_prefix;
491 }
492 
493 const struct got_error *
494 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
495     const char *path_prefix)
496 {
497 	char *absprefix = NULL;
498 
499 	if (!got_path_is_absolute(path_prefix)) {
500 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
501 			return got_error_from_errno();
502 	}
503 	*match = (strcmp(absprefix ? absprefix : path_prefix,
504 	    worktree->path_prefix) == 0);
505 	free(absprefix);
506 	return NULL;
507 }
508 
509 const char *
510 got_worktree_get_head_ref_name(struct got_worktree *worktree)
511 {
512 	return worktree->head_ref_name;
513 }
514 
515 struct got_object_id *
516 got_worktree_get_base_commit_id(struct got_worktree *worktree)
517 {
518 	return worktree->base_commit_id;
519 }
520 
521 const struct got_error *
522 got_worktree_set_base_commit_id(struct got_worktree *worktree,
523     struct got_repository *repo, struct got_object_id *commit_id)
524 {
525 	const struct got_error *err;
526 	struct got_object *obj = NULL;
527 	char *id_str = NULL;
528 	char *path_got = NULL;
529 
530 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
531 	    GOT_WORKTREE_GOT_DIR) == -1) {
532 		err = got_error_from_errno();
533 		path_got = NULL;
534 		goto done;
535 	}
536 
537 	err = got_object_open(&obj, repo, commit_id);
538 	if (err)
539 		return err;
540 
541 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
542 		err = got_error(GOT_ERR_OBJ_TYPE);
543 		goto done;
544 	}
545 
546 	/* Record our base commit. */
547 	err = got_object_id_str(&id_str, commit_id);
548 	if (err)
549 		goto done;
550 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
551 	if (err)
552 		goto done;
553 
554 	free(worktree->base_commit_id);
555 	worktree->base_commit_id = got_object_id_dup(commit_id);
556 	if (worktree->base_commit_id == NULL) {
557 		err = got_error_from_errno();
558 		goto done;
559 	}
560 done:
561 	if (obj)
562 		got_object_close(obj);
563 	free(id_str);
564 	free(path_got);
565 	return err;
566 }
567 
568 static const struct got_error *
569 lock_worktree(struct got_worktree *worktree, int operation)
570 {
571 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
572 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
573 		    : got_error_from_errno());
574 	return NULL;
575 }
576 
577 static const struct got_error *
578 add_dir_on_disk(struct got_worktree *worktree, const char *path)
579 {
580 	const struct got_error *err = NULL;
581 	char *abspath;
582 
583 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
584 		return got_error_from_errno();
585 
586 	err = got_path_mkdir(abspath);
587 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
588 		struct stat sb;
589 		err = NULL;
590 		if (lstat(abspath, &sb) == -1) {
591 			err = got_error_from_errno();
592 		} else if (!S_ISDIR(sb.st_mode)) {
593 			/* TODO directory is obstructed; do something */
594 			err = got_error(GOT_ERR_FILE_OBSTRUCTED);
595 		}
596 	}
597 	free(abspath);
598 	return err;
599 }
600 
601 static const struct got_error *
602 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
603 {
604 	const struct got_error *err = NULL;
605 	uint8_t fbuf1[8192];
606 	uint8_t fbuf2[8192];
607 	size_t flen1 = 0, flen2 = 0;
608 
609 	*same = 1;
610 
611 	while (1) {
612 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
613 		if (flen1 == 0 && ferror(f1)) {
614 			err = got_error_from_errno();
615 			break;
616 		}
617 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
618 		if (flen2 == 0 && ferror(f2)) {
619 			err = got_error_from_errno();
620 			break;
621 		}
622 		if (flen1 == 0) {
623 			if (flen2 != 0)
624 				*same = 0;
625 			break;
626 		} else if (flen2 == 0) {
627 			if (flen1 != 0)
628 				*same = 0;
629 			break;
630 		} else if (flen1 == flen2) {
631 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
632 				*same = 0;
633 				break;
634 			}
635 		} else {
636 			*same = 0;
637 			break;
638 		}
639 	}
640 
641 	return err;
642 }
643 
644 static const struct got_error *
645 check_files_equal(int *same, const char *f1_path, const char *f2_path)
646 {
647 	const struct got_error *err = NULL;
648 	struct stat sb;
649 	size_t size1, size2;
650 	FILE *f1 = NULL, *f2 = NULL;
651 
652 	*same = 1;
653 
654 	if (lstat(f1_path, &sb) != 0) {
655 		err = got_error_from_errno();
656 		goto done;
657 	}
658 	size1 = sb.st_size;
659 
660 	if (lstat(f2_path, &sb) != 0) {
661 		err = got_error_from_errno();
662 		goto done;
663 	}
664 	size2 = sb.st_size;
665 
666 	if (size1 != size2) {
667 		*same = 0;
668 		return NULL;
669 	}
670 
671 	f1 = fopen(f1_path, "r");
672 	if (f1 == NULL)
673 		return got_error_from_errno();
674 
675 	f2 = fopen(f2_path, "r");
676 	if (f2 == NULL) {
677 		err = got_error_from_errno();
678 		goto done;
679 	}
680 
681 	err = check_file_contents_equal(same, f1, f2);
682 done:
683 	if (f1 && fclose(f1) != 0 && err == NULL)
684 		err = got_error_from_errno();
685 	if (f2 && fclose(f2) != 0 && err == NULL)
686 		err = got_error_from_errno();
687 
688 	return err;
689 }
690 
691 /*
692  * Perform a 3-way merge where the file's version in the file index (blob2)
693  * acts as the common ancestor, the incoming blob (blob1) acts as the first
694  * derived version, and the file on disk acts as the second derived version.
695  */
696 static const struct got_error *
697 merge_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
698    struct got_fileindex_entry *ie, const char *ondisk_path, const char *path,
699    uint16_t te_mode, uint16_t st_mode, struct got_blob_object *blob1,
700    struct got_repository *repo,
701    got_worktree_checkout_cb progress_cb, void *progress_arg)
702 {
703 	const struct got_error *err = NULL;
704 	int merged_fd = -1;
705 	struct got_blob_object *blob2 = NULL;
706 	FILE *f1 = NULL, *f2 = NULL;
707 	char *blob1_path = NULL, *blob2_path = NULL;
708 	char *merged_path = NULL, *base_path = NULL;
709 	char *id_str = NULL;
710 	char *label1 = NULL;
711 	int overlapcnt = 0, update_timestamps = 0;
712 	char *parent;
713 
714 	parent = dirname(ondisk_path);
715 	if (parent == NULL)
716 		return got_error_from_errno();
717 
718 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
719 		return got_error_from_errno();
720 
721 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
722 	if (err)
723 		goto done;
724 
725 	free(base_path);
726 	if (asprintf(&base_path, "%s/got-merge-blob1", parent) == -1) {
727 		err = got_error_from_errno();
728 		base_path = NULL;
729 		goto done;
730 	}
731 
732 	err = got_opentemp_named(&blob1_path, &f1, base_path);
733 	if (err)
734 		goto done;
735 	err = got_object_blob_dump_to_file(NULL, NULL, f1, blob1);
736 	if (err)
737 		goto done;
738 
739 	free(base_path);
740 	if (asprintf(&base_path, "%s/got-merge-blob2", parent) == -1) {
741 		err = got_error_from_errno();
742 		base_path = NULL;
743 		goto done;
744 	}
745 
746 	err = got_opentemp_named(&blob2_path, &f2, base_path);
747 	if (err)
748 		goto done;
749 	if (got_fileindex_entry_has_blob(ie)) {
750 		struct got_object_id id2;
751 		memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
752 		err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
753 		if (err)
754 			goto done;
755 		err = got_object_blob_dump_to_file(NULL, NULL, f2, blob2);
756 		if (err)
757 			goto done;
758 	} else {
759 		/*
760 		 * If the file has no blob, this is an "add vs add" conflict,
761 		 * and we simply use an empty ancestor file to make both files
762 		 * appear in the merged result in their entirety.
763 		 */
764 	}
765 
766 	err = got_object_id_str(&id_str, worktree->base_commit_id);
767 	if (err)
768 		goto done;
769 	if (asprintf(&label1, "commit %s", id_str) == -1) {
770 		err = got_error_from_errno();
771 		goto done;
772 	}
773 
774 	err = got_merge_diff3(&overlapcnt, merged_fd, blob1_path,
775 	    blob2_path, ondisk_path, label1, path);
776 	if (err)
777 		goto done;
778 
779 	(*progress_cb)(progress_arg,
780 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
781 
782 
783 	if (fsync(merged_fd) != 0) {
784 		err = got_error_from_errno();
785 		goto done;
786 	}
787 
788 	/* Check if a clean merge has subsumed all local changes. */
789 	if (overlapcnt == 0) {
790 		err = check_files_equal(&update_timestamps, blob1_path,
791 		    merged_path);
792 		if (err)
793 			goto done;
794 	}
795 
796 	if (chmod(merged_path, st_mode) != 0) {
797 		err = got_error_from_errno();
798 		goto done;
799 	}
800 
801 	if (rename(merged_path, ondisk_path) != 0) {
802 		err = got_error_from_errno();
803 		unlink(merged_path);
804 		goto done;
805 	}
806 
807 	/*
808 	 * Do not update timestamps of already modified files. Otherwise,
809 	 * a future status walk would treat them as unmodified files again.
810 	 */
811 	err = got_fileindex_entry_update(ie, ondisk_path,
812 	    blob1->id.sha1, worktree->base_commit_id->sha1, update_timestamps);
813 done:
814 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
815 		err = got_error_from_errno();
816 	if (f1 && fclose(f1) != 0 && err == NULL)
817 		err = got_error_from_errno();
818 	if (f2 && fclose(f2) != 0 && err == NULL)
819 		err = got_error_from_errno();
820 	if (blob2)
821 		got_object_blob_close(blob2);
822 	free(merged_path);
823 	free(base_path);
824 	if (blob1_path) {
825 		unlink(blob1_path);
826 		free(blob1_path);
827 	}
828 	if (blob2_path) {
829 		unlink(blob2_path);
830 		free(blob2_path);
831 	}
832 	free(id_str);
833 	free(label1);
834 	return err;
835 }
836 
837 static const struct got_error *
838 update_blob_fileindex_entry(struct got_worktree *worktree,
839     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
840     const char *ondisk_path, const char *path, struct got_blob_object *blob,
841     int update_timestamps)
842 {
843 	const struct got_error *err = NULL;
844 
845 	if (ie == NULL)
846 		ie = got_fileindex_entry_get(fileindex, path);
847 	if (ie)
848 		err = got_fileindex_entry_update(ie, ondisk_path,
849 		    blob->id.sha1, worktree->base_commit_id->sha1,
850 		    update_timestamps);
851 	else {
852 		struct got_fileindex_entry *new_ie;
853 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
854 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
855 		if (!err)
856 			err = got_fileindex_entry_add(fileindex, new_ie);
857 	}
858 	return err;
859 }
860 
861 static const struct got_error *
862 install_blob(struct got_worktree *worktree, const char *ondisk_path,
863    const char *path, uint16_t te_mode, uint16_t st_mode,
864    struct got_blob_object *blob, int restoring_missing_file,
865    int reverting_versioned_file, struct got_repository *repo,
866    got_worktree_checkout_cb progress_cb, void *progress_arg)
867 {
868 	const struct got_error *err = NULL;
869 	int fd = -1;
870 	size_t len, hdrlen;
871 	int update = 0;
872 	char *tmppath = NULL;
873 
874 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
875 	    GOT_DEFAULT_FILE_MODE);
876 	if (fd == -1) {
877 		if (errno == ENOENT) {
878 			char *parent = dirname(path);
879 			if (parent == NULL)
880 				return got_error_from_errno();
881 			err = add_dir_on_disk(worktree, parent);
882 			if (err)
883 				return err;
884 			fd = open(ondisk_path,
885 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
886 			    GOT_DEFAULT_FILE_MODE);
887 			if (fd == -1)
888 				return got_error_from_errno();
889 		} else if (errno == EEXIST) {
890 			if (!S_ISREG(st_mode)) {
891 				/* TODO file is obstructed; do something */
892 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
893 				goto done;
894 			} else {
895 				err = got_opentemp_named_fd(&tmppath, &fd,
896 				    ondisk_path);
897 				if (err)
898 					goto done;
899 				update = 1;
900 			}
901 		} else
902 			return got_error_from_errno();
903 	}
904 
905 	if (restoring_missing_file)
906 		(*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
907 	else if (reverting_versioned_file)
908 		(*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
909 	else
910 		(*progress_cb)(progress_arg,
911 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
912 
913 	hdrlen = got_object_blob_get_hdrlen(blob);
914 	do {
915 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
916 		err = got_object_blob_read_block(&len, blob);
917 		if (err)
918 			break;
919 		if (len > 0) {
920 			/* Skip blob object header first time around. */
921 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
922 			if (outlen == -1) {
923 				err = got_error_from_errno();
924 				goto done;
925 			} else if (outlen != len - hdrlen) {
926 				err = got_error(GOT_ERR_IO);
927 				goto done;
928 			}
929 			hdrlen = 0;
930 		}
931 	} while (len != 0);
932 
933 	if (fsync(fd) != 0) {
934 		err = got_error_from_errno();
935 		goto done;
936 	}
937 
938 	if (update) {
939 		if (rename(tmppath, ondisk_path) != 0) {
940 			err = got_error_from_errno();
941 			unlink(tmppath);
942 			goto done;
943 		}
944 	}
945 
946 	if (te_mode & S_IXUSR) {
947 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
948 			err = got_error_from_errno();
949 			goto done;
950 		}
951 	} else {
952 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
953 			err = got_error_from_errno();
954 			goto done;
955 		}
956 	}
957 
958 done:
959 	if (fd != -1 && close(fd) != 0 && err == NULL)
960 		err = got_error_from_errno();
961 	free(tmppath);
962 	return err;
963 }
964 
965 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
966 static const struct got_error *
967 get_modified_file_content_status(unsigned char *status, FILE *f)
968 {
969 	const struct got_error *err = NULL;
970 	const char *markers[3] = {
971 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
972 		GOT_DIFF_CONFLICT_MARKER_SEP,
973 		GOT_DIFF_CONFLICT_MARKER_END
974 	};
975 	int i = 0;
976 	char *line;
977 	size_t len;
978 	const char delim[3] = {'\0', '\0', '\0'};
979 
980 	while (*status == GOT_STATUS_MODIFY) {
981 		line = fparseln(f, &len, NULL, delim, 0);
982 		if (line == NULL) {
983 			if (feof(f))
984 				break;
985 			err = got_ferror(f, GOT_ERR_IO);
986 			break;
987 		}
988 
989 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
990 			if (markers[i] == GOT_DIFF_CONFLICT_MARKER_END)
991 				*status = GOT_STATUS_CONFLICT;
992 			else
993 				i++;
994 		}
995 	}
996 
997 	return err;
998 }
999 
1000 static const struct got_error *
1001 get_file_status(unsigned char *status, struct stat *sb,
1002     struct got_fileindex_entry *ie, const char *abspath,
1003     struct got_repository *repo)
1004 {
1005 	const struct got_error *err = NULL;
1006 	struct got_object_id id;
1007 	size_t hdrlen;
1008 	FILE *f = NULL;
1009 	uint8_t fbuf[8192];
1010 	struct got_blob_object *blob = NULL;
1011 	size_t flen, blen;
1012 
1013 	*status = GOT_STATUS_NO_CHANGE;
1014 
1015 	if (lstat(abspath, sb) == -1) {
1016 		if (errno == ENOENT) {
1017 			if (ie) {
1018 				if (got_fileindex_entry_has_file_on_disk(ie))
1019 					*status = GOT_STATUS_MISSING;
1020 				else
1021 					*status = GOT_STATUS_DELETE;
1022 				sb->st_mode =
1023 				    ((ie->mode >> GOT_FILEIDX_MODE_PERMS_SHIFT)
1024 				    & (S_IRWXU | S_IRWXG | S_IRWXO));
1025 			} else
1026 				sb->st_mode = GOT_DEFAULT_FILE_MODE;
1027 			return NULL;
1028 		}
1029 		return got_error_from_errno();
1030 	}
1031 
1032 	if (!S_ISREG(sb->st_mode)) {
1033 		*status = GOT_STATUS_OBSTRUCTED;
1034 		return NULL;
1035 	}
1036 
1037 	if (ie == NULL)
1038 		return NULL;
1039 
1040 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1041 		*status = GOT_STATUS_DELETE;
1042 		return NULL;
1043 	} else if (!got_fileindex_entry_has_blob(ie)) {
1044 		*status = GOT_STATUS_ADD;
1045 		return NULL;
1046 	}
1047 
1048 	if (ie->ctime_sec == sb->st_ctime &&
1049 	    ie->ctime_nsec == sb->st_ctimensec &&
1050 	    ie->mtime_sec == sb->st_mtime &&
1051 	    ie->mtime_sec == sb->st_mtime &&
1052 	    ie->mtime_nsec == sb->st_mtimensec &&
1053 	    ie->size == (sb->st_size & 0xffffffff))
1054 		return NULL;
1055 
1056 	memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1057 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1058 	if (err)
1059 		return err;
1060 
1061 	f = fopen(abspath, "r");
1062 	if (f == NULL) {
1063 		err = got_error_from_errno();
1064 		goto done;
1065 	}
1066 	hdrlen = got_object_blob_get_hdrlen(blob);
1067 	while (1) {
1068 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1069 		err = got_object_blob_read_block(&blen, blob);
1070 		if (err)
1071 			goto done;
1072 		/* Skip length of blob object header first time around. */
1073 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1074 		if (flen == 0 && ferror(f)) {
1075 			err = got_error_from_errno();
1076 			goto done;
1077 		}
1078 		if (blen == 0) {
1079 			if (flen != 0)
1080 				*status = GOT_STATUS_MODIFY;
1081 			break;
1082 		} else if (flen == 0) {
1083 			if (blen != 0)
1084 				*status = GOT_STATUS_MODIFY;
1085 			break;
1086 		} else if (blen - hdrlen == flen) {
1087 			/* Skip blob object header first time around. */
1088 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1089 				*status = GOT_STATUS_MODIFY;
1090 				break;
1091 			}
1092 		} else {
1093 			*status = GOT_STATUS_MODIFY;
1094 			break;
1095 		}
1096 		hdrlen = 0;
1097 	}
1098 
1099 	if (*status == GOT_STATUS_MODIFY) {
1100 		rewind(f);
1101 		err = get_modified_file_content_status(status, f);
1102 	}
1103 done:
1104 	if (blob)
1105 		got_object_blob_close(blob);
1106 	if (f)
1107 		fclose(f);
1108 	return err;
1109 }
1110 
1111 static const struct got_error *
1112 update_blob(struct got_worktree *worktree,
1113     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1114     struct got_tree_entry *te, const char *path,
1115     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1116     void *progress_arg)
1117 {
1118 	const struct got_error *err = NULL;
1119 	struct got_blob_object *blob = NULL;
1120 	char *ondisk_path;
1121 	unsigned char status = GOT_STATUS_NO_CHANGE;
1122 	struct stat sb;
1123 
1124 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1125 		return got_error_from_errno();
1126 
1127 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1128 	if (err)
1129 		goto done;
1130 
1131 	if (status == GOT_STATUS_OBSTRUCTED) {
1132 		(*progress_cb)(progress_arg, status, path);
1133 		goto done;
1134 	}
1135 
1136 	if (ie && status != GOT_STATUS_MISSING) {
1137 		if (got_fileindex_entry_has_commit(ie) &&
1138 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1139 		    SHA1_DIGEST_LENGTH) == 0) {
1140 			(*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1141 			    path);
1142 			goto done;
1143 		}
1144 		if (got_fileindex_entry_has_blob(ie) &&
1145 		    memcmp(ie->blob_sha1, te->id->sha1,
1146 		    SHA1_DIGEST_LENGTH) == 0)
1147 			goto done;
1148 	}
1149 
1150 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1151 	if (err)
1152 		goto done;
1153 
1154 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD)
1155 		err = merge_blob(worktree, fileindex, ie, ondisk_path, path,
1156 		    te->mode, sb.st_mode, blob, repo, progress_cb,
1157 		    progress_arg);
1158 	else if (status == GOT_STATUS_DELETE) {
1159 		(*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1160 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1161 		    ondisk_path, path, blob, 0);
1162 		if (err)
1163 			goto done;
1164 	} else {
1165 		err = install_blob(worktree, ondisk_path, path, te->mode,
1166 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1167 		    repo, progress_cb, progress_arg);
1168 		if (err)
1169 			goto done;
1170 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1171 		    ondisk_path, path, blob, 1);
1172 		if (err)
1173 			goto done;
1174 	}
1175 	got_object_blob_close(blob);
1176 done:
1177 	free(ondisk_path);
1178 	return err;
1179 }
1180 
1181 static const struct got_error *
1182 remove_ondisk_file(const char *root_path, const char *path)
1183 {
1184 	const struct got_error *err = NULL;
1185 	char *ondisk_path = NULL;
1186 
1187 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1188 		return got_error_from_errno();
1189 
1190 	if (unlink(ondisk_path) == -1) {
1191 		if (errno != ENOENT)
1192 			err = got_error_from_errno();
1193 	} else {
1194 		char *parent = dirname(ondisk_path);
1195 		while (parent && strcmp(parent, root_path) != 0) {
1196 			if (rmdir(parent) == -1) {
1197 				if (errno != ENOTEMPTY)
1198 					err = got_error_from_errno();
1199 				break;
1200 			}
1201 			parent = dirname(parent);
1202 		}
1203 	}
1204 	free(ondisk_path);
1205 	return err;
1206 }
1207 
1208 static const struct got_error *
1209 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1210     struct got_fileindex_entry *ie, const char *parent_path,
1211     struct got_repository *repo,
1212     got_worktree_checkout_cb progress_cb, void *progress_arg)
1213 {
1214 	const struct got_error *err = NULL;
1215 	unsigned char status;
1216 	struct stat sb;
1217 	char *ondisk_path;
1218 
1219 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1220 	    == -1)
1221 		return got_error_from_errno();
1222 
1223 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1224 	if (err)
1225 		return err;
1226 
1227 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1228 	    status == GOT_STATUS_ADD) {
1229 		(*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1230 		/*
1231 		 * Preserve the working file and change the deleted blob's
1232 		 * entry into a schedule-add entry.
1233 		 */
1234 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1235 		    0);
1236 		if (err)
1237 			return err;
1238 	} else {
1239 		(*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1240 		if (status == GOT_STATUS_NO_CHANGE) {
1241 			err = remove_ondisk_file(worktree->root_path, ie->path);
1242 			if (err)
1243 				return err;
1244 		}
1245 		got_fileindex_entry_remove(fileindex, ie);
1246 	}
1247 
1248 	return err;
1249 }
1250 
1251 struct diff_cb_arg {
1252     struct got_fileindex *fileindex;
1253     struct got_worktree *worktree;
1254     struct got_repository *repo;
1255     got_worktree_checkout_cb progress_cb;
1256     void *progress_arg;
1257     got_worktree_cancel_cb cancel_cb;
1258     void *cancel_arg;
1259 };
1260 
1261 static const struct got_error *
1262 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1263     struct got_tree_entry *te, const char *parent_path)
1264 {
1265 	struct diff_cb_arg *a = arg;
1266 
1267 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1268 		return got_error(GOT_ERR_CANCELLED);
1269 
1270 	return update_blob(a->worktree, a->fileindex, ie, te,
1271 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1272 }
1273 
1274 static const struct got_error *
1275 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1276 {
1277 	struct diff_cb_arg *a = arg;
1278 
1279 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1280 		return got_error(GOT_ERR_CANCELLED);
1281 
1282 	return delete_blob(a->worktree, a->fileindex, ie, parent_path,
1283 	    a->repo, a->progress_cb, a->progress_arg);
1284 }
1285 
1286 static const struct got_error *
1287 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1288 {
1289 	struct diff_cb_arg *a = arg;
1290 	const struct got_error *err;
1291 	char *path;
1292 
1293 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1294 		return got_error(GOT_ERR_CANCELLED);
1295 
1296 	if (asprintf(&path, "%s%s%s", parent_path,
1297 	    parent_path[0] ? "/" : "", te->name)
1298 	    == -1)
1299 		return got_error_from_errno();
1300 
1301 	if (S_ISDIR(te->mode))
1302 		err = add_dir_on_disk(a->worktree, path);
1303 	else
1304 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1305 		    a->repo, a->progress_cb, a->progress_arg);
1306 
1307 	free(path);
1308 	return err;
1309 }
1310 
1311 const struct got_error *
1312 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1313 {
1314 	const struct got_error *err = NULL;
1315 	char *uuidstr = NULL;
1316 	uint32_t uuid_status;
1317 
1318 	*refname = NULL;
1319 
1320 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1321 	if (uuid_status != uuid_s_ok)
1322 		return got_error_uuid(uuid_status);
1323 
1324 	if (asprintf(refname, "%s-%s", GOT_WORKTREE_BASE_REF_PREFIX, uuidstr)
1325 	    == -1) {
1326 		err = got_error_from_errno();
1327 		*refname = NULL;
1328 	}
1329 	free(uuidstr);
1330 	return err;
1331 }
1332 
1333 /*
1334  * Prevent Git's garbage collector from deleting our base commit by
1335  * setting a reference to our base commit's ID.
1336  */
1337 static const struct got_error *
1338 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1339 {
1340 	const struct got_error *err = NULL;
1341 	struct got_reference *ref = NULL;
1342 	char *refname;
1343 
1344 	err = got_worktree_get_base_ref_name(&refname, worktree);
1345 	if (err)
1346 		return err;
1347 
1348 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1349 	if (err)
1350 		goto done;
1351 
1352 	err = got_ref_write(ref, repo);
1353 done:
1354 	free(refname);
1355 	if (ref)
1356 		got_ref_close(ref);
1357 	return err;
1358 }
1359 
1360 static const struct got_error *
1361 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1362    struct got_worktree *worktree)
1363 {
1364 	const struct got_error *err = NULL;
1365 	FILE *index = NULL;
1366 
1367 	*fileindex_path = NULL;
1368 	*fileindex = got_fileindex_alloc();
1369 	if (*fileindex == NULL)
1370 		return got_error_from_errno();
1371 
1372 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1373 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1374 		err = got_error_from_errno();
1375 		*fileindex_path = NULL;
1376 		goto done;
1377 	}
1378 
1379 	index = fopen(*fileindex_path, "rb");
1380 	if (index == NULL) {
1381 		if (errno != ENOENT)
1382 			err = got_error_from_errno();
1383 	} else {
1384 		err = got_fileindex_read(*fileindex, index);
1385 		if (fclose(index) != 0 && err == NULL)
1386 			err = got_error_from_errno();
1387 	}
1388 done:
1389 	if (err) {
1390 		free(*fileindex_path);
1391 		*fileindex_path = NULL;
1392 		free(*fileindex);
1393 		*fileindex = NULL;
1394 	}
1395 	return err;
1396 }
1397 
1398 const struct got_error *
1399 got_worktree_checkout_files(struct got_worktree *worktree, const char *path,
1400     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1401     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1402 {
1403 	const struct got_error *err = NULL, *unlockerr, *checkout_err = NULL;
1404 	struct got_commit_object *commit = NULL;
1405 	struct got_object_id *tree_id = NULL;
1406 	struct got_tree_object *tree = NULL;
1407 	char *fileindex_path = NULL, *new_fileindex_path = NULL;
1408 	struct got_fileindex *fileindex = NULL;
1409 	FILE *new_index = NULL;
1410 	struct got_fileindex_diff_tree_cb diff_cb;
1411 	struct diff_cb_arg arg;
1412 	char *relpath = NULL, *entry_name = NULL;
1413 
1414 	err = lock_worktree(worktree, LOCK_EX);
1415 	if (err)
1416 		return err;
1417 
1418 	/*
1419 	 * Read the file index.
1420 	 * Checking out files is supposed to be an idempotent operation.
1421 	 * If the on-disk file index is incomplete we will try to complete it.
1422 	 */
1423 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1424 	if (err)
1425 		goto done;
1426 
1427 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1428 	    fileindex_path);
1429 	if (err)
1430 		goto done;
1431 
1432 	err = ref_base_commit(worktree, repo);
1433 	if (err)
1434 		goto done;
1435 
1436 	err = got_object_open_as_commit(&commit, repo,
1437 	   worktree->base_commit_id);
1438 	if (err)
1439 		goto done;
1440 
1441 	if (path[0]) {
1442 		char *tree_path;
1443 		int obj_type;
1444 		relpath = strdup(path);
1445 		if (relpath == NULL) {
1446 			err = got_error_from_errno();
1447 			goto done;
1448 		}
1449 		if (asprintf(&tree_path, "%s%s%s", worktree->path_prefix,
1450 		    got_path_is_root_dir(worktree->path_prefix) ? "" : "/",
1451 		    path) == -1) {
1452 			err = got_error_from_errno();
1453 			goto done;
1454 		}
1455 		err = got_object_id_by_path(&tree_id, repo,
1456 		    worktree->base_commit_id, tree_path);
1457 		free(tree_path);
1458 		if (err)
1459 			goto done;
1460 		err = got_object_get_type(&obj_type, repo, tree_id);
1461 		if (err)
1462 			goto done;
1463 		if (obj_type == GOT_OBJ_TYPE_BLOB) {
1464 			/* Split provided path into parent dir + entry name. */
1465 			if (strchr(path, '/')  == NULL) {
1466 				relpath = strdup("");
1467 				if (relpath == NULL) {
1468 					err = got_error_from_errno();
1469 					goto done;
1470 				}
1471 				tree_path = strdup(worktree->path_prefix);
1472 				if (tree_path == NULL) {
1473 					err = got_error_from_errno();
1474 					goto done;
1475 				}
1476 			} else {
1477 				err = got_path_dirname(&relpath, path);
1478 				if (err)
1479 					goto done;
1480 				if (asprintf(&tree_path, "%s%s%s",
1481 				    worktree->path_prefix,
1482 				    got_path_is_root_dir(
1483 				    worktree->path_prefix) ? "" : "/",
1484 				    relpath) == -1) {
1485 					err = got_error_from_errno();
1486 					goto done;
1487 				}
1488 			}
1489 			err = got_object_id_by_path(&tree_id, repo,
1490 			    worktree->base_commit_id, tree_path);
1491 			free(tree_path);
1492 			if (err)
1493 				goto done;
1494 			entry_name = basename(path);
1495 			if (entry_name == NULL) {
1496 				err = got_error_from_errno();
1497 				goto done;
1498 			}
1499 		}
1500 	} else {
1501 		relpath = strdup("");
1502 		if (relpath == NULL) {
1503 			err = got_error_from_errno();
1504 			goto done;
1505 		}
1506 		err = got_object_id_by_path(&tree_id, repo,
1507 		    worktree->base_commit_id, worktree->path_prefix);
1508 		if (err)
1509 			goto done;
1510 	}
1511 
1512 	err = got_object_open_as_tree(&tree, repo, tree_id);
1513 	if (err)
1514 		goto done;
1515 
1516 	if (entry_name &&
1517 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1518 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1519 		goto done;
1520 	}
1521 
1522 	diff_cb.diff_old_new = diff_old_new;
1523 	diff_cb.diff_old = diff_old;
1524 	diff_cb.diff_new = diff_new;
1525 	arg.fileindex = fileindex;
1526 	arg.worktree = worktree;
1527 	arg.repo = repo;
1528 	arg.progress_cb = progress_cb;
1529 	arg.progress_arg = progress_arg;
1530 	arg.cancel_cb = cancel_cb;
1531 	arg.cancel_arg = cancel_arg;
1532 	checkout_err = got_fileindex_diff_tree(fileindex, tree, relpath,
1533 	    entry_name, repo, &diff_cb, &arg);
1534 
1535 	/* Try to sync the fileindex back to disk in any case. */
1536 	err = got_fileindex_write(fileindex, new_index);
1537 	if (err)
1538 		goto done;
1539 
1540 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1541 		err = got_error_from_errno();
1542 		unlink(new_fileindex_path);
1543 		goto done;
1544 	}
1545 
1546 	free(new_fileindex_path);
1547 	new_fileindex_path = NULL;
1548 
1549 done:
1550 	free(relpath);
1551 	if (tree)
1552 		got_object_tree_close(tree);
1553 	if (commit)
1554 		got_object_commit_close(commit);
1555 	if (new_fileindex_path)
1556 		unlink(new_fileindex_path);
1557 	if (new_index)
1558 		fclose(new_index);
1559 	free(new_fileindex_path);
1560 	free(fileindex_path);
1561 	got_fileindex_free(fileindex);
1562 	if (checkout_err)
1563 		err = checkout_err;
1564 	unlockerr = lock_worktree(worktree, LOCK_SH);
1565 	if (unlockerr && err == NULL)
1566 		err = unlockerr;
1567 	return err;
1568 }
1569 
1570 struct diff_dir_cb_arg {
1571     struct got_fileindex *fileindex;
1572     struct got_worktree *worktree;
1573     const char *status_path;
1574     size_t status_path_len;
1575     struct got_repository *repo;
1576     got_worktree_status_cb status_cb;
1577     void *status_arg;
1578     got_worktree_cancel_cb cancel_cb;
1579     void *cancel_arg;
1580 };
1581 
1582 static const struct got_error *
1583 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
1584     got_worktree_status_cb status_cb, void *status_arg,
1585     struct got_repository *repo)
1586 {
1587 	const struct got_error *err = NULL;
1588 	unsigned char status = GOT_STATUS_NO_CHANGE;
1589 	struct stat sb;
1590 	struct got_object_id id;
1591 
1592 	err = get_file_status(&status, &sb, ie, abspath, repo);
1593 	if (err == NULL && status != GOT_STATUS_NO_CHANGE) {
1594 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1595 		err = (*status_cb)(status_arg, status, ie->path, &id);
1596 	}
1597 	return err;
1598 }
1599 
1600 static const struct got_error *
1601 status_old_new(void *arg, struct got_fileindex_entry *ie,
1602     struct dirent *de, const char *parent_path)
1603 {
1604 	const struct got_error *err = NULL;
1605 	struct diff_dir_cb_arg *a = arg;
1606 	char *abspath;
1607 
1608 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1609 		return got_error(GOT_ERR_CANCELLED);
1610 
1611 	if (got_path_cmp(parent_path, a->status_path) != 0 &&
1612 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
1613 		return NULL;
1614 
1615 	if (parent_path[0]) {
1616 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
1617 		    parent_path, de->d_name) == -1)
1618 			return got_error_from_errno();
1619 	} else {
1620 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
1621 		    de->d_name) == -1)
1622 			return got_error_from_errno();
1623 	}
1624 
1625 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
1626 	    a->repo);
1627 	free(abspath);
1628 	return err;
1629 }
1630 
1631 static const struct got_error *
1632 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1633 {
1634 	struct diff_dir_cb_arg *a = arg;
1635 	struct got_object_id id;
1636 	unsigned char status;
1637 
1638 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1639 		return got_error(GOT_ERR_CANCELLED);
1640 
1641 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
1642 		return NULL;
1643 
1644 	memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1645 	if (got_fileindex_entry_has_file_on_disk(ie))
1646 		status = GOT_STATUS_MISSING;
1647 	else
1648 		status = GOT_STATUS_DELETE;
1649 	return (*a->status_cb)(a->status_arg, status, ie->path, &id);
1650 }
1651 
1652 static const struct got_error *
1653 status_new(void *arg, struct dirent *de, const char *parent_path)
1654 {
1655 	const struct got_error *err = NULL;
1656 	struct diff_dir_cb_arg *a = arg;
1657 	char *path = NULL;
1658 
1659 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1660 		return got_error(GOT_ERR_CANCELLED);
1661 
1662 	if (de->d_type == DT_DIR)
1663 		return NULL;
1664 
1665 	/* XXX ignore symlinks for now */
1666 	if (de->d_type == DT_LNK)
1667 		return NULL;
1668 
1669 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
1670 		return NULL;
1671 
1672 	if (parent_path[0]) {
1673 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
1674 			return got_error_from_errno();
1675 	} else {
1676 		path = de->d_name;
1677 	}
1678 
1679 	err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED, path,
1680 	    NULL);
1681 	if (parent_path[0])
1682 		free(path);
1683 	return err;
1684 }
1685 
1686 const struct got_error *
1687 got_worktree_status(struct got_worktree *worktree, const char *path,
1688     struct got_repository *repo, got_worktree_status_cb status_cb,
1689     void *status_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1690 {
1691 	const struct got_error *err = NULL;
1692 	DIR *workdir = NULL;
1693 	char *fileindex_path = NULL;
1694 	struct got_fileindex *fileindex = NULL;
1695 	FILE *index = NULL;
1696 	struct got_fileindex_diff_dir_cb fdiff_cb;
1697 	struct diff_dir_cb_arg arg;
1698 	char *ondisk_path = NULL;
1699 
1700 	fileindex = got_fileindex_alloc();
1701 	if (fileindex == NULL) {
1702 		err = got_error_from_errno();
1703 		goto done;
1704 	}
1705 
1706 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
1707 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1708 		err = got_error_from_errno();
1709 		fileindex_path = NULL;
1710 		goto done;
1711 	}
1712 
1713 	index = fopen(fileindex_path, "rb");
1714 	if (index == NULL) {
1715 		if (errno != ENOENT) {
1716 			err = got_error_from_errno();
1717 			goto done;
1718 		}
1719 	} else {
1720 		err = got_fileindex_read(fileindex, index);
1721 		fclose(index);
1722 		if (err)
1723 			goto done;
1724 	}
1725 
1726 	if (asprintf(&ondisk_path, "%s%s%s",
1727 	    worktree->root_path, path[0] ? "/" : "", path) == -1) {
1728 		err = got_error_from_errno();
1729 		goto done;
1730 	}
1731 	workdir = opendir(ondisk_path);
1732 	if (workdir == NULL) {
1733 		if (errno == ENOTDIR || errno == ENOENT) {
1734 			struct got_fileindex_entry *ie;
1735 			ie = got_fileindex_entry_get(fileindex, path);
1736 			if (ie == NULL) {
1737 				err = got_error(GOT_ERR_BAD_PATH);
1738 				goto done;
1739 			}
1740 			err = report_file_status(ie, ondisk_path,
1741 			    status_cb, status_arg, repo);
1742 			goto done;
1743 		} else {
1744 			err = got_error_from_errno();
1745 			goto done;
1746 		}
1747 	}
1748 	fdiff_cb.diff_old_new = status_old_new;
1749 	fdiff_cb.diff_old = status_old;
1750 	fdiff_cb.diff_new = status_new;
1751 	arg.fileindex = fileindex;
1752 	arg.worktree = worktree;
1753 	arg.status_path = path;
1754 	arg.status_path_len = strlen(path);
1755 	arg.repo = repo;
1756 	arg.status_cb = status_cb;
1757 	arg.status_arg = status_arg;
1758 	arg.cancel_cb = cancel_cb;
1759 	arg.cancel_arg = cancel_arg;
1760 	err = got_fileindex_diff_dir(fileindex, workdir, worktree->root_path,
1761 	    path, repo, &fdiff_cb, &arg);
1762 done:
1763 	if (workdir)
1764 		closedir(workdir);
1765 	free(ondisk_path);
1766 	free(fileindex_path);
1767 	got_fileindex_free(fileindex);
1768 	return err;
1769 }
1770 
1771 const struct got_error *
1772 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
1773     const char *arg)
1774 {
1775 	const struct got_error *err = NULL;
1776 	char *resolved, *path = NULL;
1777 	size_t len;
1778 
1779 	*wt_path = NULL;
1780 
1781 	resolved = realpath(arg, NULL);
1782 	if (resolved == NULL)
1783 		return got_error_from_errno();
1784 
1785 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
1786 	    strlen(got_worktree_get_root_path(worktree)))) {
1787 		err = got_error(GOT_ERR_BAD_PATH);
1788 		goto done;
1789 	}
1790 
1791 	path = strdup(resolved +
1792 	    strlen(got_worktree_get_root_path(worktree)) + 1 /* skip '/' */);
1793 	if (path == NULL) {
1794 		err = got_error_from_errno();
1795 		goto done;
1796 	}
1797 
1798 	/* XXX status walk can't deal with trailing slash! */
1799 	len = strlen(path);
1800 	while (path[len - 1] == '/') {
1801 		path[len - 1] = '\0';
1802 		len--;
1803 	}
1804 done:
1805 	free(resolved);
1806 	if (err == NULL)
1807 		*wt_path = path;
1808 	else
1809 		free(path);
1810 	return err;
1811 }
1812 
1813 const struct got_error *
1814 got_worktree_schedule_add(struct got_worktree *worktree,
1815     const char *ondisk_path, got_worktree_status_cb status_cb, void *status_arg,
1816     struct got_repository *repo)
1817 {
1818 	struct got_fileindex *fileindex = NULL;
1819 	struct got_fileindex_entry *ie = NULL;
1820 	char *relpath, *fileindex_path = NULL, *new_fileindex_path = NULL;
1821 	FILE *index = NULL, *new_index = NULL;
1822 	const struct got_error *err = NULL, *unlockerr = NULL;
1823 	int ie_added = 0;
1824 
1825 	err = lock_worktree(worktree, LOCK_EX);
1826 	if (err)
1827 		return err;
1828 
1829 	err = got_path_skip_common_ancestor(&relpath,
1830 	    got_worktree_get_root_path(worktree), ondisk_path);
1831 	if (err)
1832 		goto done;
1833 
1834 	fileindex = got_fileindex_alloc();
1835 	if (fileindex == NULL) {
1836 		err = got_error_from_errno();
1837 		goto done;
1838 	}
1839 
1840 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
1841 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1842 		err = got_error_from_errno();
1843 		fileindex_path = NULL;
1844 		goto done;
1845 	}
1846 
1847 	index = fopen(fileindex_path, "rb");
1848 	if (index == NULL) {
1849 		err = got_error_from_errno();
1850 		goto done;
1851 	}
1852 
1853 	err = got_fileindex_read(fileindex, index);
1854 	if (err)
1855 		goto done;
1856 
1857 	if (got_fileindex_entry_get(fileindex, relpath) != NULL) {
1858 		err = got_error_set_errno(EEXIST);
1859 		goto done;
1860 	}
1861 
1862 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
1863 	if (err)
1864 		goto done;
1865 
1866 	err = got_fileindex_entry_add(fileindex, ie);
1867 	if (err)
1868 		goto done;
1869 	ie_added = 1; /* now owned by fileindex; don't free separately */
1870 
1871 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1872 	    fileindex_path);
1873 	if (err)
1874 		goto done;
1875 
1876 	err = got_fileindex_write(fileindex, new_index);
1877 	if (err)
1878 		goto done;
1879 
1880 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1881 		err = got_error_from_errno();
1882 		goto done;
1883 	}
1884 
1885 	free(new_fileindex_path);
1886 	new_fileindex_path = NULL;
1887 
1888 	err = report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
1889 done:
1890 	if (index) {
1891 		if (fclose(index) != 0 && err == NULL)
1892 			err = got_error_from_errno();
1893 	}
1894 	if (new_fileindex_path) {
1895 		if (unlink(new_fileindex_path) != 0 && err == NULL)
1896 			err = got_error_from_errno();
1897 		free(new_fileindex_path);
1898 	}
1899 	if (ie && !ie_added)
1900 		got_fileindex_entry_free(ie);
1901 	if (fileindex)
1902 		got_fileindex_free(fileindex);
1903 	unlockerr = lock_worktree(worktree, LOCK_SH);
1904 	if (unlockerr && err == NULL)
1905 		err = unlockerr;
1906 	free(relpath);
1907 	return err;
1908 }
1909 
1910 const struct got_error *
1911 got_worktree_schedule_delete(struct got_worktree *worktree,
1912     const char *ondisk_path, int delete_local_mods,
1913     got_worktree_status_cb status_cb, void *status_arg,
1914     struct got_repository *repo)
1915 {
1916 	struct got_fileindex *fileindex = NULL;
1917 	struct got_fileindex_entry *ie = NULL;
1918 	char *relpath, *fileindex_path = NULL, *new_fileindex_path = NULL;
1919 	FILE *index = NULL, *new_index = NULL;
1920 	const struct got_error *err = NULL, *unlockerr = NULL;
1921 	unsigned char status;
1922 	struct stat sb;
1923 
1924 	err = lock_worktree(worktree, LOCK_EX);
1925 	if (err)
1926 		return err;
1927 
1928 	err = got_path_skip_common_ancestor(&relpath,
1929 	    got_worktree_get_root_path(worktree), ondisk_path);
1930 	if (err)
1931 		goto done;
1932 
1933 	fileindex = got_fileindex_alloc();
1934 	if (fileindex == NULL) {
1935 		err = got_error_from_errno();
1936 		goto done;
1937 	}
1938 
1939 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
1940 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1941 		err = got_error_from_errno();
1942 		fileindex_path = NULL;
1943 		goto done;
1944 	}
1945 
1946 	index = fopen(fileindex_path, "rb");
1947 	if (index == NULL) {
1948 		err = got_error_from_errno();
1949 		goto done;
1950 	}
1951 
1952 	err = got_fileindex_read(fileindex, index);
1953 	if (err)
1954 		goto done;
1955 
1956 	ie = got_fileindex_entry_get(fileindex, relpath);
1957 	if (ie == NULL) {
1958 		err = got_error(GOT_ERR_BAD_PATH);
1959 		goto done;
1960 	}
1961 
1962 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1963 	if (err)
1964 		goto done;
1965 
1966 	if (status != GOT_STATUS_NO_CHANGE) {
1967 		if (status == GOT_STATUS_DELETE) {
1968 			err = got_error_set_errno(ENOENT);
1969 			goto done;
1970 		}
1971 		if (status != GOT_STATUS_MODIFY) {
1972 			err = got_error(GOT_ERR_FILE_STATUS);
1973 			goto done;
1974 		}
1975 		if (!delete_local_mods) {
1976 			err = got_error(GOT_ERR_FILE_MODIFIED);
1977 			goto done;
1978 		}
1979 	}
1980 
1981 	if (unlink(ondisk_path) != 0) {
1982 		err = got_error_from_errno();
1983 		goto done;
1984 	}
1985 
1986 	got_fileindex_entry_mark_deleted_from_disk(ie);
1987 
1988 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1989 	    fileindex_path);
1990 	if (err)
1991 		goto done;
1992 
1993 	err = got_fileindex_write(fileindex, new_index);
1994 	if (err)
1995 		goto done;
1996 
1997 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1998 		err = got_error_from_errno();
1999 		goto done;
2000 	}
2001 
2002 	free(new_fileindex_path);
2003 	new_fileindex_path = NULL;
2004 
2005 	err = report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2006 done:
2007 	free(relpath);
2008 	if (index) {
2009 		if (fclose(index) != 0 && err == NULL)
2010 			err = got_error_from_errno();
2011 	}
2012 	if (new_fileindex_path) {
2013 		if (unlink(new_fileindex_path) != 0 && err == NULL)
2014 			err = got_error_from_errno();
2015 		free(new_fileindex_path);
2016 	}
2017 	if (fileindex)
2018 		got_fileindex_free(fileindex);
2019 	unlockerr = lock_worktree(worktree, LOCK_SH);
2020 	if (unlockerr && err == NULL)
2021 		err = unlockerr;
2022 	return err;
2023 }
2024 
2025 const struct got_error *
2026 got_worktree_revert(struct got_worktree *worktree,
2027     const char *ondisk_path,
2028     got_worktree_checkout_cb progress_cb, void *progress_arg,
2029     struct got_repository *repo)
2030 {
2031 	struct got_fileindex *fileindex = NULL;
2032 	struct got_fileindex_entry *ie = NULL;
2033 	char *relpath, *fileindex_path = NULL, *new_fileindex_path = NULL;
2034 	char *tree_path = NULL, *parent_path, *te_name;
2035 	FILE *index = NULL, *new_index = NULL;
2036 	const struct got_error *err = NULL, *unlockerr = NULL;
2037 	struct got_tree_object *tree = NULL;
2038 	struct got_object_id id, *tree_id = NULL;
2039 	const struct got_tree_entry *te;
2040 	struct got_blob_object *blob = NULL;
2041 	unsigned char status;
2042 	struct stat sb;
2043 
2044 	err = lock_worktree(worktree, LOCK_EX);
2045 	if (err)
2046 		return err;
2047 
2048 	err = got_path_skip_common_ancestor(&relpath,
2049 	    got_worktree_get_root_path(worktree), ondisk_path);
2050 	if (err)
2051 		goto done;
2052 
2053 	fileindex = got_fileindex_alloc();
2054 	if (fileindex == NULL) {
2055 		err = got_error_from_errno();
2056 		goto done;
2057 	}
2058 
2059 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2060 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2061 		err = got_error_from_errno();
2062 		fileindex_path = NULL;
2063 		goto done;
2064 	}
2065 
2066 	index = fopen(fileindex_path, "rb");
2067 	if (index == NULL) {
2068 		err = got_error_from_errno();
2069 		goto done;
2070 	}
2071 
2072 	err = got_fileindex_read(fileindex, index);
2073 	if (err)
2074 		goto done;
2075 
2076 	ie = got_fileindex_entry_get(fileindex, relpath);
2077 	if (ie == NULL) {
2078 		err = got_error(GOT_ERR_BAD_PATH);
2079 		goto done;
2080 	}
2081 
2082 	/* Construct in-repository path of tree which contains this blob. */
2083 	err = got_path_dirname(&parent_path, ie->path);
2084 	if (err) {
2085 		if (err->code != GOT_ERR_BAD_PATH)
2086 			goto done;
2087 		parent_path = "/";
2088 	}
2089 	if (got_path_is_root_dir(worktree->path_prefix)) {
2090 		tree_path = strdup(parent_path);
2091 		if (tree_path == NULL) {
2092 			err = got_error_from_errno();
2093 			goto done;
2094 		}
2095 	} else {
2096 		if (got_path_is_root_dir(parent_path)) {
2097 			tree_path = strdup(worktree->path_prefix);
2098 			if (tree_path == NULL) {
2099 				err = got_error_from_errno();
2100 				goto done;
2101 			}
2102 		} else {
2103 			if (asprintf(&tree_path, "%s/%s",
2104 			    worktree->path_prefix, parent_path) == -1) {
2105 				err = got_error_from_errno();
2106 				goto done;
2107 			}
2108 		}
2109 	}
2110 
2111 	err = got_object_id_by_path(&tree_id, repo, worktree->base_commit_id,
2112 	    tree_path);
2113 	if (err)
2114 		goto done;
2115 
2116 	err = got_object_open_as_tree(&tree, repo, tree_id);
2117 	if (err)
2118 		goto done;
2119 
2120 	te_name = basename(ie->path);
2121 	if (te_name == NULL) {
2122 		err = got_error_from_errno();
2123 		goto done;
2124 	}
2125 
2126 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2127 	if (err)
2128 		goto done;
2129 
2130 	te = got_object_tree_find_entry(tree, te_name);
2131 	if (te == NULL && status != GOT_STATUS_ADD) {
2132 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
2133 		goto done;
2134 	}
2135 
2136 	switch (status) {
2137 	case GOT_STATUS_ADD:
2138 		(*progress_cb)(progress_arg, GOT_STATUS_REVERT, ie->path);
2139 		got_fileindex_entry_remove(fileindex, ie);
2140 		break;
2141 	case GOT_STATUS_DELETE:
2142 	case GOT_STATUS_MODIFY:
2143 	case GOT_STATUS_CONFLICT:
2144 	case GOT_STATUS_MISSING:
2145 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2146 		err = got_object_open_as_blob(&blob, repo, &id, 8192);
2147 		if (err)
2148 			goto done;
2149 		err = install_blob(worktree, ondisk_path, ie->path,
2150 		    te->mode, sb.st_mode, blob, 0, 1, repo, progress_cb,
2151 		    progress_arg);
2152 		if (err)
2153 			goto done;
2154 		if (status == GOT_STATUS_DELETE) {
2155 			err = update_blob_fileindex_entry(worktree,
2156 			    fileindex, ie, ondisk_path, ie->path, blob, 1);
2157 			if (err)
2158 				goto done;
2159 		}
2160 		break;
2161 	default:
2162 			goto done;
2163 	}
2164 
2165 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2166 	    fileindex_path);
2167 	if (err)
2168 		goto done;
2169 
2170 	err = got_fileindex_write(fileindex, new_index);
2171 	if (err)
2172 		goto done;
2173 
2174 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2175 		err = got_error_from_errno();
2176 		goto done;
2177 	}
2178 
2179 	free(new_fileindex_path);
2180 	new_fileindex_path = NULL;
2181 done:
2182 	free(relpath);
2183 	free(tree_path);
2184 	if (blob)
2185 		got_object_blob_close(blob);
2186 	if (tree)
2187 		got_object_tree_close(tree);
2188 	free(tree_id);
2189 	if (index) {
2190 		if (fclose(index) != 0 && err == NULL)
2191 			err = got_error_from_errno();
2192 	}
2193 	if (new_fileindex_path) {
2194 		if (unlink(new_fileindex_path) != 0 && err == NULL)
2195 			err = got_error_from_errno();
2196 		free(new_fileindex_path);
2197 	}
2198 	if (fileindex)
2199 		got_fileindex_free(fileindex);
2200 	unlockerr = lock_worktree(worktree, LOCK_SH);
2201 	if (unlockerr && err == NULL)
2202 		err = unlockerr;
2203 	return err;
2204 }
2205 
2206 struct commitable {
2207 	char *path;
2208 	char *in_repo_path;
2209 	char *ondisk_path;
2210 	unsigned char status;
2211 	struct got_object_id *blob_id;
2212 	struct got_object_id *base_id;
2213 	mode_t mode;
2214 };
2215 
2216 static void
2217 free_commitable(struct commitable *ct)
2218 {
2219 	free(ct->path);
2220 	free(ct->in_repo_path);
2221 	free(ct->ondisk_path);
2222 	free(ct->blob_id);
2223 	free(ct->base_id);
2224 	free(ct);
2225 }
2226 
2227 struct collect_commitables_arg {
2228 	struct got_pathlist_head *commitable_paths;
2229 	struct got_repository *repo;
2230 	struct got_worktree *worktree;
2231 };
2232 
2233 static const struct got_error *
2234 collect_commitables(void *arg, unsigned char status, const char *relpath,
2235     struct got_object_id *id)
2236 {
2237 	struct collect_commitables_arg *a = arg;
2238 	const struct got_error *err = NULL;
2239 	struct commitable *ct = NULL;
2240 	struct got_pathlist_entry *new = NULL;
2241 	char *parent_path = NULL, *path = NULL;
2242 	struct stat sb;
2243 
2244 	if (status == GOT_STATUS_CONFLICT)
2245 		return got_error(GOT_ERR_COMMIT_CONFLICT);
2246 
2247 	if (status != GOT_STATUS_MODIFY && status != GOT_STATUS_ADD &&
2248 	    status != GOT_STATUS_DELETE)
2249 		return NULL;
2250 
2251 	if (asprintf(&path, "/%s", relpath) == -1) {
2252 		err = got_error_from_errno();
2253 		goto done;
2254 	}
2255 	if (strcmp(path, "/") == 0) {
2256 		parent_path = strdup("");
2257 		if (parent_path == NULL)
2258 			return got_error_from_errno();
2259 	} else {
2260 		err = got_path_dirname(&parent_path, path);
2261 		if (err)
2262 			return err;
2263 	}
2264 
2265 	ct = calloc(1, sizeof(*ct));
2266 	if (ct == NULL) {
2267 		err = got_error_from_errno();
2268 		goto done;
2269 	}
2270 
2271 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
2272 	    relpath) == -1) {
2273 		err = got_error_from_errno();
2274 		goto done;
2275 	}
2276 	if (status == GOT_STATUS_DELETE) {
2277 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
2278 	} else {
2279 		if (lstat(ct->ondisk_path, &sb) != 0) {
2280 			err = got_error_from_errno();
2281 			goto done;
2282 		}
2283 		ct->mode = sb.st_mode;
2284 	}
2285 
2286 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
2287 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
2288 	    relpath) == -1) {
2289 		err = got_error_from_errno();
2290 		goto done;
2291 	}
2292 
2293 	ct->status = status;
2294 	ct->blob_id = NULL; /* will be filled in when blob gets created */
2295 	if (ct->status != GOT_STATUS_ADD) {
2296 		ct->base_id = got_object_id_dup(id);
2297 		if (ct->base_id == NULL) {
2298 			err = got_error_from_errno();
2299 			goto done;
2300 		}
2301 	}
2302 	ct->path = strdup(path);
2303 	if (ct->path == NULL) {
2304 		err = got_error_from_errno();
2305 		goto done;
2306 	}
2307 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
2308 done:
2309 	if (ct && (err || new == NULL))
2310 		free_commitable(ct);
2311 	free(parent_path);
2312 	free(path);
2313 	return err;
2314 }
2315 
2316 static const struct got_error *write_tree(struct got_object_id **,
2317     struct got_tree_object *, const char *, struct got_pathlist_head *,
2318     got_worktree_status_cb status_cb, void *status_arg,
2319     struct got_repository *);
2320 
2321 static const struct got_error *
2322 write_subtree(struct got_object_id **new_subtree_id,
2323     struct got_tree_entry *te, const char *parent_path,
2324     struct got_pathlist_head *commitable_paths,
2325     got_worktree_status_cb status_cb, void *status_arg,
2326     struct got_repository *repo)
2327 {
2328 	const struct got_error *err = NULL;
2329 	struct got_tree_object *subtree;
2330 	char *subpath;
2331 
2332 	if (asprintf(&subpath, "%s%s%s", parent_path,
2333 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
2334 		return got_error_from_errno();
2335 
2336 	err = got_object_open_as_tree(&subtree, repo, te->id);
2337 	if (err)
2338 		return err;
2339 
2340 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
2341 	    status_cb, status_arg, repo);
2342 	got_object_tree_close(subtree);
2343 	free(subpath);
2344 	return err;
2345 }
2346 
2347 static const struct got_error *
2348 match_ct_parent_path(int *match, struct commitable *ct, const char *path)
2349 {
2350 	const struct got_error *err = NULL;
2351 	char *ct_parent_path = NULL;
2352 
2353 	*match = 0;
2354 
2355 	if (strchr(ct->path, '/') == NULL) {
2356 		ct_parent_path = strdup("/");
2357 		if (ct_parent_path == NULL)
2358 			return got_error_from_errno();
2359 	} else {
2360 		err = got_path_dirname(&ct_parent_path, ct->path);
2361 		if (err)
2362 			return err;
2363 	}
2364 
2365 	*match = (strcmp(path, ct_parent_path) == 0);
2366 	free(ct_parent_path);
2367 	return err;
2368 }
2369 
2370 static mode_t
2371 get_ct_file_mode(struct commitable *ct)
2372 {
2373 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
2374 }
2375 
2376 static const struct got_error *
2377 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
2378     struct got_tree_entry *te, struct commitable *ct)
2379 {
2380 	const struct got_error *err = NULL;
2381 
2382 	*new_te = NULL;
2383 
2384 	err = got_object_tree_entry_dup(new_te, te);
2385 	if (err)
2386 		goto done;
2387 
2388 	(*new_te)->mode = get_ct_file_mode(ct);
2389 
2390 	free((*new_te)->id);
2391 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2392 	if ((*new_te)->id == NULL) {
2393 		err = got_error_from_errno();
2394 		goto done;
2395 	}
2396 done:
2397 	if (err && *new_te) {
2398 		got_object_tree_entry_close(*new_te);
2399 		*new_te = NULL;
2400 	}
2401 	return err;
2402 }
2403 
2404 static const struct got_error *
2405 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
2406     struct commitable *ct)
2407 {
2408 	const struct got_error *err = NULL;
2409 	char *ct_name;
2410 
2411 	 *new_te = NULL;
2412 
2413 	*new_te = calloc(1, sizeof(*new_te));
2414 	if (*new_te == NULL)
2415 		return got_error_from_errno();
2416 
2417 	ct_name = basename(ct->path);
2418 	if (ct_name == NULL) {
2419 		err = got_error_from_errno();
2420 		goto done;
2421 	}
2422 	(*new_te)->name = strdup(ct_name);
2423 	if ((*new_te)->name == NULL) {
2424 		err = got_error_from_errno();
2425 		goto done;
2426 	}
2427 
2428 	(*new_te)->mode = get_ct_file_mode(ct);
2429 
2430 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2431 	if ((*new_te)->id == NULL) {
2432 		err = got_error_from_errno();
2433 		goto done;
2434 	}
2435 done:
2436 	if (err && *new_te) {
2437 		got_object_tree_entry_close(*new_te);
2438 		*new_te = NULL;
2439 	}
2440 	return err;
2441 }
2442 
2443 static const struct got_error *
2444 insert_tree_entry(struct got_tree_entry *new_te,
2445     struct got_pathlist_head *paths)
2446 {
2447 	const struct got_error *err = NULL;
2448 	struct got_pathlist_entry *new_pe;
2449 
2450 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
2451 	if (err)
2452 		return err;
2453 	if (new_pe == NULL)
2454 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
2455 	return NULL;
2456 }
2457 
2458 static const struct got_error *
2459 report_ct_status(struct commitable *ct,
2460     got_worktree_status_cb status_cb, void *status_arg)
2461 {
2462 	const char *ct_path = ct->path;
2463 	while (ct_path[0] == '/')
2464 		ct_path++;
2465 	return (*status_cb)(status_arg, ct->status, ct_path, ct->blob_id);
2466 }
2467 
2468 static const struct got_error *
2469 match_modified_subtree(int *modified, struct got_tree_entry *te,
2470     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
2471 {
2472 	const struct got_error *err = NULL;
2473 	struct got_pathlist_entry *pe;
2474 	char *te_path;
2475 
2476 	*modified = 0;
2477 
2478 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
2479 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
2480 	    te->name) == -1)
2481 		return got_error_from_errno();
2482 
2483 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2484 		struct commitable *ct = pe->data;
2485 		char *ct_path;
2486 
2487 		if (asprintf(&ct_path, "%s%s%s", base_tree_path,
2488 		    got_path_is_root_dir(base_tree_path) ? "" : "/",
2489 		    te->name) == -1) {
2490 			err = got_error_from_errno();
2491 			break;
2492 		}
2493 
2494 		*modified = got_path_is_child(ct->in_repo_path, te_path,
2495 		    strlen(te_path));
2496 		 if (*modified)
2497 			break;
2498 	}
2499 
2500 	free(te_path);
2501 	return err;
2502 }
2503 
2504 static const struct got_error *
2505 match_deleted_or_modified_ct(struct commitable **ctp,
2506     struct got_tree_entry *te, const char *base_tree_path,
2507     struct got_pathlist_head *commitable_paths)
2508 {
2509 	const struct got_error *err = NULL;
2510 	struct got_pathlist_entry *pe;
2511 
2512 	*ctp = NULL;
2513 
2514 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2515 		struct commitable *ct = pe->data;
2516 		char *ct_name = NULL;
2517 		int path_matches;
2518 
2519 		if (ct->status != GOT_STATUS_MODIFY &&
2520 		    ct->status != GOT_STATUS_DELETE)
2521 			continue;
2522 
2523 		if (got_object_id_cmp(ct->base_id, te->id) != 0)
2524 			continue;
2525 
2526 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
2527 		 if (err)
2528 			return err;
2529 		if (!path_matches)
2530 			continue;
2531 
2532 		ct_name = basename(pe->path);
2533 		if (ct_name == NULL)
2534 			return got_error_from_errno();
2535 
2536 		if (strcmp(te->name, ct_name) != 0)
2537 			continue;
2538 
2539 		*ctp = ct;
2540 		break;
2541 	}
2542 
2543 	return err;
2544 }
2545 
2546 static const struct got_error *
2547 write_tree(struct got_object_id **new_tree_id,
2548     struct got_tree_object *base_tree, const char *path_base_tree,
2549     struct got_pathlist_head *commitable_paths,
2550     got_worktree_status_cb status_cb, void *status_arg,
2551     struct got_repository *repo)
2552 {
2553 	const struct got_error *err = NULL;
2554 	const struct got_tree_entries *base_entries = NULL;
2555 	struct got_pathlist_head paths;
2556 	struct got_tree_entries new_tree_entries;
2557 	struct got_tree_entry *te, *new_te = NULL;
2558 	struct got_pathlist_entry *pe;
2559 
2560 	TAILQ_INIT(&paths);
2561 	new_tree_entries.nentries = 0;
2562 	SIMPLEQ_INIT(&new_tree_entries.head);
2563 
2564 	/* Insert, and recurse into, newly added entries first. */
2565 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2566 		struct commitable *ct = pe->data;
2567 		char *child_path = NULL, *slash;
2568 
2569 		if (ct->status != GOT_STATUS_ADD)
2570 			continue;
2571 
2572 		 if (!got_path_is_child(pe->path, path_base_tree,
2573 		     strlen(path_base_tree)))
2574 			continue;
2575 
2576 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
2577 		    pe->path);
2578 		if (err)
2579 			goto done;
2580 
2581 		slash = strchr(child_path, '/');
2582 		if (slash == NULL) {
2583 			err = alloc_added_blob_tree_entry(&new_te, ct);
2584 			if (err)
2585 				goto done;
2586 			err = report_ct_status(ct, status_cb, status_arg);
2587 			if (err)
2588 				goto done;
2589 		} else {
2590 			char *subtree_path;
2591 			struct got_pathlist_entry *pe2;
2592 			int visited = 0;
2593 
2594 			*slash = '\0'; /* trim trailing path components */
2595 			if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
2596 			    got_path_is_root_dir(path_base_tree) ? "" : "/",
2597 			    child_path) == -1) {
2598 				err = got_error_from_errno();
2599 				goto done;
2600 			}
2601 			TAILQ_FOREACH(pe2, &paths, entry) {
2602 				if (got_path_cmp(subtree_path, pe2->path) != 0)
2603 					continue;
2604 				visited = 1;
2605 				break;
2606 			}
2607 			if (visited)
2608 				continue;
2609 
2610 			new_te = calloc(1, sizeof(*new_te));
2611 			new_te->mode = S_IFDIR;
2612 			new_te->name = strdup(child_path);
2613 			if (new_te->name == NULL) {
2614 				err = got_error_from_errno();
2615 				got_object_tree_entry_close(new_te);
2616 				new_te = NULL;
2617 				goto done;
2618 			}
2619 			err = write_tree(&new_te->id, NULL, subtree_path,
2620 			    commitable_paths, status_cb, status_arg, repo);
2621 			free(subtree_path);
2622 			if (err) {
2623 				got_object_tree_entry_close(new_te);
2624 				new_te = NULL;
2625 				goto done;
2626 			}
2627 		}
2628 		err = insert_tree_entry(new_te, &paths);
2629 		if (err)
2630 			goto done;
2631 	}
2632 
2633 	if (base_tree) {
2634 		/* Handle modified and deleted entries. */
2635 		base_entries = got_object_tree_get_entries(base_tree);
2636 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
2637 			struct commitable *ct = NULL;
2638 
2639 			if (S_ISDIR(te->mode)) {
2640 				int modified;
2641 				err = got_object_tree_entry_dup(&new_te, te);
2642 				if (err)
2643 					goto done;
2644 				err = match_modified_subtree(&modified, te,
2645 				    path_base_tree, commitable_paths);
2646 				if (err)
2647 					goto done;
2648 				/* Avoid recursion into unmodified subtrees. */
2649 				if (modified) {
2650 					free(new_te->id);
2651 					err = write_subtree(&new_te->id, te,
2652 					    path_base_tree, commitable_paths,
2653 					    status_cb, status_arg, repo);
2654 					if (err)
2655 						goto done;
2656 				}
2657 				err = insert_tree_entry(new_te, &paths);
2658 				if (err)
2659 					goto done;
2660 				continue;
2661 			}
2662 
2663 			err = match_deleted_or_modified_ct(&ct, te,
2664 			    path_base_tree, commitable_paths);
2665 			if (ct) {
2666 				/* NB: Deleted entries get dropped here. */
2667 				if (ct->status == GOT_STATUS_MODIFY) {
2668 					err = alloc_modified_blob_tree_entry(
2669 					    &new_te, te, ct);
2670 					if (err)
2671 						goto done;
2672 					err = insert_tree_entry(new_te, &paths);
2673 					if (err)
2674 						goto done;
2675 				}
2676 				err = report_ct_status(ct, status_cb, status_arg);
2677 				if (err)
2678 					goto done;
2679 			} else {
2680 				/* Entry is unchanged; just copy it. */
2681 				err = got_object_tree_entry_dup(&new_te, te);
2682 				if (err)
2683 					goto done;
2684 				err = insert_tree_entry(new_te, &paths);
2685 				if (err)
2686 					goto done;
2687 			}
2688 		}
2689 	}
2690 
2691 	/* Write new list of entries; deleted entries have been dropped. */
2692 	TAILQ_FOREACH(pe, &paths, entry) {
2693 		struct got_tree_entry *te = pe->data;
2694 		new_tree_entries.nentries++;
2695 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
2696 	}
2697 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
2698 done:
2699 	got_object_tree_entries_close(&new_tree_entries);
2700 	got_pathlist_free(&paths);
2701 	return err;
2702 }
2703 
2704 static const struct got_error *
2705 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
2706     struct got_object_id *new_base_commit_id, struct got_worktree *worktree)
2707 {
2708 	const struct got_error *err = NULL;
2709 	char *fileindex_path = NULL, *new_fileindex_path = NULL;
2710 	struct got_fileindex *fileindex = NULL;
2711 	FILE *new_index = NULL;
2712 	struct got_pathlist_entry *pe;
2713 
2714 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2715 	if (err)
2716 		return err;
2717 
2718 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2719 	    fileindex_path);
2720 	if (err)
2721 		goto done;
2722 
2723 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2724 		struct got_fileindex_entry *ie;
2725 		struct commitable *ct = pe->data;
2726 
2727 		ie = got_fileindex_entry_get(fileindex, pe->path);
2728 		if (ie) {
2729 			if (ct->status == GOT_STATUS_DELETE) {
2730 				got_fileindex_entry_remove(fileindex, ie);
2731 				got_fileindex_entry_free(ie);
2732 			} else
2733 				err = got_fileindex_entry_update(ie,
2734 				    ct->ondisk_path, ct->blob_id->sha1,
2735 				    new_base_commit_id->sha1, 1);
2736 		} else {
2737 			err = got_fileindex_entry_alloc(&ie,
2738 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
2739 			    new_base_commit_id->sha1);
2740 			if (err)
2741 				goto done;
2742 			err = got_fileindex_entry_add(fileindex, ie);
2743 			if (err)
2744 				goto done;
2745 		}
2746 	}
2747 
2748 	err = got_fileindex_write(fileindex, new_index);
2749 	if (err)
2750 		goto done;
2751 
2752 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2753 		err = got_error_from_errno();
2754 		unlink(new_fileindex_path);
2755 		goto done;
2756 	}
2757 
2758 	free(new_fileindex_path);
2759 	new_fileindex_path = NULL;
2760 
2761 done:
2762 	if (new_fileindex_path)
2763 		unlink(new_fileindex_path);
2764 	if (new_index)
2765 		fclose(new_index);
2766 	free(new_fileindex_path);
2767 	free(fileindex_path);
2768 	got_fileindex_free(fileindex);
2769 	return err;
2770 }
2771 
2772 static const struct got_error *
2773 check_ct_out_of_date(struct commitable *ct, struct got_repository *repo,
2774 	struct got_object_id *head_commit_id)
2775 {
2776 	const struct got_error *err = NULL;
2777 	struct got_object_id *id_in_head;
2778 
2779 	/*
2780 	 * XXX This should probably be checking each commit from
2781 	 * worktree's base_commit -> head and verify that the
2782 	 * same blob exists in each of these commits.
2783 	 * Removals+additions within this line of history could mean
2784 	 * that renames have occured in which case we should really
2785 	 * be forcing the user to run an update...
2786 	 */
2787 	err = got_object_id_by_path(&id_in_head, repo,
2788 	    head_commit_id, ct->in_repo_path);
2789 	if (err) {
2790 		if (err->code != GOT_ERR_NO_TREE_ENTRY)
2791 			return err;
2792 		if (ct->status != GOT_STATUS_ADD)
2793 			return got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
2794 		err = NULL;
2795 		id_in_head = NULL;
2796 	}
2797 
2798 	if (id_in_head && got_object_id_cmp(id_in_head, ct->base_id) != 0)
2799 		err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
2800 
2801 	free(id_in_head);
2802 	return err;
2803 }
2804 
2805 const struct got_error *
2806 got_worktree_commit(struct got_object_id **new_commit_id,
2807     struct got_worktree *worktree, const char *ondisk_path,
2808     const char *author, const char *committer, const char *logmsg,
2809     got_worktree_status_cb status_cb, void *status_arg,
2810     struct got_repository *repo)
2811 {
2812 	const struct got_error *err = NULL, *unlockerr = NULL;
2813 	struct collect_commitables_arg cc_arg;
2814 	struct got_pathlist_head commitable_paths;
2815 	struct got_pathlist_entry *pe;
2816 	char *relpath = NULL;
2817 	const char *head_ref_name = NULL;
2818 	struct got_reference *head_ref = NULL;
2819 	struct got_commit_object *head_commit = NULL;
2820 	struct got_object_id *head_commit_id = NULL;
2821 	struct got_reference *head_ref2 = NULL;
2822 	struct got_object_id *head_commit_id2 = NULL;
2823 	struct got_tree_object *head_tree = NULL;
2824 	struct got_object_id *new_tree_id = NULL;
2825 	struct got_object_id_queue parent_ids;
2826 	struct got_object_qid *pid = NULL;
2827 
2828 	*new_commit_id = NULL;
2829 
2830 	TAILQ_INIT(&commitable_paths);
2831 	SIMPLEQ_INIT(&parent_ids);
2832 
2833 	if (ondisk_path) {
2834 		err = got_path_skip_common_ancestor(&relpath,
2835 		    worktree->root_path, ondisk_path);
2836 		if (err)
2837 			return err;
2838 	}
2839 
2840 	err = lock_worktree(worktree, LOCK_EX);
2841 	if (err)
2842 		goto done;
2843 
2844 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name);
2845 	if (err)
2846 		goto done;
2847 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
2848 	if (err)
2849 		goto done;
2850 
2851 	cc_arg.commitable_paths = &commitable_paths;
2852 	cc_arg.worktree = worktree;
2853 	cc_arg.repo = repo;
2854 	err = got_worktree_status(worktree, relpath ? relpath : "",
2855 	    repo, collect_commitables, &cc_arg, NULL, NULL);
2856 	if (err)
2857 		goto done;
2858 
2859 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
2860 	if (err)
2861 		goto done;
2862 
2863 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
2864 		struct commitable *ct = pe->data;
2865 		err = check_ct_out_of_date(ct, repo, head_commit_id);
2866 		if (err)
2867 			goto done;
2868 	}
2869 
2870 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
2871 	if (err)
2872 		goto done;
2873 
2874 	/* TODO: collect commit message if not specified */
2875 
2876 	/* Create blobs from added and modified files and record their IDs. */
2877 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
2878 		struct commitable *ct = pe->data;
2879 		char *ondisk_path;
2880 
2881 		if (ct->status != GOT_STATUS_ADD &&
2882 		    ct->status != GOT_STATUS_MODIFY)
2883 			continue;
2884 
2885 		if (asprintf(&ondisk_path, "%s/%s",
2886 		    worktree->root_path, pe->path) == -1) {
2887 			err = got_error_from_errno();
2888 			goto done;
2889 		}
2890 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
2891 		free(ondisk_path);
2892 		if (err)
2893 			goto done;
2894 	}
2895 
2896 	/* Recursively write new tree objects. */
2897 	err = write_tree(&new_tree_id, head_tree, "/", &commitable_paths,
2898 	    status_cb, status_arg, repo);
2899 	if (err)
2900 		goto done;
2901 
2902 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
2903 	if (err)
2904 		goto done;
2905 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
2906 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
2907 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
2908 	got_object_qid_free(pid);
2909 	if (err)
2910 		goto done;
2911 
2912 	/* Check if a concurrent commit to our branch has occurred. */
2913 	/* XXX ideally we'd lock the reference file here to avoid a race */
2914 	head_ref_name = got_worktree_get_head_ref_name(worktree);
2915 	if (head_ref_name == NULL) {
2916 		err = got_error_from_errno();
2917 		goto done;
2918 	}
2919 	err = got_ref_open(&head_ref2, repo, head_ref_name);
2920 	if (err)
2921 		goto done;
2922 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
2923 	if (err)
2924 		goto done;
2925 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
2926 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
2927 		goto done;
2928 	}
2929 	/* Update branch head in repository. */
2930 	err = got_ref_change_ref(head_ref, *new_commit_id);
2931 	if (err)
2932 		goto done;
2933 	err = got_ref_write(head_ref, repo);
2934 	if (err)
2935 		goto done;
2936 	/* XXX race has ended here */
2937 
2938 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
2939 	if (err)
2940 		goto done;
2941 
2942 	err = ref_base_commit(worktree, repo);
2943 	if (err)
2944 		goto done;
2945 
2946 	err = update_fileindex_after_commit(&commitable_paths,
2947 	    *new_commit_id, worktree);
2948 	if (err)
2949 		goto done;
2950 done:
2951 	unlockerr = lock_worktree(worktree, LOCK_SH);
2952 	if (unlockerr && err == NULL)
2953 		err = unlockerr;
2954 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
2955 		struct commitable *ct = pe->data;
2956 		free_commitable(ct);
2957 	}
2958 	got_pathlist_free(&commitable_paths);
2959 	if (head_tree)
2960 		got_object_tree_close(head_tree);
2961 	if (head_commit)
2962 		got_object_commit_close(head_commit);
2963 	free(relpath);
2964 	free(head_commit_id);
2965 	free(head_commit_id2);
2966 	if (head_ref)
2967 		got_ref_close(head_ref);
2968 	if (head_ref2)
2969 		got_ref_close(head_ref2);
2970 	return err;
2971 }