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 
45 #include "got_lib_worktree.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("asprintf");
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_errno2("open", path);
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("dprintf");
84 			goto done;
85 		}
86 	}
87 
88 done:
89 	if (fd != -1 && close(fd) == -1 && err == NULL)
90 		err = got_error_from_errno("close");
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("asprintf");
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_errno2("fprintf", tmppath);
117 			goto done;
118 		}
119 	}
120 
121 	if (rename(tmppath, path) != 0) {
122 		err = got_error_from_errno3("rename", tmppath, path);
123 		unlink(tmppath);
124 		goto done;
125 	}
126 
127 done:
128 	if (fclose(tmpfile) != 0 && err == NULL)
129 		err = got_error_from_errno2("fclose", tmppath);
130 	free(tmppath);
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("asprintf");
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_errno2("open", path);
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_errno2("flock", path));
162 		goto done;
163 	}
164 
165 	if (lstat(path, &sb) != 0) {
166 		err = got_error_from_errno2("lstat", path);
167 		goto done;
168 	}
169 	*content = calloc(1, sb.st_size);
170 	if (*content == NULL) {
171 		err = got_error_from_errno("calloc");
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_errno2("read", path) :
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_errno2("close", path_got);
190 	free(path);
191 	if (err) {
192 		free(*content);
193 		*content = NULL;
194 	}
195 	return err;
196 }
197 
198 static const struct got_error *
199 write_head_ref(const char *path_got, struct got_reference *head_ref)
200 {
201 	const struct got_error *err = NULL;
202 	char *refstr = NULL;
203 
204 	if (got_ref_is_symbolic(head_ref)) {
205 		refstr = got_ref_to_str(head_ref);
206 		if (refstr == NULL)
207 			return got_error_from_errno("got_ref_to_str");
208 	} else {
209 		refstr = strdup(got_ref_get_name(head_ref));
210 		if (refstr == NULL)
211 			return got_error_from_errno("strdup");
212 	}
213 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
214 	free(refstr);
215 	return err;
216 }
217 
218 const struct got_error *
219 got_worktree_init(const char *path, struct got_reference *head_ref,
220     const char *prefix, struct got_repository *repo)
221 {
222 	const struct got_error *err = NULL;
223 	struct got_object_id *commit_id = NULL;
224 	uuid_t uuid;
225 	uint32_t uuid_status;
226 	int obj_type;
227 	char *path_got = NULL;
228 	char *formatstr = NULL;
229 	char *absprefix = NULL;
230 	char *basestr = NULL;
231 	char *uuidstr = NULL;
232 
233 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
234 		err = got_error(GOT_ERR_WORKTREE_REPO);
235 		goto done;
236 	}
237 
238 	err = got_ref_resolve(&commit_id, repo, head_ref);
239 	if (err)
240 		return err;
241 	err = got_object_get_type(&obj_type, repo, commit_id);
242 	if (err)
243 		return err;
244 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
245 		return got_error(GOT_ERR_OBJ_TYPE);
246 
247 	if (!got_path_is_absolute(prefix)) {
248 		if (asprintf(&absprefix, "/%s", prefix) == -1)
249 			return got_error_from_errno("asprintf");
250 	}
251 
252 	/* Create top-level directory (may already exist). */
253 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
254 		err = got_error_from_errno2("mkdir", path);
255 		goto done;
256 	}
257 
258 	/* Create .got directory (may already exist). */
259 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
260 		err = got_error_from_errno("asprintf");
261 		goto done;
262 	}
263 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
264 		err = got_error_from_errno2("mkdir", path_got);
265 		goto done;
266 	}
267 
268 	/* Create an empty lock file. */
269 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
270 	if (err)
271 		goto done;
272 
273 	/* Create an empty file index. */
274 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
275 	if (err)
276 		goto done;
277 
278 	/* Write the HEAD reference. */
279 	err = write_head_ref(path_got, head_ref);
280 	if (err)
281 		goto done;
282 
283 	/* Record our base commit. */
284 	err = got_object_id_str(&basestr, commit_id);
285 	if (err)
286 		goto done;
287 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
288 	if (err)
289 		goto done;
290 
291 	/* Store path to repository. */
292 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
293 	    got_repo_get_path(repo));
294 	if (err)
295 		goto done;
296 
297 	/* Store in-repository path prefix. */
298 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
299 	    absprefix ? absprefix : prefix);
300 	if (err)
301 		goto done;
302 
303 	/* Generate UUID. */
304 	uuid_create(&uuid, &uuid_status);
305 	if (uuid_status != uuid_s_ok) {
306 		err = got_error_uuid(uuid_status);
307 		goto done;
308 	}
309 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
310 	if (uuid_status != uuid_s_ok) {
311 		err = got_error_uuid(uuid_status);
312 		goto done;
313 	}
314 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
315 	if (err)
316 		goto done;
317 
318 	/* Stamp work tree with format file. */
319 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
320 		err = got_error_from_errno("asprintf");
321 		goto done;
322 	}
323 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
324 	if (err)
325 		goto done;
326 
327 done:
328 	free(commit_id);
329 	free(path_got);
330 	free(formatstr);
331 	free(absprefix);
332 	free(basestr);
333 	free(uuidstr);
334 	return err;
335 }
336 
337 static const struct got_error *
338 open_worktree(struct got_worktree **worktree, const char *path)
339 {
340 	const struct got_error *err = NULL;
341 	char *path_got;
342 	char *formatstr = NULL;
343 	char *uuidstr = NULL;
344 	char *path_lock = NULL;
345 	char *base_commit_id_str = NULL;
346 	int version, fd = -1;
347 	const char *errstr;
348 	struct got_repository *repo = NULL;
349 	uint32_t uuid_status;
350 
351 	*worktree = NULL;
352 
353 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
354 		err = got_error_from_errno("asprintf");
355 		path_got = NULL;
356 		goto done;
357 	}
358 
359 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
360 		err = got_error_from_errno("asprintf");
361 		path_lock = NULL;
362 		goto done;
363 	}
364 
365 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
366 	if (fd == -1) {
367 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
368 		    : got_error_from_errno2("open", path_lock));
369 		goto done;
370 	}
371 
372 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
373 	if (err)
374 		goto done;
375 
376 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
377 	if (errstr) {
378 		err = got_error(GOT_ERR_WORKTREE_META);
379 		goto done;
380 	}
381 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
382 		err = got_error(GOT_ERR_WORKTREE_VERS);
383 		goto done;
384 	}
385 
386 	*worktree = calloc(1, sizeof(**worktree));
387 	if (*worktree == NULL) {
388 		err = got_error_from_errno("calloc");
389 		goto done;
390 	}
391 	(*worktree)->lockfd = -1;
392 
393 	(*worktree)->root_path = strdup(path);
394 	if ((*worktree)->root_path == NULL) {
395 		err = got_error_from_errno("strdup");
396 		goto done;
397 	}
398 	err = read_meta_file(&(*worktree)->repo_path, path_got,
399 	    GOT_WORKTREE_REPOSITORY);
400 	if (err)
401 		goto done;
402 
403 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
404 	    GOT_WORKTREE_PATH_PREFIX);
405 	if (err)
406 		goto done;
407 
408 	err = read_meta_file(&base_commit_id_str, path_got,
409 	    GOT_WORKTREE_BASE_COMMIT);
410 	if (err)
411 		goto done;
412 
413 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
414 	if (err)
415 		goto done;
416 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
417 	if (uuid_status != uuid_s_ok) {
418 		err = got_error_uuid(uuid_status);
419 		goto done;
420 	}
421 
422 	err = got_repo_open(&repo, (*worktree)->repo_path);
423 	if (err)
424 		goto done;
425 
426 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
427 	    base_commit_id_str);
428 	if (err)
429 		goto done;
430 
431 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
432 	    GOT_WORKTREE_HEAD_REF);
433 done:
434 	if (repo)
435 		got_repo_close(repo);
436 	free(path_got);
437 	free(path_lock);
438 	free(base_commit_id_str);
439 	free(uuidstr);
440 	free(formatstr);
441 	if (err) {
442 		if (fd != -1)
443 			close(fd);
444 		if (*worktree != NULL)
445 			got_worktree_close(*worktree);
446 		*worktree = NULL;
447 	} else
448 		(*worktree)->lockfd = fd;
449 
450 	return err;
451 }
452 
453 const struct got_error *
454 got_worktree_open(struct got_worktree **worktree, const char *path)
455 {
456 	const struct got_error *err = NULL;
457 
458 	do {
459 		err = open_worktree(worktree, path);
460 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT))
461 			return err;
462 		if (*worktree)
463 			return NULL;
464 		path = dirname(path);
465 		if (path == NULL)
466 			return got_error_from_errno2("dirname", path);
467 	} while (!((path[0] == '.' || path[0] == '/') && path[1] == '\0'));
468 
469 	return got_error(GOT_ERR_NOT_WORKTREE);
470 }
471 
472 const struct got_error *
473 got_worktree_close(struct got_worktree *worktree)
474 {
475 	const struct got_error *err = NULL;
476 	free(worktree->root_path);
477 	free(worktree->repo_path);
478 	free(worktree->path_prefix);
479 	free(worktree->base_commit_id);
480 	free(worktree->head_ref_name);
481 	if (worktree->lockfd != -1)
482 		if (close(worktree->lockfd) != 0)
483 			err = got_error_from_errno2("close",
484 			    got_worktree_get_root_path(worktree));
485 	free(worktree);
486 	return err;
487 }
488 
489 const char *
490 got_worktree_get_root_path(struct got_worktree *worktree)
491 {
492 	return worktree->root_path;
493 }
494 
495 const char *
496 got_worktree_get_repo_path(struct got_worktree *worktree)
497 {
498 	return worktree->repo_path;
499 }
500 
501 const char *
502 got_worktree_get_path_prefix(struct got_worktree *worktree)
503 {
504 	return worktree->path_prefix;
505 }
506 
507 const struct got_error *
508 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
509     const char *path_prefix)
510 {
511 	char *absprefix = NULL;
512 
513 	if (!got_path_is_absolute(path_prefix)) {
514 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
515 			return got_error_from_errno("asprintf");
516 	}
517 	*match = (strcmp(absprefix ? absprefix : path_prefix,
518 	    worktree->path_prefix) == 0);
519 	free(absprefix);
520 	return NULL;
521 }
522 
523 const char *
524 got_worktree_get_head_ref_name(struct got_worktree *worktree)
525 {
526 	return worktree->head_ref_name;
527 }
528 
529 const struct got_error *
530 got_worktree_set_head_ref(struct got_worktree *worktree,
531     struct got_reference *head_ref)
532 {
533 	const struct got_error *err = NULL;
534 	char *path_got = NULL, *head_ref_name = NULL;
535 
536 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
537 	    GOT_WORKTREE_GOT_DIR) == -1) {
538 		err = got_error_from_errno("asprintf");
539 		path_got = NULL;
540 		goto done;
541 	}
542 
543 	head_ref_name = strdup(got_ref_get_name(head_ref));
544 	if (head_ref_name == NULL) {
545 		err = got_error_from_errno("strdup");
546 		goto done;
547 	}
548 
549 	err = write_head_ref(path_got, head_ref);
550 	if (err)
551 		goto done;
552 
553 	free(worktree->head_ref_name);
554 	worktree->head_ref_name = head_ref_name;
555 done:
556 	free(path_got);
557 	if (err)
558 		free(head_ref_name);
559 	return err;
560 }
561 
562 struct got_object_id *
563 got_worktree_get_base_commit_id(struct got_worktree *worktree)
564 {
565 	return worktree->base_commit_id;
566 }
567 
568 const struct got_error *
569 got_worktree_set_base_commit_id(struct got_worktree *worktree,
570     struct got_repository *repo, struct got_object_id *commit_id)
571 {
572 	const struct got_error *err;
573 	struct got_object *obj = NULL;
574 	char *id_str = NULL;
575 	char *path_got = NULL;
576 
577 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
578 	    GOT_WORKTREE_GOT_DIR) == -1) {
579 		err = got_error_from_errno("asprintf");
580 		path_got = NULL;
581 		goto done;
582 	}
583 
584 	err = got_object_open(&obj, repo, commit_id);
585 	if (err)
586 		return err;
587 
588 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
589 		err = got_error(GOT_ERR_OBJ_TYPE);
590 		goto done;
591 	}
592 
593 	/* Record our base commit. */
594 	err = got_object_id_str(&id_str, commit_id);
595 	if (err)
596 		goto done;
597 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
598 	if (err)
599 		goto done;
600 
601 	free(worktree->base_commit_id);
602 	worktree->base_commit_id = got_object_id_dup(commit_id);
603 	if (worktree->base_commit_id == NULL) {
604 		err = got_error_from_errno("got_object_id_dup");
605 		goto done;
606 	}
607 done:
608 	if (obj)
609 		got_object_close(obj);
610 	free(id_str);
611 	free(path_got);
612 	return err;
613 }
614 
615 static const struct got_error *
616 lock_worktree(struct got_worktree *worktree, int operation)
617 {
618 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
619 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
620 		    : got_error_from_errno2("flock",
621 		    got_worktree_get_root_path(worktree)));
622 	return NULL;
623 }
624 
625 static const struct got_error *
626 add_dir_on_disk(struct got_worktree *worktree, const char *path)
627 {
628 	const struct got_error *err = NULL;
629 	char *abspath;
630 
631 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
632 		return got_error_from_errno("asprintf");
633 
634 	err = got_path_mkdir(abspath);
635 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
636 		struct stat sb;
637 		err = NULL;
638 		if (lstat(abspath, &sb) == -1) {
639 			err = got_error_from_errno2("lstat", abspath);
640 		} else if (!S_ISDIR(sb.st_mode)) {
641 			/* TODO directory is obstructed; do something */
642 			err = got_error(GOT_ERR_FILE_OBSTRUCTED);
643 		}
644 	}
645 	free(abspath);
646 	return err;
647 }
648 
649 static const struct got_error *
650 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
651 {
652 	const struct got_error *err = NULL;
653 	uint8_t fbuf1[8192];
654 	uint8_t fbuf2[8192];
655 	size_t flen1 = 0, flen2 = 0;
656 
657 	*same = 1;
658 
659 	for (;;) {
660 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
661 		if (flen1 == 0 && ferror(f1)) {
662 			err = got_error_from_errno("fread");
663 			break;
664 		}
665 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
666 		if (flen2 == 0 && ferror(f2)) {
667 			err = got_error_from_errno("fread");
668 			break;
669 		}
670 		if (flen1 == 0) {
671 			if (flen2 != 0)
672 				*same = 0;
673 			break;
674 		} else if (flen2 == 0) {
675 			if (flen1 != 0)
676 				*same = 0;
677 			break;
678 		} else if (flen1 == flen2) {
679 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
680 				*same = 0;
681 				break;
682 			}
683 		} else {
684 			*same = 0;
685 			break;
686 		}
687 	}
688 
689 	return err;
690 }
691 
692 static const struct got_error *
693 check_files_equal(int *same, const char *f1_path, const char *f2_path)
694 {
695 	const struct got_error *err = NULL;
696 	struct stat sb;
697 	size_t size1, size2;
698 	FILE *f1 = NULL, *f2 = NULL;
699 
700 	*same = 1;
701 
702 	if (lstat(f1_path, &sb) != 0) {
703 		err = got_error_from_errno2("lstat", f1_path);
704 		goto done;
705 	}
706 	size1 = sb.st_size;
707 
708 	if (lstat(f2_path, &sb) != 0) {
709 		err = got_error_from_errno2("lstat", f2_path);
710 		goto done;
711 	}
712 	size2 = sb.st_size;
713 
714 	if (size1 != size2) {
715 		*same = 0;
716 		return NULL;
717 	}
718 
719 	f1 = fopen(f1_path, "r");
720 	if (f1 == NULL)
721 		return got_error_from_errno2("open", f1_path);
722 
723 	f2 = fopen(f2_path, "r");
724 	if (f2 == NULL) {
725 		err = got_error_from_errno2("open", f2_path);
726 		goto done;
727 	}
728 
729 	err = check_file_contents_equal(same, f1, f2);
730 done:
731 	if (f1 && fclose(f1) != 0 && err == NULL)
732 		err = got_error_from_errno("fclose");
733 	if (f2 && fclose(f2) != 0 && err == NULL)
734 		err = got_error_from_errno("fclose");
735 
736 	return err;
737 }
738 
739 /*
740  * Perform a 3-way merge where the file's version in the file index (blob2)
741  * acts as the common ancestor, the incoming blob (blob1) acts as the first
742  * derived version, and the file on disk acts as the second derived version.
743  */
744 static const struct got_error *
745 merge_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
746    struct got_fileindex_entry *ie, const char *ondisk_path, const char *path,
747    uint16_t te_mode, uint16_t st_mode, struct got_blob_object *blob1,
748    struct got_repository *repo,
749    got_worktree_checkout_cb progress_cb, void *progress_arg)
750 {
751 	const struct got_error *err = NULL;
752 	int merged_fd = -1;
753 	struct got_blob_object *blob2 = NULL;
754 	FILE *f1 = NULL, *f2 = NULL;
755 	char *blob1_path = NULL, *blob2_path = NULL;
756 	char *merged_path = NULL, *base_path = NULL;
757 	char *id_str = NULL;
758 	char *label1 = NULL;
759 	int overlapcnt = 0, update_timestamps = 0;
760 	char *parent;
761 
762 	parent = dirname(ondisk_path);
763 	if (parent == NULL)
764 		return got_error_from_errno2("dirname", ondisk_path);
765 
766 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
767 		return got_error_from_errno("asprintf");
768 
769 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
770 	if (err)
771 		goto done;
772 
773 	free(base_path);
774 	if (asprintf(&base_path, "%s/got-merge-blob1", parent) == -1) {
775 		err = got_error_from_errno("asprintf");
776 		base_path = NULL;
777 		goto done;
778 	}
779 
780 	err = got_opentemp_named(&blob1_path, &f1, base_path);
781 	if (err)
782 		goto done;
783 	err = got_object_blob_dump_to_file(NULL, NULL, f1, blob1);
784 	if (err)
785 		goto done;
786 
787 	free(base_path);
788 	if (asprintf(&base_path, "%s/got-merge-blob2", parent) == -1) {
789 		err = got_error_from_errno("asprintf");
790 		base_path = NULL;
791 		goto done;
792 	}
793 
794 	err = got_opentemp_named(&blob2_path, &f2, base_path);
795 	if (err)
796 		goto done;
797 	if (got_fileindex_entry_has_blob(ie)) {
798 		struct got_object_id id2;
799 		memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
800 		err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
801 		if (err)
802 			goto done;
803 		err = got_object_blob_dump_to_file(NULL, NULL, f2, blob2);
804 		if (err)
805 			goto done;
806 	} else {
807 		/*
808 		 * If the file has no blob, this is an "add vs add" conflict,
809 		 * and we simply use an empty ancestor file to make both files
810 		 * appear in the merged result in their entirety.
811 		 */
812 	}
813 
814 	err = got_object_id_str(&id_str, worktree->base_commit_id);
815 	if (err)
816 		goto done;
817 	if (asprintf(&label1, "commit %s", id_str) == -1) {
818 		err = got_error_from_errno("asprintf");
819 		goto done;
820 	}
821 
822 	err = got_merge_diff3(&overlapcnt, merged_fd, blob1_path,
823 	    blob2_path, ondisk_path, label1, path);
824 	if (err)
825 		goto done;
826 
827 	(*progress_cb)(progress_arg,
828 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
829 
830 	if (fsync(merged_fd) != 0) {
831 		err = got_error_from_errno("fsync");
832 		goto done;
833 	}
834 
835 	/* Check if a clean merge has subsumed all local changes. */
836 	if (overlapcnt == 0) {
837 		err = check_files_equal(&update_timestamps, blob1_path,
838 		    merged_path);
839 		if (err)
840 			goto done;
841 	}
842 
843 	if (chmod(merged_path, st_mode) != 0) {
844 		err = got_error_from_errno2("chmod", merged_path);
845 		goto done;
846 	}
847 
848 	if (rename(merged_path, ondisk_path) != 0) {
849 		err = got_error_from_errno3("rename", merged_path,
850 		    ondisk_path);
851 		unlink(merged_path);
852 		goto done;
853 	}
854 
855 	/*
856 	 * Do not update timestamps of already modified files. Otherwise,
857 	 * a future status walk would treat them as unmodified files again.
858 	 */
859 	err = got_fileindex_entry_update(ie, ondisk_path,
860 	    blob1->id.sha1, worktree->base_commit_id->sha1, update_timestamps);
861 done:
862 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
863 		err = got_error_from_errno("close");
864 	if (f1 && fclose(f1) != 0 && err == NULL)
865 		err = got_error_from_errno("fclose");
866 	if (f2 && fclose(f2) != 0 && err == NULL)
867 		err = got_error_from_errno("fclose");
868 	if (blob2)
869 		got_object_blob_close(blob2);
870 	free(merged_path);
871 	free(base_path);
872 	if (blob1_path) {
873 		unlink(blob1_path);
874 		free(blob1_path);
875 	}
876 	if (blob2_path) {
877 		unlink(blob2_path);
878 		free(blob2_path);
879 	}
880 	free(id_str);
881 	free(label1);
882 	return err;
883 }
884 
885 static const struct got_error *
886 update_blob_fileindex_entry(struct got_worktree *worktree,
887     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
888     const char *ondisk_path, const char *path, struct got_blob_object *blob,
889     int update_timestamps)
890 {
891 	const struct got_error *err = NULL;
892 
893 	if (ie == NULL)
894 		ie = got_fileindex_entry_get(fileindex, path);
895 	if (ie)
896 		err = got_fileindex_entry_update(ie, ondisk_path,
897 		    blob->id.sha1, worktree->base_commit_id->sha1,
898 		    update_timestamps);
899 	else {
900 		struct got_fileindex_entry *new_ie;
901 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
902 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
903 		if (!err)
904 			err = got_fileindex_entry_add(fileindex, new_ie);
905 	}
906 	return err;
907 }
908 
909 static const struct got_error *
910 install_blob(struct got_worktree *worktree, const char *ondisk_path,
911    const char *path, uint16_t te_mode, uint16_t st_mode,
912    struct got_blob_object *blob, int restoring_missing_file,
913    int reverting_versioned_file, struct got_repository *repo,
914    got_worktree_checkout_cb progress_cb, void *progress_arg)
915 {
916 	const struct got_error *err = NULL;
917 	int fd = -1;
918 	size_t len, hdrlen;
919 	int update = 0;
920 	char *tmppath = NULL;
921 
922 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
923 	    GOT_DEFAULT_FILE_MODE);
924 	if (fd == -1) {
925 		if (errno == ENOENT) {
926 			char *parent = dirname(path);
927 			if (parent == NULL)
928 				return got_error_from_errno2("dirname", path);
929 			err = add_dir_on_disk(worktree, parent);
930 			if (err)
931 				return err;
932 			fd = open(ondisk_path,
933 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
934 			    GOT_DEFAULT_FILE_MODE);
935 			if (fd == -1)
936 				return got_error_from_errno2("open",
937 				    ondisk_path);
938 		} else if (errno == EEXIST) {
939 			if (!S_ISREG(st_mode)) {
940 				/* TODO file is obstructed; do something */
941 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
942 				goto done;
943 			} else {
944 				err = got_opentemp_named_fd(&tmppath, &fd,
945 				    ondisk_path);
946 				if (err)
947 					goto done;
948 				update = 1;
949 			}
950 		} else
951 			return got_error_from_errno2("open", ondisk_path);
952 	}
953 
954 	if (restoring_missing_file)
955 		(*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
956 	else if (reverting_versioned_file)
957 		(*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
958 	else
959 		(*progress_cb)(progress_arg,
960 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
961 
962 	hdrlen = got_object_blob_get_hdrlen(blob);
963 	do {
964 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
965 		err = got_object_blob_read_block(&len, blob);
966 		if (err)
967 			break;
968 		if (len > 0) {
969 			/* Skip blob object header first time around. */
970 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
971 			if (outlen == -1) {
972 				err = got_error_from_errno("write");
973 				goto done;
974 			} else if (outlen != len - hdrlen) {
975 				err = got_error(GOT_ERR_IO);
976 				goto done;
977 			}
978 			hdrlen = 0;
979 		}
980 	} while (len != 0);
981 
982 	if (fsync(fd) != 0) {
983 		err = got_error_from_errno("fsync");
984 		goto done;
985 	}
986 
987 	if (update) {
988 		if (rename(tmppath, ondisk_path) != 0) {
989 			err = got_error_from_errno3("rename", tmppath,
990 			    ondisk_path);
991 			unlink(tmppath);
992 			goto done;
993 		}
994 	}
995 
996 	if (te_mode & S_IXUSR) {
997 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
998 			err = got_error_from_errno2("chmod", ondisk_path);
999 			goto done;
1000 		}
1001 	} else {
1002 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
1003 			err = got_error_from_errno2("chmod", ondisk_path);
1004 			goto done;
1005 		}
1006 	}
1007 
1008 done:
1009 	if (fd != -1 && close(fd) != 0 && err == NULL)
1010 		err = got_error_from_errno("close");
1011 	free(tmppath);
1012 	return err;
1013 }
1014 
1015 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
1016 static const struct got_error *
1017 get_modified_file_content_status(unsigned char *status, FILE *f)
1018 {
1019 	const struct got_error *err = NULL;
1020 	const char *markers[3] = {
1021 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
1022 		GOT_DIFF_CONFLICT_MARKER_SEP,
1023 		GOT_DIFF_CONFLICT_MARKER_END
1024 	};
1025 	int i = 0;
1026 	char *line;
1027 	size_t len;
1028 	const char delim[3] = {'\0', '\0', '\0'};
1029 
1030 	while (*status == GOT_STATUS_MODIFY) {
1031 		line = fparseln(f, &len, NULL, delim, 0);
1032 		if (line == NULL) {
1033 			if (feof(f))
1034 				break;
1035 			err = got_ferror(f, GOT_ERR_IO);
1036 			break;
1037 		}
1038 
1039 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1040 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1041 			    == 0)
1042 				*status = GOT_STATUS_CONFLICT;
1043 			else
1044 				i++;
1045 		}
1046 	}
1047 
1048 	return err;
1049 }
1050 
1051 static const struct got_error *
1052 get_file_status(unsigned char *status, struct stat *sb,
1053     struct got_fileindex_entry *ie, const char *abspath,
1054     struct got_repository *repo)
1055 {
1056 	const struct got_error *err = NULL;
1057 	struct got_object_id id;
1058 	size_t hdrlen;
1059 	FILE *f = NULL;
1060 	uint8_t fbuf[8192];
1061 	struct got_blob_object *blob = NULL;
1062 	size_t flen, blen;
1063 
1064 	*status = GOT_STATUS_NO_CHANGE;
1065 
1066 	if (lstat(abspath, sb) == -1) {
1067 		if (errno == ENOENT) {
1068 			if (ie) {
1069 				if (got_fileindex_entry_has_file_on_disk(ie))
1070 					*status = GOT_STATUS_MISSING;
1071 				else
1072 					*status = GOT_STATUS_DELETE;
1073 				sb->st_mode =
1074 				    ((ie->mode >> GOT_FILEIDX_MODE_PERMS_SHIFT)
1075 				    & (S_IRWXU | S_IRWXG | S_IRWXO));
1076 			} else
1077 				sb->st_mode = GOT_DEFAULT_FILE_MODE;
1078 			return NULL;
1079 		}
1080 		return got_error_from_errno2("lstat", abspath);
1081 	}
1082 
1083 	if (!S_ISREG(sb->st_mode)) {
1084 		*status = GOT_STATUS_OBSTRUCTED;
1085 		return NULL;
1086 	}
1087 
1088 	if (ie == NULL)
1089 		return NULL;
1090 
1091 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1092 		*status = GOT_STATUS_DELETE;
1093 		return NULL;
1094 	} else if (!got_fileindex_entry_has_blob(ie)) {
1095 		*status = GOT_STATUS_ADD;
1096 		return NULL;
1097 	}
1098 
1099 	if (ie->ctime_sec == sb->st_ctime &&
1100 	    ie->ctime_nsec == sb->st_ctimensec &&
1101 	    ie->mtime_sec == sb->st_mtime &&
1102 	    ie->mtime_sec == sb->st_mtime &&
1103 	    ie->mtime_nsec == sb->st_mtimensec &&
1104 	    ie->size == (sb->st_size & 0xffffffff))
1105 		return NULL;
1106 
1107 	memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1108 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1109 	if (err)
1110 		return err;
1111 
1112 	f = fopen(abspath, "r");
1113 	if (f == NULL) {
1114 		err = got_error_from_errno2("fopen", abspath);
1115 		goto done;
1116 	}
1117 	hdrlen = got_object_blob_get_hdrlen(blob);
1118 	for (;;) {
1119 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1120 		err = got_object_blob_read_block(&blen, blob);
1121 		if (err)
1122 			goto done;
1123 		/* Skip length of blob object header first time around. */
1124 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1125 		if (flen == 0 && ferror(f)) {
1126 			err = got_error_from_errno("fread");
1127 			goto done;
1128 		}
1129 		if (blen == 0) {
1130 			if (flen != 0)
1131 				*status = GOT_STATUS_MODIFY;
1132 			break;
1133 		} else if (flen == 0) {
1134 			if (blen != 0)
1135 				*status = GOT_STATUS_MODIFY;
1136 			break;
1137 		} else if (blen - hdrlen == flen) {
1138 			/* Skip blob object header first time around. */
1139 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1140 				*status = GOT_STATUS_MODIFY;
1141 				break;
1142 			}
1143 		} else {
1144 			*status = GOT_STATUS_MODIFY;
1145 			break;
1146 		}
1147 		hdrlen = 0;
1148 	}
1149 
1150 	if (*status == GOT_STATUS_MODIFY) {
1151 		rewind(f);
1152 		err = get_modified_file_content_status(status, f);
1153 	}
1154 done:
1155 	if (blob)
1156 		got_object_blob_close(blob);
1157 	if (f)
1158 		fclose(f);
1159 	return err;
1160 }
1161 
1162 static const struct got_error *
1163 update_blob(struct got_worktree *worktree,
1164     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1165     struct got_tree_entry *te, const char *path,
1166     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1167     void *progress_arg)
1168 {
1169 	const struct got_error *err = NULL;
1170 	struct got_blob_object *blob = NULL;
1171 	char *ondisk_path;
1172 	unsigned char status = GOT_STATUS_NO_CHANGE;
1173 	struct stat sb;
1174 
1175 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1176 		return got_error_from_errno("asprintf");
1177 
1178 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1179 	if (err)
1180 		goto done;
1181 
1182 	if (status == GOT_STATUS_OBSTRUCTED) {
1183 		(*progress_cb)(progress_arg, status, path);
1184 		goto done;
1185 	}
1186 
1187 	if (ie && status != GOT_STATUS_MISSING) {
1188 		if (got_fileindex_entry_has_commit(ie) &&
1189 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1190 		    SHA1_DIGEST_LENGTH) == 0) {
1191 			(*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1192 			    path);
1193 			goto done;
1194 		}
1195 		if (got_fileindex_entry_has_blob(ie) &&
1196 		    memcmp(ie->blob_sha1, te->id->sha1,
1197 		    SHA1_DIGEST_LENGTH) == 0)
1198 			goto done;
1199 	}
1200 
1201 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1202 	if (err)
1203 		goto done;
1204 
1205 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD)
1206 		err = merge_blob(worktree, fileindex, ie, ondisk_path, path,
1207 		    te->mode, sb.st_mode, blob, repo, progress_cb,
1208 		    progress_arg);
1209 	else if (status == GOT_STATUS_DELETE) {
1210 		(*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1211 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1212 		    ondisk_path, path, blob, 0);
1213 		if (err)
1214 			goto done;
1215 	} else {
1216 		err = install_blob(worktree, ondisk_path, path, te->mode,
1217 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1218 		    repo, progress_cb, progress_arg);
1219 		if (err)
1220 			goto done;
1221 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1222 		    ondisk_path, path, blob, 1);
1223 		if (err)
1224 			goto done;
1225 	}
1226 	got_object_blob_close(blob);
1227 done:
1228 	free(ondisk_path);
1229 	return err;
1230 }
1231 
1232 static const struct got_error *
1233 remove_ondisk_file(const char *root_path, const char *path)
1234 {
1235 	const struct got_error *err = NULL;
1236 	char *ondisk_path = NULL;
1237 
1238 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1239 		return got_error_from_errno("asprintf");
1240 
1241 	if (unlink(ondisk_path) == -1) {
1242 		if (errno != ENOENT)
1243 			err = got_error_from_errno2("unlink", ondisk_path);
1244 	} else {
1245 		char *parent = dirname(ondisk_path);
1246 		while (parent && strcmp(parent, root_path) != 0) {
1247 			if (rmdir(parent) == -1) {
1248 				if (errno != ENOTEMPTY)
1249 					err = got_error_from_errno2("rmdir",
1250 					    parent);
1251 				break;
1252 			}
1253 			parent = dirname(parent);
1254 		}
1255 	}
1256 	free(ondisk_path);
1257 	return err;
1258 }
1259 
1260 static const struct got_error *
1261 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1262     struct got_fileindex_entry *ie, const char *parent_path,
1263     struct got_repository *repo,
1264     got_worktree_checkout_cb progress_cb, void *progress_arg)
1265 {
1266 	const struct got_error *err = NULL;
1267 	unsigned char status;
1268 	struct stat sb;
1269 	char *ondisk_path;
1270 
1271 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1272 	    == -1)
1273 		return got_error_from_errno("asprintf");
1274 
1275 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1276 	if (err)
1277 		return err;
1278 
1279 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1280 	    status == GOT_STATUS_ADD) {
1281 		(*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1282 		/*
1283 		 * Preserve the working file and change the deleted blob's
1284 		 * entry into a schedule-add entry.
1285 		 */
1286 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1287 		    0);
1288 		if (err)
1289 			return err;
1290 	} else {
1291 		(*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1292 		if (status == GOT_STATUS_NO_CHANGE) {
1293 			err = remove_ondisk_file(worktree->root_path, ie->path);
1294 			if (err)
1295 				return err;
1296 		}
1297 		got_fileindex_entry_remove(fileindex, ie);
1298 	}
1299 
1300 	return err;
1301 }
1302 
1303 struct diff_cb_arg {
1304     struct got_fileindex *fileindex;
1305     struct got_worktree *worktree;
1306     struct got_repository *repo;
1307     got_worktree_checkout_cb progress_cb;
1308     void *progress_arg;
1309     got_worktree_cancel_cb cancel_cb;
1310     void *cancel_arg;
1311 };
1312 
1313 static const struct got_error *
1314 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1315     struct got_tree_entry *te, 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 update_blob(a->worktree, a->fileindex, ie, te,
1323 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1324 }
1325 
1326 static const struct got_error *
1327 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1328 {
1329 	struct diff_cb_arg *a = arg;
1330 
1331 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1332 		return got_error(GOT_ERR_CANCELLED);
1333 
1334 	return delete_blob(a->worktree, a->fileindex, ie, parent_path,
1335 	    a->repo, a->progress_cb, a->progress_arg);
1336 }
1337 
1338 static const struct got_error *
1339 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1340 {
1341 	struct diff_cb_arg *a = arg;
1342 	const struct got_error *err;
1343 	char *path;
1344 
1345 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1346 		return got_error(GOT_ERR_CANCELLED);
1347 
1348 	if (asprintf(&path, "%s%s%s", parent_path,
1349 	    parent_path[0] ? "/" : "", te->name)
1350 	    == -1)
1351 		return got_error_from_errno("asprintf");
1352 
1353 	if (S_ISDIR(te->mode))
1354 		err = add_dir_on_disk(a->worktree, path);
1355 	else
1356 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1357 		    a->repo, a->progress_cb, a->progress_arg);
1358 
1359 	free(path);
1360 	return err;
1361 }
1362 
1363 const struct got_error *
1364 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1365 {
1366 	const struct got_error *err = NULL;
1367 	char *uuidstr = NULL;
1368 	uint32_t uuid_status;
1369 
1370 	*refname = NULL;
1371 
1372 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1373 	if (uuid_status != uuid_s_ok)
1374 		return got_error_uuid(uuid_status);
1375 
1376 	if (asprintf(refname, "%s-%s", GOT_WORKTREE_BASE_REF_PREFIX, uuidstr)
1377 	    == -1) {
1378 		err = got_error_from_errno("asprintf");
1379 		*refname = NULL;
1380 	}
1381 	free(uuidstr);
1382 	return err;
1383 }
1384 
1385 /*
1386  * Prevent Git's garbage collector from deleting our base commit by
1387  * setting a reference to our base commit's ID.
1388  */
1389 static const struct got_error *
1390 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1391 {
1392 	const struct got_error *err = NULL;
1393 	struct got_reference *ref = NULL;
1394 	char *refname;
1395 
1396 	err = got_worktree_get_base_ref_name(&refname, worktree);
1397 	if (err)
1398 		return err;
1399 
1400 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1401 	if (err)
1402 		goto done;
1403 
1404 	err = got_ref_write(ref, repo);
1405 done:
1406 	free(refname);
1407 	if (ref)
1408 		got_ref_close(ref);
1409 	return err;
1410 }
1411 
1412 static const struct got_error *
1413 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1414    struct got_worktree *worktree)
1415 {
1416 	const struct got_error *err = NULL;
1417 	FILE *index = NULL;
1418 
1419 	*fileindex_path = NULL;
1420 	*fileindex = got_fileindex_alloc();
1421 	if (*fileindex == NULL)
1422 		return got_error_from_errno("got_fileindex_alloc");
1423 
1424 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1425 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1426 		err = got_error_from_errno("asprintf");
1427 		*fileindex_path = NULL;
1428 		goto done;
1429 	}
1430 
1431 	index = fopen(*fileindex_path, "rb");
1432 	if (index == NULL) {
1433 		if (errno != ENOENT)
1434 			err = got_error_from_errno2("fopen", *fileindex_path);
1435 	} else {
1436 		err = got_fileindex_read(*fileindex, index);
1437 		if (fclose(index) != 0 && err == NULL)
1438 			err = got_error_from_errno("fclose");
1439 	}
1440 done:
1441 	if (err) {
1442 		free(*fileindex_path);
1443 		*fileindex_path = NULL;
1444 		free(*fileindex);
1445 		*fileindex = NULL;
1446 	}
1447 	return err;
1448 }
1449 
1450 struct bump_base_commit_id_arg {
1451 	struct got_object_id *base_commit_id;
1452 	const char *path;
1453 	size_t path_len;
1454 	const char *entry_name;
1455 };
1456 
1457 /* Bump base commit ID of all files within an updated part of the work tree. */
1458 static const struct got_error *
1459 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1460 {
1461 	struct bump_base_commit_id_arg *a = arg;
1462 
1463 	if (a->entry_name) {
1464 		if (strcmp(ie->path, a->path) != 0)
1465 			return NULL;
1466 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1467 		return NULL;
1468 
1469 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1470 	return NULL;
1471 }
1472 
1473 const struct got_error *
1474 got_worktree_checkout_files(struct got_worktree *worktree, const char *path,
1475     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1476     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1477 {
1478 	const struct got_error *err = NULL, *unlockerr, *checkout_err = NULL;
1479 	struct got_commit_object *commit = NULL;
1480 	struct got_object_id *tree_id = NULL;
1481 	struct got_tree_object *tree = NULL;
1482 	char *fileindex_path = NULL, *new_fileindex_path = NULL;
1483 	struct got_fileindex *fileindex = NULL;
1484 	FILE *new_index = NULL;
1485 	struct got_fileindex_diff_tree_cb diff_cb;
1486 	struct diff_cb_arg arg;
1487 	char *relpath = NULL, *entry_name = NULL;
1488 
1489 	err = lock_worktree(worktree, LOCK_EX);
1490 	if (err)
1491 		return err;
1492 
1493 	/*
1494 	 * Read the file index.
1495 	 * Checking out files is supposed to be an idempotent operation.
1496 	 * If the on-disk file index is incomplete we will try to complete it.
1497 	 */
1498 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1499 	if (err)
1500 		goto done;
1501 
1502 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1503 	    fileindex_path);
1504 	if (err)
1505 		goto done;
1506 
1507 	err = ref_base_commit(worktree, repo);
1508 	if (err)
1509 		goto done;
1510 
1511 	err = got_object_open_as_commit(&commit, repo,
1512 	   worktree->base_commit_id);
1513 	if (err)
1514 		goto done;
1515 
1516 	if (path[0]) {
1517 		char *tree_path;
1518 		int obj_type;
1519 		relpath = strdup(path);
1520 		if (relpath == NULL) {
1521 			err = got_error_from_errno("strdup");
1522 			goto done;
1523 		}
1524 		if (asprintf(&tree_path, "%s%s%s", worktree->path_prefix,
1525 		    got_path_is_root_dir(worktree->path_prefix) ? "" : "/",
1526 		    path) == -1) {
1527 			err = got_error_from_errno("asprintf");
1528 			goto done;
1529 		}
1530 		err = got_object_id_by_path(&tree_id, repo,
1531 		    worktree->base_commit_id, tree_path);
1532 		free(tree_path);
1533 		if (err)
1534 			goto done;
1535 		err = got_object_get_type(&obj_type, repo, tree_id);
1536 		if (err)
1537 			goto done;
1538 		if (obj_type == GOT_OBJ_TYPE_BLOB) {
1539 			/* Split provided path into parent dir + entry name. */
1540 			if (strchr(path, '/')  == NULL) {
1541 				relpath = strdup("");
1542 				if (relpath == NULL) {
1543 					err = got_error_from_errno("strdup");
1544 					goto done;
1545 				}
1546 				tree_path = strdup(worktree->path_prefix);
1547 				if (tree_path == NULL) {
1548 					err = got_error_from_errno("strdup");
1549 					goto done;
1550 				}
1551 			} else {
1552 				err = got_path_dirname(&relpath, path);
1553 				if (err)
1554 					goto done;
1555 				if (asprintf(&tree_path, "%s%s%s",
1556 				    worktree->path_prefix,
1557 				    got_path_is_root_dir(
1558 				    worktree->path_prefix) ? "" : "/",
1559 				    relpath) == -1) {
1560 					err = got_error_from_errno("asprintf");
1561 					goto done;
1562 				}
1563 			}
1564 			err = got_object_id_by_path(&tree_id, repo,
1565 			    worktree->base_commit_id, tree_path);
1566 			free(tree_path);
1567 			if (err)
1568 				goto done;
1569 			entry_name = basename(path);
1570 			if (entry_name == NULL) {
1571 				err = got_error_from_errno2("basename", path);
1572 				goto done;
1573 			}
1574 		}
1575 	} else {
1576 		relpath = strdup("");
1577 		if (relpath == NULL) {
1578 			err = got_error_from_errno("strdup");
1579 			goto done;
1580 		}
1581 		err = got_object_id_by_path(&tree_id, repo,
1582 		    worktree->base_commit_id, worktree->path_prefix);
1583 		if (err)
1584 			goto done;
1585 	}
1586 
1587 	err = got_object_open_as_tree(&tree, repo, tree_id);
1588 	if (err)
1589 		goto done;
1590 
1591 	if (entry_name &&
1592 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1593 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1594 		goto done;
1595 	}
1596 
1597 	diff_cb.diff_old_new = diff_old_new;
1598 	diff_cb.diff_old = diff_old;
1599 	diff_cb.diff_new = diff_new;
1600 	arg.fileindex = fileindex;
1601 	arg.worktree = worktree;
1602 	arg.repo = repo;
1603 	arg.progress_cb = progress_cb;
1604 	arg.progress_arg = progress_arg;
1605 	arg.cancel_cb = cancel_cb;
1606 	arg.cancel_arg = cancel_arg;
1607 	checkout_err = got_fileindex_diff_tree(fileindex, tree, relpath,
1608 	    entry_name, repo, &diff_cb, &arg);
1609 
1610 	if (checkout_err == NULL) {
1611 		struct bump_base_commit_id_arg bbc_arg;
1612 		bbc_arg.base_commit_id = worktree->base_commit_id;
1613 		bbc_arg.entry_name = entry_name;
1614 		bbc_arg.path = path;
1615 		bbc_arg.path_len = strlen(path);
1616 		err = got_fileindex_for_each_entry_safe(fileindex,
1617 		    bump_base_commit_id, &bbc_arg);
1618 		if (err)
1619 			goto done;
1620 	}
1621 
1622 	/* Try to sync the fileindex back to disk in any case. */
1623 	err = got_fileindex_write(fileindex, new_index);
1624 	if (err)
1625 		goto done;
1626 
1627 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1628 		err = got_error_from_errno3("rename", new_fileindex_path,
1629 		    fileindex_path);
1630 		unlink(new_fileindex_path);
1631 		goto done;
1632 	}
1633 
1634 	free(new_fileindex_path);
1635 	new_fileindex_path = NULL;
1636 
1637 done:
1638 	free(relpath);
1639 	if (tree)
1640 		got_object_tree_close(tree);
1641 	if (commit)
1642 		got_object_commit_close(commit);
1643 	if (new_fileindex_path)
1644 		unlink(new_fileindex_path);
1645 	if (new_index)
1646 		fclose(new_index);
1647 	free(new_fileindex_path);
1648 	free(fileindex_path);
1649 	got_fileindex_free(fileindex);
1650 	if (checkout_err)
1651 		err = checkout_err;
1652 	unlockerr = lock_worktree(worktree, LOCK_SH);
1653 	if (unlockerr && err == NULL)
1654 		err = unlockerr;
1655 	return err;
1656 }
1657 
1658 struct diff_dir_cb_arg {
1659     struct got_fileindex *fileindex;
1660     struct got_worktree *worktree;
1661     const char *status_path;
1662     size_t status_path_len;
1663     struct got_repository *repo;
1664     got_worktree_status_cb status_cb;
1665     void *status_arg;
1666     got_worktree_cancel_cb cancel_cb;
1667     void *cancel_arg;
1668 };
1669 
1670 static const struct got_error *
1671 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
1672     got_worktree_status_cb status_cb, void *status_arg,
1673     struct got_repository *repo)
1674 {
1675 	const struct got_error *err = NULL;
1676 	unsigned char status = GOT_STATUS_NO_CHANGE;
1677 	struct stat sb;
1678 	struct got_object_id blob_id, commit_id;
1679 
1680 	err = get_file_status(&status, &sb, ie, abspath, repo);
1681 	if (err == NULL && status != GOT_STATUS_NO_CHANGE) {
1682 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1683 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
1684 		err = (*status_cb)(status_arg, status, ie->path, &blob_id,
1685 		    &commit_id);
1686 	}
1687 	return err;
1688 }
1689 
1690 static const struct got_error *
1691 status_old_new(void *arg, struct got_fileindex_entry *ie,
1692     struct dirent *de, const char *parent_path)
1693 {
1694 	const struct got_error *err = NULL;
1695 	struct diff_dir_cb_arg *a = arg;
1696 	char *abspath;
1697 
1698 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1699 		return got_error(GOT_ERR_CANCELLED);
1700 
1701 	if (got_path_cmp(parent_path, a->status_path) != 0 &&
1702 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
1703 		return NULL;
1704 
1705 	if (parent_path[0]) {
1706 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
1707 		    parent_path, de->d_name) == -1)
1708 			return got_error_from_errno("asprintf");
1709 	} else {
1710 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
1711 		    de->d_name) == -1)
1712 			return got_error_from_errno("asprintf");
1713 	}
1714 
1715 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
1716 	    a->repo);
1717 	free(abspath);
1718 	return err;
1719 }
1720 
1721 static const struct got_error *
1722 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1723 {
1724 	struct diff_dir_cb_arg *a = arg;
1725 	struct got_object_id blob_id, commit_id;
1726 	unsigned char status;
1727 
1728 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1729 		return got_error(GOT_ERR_CANCELLED);
1730 
1731 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
1732 		return NULL;
1733 
1734 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1735 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
1736 	if (got_fileindex_entry_has_file_on_disk(ie))
1737 		status = GOT_STATUS_MISSING;
1738 	else
1739 		status = GOT_STATUS_DELETE;
1740 	return (*a->status_cb)(a->status_arg, status, ie->path, &blob_id,
1741 	    &commit_id);
1742 }
1743 
1744 static const struct got_error *
1745 status_new(void *arg, struct dirent *de, const char *parent_path)
1746 {
1747 	const struct got_error *err = NULL;
1748 	struct diff_dir_cb_arg *a = arg;
1749 	char *path = NULL;
1750 
1751 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1752 		return got_error(GOT_ERR_CANCELLED);
1753 
1754 	if (de->d_type == DT_DIR)
1755 		return NULL;
1756 
1757 	/* XXX ignore symlinks for now */
1758 	if (de->d_type == DT_LNK)
1759 		return NULL;
1760 
1761 	if (!got_path_is_child(parent_path, a->status_path, a->status_path_len))
1762 		return NULL;
1763 
1764 	if (parent_path[0]) {
1765 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
1766 			return got_error_from_errno("asprintf");
1767 	} else {
1768 		path = de->d_name;
1769 	}
1770 
1771 	err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED, path,
1772 	    NULL, NULL);
1773 	if (parent_path[0])
1774 		free(path);
1775 	return err;
1776 }
1777 
1778 const struct got_error *
1779 got_worktree_status(struct got_worktree *worktree, const char *path,
1780     struct got_repository *repo, got_worktree_status_cb status_cb,
1781     void *status_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1782 {
1783 	const struct got_error *err = NULL;
1784 	DIR *workdir = NULL;
1785 	char *fileindex_path = NULL;
1786 	struct got_fileindex *fileindex = NULL;
1787 	FILE *index = NULL;
1788 	struct got_fileindex_diff_dir_cb fdiff_cb;
1789 	struct diff_dir_cb_arg arg;
1790 	char *ondisk_path = NULL;
1791 
1792 	fileindex = got_fileindex_alloc();
1793 	if (fileindex == NULL) {
1794 		err = got_error_from_errno("got_fileindex_alloc");
1795 		goto done;
1796 	}
1797 
1798 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
1799 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1800 		err = got_error_from_errno("asprintf");
1801 		fileindex_path = NULL;
1802 		goto done;
1803 	}
1804 
1805 	index = fopen(fileindex_path, "rb");
1806 	if (index == NULL) {
1807 		if (errno != ENOENT) {
1808 			err = got_error_from_errno2("fopen", fileindex_path);
1809 			goto done;
1810 		}
1811 	} else {
1812 		err = got_fileindex_read(fileindex, index);
1813 		fclose(index);
1814 		if (err)
1815 			goto done;
1816 	}
1817 
1818 	if (asprintf(&ondisk_path, "%s%s%s",
1819 	    worktree->root_path, path[0] ? "/" : "", path) == -1) {
1820 		err = got_error_from_errno("asprintf");
1821 		goto done;
1822 	}
1823 	workdir = opendir(ondisk_path);
1824 	if (workdir == NULL) {
1825 		if (errno == ENOTDIR || errno == ENOENT) {
1826 			struct got_fileindex_entry *ie;
1827 			ie = got_fileindex_entry_get(fileindex, path);
1828 			if (ie == NULL) {
1829 				err = got_error(GOT_ERR_BAD_PATH);
1830 				goto done;
1831 			}
1832 			err = report_file_status(ie, ondisk_path,
1833 			    status_cb, status_arg, repo);
1834 			goto done;
1835 		} else {
1836 			err = got_error_from_errno2("opendir", ondisk_path);
1837 			goto done;
1838 		}
1839 	}
1840 	fdiff_cb.diff_old_new = status_old_new;
1841 	fdiff_cb.diff_old = status_old;
1842 	fdiff_cb.diff_new = status_new;
1843 	arg.fileindex = fileindex;
1844 	arg.worktree = worktree;
1845 	arg.status_path = path;
1846 	arg.status_path_len = strlen(path);
1847 	arg.repo = repo;
1848 	arg.status_cb = status_cb;
1849 	arg.status_arg = status_arg;
1850 	arg.cancel_cb = cancel_cb;
1851 	arg.cancel_arg = cancel_arg;
1852 	err = got_fileindex_diff_dir(fileindex, workdir, worktree->root_path,
1853 	    path, repo, &fdiff_cb, &arg);
1854 done:
1855 	if (workdir)
1856 		closedir(workdir);
1857 	free(ondisk_path);
1858 	free(fileindex_path);
1859 	got_fileindex_free(fileindex);
1860 	return err;
1861 }
1862 
1863 const struct got_error *
1864 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
1865     const char *arg)
1866 {
1867 	const struct got_error *err = NULL;
1868 	char *resolved, *path = NULL;
1869 	size_t len;
1870 
1871 	*wt_path = NULL;
1872 
1873 	resolved = realpath(arg, NULL);
1874 	if (resolved == NULL)
1875 		return got_error_from_errno2("realpath", arg);
1876 
1877 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
1878 	    strlen(got_worktree_get_root_path(worktree)))) {
1879 		err = got_error(GOT_ERR_BAD_PATH);
1880 		goto done;
1881 	}
1882 
1883 	path = strdup(resolved +
1884 	    strlen(got_worktree_get_root_path(worktree)) + 1 /* skip '/' */);
1885 	if (path == NULL) {
1886 		err = got_error_from_errno("strdup");
1887 		goto done;
1888 	}
1889 
1890 	/* XXX status walk can't deal with trailing slash! */
1891 	len = strlen(path);
1892 	while (path[len - 1] == '/') {
1893 		path[len - 1] = '\0';
1894 		len--;
1895 	}
1896 done:
1897 	free(resolved);
1898 	if (err == NULL)
1899 		*wt_path = path;
1900 	else
1901 		free(path);
1902 	return err;
1903 }
1904 
1905 const struct got_error *
1906 got_worktree_schedule_add(struct got_worktree *worktree,
1907     struct got_pathlist_head *ondisk_paths,
1908     got_worktree_status_cb status_cb, void *status_arg,
1909     struct got_repository *repo)
1910 {
1911 	struct got_fileindex *fileindex = NULL;
1912 	char *fileindex_path = NULL, *new_fileindex_path = NULL;
1913 	FILE *index = NULL, *new_index = NULL;
1914 	const struct got_error *err = NULL, *unlockerr = NULL;
1915 	struct got_pathlist_entry *pe;
1916 
1917 	err = lock_worktree(worktree, LOCK_EX);
1918 	if (err)
1919 		return err;
1920 
1921 
1922 	fileindex = got_fileindex_alloc();
1923 	if (fileindex == NULL) {
1924 		err = got_error_from_errno("got_fileindex_alloc");
1925 		goto done;
1926 	}
1927 
1928 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
1929 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1930 		err = got_error_from_errno("asprintf");
1931 		fileindex_path = NULL;
1932 		goto done;
1933 	}
1934 
1935 	index = fopen(fileindex_path, "rb");
1936 	if (index == NULL) {
1937 		err = got_error_from_errno2("fopen", fileindex_path);
1938 		goto done;
1939 	}
1940 
1941 	err = got_fileindex_read(fileindex, index);
1942 	if (err)
1943 		goto done;
1944 
1945 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
1946 		struct got_fileindex_entry *ie = NULL;
1947 		char *relpath;
1948 
1949 		err = got_path_skip_common_ancestor(&relpath,
1950 		    got_worktree_get_root_path(worktree), pe->path);
1951 		if (err)
1952 			goto done;
1953 
1954 		/* Re-adding an existing entry is a no-op. */
1955 		if (got_fileindex_entry_get(fileindex, relpath) != NULL)
1956 			continue;
1957 
1958 		err = got_fileindex_entry_alloc(&ie, pe->path, relpath,
1959 		    NULL, NULL);
1960 		free(relpath);
1961 		if (err)
1962 			goto done;
1963 
1964 		err = got_fileindex_entry_add(fileindex, ie);
1965 		if (err) {
1966 			got_fileindex_entry_free(ie);
1967 			goto done;
1968 		}
1969 
1970 		err = report_file_status(ie, pe->path, status_cb, status_arg,
1971 		    repo);
1972 		if (err)
1973 			goto done;
1974 	}
1975 
1976 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1977 	    fileindex_path);
1978 	if (err)
1979 		goto done;
1980 
1981 	err = got_fileindex_write(fileindex, new_index);
1982 	if (err)
1983 		goto done;
1984 
1985 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1986 		err = got_error_from_errno3("rename", new_fileindex_path,
1987 		    fileindex_path);
1988 		goto done;
1989 	}
1990 
1991 	free(new_fileindex_path);
1992 	new_fileindex_path = NULL;
1993 
1994 done:
1995 	if (index) {
1996 		if (fclose(index) != 0 && err == NULL)
1997 			err = got_error_from_errno("fclose");
1998 	}
1999 	if (new_fileindex_path) {
2000 		if (unlink(new_fileindex_path) != 0 && err == NULL)
2001 			err = got_error_from_errno2("unlink",
2002 			    new_fileindex_path);
2003 		free(new_fileindex_path);
2004 	}
2005 	if (fileindex)
2006 		got_fileindex_free(fileindex);
2007 	unlockerr = lock_worktree(worktree, LOCK_SH);
2008 	if (unlockerr && err == NULL)
2009 		err = unlockerr;
2010 	return err;
2011 }
2012 
2013 const struct got_error *
2014 got_worktree_schedule_delete(struct got_worktree *worktree,
2015     const char *ondisk_path, int delete_local_mods,
2016     got_worktree_status_cb status_cb, void *status_arg,
2017     struct got_repository *repo)
2018 {
2019 	struct got_fileindex *fileindex = NULL;
2020 	struct got_fileindex_entry *ie = NULL;
2021 	char *relpath, *fileindex_path = NULL, *new_fileindex_path = NULL;
2022 	FILE *index = NULL, *new_index = NULL;
2023 	const struct got_error *err = NULL, *unlockerr = NULL;
2024 	unsigned char status;
2025 	struct stat sb;
2026 
2027 	err = lock_worktree(worktree, LOCK_EX);
2028 	if (err)
2029 		return err;
2030 
2031 	err = got_path_skip_common_ancestor(&relpath,
2032 	    got_worktree_get_root_path(worktree), ondisk_path);
2033 	if (err)
2034 		goto done;
2035 
2036 	fileindex = got_fileindex_alloc();
2037 	if (fileindex == NULL) {
2038 		err = got_error_from_errno("got_fileindex_alloc");
2039 		goto done;
2040 	}
2041 
2042 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2043 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2044 		err = got_error_from_errno("asprintf");
2045 		fileindex_path = NULL;
2046 		goto done;
2047 	}
2048 
2049 	index = fopen(fileindex_path, "rb");
2050 	if (index == NULL) {
2051 		err = got_error_from_errno2("fopen", fileindex_path);
2052 		goto done;
2053 	}
2054 
2055 	err = got_fileindex_read(fileindex, index);
2056 	if (err)
2057 		goto done;
2058 
2059 	ie = got_fileindex_entry_get(fileindex, relpath);
2060 	if (ie == NULL) {
2061 		err = got_error(GOT_ERR_BAD_PATH);
2062 		goto done;
2063 	}
2064 
2065 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2066 	if (err)
2067 		goto done;
2068 
2069 	if (status != GOT_STATUS_NO_CHANGE) {
2070 		if (status == GOT_STATUS_DELETE) {
2071 			err = got_error_set_errno(ENOENT, ondisk_path);
2072 			goto done;
2073 		}
2074 		if (status != GOT_STATUS_MODIFY) {
2075 			err = got_error(GOT_ERR_FILE_STATUS);
2076 			goto done;
2077 		}
2078 		if (!delete_local_mods) {
2079 			err = got_error(GOT_ERR_FILE_MODIFIED);
2080 			goto done;
2081 		}
2082 	}
2083 
2084 	if (unlink(ondisk_path) != 0) {
2085 		err = got_error_from_errno2("unlink", ondisk_path);
2086 		goto done;
2087 	}
2088 
2089 	got_fileindex_entry_mark_deleted_from_disk(ie);
2090 
2091 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2092 	    fileindex_path);
2093 	if (err)
2094 		goto done;
2095 
2096 	err = got_fileindex_write(fileindex, new_index);
2097 	if (err)
2098 		goto done;
2099 
2100 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2101 		err = got_error_from_errno3("rename", new_fileindex_path,
2102 		    fileindex_path);
2103 		goto done;
2104 	}
2105 
2106 	free(new_fileindex_path);
2107 	new_fileindex_path = NULL;
2108 
2109 	err = report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2110 done:
2111 	free(relpath);
2112 	if (index) {
2113 		if (fclose(index) != 0 && err == NULL)
2114 			err = got_error_from_errno("fclose");
2115 	}
2116 	if (new_fileindex_path) {
2117 		if (unlink(new_fileindex_path) != 0 && err == NULL)
2118 			err = got_error_from_errno2("unlink",
2119 			    new_fileindex_path);
2120 		free(new_fileindex_path);
2121 	}
2122 	if (fileindex)
2123 		got_fileindex_free(fileindex);
2124 	unlockerr = lock_worktree(worktree, LOCK_SH);
2125 	if (unlockerr && err == NULL)
2126 		err = unlockerr;
2127 	return err;
2128 }
2129 
2130 const struct got_error *
2131 got_worktree_revert(struct got_worktree *worktree,
2132     const char *ondisk_path,
2133     got_worktree_checkout_cb progress_cb, void *progress_arg,
2134     struct got_repository *repo)
2135 {
2136 	struct got_fileindex *fileindex = NULL;
2137 	struct got_fileindex_entry *ie = NULL;
2138 	char *relpath, *fileindex_path = NULL, *new_fileindex_path = NULL;
2139 	char *tree_path = NULL, *parent_path, *te_name;
2140 	FILE *index = NULL, *new_index = NULL;
2141 	const struct got_error *err = NULL, *unlockerr = NULL;
2142 	struct got_tree_object *tree = NULL;
2143 	struct got_object_id id, *tree_id = NULL;
2144 	const struct got_tree_entry *te;
2145 	struct got_blob_object *blob = NULL;
2146 	unsigned char status;
2147 	struct stat sb;
2148 
2149 	err = lock_worktree(worktree, LOCK_EX);
2150 	if (err)
2151 		return err;
2152 
2153 	err = got_path_skip_common_ancestor(&relpath,
2154 	    got_worktree_get_root_path(worktree), ondisk_path);
2155 	if (err)
2156 		goto done;
2157 
2158 	fileindex = got_fileindex_alloc();
2159 	if (fileindex == NULL) {
2160 		err = got_error_from_errno("got_fileindex_alloc");
2161 		goto done;
2162 	}
2163 
2164 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
2165 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2166 		err = got_error_from_errno("asprintf");
2167 		fileindex_path = NULL;
2168 		goto done;
2169 	}
2170 
2171 	index = fopen(fileindex_path, "rb");
2172 	if (index == NULL) {
2173 		err = got_error_from_errno2("fopen", fileindex_path);
2174 		goto done;
2175 	}
2176 
2177 	err = got_fileindex_read(fileindex, index);
2178 	if (err)
2179 		goto done;
2180 
2181 	ie = got_fileindex_entry_get(fileindex, relpath);
2182 	if (ie == NULL) {
2183 		err = got_error(GOT_ERR_BAD_PATH);
2184 		goto done;
2185 	}
2186 
2187 	/* Construct in-repository path of tree which contains this blob. */
2188 	err = got_path_dirname(&parent_path, ie->path);
2189 	if (err) {
2190 		if (err->code != GOT_ERR_BAD_PATH)
2191 			goto done;
2192 		parent_path = "/";
2193 	}
2194 	if (got_path_is_root_dir(worktree->path_prefix)) {
2195 		tree_path = strdup(parent_path);
2196 		if (tree_path == NULL) {
2197 			err = got_error_from_errno("strdup");
2198 			goto done;
2199 		}
2200 	} else {
2201 		if (got_path_is_root_dir(parent_path)) {
2202 			tree_path = strdup(worktree->path_prefix);
2203 			if (tree_path == NULL) {
2204 				err = got_error_from_errno("strdup");
2205 				goto done;
2206 			}
2207 		} else {
2208 			if (asprintf(&tree_path, "%s/%s",
2209 			    worktree->path_prefix, parent_path) == -1) {
2210 				err = got_error_from_errno("asprintf");
2211 				goto done;
2212 			}
2213 		}
2214 	}
2215 
2216 	err = got_object_id_by_path(&tree_id, repo, worktree->base_commit_id,
2217 	    tree_path);
2218 	if (err)
2219 		goto done;
2220 
2221 	err = got_object_open_as_tree(&tree, repo, tree_id);
2222 	if (err)
2223 		goto done;
2224 
2225 	te_name = basename(ie->path);
2226 	if (te_name == NULL) {
2227 		err = got_error_from_errno2("basename", ie->path);
2228 		goto done;
2229 	}
2230 
2231 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2232 	if (err)
2233 		goto done;
2234 
2235 	te = got_object_tree_find_entry(tree, te_name);
2236 	if (te == NULL && status != GOT_STATUS_ADD) {
2237 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
2238 		goto done;
2239 	}
2240 
2241 	switch (status) {
2242 	case GOT_STATUS_ADD:
2243 		(*progress_cb)(progress_arg, GOT_STATUS_REVERT, ie->path);
2244 		got_fileindex_entry_remove(fileindex, ie);
2245 		break;
2246 	case GOT_STATUS_DELETE:
2247 	case GOT_STATUS_MODIFY:
2248 	case GOT_STATUS_CONFLICT:
2249 	case GOT_STATUS_MISSING:
2250 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2251 		err = got_object_open_as_blob(&blob, repo, &id, 8192);
2252 		if (err)
2253 			goto done;
2254 		err = install_blob(worktree, ondisk_path, ie->path,
2255 		    te->mode, sb.st_mode, blob, 0, 1, repo, progress_cb,
2256 		    progress_arg);
2257 		if (err)
2258 			goto done;
2259 		if (status == GOT_STATUS_DELETE) {
2260 			err = update_blob_fileindex_entry(worktree,
2261 			    fileindex, ie, ondisk_path, ie->path, blob, 1);
2262 			if (err)
2263 				goto done;
2264 		}
2265 		break;
2266 	default:
2267 			goto done;
2268 	}
2269 
2270 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2271 	    fileindex_path);
2272 	if (err)
2273 		goto done;
2274 
2275 	err = got_fileindex_write(fileindex, new_index);
2276 	if (err)
2277 		goto done;
2278 
2279 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2280 		err = got_error_from_errno3("rename", new_fileindex_path,
2281 		    fileindex_path);
2282 		goto done;
2283 	}
2284 
2285 	free(new_fileindex_path);
2286 	new_fileindex_path = NULL;
2287 done:
2288 	free(relpath);
2289 	free(tree_path);
2290 	if (blob)
2291 		got_object_blob_close(blob);
2292 	if (tree)
2293 		got_object_tree_close(tree);
2294 	free(tree_id);
2295 	if (index) {
2296 		if (fclose(index) != 0 && err == NULL)
2297 			err = got_error_from_errno("fclose");
2298 	}
2299 	if (new_fileindex_path) {
2300 		if (unlink(new_fileindex_path) != 0 && err == NULL)
2301 			err = got_error_from_errno2("unlink",
2302 			    new_fileindex_path);
2303 		free(new_fileindex_path);
2304 	}
2305 	if (fileindex)
2306 		got_fileindex_free(fileindex);
2307 	unlockerr = lock_worktree(worktree, LOCK_SH);
2308 	if (unlockerr && err == NULL)
2309 		err = unlockerr;
2310 	return err;
2311 }
2312 
2313 static void
2314 free_commitable(struct got_commitable *ct)
2315 {
2316 	free(ct->path);
2317 	free(ct->in_repo_path);
2318 	free(ct->ondisk_path);
2319 	free(ct->blob_id);
2320 	free(ct->base_blob_id);
2321 	free(ct->base_commit_id);
2322 	free(ct);
2323 }
2324 
2325 struct collect_commitables_arg {
2326 	struct got_pathlist_head *commitable_paths;
2327 	struct got_repository *repo;
2328 	struct got_worktree *worktree;
2329 };
2330 
2331 static const struct got_error *
2332 collect_commitables(void *arg, unsigned char status, const char *relpath,
2333     struct got_object_id *blob_id, struct got_object_id *commit_id)
2334 {
2335 	struct collect_commitables_arg *a = arg;
2336 	const struct got_error *err = NULL;
2337 	struct got_commitable *ct = NULL;
2338 	struct got_pathlist_entry *new = NULL;
2339 	char *parent_path = NULL, *path = NULL;
2340 	struct stat sb;
2341 
2342 	if (status == GOT_STATUS_CONFLICT)
2343 		return got_error(GOT_ERR_COMMIT_CONFLICT);
2344 
2345 	if (status != GOT_STATUS_MODIFY && status != GOT_STATUS_ADD &&
2346 	    status != GOT_STATUS_DELETE)
2347 		return NULL;
2348 
2349 	if (asprintf(&path, "/%s", relpath) == -1) {
2350 		err = got_error_from_errno("asprintf");
2351 		goto done;
2352 	}
2353 	if (strcmp(path, "/") == 0) {
2354 		parent_path = strdup("");
2355 		if (parent_path == NULL)
2356 			return got_error_from_errno("strdup");
2357 	} else {
2358 		err = got_path_dirname(&parent_path, path);
2359 		if (err)
2360 			return err;
2361 	}
2362 
2363 	ct = calloc(1, sizeof(*ct));
2364 	if (ct == NULL) {
2365 		err = got_error_from_errno("calloc");
2366 		goto done;
2367 	}
2368 
2369 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
2370 	    relpath) == -1) {
2371 		err = got_error_from_errno("asprintf");
2372 		goto done;
2373 	}
2374 	if (status == GOT_STATUS_DELETE) {
2375 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
2376 	} else {
2377 		if (lstat(ct->ondisk_path, &sb) != 0) {
2378 			err = got_error_from_errno2("lstat", ct->ondisk_path);
2379 			goto done;
2380 		}
2381 		ct->mode = sb.st_mode;
2382 	}
2383 
2384 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
2385 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
2386 	    relpath) == -1) {
2387 		err = got_error_from_errno("asprintf");
2388 		goto done;
2389 	}
2390 
2391 	ct->status = status;
2392 	ct->blob_id = NULL; /* will be filled in when blob gets created */
2393 	if (ct->status != GOT_STATUS_ADD) {
2394 		ct->base_blob_id = got_object_id_dup(blob_id);
2395 		if (ct->base_blob_id == NULL) {
2396 			err = got_error_from_errno("got_object_id_dup");
2397 			goto done;
2398 		}
2399 		ct->base_commit_id = got_object_id_dup(commit_id);
2400 		if (ct->base_commit_id == NULL) {
2401 			err = got_error_from_errno("got_object_id_dup");
2402 			goto done;
2403 		}
2404 	}
2405 	ct->path = strdup(path);
2406 	if (ct->path == NULL) {
2407 		err = got_error_from_errno("strdup");
2408 		goto done;
2409 	}
2410 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
2411 done:
2412 	if (ct && (err || new == NULL))
2413 		free_commitable(ct);
2414 	free(parent_path);
2415 	free(path);
2416 	return err;
2417 }
2418 
2419 static const struct got_error *write_tree(struct got_object_id **,
2420     struct got_tree_object *, const char *, struct got_pathlist_head *,
2421     got_worktree_status_cb status_cb, void *status_arg,
2422     struct got_repository *);
2423 
2424 static const struct got_error *
2425 write_subtree(struct got_object_id **new_subtree_id,
2426     struct got_tree_entry *te, const char *parent_path,
2427     struct got_pathlist_head *commitable_paths,
2428     got_worktree_status_cb status_cb, void *status_arg,
2429     struct got_repository *repo)
2430 {
2431 	const struct got_error *err = NULL;
2432 	struct got_tree_object *subtree;
2433 	char *subpath;
2434 
2435 	if (asprintf(&subpath, "%s%s%s", parent_path,
2436 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
2437 		return got_error_from_errno("asprintf");
2438 
2439 	err = got_object_open_as_tree(&subtree, repo, te->id);
2440 	if (err)
2441 		return err;
2442 
2443 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
2444 	    status_cb, status_arg, repo);
2445 	got_object_tree_close(subtree);
2446 	free(subpath);
2447 	return err;
2448 }
2449 
2450 static const struct got_error *
2451 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
2452 {
2453 	const struct got_error *err = NULL;
2454 	char *ct_parent_path = NULL;
2455 
2456 	*match = 0;
2457 
2458 	if (strchr(ct->path, '/') == NULL) {
2459 		*match = got_path_is_root_dir(path);
2460 		return NULL;
2461 	}
2462 
2463 	err = got_path_dirname(&ct_parent_path, ct->path);
2464 	if (err)
2465 		return err;
2466 	*match = (strcmp(path, ct_parent_path) == 0);
2467 	free(ct_parent_path);
2468 	return err;
2469 }
2470 
2471 static mode_t
2472 get_ct_file_mode(struct got_commitable *ct)
2473 {
2474 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
2475 }
2476 
2477 static const struct got_error *
2478 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
2479     struct got_tree_entry *te, struct got_commitable *ct)
2480 {
2481 	const struct got_error *err = NULL;
2482 
2483 	*new_te = NULL;
2484 
2485 	err = got_object_tree_entry_dup(new_te, te);
2486 	if (err)
2487 		goto done;
2488 
2489 	(*new_te)->mode = get_ct_file_mode(ct);
2490 
2491 	free((*new_te)->id);
2492 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2493 	if ((*new_te)->id == NULL) {
2494 		err = got_error_from_errno("got_object_id_dup");
2495 		goto done;
2496 	}
2497 done:
2498 	if (err && *new_te) {
2499 		got_object_tree_entry_close(*new_te);
2500 		*new_te = NULL;
2501 	}
2502 	return err;
2503 }
2504 
2505 static const struct got_error *
2506 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
2507     struct got_commitable *ct)
2508 {
2509 	const struct got_error *err = NULL;
2510 	char *ct_name;
2511 
2512 	 *new_te = NULL;
2513 
2514 	*new_te = calloc(1, sizeof(**new_te));
2515 	if (*new_te == NULL)
2516 		return got_error_from_errno("calloc");
2517 
2518 	ct_name = basename(ct->path);
2519 	if (ct_name == NULL) {
2520 		err = got_error_from_errno2("basename", ct->path);
2521 		goto done;
2522 	}
2523 	(*new_te)->name = strdup(ct_name);
2524 	if ((*new_te)->name == NULL) {
2525 		err = got_error_from_errno("strdup");
2526 		goto done;
2527 	}
2528 
2529 	(*new_te)->mode = get_ct_file_mode(ct);
2530 
2531 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2532 	if ((*new_te)->id == NULL) {
2533 		err = got_error_from_errno("got_object_id_dup");
2534 		goto done;
2535 	}
2536 done:
2537 	if (err && *new_te) {
2538 		got_object_tree_entry_close(*new_te);
2539 		*new_te = NULL;
2540 	}
2541 	return err;
2542 }
2543 
2544 static const struct got_error *
2545 insert_tree_entry(struct got_tree_entry *new_te,
2546     struct got_pathlist_head *paths)
2547 {
2548 	const struct got_error *err = NULL;
2549 	struct got_pathlist_entry *new_pe;
2550 
2551 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
2552 	if (err)
2553 		return err;
2554 	if (new_pe == NULL)
2555 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
2556 	return NULL;
2557 }
2558 
2559 static const struct got_error *
2560 report_ct_status(struct got_commitable *ct,
2561     got_worktree_status_cb status_cb, void *status_arg)
2562 {
2563 	const char *ct_path = ct->path;
2564 	while (ct_path[0] == '/')
2565 		ct_path++;
2566 	return (*status_cb)(status_arg, ct->status, ct_path, ct->blob_id, NULL);
2567 }
2568 
2569 static const struct got_error *
2570 match_modified_subtree(int *modified, struct got_tree_entry *te,
2571     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
2572 {
2573 	const struct got_error *err = NULL;
2574 	struct got_pathlist_entry *pe;
2575 	char *te_path;
2576 
2577 	*modified = 0;
2578 
2579 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
2580 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
2581 	    te->name) == -1)
2582 		return got_error_from_errno("asprintf");
2583 
2584 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2585 		struct got_commitable *ct = pe->data;
2586 		*modified = got_path_is_child(ct->in_repo_path, te_path,
2587 		    strlen(te_path));
2588 		 if (*modified)
2589 			break;
2590 	}
2591 
2592 	free(te_path);
2593 	return err;
2594 }
2595 
2596 static const struct got_error *
2597 match_deleted_or_modified_ct(struct got_commitable **ctp,
2598     struct got_tree_entry *te, const char *base_tree_path,
2599     struct got_pathlist_head *commitable_paths)
2600 {
2601 	const struct got_error *err = NULL;
2602 	struct got_pathlist_entry *pe;
2603 
2604 	*ctp = NULL;
2605 
2606 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2607 		struct got_commitable *ct = pe->data;
2608 		char *ct_name = NULL;
2609 		int path_matches;
2610 
2611 		if (ct->status != GOT_STATUS_MODIFY &&
2612 		    ct->status != GOT_STATUS_DELETE)
2613 			continue;
2614 
2615 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
2616 			continue;
2617 
2618 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
2619 		 if (err)
2620 			return err;
2621 		if (!path_matches)
2622 			continue;
2623 
2624 		ct_name = basename(pe->path);
2625 		if (ct_name == NULL)
2626 			return got_error_from_errno2("basename", pe->path);
2627 
2628 		if (strcmp(te->name, ct_name) != 0)
2629 			continue;
2630 
2631 		*ctp = ct;
2632 		break;
2633 	}
2634 
2635 	return err;
2636 }
2637 
2638 static const struct got_error *
2639 write_tree(struct got_object_id **new_tree_id,
2640     struct got_tree_object *base_tree, const char *path_base_tree,
2641     struct got_pathlist_head *commitable_paths,
2642     got_worktree_status_cb status_cb, void *status_arg,
2643     struct got_repository *repo)
2644 {
2645 	const struct got_error *err = NULL;
2646 	const struct got_tree_entries *base_entries = NULL;
2647 	struct got_pathlist_head paths;
2648 	struct got_tree_entries new_tree_entries;
2649 	struct got_tree_entry *te, *new_te = NULL;
2650 	struct got_pathlist_entry *pe;
2651 
2652 	TAILQ_INIT(&paths);
2653 	new_tree_entries.nentries = 0;
2654 	SIMPLEQ_INIT(&new_tree_entries.head);
2655 
2656 	/* Insert, and recurse into, newly added entries first. */
2657 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2658 		struct got_commitable *ct = pe->data;
2659 		char *child_path = NULL, *slash;
2660 
2661 		if (ct->status != GOT_STATUS_ADD ||
2662 		    (ct->flags & GOT_COMMITABLE_ADDED))
2663 			continue;
2664 
2665 		 if (!got_path_is_child(pe->path, path_base_tree,
2666 		     strlen(path_base_tree)))
2667 			continue;
2668 
2669 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
2670 		    pe->path);
2671 		if (err)
2672 			goto done;
2673 
2674 		slash = strchr(child_path, '/');
2675 		if (slash == NULL) {
2676 			err = alloc_added_blob_tree_entry(&new_te, ct);
2677 			if (err)
2678 				goto done;
2679 			err = report_ct_status(ct, status_cb, status_arg);
2680 			if (err)
2681 				goto done;
2682 			ct->flags |= GOT_COMMITABLE_ADDED;
2683 		} else {
2684 			char *subtree_path;
2685 
2686 			*slash = '\0'; /* trim trailing path components */
2687 			if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
2688 			    got_path_is_root_dir(path_base_tree) ? "" : "/",
2689 			    child_path) == -1) {
2690 				err = got_error_from_errno("asprintf");
2691 				goto done;
2692 			}
2693 
2694 			new_te = calloc(1, sizeof(*new_te));
2695 			new_te->mode = S_IFDIR;
2696 			new_te->name = strdup(child_path);
2697 			if (new_te->name == NULL) {
2698 				err = got_error_from_errno("strdup");
2699 				got_object_tree_entry_close(new_te);
2700 				new_te = NULL;
2701 				goto done;
2702 			}
2703 			err = write_tree(&new_te->id, NULL, subtree_path,
2704 			    commitable_paths, status_cb, status_arg, repo);
2705 			free(subtree_path);
2706 			if (err) {
2707 				got_object_tree_entry_close(new_te);
2708 				new_te = NULL;
2709 				goto done;
2710 			}
2711 		}
2712 		err = insert_tree_entry(new_te, &paths);
2713 		if (err)
2714 			goto done;
2715 	}
2716 
2717 	if (base_tree) {
2718 		/* Handle modified and deleted entries. */
2719 		base_entries = got_object_tree_get_entries(base_tree);
2720 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
2721 			struct got_commitable *ct = NULL;
2722 
2723 			if (S_ISDIR(te->mode)) {
2724 				int modified;
2725 				err = got_object_tree_entry_dup(&new_te, te);
2726 				if (err)
2727 					goto done;
2728 				err = match_modified_subtree(&modified, te,
2729 				    path_base_tree, commitable_paths);
2730 				if (err)
2731 					goto done;
2732 				/* Avoid recursion into unmodified subtrees. */
2733 				if (modified) {
2734 					free(new_te->id);
2735 					err = write_subtree(&new_te->id, te,
2736 					    path_base_tree, commitable_paths,
2737 					    status_cb, status_arg, repo);
2738 					if (err)
2739 						goto done;
2740 				}
2741 				err = insert_tree_entry(new_te, &paths);
2742 				if (err)
2743 					goto done;
2744 				continue;
2745 			}
2746 
2747 			err = match_deleted_or_modified_ct(&ct, te,
2748 			    path_base_tree, commitable_paths);
2749 			if (ct) {
2750 				/* NB: Deleted entries get dropped here. */
2751 				if (ct->status == GOT_STATUS_MODIFY) {
2752 					err = alloc_modified_blob_tree_entry(
2753 					    &new_te, te, ct);
2754 					if (err)
2755 						goto done;
2756 					err = insert_tree_entry(new_te, &paths);
2757 					if (err)
2758 						goto done;
2759 				}
2760 				err = report_ct_status(ct, status_cb,
2761 				    status_arg);
2762 				if (err)
2763 					goto done;
2764 			} else {
2765 				/* Entry is unchanged; just copy it. */
2766 				err = got_object_tree_entry_dup(&new_te, te);
2767 				if (err)
2768 					goto done;
2769 				err = insert_tree_entry(new_te, &paths);
2770 				if (err)
2771 					goto done;
2772 			}
2773 		}
2774 	}
2775 
2776 	/* Write new list of entries; deleted entries have been dropped. */
2777 	TAILQ_FOREACH(pe, &paths, entry) {
2778 		struct got_tree_entry *te = pe->data;
2779 		new_tree_entries.nentries++;
2780 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
2781 	}
2782 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
2783 done:
2784 	got_object_tree_entries_close(&new_tree_entries);
2785 	got_pathlist_free(&paths);
2786 	return err;
2787 }
2788 
2789 static const struct got_error *
2790 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
2791     struct got_object_id *new_base_commit_id, struct got_worktree *worktree)
2792 {
2793 	const struct got_error *err = NULL;
2794 	char *fileindex_path = NULL, *new_fileindex_path = NULL;
2795 	struct got_fileindex *fileindex = NULL;
2796 	FILE *new_index = NULL;
2797 	struct got_pathlist_entry *pe;
2798 
2799 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2800 	if (err)
2801 		return err;
2802 
2803 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2804 	    fileindex_path);
2805 	if (err)
2806 		goto done;
2807 
2808 	TAILQ_FOREACH(pe, commitable_paths, entry) {
2809 		struct got_fileindex_entry *ie;
2810 		struct got_commitable *ct = pe->data;
2811 
2812 		ie = got_fileindex_entry_get(fileindex, pe->path);
2813 		if (ie) {
2814 			if (ct->status == GOT_STATUS_DELETE) {
2815 				got_fileindex_entry_remove(fileindex, ie);
2816 				got_fileindex_entry_free(ie);
2817 			} else
2818 				err = got_fileindex_entry_update(ie,
2819 				    ct->ondisk_path, ct->blob_id->sha1,
2820 				    new_base_commit_id->sha1, 1);
2821 		} else {
2822 			err = got_fileindex_entry_alloc(&ie,
2823 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
2824 			    new_base_commit_id->sha1);
2825 			if (err)
2826 				goto done;
2827 			err = got_fileindex_entry_add(fileindex, ie);
2828 			if (err)
2829 				goto done;
2830 		}
2831 	}
2832 
2833 	err = got_fileindex_write(fileindex, new_index);
2834 	if (err)
2835 		goto done;
2836 
2837 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2838 		err = got_error_from_errno3("rename", new_fileindex_path,
2839 		    fileindex_path);
2840 		unlink(new_fileindex_path);
2841 		goto done;
2842 	}
2843 
2844 	free(new_fileindex_path);
2845 	new_fileindex_path = NULL;
2846 
2847 done:
2848 	if (new_fileindex_path)
2849 		unlink(new_fileindex_path);
2850 	if (new_index)
2851 		fclose(new_index);
2852 	free(new_fileindex_path);
2853 	free(fileindex_path);
2854 	got_fileindex_free(fileindex);
2855 	return err;
2856 }
2857 
2858 static const struct got_error *
2859 check_ct_out_of_date(struct got_commitable *ct, struct got_repository *repo,
2860 	struct got_object_id *head_commit_id)
2861 {
2862 	const struct got_error *err = NULL;
2863 	struct got_object_id *id_in_head;
2864 
2865 	/*
2866 	 * Require that modified/deleted files are based on the branch head.
2867 	 * This requirement could be relaxed to force less update operations
2868 	 * on users but, for now, we want to play it safe and see how it goes.
2869 	 *
2870 	 * If this check is relaxed, it must still ensure that no modifications
2871 	 * were made to files *and their parents* in commits between the file's
2872 	 * base commit and the branch head. Otherwise, tree conflicts will not
2873 	 * be detected reliably.
2874 	 */
2875 	if (ct->status != GOT_STATUS_ADD) {
2876 		if (got_object_id_cmp(ct->base_commit_id, head_commit_id) != 0)
2877 			return got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
2878 		return NULL;
2879 	}
2880 
2881 	/* Require that added files don't exist in the branch head. */
2882 	err = got_object_id_by_path(&id_in_head, repo, head_commit_id,
2883 	    ct->in_repo_path);
2884 	if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
2885 		return err;
2886 	if (id_in_head) {
2887 		free(id_in_head);
2888 		return got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
2889 	}
2890 
2891 	free(id_in_head);
2892 	return NULL;
2893 }
2894 
2895 const struct got_error *
2896 got_worktree_commit(struct got_object_id **new_commit_id,
2897     struct got_worktree *worktree, const char *ondisk_path,
2898     const char *author, const char *committer,
2899     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
2900     got_worktree_status_cb status_cb, void *status_arg,
2901     struct got_repository *repo)
2902 {
2903 	const struct got_error *err = NULL, *unlockerr = NULL;
2904 	struct collect_commitables_arg cc_arg;
2905 	struct got_pathlist_head commitable_paths;
2906 	struct got_pathlist_entry *pe;
2907 	char *relpath = NULL;
2908 	const char *head_ref_name = NULL;
2909 	struct got_reference *head_ref = NULL;
2910 	struct got_commit_object *head_commit = NULL;
2911 	struct got_object_id *head_commit_id = NULL;
2912 	struct got_reference *head_ref2 = NULL;
2913 	struct got_object_id *head_commit_id2 = NULL;
2914 	struct got_tree_object *head_tree = NULL;
2915 	struct got_object_id *new_tree_id = NULL;
2916 	struct got_object_id_queue parent_ids;
2917 	struct got_object_qid *pid = NULL;
2918 	char *logmsg = NULL;
2919 
2920 	*new_commit_id = NULL;
2921 
2922 	TAILQ_INIT(&commitable_paths);
2923 	SIMPLEQ_INIT(&parent_ids);
2924 
2925 	if (ondisk_path) {
2926 		err = got_path_skip_common_ancestor(&relpath,
2927 		    worktree->root_path, ondisk_path);
2928 		if (err)
2929 			return err;
2930 	}
2931 
2932 	err = lock_worktree(worktree, LOCK_EX);
2933 	if (err)
2934 		goto done;
2935 
2936 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
2937 	if (err)
2938 		goto done;
2939 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
2940 	if (err)
2941 		goto done;
2942 
2943 	cc_arg.commitable_paths = &commitable_paths;
2944 	cc_arg.worktree = worktree;
2945 	cc_arg.repo = repo;
2946 	err = got_worktree_status(worktree, relpath ? relpath : "",
2947 	    repo, collect_commitables, &cc_arg, NULL, NULL);
2948 	if (err)
2949 		goto done;
2950 
2951 	if (TAILQ_EMPTY(&commitable_paths)) {
2952 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
2953 		goto done;
2954 	}
2955 
2956 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
2957 	if (err)
2958 		goto done;
2959 
2960 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
2961 		struct got_commitable *ct = pe->data;
2962 		err = check_ct_out_of_date(ct, repo, head_commit_id);
2963 		if (err)
2964 			goto done;
2965 	}
2966 
2967 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
2968 	if (err)
2969 		goto done;
2970 
2971 	if (commit_msg_cb != NULL) {
2972 		err = commit_msg_cb(&commitable_paths, &logmsg, commit_arg);
2973 		if (err)
2974 			goto done;
2975 	}
2976 
2977 	if (logmsg == NULL || strlen(logmsg) == 0) {
2978 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
2979 		goto done;
2980 	}
2981 
2982 	/* Create blobs from added and modified files and record their IDs. */
2983 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
2984 		struct got_commitable *ct = pe->data;
2985 		char *ondisk_path;
2986 
2987 		if (ct->status != GOT_STATUS_ADD &&
2988 		    ct->status != GOT_STATUS_MODIFY)
2989 			continue;
2990 
2991 		if (asprintf(&ondisk_path, "%s/%s",
2992 		    worktree->root_path, pe->path) == -1) {
2993 			err = got_error_from_errno("asprintf");
2994 			goto done;
2995 		}
2996 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
2997 		free(ondisk_path);
2998 		if (err)
2999 			goto done;
3000 	}
3001 
3002 	/* Recursively write new tree objects. */
3003 	err = write_tree(&new_tree_id, head_tree, "/", &commitable_paths,
3004 	    status_cb, status_arg, repo);
3005 	if (err)
3006 		goto done;
3007 
3008 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
3009 	if (err)
3010 		goto done;
3011 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
3012 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
3013 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
3014 	got_object_qid_free(pid);
3015 	if (logmsg != NULL)
3016 		free(logmsg);
3017 	if (err)
3018 		goto done;
3019 
3020 	/* Check if a concurrent commit to our branch has occurred. */
3021 	head_ref_name = got_worktree_get_head_ref_name(worktree);
3022 	if (head_ref_name == NULL) {
3023 		err = got_error_from_errno("got_worktree_get_head_ref_name");
3024 		goto done;
3025 	}
3026 	/* Lock the reference here to prevent concurrent modification. */
3027 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
3028 	if (err)
3029 		goto done;
3030 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
3031 	if (err)
3032 		goto done;
3033 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
3034 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
3035 		goto done;
3036 	}
3037 	/* Update branch head in repository. */
3038 	err = got_ref_change_ref(head_ref2, *new_commit_id);
3039 	if (err)
3040 		goto done;
3041 	err = got_ref_write(head_ref2, repo);
3042 	if (err)
3043 		goto done;
3044 
3045 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
3046 	if (err)
3047 		goto done;
3048 
3049 	err = ref_base_commit(worktree, repo);
3050 	if (err)
3051 		goto done;
3052 
3053 	err = update_fileindex_after_commit(&commitable_paths,
3054 	    *new_commit_id, worktree);
3055 	if (err)
3056 		goto done;
3057 done:
3058 	unlockerr = lock_worktree(worktree, LOCK_SH);
3059 	if (unlockerr && err == NULL)
3060 		err = unlockerr;
3061 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3062 		struct got_commitable *ct = pe->data;
3063 		free_commitable(ct);
3064 	}
3065 	got_pathlist_free(&commitable_paths);
3066 	if (head_tree)
3067 		got_object_tree_close(head_tree);
3068 	if (head_commit)
3069 		got_object_commit_close(head_commit);
3070 	free(relpath);
3071 	free(head_commit_id);
3072 	free(head_commit_id2);
3073 	if (head_ref)
3074 		got_ref_close(head_ref);
3075 	if (head_ref2) {
3076 		unlockerr = got_ref_unlock(head_ref2);
3077 		if (unlockerr && err == NULL)
3078 			err = unlockerr;
3079 		got_ref_close(head_ref2);
3080 	}
3081 	return err;
3082 }
3083 
3084 const char *
3085 got_commitable_get_path(struct got_commitable *ct)
3086 {
3087 	return ct->path;
3088 }
3089 
3090 unsigned int
3091 got_commitable_get_status(struct got_commitable *ct)
3092 {
3093 	return ct->status;
3094 }