1 /*
2  * Copyright (c) 2018, 2019 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/stat.h>
18 #include <sys/limits.h>
19 #include <sys/queue.h>
20 #include <sys/tree.h>
21 
22 #include <dirent.h>
23 #include <stddef.h>
24 #include <string.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <fcntl.h>
28 #include <errno.h>
29 #include <unistd.h>
30 #include <sha1.h>
31 #include <zlib.h>
32 #include <fnmatch.h>
33 #include <libgen.h>
34 #include <uuid.h>
35 #include <util.h>
36 
37 #include "got_error.h"
38 #include "got_repository.h"
39 #include "got_reference.h"
40 #include "got_object.h"
41 #include "got_path.h"
42 #include "got_worktree.h"
43 #include "got_opentemp.h"
44 #include "got_diff.h"
45 
46 #include "got_lib_worktree.h"
47 #include "got_lib_sha1.h"
48 #include "got_lib_fileindex.h"
49 #include "got_lib_inflate.h"
50 #include "got_lib_delta.h"
51 #include "got_lib_object.h"
52 #include "got_lib_object_parse.h"
53 #include "got_lib_object_create.h"
54 #include "got_lib_object_idset.h"
55 #include "got_lib_diff.h"
56 
57 #ifndef MIN
58 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
59 #endif
60 
61 static const struct got_error *
62 create_meta_file(const char *path_got, const char *name, const char *content)
63 {
64 	const struct got_error *err = NULL;
65 	char *path;
66 
67 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
68 		return got_error_from_errno("asprintf");
69 
70 	err = got_path_create_file(path, content);
71 	free(path);
72 	return err;
73 }
74 
75 static const struct got_error *
76 update_meta_file(const char *path_got, const char *name, const char *content)
77 {
78 	const struct got_error *err = NULL;
79 	FILE *tmpfile = NULL;
80 	char *tmppath = NULL;
81 	char *path = NULL;
82 
83 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
84 		err = got_error_from_errno("asprintf");
85 		path = NULL;
86 		goto done;
87 	}
88 
89 	err = got_opentemp_named(&tmppath, &tmpfile, path);
90 	if (err)
91 		goto done;
92 
93 	if (content) {
94 		int len = fprintf(tmpfile, "%s\n", content);
95 		if (len != strlen(content) + 1) {
96 			err = got_error_from_errno2("fprintf", tmppath);
97 			goto done;
98 		}
99 	}
100 
101 	if (rename(tmppath, path) != 0) {
102 		err = got_error_from_errno3("rename", tmppath, path);
103 		unlink(tmppath);
104 		goto done;
105 	}
106 
107 done:
108 	if (fclose(tmpfile) != 0 && err == NULL)
109 		err = got_error_from_errno2("fclose", tmppath);
110 	free(tmppath);
111 	return err;
112 }
113 
114 static const struct got_error *
115 read_meta_file(char **content, const char *path_got, const char *name)
116 {
117 	const struct got_error *err = NULL;
118 	char *path;
119 	int fd = -1;
120 	ssize_t n;
121 	struct stat sb;
122 
123 	*content = NULL;
124 
125 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
126 		err = got_error_from_errno("asprintf");
127 		path = NULL;
128 		goto done;
129 	}
130 
131 	fd = open(path, O_RDONLY | O_NOFOLLOW);
132 	if (fd == -1) {
133 		if (errno == ENOENT)
134 			err = got_error_path(path, GOT_ERR_WORKTREE_META);
135 		else
136 			err = got_error_from_errno2("open", path);
137 		goto done;
138 	}
139 	if (flock(fd, LOCK_SH | LOCK_NB) == -1) {
140 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
141 		    : got_error_from_errno2("flock", path));
142 		goto done;
143 	}
144 
145 	if (fstat(fd, &sb) != 0) {
146 		err = got_error_from_errno2("fstat", path);
147 		goto done;
148 	}
149 	*content = calloc(1, sb.st_size);
150 	if (*content == NULL) {
151 		err = got_error_from_errno("calloc");
152 		goto done;
153 	}
154 
155 	n = read(fd, *content, sb.st_size);
156 	if (n != sb.st_size) {
157 		err = (n == -1 ? got_error_from_errno2("read", path) :
158 		    got_error_path(path, GOT_ERR_WORKTREE_META));
159 		goto done;
160 	}
161 	if ((*content)[sb.st_size - 1] != '\n') {
162 		err = got_error_path(path, GOT_ERR_WORKTREE_META);
163 		goto done;
164 	}
165 	(*content)[sb.st_size - 1] = '\0';
166 
167 done:
168 	if (fd != -1 && close(fd) == -1 && err == NULL)
169 		err = got_error_from_errno2("close", path_got);
170 	free(path);
171 	if (err) {
172 		free(*content);
173 		*content = NULL;
174 	}
175 	return err;
176 }
177 
178 static const struct got_error *
179 write_head_ref(const char *path_got, struct got_reference *head_ref)
180 {
181 	const struct got_error *err = NULL;
182 	char *refstr = NULL;
183 
184 	if (got_ref_is_symbolic(head_ref)) {
185 		refstr = got_ref_to_str(head_ref);
186 		if (refstr == NULL)
187 			return got_error_from_errno("got_ref_to_str");
188 	} else {
189 		refstr = strdup(got_ref_get_name(head_ref));
190 		if (refstr == NULL)
191 			return got_error_from_errno("strdup");
192 	}
193 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
194 	free(refstr);
195 	return err;
196 }
197 
198 const struct got_error *
199 got_worktree_init(const char *path, struct got_reference *head_ref,
200     const char *prefix, struct got_repository *repo)
201 {
202 	const struct got_error *err = NULL;
203 	struct got_object_id *commit_id = NULL;
204 	uuid_t uuid;
205 	uint32_t uuid_status;
206 	int obj_type;
207 	char *path_got = NULL;
208 	char *formatstr = NULL;
209 	char *absprefix = NULL;
210 	char *basestr = NULL;
211 	char *uuidstr = NULL;
212 
213 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
214 		err = got_error(GOT_ERR_WORKTREE_REPO);
215 		goto done;
216 	}
217 
218 	err = got_ref_resolve(&commit_id, repo, head_ref);
219 	if (err)
220 		return err;
221 	err = got_object_get_type(&obj_type, repo, commit_id);
222 	if (err)
223 		return err;
224 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
225 		return got_error(GOT_ERR_OBJ_TYPE);
226 
227 	if (!got_path_is_absolute(prefix)) {
228 		if (asprintf(&absprefix, "/%s", prefix) == -1)
229 			return got_error_from_errno("asprintf");
230 	}
231 
232 	/* Create top-level directory (may already exist). */
233 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
234 		err = got_error_from_errno2("mkdir", path);
235 		goto done;
236 	}
237 
238 	/* Create .got directory (may already exist). */
239 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
240 		err = got_error_from_errno("asprintf");
241 		goto done;
242 	}
243 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
244 		err = got_error_from_errno2("mkdir", path_got);
245 		goto done;
246 	}
247 
248 	/* Create an empty lock file. */
249 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
250 	if (err)
251 		goto done;
252 
253 	/* Create an empty file index. */
254 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
255 	if (err)
256 		goto done;
257 
258 	/* Write the HEAD reference. */
259 	err = write_head_ref(path_got, head_ref);
260 	if (err)
261 		goto done;
262 
263 	/* Record our base commit. */
264 	err = got_object_id_str(&basestr, commit_id);
265 	if (err)
266 		goto done;
267 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
268 	if (err)
269 		goto done;
270 
271 	/* Store path to repository. */
272 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
273 	    got_repo_get_path(repo));
274 	if (err)
275 		goto done;
276 
277 	/* Store in-repository path prefix. */
278 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
279 	    absprefix ? absprefix : prefix);
280 	if (err)
281 		goto done;
282 
283 	/* Generate UUID. */
284 	uuid_create(&uuid, &uuid_status);
285 	if (uuid_status != uuid_s_ok) {
286 		err = got_error_uuid(uuid_status);
287 		goto done;
288 	}
289 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
290 	if (uuid_status != uuid_s_ok) {
291 		err = got_error_uuid(uuid_status);
292 		goto done;
293 	}
294 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
295 	if (err)
296 		goto done;
297 
298 	/* Stamp work tree with format file. */
299 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
300 		err = got_error_from_errno("asprintf");
301 		goto done;
302 	}
303 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
304 	if (err)
305 		goto done;
306 
307 done:
308 	free(commit_id);
309 	free(path_got);
310 	free(formatstr);
311 	free(absprefix);
312 	free(basestr);
313 	free(uuidstr);
314 	return err;
315 }
316 
317 static const struct got_error *
318 open_worktree(struct got_worktree **worktree, const char *path)
319 {
320 	const struct got_error *err = NULL;
321 	char *path_got;
322 	char *formatstr = NULL;
323 	char *uuidstr = NULL;
324 	char *path_lock = NULL;
325 	char *base_commit_id_str = NULL;
326 	int version, fd = -1;
327 	const char *errstr;
328 	struct got_repository *repo = NULL;
329 	uint32_t uuid_status;
330 
331 	*worktree = NULL;
332 
333 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
334 		err = got_error_from_errno("asprintf");
335 		path_got = NULL;
336 		goto done;
337 	}
338 
339 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
340 		err = got_error_from_errno("asprintf");
341 		path_lock = NULL;
342 		goto done;
343 	}
344 
345 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
346 	if (fd == -1) {
347 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
348 		    : got_error_from_errno2("open", path_lock));
349 		goto done;
350 	}
351 
352 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
353 	if (err)
354 		goto done;
355 
356 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
357 	if (errstr) {
358 		err = got_error_msg(GOT_ERR_WORKTREE_META,
359 		    "could not parse work tree format version number");
360 		goto done;
361 	}
362 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
363 		err = got_error(GOT_ERR_WORKTREE_VERS);
364 		goto done;
365 	}
366 
367 	*worktree = calloc(1, sizeof(**worktree));
368 	if (*worktree == NULL) {
369 		err = got_error_from_errno("calloc");
370 		goto done;
371 	}
372 	(*worktree)->lockfd = -1;
373 
374 	(*worktree)->root_path = strdup(path);
375 	if ((*worktree)->root_path == NULL) {
376 		err = got_error_from_errno("strdup");
377 		goto done;
378 	}
379 	err = read_meta_file(&(*worktree)->repo_path, path_got,
380 	    GOT_WORKTREE_REPOSITORY);
381 	if (err)
382 		goto done;
383 
384 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
385 	    GOT_WORKTREE_PATH_PREFIX);
386 	if (err)
387 		goto done;
388 
389 	err = read_meta_file(&base_commit_id_str, path_got,
390 	    GOT_WORKTREE_BASE_COMMIT);
391 	if (err)
392 		goto done;
393 
394 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
395 	if (err)
396 		goto done;
397 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
398 	if (uuid_status != uuid_s_ok) {
399 		err = got_error_uuid(uuid_status);
400 		goto done;
401 	}
402 
403 	err = got_repo_open(&repo, (*worktree)->repo_path);
404 	if (err)
405 		goto done;
406 
407 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
408 	    base_commit_id_str);
409 	if (err)
410 		goto done;
411 
412 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
413 	    GOT_WORKTREE_HEAD_REF);
414 done:
415 	if (repo)
416 		got_repo_close(repo);
417 	free(path_got);
418 	free(path_lock);
419 	free(base_commit_id_str);
420 	free(uuidstr);
421 	free(formatstr);
422 	if (err) {
423 		if (fd != -1)
424 			close(fd);
425 		if (*worktree != NULL)
426 			got_worktree_close(*worktree);
427 		*worktree = NULL;
428 	} else
429 		(*worktree)->lockfd = fd;
430 
431 	return err;
432 }
433 
434 const struct got_error *
435 got_worktree_open(struct got_worktree **worktree, const char *path)
436 {
437 	const struct got_error *err = NULL;
438 
439 	do {
440 		err = open_worktree(worktree, path);
441 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT))
442 			return err;
443 		if (*worktree)
444 			return NULL;
445 		path = dirname(path);
446 		if (path == NULL)
447 			return got_error_from_errno2("dirname", path);
448 	} while (!((path[0] == '.' || path[0] == '/') && path[1] == '\0'));
449 
450 	return got_error(GOT_ERR_NOT_WORKTREE);
451 }
452 
453 const struct got_error *
454 got_worktree_close(struct got_worktree *worktree)
455 {
456 	const struct got_error *err = NULL;
457 	free(worktree->root_path);
458 	free(worktree->repo_path);
459 	free(worktree->path_prefix);
460 	free(worktree->base_commit_id);
461 	free(worktree->head_ref_name);
462 	if (worktree->lockfd != -1)
463 		if (close(worktree->lockfd) != 0)
464 			err = got_error_from_errno2("close",
465 			    got_worktree_get_root_path(worktree));
466 	free(worktree);
467 	return err;
468 }
469 
470 const char *
471 got_worktree_get_root_path(struct got_worktree *worktree)
472 {
473 	return worktree->root_path;
474 }
475 
476 const char *
477 got_worktree_get_repo_path(struct got_worktree *worktree)
478 {
479 	return worktree->repo_path;
480 }
481 
482 const char *
483 got_worktree_get_path_prefix(struct got_worktree *worktree)
484 {
485 	return worktree->path_prefix;
486 }
487 
488 const struct got_error *
489 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
490     const char *path_prefix)
491 {
492 	char *absprefix = NULL;
493 
494 	if (!got_path_is_absolute(path_prefix)) {
495 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
496 			return got_error_from_errno("asprintf");
497 	}
498 	*match = (strcmp(absprefix ? absprefix : path_prefix,
499 	    worktree->path_prefix) == 0);
500 	free(absprefix);
501 	return NULL;
502 }
503 
504 const char *
505 got_worktree_get_head_ref_name(struct got_worktree *worktree)
506 {
507 	return worktree->head_ref_name;
508 }
509 
510 const struct got_error *
511 got_worktree_set_head_ref(struct got_worktree *worktree,
512     struct got_reference *head_ref)
513 {
514 	const struct got_error *err = NULL;
515 	char *path_got = NULL, *head_ref_name = NULL;
516 
517 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
518 	    GOT_WORKTREE_GOT_DIR) == -1) {
519 		err = got_error_from_errno("asprintf");
520 		path_got = NULL;
521 		goto done;
522 	}
523 
524 	head_ref_name = strdup(got_ref_get_name(head_ref));
525 	if (head_ref_name == NULL) {
526 		err = got_error_from_errno("strdup");
527 		goto done;
528 	}
529 
530 	err = write_head_ref(path_got, head_ref);
531 	if (err)
532 		goto done;
533 
534 	free(worktree->head_ref_name);
535 	worktree->head_ref_name = head_ref_name;
536 done:
537 	free(path_got);
538 	if (err)
539 		free(head_ref_name);
540 	return err;
541 }
542 
543 struct got_object_id *
544 got_worktree_get_base_commit_id(struct got_worktree *worktree)
545 {
546 	return worktree->base_commit_id;
547 }
548 
549 const struct got_error *
550 got_worktree_set_base_commit_id(struct got_worktree *worktree,
551     struct got_repository *repo, struct got_object_id *commit_id)
552 {
553 	const struct got_error *err;
554 	struct got_object *obj = NULL;
555 	char *id_str = NULL;
556 	char *path_got = NULL;
557 
558 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
559 	    GOT_WORKTREE_GOT_DIR) == -1) {
560 		err = got_error_from_errno("asprintf");
561 		path_got = NULL;
562 		goto done;
563 	}
564 
565 	err = got_object_open(&obj, repo, commit_id);
566 	if (err)
567 		return err;
568 
569 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
570 		err = got_error(GOT_ERR_OBJ_TYPE);
571 		goto done;
572 	}
573 
574 	/* Record our base commit. */
575 	err = got_object_id_str(&id_str, commit_id);
576 	if (err)
577 		goto done;
578 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
579 	if (err)
580 		goto done;
581 
582 	free(worktree->base_commit_id);
583 	worktree->base_commit_id = got_object_id_dup(commit_id);
584 	if (worktree->base_commit_id == NULL) {
585 		err = got_error_from_errno("got_object_id_dup");
586 		goto done;
587 	}
588 done:
589 	if (obj)
590 		got_object_close(obj);
591 	free(id_str);
592 	free(path_got);
593 	return err;
594 }
595 
596 static const struct got_error *
597 lock_worktree(struct got_worktree *worktree, int operation)
598 {
599 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
600 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
601 		    : got_error_from_errno2("flock",
602 		    got_worktree_get_root_path(worktree)));
603 	return NULL;
604 }
605 
606 static const struct got_error *
607 add_dir_on_disk(struct got_worktree *worktree, const char *path)
608 {
609 	const struct got_error *err = NULL;
610 	char *abspath;
611 
612 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
613 		return got_error_from_errno("asprintf");
614 
615 	err = got_path_mkdir(abspath);
616 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
617 		struct stat sb;
618 		err = NULL;
619 		if (lstat(abspath, &sb) == -1) {
620 			err = got_error_from_errno2("lstat", abspath);
621 		} else if (!S_ISDIR(sb.st_mode)) {
622 			/* TODO directory is obstructed; do something */
623 			err = got_error(GOT_ERR_FILE_OBSTRUCTED);
624 		}
625 	}
626 	free(abspath);
627 	return err;
628 }
629 
630 static const struct got_error *
631 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
632 {
633 	const struct got_error *err = NULL;
634 	uint8_t fbuf1[8192];
635 	uint8_t fbuf2[8192];
636 	size_t flen1 = 0, flen2 = 0;
637 
638 	*same = 1;
639 
640 	for (;;) {
641 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
642 		if (flen1 == 0 && ferror(f1)) {
643 			err = got_error_from_errno("fread");
644 			break;
645 		}
646 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
647 		if (flen2 == 0 && ferror(f2)) {
648 			err = got_error_from_errno("fread");
649 			break;
650 		}
651 		if (flen1 == 0) {
652 			if (flen2 != 0)
653 				*same = 0;
654 			break;
655 		} else if (flen2 == 0) {
656 			if (flen1 != 0)
657 				*same = 0;
658 			break;
659 		} else if (flen1 == flen2) {
660 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
661 				*same = 0;
662 				break;
663 			}
664 		} else {
665 			*same = 0;
666 			break;
667 		}
668 	}
669 
670 	return err;
671 }
672 
673 static const struct got_error *
674 check_files_equal(int *same, const char *f1_path, const char *f2_path)
675 {
676 	const struct got_error *err = NULL;
677 	struct stat sb;
678 	size_t size1, size2;
679 	FILE *f1 = NULL, *f2 = NULL;
680 
681 	*same = 1;
682 
683 	if (lstat(f1_path, &sb) != 0) {
684 		err = got_error_from_errno2("lstat", f1_path);
685 		goto done;
686 	}
687 	size1 = sb.st_size;
688 
689 	if (lstat(f2_path, &sb) != 0) {
690 		err = got_error_from_errno2("lstat", f2_path);
691 		goto done;
692 	}
693 	size2 = sb.st_size;
694 
695 	if (size1 != size2) {
696 		*same = 0;
697 		return NULL;
698 	}
699 
700 	f1 = fopen(f1_path, "r");
701 	if (f1 == NULL)
702 		return got_error_from_errno2("open", f1_path);
703 
704 	f2 = fopen(f2_path, "r");
705 	if (f2 == NULL) {
706 		err = got_error_from_errno2("open", f2_path);
707 		goto done;
708 	}
709 
710 	err = check_file_contents_equal(same, f1, f2);
711 done:
712 	if (f1 && fclose(f1) != 0 && err == NULL)
713 		err = got_error_from_errno("fclose");
714 	if (f2 && fclose(f2) != 0 && err == NULL)
715 		err = got_error_from_errno("fclose");
716 
717 	return err;
718 }
719 
720 /*
721  * Perform a 3-way merge where blob_orig acts as the common ancestor,
722  * blob_deriv acts as the first derived version, and the file on disk
723  * acts as the second derived version.
724  */
725 static const struct got_error *
726 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
727     struct got_blob_object *blob_orig, const char *ondisk_path,
728     const char *path, uint16_t st_mode, struct got_blob_object *blob_deriv,
729     struct got_object_id *deriv_base_commit_id,
730     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
731     void *progress_arg)
732 {
733 	const struct got_error *err = NULL;
734 	int merged_fd = -1;
735 	FILE *f_deriv = NULL, *f_orig = NULL;
736 	char *blob_deriv_path = NULL, *blob_orig_path = NULL;
737 	char *merged_path = NULL, *base_path = NULL;
738 	char *id_str = NULL;
739 	char *label_deriv = NULL;
740 	int overlapcnt = 0;
741 	char *parent;
742 
743 	*local_changes_subsumed = 0;
744 
745 	parent = dirname(ondisk_path);
746 	if (parent == NULL)
747 		return got_error_from_errno2("dirname", ondisk_path);
748 
749 	if (asprintf(&base_path, "%s/got-merged", parent) == -1)
750 		return got_error_from_errno("asprintf");
751 
752 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
753 	if (err)
754 		goto done;
755 
756 	free(base_path);
757 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
758 		err = got_error_from_errno("asprintf");
759 		base_path = NULL;
760 		goto done;
761 	}
762 
763 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path);
764 	if (err)
765 		goto done;
766 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
767 	    blob_deriv);
768 	if (err)
769 		goto done;
770 
771 	free(base_path);
772 	if (asprintf(&base_path, "%s/got-merge-blob-orig", parent) == -1) {
773 		err = got_error_from_errno("asprintf");
774 		base_path = NULL;
775 		goto done;
776 	}
777 
778 	err = got_opentemp_named(&blob_orig_path, &f_orig, base_path);
779 	if (err)
780 		goto done;
781 	if (blob_orig) {
782 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
783 		    blob_orig);
784 		if (err)
785 			goto done;
786 	} else {
787 		/*
788 		 * If the file has no blob, this is an "add vs add" conflict,
789 		 * and we simply use an empty ancestor file to make both files
790 		 * appear in the merged result in their entirety.
791 		 */
792 	}
793 
794 	err = got_object_id_str(&id_str, deriv_base_commit_id);
795 	if (err)
796 		goto done;
797 	if (asprintf(&label_deriv, "commit %s", id_str) == -1) {
798 		err = got_error_from_errno("asprintf");
799 		goto done;
800 	}
801 
802 	err = got_merge_diff3(&overlapcnt, merged_fd, blob_deriv_path,
803 	    blob_orig_path, ondisk_path, label_deriv, path);
804 	if (err)
805 		goto done;
806 
807 	err = (*progress_cb)(progress_arg,
808 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
809 	if (err)
810 		goto done;
811 
812 	if (fsync(merged_fd) != 0) {
813 		err = got_error_from_errno("fsync");
814 		goto done;
815 	}
816 
817 	/* Check if a clean merge has subsumed all local changes. */
818 	if (overlapcnt == 0) {
819 		err = check_files_equal(local_changes_subsumed, blob_deriv_path,
820 		    merged_path);
821 		if (err)
822 			goto done;
823 	}
824 
825 	if (chmod(merged_path, st_mode) != 0) {
826 		err = got_error_from_errno2("chmod", merged_path);
827 		goto done;
828 	}
829 
830 	if (rename(merged_path, ondisk_path) != 0) {
831 		err = got_error_from_errno3("rename", merged_path,
832 		    ondisk_path);
833 		unlink(merged_path);
834 		goto done;
835 	}
836 
837 done:
838 	if (merged_fd != -1 && close(merged_fd) != 0 && err == NULL)
839 		err = got_error_from_errno("close");
840 	if (f_deriv && fclose(f_deriv) != 0 && err == NULL)
841 		err = got_error_from_errno("fclose");
842 	if (f_orig && fclose(f_orig) != 0 && err == NULL)
843 		err = got_error_from_errno("fclose");
844 	free(merged_path);
845 	free(base_path);
846 	if (blob_deriv_path) {
847 		unlink(blob_deriv_path);
848 		free(blob_deriv_path);
849 	}
850 	if (blob_orig_path) {
851 		unlink(blob_orig_path);
852 		free(blob_orig_path);
853 	}
854 	free(id_str);
855 	free(label_deriv);
856 	return err;
857 }
858 
859 static const struct got_error *
860 update_blob_fileindex_entry(struct got_worktree *worktree,
861     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
862     const char *ondisk_path, const char *path, struct got_blob_object *blob,
863     int update_timestamps)
864 {
865 	const struct got_error *err = NULL;
866 
867 	if (ie == NULL)
868 		ie = got_fileindex_entry_get(fileindex, path, strlen(path));
869 	if (ie)
870 		err = got_fileindex_entry_update(ie, ondisk_path,
871 		    blob->id.sha1, worktree->base_commit_id->sha1,
872 		    update_timestamps);
873 	else {
874 		struct got_fileindex_entry *new_ie;
875 		err = got_fileindex_entry_alloc(&new_ie, ondisk_path,
876 		    path, blob->id.sha1, worktree->base_commit_id->sha1);
877 		if (!err)
878 			err = got_fileindex_entry_add(fileindex, new_ie);
879 	}
880 	return err;
881 }
882 
883 static const struct got_error *
884 install_blob(struct got_worktree *worktree, const char *ondisk_path,
885    const char *path, uint16_t te_mode, uint16_t st_mode,
886    struct got_blob_object *blob, int restoring_missing_file,
887    int reverting_versioned_file, struct got_repository *repo,
888    got_worktree_checkout_cb progress_cb, void *progress_arg)
889 {
890 	const struct got_error *err = NULL;
891 	int fd = -1;
892 	size_t len, hdrlen;
893 	int update = 0;
894 	char *tmppath = NULL;
895 
896 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
897 	    GOT_DEFAULT_FILE_MODE);
898 	if (fd == -1) {
899 		if (errno == ENOENT) {
900 			char *parent = dirname(path);
901 			if (parent == NULL)
902 				return got_error_from_errno2("dirname", path);
903 			err = add_dir_on_disk(worktree, parent);
904 			if (err)
905 				return err;
906 			fd = open(ondisk_path,
907 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
908 			    GOT_DEFAULT_FILE_MODE);
909 			if (fd == -1)
910 				return got_error_from_errno2("open",
911 				    ondisk_path);
912 		} else if (errno == EEXIST) {
913 			if (!S_ISREG(st_mode)) {
914 				/* TODO file is obstructed; do something */
915 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
916 				goto done;
917 			} else {
918 				err = got_opentemp_named_fd(&tmppath, &fd,
919 				    ondisk_path);
920 				if (err)
921 					goto done;
922 				update = 1;
923 			}
924 		} else
925 			return got_error_from_errno2("open", ondisk_path);
926 	}
927 
928 	if (restoring_missing_file)
929 		err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING, path);
930 	else if (reverting_versioned_file)
931 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, path);
932 	else
933 		err = (*progress_cb)(progress_arg,
934 		    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
935 	if (err)
936 		goto done;
937 
938 	hdrlen = got_object_blob_get_hdrlen(blob);
939 	do {
940 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
941 		err = got_object_blob_read_block(&len, blob);
942 		if (err)
943 			break;
944 		if (len > 0) {
945 			/* Skip blob object header first time around. */
946 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
947 			if (outlen == -1) {
948 				err = got_error_from_errno("write");
949 				goto done;
950 			} else if (outlen != len - hdrlen) {
951 				err = got_error(GOT_ERR_IO);
952 				goto done;
953 			}
954 			hdrlen = 0;
955 		}
956 	} while (len != 0);
957 
958 	if (fsync(fd) != 0) {
959 		err = got_error_from_errno("fsync");
960 		goto done;
961 	}
962 
963 	if (update) {
964 		if (rename(tmppath, ondisk_path) != 0) {
965 			err = got_error_from_errno3("rename", tmppath,
966 			    ondisk_path);
967 			unlink(tmppath);
968 			goto done;
969 		}
970 	}
971 
972 	if (te_mode & S_IXUSR) {
973 		if (chmod(ondisk_path, st_mode | S_IXUSR) == -1) {
974 			err = got_error_from_errno2("chmod", ondisk_path);
975 			goto done;
976 		}
977 	} else {
978 		if (chmod(ondisk_path, st_mode & ~S_IXUSR) == -1) {
979 			err = got_error_from_errno2("chmod", ondisk_path);
980 			goto done;
981 		}
982 	}
983 
984 done:
985 	if (fd != -1 && close(fd) != 0 && err == NULL)
986 		err = got_error_from_errno("close");
987 	free(tmppath);
988 	return err;
989 }
990 
991 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
992 static const struct got_error *
993 get_modified_file_content_status(unsigned char *status, FILE *f)
994 {
995 	const struct got_error *err = NULL;
996 	const char *markers[3] = {
997 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
998 		GOT_DIFF_CONFLICT_MARKER_SEP,
999 		GOT_DIFF_CONFLICT_MARKER_END
1000 	};
1001 	int i = 0;
1002 	char *line;
1003 	size_t len;
1004 	const char delim[3] = {'\0', '\0', '\0'};
1005 
1006 	while (*status == GOT_STATUS_MODIFY) {
1007 		line = fparseln(f, &len, NULL, delim, 0);
1008 		if (line == NULL) {
1009 			if (feof(f))
1010 				break;
1011 			err = got_ferror(f, GOT_ERR_IO);
1012 			break;
1013 		}
1014 
1015 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1016 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1017 			    == 0)
1018 				*status = GOT_STATUS_CONFLICT;
1019 			else
1020 				i++;
1021 		}
1022 	}
1023 
1024 	return err;
1025 }
1026 
1027 static int
1028 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1029 {
1030 	return !(ie->ctime_sec == sb->st_ctime &&
1031 	    ie->ctime_nsec == sb->st_ctimensec &&
1032 	    ie->mtime_sec == sb->st_mtime &&
1033 	    ie->mtime_nsec == sb->st_mtimensec &&
1034 	    ie->size == (sb->st_size & 0xffffffff));
1035 }
1036 
1037 static const struct got_error *
1038 get_file_status(unsigned char *status, struct stat *sb,
1039     struct got_fileindex_entry *ie, const char *abspath,
1040     struct got_repository *repo)
1041 {
1042 	const struct got_error *err = NULL;
1043 	struct got_object_id id;
1044 	size_t hdrlen;
1045 	FILE *f = NULL;
1046 	uint8_t fbuf[8192];
1047 	struct got_blob_object *blob = NULL;
1048 	size_t flen, blen;
1049 
1050 	*status = GOT_STATUS_NO_CHANGE;
1051 
1052 	if (lstat(abspath, sb) == -1) {
1053 		if (errno == ENOENT) {
1054 			if (got_fileindex_entry_has_file_on_disk(ie))
1055 				*status = GOT_STATUS_MISSING;
1056 			else
1057 				*status = GOT_STATUS_DELETE;
1058 			return NULL;
1059 		}
1060 		return got_error_from_errno2("lstat", abspath);
1061 	}
1062 
1063 	if (!S_ISREG(sb->st_mode)) {
1064 		*status = GOT_STATUS_OBSTRUCTED;
1065 		return NULL;
1066 	}
1067 
1068 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1069 		*status = GOT_STATUS_DELETE;
1070 		return NULL;
1071 	} else if (!got_fileindex_entry_has_blob(ie)) {
1072 		*status = GOT_STATUS_ADD;
1073 		return NULL;
1074 	}
1075 
1076 	if (!stat_info_differs(ie, sb))
1077 		return NULL;
1078 
1079 	memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1080 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1081 	if (err)
1082 		return err;
1083 
1084 	f = fopen(abspath, "r");
1085 	if (f == NULL) {
1086 		err = got_error_from_errno2("fopen", abspath);
1087 		goto done;
1088 	}
1089 	hdrlen = got_object_blob_get_hdrlen(blob);
1090 	for (;;) {
1091 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1092 		err = got_object_blob_read_block(&blen, blob);
1093 		if (err)
1094 			goto done;
1095 		/* Skip length of blob object header first time around. */
1096 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1097 		if (flen == 0 && ferror(f)) {
1098 			err = got_error_from_errno("fread");
1099 			goto done;
1100 		}
1101 		if (blen == 0) {
1102 			if (flen != 0)
1103 				*status = GOT_STATUS_MODIFY;
1104 			break;
1105 		} else if (flen == 0) {
1106 			if (blen != 0)
1107 				*status = GOT_STATUS_MODIFY;
1108 			break;
1109 		} else if (blen - hdrlen == flen) {
1110 			/* Skip blob object header first time around. */
1111 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1112 				*status = GOT_STATUS_MODIFY;
1113 				break;
1114 			}
1115 		} else {
1116 			*status = GOT_STATUS_MODIFY;
1117 			break;
1118 		}
1119 		hdrlen = 0;
1120 	}
1121 
1122 	if (*status == GOT_STATUS_MODIFY) {
1123 		rewind(f);
1124 		err = get_modified_file_content_status(status, f);
1125 	}
1126 done:
1127 	if (blob)
1128 		got_object_blob_close(blob);
1129 	if (f)
1130 		fclose(f);
1131 	return err;
1132 }
1133 
1134 /*
1135  * Update timestamps in the file index if a file is unmodified and
1136  * we had to run a full content comparison to find out.
1137  */
1138 static const struct got_error *
1139 sync_timestamps(char *ondisk_path, unsigned char status,
1140     struct got_fileindex_entry *ie, struct stat *sb)
1141 {
1142 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1143 		return got_fileindex_entry_update(ie, ondisk_path,
1144 		    ie->blob_sha1, ie->commit_sha1, 1);
1145 
1146 	return NULL;
1147 }
1148 
1149 static const struct got_error *
1150 update_blob(struct got_worktree *worktree,
1151     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1152     struct got_tree_entry *te, const char *path,
1153     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1154     void *progress_arg)
1155 {
1156 	const struct got_error *err = NULL;
1157 	struct got_blob_object *blob = NULL;
1158 	char *ondisk_path;
1159 	unsigned char status = GOT_STATUS_NO_CHANGE;
1160 	struct stat sb;
1161 
1162 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1163 		return got_error_from_errno("asprintf");
1164 
1165 	if (ie) {
1166 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1167 		if (err)
1168 			goto done;
1169 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1170 			sb.st_mode = got_fileindex_perms_to_st(ie);
1171 	} else
1172 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
1173 
1174 	if (status == GOT_STATUS_OBSTRUCTED) {
1175 		err = (*progress_cb)(progress_arg, status, path);
1176 		goto done;
1177 	}
1178 
1179 	if (ie && status != GOT_STATUS_MISSING) {
1180 		if (got_fileindex_entry_has_commit(ie) &&
1181 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1182 		    SHA1_DIGEST_LENGTH) == 0) {
1183 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1184 			if (err)
1185 				goto done;
1186 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1187 			    path);
1188 			goto done;
1189 		}
1190 		if (got_fileindex_entry_has_blob(ie) &&
1191 		    memcmp(ie->blob_sha1, te->id->sha1,
1192 		    SHA1_DIGEST_LENGTH) == 0) {
1193 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1194 			goto done;
1195 		}
1196 	}
1197 
1198 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1199 	if (err)
1200 		goto done;
1201 
1202 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1203 		int update_timestamps;
1204 		struct got_blob_object *blob2 = NULL;
1205 		if (got_fileindex_entry_has_blob(ie)) {
1206 			struct got_object_id id2;
1207 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1208 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
1209 			if (err)
1210 				goto done;
1211 		}
1212 		err = merge_blob(&update_timestamps, worktree, blob2,
1213 		    ondisk_path, path, sb.st_mode, blob,
1214 		    worktree->base_commit_id, repo,
1215 		    progress_cb, progress_arg);
1216 		if (blob2)
1217 			got_object_blob_close(blob2);
1218 		/*
1219 		 * Do not update timestamps of files with local changes.
1220 		 * Otherwise, a future status walk would treat them as
1221 		 * unmodified files again.
1222 		 */
1223 		err = got_fileindex_entry_update(ie, ondisk_path,
1224 		    blob->id.sha1, worktree->base_commit_id->sha1,
1225 		    update_timestamps);
1226 	} else if (status == GOT_STATUS_DELETE) {
1227 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1228 		if (err)
1229 			goto done;
1230 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1231 		    ondisk_path, path, blob, 0);
1232 		if (err)
1233 			goto done;
1234 	} else {
1235 		err = install_blob(worktree, ondisk_path, path, te->mode,
1236 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1237 		    repo, progress_cb, progress_arg);
1238 		if (err)
1239 			goto done;
1240 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1241 		    ondisk_path, path, blob, 1);
1242 		if (err)
1243 			goto done;
1244 	}
1245 	got_object_blob_close(blob);
1246 done:
1247 	free(ondisk_path);
1248 	return err;
1249 }
1250 
1251 static const struct got_error *
1252 remove_ondisk_file(const char *root_path, const char *path)
1253 {
1254 	const struct got_error *err = NULL;
1255 	char *ondisk_path = NULL;
1256 
1257 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1258 		return got_error_from_errno("asprintf");
1259 
1260 	if (unlink(ondisk_path) == -1) {
1261 		if (errno != ENOENT)
1262 			err = got_error_from_errno2("unlink", ondisk_path);
1263 	} else {
1264 		char *parent = dirname(ondisk_path);
1265 		while (parent && strcmp(parent, root_path) != 0) {
1266 			if (rmdir(parent) == -1) {
1267 				if (errno != ENOTEMPTY)
1268 					err = got_error_from_errno2("rmdir",
1269 					    parent);
1270 				break;
1271 			}
1272 			parent = dirname(parent);
1273 		}
1274 	}
1275 	free(ondisk_path);
1276 	return err;
1277 }
1278 
1279 static const struct got_error *
1280 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1281     struct got_fileindex_entry *ie, struct got_repository *repo,
1282     got_worktree_checkout_cb progress_cb, void *progress_arg)
1283 {
1284 	const struct got_error *err = NULL;
1285 	unsigned char status;
1286 	struct stat sb;
1287 	char *ondisk_path;
1288 
1289 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1290 	    == -1)
1291 		return got_error_from_errno("asprintf");
1292 
1293 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1294 	if (err)
1295 		return err;
1296 
1297 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1298 	    status == GOT_STATUS_ADD) {
1299 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1300 		if (err)
1301 			return err;
1302 		/*
1303 		 * Preserve the working file and change the deleted blob's
1304 		 * entry into a schedule-add entry.
1305 		 */
1306 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1307 		    0);
1308 		if (err)
1309 			return err;
1310 	} else {
1311 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1312 		if (err)
1313 			return err;
1314 		if (status == GOT_STATUS_NO_CHANGE) {
1315 			err = remove_ondisk_file(worktree->root_path, ie->path);
1316 			if (err)
1317 				return err;
1318 		}
1319 		got_fileindex_entry_remove(fileindex, ie);
1320 	}
1321 
1322 	return err;
1323 }
1324 
1325 struct diff_cb_arg {
1326     struct got_fileindex *fileindex;
1327     struct got_worktree *worktree;
1328     struct got_repository *repo;
1329     got_worktree_checkout_cb progress_cb;
1330     void *progress_arg;
1331     got_worktree_cancel_cb cancel_cb;
1332     void *cancel_arg;
1333 };
1334 
1335 static const struct got_error *
1336 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1337     struct got_tree_entry *te, const char *parent_path)
1338 {
1339 	struct diff_cb_arg *a = arg;
1340 
1341 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1342 		return got_error(GOT_ERR_CANCELLED);
1343 
1344 	return update_blob(a->worktree, a->fileindex, ie, te,
1345 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1346 }
1347 
1348 static const struct got_error *
1349 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1350 {
1351 	struct diff_cb_arg *a = arg;
1352 
1353 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1354 		return got_error(GOT_ERR_CANCELLED);
1355 
1356 	return delete_blob(a->worktree, a->fileindex, ie,
1357 	    a->repo, a->progress_cb, a->progress_arg);
1358 }
1359 
1360 static const struct got_error *
1361 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1362 {
1363 	struct diff_cb_arg *a = arg;
1364 	const struct got_error *err;
1365 	char *path;
1366 
1367 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1368 		return got_error(GOT_ERR_CANCELLED);
1369 
1370 	if (asprintf(&path, "%s%s%s", parent_path,
1371 	    parent_path[0] ? "/" : "", te->name)
1372 	    == -1)
1373 		return got_error_from_errno("asprintf");
1374 
1375 	if (S_ISDIR(te->mode))
1376 		err = add_dir_on_disk(a->worktree, path);
1377 	else
1378 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1379 		    a->repo, a->progress_cb, a->progress_arg);
1380 
1381 	free(path);
1382 	return err;
1383 }
1384 
1385 static const struct got_error *
1386 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
1387 {
1388 	const struct got_error *err = NULL;
1389 	char *uuidstr = NULL;
1390 	uint32_t uuid_status;
1391 
1392 	*refname = NULL;
1393 
1394 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1395 	if (uuid_status != uuid_s_ok)
1396 		return got_error_uuid(uuid_status);
1397 
1398 	if (asprintf(refname, "%s-%s", prefix, uuidstr)
1399 	    == -1) {
1400 		err = got_error_from_errno("asprintf");
1401 		*refname = NULL;
1402 	}
1403 	free(uuidstr);
1404 	return err;
1405 }
1406 
1407 const struct got_error *
1408 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1409 {
1410 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
1411 }
1412 
1413 static const struct got_error *
1414 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
1415 {
1416 	return get_ref_name(refname, worktree,
1417 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
1418 }
1419 
1420 static const struct got_error *
1421 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
1422 {
1423 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
1424 }
1425 
1426 static const struct got_error *
1427 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
1428 {
1429 	return get_ref_name(refname, worktree,
1430 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
1431 }
1432 
1433 static const struct got_error *
1434 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
1435 {
1436 	return get_ref_name(refname, worktree,
1437 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
1438 }
1439 
1440 static const struct got_error *
1441 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
1442 {
1443 	return get_ref_name(refname, worktree,
1444 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
1445 }
1446 
1447 static const struct got_error *
1448 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
1449 {
1450 	return get_ref_name(refname, worktree,
1451 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
1452 }
1453 
1454 static const struct got_error *
1455 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
1456 {
1457 	return get_ref_name(refname, worktree,
1458 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
1459 }
1460 
1461 static const struct got_error *
1462 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
1463 {
1464 	return get_ref_name(refname, worktree,
1465 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
1466 }
1467 
1468 const struct got_error *
1469 got_worktree_get_histedit_script_path(char **path,
1470     struct got_worktree *worktree)
1471 {
1472 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
1473 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
1474 		*path = NULL;
1475 		return got_error_from_errno("asprintf");
1476 	}
1477 	return NULL;
1478 }
1479 
1480 /*
1481  * Prevent Git's garbage collector from deleting our base commit by
1482  * setting a reference to our base commit's ID.
1483  */
1484 static const struct got_error *
1485 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1486 {
1487 	const struct got_error *err = NULL;
1488 	struct got_reference *ref = NULL;
1489 	char *refname;
1490 
1491 	err = got_worktree_get_base_ref_name(&refname, worktree);
1492 	if (err)
1493 		return err;
1494 
1495 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1496 	if (err)
1497 		goto done;
1498 
1499 	err = got_ref_write(ref, repo);
1500 done:
1501 	free(refname);
1502 	if (ref)
1503 		got_ref_close(ref);
1504 	return err;
1505 }
1506 
1507 static const struct got_error *
1508 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
1509 {
1510 	const struct got_error *err = NULL;
1511 
1512 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1513 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1514 		err = got_error_from_errno("asprintf");
1515 		*fileindex_path = NULL;
1516 	}
1517 	return err;
1518 }
1519 
1520 
1521 static const struct got_error *
1522 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1523    struct got_worktree *worktree)
1524 {
1525 	const struct got_error *err = NULL;
1526 	FILE *index = NULL;
1527 
1528 	*fileindex_path = NULL;
1529 	*fileindex = got_fileindex_alloc();
1530 	if (*fileindex == NULL)
1531 		return got_error_from_errno("got_fileindex_alloc");
1532 
1533 	err = get_fileindex_path(fileindex_path, worktree);
1534 	if (err)
1535 		goto done;
1536 
1537 	index = fopen(*fileindex_path, "rb");
1538 	if (index == NULL) {
1539 		if (errno != ENOENT)
1540 			err = got_error_from_errno2("fopen", *fileindex_path);
1541 	} else {
1542 		err = got_fileindex_read(*fileindex, index);
1543 		if (fclose(index) != 0 && err == NULL)
1544 			err = got_error_from_errno("fclose");
1545 	}
1546 done:
1547 	if (err) {
1548 		free(*fileindex_path);
1549 		*fileindex_path = NULL;
1550 		got_fileindex_free(*fileindex);
1551 		*fileindex = NULL;
1552 	}
1553 	return err;
1554 }
1555 
1556 struct bump_base_commit_id_arg {
1557 	struct got_object_id *base_commit_id;
1558 	const char *path;
1559 	size_t path_len;
1560 	const char *entry_name;
1561 	got_worktree_checkout_cb progress_cb;
1562 	void *progress_arg;
1563 };
1564 
1565 /* Bump base commit ID of all files within an updated part of the work tree. */
1566 static const struct got_error *
1567 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1568 {
1569 	const struct got_error *err;
1570 	struct bump_base_commit_id_arg *a = arg;
1571 
1572 	if (a->entry_name) {
1573 		if (strcmp(ie->path, a->path) != 0)
1574 			return NULL;
1575 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1576 		return NULL;
1577 
1578 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
1579 	    SHA1_DIGEST_LENGTH) == 0)
1580 		return NULL;
1581 
1582 	if (a->progress_cb) {
1583 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
1584 		    ie->path);
1585 		if (err)
1586 			return err;
1587 	}
1588 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1589 	return NULL;
1590 }
1591 
1592 static const struct got_error *
1593 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
1594 {
1595 	const struct got_error *err = NULL;
1596 	char *new_fileindex_path = NULL;
1597 	FILE *new_index = NULL;
1598 
1599 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1600 	    fileindex_path);
1601 	if (err)
1602 		goto done;
1603 
1604 	err = got_fileindex_write(fileindex, new_index);
1605 	if (err)
1606 		goto done;
1607 
1608 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1609 		err = got_error_from_errno3("rename", new_fileindex_path,
1610 		    fileindex_path);
1611 		unlink(new_fileindex_path);
1612 	}
1613 done:
1614 	if (new_index)
1615 		fclose(new_index);
1616 	free(new_fileindex_path);
1617 	return err;
1618 }
1619 
1620 static const struct got_error *
1621 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
1622     struct got_object_id **tree_id, const char *wt_relpath,
1623     struct got_worktree *worktree, struct got_repository *repo)
1624 {
1625 	const struct got_error *err = NULL;
1626 	struct got_object_id *id = NULL;
1627 	char *in_repo_path = NULL;
1628 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
1629 
1630 	*entry_type = GOT_OBJ_TYPE_ANY;
1631 	*tree_relpath = NULL;
1632 	*tree_id = NULL;
1633 
1634 	if (wt_relpath[0] == '\0') {
1635 		/* Check out all files within the work tree. */
1636 		*entry_type = GOT_OBJ_TYPE_TREE;
1637 		*tree_relpath = strdup("");
1638 		if (*tree_relpath == NULL) {
1639 			err = got_error_from_errno("strdup");
1640 			goto done;
1641 		}
1642 		err = got_object_id_by_path(tree_id, repo,
1643 		    worktree->base_commit_id, worktree->path_prefix);
1644 		if (err)
1645 			goto done;
1646 		return NULL;
1647 	}
1648 
1649 	/* Check out a subset of files in the work tree. */
1650 
1651 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
1652 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
1653 		err = got_error_from_errno("asprintf");
1654 		goto done;
1655 	}
1656 
1657 	err = got_object_id_by_path(&id, repo, worktree->base_commit_id,
1658 	    in_repo_path);
1659 	if (err)
1660 		goto done;
1661 
1662 	free(in_repo_path);
1663 	in_repo_path = NULL;
1664 
1665 	err = got_object_get_type(entry_type, repo, id);
1666 	if (err)
1667 		goto done;
1668 
1669 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
1670 		/* Check out a single file. */
1671 		if (strchr(wt_relpath, '/')  == NULL) {
1672 			/* Check out a single file in work tree's root dir. */
1673 			in_repo_path = strdup(worktree->path_prefix);
1674 			if (in_repo_path == NULL) {
1675 				err = got_error_from_errno("strdup");
1676 				goto done;
1677 			}
1678 			*tree_relpath = strdup("");
1679 			if (*tree_relpath == NULL) {
1680 				err = got_error_from_errno("strdup");
1681 				goto done;
1682 			}
1683 		} else {
1684 			/* Check out a single file in a subdirectory. */
1685 			err = got_path_dirname(tree_relpath, wt_relpath);
1686 			if (err)
1687 				return err;
1688 			if (asprintf(&in_repo_path, "%s%s%s",
1689 			    worktree->path_prefix, is_root_wt ? "" : "/",
1690 			    *tree_relpath) == -1) {
1691 				err = got_error_from_errno("asprintf");
1692 				goto done;
1693 			}
1694 		}
1695 		err = got_object_id_by_path(tree_id, repo,
1696 		    worktree->base_commit_id, in_repo_path);
1697 	} else {
1698 		/* Check out all files within a subdirectory. */
1699 		*tree_id = got_object_id_dup(id);
1700 		if (*tree_id == NULL) {
1701 			err = got_error_from_errno("got_object_id_dup");
1702 			goto done;
1703 		}
1704 		*tree_relpath = strdup(wt_relpath);
1705 		if (*tree_relpath == NULL) {
1706 			err = got_error_from_errno("strdup");
1707 			goto done;
1708 		}
1709 	}
1710 done:
1711 	free(id);
1712 	free(in_repo_path);
1713 	if (err) {
1714 		*entry_type = GOT_OBJ_TYPE_ANY;
1715 		free(*tree_relpath);
1716 		*tree_relpath = NULL;
1717 		free(*tree_id);
1718 		*tree_id = NULL;
1719 	}
1720 	return err;
1721 }
1722 
1723 static const struct got_error *
1724 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
1725     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
1726     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1727     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1728 {
1729 	const struct got_error *err = NULL;
1730 	struct got_commit_object *commit = NULL;
1731 	struct got_tree_object *tree = NULL;
1732 	struct got_fileindex_diff_tree_cb diff_cb;
1733 	struct diff_cb_arg arg;
1734 
1735 	err = ref_base_commit(worktree, repo);
1736 	if (err)
1737 		goto done;
1738 
1739 	err = got_object_open_as_commit(&commit, repo,
1740 	   worktree->base_commit_id);
1741 	if (err)
1742 		goto done;
1743 
1744 	err = got_object_open_as_tree(&tree, repo, tree_id);
1745 	if (err)
1746 		goto done;
1747 
1748 	if (entry_name &&
1749 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1750 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1751 		goto done;
1752 	}
1753 
1754 	diff_cb.diff_old_new = diff_old_new;
1755 	diff_cb.diff_old = diff_old;
1756 	diff_cb.diff_new = diff_new;
1757 	arg.fileindex = fileindex;
1758 	arg.worktree = worktree;
1759 	arg.repo = repo;
1760 	arg.progress_cb = progress_cb;
1761 	arg.progress_arg = progress_arg;
1762 	arg.cancel_cb = cancel_cb;
1763 	arg.cancel_arg = cancel_arg;
1764 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
1765 	    entry_name, repo, &diff_cb, &arg);
1766 done:
1767 	if (tree)
1768 		got_object_tree_close(tree);
1769 	if (commit)
1770 		got_object_commit_close(commit);
1771 	return err;
1772 }
1773 
1774 const struct got_error *
1775 got_worktree_checkout_files(struct got_worktree *worktree,
1776     struct got_pathlist_head *paths, struct got_repository *repo,
1777     got_worktree_checkout_cb progress_cb, void *progress_arg,
1778     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1779 {
1780 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1781 	struct got_commit_object *commit = NULL;
1782 	struct got_tree_object *tree = NULL;
1783 	struct got_fileindex *fileindex = NULL;
1784 	char *fileindex_path = NULL;
1785 	struct got_pathlist_entry *pe;
1786 	struct tree_path_data {
1787 		SIMPLEQ_ENTRY(tree_path_data) entry;
1788 		struct got_object_id *tree_id;
1789 		int entry_type;
1790 		char *relpath;
1791 		char *entry_name;
1792 	} *tpd = NULL;
1793 	SIMPLEQ_HEAD(tree_paths, tree_path_data) tree_paths;
1794 
1795 	SIMPLEQ_INIT(&tree_paths);
1796 
1797 	err = lock_worktree(worktree, LOCK_EX);
1798 	if (err)
1799 		return err;
1800 
1801 	/* Map all specified paths to in-repository trees. */
1802 	TAILQ_FOREACH(pe, paths, entry) {
1803 		tpd = malloc(sizeof(*tpd));
1804 		if (tpd == NULL) {
1805 			err = got_error_from_errno("malloc");
1806 			goto done;
1807 		}
1808 
1809 		err = find_tree_entry_for_checkout(&tpd->entry_type,
1810 		    &tpd->relpath, &tpd->tree_id, pe->path, worktree, repo);
1811 		if (err) {
1812 			free(tpd);
1813 			goto done;
1814 		}
1815 
1816 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
1817 			err = got_path_basename(&tpd->entry_name, pe->path);
1818 			if (err) {
1819 				free(tpd->relpath);
1820 				free(tpd->tree_id);
1821 				free(tpd);
1822 				goto done;
1823 			}
1824 		} else
1825 			tpd->entry_name = NULL;
1826 
1827 		SIMPLEQ_INSERT_TAIL(&tree_paths, tpd, entry);
1828 	}
1829 
1830 	/*
1831 	 * Read the file index.
1832 	 * Checking out files is supposed to be an idempotent operation.
1833 	 * If the on-disk file index is incomplete we will try to complete it.
1834 	 */
1835 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1836 	if (err)
1837 		goto done;
1838 
1839 	tpd = SIMPLEQ_FIRST(&tree_paths);
1840 	TAILQ_FOREACH(pe, paths, entry) {
1841 		struct bump_base_commit_id_arg bbc_arg;
1842 
1843 		err = checkout_files(worktree, fileindex, tpd->relpath,
1844 		    tpd->tree_id, tpd->entry_name, repo,
1845 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
1846 		if (err)
1847 			break;
1848 
1849 		bbc_arg.base_commit_id = worktree->base_commit_id;
1850 		bbc_arg.entry_name = tpd->entry_name;
1851 		bbc_arg.path = pe->path;
1852 		bbc_arg.path_len = pe->path_len;
1853 		bbc_arg.progress_cb = progress_cb;
1854 		bbc_arg.progress_arg = progress_arg;
1855 		err = got_fileindex_for_each_entry_safe(fileindex,
1856 		    bump_base_commit_id, &bbc_arg);
1857 		if (err)
1858 			break;
1859 
1860 		tpd = SIMPLEQ_NEXT(tpd, entry);
1861 	}
1862 	sync_err = sync_fileindex(fileindex, fileindex_path);
1863 	if (sync_err && err == NULL)
1864 		err = sync_err;
1865 done:
1866 	free(fileindex_path);
1867 	if (tree)
1868 		got_object_tree_close(tree);
1869 	if (commit)
1870 		got_object_commit_close(commit);
1871 	if (fileindex)
1872 		got_fileindex_free(fileindex);
1873 	while (!SIMPLEQ_EMPTY(&tree_paths)) {
1874 		tpd = SIMPLEQ_FIRST(&tree_paths);
1875 		SIMPLEQ_REMOVE_HEAD(&tree_paths, entry);
1876 		free(tpd->relpath);
1877 		free(tpd->tree_id);
1878 		free(tpd);
1879 	}
1880 	unlockerr = lock_worktree(worktree, LOCK_SH);
1881 	if (unlockerr && err == NULL)
1882 		err = unlockerr;
1883 	return err;
1884 }
1885 
1886 struct merge_file_cb_arg {
1887     struct got_worktree *worktree;
1888     struct got_fileindex *fileindex;
1889     got_worktree_checkout_cb progress_cb;
1890     void *progress_arg;
1891     got_worktree_cancel_cb cancel_cb;
1892     void *cancel_arg;
1893     struct got_object_id *commit_id2;
1894 };
1895 
1896 static const struct got_error *
1897 merge_file_cb(void *arg, struct got_blob_object *blob1,
1898     struct got_blob_object *blob2, struct got_object_id *id1,
1899     struct got_object_id *id2, const char *path1, const char *path2,
1900     struct got_repository *repo)
1901 {
1902 	static const struct got_error *err = NULL;
1903 	struct merge_file_cb_arg *a = arg;
1904 	struct got_fileindex_entry *ie;
1905 	char *ondisk_path = NULL;
1906 	struct stat sb;
1907 	unsigned char status;
1908 	int local_changes_subsumed;
1909 
1910 	if (blob1 && blob2) {
1911 		ie = got_fileindex_entry_get(a->fileindex, path2,
1912 		    strlen(path2));
1913 		if (ie == NULL)
1914 			return (*a->progress_cb)(a->progress_arg,
1915 			    GOT_STATUS_MISSING, path2);
1916 
1917 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1918 		    path2) == -1)
1919 			return got_error_from_errno("asprintf");
1920 
1921 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1922 		if (err)
1923 			goto done;
1924 
1925 		if (status == GOT_STATUS_DELETE) {
1926 			err = (*a->progress_cb)(a->progress_arg,
1927 			    GOT_STATUS_MERGE, path2);
1928 			goto done;
1929 		}
1930 		if (status != GOT_STATUS_NO_CHANGE &&
1931 		    status != GOT_STATUS_MODIFY &&
1932 		    status != GOT_STATUS_CONFLICT &&
1933 		    status != GOT_STATUS_ADD) {
1934 			err = (*a->progress_cb)(a->progress_arg, status, path2);
1935 			goto done;
1936 		}
1937 
1938 		err = merge_blob(&local_changes_subsumed, a->worktree, blob1,
1939 		    ondisk_path, path2, sb.st_mode, blob2, a->commit_id2, repo,
1940 		    a->progress_cb, a->progress_arg);
1941 	} else if (blob1) {
1942 		ie = got_fileindex_entry_get(a->fileindex, path1,
1943 		    strlen(path1));
1944 		if (ie == NULL)
1945 			return (*a->progress_cb)(a->progress_arg,
1946 			    GOT_STATUS_MISSING, path2);
1947 
1948 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1949 		    path1) == -1)
1950 			return got_error_from_errno("asprintf");
1951 
1952 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1953 		if (err)
1954 			goto done;
1955 
1956 		switch (status) {
1957 		case GOT_STATUS_NO_CHANGE:
1958 			err = (*a->progress_cb)(a->progress_arg,
1959 			    GOT_STATUS_DELETE, path1);
1960 			if (err)
1961 				goto done;
1962 			err = remove_ondisk_file(a->worktree->root_path, path1);
1963 			if (err)
1964 				goto done;
1965 			if (ie)
1966 				got_fileindex_entry_mark_deleted_from_disk(ie);
1967 			break;
1968 		case GOT_STATUS_DELETE:
1969 		case GOT_STATUS_MISSING:
1970 			err = (*a->progress_cb)(a->progress_arg,
1971 			    GOT_STATUS_DELETE, path1);
1972 			if (err)
1973 				goto done;
1974 			if (ie)
1975 				got_fileindex_entry_mark_deleted_from_disk(ie);
1976 			break;
1977 		case GOT_STATUS_ADD:
1978 		case GOT_STATUS_MODIFY:
1979 		case GOT_STATUS_CONFLICT:
1980 			err = (*a->progress_cb)(a->progress_arg,
1981 			    GOT_STATUS_CANNOT_DELETE, path1);
1982 			if (err)
1983 				goto done;
1984 			break;
1985 		case GOT_STATUS_OBSTRUCTED:
1986 			err = (*a->progress_cb)(a->progress_arg, status, path1);
1987 			if (err)
1988 				goto done;
1989 			break;
1990 		default:
1991 			break;
1992 		}
1993 	} else if (blob2) {
1994 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1995 		    path2) == -1)
1996 			return got_error_from_errno("asprintf");
1997 		ie = got_fileindex_entry_get(a->fileindex, path2,
1998 		    strlen(path2));
1999 		if (ie) {
2000 			err = get_file_status(&status, &sb, ie, ondisk_path,
2001 			    repo);
2002 			if (err)
2003 				goto done;
2004 			if (status != GOT_STATUS_NO_CHANGE &&
2005 			    status != GOT_STATUS_MODIFY &&
2006 			    status != GOT_STATUS_CONFLICT &&
2007 			    status != GOT_STATUS_ADD) {
2008 				err = (*a->progress_cb)(a->progress_arg,
2009 				    status, path2);
2010 				goto done;
2011 			}
2012 			err = merge_blob(&local_changes_subsumed, a->worktree,
2013 			    NULL, ondisk_path, path2, sb.st_mode, blob2,
2014 			    a->commit_id2, repo,
2015 			    a->progress_cb, a->progress_arg);
2016 			if (status == GOT_STATUS_DELETE) {
2017 				err = update_blob_fileindex_entry(a->worktree,
2018 				    a->fileindex, ie, ondisk_path, ie->path,
2019 				    blob2, 0);
2020 				if (err)
2021 					goto done;
2022 			}
2023 		} else {
2024 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
2025 			err = install_blob(a->worktree, ondisk_path, path2,
2026 			    /* XXX get this from parent tree! */
2027 			    GOT_DEFAULT_FILE_MODE,
2028 			    sb.st_mode, blob2, 0, 0, repo,
2029 			    a->progress_cb, a->progress_arg);
2030 			if (err)
2031 				goto done;
2032 			err = got_fileindex_entry_alloc(&ie,
2033 			    ondisk_path, path2, NULL, NULL);
2034 			if (err)
2035 				goto done;
2036 			err = got_fileindex_entry_add(a->fileindex, ie);
2037 			if (err) {
2038 				got_fileindex_entry_free(ie);
2039 				goto done;
2040 			}
2041 		}
2042 	}
2043 done:
2044 	free(ondisk_path);
2045 	return err;
2046 }
2047 
2048 struct check_merge_ok_arg {
2049 	struct got_worktree *worktree;
2050 	struct got_repository *repo;
2051 };
2052 
2053 static const struct got_error *
2054 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
2055 {
2056 	const struct got_error *err = NULL;
2057 	struct check_merge_ok_arg *a = arg;
2058 	unsigned char status;
2059 	struct stat sb;
2060 	char *ondisk_path;
2061 
2062 	/* Reject merges into a work tree with mixed base commits. */
2063 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
2064 	    SHA1_DIGEST_LENGTH))
2065 		return got_error(GOT_ERR_MIXED_COMMITS);
2066 
2067 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
2068 	    == -1)
2069 		return got_error_from_errno("asprintf");
2070 
2071 	/* Reject merges into a work tree with conflicted files. */
2072 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
2073 	if (err)
2074 		return err;
2075 	if (status == GOT_STATUS_CONFLICT)
2076 		return got_error(GOT_ERR_CONFLICTS);
2077 
2078 	return NULL;
2079 }
2080 
2081 static const struct got_error *
2082 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2083     const char *fileindex_path, struct got_object_id *commit_id1,
2084     struct got_object_id *commit_id2, struct got_repository *repo,
2085     got_worktree_checkout_cb progress_cb, void *progress_arg,
2086     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2087 {
2088 	const struct got_error *err = NULL, *sync_err;
2089 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
2090 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
2091 	struct merge_file_cb_arg arg;
2092 
2093 	if (commit_id1) {
2094 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
2095 		    worktree->path_prefix);
2096 		if (err)
2097 			goto done;
2098 
2099 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
2100 		if (err)
2101 			goto done;
2102 	}
2103 
2104 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
2105 	    worktree->path_prefix);
2106 	if (err)
2107 		goto done;
2108 
2109 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
2110 	if (err)
2111 		goto done;
2112 
2113 	arg.worktree = worktree;
2114 	arg.fileindex = fileindex;
2115 	arg.progress_cb = progress_cb;
2116 	arg.progress_arg = progress_arg;
2117 	arg.cancel_cb = cancel_cb;
2118 	arg.cancel_arg = cancel_arg;
2119 	arg.commit_id2 = commit_id2;
2120 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg, 1);
2121 	sync_err = sync_fileindex(fileindex, fileindex_path);
2122 	if (sync_err && err == NULL)
2123 		err = sync_err;
2124 done:
2125 	if (tree1)
2126 		got_object_tree_close(tree1);
2127 	if (tree2)
2128 		got_object_tree_close(tree2);
2129 	return err;
2130 }
2131 
2132 const struct got_error *
2133 got_worktree_merge_files(struct got_worktree *worktree,
2134     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
2135     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2136     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2137 {
2138 	const struct got_error *err, *unlockerr;
2139 	char *fileindex_path = NULL;
2140 	struct got_fileindex *fileindex = NULL;
2141 	struct check_merge_ok_arg mok_arg;
2142 
2143 	err = lock_worktree(worktree, LOCK_EX);
2144 	if (err)
2145 		return err;
2146 
2147 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2148 	if (err)
2149 		goto done;
2150 
2151 	mok_arg.worktree = worktree;
2152 	mok_arg.repo = repo;
2153 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
2154 	    &mok_arg);
2155 	if (err)
2156 		goto done;
2157 
2158 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
2159 	    commit_id2, repo, progress_cb, progress_arg, cancel_cb, cancel_arg);
2160 done:
2161 	if (fileindex)
2162 		got_fileindex_free(fileindex);
2163 	free(fileindex_path);
2164 	unlockerr = lock_worktree(worktree, LOCK_SH);
2165 	if (unlockerr && err == NULL)
2166 		err = unlockerr;
2167 	return err;
2168 }
2169 
2170 struct diff_dir_cb_arg {
2171     struct got_fileindex *fileindex;
2172     struct got_worktree *worktree;
2173     const char *status_path;
2174     size_t status_path_len;
2175     struct got_repository *repo;
2176     got_worktree_status_cb status_cb;
2177     void *status_arg;
2178     got_worktree_cancel_cb cancel_cb;
2179     void *cancel_arg;
2180 };
2181 
2182 static unsigned char
2183 get_staged_status(struct got_fileindex_entry *ie)
2184 {
2185 	switch (got_fileindex_entry_stage_get(ie)) {
2186 	case GOT_FILEIDX_STAGE_ADD:
2187 		return GOT_STATUS_ADD;
2188 	case GOT_FILEIDX_STAGE_DELETE:
2189 		return GOT_STATUS_DELETE;
2190 	case GOT_FILEIDX_STAGE_MODIFY:
2191 		return GOT_STATUS_MODIFY;
2192 	default:
2193 		return GOT_STATUS_NO_CHANGE;
2194 	}
2195 }
2196 
2197 static const struct got_error *
2198 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
2199     got_worktree_status_cb status_cb, void *status_arg,
2200     struct got_repository *repo)
2201 {
2202 	const struct got_error *err = NULL;
2203 	unsigned char status = GOT_STATUS_NO_CHANGE;
2204 	struct stat sb;
2205 	struct got_object_id blob_id, commit_id;
2206 
2207 	err = get_file_status(&status, &sb, ie, abspath, repo);
2208 	if (err == NULL && status != GOT_STATUS_NO_CHANGE) {
2209 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2210 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2211 		err = (*status_cb)(status_arg, status, get_staged_status(ie),
2212 		    ie->path, &blob_id, &commit_id);
2213 	}
2214 	return err;
2215 }
2216 
2217 static const struct got_error *
2218 status_old_new(void *arg, struct got_fileindex_entry *ie,
2219     struct dirent *de, const char *parent_path)
2220 {
2221 	const struct got_error *err = NULL;
2222 	struct diff_dir_cb_arg *a = arg;
2223 	char *abspath;
2224 
2225 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2226 		return got_error(GOT_ERR_CANCELLED);
2227 
2228 	if (got_path_cmp(parent_path, a->status_path,
2229 	    strlen(parent_path), a->status_path_len) != 0 &&
2230 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
2231 		return NULL;
2232 
2233 	if (parent_path[0]) {
2234 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
2235 		    parent_path, de->d_name) == -1)
2236 			return got_error_from_errno("asprintf");
2237 	} else {
2238 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
2239 		    de->d_name) == -1)
2240 			return got_error_from_errno("asprintf");
2241 	}
2242 
2243 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
2244 	    a->repo);
2245 	free(abspath);
2246 	return err;
2247 }
2248 
2249 static const struct got_error *
2250 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2251 {
2252 	struct diff_dir_cb_arg *a = arg;
2253 	struct got_object_id blob_id, commit_id;
2254 	unsigned char status;
2255 
2256 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2257 		return got_error(GOT_ERR_CANCELLED);
2258 
2259 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
2260 		return NULL;
2261 
2262 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2263 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2264 	if (got_fileindex_entry_has_file_on_disk(ie))
2265 		status = GOT_STATUS_MISSING;
2266 	else
2267 		status = GOT_STATUS_DELETE;
2268 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
2269 	    ie->path, &blob_id, &commit_id);
2270 }
2271 
2272 static const struct got_error *
2273 status_new(void *arg, struct dirent *de, const char *parent_path)
2274 {
2275 	const struct got_error *err = NULL;
2276 	struct diff_dir_cb_arg *a = arg;
2277 	char *path = NULL;
2278 
2279 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2280 		return got_error(GOT_ERR_CANCELLED);
2281 
2282 	if (de->d_type == DT_DIR)
2283 		return NULL;
2284 
2285 	/* XXX ignore symlinks for now */
2286 	if (de->d_type == DT_LNK)
2287 		return NULL;
2288 
2289 	if (parent_path[0]) {
2290 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
2291 			return got_error_from_errno("asprintf");
2292 	} else {
2293 		path = de->d_name;
2294 	}
2295 
2296 	if (got_path_is_child(path, a->status_path, a->status_path_len))
2297 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
2298 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL);
2299 	if (parent_path[0])
2300 		free(path);
2301 	return err;
2302 }
2303 
2304 static const struct got_error *
2305 report_single_file_status(const char *path, const char *ondisk_path,
2306 struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
2307 void *status_arg, struct got_repository *repo)
2308 {
2309 	struct got_fileindex_entry *ie;
2310 	struct stat sb;
2311 
2312 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
2313 	if (ie)
2314 		return report_file_status(ie, ondisk_path, status_cb,
2315 		    status_arg, repo);
2316 
2317 	if (lstat(ondisk_path, &sb) == -1) {
2318 		if (errno != ENOENT)
2319 			return got_error_from_errno2("lstat", ondisk_path);
2320 		return NULL;
2321 	}
2322 
2323 	if (S_ISREG(sb.st_mode))
2324 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
2325 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL);
2326 
2327 	return NULL;
2328 }
2329 
2330 static const struct got_error *
2331 worktree_status(struct got_worktree *worktree, const char *path,
2332     struct got_fileindex *fileindex, struct got_repository *repo,
2333     got_worktree_status_cb status_cb, void *status_arg,
2334     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2335 {
2336 	const struct got_error *err = NULL;
2337 	DIR *workdir = NULL;
2338 	struct got_fileindex_diff_dir_cb fdiff_cb;
2339 	struct diff_dir_cb_arg arg;
2340 	char *ondisk_path = NULL;
2341 
2342 	if (asprintf(&ondisk_path, "%s%s%s",
2343 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
2344 		return got_error_from_errno("asprintf");
2345 
2346 	workdir = opendir(ondisk_path);
2347 	if (workdir == NULL) {
2348 		if (errno != ENOTDIR && errno != ENOENT)
2349 			err = got_error_from_errno2("opendir", ondisk_path);
2350 		else
2351 			err = report_single_file_status(path, ondisk_path,
2352 			    fileindex, status_cb, status_arg, repo);
2353 	} else {
2354 		fdiff_cb.diff_old_new = status_old_new;
2355 		fdiff_cb.diff_old = status_old;
2356 		fdiff_cb.diff_new = status_new;
2357 		arg.fileindex = fileindex;
2358 		arg.worktree = worktree;
2359 		arg.status_path = path;
2360 		arg.status_path_len = strlen(path);
2361 		arg.repo = repo;
2362 		arg.status_cb = status_cb;
2363 		arg.status_arg = status_arg;
2364 		arg.cancel_cb = cancel_cb;
2365 		arg.cancel_arg = cancel_arg;
2366 		err = got_fileindex_diff_dir(fileindex, workdir,
2367 		    worktree->root_path, path, repo, &fdiff_cb, &arg);
2368 	}
2369 
2370 	if (workdir)
2371 		closedir(workdir);
2372 	free(ondisk_path);
2373 	return err;
2374 }
2375 
2376 const struct got_error *
2377 got_worktree_status(struct got_worktree *worktree,
2378     struct got_pathlist_head *paths, struct got_repository *repo,
2379     got_worktree_status_cb status_cb, void *status_arg,
2380     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2381 {
2382 	const struct got_error *err = NULL;
2383 	char *fileindex_path = NULL;
2384 	struct got_fileindex *fileindex = NULL;
2385 	struct got_pathlist_entry *pe;
2386 
2387 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2388 	if (err)
2389 		return err;
2390 
2391 	TAILQ_FOREACH(pe, paths, entry) {
2392 		err = worktree_status(worktree, pe->path, fileindex, repo,
2393 			status_cb, status_arg, cancel_cb, cancel_arg);
2394 		if (err)
2395 			break;
2396 	}
2397 	free(fileindex_path);
2398 	got_fileindex_free(fileindex);
2399 	return err;
2400 }
2401 
2402 const struct got_error *
2403 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
2404     const char *arg)
2405 {
2406 	const struct got_error *err = NULL;
2407 	char *resolved, *cwd = NULL, *path = NULL;
2408 	size_t len;
2409 
2410 	*wt_path = NULL;
2411 
2412 	resolved = realpath(arg, NULL);
2413 	if (resolved == NULL) {
2414 		if (errno != ENOENT)
2415 			return got_error_from_errno2("realpath", arg);
2416 		cwd = getcwd(NULL, 0);
2417 		if (cwd == NULL)
2418 			return got_error_from_errno("getcwd");
2419 		if (asprintf(&resolved, "%s/%s", cwd, arg) == -1) {
2420 			err = got_error_from_errno("asprintf");
2421 			goto done;
2422 		}
2423 	}
2424 
2425 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
2426 	    strlen(got_worktree_get_root_path(worktree)))) {
2427 		err = got_error(GOT_ERR_BAD_PATH);
2428 		goto done;
2429 	}
2430 
2431 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
2432 		err = got_path_skip_common_ancestor(&path,
2433 		    got_worktree_get_root_path(worktree), resolved);
2434 		if (err)
2435 			goto done;
2436 	} else {
2437 		path = strdup("");
2438 		if (path == NULL) {
2439 			err = got_error_from_errno("strdup");
2440 			goto done;
2441 		}
2442 	}
2443 
2444 	/* XXX status walk can't deal with trailing slash! */
2445 	len = strlen(path);
2446 	while (len > 0 && path[len - 1] == '/') {
2447 		path[len - 1] = '\0';
2448 		len--;
2449 	}
2450 done:
2451 	free(resolved);
2452 	free(cwd);
2453 	if (err == NULL)
2454 		*wt_path = path;
2455 	else
2456 		free(path);
2457 	return err;
2458 }
2459 
2460 static const struct got_error *
2461 schedule_addition(const char *ondisk_path, struct got_fileindex *fileindex,
2462     const char *relpath, got_worktree_status_cb status_cb, void *status_arg,
2463     struct got_repository *repo)
2464 {
2465 	const struct got_error *err = NULL;
2466 	struct got_fileindex_entry *ie;
2467 
2468 	/* Re-adding an existing entry is a no-op. */
2469 	if (got_fileindex_entry_get(fileindex, relpath, strlen(relpath)))
2470 		return NULL;
2471 
2472 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
2473 	if (err)
2474 		return err;
2475 
2476 	err = got_fileindex_entry_add(fileindex, ie);
2477 	if (err) {
2478 		got_fileindex_entry_free(ie);
2479 		return err;
2480 	}
2481 
2482 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2483 }
2484 
2485 const struct got_error *
2486 got_worktree_schedule_add(struct got_worktree *worktree,
2487     struct got_pathlist_head *ondisk_paths,
2488     got_worktree_status_cb status_cb, void *status_arg,
2489     struct got_repository *repo)
2490 {
2491 	struct got_fileindex *fileindex = NULL;
2492 	char *fileindex_path = NULL;
2493 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2494 	struct got_pathlist_entry *pe;
2495 
2496 	err = lock_worktree(worktree, LOCK_EX);
2497 	if (err)
2498 		return err;
2499 
2500 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2501 	if (err)
2502 		goto done;
2503 
2504 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2505 		char *relpath;
2506 		err = got_path_skip_common_ancestor(&relpath,
2507 		    got_worktree_get_root_path(worktree), pe->path);
2508 		if (err)
2509 			break;
2510 		err = schedule_addition(pe->path, fileindex, relpath,
2511 		    status_cb, status_arg, repo);
2512 		free(relpath);
2513 		if (err)
2514 			break;
2515 	}
2516 	sync_err = sync_fileindex(fileindex, fileindex_path);
2517 	if (sync_err && err == NULL)
2518 		err = sync_err;
2519 done:
2520 	free(fileindex_path);
2521 	if (fileindex)
2522 		got_fileindex_free(fileindex);
2523 	unlockerr = lock_worktree(worktree, LOCK_SH);
2524 	if (unlockerr && err == NULL)
2525 		err = unlockerr;
2526 	return err;
2527 }
2528 
2529 static const struct got_error *
2530 schedule_for_deletion(const char *ondisk_path, struct got_fileindex *fileindex,
2531     const char *relpath, int delete_local_mods,
2532     got_worktree_status_cb status_cb, void *status_arg,
2533     struct got_repository *repo)
2534 {
2535 	const struct got_error *err = NULL;
2536 	struct got_fileindex_entry *ie = NULL;
2537 	unsigned char status;
2538 	struct stat sb;
2539 
2540 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2541 	if (ie == NULL)
2542 		return got_error(GOT_ERR_BAD_PATH);
2543 
2544 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2545 	if (err)
2546 		return err;
2547 
2548 	if (status != GOT_STATUS_NO_CHANGE) {
2549 		if (status == GOT_STATUS_DELETE)
2550 			return NULL;
2551 		if (status != GOT_STATUS_MODIFY)
2552 			return got_error(GOT_ERR_FILE_STATUS);
2553 		if (!delete_local_mods)
2554 			return got_error(GOT_ERR_FILE_MODIFIED);
2555 	}
2556 
2557 	if (unlink(ondisk_path) != 0)
2558 		return got_error_from_errno2("unlink", ondisk_path);
2559 
2560 	got_fileindex_entry_mark_deleted_from_disk(ie);
2561 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2562 }
2563 
2564 const struct got_error *
2565 got_worktree_schedule_delete(struct got_worktree *worktree,
2566     struct got_pathlist_head *ondisk_paths, int delete_local_mods,
2567     got_worktree_status_cb status_cb, void *status_arg,
2568     struct got_repository *repo)
2569 {
2570 	struct got_fileindex *fileindex = NULL;
2571 	char *fileindex_path = NULL;
2572 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2573 	struct got_pathlist_entry *pe;
2574 
2575 	err = lock_worktree(worktree, LOCK_EX);
2576 	if (err)
2577 		return err;
2578 
2579 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2580 	if (err)
2581 		goto done;
2582 
2583 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2584 		char *relpath;
2585 		err = got_path_skip_common_ancestor(&relpath,
2586 		    got_worktree_get_root_path(worktree), pe->path);
2587 		if (err)
2588 			break;
2589 		err = schedule_for_deletion(pe->path, fileindex, relpath,
2590 		    delete_local_mods, status_cb, status_arg, repo);
2591 		free(relpath);
2592 		if (err)
2593 			break;
2594 	}
2595 	sync_err = sync_fileindex(fileindex, fileindex_path);
2596 	if (sync_err && err == NULL)
2597 		err = sync_err;
2598 done:
2599 	free(fileindex_path);
2600 	if (fileindex)
2601 		got_fileindex_free(fileindex);
2602 	unlockerr = lock_worktree(worktree, LOCK_SH);
2603 	if (unlockerr && err == NULL)
2604 		err = unlockerr;
2605 	return err;
2606 }
2607 
2608 static const struct got_error *
2609 revert_file(struct got_worktree *worktree, struct got_fileindex *fileindex,
2610     const char *ondisk_path,
2611     got_worktree_checkout_cb progress_cb, void *progress_arg,
2612     struct got_repository *repo)
2613 {
2614 	const struct got_error *err = NULL;
2615 	char *relpath = NULL, *parent_path = NULL;
2616 	struct got_fileindex_entry *ie;
2617 	struct got_tree_object *tree = NULL;
2618 	struct got_object_id *tree_id = NULL;
2619 	const struct got_tree_entry *te;
2620 	char *tree_path = NULL, *te_name;
2621 	struct got_blob_object *blob = NULL;
2622 	unsigned char status;
2623 	struct stat sb;
2624 
2625 	err = got_path_skip_common_ancestor(&relpath,
2626 	    got_worktree_get_root_path(worktree), ondisk_path);
2627 	if (err)
2628 		goto done;
2629 
2630 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2631 	if (ie == NULL) {
2632 		err = got_error(GOT_ERR_BAD_PATH);
2633 		goto done;
2634 	}
2635 
2636 	/* Construct in-repository path of tree which contains this blob. */
2637 	err = got_path_dirname(&parent_path, ie->path);
2638 	if (err) {
2639 		if (err->code != GOT_ERR_BAD_PATH)
2640 			goto done;
2641 		parent_path = strdup("/");
2642 		if (parent_path == NULL) {
2643 			err = got_error_from_errno("strdup");
2644 			goto done;
2645 		}
2646 	}
2647 	if (got_path_is_root_dir(worktree->path_prefix)) {
2648 		tree_path = strdup(parent_path);
2649 		if (tree_path == NULL) {
2650 			err = got_error_from_errno("strdup");
2651 			goto done;
2652 		}
2653 	} else {
2654 		if (got_path_is_root_dir(parent_path)) {
2655 			tree_path = strdup(worktree->path_prefix);
2656 			if (tree_path == NULL) {
2657 				err = got_error_from_errno("strdup");
2658 				goto done;
2659 			}
2660 		} else {
2661 			if (asprintf(&tree_path, "%s/%s",
2662 			    worktree->path_prefix, parent_path) == -1) {
2663 				err = got_error_from_errno("asprintf");
2664 				goto done;
2665 			}
2666 		}
2667 	}
2668 
2669 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2670 	if (err)
2671 		goto done;
2672 	if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
2673 		sb.st_mode = got_fileindex_perms_to_st(ie);
2674 
2675 	err = got_object_id_by_path(&tree_id, repo, worktree->base_commit_id,
2676 	    tree_path);
2677 	if (err) {
2678 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
2679 		    status == GOT_STATUS_ADD))
2680 			goto done;
2681 	} else {
2682 		err = got_object_open_as_tree(&tree, repo, tree_id);
2683 		if (err)
2684 			goto done;
2685 
2686 		te_name = basename(ie->path);
2687 		if (te_name == NULL) {
2688 			err = got_error_from_errno2("basename", ie->path);
2689 			goto done;
2690 		}
2691 
2692 		te = got_object_tree_find_entry(tree, te_name);
2693 		if (te == NULL && status != GOT_STATUS_ADD) {
2694 			err = got_error(GOT_ERR_NO_TREE_ENTRY);
2695 			goto done;
2696 		}
2697 	}
2698 
2699 	switch (status) {
2700 	case GOT_STATUS_ADD:
2701 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, ie->path);
2702 		if (err)
2703 			goto done;
2704 		got_fileindex_entry_remove(fileindex, ie);
2705 		break;
2706 	case GOT_STATUS_DELETE:
2707 	case GOT_STATUS_MODIFY:
2708 	case GOT_STATUS_CONFLICT:
2709 	case GOT_STATUS_MISSING: {
2710 		struct got_object_id id;
2711 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2712 		err = got_object_open_as_blob(&blob, repo, &id, 8192);
2713 		if (err)
2714 			goto done;
2715 		err = install_blob(worktree, ondisk_path, ie->path,
2716 		    te->mode, sb.st_mode, blob, 0, 1, repo, progress_cb,
2717 		    progress_arg);
2718 		if (err)
2719 			goto done;
2720 		if (status == GOT_STATUS_DELETE) {
2721 			err = update_blob_fileindex_entry(worktree,
2722 			    fileindex, ie, ondisk_path, ie->path, blob, 1);
2723 			if (err)
2724 				goto done;
2725 		}
2726 		break;
2727 	}
2728 	default:
2729 			goto done;
2730 	}
2731 done:
2732 	free(relpath);
2733 	free(parent_path);
2734 	free(tree_path);
2735 	if (blob)
2736 		got_object_blob_close(blob);
2737 	if (tree)
2738 		got_object_tree_close(tree);
2739 	free(tree_id);
2740 	return err;
2741 }
2742 
2743 const struct got_error *
2744 got_worktree_revert(struct got_worktree *worktree,
2745     struct got_pathlist_head *ondisk_paths,
2746     got_worktree_checkout_cb progress_cb, void *progress_arg,
2747     struct got_repository *repo)
2748 {
2749 	struct got_fileindex *fileindex = NULL;
2750 	char *fileindex_path = NULL;
2751 	const struct got_error *err = NULL, *unlockerr = NULL;
2752 	const struct got_error *sync_err = NULL;
2753 	struct got_pathlist_entry *pe;
2754 
2755 	err = lock_worktree(worktree, LOCK_EX);
2756 	if (err)
2757 		return err;
2758 
2759 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2760 	if (err)
2761 		goto done;
2762 
2763 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2764 		err = revert_file(worktree, fileindex, pe->path,
2765 		    progress_cb, progress_arg, repo);
2766 		if (err)
2767 			break;
2768 	}
2769 	sync_err = sync_fileindex(fileindex, fileindex_path);
2770 	if (sync_err && err == NULL)
2771 		err = sync_err;
2772 done:
2773 	free(fileindex_path);
2774 	if (fileindex)
2775 		got_fileindex_free(fileindex);
2776 	unlockerr = lock_worktree(worktree, LOCK_SH);
2777 	if (unlockerr && err == NULL)
2778 		err = unlockerr;
2779 	return err;
2780 }
2781 
2782 static void
2783 free_commitable(struct got_commitable *ct)
2784 {
2785 	free(ct->path);
2786 	free(ct->in_repo_path);
2787 	free(ct->ondisk_path);
2788 	free(ct->blob_id);
2789 	free(ct->base_blob_id);
2790 	free(ct->base_commit_id);
2791 	free(ct);
2792 }
2793 
2794 struct collect_commitables_arg {
2795 	struct got_pathlist_head *commitable_paths;
2796 	struct got_repository *repo;
2797 	struct got_worktree *worktree;
2798 };
2799 
2800 static const struct got_error *
2801 collect_commitables(void *arg, unsigned char status,
2802     unsigned char staged_status, const char *relpath,
2803     struct got_object_id *blob_id, struct got_object_id *commit_id)
2804 {
2805 	struct collect_commitables_arg *a = arg;
2806 	const struct got_error *err = NULL;
2807 	struct got_commitable *ct = NULL;
2808 	struct got_pathlist_entry *new = NULL;
2809 	char *parent_path = NULL, *path = NULL;
2810 	struct stat sb;
2811 
2812 	if (status == GOT_STATUS_CONFLICT)
2813 		return got_error(GOT_ERR_COMMIT_CONFLICT);
2814 
2815 	if (status != GOT_STATUS_MODIFY && status != GOT_STATUS_ADD &&
2816 	    status != GOT_STATUS_DELETE)
2817 		return NULL;
2818 
2819 	if (asprintf(&path, "/%s", relpath) == -1) {
2820 		err = got_error_from_errno("asprintf");
2821 		goto done;
2822 	}
2823 	if (strcmp(path, "/") == 0) {
2824 		parent_path = strdup("");
2825 		if (parent_path == NULL)
2826 			return got_error_from_errno("strdup");
2827 	} else {
2828 		err = got_path_dirname(&parent_path, path);
2829 		if (err)
2830 			return err;
2831 	}
2832 
2833 	ct = calloc(1, sizeof(*ct));
2834 	if (ct == NULL) {
2835 		err = got_error_from_errno("calloc");
2836 		goto done;
2837 	}
2838 
2839 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
2840 	    relpath) == -1) {
2841 		err = got_error_from_errno("asprintf");
2842 		goto done;
2843 	}
2844 	if (status == GOT_STATUS_DELETE) {
2845 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
2846 	} else {
2847 		if (lstat(ct->ondisk_path, &sb) != 0) {
2848 			err = got_error_from_errno2("lstat", ct->ondisk_path);
2849 			goto done;
2850 		}
2851 		ct->mode = sb.st_mode;
2852 	}
2853 
2854 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
2855 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
2856 	    relpath) == -1) {
2857 		err = got_error_from_errno("asprintf");
2858 		goto done;
2859 	}
2860 
2861 	ct->status = status;
2862 	ct->blob_id = NULL; /* will be filled in when blob gets created */
2863 	if (ct->status != GOT_STATUS_ADD) {
2864 		ct->base_blob_id = got_object_id_dup(blob_id);
2865 		if (ct->base_blob_id == NULL) {
2866 			err = got_error_from_errno("got_object_id_dup");
2867 			goto done;
2868 		}
2869 		ct->base_commit_id = got_object_id_dup(commit_id);
2870 		if (ct->base_commit_id == NULL) {
2871 			err = got_error_from_errno("got_object_id_dup");
2872 			goto done;
2873 		}
2874 	}
2875 	ct->path = strdup(path);
2876 	if (ct->path == NULL) {
2877 		err = got_error_from_errno("strdup");
2878 		goto done;
2879 	}
2880 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
2881 done:
2882 	if (ct && (err || new == NULL))
2883 		free_commitable(ct);
2884 	free(parent_path);
2885 	free(path);
2886 	return err;
2887 }
2888 
2889 static const struct got_error *write_tree(struct got_object_id **,
2890     struct got_tree_object *, const char *, struct got_pathlist_head *,
2891     got_worktree_status_cb status_cb, void *status_arg,
2892     struct got_repository *);
2893 
2894 static const struct got_error *
2895 write_subtree(struct got_object_id **new_subtree_id,
2896     struct got_tree_entry *te, const char *parent_path,
2897     struct got_pathlist_head *commitable_paths,
2898     got_worktree_status_cb status_cb, void *status_arg,
2899     struct got_repository *repo)
2900 {
2901 	const struct got_error *err = NULL;
2902 	struct got_tree_object *subtree;
2903 	char *subpath;
2904 
2905 	if (asprintf(&subpath, "%s%s%s", parent_path,
2906 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
2907 		return got_error_from_errno("asprintf");
2908 
2909 	err = got_object_open_as_tree(&subtree, repo, te->id);
2910 	if (err)
2911 		return err;
2912 
2913 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
2914 	    status_cb, status_arg, repo);
2915 	got_object_tree_close(subtree);
2916 	free(subpath);
2917 	return err;
2918 }
2919 
2920 static const struct got_error *
2921 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
2922 {
2923 	const struct got_error *err = NULL;
2924 	char *ct_parent_path = NULL;
2925 
2926 	*match = 0;
2927 
2928 	if (strchr(ct->in_repo_path, '/') == NULL) {
2929 		*match = got_path_is_root_dir(path);
2930 		return NULL;
2931 	}
2932 
2933 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
2934 	if (err)
2935 		return err;
2936 	*match = (strcmp(path, ct_parent_path) == 0);
2937 	free(ct_parent_path);
2938 	return err;
2939 }
2940 
2941 static mode_t
2942 get_ct_file_mode(struct got_commitable *ct)
2943 {
2944 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
2945 }
2946 
2947 static const struct got_error *
2948 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
2949     struct got_tree_entry *te, struct got_commitable *ct)
2950 {
2951 	const struct got_error *err = NULL;
2952 
2953 	*new_te = NULL;
2954 
2955 	err = got_object_tree_entry_dup(new_te, te);
2956 	if (err)
2957 		goto done;
2958 
2959 	(*new_te)->mode = get_ct_file_mode(ct);
2960 
2961 	free((*new_te)->id);
2962 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2963 	if ((*new_te)->id == NULL) {
2964 		err = got_error_from_errno("got_object_id_dup");
2965 		goto done;
2966 	}
2967 done:
2968 	if (err && *new_te) {
2969 		got_object_tree_entry_close(*new_te);
2970 		*new_te = NULL;
2971 	}
2972 	return err;
2973 }
2974 
2975 static const struct got_error *
2976 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
2977     struct got_commitable *ct)
2978 {
2979 	const struct got_error *err = NULL;
2980 	char *ct_name;
2981 
2982 	 *new_te = NULL;
2983 
2984 	*new_te = calloc(1, sizeof(**new_te));
2985 	if (*new_te == NULL)
2986 		return got_error_from_errno("calloc");
2987 
2988 	ct_name = basename(ct->path);
2989 	if (ct_name == NULL) {
2990 		err = got_error_from_errno2("basename", ct->path);
2991 		goto done;
2992 	}
2993 	(*new_te)->name = strdup(ct_name);
2994 	if ((*new_te)->name == NULL) {
2995 		err = got_error_from_errno("strdup");
2996 		goto done;
2997 	}
2998 
2999 	(*new_te)->mode = get_ct_file_mode(ct);
3000 
3001 	(*new_te)->id = got_object_id_dup(ct->blob_id);
3002 	if ((*new_te)->id == NULL) {
3003 		err = got_error_from_errno("got_object_id_dup");
3004 		goto done;
3005 	}
3006 done:
3007 	if (err && *new_te) {
3008 		got_object_tree_entry_close(*new_te);
3009 		*new_te = NULL;
3010 	}
3011 	return err;
3012 }
3013 
3014 static const struct got_error *
3015 insert_tree_entry(struct got_tree_entry *new_te,
3016     struct got_pathlist_head *paths)
3017 {
3018 	const struct got_error *err = NULL;
3019 	struct got_pathlist_entry *new_pe;
3020 
3021 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
3022 	if (err)
3023 		return err;
3024 	if (new_pe == NULL)
3025 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
3026 	return NULL;
3027 }
3028 
3029 static const struct got_error *
3030 report_ct_status(struct got_commitable *ct,
3031     got_worktree_status_cb status_cb, void *status_arg)
3032 {
3033 	const char *ct_path = ct->path;
3034 	while (ct_path[0] == '/')
3035 		ct_path++;
3036 	return (*status_cb)(status_arg, ct->status, GOT_STATUS_NO_CHANGE,
3037 	    ct_path, ct->blob_id, NULL);
3038 }
3039 
3040 static const struct got_error *
3041 match_modified_subtree(int *modified, struct got_tree_entry *te,
3042     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
3043 {
3044 	const struct got_error *err = NULL;
3045 	struct got_pathlist_entry *pe;
3046 	char *te_path;
3047 
3048 	*modified = 0;
3049 
3050 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
3051 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
3052 	    te->name) == -1)
3053 		return got_error_from_errno("asprintf");
3054 
3055 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3056 		struct got_commitable *ct = pe->data;
3057 		*modified = got_path_is_child(ct->in_repo_path, te_path,
3058 		    strlen(te_path));
3059 		 if (*modified)
3060 			break;
3061 	}
3062 
3063 	free(te_path);
3064 	return err;
3065 }
3066 
3067 static const struct got_error *
3068 match_deleted_or_modified_ct(struct got_commitable **ctp,
3069     struct got_tree_entry *te, const char *base_tree_path,
3070     struct got_pathlist_head *commitable_paths)
3071 {
3072 	const struct got_error *err = NULL;
3073 	struct got_pathlist_entry *pe;
3074 
3075 	*ctp = NULL;
3076 
3077 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3078 		struct got_commitable *ct = pe->data;
3079 		char *ct_name = NULL;
3080 		int path_matches;
3081 
3082 		if (ct->status != GOT_STATUS_MODIFY &&
3083 		    ct->status != GOT_STATUS_DELETE)
3084 			continue;
3085 
3086 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
3087 			continue;
3088 
3089 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
3090 		 if (err)
3091 			return err;
3092 		if (!path_matches)
3093 			continue;
3094 
3095 		ct_name = basename(pe->path);
3096 		if (ct_name == NULL)
3097 			return got_error_from_errno2("basename", pe->path);
3098 
3099 		if (strcmp(te->name, ct_name) != 0)
3100 			continue;
3101 
3102 		*ctp = ct;
3103 		break;
3104 	}
3105 
3106 	return err;
3107 }
3108 
3109 static const struct got_error *
3110 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
3111     const char *child_path, const char *path_base_tree,
3112     struct got_pathlist_head *commitable_paths,
3113     got_worktree_status_cb status_cb, void *status_arg,
3114     struct got_repository *repo)
3115 {
3116 	const struct got_error *err = NULL;
3117 	struct got_tree_entry *new_te;
3118 	char *subtree_path;
3119 
3120 	*new_tep = NULL;
3121 
3122 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
3123 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
3124 	    child_path) == -1)
3125 		return got_error_from_errno("asprintf");
3126 
3127 	new_te = calloc(1, sizeof(*new_te));
3128 	new_te->mode = S_IFDIR;
3129 	new_te->name = strdup(child_path);
3130 	if (new_te->name == NULL) {
3131 		err = got_error_from_errno("strdup");
3132 		got_object_tree_entry_close(new_te);
3133 		goto done;
3134 	}
3135 	err = write_tree(&new_te->id, NULL, subtree_path,
3136 	    commitable_paths, status_cb, status_arg, repo);
3137 	if (err) {
3138 		got_object_tree_entry_close(new_te);
3139 		goto done;
3140 	}
3141 done:
3142 	free(subtree_path);
3143 	if (err == NULL)
3144 		*new_tep = new_te;
3145 	return err;
3146 }
3147 
3148 static const struct got_error *
3149 write_tree(struct got_object_id **new_tree_id,
3150     struct got_tree_object *base_tree, const char *path_base_tree,
3151     struct got_pathlist_head *commitable_paths,
3152     got_worktree_status_cb status_cb, void *status_arg,
3153     struct got_repository *repo)
3154 {
3155 	const struct got_error *err = NULL;
3156 	const struct got_tree_entries *base_entries = NULL;
3157 	struct got_pathlist_head paths;
3158 	struct got_tree_entries new_tree_entries;
3159 	struct got_tree_entry *te, *new_te = NULL;
3160 	struct got_pathlist_entry *pe;
3161 
3162 	TAILQ_INIT(&paths);
3163 	new_tree_entries.nentries = 0;
3164 	SIMPLEQ_INIT(&new_tree_entries.head);
3165 
3166 	/* Insert, and recurse into, newly added entries first. */
3167 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3168 		struct got_commitable *ct = pe->data;
3169 		char *child_path = NULL, *slash;
3170 
3171 		if (ct->status != GOT_STATUS_ADD ||
3172 		    (ct->flags & GOT_COMMITABLE_ADDED))
3173 			continue;
3174 
3175 		 if (!got_path_is_child(pe->path, path_base_tree,
3176 		     strlen(path_base_tree)))
3177 			continue;
3178 
3179 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
3180 		    pe->path);
3181 		if (err)
3182 			goto done;
3183 
3184 		slash = strchr(child_path, '/');
3185 		if (slash == NULL) {
3186 			err = alloc_added_blob_tree_entry(&new_te, ct);
3187 			if (err)
3188 				goto done;
3189 			err = report_ct_status(ct, status_cb, status_arg);
3190 			if (err)
3191 				goto done;
3192 			ct->flags |= GOT_COMMITABLE_ADDED;
3193 			err = insert_tree_entry(new_te, &paths);
3194 			if (err)
3195 				goto done;
3196 		} else {
3197 			*slash = '\0'; /* trim trailing path components */
3198 			if (base_tree == NULL ||
3199 			    got_object_tree_find_entry(base_tree, child_path)
3200 			    == NULL) {
3201 				err = make_subtree_for_added_blob(&new_te,
3202 				    child_path, path_base_tree,
3203 				    commitable_paths, status_cb, status_arg,
3204 				    repo);
3205 				if (err)
3206 					goto done;
3207 				err = insert_tree_entry(new_te, &paths);
3208 				if (err)
3209 					goto done;
3210 			}
3211 		}
3212 	}
3213 
3214 	if (base_tree) {
3215 		/* Handle modified and deleted entries. */
3216 		base_entries = got_object_tree_get_entries(base_tree);
3217 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
3218 			struct got_commitable *ct = NULL;
3219 
3220 			if (S_ISDIR(te->mode)) {
3221 				int modified;
3222 				err = got_object_tree_entry_dup(&new_te, te);
3223 				if (err)
3224 					goto done;
3225 				err = match_modified_subtree(&modified, te,
3226 				    path_base_tree, commitable_paths);
3227 				if (err)
3228 					goto done;
3229 				/* Avoid recursion into unmodified subtrees. */
3230 				if (modified) {
3231 					free(new_te->id);
3232 					err = write_subtree(&new_te->id, te,
3233 					    path_base_tree, commitable_paths,
3234 					    status_cb, status_arg, repo);
3235 					if (err)
3236 						goto done;
3237 				}
3238 				err = insert_tree_entry(new_te, &paths);
3239 				if (err)
3240 					goto done;
3241 				continue;
3242 			}
3243 
3244 			err = match_deleted_or_modified_ct(&ct, te,
3245 			    path_base_tree, commitable_paths);
3246 			if (ct) {
3247 				/* NB: Deleted entries get dropped here. */
3248 				if (ct->status == GOT_STATUS_MODIFY) {
3249 					err = alloc_modified_blob_tree_entry(
3250 					    &new_te, te, ct);
3251 					if (err)
3252 						goto done;
3253 					err = insert_tree_entry(new_te, &paths);
3254 					if (err)
3255 						goto done;
3256 				}
3257 				err = report_ct_status(ct, status_cb,
3258 				    status_arg);
3259 				if (err)
3260 					goto done;
3261 			} else {
3262 				/* Entry is unchanged; just copy it. */
3263 				err = got_object_tree_entry_dup(&new_te, te);
3264 				if (err)
3265 					goto done;
3266 				err = insert_tree_entry(new_te, &paths);
3267 				if (err)
3268 					goto done;
3269 			}
3270 		}
3271 	}
3272 
3273 	/* Write new list of entries; deleted entries have been dropped. */
3274 	TAILQ_FOREACH(pe, &paths, entry) {
3275 		struct got_tree_entry *te = pe->data;
3276 		new_tree_entries.nentries++;
3277 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
3278 	}
3279 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
3280 done:
3281 	got_object_tree_entries_close(&new_tree_entries);
3282 	got_pathlist_free(&paths);
3283 	return err;
3284 }
3285 
3286 static const struct got_error *
3287 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
3288     struct got_object_id *new_base_commit_id, struct got_fileindex *fileindex)
3289 {
3290 	const struct got_error *err = NULL;
3291 	struct got_pathlist_entry *pe;
3292 
3293 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3294 		struct got_fileindex_entry *ie;
3295 		struct got_commitable *ct = pe->data;
3296 
3297 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
3298 		if (ie) {
3299 			if (ct->status == GOT_STATUS_DELETE) {
3300 				got_fileindex_entry_remove(fileindex, ie);
3301 				got_fileindex_entry_free(ie);
3302 			} else
3303 				err = got_fileindex_entry_update(ie,
3304 				    ct->ondisk_path, ct->blob_id->sha1,
3305 				    new_base_commit_id->sha1, 1);
3306 		} else {
3307 			err = got_fileindex_entry_alloc(&ie,
3308 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
3309 			    new_base_commit_id->sha1);
3310 			if (err)
3311 				break;
3312 			err = got_fileindex_entry_add(fileindex, ie);
3313 			if (err)
3314 				break;
3315 		}
3316 	}
3317 	return err;
3318 }
3319 
3320 static const struct got_error *
3321 check_ct_out_of_date(struct got_commitable *ct, struct got_repository *repo,
3322 	struct got_object_id *head_commit_id)
3323 {
3324 	const struct got_error *err = NULL;
3325 	struct got_object_id *id = NULL;
3326 	struct got_commit_object *commit = NULL;
3327 	const char *ct_path = ct->in_repo_path;
3328 
3329 	while (ct_path[0] == '/')
3330 		ct_path++;
3331 
3332 	if (ct->status != GOT_STATUS_ADD) {
3333 		/* Trivial case: base commit == head commit */
3334 		if (got_object_id_cmp(ct->base_commit_id, head_commit_id) == 0)
3335 			return NULL;
3336 		/*
3337 		 * Ensure file content which local changes were based
3338 		 * on matches file content in the branch head.
3339 		 */
3340 		err = got_object_id_by_path(&id, repo, head_commit_id, ct_path);
3341 		if (err) {
3342 			if (err->code != GOT_ERR_NO_TREE_ENTRY)
3343 				goto done;
3344 			err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3345 			goto done;
3346 		} else if (got_object_id_cmp(id, ct->base_blob_id) != 0)
3347 			err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3348 	} else {
3349 		/* Require that added files don't exist in the branch head. */
3350 		err = got_object_id_by_path(&id, repo, head_commit_id, ct_path);
3351 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3352 			goto done;
3353 		err = id ? got_error(GOT_ERR_COMMIT_OUT_OF_DATE) : NULL;
3354 	}
3355 done:
3356 	if (commit)
3357 		got_object_commit_close(commit);
3358 	free(id);
3359 	return err;
3360 }
3361 
3362 const struct got_error *
3363 commit_worktree(struct got_object_id **new_commit_id,
3364     struct got_pathlist_head *commitable_paths,
3365     struct got_object_id *head_commit_id, struct got_worktree *worktree,
3366     const char *author, const char *committer,
3367     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3368     got_worktree_status_cb status_cb, void *status_arg,
3369     struct got_repository *repo)
3370 {
3371 	const struct got_error *err = NULL, *unlockerr = NULL;
3372 	struct got_pathlist_entry *pe;
3373 	const char *head_ref_name = NULL;
3374 	struct got_commit_object *head_commit = NULL;
3375 	struct got_reference *head_ref2 = NULL;
3376 	struct got_object_id *head_commit_id2 = NULL;
3377 	struct got_tree_object *head_tree = NULL;
3378 	struct got_object_id *new_tree_id = NULL;
3379 	struct got_object_id_queue parent_ids;
3380 	struct got_object_qid *pid = NULL;
3381 	char *logmsg = NULL;
3382 
3383 	*new_commit_id = NULL;
3384 
3385 	SIMPLEQ_INIT(&parent_ids);
3386 
3387 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
3388 	if (err)
3389 		goto done;
3390 
3391 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
3392 	if (err)
3393 		goto done;
3394 
3395 	if (commit_msg_cb != NULL) {
3396 		err = commit_msg_cb(commitable_paths, &logmsg, commit_arg);
3397 		if (err)
3398 			goto done;
3399 	}
3400 
3401 	if (logmsg == NULL || strlen(logmsg) == 0) {
3402 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
3403 		goto done;
3404 	}
3405 
3406 	/* Create blobs from added and modified files and record their IDs. */
3407 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3408 		struct got_commitable *ct = pe->data;
3409 		char *ondisk_path;
3410 
3411 		if (ct->status != GOT_STATUS_ADD &&
3412 		    ct->status != GOT_STATUS_MODIFY)
3413 			continue;
3414 
3415 		if (asprintf(&ondisk_path, "%s/%s",
3416 		    worktree->root_path, pe->path) == -1) {
3417 			err = got_error_from_errno("asprintf");
3418 			goto done;
3419 		}
3420 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
3421 		free(ondisk_path);
3422 		if (err)
3423 			goto done;
3424 	}
3425 
3426 	/* Recursively write new tree objects. */
3427 	err = write_tree(&new_tree_id, head_tree, "/", commitable_paths,
3428 	    status_cb, status_arg, repo);
3429 	if (err)
3430 		goto done;
3431 
3432 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
3433 	if (err)
3434 		goto done;
3435 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
3436 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
3437 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
3438 	got_object_qid_free(pid);
3439 	if (logmsg != NULL)
3440 		free(logmsg);
3441 	if (err)
3442 		goto done;
3443 
3444 	/* Check if a concurrent commit to our branch has occurred. */
3445 	head_ref_name = got_worktree_get_head_ref_name(worktree);
3446 	if (head_ref_name == NULL) {
3447 		err = got_error_from_errno("got_worktree_get_head_ref_name");
3448 		goto done;
3449 	}
3450 	/* Lock the reference here to prevent concurrent modification. */
3451 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
3452 	if (err)
3453 		goto done;
3454 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
3455 	if (err)
3456 		goto done;
3457 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
3458 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
3459 		goto done;
3460 	}
3461 	/* Update branch head in repository. */
3462 	err = got_ref_change_ref(head_ref2, *new_commit_id);
3463 	if (err)
3464 		goto done;
3465 	err = got_ref_write(head_ref2, repo);
3466 	if (err)
3467 		goto done;
3468 
3469 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
3470 	if (err)
3471 		goto done;
3472 
3473 	err = ref_base_commit(worktree, repo);
3474 	if (err)
3475 		goto done;
3476 done:
3477 	if (head_tree)
3478 		got_object_tree_close(head_tree);
3479 	if (head_commit)
3480 		got_object_commit_close(head_commit);
3481 	free(head_commit_id2);
3482 	if (head_ref2) {
3483 		unlockerr = got_ref_unlock(head_ref2);
3484 		if (unlockerr && err == NULL)
3485 			err = unlockerr;
3486 		got_ref_close(head_ref2);
3487 	}
3488 	return err;
3489 }
3490 
3491 static const struct got_error *
3492 check_path_is_commitable(const char *path,
3493     struct got_pathlist_head *commitable_paths)
3494 {
3495 	struct got_pathlist_entry *cpe = NULL;
3496 	size_t path_len = strlen(path);
3497 
3498 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
3499 		struct got_commitable *ct = cpe->data;
3500 		const char *ct_path = ct->path;
3501 
3502 		while (ct_path[0] == '/')
3503 			ct_path++;
3504 
3505 		if (strcmp(path, ct_path) == 0 ||
3506 		    got_path_is_child(ct_path, path, path_len))
3507 			break;
3508 	}
3509 
3510 	if (cpe == NULL)
3511 		return got_error_path(path, GOT_ERR_BAD_PATH);
3512 
3513 	return NULL;
3514 }
3515 
3516 const struct got_error *
3517 got_worktree_commit(struct got_object_id **new_commit_id,
3518     struct got_worktree *worktree, struct got_pathlist_head *paths,
3519     const char *author, const char *committer,
3520     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3521     got_worktree_status_cb status_cb, void *status_arg,
3522     struct got_repository *repo)
3523 {
3524 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
3525 	struct got_fileindex *fileindex = NULL;
3526 	char *fileindex_path = NULL;
3527 	struct got_pathlist_head commitable_paths;
3528 	struct collect_commitables_arg cc_arg;
3529 	struct got_pathlist_entry *pe;
3530 	struct got_reference *head_ref = NULL;
3531 	struct got_object_id *head_commit_id = NULL;
3532 
3533 	*new_commit_id = NULL;
3534 
3535 	TAILQ_INIT(&commitable_paths);
3536 
3537 	err = lock_worktree(worktree, LOCK_EX);
3538 	if (err)
3539 		goto done;
3540 
3541 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
3542 	if (err)
3543 		goto done;
3544 
3545 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
3546 	if (err)
3547 		goto done;
3548 
3549 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3550 	if (err)
3551 		goto done;
3552 
3553 	cc_arg.commitable_paths = &commitable_paths;
3554 	cc_arg.worktree = worktree;
3555 	cc_arg.repo = repo;
3556 	TAILQ_FOREACH(pe, paths, entry) {
3557 		err = worktree_status(worktree, pe->path, fileindex, repo,
3558 		    collect_commitables, &cc_arg, NULL, NULL);
3559 		if (err)
3560 			goto done;
3561 	}
3562 
3563 	if (TAILQ_EMPTY(&commitable_paths)) {
3564 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
3565 		goto done;
3566 	}
3567 
3568 	TAILQ_FOREACH(pe, paths, entry) {
3569 		err = check_path_is_commitable(pe->path, &commitable_paths);
3570 		if (err)
3571 			goto done;
3572 	}
3573 
3574 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3575 		struct got_commitable *ct = pe->data;
3576 		err = check_ct_out_of_date(ct, repo, head_commit_id);
3577 		if (err)
3578 			goto done;
3579 	}
3580 
3581 	err = commit_worktree(new_commit_id, &commitable_paths,
3582 	    head_commit_id, worktree, author, committer,
3583 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
3584 	if (err)
3585 		goto done;
3586 
3587 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
3588 	    fileindex);
3589 	sync_err = sync_fileindex(fileindex, fileindex_path);
3590 	if (sync_err && err == NULL)
3591 		err = sync_err;
3592 done:
3593 	if (fileindex)
3594 		got_fileindex_free(fileindex);
3595 	free(fileindex_path);
3596 	unlockerr = lock_worktree(worktree, LOCK_SH);
3597 	if (unlockerr && err == NULL)
3598 		err = unlockerr;
3599 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3600 		struct got_commitable *ct = pe->data;
3601 		free_commitable(ct);
3602 	}
3603 	got_pathlist_free(&commitable_paths);
3604 	return err;
3605 }
3606 
3607 const char *
3608 got_commitable_get_path(struct got_commitable *ct)
3609 {
3610 	return ct->path;
3611 }
3612 
3613 unsigned int
3614 got_commitable_get_status(struct got_commitable *ct)
3615 {
3616 	return ct->status;
3617 }
3618 
3619 struct check_rebase_ok_arg {
3620 	struct got_worktree *worktree;
3621 	struct got_repository *repo;
3622 };
3623 
3624 static const struct got_error *
3625 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
3626 {
3627 	const struct got_error *err = NULL;
3628 	struct check_rebase_ok_arg *a = arg;
3629 	unsigned char status;
3630 	struct stat sb;
3631 	char *ondisk_path;
3632 
3633 	/* Reject rebase of a work tree with mixed base commits. */
3634 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
3635 	    SHA1_DIGEST_LENGTH))
3636 		return got_error(GOT_ERR_MIXED_COMMITS);
3637 
3638 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3639 	    == -1)
3640 		return got_error_from_errno("asprintf");
3641 
3642 	/* Reject rebase of a work tree with modified or conflicted files. */
3643 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
3644 	free(ondisk_path);
3645 	if (err)
3646 		return err;
3647 
3648 	if (status != GOT_STATUS_NO_CHANGE)
3649 		return got_error(GOT_ERR_MODIFIED);
3650 
3651 	return NULL;
3652 }
3653 
3654 const struct got_error *
3655 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
3656     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
3657     struct got_worktree *worktree, struct got_reference *branch,
3658     struct got_repository *repo)
3659 {
3660 	const struct got_error *err = NULL;
3661 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
3662 	char *branch_ref_name = NULL;
3663 	char *fileindex_path = NULL;
3664 	struct check_rebase_ok_arg ok_arg;
3665 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
3666 
3667 	*new_base_branch_ref = NULL;
3668 	*tmp_branch = NULL;
3669 	*fileindex = NULL;
3670 
3671 	err = lock_worktree(worktree, LOCK_EX);
3672 	if (err)
3673 		return err;
3674 
3675 	err = open_fileindex(fileindex, &fileindex_path, worktree);
3676 	if (err)
3677 		goto done;
3678 
3679 	ok_arg.worktree = worktree;
3680 	ok_arg.repo = repo;
3681 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
3682 	    &ok_arg);
3683 	if (err)
3684 		goto done;
3685 
3686 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3687 	if (err)
3688 		goto done;
3689 
3690 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3691 	if (err)
3692 		goto done;
3693 
3694 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3695 	if (err)
3696 		goto done;
3697 
3698 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
3699 	    0);
3700 	if (err)
3701 		goto done;
3702 
3703 	err = got_ref_alloc_symref(new_base_branch_ref,
3704 	    new_base_branch_ref_name, wt_branch);
3705 	if (err)
3706 		goto done;
3707 	err = got_ref_write(*new_base_branch_ref, repo);
3708 	if (err)
3709 		goto done;
3710 
3711 	/* TODO Lock original branch's ref while rebasing? */
3712 
3713 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
3714 	if (err)
3715 		goto done;
3716 
3717 	err = got_ref_write(branch_ref, repo);
3718 	if (err)
3719 		goto done;
3720 
3721 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
3722 	    worktree->base_commit_id);
3723 	if (err)
3724 		goto done;
3725 	err = got_ref_write(*tmp_branch, repo);
3726 	if (err)
3727 		goto done;
3728 
3729 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
3730 	if (err)
3731 		goto done;
3732 done:
3733 	free(fileindex_path);
3734 	free(tmp_branch_name);
3735 	free(new_base_branch_ref_name);
3736 	free(branch_ref_name);
3737 	if (branch_ref)
3738 		got_ref_close(branch_ref);
3739 	if (wt_branch)
3740 		got_ref_close(wt_branch);
3741 	if (err) {
3742 		if (*new_base_branch_ref) {
3743 			got_ref_close(*new_base_branch_ref);
3744 			*new_base_branch_ref = NULL;
3745 		}
3746 		if (*tmp_branch) {
3747 			got_ref_close(*tmp_branch);
3748 			*tmp_branch = NULL;
3749 		}
3750 		if (*fileindex) {
3751 			got_fileindex_free(*fileindex);
3752 			*fileindex = NULL;
3753 		}
3754 		lock_worktree(worktree, LOCK_SH);
3755 	}
3756 	return err;
3757 }
3758 
3759 const struct got_error *
3760 got_worktree_rebase_continue(struct got_object_id **commit_id,
3761     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
3762     struct got_reference **branch, struct got_fileindex **fileindex,
3763     struct got_worktree *worktree, struct got_repository *repo)
3764 {
3765 	const struct got_error *err;
3766 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
3767 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
3768 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
3769 	char *fileindex_path = NULL;
3770 
3771 	*commit_id = NULL;
3772 	*new_base_branch = NULL;
3773 	*tmp_branch = NULL;
3774 	*branch = NULL;
3775 	*fileindex = NULL;
3776 
3777 	err = lock_worktree(worktree, LOCK_EX);
3778 	if (err)
3779 		return err;
3780 
3781 	err = open_fileindex(fileindex, &fileindex_path, worktree);
3782 	if (err)
3783 		goto done;
3784 
3785 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3786 	if (err)
3787 		return err;
3788 
3789 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3790 	if (err)
3791 		goto done;
3792 
3793 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
3794 	if (err)
3795 		goto done;
3796 
3797 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3798 	if (err)
3799 		goto done;
3800 
3801 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
3802 	if (err)
3803 		goto done;
3804 
3805 	err = got_ref_open(branch, repo,
3806 	    got_ref_get_symref_target(branch_ref), 0);
3807 	if (err)
3808 		goto done;
3809 
3810 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3811 	if (err)
3812 		goto done;
3813 
3814 	err = got_ref_resolve(commit_id, repo, commit_ref);
3815 	if (err)
3816 		goto done;
3817 
3818 	err = got_ref_open(new_base_branch, repo,
3819 	    new_base_branch_ref_name, 0);
3820 	if (err)
3821 		goto done;
3822 
3823 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
3824 	if (err)
3825 		goto done;
3826 done:
3827 	free(commit_ref_name);
3828 	free(branch_ref_name);
3829 	free(fileindex_path);
3830 	if (commit_ref)
3831 		got_ref_close(commit_ref);
3832 	if (branch_ref)
3833 		got_ref_close(branch_ref);
3834 	if (err) {
3835 		free(*commit_id);
3836 		*commit_id = NULL;
3837 		if (*tmp_branch) {
3838 			got_ref_close(*tmp_branch);
3839 			*tmp_branch = NULL;
3840 		}
3841 		if (*new_base_branch) {
3842 			got_ref_close(*new_base_branch);
3843 			*new_base_branch = NULL;
3844 		}
3845 		if (*branch) {
3846 			got_ref_close(*branch);
3847 			*branch = NULL;
3848 		}
3849 		if (*fileindex) {
3850 			got_fileindex_free(*fileindex);
3851 			*fileindex = NULL;
3852 		}
3853 		lock_worktree(worktree, LOCK_SH);
3854 	}
3855 	return err;
3856 }
3857 
3858 const struct got_error *
3859 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
3860 {
3861 	const struct got_error *err;
3862 	char *tmp_branch_name = NULL;
3863 
3864 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3865 	if (err)
3866 		return err;
3867 
3868 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
3869 	free(tmp_branch_name);
3870 	return NULL;
3871 }
3872 
3873 static const struct got_error *
3874 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
3875     char **logmsg, void *arg)
3876 {
3877 	*logmsg = arg;
3878 	return NULL;
3879 }
3880 
3881 static const struct got_error *
3882 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
3883     const char *path, struct got_object_id *blob_id,
3884     struct got_object_id *commit_id)
3885 {
3886 	return NULL;
3887 }
3888 
3889 struct collect_merged_paths_arg {
3890 	got_worktree_checkout_cb progress_cb;
3891 	void *progress_arg;
3892 	struct got_pathlist_head *merged_paths;
3893 };
3894 
3895 static const struct got_error *
3896 collect_merged_paths(void *arg, unsigned char status, const char *path)
3897 {
3898 	const struct got_error *err;
3899 	struct collect_merged_paths_arg *a = arg;
3900 	char *p;
3901 	struct got_pathlist_entry *new;
3902 
3903 	err = (*a->progress_cb)(a->progress_arg, status, path);
3904 	if (err)
3905 		return err;
3906 
3907 	if (status != GOT_STATUS_MERGE &&
3908 	    status != GOT_STATUS_ADD &&
3909 	    status != GOT_STATUS_DELETE &&
3910 	    status != GOT_STATUS_CONFLICT)
3911 		return NULL;
3912 
3913 	p = strdup(path);
3914 	if (p == NULL)
3915 		return got_error_from_errno("strdup");
3916 
3917 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
3918 	if (err || new == NULL)
3919 		free(p);
3920 	return err;
3921 }
3922 
3923 void
3924 got_worktree_rebase_pathlist_free(struct got_pathlist_head *merged_paths)
3925 {
3926 	struct got_pathlist_entry *pe;
3927 
3928 	TAILQ_FOREACH(pe, merged_paths, entry)
3929 		free((char *)pe->path);
3930 
3931 	got_pathlist_free(merged_paths);
3932 }
3933 
3934 static const struct got_error *
3935 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
3936     struct got_repository *repo)
3937 {
3938 	const struct got_error *err;
3939 	struct got_reference *commit_ref = NULL;
3940 
3941 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3942 	if (err) {
3943 		if (err->code != GOT_ERR_NOT_REF)
3944 			goto done;
3945 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
3946 		if (err)
3947 			goto done;
3948 		err = got_ref_write(commit_ref, repo);
3949 		if (err)
3950 			goto done;
3951 	} else {
3952 		struct got_object_id *stored_id;
3953 		int cmp;
3954 
3955 		err = got_ref_resolve(&stored_id, repo, commit_ref);
3956 		if (err)
3957 			goto done;
3958 		cmp = got_object_id_cmp(commit_id, stored_id);
3959 		free(stored_id);
3960 		if (cmp != 0) {
3961 			err = got_error(GOT_ERR_REBASE_COMMITID);
3962 			goto done;
3963 		}
3964 	}
3965 done:
3966 	if (commit_ref)
3967 		got_ref_close(commit_ref);
3968 	return err;
3969 }
3970 
3971 static const struct got_error *
3972 rebase_merge_files(struct got_pathlist_head *merged_paths,
3973     const char *commit_ref_name, struct got_worktree *worktree,
3974     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
3975     struct got_object_id *commit_id, struct got_repository *repo,
3976     got_worktree_checkout_cb progress_cb, void *progress_arg,
3977     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
3978 {
3979 	const struct got_error *err;
3980 	struct got_reference *commit_ref = NULL;
3981 	struct collect_merged_paths_arg cmp_arg;
3982 	char *fileindex_path;
3983 
3984 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
3985 
3986 	err = get_fileindex_path(&fileindex_path, worktree);
3987 	if (err)
3988 		return err;
3989 
3990 	cmp_arg.progress_cb = progress_cb;
3991 	cmp_arg.progress_arg = progress_arg;
3992 	cmp_arg.merged_paths = merged_paths;
3993 	err = merge_files(worktree, fileindex, fileindex_path,
3994 	    parent_commit_id, commit_id, repo, collect_merged_paths,
3995 	    &cmp_arg, cancel_cb, cancel_arg);
3996 	if (commit_ref)
3997 		got_ref_close(commit_ref);
3998 	return err;
3999 }
4000 
4001 const struct got_error *
4002 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
4003     struct got_worktree *worktree, struct got_fileindex *fileindex,
4004     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4005     struct got_repository *repo,
4006     got_worktree_checkout_cb progress_cb, void *progress_arg,
4007     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
4008 {
4009 	const struct got_error *err;
4010 	char *commit_ref_name;
4011 
4012 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4013 	if (err)
4014 		return err;
4015 
4016 	err = store_commit_id(commit_ref_name, commit_id, repo);
4017 	if (err)
4018 		goto done;
4019 
4020 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4021 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4022 	    progress_arg, cancel_cb, cancel_arg);
4023 done:
4024 	free(commit_ref_name);
4025 	return err;
4026 }
4027 
4028 const struct got_error *
4029 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
4030     struct got_worktree *worktree, struct got_fileindex *fileindex,
4031     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4032     struct got_repository *repo,
4033     got_worktree_checkout_cb progress_cb, void *progress_arg,
4034     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
4035 {
4036 	const struct got_error *err;
4037 	char *commit_ref_name;
4038 
4039 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4040 	if (err)
4041 		return err;
4042 
4043 	err = store_commit_id(commit_ref_name, commit_id, repo);
4044 	if (err)
4045 		goto done;
4046 
4047 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4048 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4049 	    progress_arg, cancel_cb, cancel_arg);
4050 done:
4051 	free(commit_ref_name);
4052 	return err;
4053 }
4054 
4055 static const struct got_error *
4056 rebase_commit(struct got_object_id **new_commit_id,
4057     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
4058     struct got_worktree *worktree, struct got_fileindex *fileindex,
4059     struct got_reference *tmp_branch, struct got_commit_object *orig_commit,
4060     const char *new_logmsg, struct got_repository *repo)
4061 {
4062 	const struct got_error *err, *sync_err;
4063 	struct got_pathlist_head commitable_paths;
4064 	struct collect_commitables_arg cc_arg;
4065 	char *fileindex_path = NULL;
4066 	struct got_reference *head_ref = NULL;
4067 	struct got_object_id *head_commit_id = NULL;
4068 	char *logmsg = NULL;
4069 
4070 	TAILQ_INIT(&commitable_paths);
4071 	*new_commit_id = NULL;
4072 
4073 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
4074 
4075 	err = get_fileindex_path(&fileindex_path, worktree);
4076 	if (err)
4077 		return err;
4078 
4079 	cc_arg.commitable_paths = &commitable_paths;
4080 	cc_arg.worktree = worktree;
4081 	cc_arg.repo = repo;
4082 	/*
4083 	 * If possible get the status of individual files directly to
4084 	 * avoid crawling the entire work tree once per rebased commit.
4085 	 * TODO: Ideally, merged_paths would contain a list of commitables
4086 	 * we could use so we could skip worktree_status() entirely.
4087 	 */
4088 	if (merged_paths) {
4089 		struct got_pathlist_entry *pe;
4090 		if (TAILQ_EMPTY(merged_paths)) {
4091 			err = got_error(GOT_ERR_NO_MERGED_PATHS);
4092 			goto done;
4093 		}
4094 		TAILQ_FOREACH(pe, merged_paths, entry) {
4095 			err = worktree_status(worktree, pe->path, fileindex,
4096 			    repo, collect_commitables, &cc_arg, NULL, NULL);
4097 			if (err)
4098 				goto done;
4099 		}
4100 	} else {
4101 		err = worktree_status(worktree, "", fileindex, repo,
4102 		    collect_commitables, &cc_arg, NULL, NULL);
4103 		if (err)
4104 			goto done;
4105 	}
4106 
4107 	if (TAILQ_EMPTY(&commitable_paths)) {
4108 		/* No-op change; commit will be elided. */
4109 		err = got_ref_delete(commit_ref, repo);
4110 		if (err)
4111 			goto done;
4112 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
4113 		goto done;
4114 	}
4115 
4116 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
4117 	if (err)
4118 		goto done;
4119 
4120 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
4121 	if (err)
4122 		goto done;
4123 
4124 	if (new_logmsg)
4125 		logmsg = strdup(new_logmsg);
4126 	else
4127 		logmsg = strdup(got_object_commit_get_logmsg(orig_commit));
4128 	if (logmsg == NULL)
4129 		return got_error_from_errno("strdup");
4130 
4131 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
4132 	    worktree, got_object_commit_get_author(orig_commit),
4133 	    got_object_commit_get_committer(orig_commit),
4134 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
4135 	if (err)
4136 		goto done;
4137 
4138 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
4139 	if (err)
4140 		goto done;
4141 
4142 	err = got_ref_delete(commit_ref, repo);
4143 	if (err)
4144 		goto done;
4145 
4146 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
4147 	    fileindex);
4148 	sync_err = sync_fileindex(fileindex, fileindex_path);
4149 	if (sync_err && err == NULL)
4150 		err = sync_err;
4151 done:
4152 	free(fileindex_path);
4153 	free(head_commit_id);
4154 	if (head_ref)
4155 		got_ref_close(head_ref);
4156 	if (err) {
4157 		free(*new_commit_id);
4158 		*new_commit_id = NULL;
4159 	}
4160 	return err;
4161 }
4162 
4163 const struct got_error *
4164 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
4165     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4166     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4167     struct got_commit_object *orig_commit,
4168     struct got_object_id *orig_commit_id, struct got_repository *repo)
4169 {
4170 	const struct got_error *err;
4171 	char *commit_ref_name;
4172 	struct got_reference *commit_ref = NULL;
4173 	struct got_object_id *commit_id = NULL;
4174 
4175 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4176 	if (err)
4177 		return err;
4178 
4179 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4180 	if (err)
4181 		goto done;
4182 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4183 	if (err)
4184 		goto done;
4185 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4186 		err = got_error(GOT_ERR_REBASE_COMMITID);
4187 		goto done;
4188 	}
4189 
4190 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4191 	    worktree, fileindex, tmp_branch, orig_commit, NULL, repo);
4192 done:
4193 	if (commit_ref)
4194 		got_ref_close(commit_ref);
4195 	free(commit_ref_name);
4196 	free(commit_id);
4197 	return err;
4198 }
4199 
4200 const struct got_error *
4201 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
4202     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4203     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4204     struct got_commit_object *orig_commit,
4205     struct got_object_id *orig_commit_id, const char *new_logmsg,
4206     struct got_repository *repo)
4207 {
4208 	const struct got_error *err;
4209 	char *commit_ref_name;
4210 	struct got_reference *commit_ref = NULL;
4211 	struct got_object_id *commit_id = NULL;
4212 
4213 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4214 	if (err)
4215 		return err;
4216 
4217 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4218 	if (err)
4219 		goto done;
4220 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4221 	if (err)
4222 		goto done;
4223 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4224 		err = got_error(GOT_ERR_HISTEDIT_COMMITID);
4225 		goto done;
4226 	}
4227 
4228 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4229 	    worktree, fileindex, tmp_branch, orig_commit, new_logmsg, repo);
4230 done:
4231 	if (commit_ref)
4232 		got_ref_close(commit_ref);
4233 	free(commit_ref_name);
4234 	free(commit_id);
4235 	return err;
4236 }
4237 
4238 const struct got_error *
4239 got_worktree_rebase_postpone(struct got_worktree *worktree,
4240     struct got_fileindex *fileindex)
4241 {
4242 	if (fileindex)
4243 		got_fileindex_free(fileindex);
4244 	return lock_worktree(worktree, LOCK_SH);
4245 }
4246 
4247 static const struct got_error *
4248 delete_ref(const char *name, struct got_repository *repo)
4249 {
4250 	const struct got_error *err;
4251 	struct got_reference *ref;
4252 
4253 	err = got_ref_open(&ref, repo, name, 0);
4254 	if (err) {
4255 		if (err->code == GOT_ERR_NOT_REF)
4256 			return NULL;
4257 		return err;
4258 	}
4259 
4260 	err = got_ref_delete(ref, repo);
4261 	got_ref_close(ref);
4262 	return err;
4263 }
4264 
4265 static const struct got_error *
4266 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
4267 {
4268 	const struct got_error *err;
4269 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
4270 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
4271 
4272 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4273 	if (err)
4274 		goto done;
4275 	err = delete_ref(tmp_branch_name, repo);
4276 	if (err)
4277 		goto done;
4278 
4279 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
4280 	if (err)
4281 		goto done;
4282 	err = delete_ref(new_base_branch_ref_name, repo);
4283 	if (err)
4284 		goto done;
4285 
4286 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
4287 	if (err)
4288 		goto done;
4289 	err = delete_ref(branch_ref_name, repo);
4290 	if (err)
4291 		goto done;
4292 
4293 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4294 	if (err)
4295 		goto done;
4296 	err = delete_ref(commit_ref_name, repo);
4297 	if (err)
4298 		goto done;
4299 
4300 done:
4301 	free(tmp_branch_name);
4302 	free(new_base_branch_ref_name);
4303 	free(branch_ref_name);
4304 	free(commit_ref_name);
4305 	return err;
4306 }
4307 
4308 const struct got_error *
4309 got_worktree_rebase_complete(struct got_worktree *worktree,
4310     struct got_fileindex *fileindex, struct got_reference *new_base_branch,
4311     struct got_reference *tmp_branch, struct got_reference *rebased_branch,
4312     struct got_repository *repo)
4313 {
4314 	const struct got_error *err, *unlockerr;
4315 	struct got_object_id *new_head_commit_id = NULL;
4316 
4317 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
4318 	if (err)
4319 		return err;
4320 
4321 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
4322 	if (err)
4323 		goto done;
4324 
4325 	err = got_ref_write(rebased_branch, repo);
4326 	if (err)
4327 		goto done;
4328 
4329 	err = got_worktree_set_head_ref(worktree, rebased_branch);
4330 	if (err)
4331 		goto done;
4332 
4333 	err = delete_rebase_refs(worktree, repo);
4334 done:
4335 	if (fileindex)
4336 		got_fileindex_free(fileindex);
4337 	free(new_head_commit_id);
4338 	unlockerr = lock_worktree(worktree, LOCK_SH);
4339 	if (unlockerr && err == NULL)
4340 		err = unlockerr;
4341 	return err;
4342 }
4343 
4344 struct collect_revertible_paths_arg {
4345 	struct got_pathlist_head *revertible_paths;
4346 	struct got_worktree *worktree;
4347 };
4348 
4349 static const struct got_error *
4350 collect_revertible_paths(void *arg, unsigned char status,
4351     unsigned char staged_status, const char *relpath,
4352     struct got_object_id *blob_id, struct got_object_id *commit_id)
4353 {
4354 	struct collect_revertible_paths_arg *a = arg;
4355 	const struct got_error *err = NULL;
4356 	struct got_pathlist_entry *new = NULL;
4357 	char *path = NULL;
4358 
4359 	if (status != GOT_STATUS_ADD &&
4360 	    status != GOT_STATUS_DELETE &&
4361 	    status != GOT_STATUS_MODIFY &&
4362 	    status != GOT_STATUS_CONFLICT &&
4363 	    status != GOT_STATUS_MISSING)
4364 		return NULL;
4365 
4366 	if (asprintf(&path, "%s/%s", a->worktree->root_path, relpath) == -1)
4367 		return got_error_from_errno("asprintf");
4368 
4369 	err = got_pathlist_insert(&new, a->revertible_paths, path, NULL);
4370 	if (err || new == NULL)
4371 		free(path);
4372 	return err;
4373 }
4374 
4375 const struct got_error *
4376 got_worktree_rebase_abort(struct got_worktree *worktree,
4377     struct got_fileindex *fileindex, struct got_repository *repo,
4378     struct got_reference *new_base_branch,
4379      got_worktree_checkout_cb progress_cb, void *progress_arg)
4380 {
4381 	const struct got_error *err, *unlockerr, *sync_err;
4382 	struct got_reference *resolved = NULL;
4383 	struct got_object_id *commit_id = NULL;
4384 	char *fileindex_path = NULL;
4385 	struct got_pathlist_head revertible_paths;
4386 	struct got_pathlist_entry *pe;
4387 	struct collect_revertible_paths_arg crp_arg;
4388 	struct got_object_id *tree_id = NULL;
4389 
4390 	TAILQ_INIT(&revertible_paths);
4391 
4392 	err = lock_worktree(worktree, LOCK_EX);
4393 	if (err)
4394 		return err;
4395 
4396 	err = got_ref_open(&resolved, repo,
4397 	    got_ref_get_symref_target(new_base_branch), 0);
4398 	if (err)
4399 		goto done;
4400 
4401 	err = got_worktree_set_head_ref(worktree, resolved);
4402 	if (err)
4403 		goto done;
4404 
4405 	/*
4406 	 * XXX commits to the base branch could have happened while
4407 	 * we were busy rebasing; should we store the original commit ID
4408 	 * when rebase begins and read it back here?
4409 	 */
4410 	err = got_ref_resolve(&commit_id, repo, resolved);
4411 	if (err)
4412 		goto done;
4413 
4414 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
4415 	if (err)
4416 		goto done;
4417 
4418 	err = got_object_id_by_path(&tree_id, repo,
4419 	    worktree->base_commit_id, worktree->path_prefix);
4420 	if (err)
4421 		goto done;
4422 
4423 	err = delete_rebase_refs(worktree, repo);
4424 	if (err)
4425 		goto done;
4426 
4427 	err = get_fileindex_path(&fileindex_path, worktree);
4428 	if (err)
4429 		goto done;
4430 
4431 	crp_arg.revertible_paths = &revertible_paths;
4432 	crp_arg.worktree = worktree;
4433 	err = worktree_status(worktree, "", fileindex, repo,
4434 	    collect_revertible_paths, &crp_arg, NULL, NULL);
4435 	if (err)
4436 		goto done;
4437 
4438 	TAILQ_FOREACH(pe, &revertible_paths, entry) {
4439 		err = revert_file(worktree, fileindex, pe->path,
4440 		    progress_cb, progress_arg, repo);
4441 		if (err)
4442 			goto sync;
4443 	}
4444 
4445 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
4446 	    repo, progress_cb, progress_arg, NULL, NULL);
4447 sync:
4448 	sync_err = sync_fileindex(fileindex, fileindex_path);
4449 	if (sync_err && err == NULL)
4450 		err = sync_err;
4451 done:
4452 	got_ref_close(resolved);
4453 	free(tree_id);
4454 	free(commit_id);
4455 	if (fileindex)
4456 		got_fileindex_free(fileindex);
4457 	free(fileindex_path);
4458 	TAILQ_FOREACH(pe, &revertible_paths, entry)
4459 		free((char *)pe->path);
4460 	got_pathlist_free(&revertible_paths);
4461 
4462 	unlockerr = lock_worktree(worktree, LOCK_SH);
4463 	if (unlockerr && err == NULL)
4464 		err = unlockerr;
4465 	return err;
4466 }
4467 
4468 const struct got_error *
4469 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
4470     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
4471     struct got_fileindex **fileindex, struct got_worktree *worktree,
4472     struct got_repository *repo)
4473 {
4474 	const struct got_error *err = NULL;
4475 	char *tmp_branch_name = NULL;
4476 	char *branch_ref_name = NULL;
4477 	char *base_commit_ref_name = NULL;
4478 	char *fileindex_path = NULL;
4479 	struct check_rebase_ok_arg ok_arg;
4480 	struct got_reference *wt_branch = NULL;
4481 	struct got_reference *base_commit_ref = NULL;
4482 
4483 	*tmp_branch = NULL;
4484 	*branch_ref = NULL;
4485 	*base_commit_id = NULL;
4486 	*fileindex = NULL;
4487 
4488 	err = lock_worktree(worktree, LOCK_EX);
4489 	if (err)
4490 		return err;
4491 
4492 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4493 	if (err)
4494 		goto done;
4495 
4496 	ok_arg.worktree = worktree;
4497 	ok_arg.repo = repo;
4498 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
4499 	    &ok_arg);
4500 	if (err)
4501 		goto done;
4502 
4503 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4504 	if (err)
4505 		goto done;
4506 
4507 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4508 	if (err)
4509 		goto done;
4510 
4511 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4512 	    worktree);
4513 	if (err)
4514 		goto done;
4515 
4516 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
4517 	    0);
4518 	if (err)
4519 		goto done;
4520 
4521 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
4522 	if (err)
4523 		goto done;
4524 
4525 	err = got_ref_write(*branch_ref, repo);
4526 	if (err)
4527 		goto done;
4528 
4529 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
4530 	    worktree->base_commit_id);
4531 	if (err)
4532 		goto done;
4533 	err = got_ref_write(base_commit_ref, repo);
4534 	if (err)
4535 		goto done;
4536 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
4537 	if (*base_commit_id == NULL) {
4538 		err = got_error_from_errno("got_object_id_dup");
4539 		goto done;
4540 	}
4541 
4542 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
4543 	    worktree->base_commit_id);
4544 	if (err)
4545 		goto done;
4546 	err = got_ref_write(*tmp_branch, repo);
4547 	if (err)
4548 		goto done;
4549 
4550 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
4551 	if (err)
4552 		goto done;
4553 done:
4554 	free(fileindex_path);
4555 	free(tmp_branch_name);
4556 	free(branch_ref_name);
4557 	free(base_commit_ref_name);
4558 	if (wt_branch)
4559 		got_ref_close(wt_branch);
4560 	if (err) {
4561 		if (*branch_ref) {
4562 			got_ref_close(*branch_ref);
4563 			*branch_ref = NULL;
4564 		}
4565 		if (*tmp_branch) {
4566 			got_ref_close(*tmp_branch);
4567 			*tmp_branch = NULL;
4568 		}
4569 		free(*base_commit_id);
4570 		if (*fileindex) {
4571 			got_fileindex_free(*fileindex);
4572 			*fileindex = NULL;
4573 		}
4574 		lock_worktree(worktree, LOCK_SH);
4575 	}
4576 	return err;
4577 }
4578 
4579 const struct got_error *
4580 got_worktree_histedit_postpone(struct got_worktree *worktree,
4581     struct got_fileindex *fileindex)
4582 {
4583 	if (fileindex)
4584 		got_fileindex_free(fileindex);
4585 	return lock_worktree(worktree, LOCK_SH);
4586 }
4587 
4588 const struct got_error *
4589 got_worktree_histedit_in_progress(int *in_progress,
4590     struct got_worktree *worktree)
4591 {
4592 	const struct got_error *err;
4593 	char *tmp_branch_name = NULL;
4594 
4595 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4596 	if (err)
4597 		return err;
4598 
4599 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
4600 	free(tmp_branch_name);
4601 	return NULL;
4602 }
4603 
4604 const struct got_error *
4605 got_worktree_histedit_continue(struct got_object_id **commit_id,
4606     struct got_reference **tmp_branch, struct got_reference **branch_ref,
4607     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
4608     struct got_worktree *worktree, struct got_repository *repo)
4609 {
4610 	const struct got_error *err;
4611 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
4612 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
4613 	struct got_reference *commit_ref = NULL;
4614 	struct got_reference *base_commit_ref = NULL;
4615 	char *fileindex_path = NULL;
4616 
4617 	*commit_id = NULL;
4618 	*tmp_branch = NULL;
4619 	*base_commit_id = NULL;
4620 	*fileindex = NULL;
4621 
4622 	err = lock_worktree(worktree, LOCK_EX);
4623 	if (err)
4624 		return err;
4625 
4626 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4627 	if (err)
4628 		goto done;
4629 
4630 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4631 	if (err)
4632 		return err;
4633 
4634 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4635 	if (err)
4636 		goto done;
4637 
4638 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4639 	if (err)
4640 		goto done;
4641 
4642 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4643 	    worktree);
4644 	if (err)
4645 		goto done;
4646 
4647 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
4648 	if (err)
4649 		goto done;
4650 
4651 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4652 	if (err)
4653 		goto done;
4654 	err = got_ref_resolve(commit_id, repo, commit_ref);
4655 	if (err)
4656 		goto done;
4657 
4658 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
4659 	if (err)
4660 		goto done;
4661 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
4662 	if (err)
4663 		goto done;
4664 
4665 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
4666 	if (err)
4667 		goto done;
4668 done:
4669 	free(commit_ref_name);
4670 	free(branch_ref_name);
4671 	free(fileindex_path);
4672 	if (commit_ref)
4673 		got_ref_close(commit_ref);
4674 	if (base_commit_ref)
4675 		got_ref_close(base_commit_ref);
4676 	if (err) {
4677 		free(*commit_id);
4678 		*commit_id = NULL;
4679 		free(*base_commit_id);
4680 		*base_commit_id = NULL;
4681 		if (*tmp_branch) {
4682 			got_ref_close(*tmp_branch);
4683 			*tmp_branch = NULL;
4684 		}
4685 		if (*fileindex) {
4686 			got_fileindex_free(*fileindex);
4687 			*fileindex = NULL;
4688 		}
4689 		lock_worktree(worktree, LOCK_EX);
4690 	}
4691 	return err;
4692 }
4693 
4694 static const struct got_error *
4695 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
4696 {
4697 	const struct got_error *err;
4698 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
4699 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
4700 
4701 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4702 	if (err)
4703 		goto done;
4704 	err = delete_ref(tmp_branch_name, repo);
4705 	if (err)
4706 		goto done;
4707 
4708 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4709 	    worktree);
4710 	if (err)
4711 		goto done;
4712 	err = delete_ref(base_commit_ref_name, repo);
4713 	if (err)
4714 		goto done;
4715 
4716 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4717 	if (err)
4718 		goto done;
4719 	err = delete_ref(branch_ref_name, repo);
4720 	if (err)
4721 		goto done;
4722 
4723 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4724 	if (err)
4725 		goto done;
4726 	err = delete_ref(commit_ref_name, repo);
4727 	if (err)
4728 		goto done;
4729 done:
4730 	free(tmp_branch_name);
4731 	free(base_commit_ref_name);
4732 	free(branch_ref_name);
4733 	free(commit_ref_name);
4734 	return err;
4735 }
4736 
4737 const struct got_error *
4738 got_worktree_histedit_abort(struct got_worktree *worktree,
4739     struct got_fileindex *fileindex, struct got_repository *repo,
4740     struct got_reference *branch, struct got_object_id *base_commit_id,
4741     got_worktree_checkout_cb progress_cb, void *progress_arg)
4742 {
4743 	const struct got_error *err, *unlockerr, *sync_err;
4744 	struct got_reference *resolved = NULL;
4745 	char *fileindex_path = NULL;
4746 	struct got_pathlist_head revertible_paths;
4747 	struct got_pathlist_entry *pe;
4748 	struct collect_revertible_paths_arg crp_arg;
4749 	struct got_object_id *tree_id = NULL;
4750 
4751 	TAILQ_INIT(&revertible_paths);
4752 
4753 	err = lock_worktree(worktree, LOCK_EX);
4754 	if (err)
4755 		return err;
4756 
4757 	err = got_ref_open(&resolved, repo,
4758 	    got_ref_get_symref_target(branch), 0);
4759 	if (err)
4760 		goto done;
4761 
4762 	err = got_worktree_set_head_ref(worktree, resolved);
4763 	if (err)
4764 		goto done;
4765 
4766 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
4767 	if (err)
4768 		goto done;
4769 
4770 	err = got_object_id_by_path(&tree_id, repo, base_commit_id,
4771 	    worktree->path_prefix);
4772 	if (err)
4773 		goto done;
4774 
4775 	err = delete_histedit_refs(worktree, repo);
4776 	if (err)
4777 		goto done;
4778 
4779 	err = get_fileindex_path(&fileindex_path, worktree);
4780 	if (err)
4781 		goto done;
4782 
4783 	crp_arg.revertible_paths = &revertible_paths;
4784 	crp_arg.worktree = worktree;
4785 	err = worktree_status(worktree, "", fileindex, repo,
4786 	    collect_revertible_paths, &crp_arg, NULL, NULL);
4787 	if (err)
4788 		goto done;
4789 
4790 	TAILQ_FOREACH(pe, &revertible_paths, entry) {
4791 		err = revert_file(worktree, fileindex, pe->path,
4792 		    progress_cb, progress_arg, repo);
4793 		if (err)
4794 			goto sync;
4795 	}
4796 
4797 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
4798 	    repo, progress_cb, progress_arg, NULL, NULL);
4799 sync:
4800 	sync_err = sync_fileindex(fileindex, fileindex_path);
4801 	if (sync_err && err == NULL)
4802 		err = sync_err;
4803 done:
4804 	got_ref_close(resolved);
4805 	free(tree_id);
4806 	free(fileindex_path);
4807 	TAILQ_FOREACH(pe, &revertible_paths, entry)
4808 		free((char *)pe->path);
4809 	got_pathlist_free(&revertible_paths);
4810 
4811 	unlockerr = lock_worktree(worktree, LOCK_SH);
4812 	if (unlockerr && err == NULL)
4813 		err = unlockerr;
4814 	return err;
4815 }
4816 
4817 const struct got_error *
4818 got_worktree_histedit_complete(struct got_worktree *worktree,
4819     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4820     struct got_reference *edited_branch, struct got_repository *repo)
4821 {
4822 	const struct got_error *err, *unlockerr;
4823 	struct got_object_id *new_head_commit_id = NULL;
4824 	struct got_reference *resolved = NULL;
4825 
4826 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
4827 	if (err)
4828 		return err;
4829 
4830 	err = got_ref_open(&resolved, repo,
4831 	    got_ref_get_symref_target(edited_branch), 0);
4832 	if (err)
4833 		goto done;
4834 
4835 	err = got_ref_change_ref(resolved, new_head_commit_id);
4836 	if (err)
4837 		goto done;
4838 
4839 	err = got_ref_write(resolved, repo);
4840 	if (err)
4841 		goto done;
4842 
4843 	err = got_worktree_set_head_ref(worktree, resolved);
4844 	if (err)
4845 		goto done;
4846 
4847 	err = delete_histedit_refs(worktree, repo);
4848 done:
4849 	if (fileindex)
4850 		got_fileindex_free(fileindex);
4851 	free(new_head_commit_id);
4852 	unlockerr = lock_worktree(worktree, LOCK_SH);
4853 	if (unlockerr && err == NULL)
4854 		err = unlockerr;
4855 	return err;
4856 }
4857 
4858 const struct got_error *
4859 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
4860     struct got_object_id *commit_id, struct got_repository *repo)
4861 {
4862 	const struct got_error *err;
4863 	char *commit_ref_name;
4864 
4865 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4866 	if (err)
4867 		return err;
4868 
4869 	err = store_commit_id(commit_ref_name, commit_id, repo);
4870 	if (err)
4871 		goto done;
4872 
4873 	err = delete_ref(commit_ref_name, repo);
4874 done:
4875 	free(commit_ref_name);
4876 	return err;
4877 }
4878 
4879 static const struct got_error *
4880 stage_path(const char *relpath, const char *ondisk_path,
4881     const char *path_content, struct got_worktree *worktree,
4882     struct got_fileindex *fileindex, struct got_repository *repo,
4883     got_worktree_status_cb status_cb, void *status_arg)
4884 {
4885 	const struct got_error *err = NULL;
4886 	struct got_fileindex_entry *ie;
4887 	unsigned char status;
4888 	struct stat sb;
4889 	struct got_object_id *blob_id = NULL;
4890 	uint32_t stage;
4891 
4892 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
4893 	if (ie == NULL) {
4894 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4895 		goto done;
4896 	}
4897 
4898 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
4899 	if (err)
4900 		goto done;
4901 
4902 	switch (status) {
4903 	case GOT_STATUS_ADD:
4904 	case GOT_STATUS_MODIFY:
4905 		err = got_object_blob_create(&blob_id,
4906 		    path_content ? path_content : ondisk_path, repo);
4907 		if (err)
4908 			goto done;
4909 		memcpy(ie->staged_blob_sha1, blob_id->sha1,
4910 		    SHA1_DIGEST_LENGTH);
4911 		if (status == GOT_STATUS_ADD)
4912 			stage = GOT_FILEIDX_STAGE_ADD;
4913 		else
4914 			stage = GOT_FILEIDX_STAGE_MODIFY;
4915 		break;
4916 	case GOT_STATUS_DELETE:
4917 		stage = GOT_FILEIDX_STAGE_DELETE;
4918 		break;
4919 	default:
4920 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4921 		goto done;
4922 	}
4923 
4924 	got_fileindex_entry_stage_set(ie, stage);
4925 	err = (*status_cb)(status_arg, GOT_STATUS_NO_CHANGE,
4926 	    get_staged_status(ie), relpath, blob_id, NULL);
4927 done:
4928 	free(blob_id);
4929 	return err;
4930 }
4931 
4932 const struct got_error *
4933 got_worktree_stage(struct got_worktree *worktree,
4934     struct got_pathlist_head *paths,
4935     got_worktree_status_cb status_cb, void *status_arg,
4936     struct got_repository *repo)
4937 {
4938 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4939 	struct got_pathlist_entry *pe;
4940 	struct got_fileindex *fileindex = NULL;
4941 	char *fileindex_path = NULL;
4942 
4943 	err = lock_worktree(worktree, LOCK_EX);
4944 	if (err)
4945 		return err;
4946 
4947 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4948 	if (err)
4949 		goto done;
4950 
4951 	TAILQ_FOREACH(pe, paths, entry) {
4952 		char *relpath;
4953 		err = got_path_skip_common_ancestor(&relpath,
4954 		    got_worktree_get_root_path(worktree), pe->path);
4955 		if (err)
4956 			break;
4957 		err = stage_path(relpath, pe->path,
4958 		    (const char *)pe->data, worktree, fileindex, repo,
4959 		    status_cb, status_arg);
4960 		free(relpath);
4961 		if (err)
4962 			break;
4963 	}
4964 
4965 	sync_err = sync_fileindex(fileindex, fileindex_path);
4966 	if (sync_err && err == NULL)
4967 		err = sync_err;
4968 done:
4969 	free(fileindex_path);
4970 	if (fileindex)
4971 		got_fileindex_free(fileindex);
4972 	unlockerr = lock_worktree(worktree, LOCK_SH);
4973 	if (unlockerr && err == NULL)
4974 		err = unlockerr;
4975 	return err;
4976 }