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 unsigned char
1038 get_staged_status(struct got_fileindex_entry *ie)
1039 {
1040 	switch (got_fileindex_entry_stage_get(ie)) {
1041 	case GOT_FILEIDX_STAGE_ADD:
1042 		return GOT_STATUS_ADD;
1043 	case GOT_FILEIDX_STAGE_DELETE:
1044 		return GOT_STATUS_DELETE;
1045 	case GOT_FILEIDX_STAGE_MODIFY:
1046 		return GOT_STATUS_MODIFY;
1047 	default:
1048 		return GOT_STATUS_NO_CHANGE;
1049 	}
1050 }
1051 
1052 static const struct got_error *
1053 get_file_status(unsigned char *status, struct stat *sb,
1054     struct got_fileindex_entry *ie, const char *abspath,
1055     struct got_repository *repo)
1056 {
1057 	const struct got_error *err = NULL;
1058 	struct got_object_id id;
1059 	size_t hdrlen;
1060 	FILE *f = NULL;
1061 	uint8_t fbuf[8192];
1062 	struct got_blob_object *blob = NULL;
1063 	size_t flen, blen;
1064 	unsigned char staged_status = get_staged_status(ie);
1065 
1066 	*status = GOT_STATUS_NO_CHANGE;
1067 
1068 	if (lstat(abspath, sb) == -1) {
1069 		if (errno == ENOENT) {
1070 			if (got_fileindex_entry_has_file_on_disk(ie))
1071 				*status = GOT_STATUS_MISSING;
1072 			else
1073 				*status = GOT_STATUS_DELETE;
1074 			return NULL;
1075 		}
1076 		return got_error_from_errno2("lstat", abspath);
1077 	}
1078 
1079 	if (!S_ISREG(sb->st_mode)) {
1080 		*status = GOT_STATUS_OBSTRUCTED;
1081 		return NULL;
1082 	}
1083 
1084 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1085 		*status = GOT_STATUS_DELETE;
1086 		return NULL;
1087 	} else if (!got_fileindex_entry_has_blob(ie)) {
1088 		*status = GOT_STATUS_ADD;
1089 		return NULL;
1090 	}
1091 
1092 	if (!stat_info_differs(ie, sb))
1093 		return NULL;
1094 
1095 	if (staged_status == GOT_STATUS_MODIFY ||
1096 	    staged_status == GOT_STATUS_ADD)
1097 		memcpy(id.sha1, ie->staged_blob_sha1, sizeof(id.sha1));
1098 	else
1099 		memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1100 
1101 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1102 	if (err)
1103 		return err;
1104 
1105 	f = fopen(abspath, "r");
1106 	if (f == NULL) {
1107 		err = got_error_from_errno2("fopen", abspath);
1108 		goto done;
1109 	}
1110 	hdrlen = got_object_blob_get_hdrlen(blob);
1111 	for (;;) {
1112 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1113 		err = got_object_blob_read_block(&blen, blob);
1114 		if (err)
1115 			goto done;
1116 		/* Skip length of blob object header first time around. */
1117 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1118 		if (flen == 0 && ferror(f)) {
1119 			err = got_error_from_errno("fread");
1120 			goto done;
1121 		}
1122 		if (blen == 0) {
1123 			if (flen != 0)
1124 				*status = GOT_STATUS_MODIFY;
1125 			break;
1126 		} else if (flen == 0) {
1127 			if (blen != 0)
1128 				*status = GOT_STATUS_MODIFY;
1129 			break;
1130 		} else if (blen - hdrlen == flen) {
1131 			/* Skip blob object header first time around. */
1132 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1133 				*status = GOT_STATUS_MODIFY;
1134 				break;
1135 			}
1136 		} else {
1137 			*status = GOT_STATUS_MODIFY;
1138 			break;
1139 		}
1140 		hdrlen = 0;
1141 	}
1142 
1143 	if (*status == GOT_STATUS_MODIFY) {
1144 		rewind(f);
1145 		err = get_modified_file_content_status(status, f);
1146 	}
1147 done:
1148 	if (blob)
1149 		got_object_blob_close(blob);
1150 	if (f)
1151 		fclose(f);
1152 	return err;
1153 }
1154 
1155 /*
1156  * Update timestamps in the file index if a file is unmodified and
1157  * we had to run a full content comparison to find out.
1158  */
1159 static const struct got_error *
1160 sync_timestamps(char *ondisk_path, unsigned char status,
1161     struct got_fileindex_entry *ie, struct stat *sb)
1162 {
1163 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1164 		return got_fileindex_entry_update(ie, ondisk_path,
1165 		    ie->blob_sha1, ie->commit_sha1, 1);
1166 
1167 	return NULL;
1168 }
1169 
1170 static const struct got_error *
1171 update_blob(struct got_worktree *worktree,
1172     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1173     struct got_tree_entry *te, const char *path,
1174     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1175     void *progress_arg)
1176 {
1177 	const struct got_error *err = NULL;
1178 	struct got_blob_object *blob = NULL;
1179 	char *ondisk_path;
1180 	unsigned char status = GOT_STATUS_NO_CHANGE;
1181 	struct stat sb;
1182 
1183 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1184 		return got_error_from_errno("asprintf");
1185 
1186 	if (ie) {
1187 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1188 		if (err)
1189 			goto done;
1190 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1191 			sb.st_mode = got_fileindex_perms_to_st(ie);
1192 	} else
1193 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
1194 
1195 	if (status == GOT_STATUS_OBSTRUCTED) {
1196 		err = (*progress_cb)(progress_arg, status, path);
1197 		goto done;
1198 	}
1199 
1200 	if (ie && status != GOT_STATUS_MISSING) {
1201 		if (got_fileindex_entry_has_commit(ie) &&
1202 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1203 		    SHA1_DIGEST_LENGTH) == 0) {
1204 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1205 			if (err)
1206 				goto done;
1207 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1208 			    path);
1209 			goto done;
1210 		}
1211 		if (got_fileindex_entry_has_blob(ie) &&
1212 		    memcmp(ie->blob_sha1, te->id->sha1,
1213 		    SHA1_DIGEST_LENGTH) == 0) {
1214 			err = sync_timestamps(ondisk_path, status, ie, &sb);
1215 			goto done;
1216 		}
1217 	}
1218 
1219 	err = got_object_open_as_blob(&blob, repo, te->id, 8192);
1220 	if (err)
1221 		goto done;
1222 
1223 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1224 		int update_timestamps;
1225 		struct got_blob_object *blob2 = NULL;
1226 		if (got_fileindex_entry_has_blob(ie)) {
1227 			struct got_object_id id2;
1228 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
1229 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
1230 			if (err)
1231 				goto done;
1232 		}
1233 		err = merge_blob(&update_timestamps, worktree, blob2,
1234 		    ondisk_path, path, sb.st_mode, blob,
1235 		    worktree->base_commit_id, repo,
1236 		    progress_cb, progress_arg);
1237 		if (blob2)
1238 			got_object_blob_close(blob2);
1239 		/*
1240 		 * Do not update timestamps of files with local changes.
1241 		 * Otherwise, a future status walk would treat them as
1242 		 * unmodified files again.
1243 		 */
1244 		err = got_fileindex_entry_update(ie, ondisk_path,
1245 		    blob->id.sha1, worktree->base_commit_id->sha1,
1246 		    update_timestamps);
1247 	} else if (status == GOT_STATUS_DELETE) {
1248 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1249 		if (err)
1250 			goto done;
1251 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1252 		    ondisk_path, path, blob, 0);
1253 		if (err)
1254 			goto done;
1255 	} else {
1256 		err = install_blob(worktree, ondisk_path, path, te->mode,
1257 		    sb.st_mode, blob, status == GOT_STATUS_MISSING, 0,
1258 		    repo, progress_cb, progress_arg);
1259 		if (err)
1260 			goto done;
1261 		err = update_blob_fileindex_entry(worktree, fileindex, ie,
1262 		    ondisk_path, path, blob, 1);
1263 		if (err)
1264 			goto done;
1265 	}
1266 	got_object_blob_close(blob);
1267 done:
1268 	free(ondisk_path);
1269 	return err;
1270 }
1271 
1272 static const struct got_error *
1273 remove_ondisk_file(const char *root_path, const char *path)
1274 {
1275 	const struct got_error *err = NULL;
1276 	char *ondisk_path = NULL;
1277 
1278 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
1279 		return got_error_from_errno("asprintf");
1280 
1281 	if (unlink(ondisk_path) == -1) {
1282 		if (errno != ENOENT)
1283 			err = got_error_from_errno2("unlink", ondisk_path);
1284 	} else {
1285 		char *parent = dirname(ondisk_path);
1286 		while (parent && strcmp(parent, root_path) != 0) {
1287 			if (rmdir(parent) == -1) {
1288 				if (errno != ENOTEMPTY)
1289 					err = got_error_from_errno2("rmdir",
1290 					    parent);
1291 				break;
1292 			}
1293 			parent = dirname(parent);
1294 		}
1295 	}
1296 	free(ondisk_path);
1297 	return err;
1298 }
1299 
1300 static const struct got_error *
1301 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
1302     struct got_fileindex_entry *ie, struct got_repository *repo,
1303     got_worktree_checkout_cb progress_cb, void *progress_arg)
1304 {
1305 	const struct got_error *err = NULL;
1306 	unsigned char status;
1307 	struct stat sb;
1308 	char *ondisk_path;
1309 
1310 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
1311 	    == -1)
1312 		return got_error_from_errno("asprintf");
1313 
1314 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1315 	if (err)
1316 		return err;
1317 
1318 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
1319 	    status == GOT_STATUS_ADD) {
1320 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
1321 		if (err)
1322 			return err;
1323 		/*
1324 		 * Preserve the working file and change the deleted blob's
1325 		 * entry into a schedule-add entry.
1326 		 */
1327 		err = got_fileindex_entry_update(ie, ondisk_path, NULL, NULL,
1328 		    0);
1329 		if (err)
1330 			return err;
1331 	} else {
1332 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
1333 		if (err)
1334 			return err;
1335 		if (status == GOT_STATUS_NO_CHANGE) {
1336 			err = remove_ondisk_file(worktree->root_path, ie->path);
1337 			if (err)
1338 				return err;
1339 		}
1340 		got_fileindex_entry_remove(fileindex, ie);
1341 	}
1342 
1343 	return err;
1344 }
1345 
1346 struct diff_cb_arg {
1347     struct got_fileindex *fileindex;
1348     struct got_worktree *worktree;
1349     struct got_repository *repo;
1350     got_worktree_checkout_cb progress_cb;
1351     void *progress_arg;
1352     got_worktree_cancel_cb cancel_cb;
1353     void *cancel_arg;
1354 };
1355 
1356 static const struct got_error *
1357 diff_old_new(void *arg, struct got_fileindex_entry *ie,
1358     struct got_tree_entry *te, const char *parent_path)
1359 {
1360 	struct diff_cb_arg *a = arg;
1361 
1362 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1363 		return got_error(GOT_ERR_CANCELLED);
1364 
1365 	return update_blob(a->worktree, a->fileindex, ie, te,
1366 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
1367 }
1368 
1369 static const struct got_error *
1370 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
1371 {
1372 	struct diff_cb_arg *a = arg;
1373 
1374 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1375 		return got_error(GOT_ERR_CANCELLED);
1376 
1377 	return delete_blob(a->worktree, a->fileindex, ie,
1378 	    a->repo, a->progress_cb, a->progress_arg);
1379 }
1380 
1381 static const struct got_error *
1382 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
1383 {
1384 	struct diff_cb_arg *a = arg;
1385 	const struct got_error *err;
1386 	char *path;
1387 
1388 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
1389 		return got_error(GOT_ERR_CANCELLED);
1390 
1391 	if (asprintf(&path, "%s%s%s", parent_path,
1392 	    parent_path[0] ? "/" : "", te->name)
1393 	    == -1)
1394 		return got_error_from_errno("asprintf");
1395 
1396 	if (S_ISDIR(te->mode))
1397 		err = add_dir_on_disk(a->worktree, path);
1398 	else
1399 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
1400 		    a->repo, a->progress_cb, a->progress_arg);
1401 
1402 	free(path);
1403 	return err;
1404 }
1405 
1406 static const struct got_error *
1407 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
1408 {
1409 	const struct got_error *err = NULL;
1410 	char *uuidstr = NULL;
1411 	uint32_t uuid_status;
1412 
1413 	*refname = NULL;
1414 
1415 	uuid_to_string(&worktree->uuid, &uuidstr, &uuid_status);
1416 	if (uuid_status != uuid_s_ok)
1417 		return got_error_uuid(uuid_status);
1418 
1419 	if (asprintf(refname, "%s-%s", prefix, uuidstr)
1420 	    == -1) {
1421 		err = got_error_from_errno("asprintf");
1422 		*refname = NULL;
1423 	}
1424 	free(uuidstr);
1425 	return err;
1426 }
1427 
1428 const struct got_error *
1429 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
1430 {
1431 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
1432 }
1433 
1434 static const struct got_error *
1435 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
1436 {
1437 	return get_ref_name(refname, worktree,
1438 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
1439 }
1440 
1441 static const struct got_error *
1442 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
1443 {
1444 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
1445 }
1446 
1447 static const struct got_error *
1448 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
1449 {
1450 	return get_ref_name(refname, worktree,
1451 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
1452 }
1453 
1454 static const struct got_error *
1455 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
1456 {
1457 	return get_ref_name(refname, worktree,
1458 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
1459 }
1460 
1461 static const struct got_error *
1462 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
1463 {
1464 	return get_ref_name(refname, worktree,
1465 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
1466 }
1467 
1468 static const struct got_error *
1469 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
1470 {
1471 	return get_ref_name(refname, worktree,
1472 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
1473 }
1474 
1475 static const struct got_error *
1476 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
1477 {
1478 	return get_ref_name(refname, worktree,
1479 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
1480 }
1481 
1482 static const struct got_error *
1483 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
1484 {
1485 	return get_ref_name(refname, worktree,
1486 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
1487 }
1488 
1489 const struct got_error *
1490 got_worktree_get_histedit_script_path(char **path,
1491     struct got_worktree *worktree)
1492 {
1493 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
1494 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
1495 		*path = NULL;
1496 		return got_error_from_errno("asprintf");
1497 	}
1498 	return NULL;
1499 }
1500 
1501 /*
1502  * Prevent Git's garbage collector from deleting our base commit by
1503  * setting a reference to our base commit's ID.
1504  */
1505 static const struct got_error *
1506 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
1507 {
1508 	const struct got_error *err = NULL;
1509 	struct got_reference *ref = NULL;
1510 	char *refname;
1511 
1512 	err = got_worktree_get_base_ref_name(&refname, worktree);
1513 	if (err)
1514 		return err;
1515 
1516 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
1517 	if (err)
1518 		goto done;
1519 
1520 	err = got_ref_write(ref, repo);
1521 done:
1522 	free(refname);
1523 	if (ref)
1524 		got_ref_close(ref);
1525 	return err;
1526 }
1527 
1528 static const struct got_error *
1529 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
1530 {
1531 	const struct got_error *err = NULL;
1532 
1533 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
1534 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
1535 		err = got_error_from_errno("asprintf");
1536 		*fileindex_path = NULL;
1537 	}
1538 	return err;
1539 }
1540 
1541 
1542 static const struct got_error *
1543 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
1544    struct got_worktree *worktree)
1545 {
1546 	const struct got_error *err = NULL;
1547 	FILE *index = NULL;
1548 
1549 	*fileindex_path = NULL;
1550 	*fileindex = got_fileindex_alloc();
1551 	if (*fileindex == NULL)
1552 		return got_error_from_errno("got_fileindex_alloc");
1553 
1554 	err = get_fileindex_path(fileindex_path, worktree);
1555 	if (err)
1556 		goto done;
1557 
1558 	index = fopen(*fileindex_path, "rb");
1559 	if (index == NULL) {
1560 		if (errno != ENOENT)
1561 			err = got_error_from_errno2("fopen", *fileindex_path);
1562 	} else {
1563 		err = got_fileindex_read(*fileindex, index);
1564 		if (fclose(index) != 0 && err == NULL)
1565 			err = got_error_from_errno("fclose");
1566 	}
1567 done:
1568 	if (err) {
1569 		free(*fileindex_path);
1570 		*fileindex_path = NULL;
1571 		got_fileindex_free(*fileindex);
1572 		*fileindex = NULL;
1573 	}
1574 	return err;
1575 }
1576 
1577 struct bump_base_commit_id_arg {
1578 	struct got_object_id *base_commit_id;
1579 	const char *path;
1580 	size_t path_len;
1581 	const char *entry_name;
1582 	got_worktree_checkout_cb progress_cb;
1583 	void *progress_arg;
1584 };
1585 
1586 /* Bump base commit ID of all files within an updated part of the work tree. */
1587 static const struct got_error *
1588 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
1589 {
1590 	const struct got_error *err;
1591 	struct bump_base_commit_id_arg *a = arg;
1592 
1593 	if (a->entry_name) {
1594 		if (strcmp(ie->path, a->path) != 0)
1595 			return NULL;
1596 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
1597 		return NULL;
1598 
1599 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
1600 	    SHA1_DIGEST_LENGTH) == 0)
1601 		return NULL;
1602 
1603 	if (a->progress_cb) {
1604 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
1605 		    ie->path);
1606 		if (err)
1607 			return err;
1608 	}
1609 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
1610 	return NULL;
1611 }
1612 
1613 static const struct got_error *
1614 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
1615 {
1616 	const struct got_error *err = NULL;
1617 	char *new_fileindex_path = NULL;
1618 	FILE *new_index = NULL;
1619 
1620 	err = got_opentemp_named(&new_fileindex_path, &new_index,
1621 	    fileindex_path);
1622 	if (err)
1623 		goto done;
1624 
1625 	err = got_fileindex_write(fileindex, new_index);
1626 	if (err)
1627 		goto done;
1628 
1629 	if (rename(new_fileindex_path, fileindex_path) != 0) {
1630 		err = got_error_from_errno3("rename", new_fileindex_path,
1631 		    fileindex_path);
1632 		unlink(new_fileindex_path);
1633 	}
1634 done:
1635 	if (new_index)
1636 		fclose(new_index);
1637 	free(new_fileindex_path);
1638 	return err;
1639 }
1640 
1641 static const struct got_error *
1642 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
1643     struct got_object_id **tree_id, const char *wt_relpath,
1644     struct got_worktree *worktree, struct got_repository *repo)
1645 {
1646 	const struct got_error *err = NULL;
1647 	struct got_object_id *id = NULL;
1648 	char *in_repo_path = NULL;
1649 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
1650 
1651 	*entry_type = GOT_OBJ_TYPE_ANY;
1652 	*tree_relpath = NULL;
1653 	*tree_id = NULL;
1654 
1655 	if (wt_relpath[0] == '\0') {
1656 		/* Check out all files within the work tree. */
1657 		*entry_type = GOT_OBJ_TYPE_TREE;
1658 		*tree_relpath = strdup("");
1659 		if (*tree_relpath == NULL) {
1660 			err = got_error_from_errno("strdup");
1661 			goto done;
1662 		}
1663 		err = got_object_id_by_path(tree_id, repo,
1664 		    worktree->base_commit_id, worktree->path_prefix);
1665 		if (err)
1666 			goto done;
1667 		return NULL;
1668 	}
1669 
1670 	/* Check out a subset of files in the work tree. */
1671 
1672 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
1673 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
1674 		err = got_error_from_errno("asprintf");
1675 		goto done;
1676 	}
1677 
1678 	err = got_object_id_by_path(&id, repo, worktree->base_commit_id,
1679 	    in_repo_path);
1680 	if (err)
1681 		goto done;
1682 
1683 	free(in_repo_path);
1684 	in_repo_path = NULL;
1685 
1686 	err = got_object_get_type(entry_type, repo, id);
1687 	if (err)
1688 		goto done;
1689 
1690 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
1691 		/* Check out a single file. */
1692 		if (strchr(wt_relpath, '/')  == NULL) {
1693 			/* Check out a single file in work tree's root dir. */
1694 			in_repo_path = strdup(worktree->path_prefix);
1695 			if (in_repo_path == NULL) {
1696 				err = got_error_from_errno("strdup");
1697 				goto done;
1698 			}
1699 			*tree_relpath = strdup("");
1700 			if (*tree_relpath == NULL) {
1701 				err = got_error_from_errno("strdup");
1702 				goto done;
1703 			}
1704 		} else {
1705 			/* Check out a single file in a subdirectory. */
1706 			err = got_path_dirname(tree_relpath, wt_relpath);
1707 			if (err)
1708 				return err;
1709 			if (asprintf(&in_repo_path, "%s%s%s",
1710 			    worktree->path_prefix, is_root_wt ? "" : "/",
1711 			    *tree_relpath) == -1) {
1712 				err = got_error_from_errno("asprintf");
1713 				goto done;
1714 			}
1715 		}
1716 		err = got_object_id_by_path(tree_id, repo,
1717 		    worktree->base_commit_id, in_repo_path);
1718 	} else {
1719 		/* Check out all files within a subdirectory. */
1720 		*tree_id = got_object_id_dup(id);
1721 		if (*tree_id == NULL) {
1722 			err = got_error_from_errno("got_object_id_dup");
1723 			goto done;
1724 		}
1725 		*tree_relpath = strdup(wt_relpath);
1726 		if (*tree_relpath == NULL) {
1727 			err = got_error_from_errno("strdup");
1728 			goto done;
1729 		}
1730 	}
1731 done:
1732 	free(id);
1733 	free(in_repo_path);
1734 	if (err) {
1735 		*entry_type = GOT_OBJ_TYPE_ANY;
1736 		free(*tree_relpath);
1737 		*tree_relpath = NULL;
1738 		free(*tree_id);
1739 		*tree_id = NULL;
1740 	}
1741 	return err;
1742 }
1743 
1744 static const struct got_error *
1745 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
1746     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
1747     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1748     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1749 {
1750 	const struct got_error *err = NULL;
1751 	struct got_commit_object *commit = NULL;
1752 	struct got_tree_object *tree = NULL;
1753 	struct got_fileindex_diff_tree_cb diff_cb;
1754 	struct diff_cb_arg arg;
1755 
1756 	err = ref_base_commit(worktree, repo);
1757 	if (err)
1758 		goto done;
1759 
1760 	err = got_object_open_as_commit(&commit, repo,
1761 	   worktree->base_commit_id);
1762 	if (err)
1763 		goto done;
1764 
1765 	err = got_object_open_as_tree(&tree, repo, tree_id);
1766 	if (err)
1767 		goto done;
1768 
1769 	if (entry_name &&
1770 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
1771 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1772 		goto done;
1773 	}
1774 
1775 	diff_cb.diff_old_new = diff_old_new;
1776 	diff_cb.diff_old = diff_old;
1777 	diff_cb.diff_new = diff_new;
1778 	arg.fileindex = fileindex;
1779 	arg.worktree = worktree;
1780 	arg.repo = repo;
1781 	arg.progress_cb = progress_cb;
1782 	arg.progress_arg = progress_arg;
1783 	arg.cancel_cb = cancel_cb;
1784 	arg.cancel_arg = cancel_arg;
1785 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
1786 	    entry_name, repo, &diff_cb, &arg);
1787 done:
1788 	if (tree)
1789 		got_object_tree_close(tree);
1790 	if (commit)
1791 		got_object_commit_close(commit);
1792 	return err;
1793 }
1794 
1795 const struct got_error *
1796 got_worktree_checkout_files(struct got_worktree *worktree,
1797     struct got_pathlist_head *paths, struct got_repository *repo,
1798     got_worktree_checkout_cb progress_cb, void *progress_arg,
1799     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
1800 {
1801 	const struct got_error *err = NULL, *sync_err, *unlockerr;
1802 	struct got_commit_object *commit = NULL;
1803 	struct got_tree_object *tree = NULL;
1804 	struct got_fileindex *fileindex = NULL;
1805 	char *fileindex_path = NULL;
1806 	struct got_pathlist_entry *pe;
1807 	struct tree_path_data {
1808 		SIMPLEQ_ENTRY(tree_path_data) entry;
1809 		struct got_object_id *tree_id;
1810 		int entry_type;
1811 		char *relpath;
1812 		char *entry_name;
1813 	} *tpd = NULL;
1814 	SIMPLEQ_HEAD(tree_paths, tree_path_data) tree_paths;
1815 
1816 	SIMPLEQ_INIT(&tree_paths);
1817 
1818 	err = lock_worktree(worktree, LOCK_EX);
1819 	if (err)
1820 		return err;
1821 
1822 	/* Map all specified paths to in-repository trees. */
1823 	TAILQ_FOREACH(pe, paths, entry) {
1824 		tpd = malloc(sizeof(*tpd));
1825 		if (tpd == NULL) {
1826 			err = got_error_from_errno("malloc");
1827 			goto done;
1828 		}
1829 
1830 		err = find_tree_entry_for_checkout(&tpd->entry_type,
1831 		    &tpd->relpath, &tpd->tree_id, pe->path, worktree, repo);
1832 		if (err) {
1833 			free(tpd);
1834 			goto done;
1835 		}
1836 
1837 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
1838 			err = got_path_basename(&tpd->entry_name, pe->path);
1839 			if (err) {
1840 				free(tpd->relpath);
1841 				free(tpd->tree_id);
1842 				free(tpd);
1843 				goto done;
1844 			}
1845 		} else
1846 			tpd->entry_name = NULL;
1847 
1848 		SIMPLEQ_INSERT_TAIL(&tree_paths, tpd, entry);
1849 	}
1850 
1851 	/*
1852 	 * Read the file index.
1853 	 * Checking out files is supposed to be an idempotent operation.
1854 	 * If the on-disk file index is incomplete we will try to complete it.
1855 	 */
1856 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
1857 	if (err)
1858 		goto done;
1859 
1860 	tpd = SIMPLEQ_FIRST(&tree_paths);
1861 	TAILQ_FOREACH(pe, paths, entry) {
1862 		struct bump_base_commit_id_arg bbc_arg;
1863 
1864 		err = checkout_files(worktree, fileindex, tpd->relpath,
1865 		    tpd->tree_id, tpd->entry_name, repo,
1866 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
1867 		if (err)
1868 			break;
1869 
1870 		bbc_arg.base_commit_id = worktree->base_commit_id;
1871 		bbc_arg.entry_name = tpd->entry_name;
1872 		bbc_arg.path = pe->path;
1873 		bbc_arg.path_len = pe->path_len;
1874 		bbc_arg.progress_cb = progress_cb;
1875 		bbc_arg.progress_arg = progress_arg;
1876 		err = got_fileindex_for_each_entry_safe(fileindex,
1877 		    bump_base_commit_id, &bbc_arg);
1878 		if (err)
1879 			break;
1880 
1881 		tpd = SIMPLEQ_NEXT(tpd, entry);
1882 	}
1883 	sync_err = sync_fileindex(fileindex, fileindex_path);
1884 	if (sync_err && err == NULL)
1885 		err = sync_err;
1886 done:
1887 	free(fileindex_path);
1888 	if (tree)
1889 		got_object_tree_close(tree);
1890 	if (commit)
1891 		got_object_commit_close(commit);
1892 	if (fileindex)
1893 		got_fileindex_free(fileindex);
1894 	while (!SIMPLEQ_EMPTY(&tree_paths)) {
1895 		tpd = SIMPLEQ_FIRST(&tree_paths);
1896 		SIMPLEQ_REMOVE_HEAD(&tree_paths, entry);
1897 		free(tpd->relpath);
1898 		free(tpd->tree_id);
1899 		free(tpd);
1900 	}
1901 	unlockerr = lock_worktree(worktree, LOCK_SH);
1902 	if (unlockerr && err == NULL)
1903 		err = unlockerr;
1904 	return err;
1905 }
1906 
1907 struct merge_file_cb_arg {
1908     struct got_worktree *worktree;
1909     struct got_fileindex *fileindex;
1910     got_worktree_checkout_cb progress_cb;
1911     void *progress_arg;
1912     got_worktree_cancel_cb cancel_cb;
1913     void *cancel_arg;
1914     struct got_object_id *commit_id2;
1915 };
1916 
1917 static const struct got_error *
1918 merge_file_cb(void *arg, struct got_blob_object *blob1,
1919     struct got_blob_object *blob2, struct got_object_id *id1,
1920     struct got_object_id *id2, const char *path1, const char *path2,
1921     struct got_repository *repo)
1922 {
1923 	static const struct got_error *err = NULL;
1924 	struct merge_file_cb_arg *a = arg;
1925 	struct got_fileindex_entry *ie;
1926 	char *ondisk_path = NULL;
1927 	struct stat sb;
1928 	unsigned char status;
1929 	int local_changes_subsumed;
1930 
1931 	if (blob1 && blob2) {
1932 		ie = got_fileindex_entry_get(a->fileindex, path2,
1933 		    strlen(path2));
1934 		if (ie == NULL)
1935 			return (*a->progress_cb)(a->progress_arg,
1936 			    GOT_STATUS_MISSING, path2);
1937 
1938 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1939 		    path2) == -1)
1940 			return got_error_from_errno("asprintf");
1941 
1942 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1943 		if (err)
1944 			goto done;
1945 
1946 		if (status == GOT_STATUS_DELETE) {
1947 			err = (*a->progress_cb)(a->progress_arg,
1948 			    GOT_STATUS_MERGE, path2);
1949 			goto done;
1950 		}
1951 		if (status != GOT_STATUS_NO_CHANGE &&
1952 		    status != GOT_STATUS_MODIFY &&
1953 		    status != GOT_STATUS_CONFLICT &&
1954 		    status != GOT_STATUS_ADD) {
1955 			err = (*a->progress_cb)(a->progress_arg, status, path2);
1956 			goto done;
1957 		}
1958 
1959 		err = merge_blob(&local_changes_subsumed, a->worktree, blob1,
1960 		    ondisk_path, path2, sb.st_mode, blob2, a->commit_id2, repo,
1961 		    a->progress_cb, a->progress_arg);
1962 	} else if (blob1) {
1963 		ie = got_fileindex_entry_get(a->fileindex, path1,
1964 		    strlen(path1));
1965 		if (ie == NULL)
1966 			return (*a->progress_cb)(a->progress_arg,
1967 			    GOT_STATUS_MISSING, path2);
1968 
1969 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
1970 		    path1) == -1)
1971 			return got_error_from_errno("asprintf");
1972 
1973 		err = get_file_status(&status, &sb, ie, ondisk_path, repo);
1974 		if (err)
1975 			goto done;
1976 
1977 		switch (status) {
1978 		case GOT_STATUS_NO_CHANGE:
1979 			err = (*a->progress_cb)(a->progress_arg,
1980 			    GOT_STATUS_DELETE, path1);
1981 			if (err)
1982 				goto done;
1983 			err = remove_ondisk_file(a->worktree->root_path, path1);
1984 			if (err)
1985 				goto done;
1986 			if (ie)
1987 				got_fileindex_entry_mark_deleted_from_disk(ie);
1988 			break;
1989 		case GOT_STATUS_DELETE:
1990 		case GOT_STATUS_MISSING:
1991 			err = (*a->progress_cb)(a->progress_arg,
1992 			    GOT_STATUS_DELETE, path1);
1993 			if (err)
1994 				goto done;
1995 			if (ie)
1996 				got_fileindex_entry_mark_deleted_from_disk(ie);
1997 			break;
1998 		case GOT_STATUS_ADD:
1999 		case GOT_STATUS_MODIFY:
2000 		case GOT_STATUS_CONFLICT:
2001 			err = (*a->progress_cb)(a->progress_arg,
2002 			    GOT_STATUS_CANNOT_DELETE, path1);
2003 			if (err)
2004 				goto done;
2005 			break;
2006 		case GOT_STATUS_OBSTRUCTED:
2007 			err = (*a->progress_cb)(a->progress_arg, status, path1);
2008 			if (err)
2009 				goto done;
2010 			break;
2011 		default:
2012 			break;
2013 		}
2014 	} else if (blob2) {
2015 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2016 		    path2) == -1)
2017 			return got_error_from_errno("asprintf");
2018 		ie = got_fileindex_entry_get(a->fileindex, path2,
2019 		    strlen(path2));
2020 		if (ie) {
2021 			err = get_file_status(&status, &sb, ie, ondisk_path,
2022 			    repo);
2023 			if (err)
2024 				goto done;
2025 			if (status != GOT_STATUS_NO_CHANGE &&
2026 			    status != GOT_STATUS_MODIFY &&
2027 			    status != GOT_STATUS_CONFLICT &&
2028 			    status != GOT_STATUS_ADD) {
2029 				err = (*a->progress_cb)(a->progress_arg,
2030 				    status, path2);
2031 				goto done;
2032 			}
2033 			err = merge_blob(&local_changes_subsumed, a->worktree,
2034 			    NULL, ondisk_path, path2, sb.st_mode, blob2,
2035 			    a->commit_id2, repo,
2036 			    a->progress_cb, a->progress_arg);
2037 			if (status == GOT_STATUS_DELETE) {
2038 				err = update_blob_fileindex_entry(a->worktree,
2039 				    a->fileindex, ie, ondisk_path, ie->path,
2040 				    blob2, 0);
2041 				if (err)
2042 					goto done;
2043 			}
2044 		} else {
2045 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
2046 			err = install_blob(a->worktree, ondisk_path, path2,
2047 			    /* XXX get this from parent tree! */
2048 			    GOT_DEFAULT_FILE_MODE,
2049 			    sb.st_mode, blob2, 0, 0, repo,
2050 			    a->progress_cb, a->progress_arg);
2051 			if (err)
2052 				goto done;
2053 			err = got_fileindex_entry_alloc(&ie,
2054 			    ondisk_path, path2, NULL, NULL);
2055 			if (err)
2056 				goto done;
2057 			err = got_fileindex_entry_add(a->fileindex, ie);
2058 			if (err) {
2059 				got_fileindex_entry_free(ie);
2060 				goto done;
2061 			}
2062 		}
2063 	}
2064 done:
2065 	free(ondisk_path);
2066 	return err;
2067 }
2068 
2069 struct check_merge_ok_arg {
2070 	struct got_worktree *worktree;
2071 	struct got_repository *repo;
2072 };
2073 
2074 static const struct got_error *
2075 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
2076 {
2077 	const struct got_error *err = NULL;
2078 	struct check_merge_ok_arg *a = arg;
2079 	unsigned char status;
2080 	struct stat sb;
2081 	char *ondisk_path;
2082 
2083 	/* Reject merges into a work tree with mixed base commits. */
2084 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
2085 	    SHA1_DIGEST_LENGTH))
2086 		return got_error(GOT_ERR_MIXED_COMMITS);
2087 
2088 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
2089 	    == -1)
2090 		return got_error_from_errno("asprintf");
2091 
2092 	/* Reject merges into a work tree with conflicted files. */
2093 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
2094 	if (err)
2095 		return err;
2096 	if (status == GOT_STATUS_CONFLICT)
2097 		return got_error(GOT_ERR_CONFLICTS);
2098 
2099 	return NULL;
2100 }
2101 
2102 static const struct got_error *
2103 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2104     const char *fileindex_path, struct got_object_id *commit_id1,
2105     struct got_object_id *commit_id2, struct got_repository *repo,
2106     got_worktree_checkout_cb progress_cb, void *progress_arg,
2107     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2108 {
2109 	const struct got_error *err = NULL, *sync_err;
2110 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
2111 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
2112 	struct merge_file_cb_arg arg;
2113 
2114 	if (commit_id1) {
2115 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
2116 		    worktree->path_prefix);
2117 		if (err)
2118 			goto done;
2119 
2120 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
2121 		if (err)
2122 			goto done;
2123 	}
2124 
2125 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
2126 	    worktree->path_prefix);
2127 	if (err)
2128 		goto done;
2129 
2130 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
2131 	if (err)
2132 		goto done;
2133 
2134 	arg.worktree = worktree;
2135 	arg.fileindex = fileindex;
2136 	arg.progress_cb = progress_cb;
2137 	arg.progress_arg = progress_arg;
2138 	arg.cancel_cb = cancel_cb;
2139 	arg.cancel_arg = cancel_arg;
2140 	arg.commit_id2 = commit_id2;
2141 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg, 1);
2142 	sync_err = sync_fileindex(fileindex, fileindex_path);
2143 	if (sync_err && err == NULL)
2144 		err = sync_err;
2145 done:
2146 	if (tree1)
2147 		got_object_tree_close(tree1);
2148 	if (tree2)
2149 		got_object_tree_close(tree2);
2150 	return err;
2151 }
2152 
2153 const struct got_error *
2154 got_worktree_merge_files(struct got_worktree *worktree,
2155     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
2156     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2157     void *progress_arg, got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2158 {
2159 	const struct got_error *err, *unlockerr;
2160 	char *fileindex_path = NULL;
2161 	struct got_fileindex *fileindex = NULL;
2162 	struct check_merge_ok_arg mok_arg;
2163 
2164 	err = lock_worktree(worktree, LOCK_EX);
2165 	if (err)
2166 		return err;
2167 
2168 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2169 	if (err)
2170 		goto done;
2171 
2172 	mok_arg.worktree = worktree;
2173 	mok_arg.repo = repo;
2174 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
2175 	    &mok_arg);
2176 	if (err)
2177 		goto done;
2178 
2179 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
2180 	    commit_id2, repo, progress_cb, progress_arg, cancel_cb, cancel_arg);
2181 done:
2182 	if (fileindex)
2183 		got_fileindex_free(fileindex);
2184 	free(fileindex_path);
2185 	unlockerr = lock_worktree(worktree, LOCK_SH);
2186 	if (unlockerr && err == NULL)
2187 		err = unlockerr;
2188 	return err;
2189 }
2190 
2191 struct diff_dir_cb_arg {
2192     struct got_fileindex *fileindex;
2193     struct got_worktree *worktree;
2194     const char *status_path;
2195     size_t status_path_len;
2196     struct got_repository *repo;
2197     got_worktree_status_cb status_cb;
2198     void *status_arg;
2199     got_worktree_cancel_cb cancel_cb;
2200     void *cancel_arg;
2201 };
2202 
2203 static const struct got_error *
2204 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
2205     got_worktree_status_cb status_cb, void *status_arg,
2206     struct got_repository *repo)
2207 {
2208 	const struct got_error *err = NULL;
2209 	unsigned char status = GOT_STATUS_NO_CHANGE;
2210 	unsigned char staged_status = get_staged_status(ie);
2211 	struct stat sb;
2212 	struct got_object_id blob_id, commit_id;
2213 
2214 	err = get_file_status(&status, &sb, ie, abspath, repo);
2215 	if (err == NULL && (status != GOT_STATUS_NO_CHANGE ||
2216 	    staged_status != GOT_STATUS_NO_CHANGE)) {
2217 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2218 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2219 		err = (*status_cb)(status_arg, status, staged_status,
2220 		    ie->path, &blob_id, &commit_id);
2221 	}
2222 	return err;
2223 }
2224 
2225 static const struct got_error *
2226 status_old_new(void *arg, struct got_fileindex_entry *ie,
2227     struct dirent *de, const char *parent_path)
2228 {
2229 	const struct got_error *err = NULL;
2230 	struct diff_dir_cb_arg *a = arg;
2231 	char *abspath;
2232 
2233 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2234 		return got_error(GOT_ERR_CANCELLED);
2235 
2236 	if (got_path_cmp(parent_path, a->status_path,
2237 	    strlen(parent_path), a->status_path_len) != 0 &&
2238 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
2239 		return NULL;
2240 
2241 	if (parent_path[0]) {
2242 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
2243 		    parent_path, de->d_name) == -1)
2244 			return got_error_from_errno("asprintf");
2245 	} else {
2246 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
2247 		    de->d_name) == -1)
2248 			return got_error_from_errno("asprintf");
2249 	}
2250 
2251 	err = report_file_status(ie, abspath, a->status_cb, a->status_arg,
2252 	    a->repo);
2253 	free(abspath);
2254 	return err;
2255 }
2256 
2257 static const struct got_error *
2258 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2259 {
2260 	struct diff_dir_cb_arg *a = arg;
2261 	struct got_object_id blob_id, commit_id;
2262 	unsigned char status;
2263 
2264 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2265 		return got_error(GOT_ERR_CANCELLED);
2266 
2267 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
2268 		return NULL;
2269 
2270 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2271 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
2272 	if (got_fileindex_entry_has_file_on_disk(ie))
2273 		status = GOT_STATUS_MISSING;
2274 	else
2275 		status = GOT_STATUS_DELETE;
2276 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
2277 	    ie->path, &blob_id, &commit_id);
2278 }
2279 
2280 static const struct got_error *
2281 status_new(void *arg, struct dirent *de, const char *parent_path)
2282 {
2283 	const struct got_error *err = NULL;
2284 	struct diff_dir_cb_arg *a = arg;
2285 	char *path = NULL;
2286 
2287 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2288 		return got_error(GOT_ERR_CANCELLED);
2289 
2290 	if (de->d_type == DT_DIR)
2291 		return NULL;
2292 
2293 	/* XXX ignore symlinks for now */
2294 	if (de->d_type == DT_LNK)
2295 		return NULL;
2296 
2297 	if (parent_path[0]) {
2298 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
2299 			return got_error_from_errno("asprintf");
2300 	} else {
2301 		path = de->d_name;
2302 	}
2303 
2304 	if (got_path_is_child(path, a->status_path, a->status_path_len))
2305 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
2306 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL);
2307 	if (parent_path[0])
2308 		free(path);
2309 	return err;
2310 }
2311 
2312 static const struct got_error *
2313 report_single_file_status(const char *path, const char *ondisk_path,
2314 struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
2315 void *status_arg, struct got_repository *repo)
2316 {
2317 	struct got_fileindex_entry *ie;
2318 	struct stat sb;
2319 
2320 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
2321 	if (ie)
2322 		return report_file_status(ie, ondisk_path, status_cb,
2323 		    status_arg, repo);
2324 
2325 	if (lstat(ondisk_path, &sb) == -1) {
2326 		if (errno != ENOENT)
2327 			return got_error_from_errno2("lstat", ondisk_path);
2328 		return NULL;
2329 	}
2330 
2331 	if (S_ISREG(sb.st_mode))
2332 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
2333 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL);
2334 
2335 	return NULL;
2336 }
2337 
2338 static const struct got_error *
2339 worktree_status(struct got_worktree *worktree, const char *path,
2340     struct got_fileindex *fileindex, struct got_repository *repo,
2341     got_worktree_status_cb status_cb, void *status_arg,
2342     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2343 {
2344 	const struct got_error *err = NULL;
2345 	DIR *workdir = NULL;
2346 	struct got_fileindex_diff_dir_cb fdiff_cb;
2347 	struct diff_dir_cb_arg arg;
2348 	char *ondisk_path = NULL;
2349 
2350 	if (asprintf(&ondisk_path, "%s%s%s",
2351 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
2352 		return got_error_from_errno("asprintf");
2353 
2354 	workdir = opendir(ondisk_path);
2355 	if (workdir == NULL) {
2356 		if (errno != ENOTDIR && errno != ENOENT)
2357 			err = got_error_from_errno2("opendir", ondisk_path);
2358 		else
2359 			err = report_single_file_status(path, ondisk_path,
2360 			    fileindex, status_cb, status_arg, repo);
2361 	} else {
2362 		fdiff_cb.diff_old_new = status_old_new;
2363 		fdiff_cb.diff_old = status_old;
2364 		fdiff_cb.diff_new = status_new;
2365 		arg.fileindex = fileindex;
2366 		arg.worktree = worktree;
2367 		arg.status_path = path;
2368 		arg.status_path_len = strlen(path);
2369 		arg.repo = repo;
2370 		arg.status_cb = status_cb;
2371 		arg.status_arg = status_arg;
2372 		arg.cancel_cb = cancel_cb;
2373 		arg.cancel_arg = cancel_arg;
2374 		err = got_fileindex_diff_dir(fileindex, workdir,
2375 		    worktree->root_path, path, repo, &fdiff_cb, &arg);
2376 	}
2377 
2378 	if (workdir)
2379 		closedir(workdir);
2380 	free(ondisk_path);
2381 	return err;
2382 }
2383 
2384 const struct got_error *
2385 got_worktree_status(struct got_worktree *worktree,
2386     struct got_pathlist_head *paths, struct got_repository *repo,
2387     got_worktree_status_cb status_cb, void *status_arg,
2388     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
2389 {
2390 	const struct got_error *err = NULL;
2391 	char *fileindex_path = NULL;
2392 	struct got_fileindex *fileindex = NULL;
2393 	struct got_pathlist_entry *pe;
2394 
2395 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2396 	if (err)
2397 		return err;
2398 
2399 	TAILQ_FOREACH(pe, paths, entry) {
2400 		err = worktree_status(worktree, pe->path, fileindex, repo,
2401 			status_cb, status_arg, cancel_cb, cancel_arg);
2402 		if (err)
2403 			break;
2404 	}
2405 	free(fileindex_path);
2406 	got_fileindex_free(fileindex);
2407 	return err;
2408 }
2409 
2410 const struct got_error *
2411 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
2412     const char *arg)
2413 {
2414 	const struct got_error *err = NULL;
2415 	char *resolved, *cwd = NULL, *path = NULL;
2416 	size_t len;
2417 
2418 	*wt_path = NULL;
2419 
2420 	resolved = realpath(arg, NULL);
2421 	if (resolved == NULL) {
2422 		if (errno != ENOENT)
2423 			return got_error_from_errno2("realpath", arg);
2424 		cwd = getcwd(NULL, 0);
2425 		if (cwd == NULL)
2426 			return got_error_from_errno("getcwd");
2427 		if (asprintf(&resolved, "%s/%s", cwd, arg) == -1) {
2428 			err = got_error_from_errno("asprintf");
2429 			goto done;
2430 		}
2431 	}
2432 
2433 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
2434 	    strlen(got_worktree_get_root_path(worktree)))) {
2435 		err = got_error(GOT_ERR_BAD_PATH);
2436 		goto done;
2437 	}
2438 
2439 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
2440 		err = got_path_skip_common_ancestor(&path,
2441 		    got_worktree_get_root_path(worktree), resolved);
2442 		if (err)
2443 			goto done;
2444 	} else {
2445 		path = strdup("");
2446 		if (path == NULL) {
2447 			err = got_error_from_errno("strdup");
2448 			goto done;
2449 		}
2450 	}
2451 
2452 	/* XXX status walk can't deal with trailing slash! */
2453 	len = strlen(path);
2454 	while (len > 0 && path[len - 1] == '/') {
2455 		path[len - 1] = '\0';
2456 		len--;
2457 	}
2458 done:
2459 	free(resolved);
2460 	free(cwd);
2461 	if (err == NULL)
2462 		*wt_path = path;
2463 	else
2464 		free(path);
2465 	return err;
2466 }
2467 
2468 static const struct got_error *
2469 schedule_addition(const char *ondisk_path, struct got_fileindex *fileindex,
2470     const char *relpath, got_worktree_status_cb status_cb, void *status_arg,
2471     struct got_repository *repo)
2472 {
2473 	const struct got_error *err = NULL;
2474 	struct got_fileindex_entry *ie;
2475 
2476 	/* Re-adding an existing entry is a no-op. */
2477 	if (got_fileindex_entry_get(fileindex, relpath, strlen(relpath)))
2478 		return NULL;
2479 
2480 	err = got_fileindex_entry_alloc(&ie, ondisk_path, relpath, NULL, NULL);
2481 	if (err)
2482 		return err;
2483 
2484 	err = got_fileindex_entry_add(fileindex, ie);
2485 	if (err) {
2486 		got_fileindex_entry_free(ie);
2487 		return err;
2488 	}
2489 
2490 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2491 }
2492 
2493 const struct got_error *
2494 got_worktree_schedule_add(struct got_worktree *worktree,
2495     struct got_pathlist_head *ondisk_paths,
2496     got_worktree_status_cb status_cb, void *status_arg,
2497     struct got_repository *repo)
2498 {
2499 	struct got_fileindex *fileindex = NULL;
2500 	char *fileindex_path = NULL;
2501 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2502 	struct got_pathlist_entry *pe;
2503 
2504 	err = lock_worktree(worktree, LOCK_EX);
2505 	if (err)
2506 		return err;
2507 
2508 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2509 	if (err)
2510 		goto done;
2511 
2512 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2513 		char *relpath;
2514 		err = got_path_skip_common_ancestor(&relpath,
2515 		    got_worktree_get_root_path(worktree), pe->path);
2516 		if (err)
2517 			break;
2518 		err = schedule_addition(pe->path, fileindex, relpath,
2519 		    status_cb, status_arg, repo);
2520 		free(relpath);
2521 		if (err)
2522 			break;
2523 	}
2524 	sync_err = sync_fileindex(fileindex, fileindex_path);
2525 	if (sync_err && err == NULL)
2526 		err = sync_err;
2527 done:
2528 	free(fileindex_path);
2529 	if (fileindex)
2530 		got_fileindex_free(fileindex);
2531 	unlockerr = lock_worktree(worktree, LOCK_SH);
2532 	if (unlockerr && err == NULL)
2533 		err = unlockerr;
2534 	return err;
2535 }
2536 
2537 static const struct got_error *
2538 schedule_for_deletion(const char *ondisk_path, struct got_fileindex *fileindex,
2539     const char *relpath, int delete_local_mods,
2540     got_worktree_status_cb status_cb, void *status_arg,
2541     struct got_repository *repo)
2542 {
2543 	const struct got_error *err = NULL;
2544 	struct got_fileindex_entry *ie = NULL;
2545 	unsigned char status;
2546 	struct stat sb;
2547 
2548 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2549 	if (ie == NULL)
2550 		return got_error(GOT_ERR_BAD_PATH);
2551 
2552 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2553 	if (err)
2554 		return err;
2555 
2556 	if (status != GOT_STATUS_NO_CHANGE) {
2557 		if (status == GOT_STATUS_DELETE)
2558 			return NULL;
2559 		if (status != GOT_STATUS_MODIFY)
2560 			return got_error(GOT_ERR_FILE_STATUS);
2561 		if (!delete_local_mods)
2562 			return got_error(GOT_ERR_FILE_MODIFIED);
2563 	}
2564 
2565 	if (unlink(ondisk_path) != 0)
2566 		return got_error_from_errno2("unlink", ondisk_path);
2567 
2568 	got_fileindex_entry_mark_deleted_from_disk(ie);
2569 	return report_file_status(ie, ondisk_path, status_cb, status_arg, repo);
2570 }
2571 
2572 const struct got_error *
2573 got_worktree_schedule_delete(struct got_worktree *worktree,
2574     struct got_pathlist_head *ondisk_paths, int delete_local_mods,
2575     got_worktree_status_cb status_cb, void *status_arg,
2576     struct got_repository *repo)
2577 {
2578 	struct got_fileindex *fileindex = NULL;
2579 	char *fileindex_path = NULL;
2580 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2581 	struct got_pathlist_entry *pe;
2582 
2583 	err = lock_worktree(worktree, LOCK_EX);
2584 	if (err)
2585 		return err;
2586 
2587 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2588 	if (err)
2589 		goto done;
2590 
2591 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2592 		char *relpath;
2593 		err = got_path_skip_common_ancestor(&relpath,
2594 		    got_worktree_get_root_path(worktree), pe->path);
2595 		if (err)
2596 			break;
2597 		err = schedule_for_deletion(pe->path, fileindex, relpath,
2598 		    delete_local_mods, status_cb, status_arg, repo);
2599 		free(relpath);
2600 		if (err)
2601 			break;
2602 	}
2603 	sync_err = sync_fileindex(fileindex, fileindex_path);
2604 	if (sync_err && err == NULL)
2605 		err = sync_err;
2606 done:
2607 	free(fileindex_path);
2608 	if (fileindex)
2609 		got_fileindex_free(fileindex);
2610 	unlockerr = lock_worktree(worktree, LOCK_SH);
2611 	if (unlockerr && err == NULL)
2612 		err = unlockerr;
2613 	return err;
2614 }
2615 
2616 static const struct got_error *
2617 revert_file(struct got_worktree *worktree, struct got_fileindex *fileindex,
2618     const char *ondisk_path,
2619     got_worktree_checkout_cb progress_cb, void *progress_arg,
2620     struct got_repository *repo)
2621 {
2622 	const struct got_error *err = NULL;
2623 	char *relpath = NULL, *parent_path = NULL;
2624 	struct got_fileindex_entry *ie;
2625 	struct got_tree_object *tree = NULL;
2626 	struct got_object_id *tree_id = NULL;
2627 	const struct got_tree_entry *te;
2628 	char *tree_path = NULL, *te_name;
2629 	struct got_blob_object *blob = NULL;
2630 	unsigned char status;
2631 	struct stat sb;
2632 
2633 	err = got_path_skip_common_ancestor(&relpath,
2634 	    got_worktree_get_root_path(worktree), ondisk_path);
2635 	if (err)
2636 		goto done;
2637 
2638 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
2639 	if (ie == NULL) {
2640 		err = got_error(GOT_ERR_BAD_PATH);
2641 		goto done;
2642 	}
2643 
2644 	/* Construct in-repository path of tree which contains this blob. */
2645 	err = got_path_dirname(&parent_path, ie->path);
2646 	if (err) {
2647 		if (err->code != GOT_ERR_BAD_PATH)
2648 			goto done;
2649 		parent_path = strdup("/");
2650 		if (parent_path == NULL) {
2651 			err = got_error_from_errno("strdup");
2652 			goto done;
2653 		}
2654 	}
2655 	if (got_path_is_root_dir(worktree->path_prefix)) {
2656 		tree_path = strdup(parent_path);
2657 		if (tree_path == NULL) {
2658 			err = got_error_from_errno("strdup");
2659 			goto done;
2660 		}
2661 	} else {
2662 		if (got_path_is_root_dir(parent_path)) {
2663 			tree_path = strdup(worktree->path_prefix);
2664 			if (tree_path == NULL) {
2665 				err = got_error_from_errno("strdup");
2666 				goto done;
2667 			}
2668 		} else {
2669 			if (asprintf(&tree_path, "%s/%s",
2670 			    worktree->path_prefix, parent_path) == -1) {
2671 				err = got_error_from_errno("asprintf");
2672 				goto done;
2673 			}
2674 		}
2675 	}
2676 
2677 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
2678 	if (err)
2679 		goto done;
2680 	if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
2681 		sb.st_mode = got_fileindex_perms_to_st(ie);
2682 
2683 	err = got_object_id_by_path(&tree_id, repo, worktree->base_commit_id,
2684 	    tree_path);
2685 	if (err) {
2686 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
2687 		    status == GOT_STATUS_ADD))
2688 			goto done;
2689 	} else {
2690 		err = got_object_open_as_tree(&tree, repo, tree_id);
2691 		if (err)
2692 			goto done;
2693 
2694 		te_name = basename(ie->path);
2695 		if (te_name == NULL) {
2696 			err = got_error_from_errno2("basename", ie->path);
2697 			goto done;
2698 		}
2699 
2700 		te = got_object_tree_find_entry(tree, te_name);
2701 		if (te == NULL && status != GOT_STATUS_ADD) {
2702 			err = got_error(GOT_ERR_NO_TREE_ENTRY);
2703 			goto done;
2704 		}
2705 	}
2706 
2707 	switch (status) {
2708 	case GOT_STATUS_ADD:
2709 		err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT, ie->path);
2710 		if (err)
2711 			goto done;
2712 		got_fileindex_entry_remove(fileindex, ie);
2713 		break;
2714 	case GOT_STATUS_DELETE:
2715 	case GOT_STATUS_MODIFY:
2716 	case GOT_STATUS_CONFLICT:
2717 	case GOT_STATUS_MISSING: {
2718 		struct got_object_id id;
2719 		memcpy(id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2720 		err = got_object_open_as_blob(&blob, repo, &id, 8192);
2721 		if (err)
2722 			goto done;
2723 		err = install_blob(worktree, ondisk_path, ie->path,
2724 		    te->mode, sb.st_mode, blob, 0, 1, repo, progress_cb,
2725 		    progress_arg);
2726 		if (err)
2727 			goto done;
2728 		if (status == GOT_STATUS_DELETE) {
2729 			err = update_blob_fileindex_entry(worktree,
2730 			    fileindex, ie, ondisk_path, ie->path, blob, 1);
2731 			if (err)
2732 				goto done;
2733 		}
2734 		break;
2735 	}
2736 	default:
2737 			goto done;
2738 	}
2739 done:
2740 	free(relpath);
2741 	free(parent_path);
2742 	free(tree_path);
2743 	if (blob)
2744 		got_object_blob_close(blob);
2745 	if (tree)
2746 		got_object_tree_close(tree);
2747 	free(tree_id);
2748 	return err;
2749 }
2750 
2751 const struct got_error *
2752 got_worktree_revert(struct got_worktree *worktree,
2753     struct got_pathlist_head *ondisk_paths,
2754     got_worktree_checkout_cb progress_cb, void *progress_arg,
2755     struct got_repository *repo)
2756 {
2757 	struct got_fileindex *fileindex = NULL;
2758 	char *fileindex_path = NULL;
2759 	const struct got_error *err = NULL, *unlockerr = NULL;
2760 	const struct got_error *sync_err = NULL;
2761 	struct got_pathlist_entry *pe;
2762 
2763 	err = lock_worktree(worktree, LOCK_EX);
2764 	if (err)
2765 		return err;
2766 
2767 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2768 	if (err)
2769 		goto done;
2770 
2771 	TAILQ_FOREACH(pe, ondisk_paths, entry) {
2772 		err = revert_file(worktree, fileindex, pe->path,
2773 		    progress_cb, progress_arg, repo);
2774 		if (err)
2775 			break;
2776 	}
2777 	sync_err = sync_fileindex(fileindex, fileindex_path);
2778 	if (sync_err && err == NULL)
2779 		err = sync_err;
2780 done:
2781 	free(fileindex_path);
2782 	if (fileindex)
2783 		got_fileindex_free(fileindex);
2784 	unlockerr = lock_worktree(worktree, LOCK_SH);
2785 	if (unlockerr && err == NULL)
2786 		err = unlockerr;
2787 	return err;
2788 }
2789 
2790 static void
2791 free_commitable(struct got_commitable *ct)
2792 {
2793 	free(ct->path);
2794 	free(ct->in_repo_path);
2795 	free(ct->ondisk_path);
2796 	free(ct->blob_id);
2797 	free(ct->base_blob_id);
2798 	free(ct->base_commit_id);
2799 	free(ct);
2800 }
2801 
2802 struct collect_commitables_arg {
2803 	struct got_pathlist_head *commitable_paths;
2804 	struct got_repository *repo;
2805 	struct got_worktree *worktree;
2806 };
2807 
2808 static const struct got_error *
2809 collect_commitables(void *arg, unsigned char status,
2810     unsigned char staged_status, const char *relpath,
2811     struct got_object_id *blob_id, struct got_object_id *commit_id)
2812 {
2813 	struct collect_commitables_arg *a = arg;
2814 	const struct got_error *err = NULL;
2815 	struct got_commitable *ct = NULL;
2816 	struct got_pathlist_entry *new = NULL;
2817 	char *parent_path = NULL, *path = NULL;
2818 	struct stat sb;
2819 
2820 	if (status == GOT_STATUS_CONFLICT)
2821 		return got_error(GOT_ERR_COMMIT_CONFLICT);
2822 
2823 	if (status != GOT_STATUS_MODIFY && status != GOT_STATUS_ADD &&
2824 	    status != GOT_STATUS_DELETE)
2825 		return NULL;
2826 
2827 	if (asprintf(&path, "/%s", relpath) == -1) {
2828 		err = got_error_from_errno("asprintf");
2829 		goto done;
2830 	}
2831 	if (strcmp(path, "/") == 0) {
2832 		parent_path = strdup("");
2833 		if (parent_path == NULL)
2834 			return got_error_from_errno("strdup");
2835 	} else {
2836 		err = got_path_dirname(&parent_path, path);
2837 		if (err)
2838 			return err;
2839 	}
2840 
2841 	ct = calloc(1, sizeof(*ct));
2842 	if (ct == NULL) {
2843 		err = got_error_from_errno("calloc");
2844 		goto done;
2845 	}
2846 
2847 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
2848 	    relpath) == -1) {
2849 		err = got_error_from_errno("asprintf");
2850 		goto done;
2851 	}
2852 	if (status == GOT_STATUS_DELETE) {
2853 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
2854 	} else {
2855 		if (lstat(ct->ondisk_path, &sb) != 0) {
2856 			err = got_error_from_errno2("lstat", ct->ondisk_path);
2857 			goto done;
2858 		}
2859 		ct->mode = sb.st_mode;
2860 	}
2861 
2862 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
2863 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
2864 	    relpath) == -1) {
2865 		err = got_error_from_errno("asprintf");
2866 		goto done;
2867 	}
2868 
2869 	ct->status = status;
2870 	ct->blob_id = NULL; /* will be filled in when blob gets created */
2871 	if (ct->status != GOT_STATUS_ADD) {
2872 		ct->base_blob_id = got_object_id_dup(blob_id);
2873 		if (ct->base_blob_id == NULL) {
2874 			err = got_error_from_errno("got_object_id_dup");
2875 			goto done;
2876 		}
2877 		ct->base_commit_id = got_object_id_dup(commit_id);
2878 		if (ct->base_commit_id == NULL) {
2879 			err = got_error_from_errno("got_object_id_dup");
2880 			goto done;
2881 		}
2882 	}
2883 	ct->path = strdup(path);
2884 	if (ct->path == NULL) {
2885 		err = got_error_from_errno("strdup");
2886 		goto done;
2887 	}
2888 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
2889 done:
2890 	if (ct && (err || new == NULL))
2891 		free_commitable(ct);
2892 	free(parent_path);
2893 	free(path);
2894 	return err;
2895 }
2896 
2897 static const struct got_error *write_tree(struct got_object_id **,
2898     struct got_tree_object *, const char *, struct got_pathlist_head *,
2899     got_worktree_status_cb status_cb, void *status_arg,
2900     struct got_repository *);
2901 
2902 static const struct got_error *
2903 write_subtree(struct got_object_id **new_subtree_id,
2904     struct got_tree_entry *te, const char *parent_path,
2905     struct got_pathlist_head *commitable_paths,
2906     got_worktree_status_cb status_cb, void *status_arg,
2907     struct got_repository *repo)
2908 {
2909 	const struct got_error *err = NULL;
2910 	struct got_tree_object *subtree;
2911 	char *subpath;
2912 
2913 	if (asprintf(&subpath, "%s%s%s", parent_path,
2914 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
2915 		return got_error_from_errno("asprintf");
2916 
2917 	err = got_object_open_as_tree(&subtree, repo, te->id);
2918 	if (err)
2919 		return err;
2920 
2921 	err = write_tree(new_subtree_id, subtree, subpath, commitable_paths,
2922 	    status_cb, status_arg, repo);
2923 	got_object_tree_close(subtree);
2924 	free(subpath);
2925 	return err;
2926 }
2927 
2928 static const struct got_error *
2929 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
2930 {
2931 	const struct got_error *err = NULL;
2932 	char *ct_parent_path = NULL;
2933 
2934 	*match = 0;
2935 
2936 	if (strchr(ct->in_repo_path, '/') == NULL) {
2937 		*match = got_path_is_root_dir(path);
2938 		return NULL;
2939 	}
2940 
2941 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
2942 	if (err)
2943 		return err;
2944 	*match = (strcmp(path, ct_parent_path) == 0);
2945 	free(ct_parent_path);
2946 	return err;
2947 }
2948 
2949 static mode_t
2950 get_ct_file_mode(struct got_commitable *ct)
2951 {
2952 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
2953 }
2954 
2955 static const struct got_error *
2956 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
2957     struct got_tree_entry *te, struct got_commitable *ct)
2958 {
2959 	const struct got_error *err = NULL;
2960 
2961 	*new_te = NULL;
2962 
2963 	err = got_object_tree_entry_dup(new_te, te);
2964 	if (err)
2965 		goto done;
2966 
2967 	(*new_te)->mode = get_ct_file_mode(ct);
2968 
2969 	free((*new_te)->id);
2970 	(*new_te)->id = got_object_id_dup(ct->blob_id);
2971 	if ((*new_te)->id == NULL) {
2972 		err = got_error_from_errno("got_object_id_dup");
2973 		goto done;
2974 	}
2975 done:
2976 	if (err && *new_te) {
2977 		got_object_tree_entry_close(*new_te);
2978 		*new_te = NULL;
2979 	}
2980 	return err;
2981 }
2982 
2983 static const struct got_error *
2984 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
2985     struct got_commitable *ct)
2986 {
2987 	const struct got_error *err = NULL;
2988 	char *ct_name;
2989 
2990 	 *new_te = NULL;
2991 
2992 	*new_te = calloc(1, sizeof(**new_te));
2993 	if (*new_te == NULL)
2994 		return got_error_from_errno("calloc");
2995 
2996 	ct_name = basename(ct->path);
2997 	if (ct_name == NULL) {
2998 		err = got_error_from_errno2("basename", ct->path);
2999 		goto done;
3000 	}
3001 	(*new_te)->name = strdup(ct_name);
3002 	if ((*new_te)->name == NULL) {
3003 		err = got_error_from_errno("strdup");
3004 		goto done;
3005 	}
3006 
3007 	(*new_te)->mode = get_ct_file_mode(ct);
3008 
3009 	(*new_te)->id = got_object_id_dup(ct->blob_id);
3010 	if ((*new_te)->id == NULL) {
3011 		err = got_error_from_errno("got_object_id_dup");
3012 		goto done;
3013 	}
3014 done:
3015 	if (err && *new_te) {
3016 		got_object_tree_entry_close(*new_te);
3017 		*new_te = NULL;
3018 	}
3019 	return err;
3020 }
3021 
3022 static const struct got_error *
3023 insert_tree_entry(struct got_tree_entry *new_te,
3024     struct got_pathlist_head *paths)
3025 {
3026 	const struct got_error *err = NULL;
3027 	struct got_pathlist_entry *new_pe;
3028 
3029 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
3030 	if (err)
3031 		return err;
3032 	if (new_pe == NULL)
3033 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
3034 	return NULL;
3035 }
3036 
3037 static const struct got_error *
3038 report_ct_status(struct got_commitable *ct,
3039     got_worktree_status_cb status_cb, void *status_arg)
3040 {
3041 	const char *ct_path = ct->path;
3042 	while (ct_path[0] == '/')
3043 		ct_path++;
3044 	return (*status_cb)(status_arg, ct->status, GOT_STATUS_NO_CHANGE,
3045 	    ct_path, ct->blob_id, NULL);
3046 }
3047 
3048 static const struct got_error *
3049 match_modified_subtree(int *modified, struct got_tree_entry *te,
3050     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
3051 {
3052 	const struct got_error *err = NULL;
3053 	struct got_pathlist_entry *pe;
3054 	char *te_path;
3055 
3056 	*modified = 0;
3057 
3058 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
3059 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
3060 	    te->name) == -1)
3061 		return got_error_from_errno("asprintf");
3062 
3063 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3064 		struct got_commitable *ct = pe->data;
3065 		*modified = got_path_is_child(ct->in_repo_path, te_path,
3066 		    strlen(te_path));
3067 		 if (*modified)
3068 			break;
3069 	}
3070 
3071 	free(te_path);
3072 	return err;
3073 }
3074 
3075 static const struct got_error *
3076 match_deleted_or_modified_ct(struct got_commitable **ctp,
3077     struct got_tree_entry *te, const char *base_tree_path,
3078     struct got_pathlist_head *commitable_paths)
3079 {
3080 	const struct got_error *err = NULL;
3081 	struct got_pathlist_entry *pe;
3082 
3083 	*ctp = NULL;
3084 
3085 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3086 		struct got_commitable *ct = pe->data;
3087 		char *ct_name = NULL;
3088 		int path_matches;
3089 
3090 		if (ct->status != GOT_STATUS_MODIFY &&
3091 		    ct->status != GOT_STATUS_DELETE)
3092 			continue;
3093 
3094 		if (got_object_id_cmp(ct->base_blob_id, te->id) != 0)
3095 			continue;
3096 
3097 		 err = match_ct_parent_path(&path_matches, ct, base_tree_path);
3098 		 if (err)
3099 			return err;
3100 		if (!path_matches)
3101 			continue;
3102 
3103 		ct_name = basename(pe->path);
3104 		if (ct_name == NULL)
3105 			return got_error_from_errno2("basename", pe->path);
3106 
3107 		if (strcmp(te->name, ct_name) != 0)
3108 			continue;
3109 
3110 		*ctp = ct;
3111 		break;
3112 	}
3113 
3114 	return err;
3115 }
3116 
3117 static const struct got_error *
3118 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
3119     const char *child_path, const char *path_base_tree,
3120     struct got_pathlist_head *commitable_paths,
3121     got_worktree_status_cb status_cb, void *status_arg,
3122     struct got_repository *repo)
3123 {
3124 	const struct got_error *err = NULL;
3125 	struct got_tree_entry *new_te;
3126 	char *subtree_path;
3127 
3128 	*new_tep = NULL;
3129 
3130 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
3131 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
3132 	    child_path) == -1)
3133 		return got_error_from_errno("asprintf");
3134 
3135 	new_te = calloc(1, sizeof(*new_te));
3136 	new_te->mode = S_IFDIR;
3137 	new_te->name = strdup(child_path);
3138 	if (new_te->name == NULL) {
3139 		err = got_error_from_errno("strdup");
3140 		got_object_tree_entry_close(new_te);
3141 		goto done;
3142 	}
3143 	err = write_tree(&new_te->id, NULL, subtree_path,
3144 	    commitable_paths, status_cb, status_arg, repo);
3145 	if (err) {
3146 		got_object_tree_entry_close(new_te);
3147 		goto done;
3148 	}
3149 done:
3150 	free(subtree_path);
3151 	if (err == NULL)
3152 		*new_tep = new_te;
3153 	return err;
3154 }
3155 
3156 static const struct got_error *
3157 write_tree(struct got_object_id **new_tree_id,
3158     struct got_tree_object *base_tree, const char *path_base_tree,
3159     struct got_pathlist_head *commitable_paths,
3160     got_worktree_status_cb status_cb, void *status_arg,
3161     struct got_repository *repo)
3162 {
3163 	const struct got_error *err = NULL;
3164 	const struct got_tree_entries *base_entries = NULL;
3165 	struct got_pathlist_head paths;
3166 	struct got_tree_entries new_tree_entries;
3167 	struct got_tree_entry *te, *new_te = NULL;
3168 	struct got_pathlist_entry *pe;
3169 
3170 	TAILQ_INIT(&paths);
3171 	new_tree_entries.nentries = 0;
3172 	SIMPLEQ_INIT(&new_tree_entries.head);
3173 
3174 	/* Insert, and recurse into, newly added entries first. */
3175 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3176 		struct got_commitable *ct = pe->data;
3177 		char *child_path = NULL, *slash;
3178 
3179 		if (ct->status != GOT_STATUS_ADD ||
3180 		    (ct->flags & GOT_COMMITABLE_ADDED))
3181 			continue;
3182 
3183 		 if (!got_path_is_child(pe->path, path_base_tree,
3184 		     strlen(path_base_tree)))
3185 			continue;
3186 
3187 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
3188 		    pe->path);
3189 		if (err)
3190 			goto done;
3191 
3192 		slash = strchr(child_path, '/');
3193 		if (slash == NULL) {
3194 			err = alloc_added_blob_tree_entry(&new_te, ct);
3195 			if (err)
3196 				goto done;
3197 			err = report_ct_status(ct, status_cb, status_arg);
3198 			if (err)
3199 				goto done;
3200 			ct->flags |= GOT_COMMITABLE_ADDED;
3201 			err = insert_tree_entry(new_te, &paths);
3202 			if (err)
3203 				goto done;
3204 		} else {
3205 			*slash = '\0'; /* trim trailing path components */
3206 			if (base_tree == NULL ||
3207 			    got_object_tree_find_entry(base_tree, child_path)
3208 			    == NULL) {
3209 				err = make_subtree_for_added_blob(&new_te,
3210 				    child_path, path_base_tree,
3211 				    commitable_paths, status_cb, status_arg,
3212 				    repo);
3213 				if (err)
3214 					goto done;
3215 				err = insert_tree_entry(new_te, &paths);
3216 				if (err)
3217 					goto done;
3218 			}
3219 		}
3220 	}
3221 
3222 	if (base_tree) {
3223 		/* Handle modified and deleted entries. */
3224 		base_entries = got_object_tree_get_entries(base_tree);
3225 		SIMPLEQ_FOREACH(te, &base_entries->head, entry) {
3226 			struct got_commitable *ct = NULL;
3227 
3228 			if (S_ISDIR(te->mode)) {
3229 				int modified;
3230 				err = got_object_tree_entry_dup(&new_te, te);
3231 				if (err)
3232 					goto done;
3233 				err = match_modified_subtree(&modified, te,
3234 				    path_base_tree, commitable_paths);
3235 				if (err)
3236 					goto done;
3237 				/* Avoid recursion into unmodified subtrees. */
3238 				if (modified) {
3239 					free(new_te->id);
3240 					err = write_subtree(&new_te->id, te,
3241 					    path_base_tree, commitable_paths,
3242 					    status_cb, status_arg, repo);
3243 					if (err)
3244 						goto done;
3245 				}
3246 				err = insert_tree_entry(new_te, &paths);
3247 				if (err)
3248 					goto done;
3249 				continue;
3250 			}
3251 
3252 			err = match_deleted_or_modified_ct(&ct, te,
3253 			    path_base_tree, commitable_paths);
3254 			if (ct) {
3255 				/* NB: Deleted entries get dropped here. */
3256 				if (ct->status == GOT_STATUS_MODIFY) {
3257 					err = alloc_modified_blob_tree_entry(
3258 					    &new_te, te, ct);
3259 					if (err)
3260 						goto done;
3261 					err = insert_tree_entry(new_te, &paths);
3262 					if (err)
3263 						goto done;
3264 				}
3265 				err = report_ct_status(ct, status_cb,
3266 				    status_arg);
3267 				if (err)
3268 					goto done;
3269 			} else {
3270 				/* Entry is unchanged; just copy it. */
3271 				err = got_object_tree_entry_dup(&new_te, te);
3272 				if (err)
3273 					goto done;
3274 				err = insert_tree_entry(new_te, &paths);
3275 				if (err)
3276 					goto done;
3277 			}
3278 		}
3279 	}
3280 
3281 	/* Write new list of entries; deleted entries have been dropped. */
3282 	TAILQ_FOREACH(pe, &paths, entry) {
3283 		struct got_tree_entry *te = pe->data;
3284 		new_tree_entries.nentries++;
3285 		SIMPLEQ_INSERT_TAIL(&new_tree_entries.head, te, entry);
3286 	}
3287 	err = got_object_tree_create(new_tree_id, &new_tree_entries, repo);
3288 done:
3289 	got_object_tree_entries_close(&new_tree_entries);
3290 	got_pathlist_free(&paths);
3291 	return err;
3292 }
3293 
3294 static const struct got_error *
3295 update_fileindex_after_commit(struct got_pathlist_head *commitable_paths,
3296     struct got_object_id *new_base_commit_id, struct got_fileindex *fileindex)
3297 {
3298 	const struct got_error *err = NULL;
3299 	struct got_pathlist_entry *pe;
3300 
3301 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3302 		struct got_fileindex_entry *ie;
3303 		struct got_commitable *ct = pe->data;
3304 
3305 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
3306 		if (ie) {
3307 			if (ct->status == GOT_STATUS_DELETE) {
3308 				got_fileindex_entry_remove(fileindex, ie);
3309 				got_fileindex_entry_free(ie);
3310 			} else
3311 				err = got_fileindex_entry_update(ie,
3312 				    ct->ondisk_path, ct->blob_id->sha1,
3313 				    new_base_commit_id->sha1, 1);
3314 		} else {
3315 			err = got_fileindex_entry_alloc(&ie,
3316 			    ct->ondisk_path, pe->path, ct->blob_id->sha1,
3317 			    new_base_commit_id->sha1);
3318 			if (err)
3319 				break;
3320 			err = got_fileindex_entry_add(fileindex, ie);
3321 			if (err)
3322 				break;
3323 		}
3324 	}
3325 	return err;
3326 }
3327 
3328 static const struct got_error *
3329 check_ct_out_of_date(struct got_commitable *ct, struct got_repository *repo,
3330 	struct got_object_id *head_commit_id)
3331 {
3332 	const struct got_error *err = NULL;
3333 	struct got_object_id *id = NULL;
3334 	struct got_commit_object *commit = NULL;
3335 	const char *ct_path = ct->in_repo_path;
3336 
3337 	while (ct_path[0] == '/')
3338 		ct_path++;
3339 
3340 	if (ct->status != GOT_STATUS_ADD) {
3341 		/* Trivial case: base commit == head commit */
3342 		if (got_object_id_cmp(ct->base_commit_id, head_commit_id) == 0)
3343 			return NULL;
3344 		/*
3345 		 * Ensure file content which local changes were based
3346 		 * on matches file content in the branch head.
3347 		 */
3348 		err = got_object_id_by_path(&id, repo, head_commit_id, ct_path);
3349 		if (err) {
3350 			if (err->code != GOT_ERR_NO_TREE_ENTRY)
3351 				goto done;
3352 			err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3353 			goto done;
3354 		} else if (got_object_id_cmp(id, ct->base_blob_id) != 0)
3355 			err = got_error(GOT_ERR_COMMIT_OUT_OF_DATE);
3356 	} else {
3357 		/* Require that added files don't exist in the branch head. */
3358 		err = got_object_id_by_path(&id, repo, head_commit_id, ct_path);
3359 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3360 			goto done;
3361 		err = id ? got_error(GOT_ERR_COMMIT_OUT_OF_DATE) : NULL;
3362 	}
3363 done:
3364 	if (commit)
3365 		got_object_commit_close(commit);
3366 	free(id);
3367 	return err;
3368 }
3369 
3370 const struct got_error *
3371 commit_worktree(struct got_object_id **new_commit_id,
3372     struct got_pathlist_head *commitable_paths,
3373     struct got_object_id *head_commit_id, struct got_worktree *worktree,
3374     const char *author, const char *committer,
3375     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3376     got_worktree_status_cb status_cb, void *status_arg,
3377     struct got_repository *repo)
3378 {
3379 	const struct got_error *err = NULL, *unlockerr = NULL;
3380 	struct got_pathlist_entry *pe;
3381 	const char *head_ref_name = NULL;
3382 	struct got_commit_object *head_commit = NULL;
3383 	struct got_reference *head_ref2 = NULL;
3384 	struct got_object_id *head_commit_id2 = NULL;
3385 	struct got_tree_object *head_tree = NULL;
3386 	struct got_object_id *new_tree_id = NULL;
3387 	struct got_object_id_queue parent_ids;
3388 	struct got_object_qid *pid = NULL;
3389 	char *logmsg = NULL;
3390 
3391 	*new_commit_id = NULL;
3392 
3393 	SIMPLEQ_INIT(&parent_ids);
3394 
3395 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
3396 	if (err)
3397 		goto done;
3398 
3399 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
3400 	if (err)
3401 		goto done;
3402 
3403 	if (commit_msg_cb != NULL) {
3404 		err = commit_msg_cb(commitable_paths, &logmsg, commit_arg);
3405 		if (err)
3406 			goto done;
3407 	}
3408 
3409 	if (logmsg == NULL || strlen(logmsg) == 0) {
3410 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
3411 		goto done;
3412 	}
3413 
3414 	/* Create blobs from added and modified files and record their IDs. */
3415 	TAILQ_FOREACH(pe, commitable_paths, entry) {
3416 		struct got_commitable *ct = pe->data;
3417 		char *ondisk_path;
3418 
3419 		if (ct->status != GOT_STATUS_ADD &&
3420 		    ct->status != GOT_STATUS_MODIFY)
3421 			continue;
3422 
3423 		if (asprintf(&ondisk_path, "%s/%s",
3424 		    worktree->root_path, pe->path) == -1) {
3425 			err = got_error_from_errno("asprintf");
3426 			goto done;
3427 		}
3428 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
3429 		free(ondisk_path);
3430 		if (err)
3431 			goto done;
3432 	}
3433 
3434 	/* Recursively write new tree objects. */
3435 	err = write_tree(&new_tree_id, head_tree, "/", commitable_paths,
3436 	    status_cb, status_arg, repo);
3437 	if (err)
3438 		goto done;
3439 
3440 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
3441 	if (err)
3442 		goto done;
3443 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
3444 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
3445 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
3446 	got_object_qid_free(pid);
3447 	if (logmsg != NULL)
3448 		free(logmsg);
3449 	if (err)
3450 		goto done;
3451 
3452 	/* Check if a concurrent commit to our branch has occurred. */
3453 	head_ref_name = got_worktree_get_head_ref_name(worktree);
3454 	if (head_ref_name == NULL) {
3455 		err = got_error_from_errno("got_worktree_get_head_ref_name");
3456 		goto done;
3457 	}
3458 	/* Lock the reference here to prevent concurrent modification. */
3459 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
3460 	if (err)
3461 		goto done;
3462 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
3463 	if (err)
3464 		goto done;
3465 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
3466 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
3467 		goto done;
3468 	}
3469 	/* Update branch head in repository. */
3470 	err = got_ref_change_ref(head_ref2, *new_commit_id);
3471 	if (err)
3472 		goto done;
3473 	err = got_ref_write(head_ref2, repo);
3474 	if (err)
3475 		goto done;
3476 
3477 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
3478 	if (err)
3479 		goto done;
3480 
3481 	err = ref_base_commit(worktree, repo);
3482 	if (err)
3483 		goto done;
3484 done:
3485 	if (head_tree)
3486 		got_object_tree_close(head_tree);
3487 	if (head_commit)
3488 		got_object_commit_close(head_commit);
3489 	free(head_commit_id2);
3490 	if (head_ref2) {
3491 		unlockerr = got_ref_unlock(head_ref2);
3492 		if (unlockerr && err == NULL)
3493 			err = unlockerr;
3494 		got_ref_close(head_ref2);
3495 	}
3496 	return err;
3497 }
3498 
3499 static const struct got_error *
3500 check_path_is_commitable(const char *path,
3501     struct got_pathlist_head *commitable_paths)
3502 {
3503 	struct got_pathlist_entry *cpe = NULL;
3504 	size_t path_len = strlen(path);
3505 
3506 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
3507 		struct got_commitable *ct = cpe->data;
3508 		const char *ct_path = ct->path;
3509 
3510 		while (ct_path[0] == '/')
3511 			ct_path++;
3512 
3513 		if (strcmp(path, ct_path) == 0 ||
3514 		    got_path_is_child(ct_path, path, path_len))
3515 			break;
3516 	}
3517 
3518 	if (cpe == NULL)
3519 		return got_error_path(path, GOT_ERR_BAD_PATH);
3520 
3521 	return NULL;
3522 }
3523 
3524 const struct got_error *
3525 got_worktree_commit(struct got_object_id **new_commit_id,
3526     struct got_worktree *worktree, struct got_pathlist_head *paths,
3527     const char *author, const char *committer,
3528     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
3529     got_worktree_status_cb status_cb, void *status_arg,
3530     struct got_repository *repo)
3531 {
3532 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
3533 	struct got_fileindex *fileindex = NULL;
3534 	char *fileindex_path = NULL;
3535 	struct got_pathlist_head commitable_paths;
3536 	struct collect_commitables_arg cc_arg;
3537 	struct got_pathlist_entry *pe;
3538 	struct got_reference *head_ref = NULL;
3539 	struct got_object_id *head_commit_id = NULL;
3540 
3541 	*new_commit_id = NULL;
3542 
3543 	TAILQ_INIT(&commitable_paths);
3544 
3545 	err = lock_worktree(worktree, LOCK_EX);
3546 	if (err)
3547 		goto done;
3548 
3549 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
3550 	if (err)
3551 		goto done;
3552 
3553 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
3554 	if (err)
3555 		goto done;
3556 
3557 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3558 	if (err)
3559 		goto done;
3560 
3561 	cc_arg.commitable_paths = &commitable_paths;
3562 	cc_arg.worktree = worktree;
3563 	cc_arg.repo = repo;
3564 	TAILQ_FOREACH(pe, paths, entry) {
3565 		err = worktree_status(worktree, pe->path, fileindex, repo,
3566 		    collect_commitables, &cc_arg, NULL, NULL);
3567 		if (err)
3568 			goto done;
3569 	}
3570 
3571 	if (TAILQ_EMPTY(&commitable_paths)) {
3572 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
3573 		goto done;
3574 	}
3575 
3576 	TAILQ_FOREACH(pe, paths, entry) {
3577 		err = check_path_is_commitable(pe->path, &commitable_paths);
3578 		if (err)
3579 			goto done;
3580 	}
3581 
3582 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3583 		struct got_commitable *ct = pe->data;
3584 		err = check_ct_out_of_date(ct, repo, head_commit_id);
3585 		if (err)
3586 			goto done;
3587 	}
3588 
3589 	err = commit_worktree(new_commit_id, &commitable_paths,
3590 	    head_commit_id, worktree, author, committer,
3591 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
3592 	if (err)
3593 		goto done;
3594 
3595 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
3596 	    fileindex);
3597 	sync_err = sync_fileindex(fileindex, fileindex_path);
3598 	if (sync_err && err == NULL)
3599 		err = sync_err;
3600 done:
3601 	if (fileindex)
3602 		got_fileindex_free(fileindex);
3603 	free(fileindex_path);
3604 	unlockerr = lock_worktree(worktree, LOCK_SH);
3605 	if (unlockerr && err == NULL)
3606 		err = unlockerr;
3607 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
3608 		struct got_commitable *ct = pe->data;
3609 		free_commitable(ct);
3610 	}
3611 	got_pathlist_free(&commitable_paths);
3612 	return err;
3613 }
3614 
3615 const char *
3616 got_commitable_get_path(struct got_commitable *ct)
3617 {
3618 	return ct->path;
3619 }
3620 
3621 unsigned int
3622 got_commitable_get_status(struct got_commitable *ct)
3623 {
3624 	return ct->status;
3625 }
3626 
3627 struct check_rebase_ok_arg {
3628 	struct got_worktree *worktree;
3629 	struct got_repository *repo;
3630 };
3631 
3632 static const struct got_error *
3633 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
3634 {
3635 	const struct got_error *err = NULL;
3636 	struct check_rebase_ok_arg *a = arg;
3637 	unsigned char status;
3638 	struct stat sb;
3639 	char *ondisk_path;
3640 
3641 	/* Reject rebase of a work tree with mixed base commits. */
3642 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
3643 	    SHA1_DIGEST_LENGTH))
3644 		return got_error(GOT_ERR_MIXED_COMMITS);
3645 
3646 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3647 	    == -1)
3648 		return got_error_from_errno("asprintf");
3649 
3650 	/* Reject rebase of a work tree with modified or conflicted files. */
3651 	err = get_file_status(&status, &sb, ie, ondisk_path, a->repo);
3652 	free(ondisk_path);
3653 	if (err)
3654 		return err;
3655 
3656 	if (status != GOT_STATUS_NO_CHANGE)
3657 		return got_error(GOT_ERR_MODIFIED);
3658 
3659 	return NULL;
3660 }
3661 
3662 const struct got_error *
3663 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
3664     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
3665     struct got_worktree *worktree, struct got_reference *branch,
3666     struct got_repository *repo)
3667 {
3668 	const struct got_error *err = NULL;
3669 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
3670 	char *branch_ref_name = NULL;
3671 	char *fileindex_path = NULL;
3672 	struct check_rebase_ok_arg ok_arg;
3673 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
3674 
3675 	*new_base_branch_ref = NULL;
3676 	*tmp_branch = NULL;
3677 	*fileindex = NULL;
3678 
3679 	err = lock_worktree(worktree, LOCK_EX);
3680 	if (err)
3681 		return err;
3682 
3683 	err = open_fileindex(fileindex, &fileindex_path, worktree);
3684 	if (err)
3685 		goto done;
3686 
3687 	ok_arg.worktree = worktree;
3688 	ok_arg.repo = repo;
3689 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
3690 	    &ok_arg);
3691 	if (err)
3692 		goto done;
3693 
3694 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3695 	if (err)
3696 		goto done;
3697 
3698 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3699 	if (err)
3700 		goto done;
3701 
3702 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3703 	if (err)
3704 		goto done;
3705 
3706 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
3707 	    0);
3708 	if (err)
3709 		goto done;
3710 
3711 	err = got_ref_alloc_symref(new_base_branch_ref,
3712 	    new_base_branch_ref_name, wt_branch);
3713 	if (err)
3714 		goto done;
3715 	err = got_ref_write(*new_base_branch_ref, repo);
3716 	if (err)
3717 		goto done;
3718 
3719 	/* TODO Lock original branch's ref while rebasing? */
3720 
3721 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
3722 	if (err)
3723 		goto done;
3724 
3725 	err = got_ref_write(branch_ref, repo);
3726 	if (err)
3727 		goto done;
3728 
3729 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
3730 	    worktree->base_commit_id);
3731 	if (err)
3732 		goto done;
3733 	err = got_ref_write(*tmp_branch, repo);
3734 	if (err)
3735 		goto done;
3736 
3737 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
3738 	if (err)
3739 		goto done;
3740 done:
3741 	free(fileindex_path);
3742 	free(tmp_branch_name);
3743 	free(new_base_branch_ref_name);
3744 	free(branch_ref_name);
3745 	if (branch_ref)
3746 		got_ref_close(branch_ref);
3747 	if (wt_branch)
3748 		got_ref_close(wt_branch);
3749 	if (err) {
3750 		if (*new_base_branch_ref) {
3751 			got_ref_close(*new_base_branch_ref);
3752 			*new_base_branch_ref = NULL;
3753 		}
3754 		if (*tmp_branch) {
3755 			got_ref_close(*tmp_branch);
3756 			*tmp_branch = NULL;
3757 		}
3758 		if (*fileindex) {
3759 			got_fileindex_free(*fileindex);
3760 			*fileindex = NULL;
3761 		}
3762 		lock_worktree(worktree, LOCK_SH);
3763 	}
3764 	return err;
3765 }
3766 
3767 const struct got_error *
3768 got_worktree_rebase_continue(struct got_object_id **commit_id,
3769     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
3770     struct got_reference **branch, struct got_fileindex **fileindex,
3771     struct got_worktree *worktree, struct got_repository *repo)
3772 {
3773 	const struct got_error *err;
3774 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
3775 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
3776 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
3777 	char *fileindex_path = NULL;
3778 
3779 	*commit_id = NULL;
3780 	*new_base_branch = NULL;
3781 	*tmp_branch = NULL;
3782 	*branch = NULL;
3783 	*fileindex = NULL;
3784 
3785 	err = lock_worktree(worktree, LOCK_EX);
3786 	if (err)
3787 		return err;
3788 
3789 	err = open_fileindex(fileindex, &fileindex_path, worktree);
3790 	if (err)
3791 		goto done;
3792 
3793 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3794 	if (err)
3795 		return err;
3796 
3797 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
3798 	if (err)
3799 		goto done;
3800 
3801 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
3802 	if (err)
3803 		goto done;
3804 
3805 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
3806 	if (err)
3807 		goto done;
3808 
3809 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
3810 	if (err)
3811 		goto done;
3812 
3813 	err = got_ref_open(branch, repo,
3814 	    got_ref_get_symref_target(branch_ref), 0);
3815 	if (err)
3816 		goto done;
3817 
3818 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3819 	if (err)
3820 		goto done;
3821 
3822 	err = got_ref_resolve(commit_id, repo, commit_ref);
3823 	if (err)
3824 		goto done;
3825 
3826 	err = got_ref_open(new_base_branch, repo,
3827 	    new_base_branch_ref_name, 0);
3828 	if (err)
3829 		goto done;
3830 
3831 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
3832 	if (err)
3833 		goto done;
3834 done:
3835 	free(commit_ref_name);
3836 	free(branch_ref_name);
3837 	free(fileindex_path);
3838 	if (commit_ref)
3839 		got_ref_close(commit_ref);
3840 	if (branch_ref)
3841 		got_ref_close(branch_ref);
3842 	if (err) {
3843 		free(*commit_id);
3844 		*commit_id = NULL;
3845 		if (*tmp_branch) {
3846 			got_ref_close(*tmp_branch);
3847 			*tmp_branch = NULL;
3848 		}
3849 		if (*new_base_branch) {
3850 			got_ref_close(*new_base_branch);
3851 			*new_base_branch = NULL;
3852 		}
3853 		if (*branch) {
3854 			got_ref_close(*branch);
3855 			*branch = NULL;
3856 		}
3857 		if (*fileindex) {
3858 			got_fileindex_free(*fileindex);
3859 			*fileindex = NULL;
3860 		}
3861 		lock_worktree(worktree, LOCK_SH);
3862 	}
3863 	return err;
3864 }
3865 
3866 const struct got_error *
3867 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
3868 {
3869 	const struct got_error *err;
3870 	char *tmp_branch_name = NULL;
3871 
3872 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
3873 	if (err)
3874 		return err;
3875 
3876 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
3877 	free(tmp_branch_name);
3878 	return NULL;
3879 }
3880 
3881 static const struct got_error *
3882 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
3883     char **logmsg, void *arg)
3884 {
3885 	*logmsg = arg;
3886 	return NULL;
3887 }
3888 
3889 static const struct got_error *
3890 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
3891     const char *path, struct got_object_id *blob_id,
3892     struct got_object_id *commit_id)
3893 {
3894 	return NULL;
3895 }
3896 
3897 struct collect_merged_paths_arg {
3898 	got_worktree_checkout_cb progress_cb;
3899 	void *progress_arg;
3900 	struct got_pathlist_head *merged_paths;
3901 };
3902 
3903 static const struct got_error *
3904 collect_merged_paths(void *arg, unsigned char status, const char *path)
3905 {
3906 	const struct got_error *err;
3907 	struct collect_merged_paths_arg *a = arg;
3908 	char *p;
3909 	struct got_pathlist_entry *new;
3910 
3911 	err = (*a->progress_cb)(a->progress_arg, status, path);
3912 	if (err)
3913 		return err;
3914 
3915 	if (status != GOT_STATUS_MERGE &&
3916 	    status != GOT_STATUS_ADD &&
3917 	    status != GOT_STATUS_DELETE &&
3918 	    status != GOT_STATUS_CONFLICT)
3919 		return NULL;
3920 
3921 	p = strdup(path);
3922 	if (p == NULL)
3923 		return got_error_from_errno("strdup");
3924 
3925 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
3926 	if (err || new == NULL)
3927 		free(p);
3928 	return err;
3929 }
3930 
3931 void
3932 got_worktree_rebase_pathlist_free(struct got_pathlist_head *merged_paths)
3933 {
3934 	struct got_pathlist_entry *pe;
3935 
3936 	TAILQ_FOREACH(pe, merged_paths, entry)
3937 		free((char *)pe->path);
3938 
3939 	got_pathlist_free(merged_paths);
3940 }
3941 
3942 static const struct got_error *
3943 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
3944     struct got_repository *repo)
3945 {
3946 	const struct got_error *err;
3947 	struct got_reference *commit_ref = NULL;
3948 
3949 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
3950 	if (err) {
3951 		if (err->code != GOT_ERR_NOT_REF)
3952 			goto done;
3953 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
3954 		if (err)
3955 			goto done;
3956 		err = got_ref_write(commit_ref, repo);
3957 		if (err)
3958 			goto done;
3959 	} else {
3960 		struct got_object_id *stored_id;
3961 		int cmp;
3962 
3963 		err = got_ref_resolve(&stored_id, repo, commit_ref);
3964 		if (err)
3965 			goto done;
3966 		cmp = got_object_id_cmp(commit_id, stored_id);
3967 		free(stored_id);
3968 		if (cmp != 0) {
3969 			err = got_error(GOT_ERR_REBASE_COMMITID);
3970 			goto done;
3971 		}
3972 	}
3973 done:
3974 	if (commit_ref)
3975 		got_ref_close(commit_ref);
3976 	return err;
3977 }
3978 
3979 static const struct got_error *
3980 rebase_merge_files(struct got_pathlist_head *merged_paths,
3981     const char *commit_ref_name, struct got_worktree *worktree,
3982     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
3983     struct got_object_id *commit_id, struct got_repository *repo,
3984     got_worktree_checkout_cb progress_cb, void *progress_arg,
3985     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
3986 {
3987 	const struct got_error *err;
3988 	struct got_reference *commit_ref = NULL;
3989 	struct collect_merged_paths_arg cmp_arg;
3990 	char *fileindex_path;
3991 
3992 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
3993 
3994 	err = get_fileindex_path(&fileindex_path, worktree);
3995 	if (err)
3996 		return err;
3997 
3998 	cmp_arg.progress_cb = progress_cb;
3999 	cmp_arg.progress_arg = progress_arg;
4000 	cmp_arg.merged_paths = merged_paths;
4001 	err = merge_files(worktree, fileindex, fileindex_path,
4002 	    parent_commit_id, commit_id, repo, collect_merged_paths,
4003 	    &cmp_arg, cancel_cb, cancel_arg);
4004 	if (commit_ref)
4005 		got_ref_close(commit_ref);
4006 	return err;
4007 }
4008 
4009 const struct got_error *
4010 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
4011     struct got_worktree *worktree, struct got_fileindex *fileindex,
4012     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4013     struct got_repository *repo,
4014     got_worktree_checkout_cb progress_cb, void *progress_arg,
4015     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
4016 {
4017 	const struct got_error *err;
4018 	char *commit_ref_name;
4019 
4020 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4021 	if (err)
4022 		return err;
4023 
4024 	err = store_commit_id(commit_ref_name, commit_id, repo);
4025 	if (err)
4026 		goto done;
4027 
4028 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4029 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4030 	    progress_arg, cancel_cb, cancel_arg);
4031 done:
4032 	free(commit_ref_name);
4033 	return err;
4034 }
4035 
4036 const struct got_error *
4037 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
4038     struct got_worktree *worktree, struct got_fileindex *fileindex,
4039     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
4040     struct got_repository *repo,
4041     got_worktree_checkout_cb progress_cb, void *progress_arg,
4042     got_worktree_cancel_cb cancel_cb, void *cancel_arg)
4043 {
4044 	const struct got_error *err;
4045 	char *commit_ref_name;
4046 
4047 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4048 	if (err)
4049 		return err;
4050 
4051 	err = store_commit_id(commit_ref_name, commit_id, repo);
4052 	if (err)
4053 		goto done;
4054 
4055 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
4056 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
4057 	    progress_arg, cancel_cb, cancel_arg);
4058 done:
4059 	free(commit_ref_name);
4060 	return err;
4061 }
4062 
4063 static const struct got_error *
4064 rebase_commit(struct got_object_id **new_commit_id,
4065     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
4066     struct got_worktree *worktree, struct got_fileindex *fileindex,
4067     struct got_reference *tmp_branch, struct got_commit_object *orig_commit,
4068     const char *new_logmsg, struct got_repository *repo)
4069 {
4070 	const struct got_error *err, *sync_err;
4071 	struct got_pathlist_head commitable_paths;
4072 	struct collect_commitables_arg cc_arg;
4073 	char *fileindex_path = NULL;
4074 	struct got_reference *head_ref = NULL;
4075 	struct got_object_id *head_commit_id = NULL;
4076 	char *logmsg = NULL;
4077 
4078 	TAILQ_INIT(&commitable_paths);
4079 	*new_commit_id = NULL;
4080 
4081 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
4082 
4083 	err = get_fileindex_path(&fileindex_path, worktree);
4084 	if (err)
4085 		return err;
4086 
4087 	cc_arg.commitable_paths = &commitable_paths;
4088 	cc_arg.worktree = worktree;
4089 	cc_arg.repo = repo;
4090 	/*
4091 	 * If possible get the status of individual files directly to
4092 	 * avoid crawling the entire work tree once per rebased commit.
4093 	 * TODO: Ideally, merged_paths would contain a list of commitables
4094 	 * we could use so we could skip worktree_status() entirely.
4095 	 */
4096 	if (merged_paths) {
4097 		struct got_pathlist_entry *pe;
4098 		if (TAILQ_EMPTY(merged_paths)) {
4099 			err = got_error(GOT_ERR_NO_MERGED_PATHS);
4100 			goto done;
4101 		}
4102 		TAILQ_FOREACH(pe, merged_paths, entry) {
4103 			err = worktree_status(worktree, pe->path, fileindex,
4104 			    repo, collect_commitables, &cc_arg, NULL, NULL);
4105 			if (err)
4106 				goto done;
4107 		}
4108 	} else {
4109 		err = worktree_status(worktree, "", fileindex, repo,
4110 		    collect_commitables, &cc_arg, NULL, NULL);
4111 		if (err)
4112 			goto done;
4113 	}
4114 
4115 	if (TAILQ_EMPTY(&commitable_paths)) {
4116 		/* No-op change; commit will be elided. */
4117 		err = got_ref_delete(commit_ref, repo);
4118 		if (err)
4119 			goto done;
4120 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
4121 		goto done;
4122 	}
4123 
4124 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
4125 	if (err)
4126 		goto done;
4127 
4128 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
4129 	if (err)
4130 		goto done;
4131 
4132 	if (new_logmsg)
4133 		logmsg = strdup(new_logmsg);
4134 	else
4135 		logmsg = strdup(got_object_commit_get_logmsg(orig_commit));
4136 	if (logmsg == NULL)
4137 		return got_error_from_errno("strdup");
4138 
4139 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
4140 	    worktree, got_object_commit_get_author(orig_commit),
4141 	    got_object_commit_get_committer(orig_commit),
4142 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
4143 	if (err)
4144 		goto done;
4145 
4146 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
4147 	if (err)
4148 		goto done;
4149 
4150 	err = got_ref_delete(commit_ref, repo);
4151 	if (err)
4152 		goto done;
4153 
4154 	err = update_fileindex_after_commit(&commitable_paths, *new_commit_id,
4155 	    fileindex);
4156 	sync_err = sync_fileindex(fileindex, fileindex_path);
4157 	if (sync_err && err == NULL)
4158 		err = sync_err;
4159 done:
4160 	free(fileindex_path);
4161 	free(head_commit_id);
4162 	if (head_ref)
4163 		got_ref_close(head_ref);
4164 	if (err) {
4165 		free(*new_commit_id);
4166 		*new_commit_id = NULL;
4167 	}
4168 	return err;
4169 }
4170 
4171 const struct got_error *
4172 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
4173     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4174     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4175     struct got_commit_object *orig_commit,
4176     struct got_object_id *orig_commit_id, struct got_repository *repo)
4177 {
4178 	const struct got_error *err;
4179 	char *commit_ref_name;
4180 	struct got_reference *commit_ref = NULL;
4181 	struct got_object_id *commit_id = NULL;
4182 
4183 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4184 	if (err)
4185 		return err;
4186 
4187 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4188 	if (err)
4189 		goto done;
4190 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4191 	if (err)
4192 		goto done;
4193 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4194 		err = got_error(GOT_ERR_REBASE_COMMITID);
4195 		goto done;
4196 	}
4197 
4198 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4199 	    worktree, fileindex, tmp_branch, orig_commit, NULL, repo);
4200 done:
4201 	if (commit_ref)
4202 		got_ref_close(commit_ref);
4203 	free(commit_ref_name);
4204 	free(commit_id);
4205 	return err;
4206 }
4207 
4208 const struct got_error *
4209 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
4210     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
4211     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4212     struct got_commit_object *orig_commit,
4213     struct got_object_id *orig_commit_id, const char *new_logmsg,
4214     struct got_repository *repo)
4215 {
4216 	const struct got_error *err;
4217 	char *commit_ref_name;
4218 	struct got_reference *commit_ref = NULL;
4219 	struct got_object_id *commit_id = NULL;
4220 
4221 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4222 	if (err)
4223 		return err;
4224 
4225 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4226 	if (err)
4227 		goto done;
4228 	err = got_ref_resolve(&commit_id, repo, commit_ref);
4229 	if (err)
4230 		goto done;
4231 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
4232 		err = got_error(GOT_ERR_HISTEDIT_COMMITID);
4233 		goto done;
4234 	}
4235 
4236 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
4237 	    worktree, fileindex, tmp_branch, orig_commit, new_logmsg, repo);
4238 done:
4239 	if (commit_ref)
4240 		got_ref_close(commit_ref);
4241 	free(commit_ref_name);
4242 	free(commit_id);
4243 	return err;
4244 }
4245 
4246 const struct got_error *
4247 got_worktree_rebase_postpone(struct got_worktree *worktree,
4248     struct got_fileindex *fileindex)
4249 {
4250 	if (fileindex)
4251 		got_fileindex_free(fileindex);
4252 	return lock_worktree(worktree, LOCK_SH);
4253 }
4254 
4255 static const struct got_error *
4256 delete_ref(const char *name, struct got_repository *repo)
4257 {
4258 	const struct got_error *err;
4259 	struct got_reference *ref;
4260 
4261 	err = got_ref_open(&ref, repo, name, 0);
4262 	if (err) {
4263 		if (err->code == GOT_ERR_NOT_REF)
4264 			return NULL;
4265 		return err;
4266 	}
4267 
4268 	err = got_ref_delete(ref, repo);
4269 	got_ref_close(ref);
4270 	return err;
4271 }
4272 
4273 static const struct got_error *
4274 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
4275 {
4276 	const struct got_error *err;
4277 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
4278 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
4279 
4280 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
4281 	if (err)
4282 		goto done;
4283 	err = delete_ref(tmp_branch_name, repo);
4284 	if (err)
4285 		goto done;
4286 
4287 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
4288 	if (err)
4289 		goto done;
4290 	err = delete_ref(new_base_branch_ref_name, repo);
4291 	if (err)
4292 		goto done;
4293 
4294 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
4295 	if (err)
4296 		goto done;
4297 	err = delete_ref(branch_ref_name, repo);
4298 	if (err)
4299 		goto done;
4300 
4301 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
4302 	if (err)
4303 		goto done;
4304 	err = delete_ref(commit_ref_name, repo);
4305 	if (err)
4306 		goto done;
4307 
4308 done:
4309 	free(tmp_branch_name);
4310 	free(new_base_branch_ref_name);
4311 	free(branch_ref_name);
4312 	free(commit_ref_name);
4313 	return err;
4314 }
4315 
4316 const struct got_error *
4317 got_worktree_rebase_complete(struct got_worktree *worktree,
4318     struct got_fileindex *fileindex, struct got_reference *new_base_branch,
4319     struct got_reference *tmp_branch, struct got_reference *rebased_branch,
4320     struct got_repository *repo)
4321 {
4322 	const struct got_error *err, *unlockerr;
4323 	struct got_object_id *new_head_commit_id = NULL;
4324 
4325 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
4326 	if (err)
4327 		return err;
4328 
4329 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
4330 	if (err)
4331 		goto done;
4332 
4333 	err = got_ref_write(rebased_branch, repo);
4334 	if (err)
4335 		goto done;
4336 
4337 	err = got_worktree_set_head_ref(worktree, rebased_branch);
4338 	if (err)
4339 		goto done;
4340 
4341 	err = delete_rebase_refs(worktree, repo);
4342 done:
4343 	if (fileindex)
4344 		got_fileindex_free(fileindex);
4345 	free(new_head_commit_id);
4346 	unlockerr = lock_worktree(worktree, LOCK_SH);
4347 	if (unlockerr && err == NULL)
4348 		err = unlockerr;
4349 	return err;
4350 }
4351 
4352 struct collect_revertible_paths_arg {
4353 	struct got_pathlist_head *revertible_paths;
4354 	struct got_worktree *worktree;
4355 };
4356 
4357 static const struct got_error *
4358 collect_revertible_paths(void *arg, unsigned char status,
4359     unsigned char staged_status, const char *relpath,
4360     struct got_object_id *blob_id, struct got_object_id *commit_id)
4361 {
4362 	struct collect_revertible_paths_arg *a = arg;
4363 	const struct got_error *err = NULL;
4364 	struct got_pathlist_entry *new = NULL;
4365 	char *path = NULL;
4366 
4367 	if (status != GOT_STATUS_ADD &&
4368 	    status != GOT_STATUS_DELETE &&
4369 	    status != GOT_STATUS_MODIFY &&
4370 	    status != GOT_STATUS_CONFLICT &&
4371 	    status != GOT_STATUS_MISSING)
4372 		return NULL;
4373 
4374 	if (asprintf(&path, "%s/%s", a->worktree->root_path, relpath) == -1)
4375 		return got_error_from_errno("asprintf");
4376 
4377 	err = got_pathlist_insert(&new, a->revertible_paths, path, NULL);
4378 	if (err || new == NULL)
4379 		free(path);
4380 	return err;
4381 }
4382 
4383 const struct got_error *
4384 got_worktree_rebase_abort(struct got_worktree *worktree,
4385     struct got_fileindex *fileindex, struct got_repository *repo,
4386     struct got_reference *new_base_branch,
4387      got_worktree_checkout_cb progress_cb, void *progress_arg)
4388 {
4389 	const struct got_error *err, *unlockerr, *sync_err;
4390 	struct got_reference *resolved = NULL;
4391 	struct got_object_id *commit_id = NULL;
4392 	char *fileindex_path = NULL;
4393 	struct got_pathlist_head revertible_paths;
4394 	struct got_pathlist_entry *pe;
4395 	struct collect_revertible_paths_arg crp_arg;
4396 	struct got_object_id *tree_id = NULL;
4397 
4398 	TAILQ_INIT(&revertible_paths);
4399 
4400 	err = lock_worktree(worktree, LOCK_EX);
4401 	if (err)
4402 		return err;
4403 
4404 	err = got_ref_open(&resolved, repo,
4405 	    got_ref_get_symref_target(new_base_branch), 0);
4406 	if (err)
4407 		goto done;
4408 
4409 	err = got_worktree_set_head_ref(worktree, resolved);
4410 	if (err)
4411 		goto done;
4412 
4413 	/*
4414 	 * XXX commits to the base branch could have happened while
4415 	 * we were busy rebasing; should we store the original commit ID
4416 	 * when rebase begins and read it back here?
4417 	 */
4418 	err = got_ref_resolve(&commit_id, repo, resolved);
4419 	if (err)
4420 		goto done;
4421 
4422 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
4423 	if (err)
4424 		goto done;
4425 
4426 	err = got_object_id_by_path(&tree_id, repo,
4427 	    worktree->base_commit_id, worktree->path_prefix);
4428 	if (err)
4429 		goto done;
4430 
4431 	err = delete_rebase_refs(worktree, repo);
4432 	if (err)
4433 		goto done;
4434 
4435 	err = get_fileindex_path(&fileindex_path, worktree);
4436 	if (err)
4437 		goto done;
4438 
4439 	crp_arg.revertible_paths = &revertible_paths;
4440 	crp_arg.worktree = worktree;
4441 	err = worktree_status(worktree, "", fileindex, repo,
4442 	    collect_revertible_paths, &crp_arg, NULL, NULL);
4443 	if (err)
4444 		goto done;
4445 
4446 	TAILQ_FOREACH(pe, &revertible_paths, entry) {
4447 		err = revert_file(worktree, fileindex, pe->path,
4448 		    progress_cb, progress_arg, repo);
4449 		if (err)
4450 			goto sync;
4451 	}
4452 
4453 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
4454 	    repo, progress_cb, progress_arg, NULL, NULL);
4455 sync:
4456 	sync_err = sync_fileindex(fileindex, fileindex_path);
4457 	if (sync_err && err == NULL)
4458 		err = sync_err;
4459 done:
4460 	got_ref_close(resolved);
4461 	free(tree_id);
4462 	free(commit_id);
4463 	if (fileindex)
4464 		got_fileindex_free(fileindex);
4465 	free(fileindex_path);
4466 	TAILQ_FOREACH(pe, &revertible_paths, entry)
4467 		free((char *)pe->path);
4468 	got_pathlist_free(&revertible_paths);
4469 
4470 	unlockerr = lock_worktree(worktree, LOCK_SH);
4471 	if (unlockerr && err == NULL)
4472 		err = unlockerr;
4473 	return err;
4474 }
4475 
4476 const struct got_error *
4477 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
4478     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
4479     struct got_fileindex **fileindex, struct got_worktree *worktree,
4480     struct got_repository *repo)
4481 {
4482 	const struct got_error *err = NULL;
4483 	char *tmp_branch_name = NULL;
4484 	char *branch_ref_name = NULL;
4485 	char *base_commit_ref_name = NULL;
4486 	char *fileindex_path = NULL;
4487 	struct check_rebase_ok_arg ok_arg;
4488 	struct got_reference *wt_branch = NULL;
4489 	struct got_reference *base_commit_ref = NULL;
4490 
4491 	*tmp_branch = NULL;
4492 	*branch_ref = NULL;
4493 	*base_commit_id = NULL;
4494 	*fileindex = NULL;
4495 
4496 	err = lock_worktree(worktree, LOCK_EX);
4497 	if (err)
4498 		return err;
4499 
4500 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4501 	if (err)
4502 		goto done;
4503 
4504 	ok_arg.worktree = worktree;
4505 	ok_arg.repo = repo;
4506 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
4507 	    &ok_arg);
4508 	if (err)
4509 		goto done;
4510 
4511 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4512 	if (err)
4513 		goto done;
4514 
4515 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4516 	if (err)
4517 		goto done;
4518 
4519 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4520 	    worktree);
4521 	if (err)
4522 		goto done;
4523 
4524 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
4525 	    0);
4526 	if (err)
4527 		goto done;
4528 
4529 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
4530 	if (err)
4531 		goto done;
4532 
4533 	err = got_ref_write(*branch_ref, repo);
4534 	if (err)
4535 		goto done;
4536 
4537 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
4538 	    worktree->base_commit_id);
4539 	if (err)
4540 		goto done;
4541 	err = got_ref_write(base_commit_ref, repo);
4542 	if (err)
4543 		goto done;
4544 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
4545 	if (*base_commit_id == NULL) {
4546 		err = got_error_from_errno("got_object_id_dup");
4547 		goto done;
4548 	}
4549 
4550 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
4551 	    worktree->base_commit_id);
4552 	if (err)
4553 		goto done;
4554 	err = got_ref_write(*tmp_branch, repo);
4555 	if (err)
4556 		goto done;
4557 
4558 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
4559 	if (err)
4560 		goto done;
4561 done:
4562 	free(fileindex_path);
4563 	free(tmp_branch_name);
4564 	free(branch_ref_name);
4565 	free(base_commit_ref_name);
4566 	if (wt_branch)
4567 		got_ref_close(wt_branch);
4568 	if (err) {
4569 		if (*branch_ref) {
4570 			got_ref_close(*branch_ref);
4571 			*branch_ref = NULL;
4572 		}
4573 		if (*tmp_branch) {
4574 			got_ref_close(*tmp_branch);
4575 			*tmp_branch = NULL;
4576 		}
4577 		free(*base_commit_id);
4578 		if (*fileindex) {
4579 			got_fileindex_free(*fileindex);
4580 			*fileindex = NULL;
4581 		}
4582 		lock_worktree(worktree, LOCK_SH);
4583 	}
4584 	return err;
4585 }
4586 
4587 const struct got_error *
4588 got_worktree_histedit_postpone(struct got_worktree *worktree,
4589     struct got_fileindex *fileindex)
4590 {
4591 	if (fileindex)
4592 		got_fileindex_free(fileindex);
4593 	return lock_worktree(worktree, LOCK_SH);
4594 }
4595 
4596 const struct got_error *
4597 got_worktree_histedit_in_progress(int *in_progress,
4598     struct got_worktree *worktree)
4599 {
4600 	const struct got_error *err;
4601 	char *tmp_branch_name = NULL;
4602 
4603 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4604 	if (err)
4605 		return err;
4606 
4607 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
4608 	free(tmp_branch_name);
4609 	return NULL;
4610 }
4611 
4612 const struct got_error *
4613 got_worktree_histedit_continue(struct got_object_id **commit_id,
4614     struct got_reference **tmp_branch, struct got_reference **branch_ref,
4615     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
4616     struct got_worktree *worktree, struct got_repository *repo)
4617 {
4618 	const struct got_error *err;
4619 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
4620 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
4621 	struct got_reference *commit_ref = NULL;
4622 	struct got_reference *base_commit_ref = NULL;
4623 	char *fileindex_path = NULL;
4624 
4625 	*commit_id = NULL;
4626 	*tmp_branch = NULL;
4627 	*base_commit_id = NULL;
4628 	*fileindex = NULL;
4629 
4630 	err = lock_worktree(worktree, LOCK_EX);
4631 	if (err)
4632 		return err;
4633 
4634 	err = open_fileindex(fileindex, &fileindex_path, worktree);
4635 	if (err)
4636 		goto done;
4637 
4638 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4639 	if (err)
4640 		return err;
4641 
4642 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4643 	if (err)
4644 		goto done;
4645 
4646 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4647 	if (err)
4648 		goto done;
4649 
4650 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4651 	    worktree);
4652 	if (err)
4653 		goto done;
4654 
4655 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
4656 	if (err)
4657 		goto done;
4658 
4659 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
4660 	if (err)
4661 		goto done;
4662 	err = got_ref_resolve(commit_id, repo, commit_ref);
4663 	if (err)
4664 		goto done;
4665 
4666 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
4667 	if (err)
4668 		goto done;
4669 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
4670 	if (err)
4671 		goto done;
4672 
4673 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
4674 	if (err)
4675 		goto done;
4676 done:
4677 	free(commit_ref_name);
4678 	free(branch_ref_name);
4679 	free(fileindex_path);
4680 	if (commit_ref)
4681 		got_ref_close(commit_ref);
4682 	if (base_commit_ref)
4683 		got_ref_close(base_commit_ref);
4684 	if (err) {
4685 		free(*commit_id);
4686 		*commit_id = NULL;
4687 		free(*base_commit_id);
4688 		*base_commit_id = NULL;
4689 		if (*tmp_branch) {
4690 			got_ref_close(*tmp_branch);
4691 			*tmp_branch = NULL;
4692 		}
4693 		if (*fileindex) {
4694 			got_fileindex_free(*fileindex);
4695 			*fileindex = NULL;
4696 		}
4697 		lock_worktree(worktree, LOCK_EX);
4698 	}
4699 	return err;
4700 }
4701 
4702 static const struct got_error *
4703 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
4704 {
4705 	const struct got_error *err;
4706 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
4707 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
4708 
4709 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
4710 	if (err)
4711 		goto done;
4712 	err = delete_ref(tmp_branch_name, repo);
4713 	if (err)
4714 		goto done;
4715 
4716 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
4717 	    worktree);
4718 	if (err)
4719 		goto done;
4720 	err = delete_ref(base_commit_ref_name, repo);
4721 	if (err)
4722 		goto done;
4723 
4724 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
4725 	if (err)
4726 		goto done;
4727 	err = delete_ref(branch_ref_name, repo);
4728 	if (err)
4729 		goto done;
4730 
4731 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4732 	if (err)
4733 		goto done;
4734 	err = delete_ref(commit_ref_name, repo);
4735 	if (err)
4736 		goto done;
4737 done:
4738 	free(tmp_branch_name);
4739 	free(base_commit_ref_name);
4740 	free(branch_ref_name);
4741 	free(commit_ref_name);
4742 	return err;
4743 }
4744 
4745 const struct got_error *
4746 got_worktree_histedit_abort(struct got_worktree *worktree,
4747     struct got_fileindex *fileindex, struct got_repository *repo,
4748     struct got_reference *branch, struct got_object_id *base_commit_id,
4749     got_worktree_checkout_cb progress_cb, void *progress_arg)
4750 {
4751 	const struct got_error *err, *unlockerr, *sync_err;
4752 	struct got_reference *resolved = NULL;
4753 	char *fileindex_path = NULL;
4754 	struct got_pathlist_head revertible_paths;
4755 	struct got_pathlist_entry *pe;
4756 	struct collect_revertible_paths_arg crp_arg;
4757 	struct got_object_id *tree_id = NULL;
4758 
4759 	TAILQ_INIT(&revertible_paths);
4760 
4761 	err = lock_worktree(worktree, LOCK_EX);
4762 	if (err)
4763 		return err;
4764 
4765 	err = got_ref_open(&resolved, repo,
4766 	    got_ref_get_symref_target(branch), 0);
4767 	if (err)
4768 		goto done;
4769 
4770 	err = got_worktree_set_head_ref(worktree, resolved);
4771 	if (err)
4772 		goto done;
4773 
4774 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
4775 	if (err)
4776 		goto done;
4777 
4778 	err = got_object_id_by_path(&tree_id, repo, base_commit_id,
4779 	    worktree->path_prefix);
4780 	if (err)
4781 		goto done;
4782 
4783 	err = delete_histedit_refs(worktree, repo);
4784 	if (err)
4785 		goto done;
4786 
4787 	err = get_fileindex_path(&fileindex_path, worktree);
4788 	if (err)
4789 		goto done;
4790 
4791 	crp_arg.revertible_paths = &revertible_paths;
4792 	crp_arg.worktree = worktree;
4793 	err = worktree_status(worktree, "", fileindex, repo,
4794 	    collect_revertible_paths, &crp_arg, NULL, NULL);
4795 	if (err)
4796 		goto done;
4797 
4798 	TAILQ_FOREACH(pe, &revertible_paths, entry) {
4799 		err = revert_file(worktree, fileindex, pe->path,
4800 		    progress_cb, progress_arg, repo);
4801 		if (err)
4802 			goto sync;
4803 	}
4804 
4805 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
4806 	    repo, progress_cb, progress_arg, NULL, NULL);
4807 sync:
4808 	sync_err = sync_fileindex(fileindex, fileindex_path);
4809 	if (sync_err && err == NULL)
4810 		err = sync_err;
4811 done:
4812 	got_ref_close(resolved);
4813 	free(tree_id);
4814 	free(fileindex_path);
4815 	TAILQ_FOREACH(pe, &revertible_paths, entry)
4816 		free((char *)pe->path);
4817 	got_pathlist_free(&revertible_paths);
4818 
4819 	unlockerr = lock_worktree(worktree, LOCK_SH);
4820 	if (unlockerr && err == NULL)
4821 		err = unlockerr;
4822 	return err;
4823 }
4824 
4825 const struct got_error *
4826 got_worktree_histedit_complete(struct got_worktree *worktree,
4827     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
4828     struct got_reference *edited_branch, struct got_repository *repo)
4829 {
4830 	const struct got_error *err, *unlockerr;
4831 	struct got_object_id *new_head_commit_id = NULL;
4832 	struct got_reference *resolved = NULL;
4833 
4834 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
4835 	if (err)
4836 		return err;
4837 
4838 	err = got_ref_open(&resolved, repo,
4839 	    got_ref_get_symref_target(edited_branch), 0);
4840 	if (err)
4841 		goto done;
4842 
4843 	err = got_ref_change_ref(resolved, new_head_commit_id);
4844 	if (err)
4845 		goto done;
4846 
4847 	err = got_ref_write(resolved, repo);
4848 	if (err)
4849 		goto done;
4850 
4851 	err = got_worktree_set_head_ref(worktree, resolved);
4852 	if (err)
4853 		goto done;
4854 
4855 	err = delete_histedit_refs(worktree, repo);
4856 done:
4857 	if (fileindex)
4858 		got_fileindex_free(fileindex);
4859 	free(new_head_commit_id);
4860 	unlockerr = lock_worktree(worktree, LOCK_SH);
4861 	if (unlockerr && err == NULL)
4862 		err = unlockerr;
4863 	return err;
4864 }
4865 
4866 const struct got_error *
4867 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
4868     struct got_object_id *commit_id, struct got_repository *repo)
4869 {
4870 	const struct got_error *err;
4871 	char *commit_ref_name;
4872 
4873 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
4874 	if (err)
4875 		return err;
4876 
4877 	err = store_commit_id(commit_ref_name, commit_id, repo);
4878 	if (err)
4879 		goto done;
4880 
4881 	err = delete_ref(commit_ref_name, repo);
4882 done:
4883 	free(commit_ref_name);
4884 	return err;
4885 }
4886 
4887 static const struct got_error *
4888 stage_path(const char *relpath, const char *ondisk_path,
4889     const char *path_content, struct got_worktree *worktree,
4890     struct got_fileindex *fileindex, struct got_repository *repo,
4891     got_worktree_status_cb status_cb, void *status_arg)
4892 {
4893 	const struct got_error *err = NULL;
4894 	struct got_fileindex_entry *ie;
4895 	unsigned char status;
4896 	struct stat sb;
4897 	struct got_object_id *blob_id = NULL;
4898 	uint32_t stage;
4899 
4900 	ie = got_fileindex_entry_get(fileindex, relpath, strlen(relpath));
4901 	if (ie == NULL) {
4902 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4903 		goto done;
4904 	}
4905 
4906 	err = get_file_status(&status, &sb, ie, ondisk_path, repo);
4907 	if (err)
4908 		goto done;
4909 
4910 	switch (status) {
4911 	case GOT_STATUS_ADD:
4912 	case GOT_STATUS_MODIFY:
4913 		err = got_object_blob_create(&blob_id,
4914 		    path_content ? path_content : ondisk_path, repo);
4915 		if (err)
4916 			goto done;
4917 		memcpy(ie->staged_blob_sha1, blob_id->sha1,
4918 		    SHA1_DIGEST_LENGTH);
4919 		if (status == GOT_STATUS_ADD)
4920 			stage = GOT_FILEIDX_STAGE_ADD;
4921 		else
4922 			stage = GOT_FILEIDX_STAGE_MODIFY;
4923 		break;
4924 	case GOT_STATUS_DELETE:
4925 		stage = GOT_FILEIDX_STAGE_DELETE;
4926 		break;
4927 	default:
4928 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4929 		goto done;
4930 	}
4931 
4932 	got_fileindex_entry_stage_set(ie, stage);
4933 	err = (*status_cb)(status_arg, GOT_STATUS_NO_CHANGE,
4934 	    get_staged_status(ie), relpath, blob_id, NULL);
4935 done:
4936 	free(blob_id);
4937 	return err;
4938 }
4939 
4940 const struct got_error *
4941 got_worktree_stage(struct got_worktree *worktree,
4942     struct got_pathlist_head *paths,
4943     got_worktree_status_cb status_cb, void *status_arg,
4944     struct got_repository *repo)
4945 {
4946 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4947 	struct got_pathlist_entry *pe;
4948 	struct got_fileindex *fileindex = NULL;
4949 	char *fileindex_path = NULL;
4950 
4951 	err = lock_worktree(worktree, LOCK_EX);
4952 	if (err)
4953 		return err;
4954 
4955 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4956 	if (err)
4957 		goto done;
4958 
4959 	TAILQ_FOREACH(pe, paths, entry) {
4960 		char *relpath;
4961 		err = got_path_skip_common_ancestor(&relpath,
4962 		    got_worktree_get_root_path(worktree), pe->path);
4963 		if (err)
4964 			break;
4965 		err = stage_path(relpath, pe->path,
4966 		    (const char *)pe->data, worktree, fileindex, repo,
4967 		    status_cb, status_arg);
4968 		free(relpath);
4969 		if (err)
4970 			break;
4971 	}
4972 
4973 	sync_err = sync_fileindex(fileindex, fileindex_path);
4974 	if (sync_err && err == NULL)
4975 		err = sync_err;
4976 done:
4977 	free(fileindex_path);
4978 	if (fileindex)
4979 		got_fileindex_free(fileindex);
4980 	unlockerr = lock_worktree(worktree, LOCK_SH);
4981 	if (unlockerr && err == NULL)
4982 		err = unlockerr;
4983 	return err;
4984 }