1 /*
2  * Copyright (c) 2018, 2019, 2020 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/queue.h>
19 #include <sys/tree.h>
20 
21 #include <dirent.h>
22 #include <limits.h>
23 #include <stddef.h>
24 #include <string.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <time.h>
28 #include <fcntl.h>
29 #include <errno.h>
30 #include <unistd.h>
31 #include <sha1.h>
32 #include <zlib.h>
33 #include <fnmatch.h>
34 #include <libgen.h>
35 #include <uuid.h>
36 #include <util.h>
37 
38 #include "got_error.h"
39 #include "got_repository.h"
40 #include "got_reference.h"
41 #include "got_object.h"
42 #include "got_path.h"
43 #include "got_cancel.h"
44 #include "got_worktree.h"
45 #include "got_opentemp.h"
46 #include "got_diff.h"
47 
48 #include "got_lib_worktree.h"
49 #include "got_lib_sha1.h"
50 #include "got_lib_fileindex.h"
51 #include "got_lib_inflate.h"
52 #include "got_lib_delta.h"
53 #include "got_lib_object.h"
54 #include "got_lib_object_parse.h"
55 #include "got_lib_object_create.h"
56 #include "got_lib_object_idset.h"
57 #include "got_lib_diff.h"
58 #include "got_lib_gotconfig.h"
59 
60 #ifndef MIN
61 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
62 #endif
63 
64 #define GOT_MERGE_LABEL_MERGED	"merged change"
65 #define GOT_MERGE_LABEL_BASE	"3-way merge base"
66 
67 static const struct got_error *
68 create_meta_file(const char *path_got, const char *name, const char *content)
69 {
70 	const struct got_error *err = NULL;
71 	char *path;
72 
73 	if (asprintf(&path, "%s/%s", path_got, name) == -1)
74 		return got_error_from_errno("asprintf");
75 
76 	err = got_path_create_file(path, content);
77 	free(path);
78 	return err;
79 }
80 
81 static const struct got_error *
82 update_meta_file(const char *path_got, const char *name, const char *content)
83 {
84 	const struct got_error *err = NULL;
85 	FILE *tmpfile = NULL;
86 	char *tmppath = NULL;
87 	char *path = NULL;
88 
89 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
90 		err = got_error_from_errno("asprintf");
91 		path = NULL;
92 		goto done;
93 	}
94 
95 	err = got_opentemp_named(&tmppath, &tmpfile, path);
96 	if (err)
97 		goto done;
98 
99 	if (content) {
100 		int len = fprintf(tmpfile, "%s\n", content);
101 		if (len != strlen(content) + 1) {
102 			err = got_error_from_errno2("fprintf", tmppath);
103 			goto done;
104 		}
105 	}
106 
107 	if (rename(tmppath, path) != 0) {
108 		err = got_error_from_errno3("rename", tmppath, path);
109 		unlink(tmppath);
110 		goto done;
111 	}
112 
113 done:
114 	if (fclose(tmpfile) == EOF && err == NULL)
115 		err = got_error_from_errno2("fclose", tmppath);
116 	free(tmppath);
117 	return err;
118 }
119 
120 static const struct got_error *
121 read_meta_file(char **content, const char *path_got, const char *name)
122 {
123 	const struct got_error *err = NULL;
124 	char *path;
125 	int fd = -1;
126 	ssize_t n;
127 	struct stat sb;
128 
129 	*content = NULL;
130 
131 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
132 		err = got_error_from_errno("asprintf");
133 		path = NULL;
134 		goto done;
135 	}
136 
137 	fd = open(path, O_RDONLY | O_NOFOLLOW);
138 	if (fd == -1) {
139 		if (errno == ENOENT)
140 			err = got_error_path(path, GOT_ERR_WORKTREE_META);
141 		else
142 			err = got_error_from_errno2("open", path);
143 		goto done;
144 	}
145 	if (flock(fd, LOCK_SH | LOCK_NB) == -1) {
146 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
147 		    : got_error_from_errno2("flock", path));
148 		goto done;
149 	}
150 
151 	if (fstat(fd, &sb) != 0) {
152 		err = got_error_from_errno2("fstat", path);
153 		goto done;
154 	}
155 	*content = calloc(1, sb.st_size);
156 	if (*content == NULL) {
157 		err = got_error_from_errno("calloc");
158 		goto done;
159 	}
160 
161 	n = read(fd, *content, sb.st_size);
162 	if (n != sb.st_size) {
163 		err = (n == -1 ? got_error_from_errno2("read", path) :
164 		    got_error_path(path, GOT_ERR_WORKTREE_META));
165 		goto done;
166 	}
167 	if ((*content)[sb.st_size - 1] != '\n') {
168 		err = got_error_path(path, GOT_ERR_WORKTREE_META);
169 		goto done;
170 	}
171 	(*content)[sb.st_size - 1] = '\0';
172 
173 done:
174 	if (fd != -1 && close(fd) == -1 && err == NULL)
175 		err = got_error_from_errno2("close", path_got);
176 	free(path);
177 	if (err) {
178 		free(*content);
179 		*content = NULL;
180 	}
181 	return err;
182 }
183 
184 static const struct got_error *
185 write_head_ref(const char *path_got, struct got_reference *head_ref)
186 {
187 	const struct got_error *err = NULL;
188 	char *refstr = NULL;
189 
190 	if (got_ref_is_symbolic(head_ref)) {
191 		refstr = got_ref_to_str(head_ref);
192 		if (refstr == NULL)
193 			return got_error_from_errno("got_ref_to_str");
194 	} else {
195 		refstr = strdup(got_ref_get_name(head_ref));
196 		if (refstr == NULL)
197 			return got_error_from_errno("strdup");
198 	}
199 	err = update_meta_file(path_got, GOT_WORKTREE_HEAD_REF, refstr);
200 	free(refstr);
201 	return err;
202 }
203 
204 const struct got_error *
205 got_worktree_init(const char *path, struct got_reference *head_ref,
206     const char *prefix, struct got_repository *repo)
207 {
208 	const struct got_error *err = NULL;
209 	struct got_object_id *commit_id = NULL;
210 	uuid_t uuid;
211 	uint32_t uuid_status;
212 	int obj_type;
213 	char *path_got = NULL;
214 	char *formatstr = NULL;
215 	char *absprefix = NULL;
216 	char *basestr = NULL;
217 	char *uuidstr = NULL;
218 
219 	if (strcmp(path, got_repo_get_path(repo)) == 0) {
220 		err = got_error(GOT_ERR_WORKTREE_REPO);
221 		goto done;
222 	}
223 
224 	err = got_ref_resolve(&commit_id, repo, head_ref);
225 	if (err)
226 		return err;
227 	err = got_object_get_type(&obj_type, repo, commit_id);
228 	if (err)
229 		return err;
230 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
231 		return got_error(GOT_ERR_OBJ_TYPE);
232 
233 	if (!got_path_is_absolute(prefix)) {
234 		if (asprintf(&absprefix, "/%s", prefix) == -1)
235 			return got_error_from_errno("asprintf");
236 	}
237 
238 	/* Create top-level directory (may already exist). */
239 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
240 		err = got_error_from_errno2("mkdir", path);
241 		goto done;
242 	}
243 
244 	/* Create .got directory (may already exist). */
245 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
246 		err = got_error_from_errno("asprintf");
247 		goto done;
248 	}
249 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
250 		err = got_error_from_errno2("mkdir", path_got);
251 		goto done;
252 	}
253 
254 	/* Create an empty lock file. */
255 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
256 	if (err)
257 		goto done;
258 
259 	/* Create an empty file index. */
260 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
261 	if (err)
262 		goto done;
263 
264 	/* Write the HEAD reference. */
265 	err = write_head_ref(path_got, head_ref);
266 	if (err)
267 		goto done;
268 
269 	/* Record our base commit. */
270 	err = got_object_id_str(&basestr, commit_id);
271 	if (err)
272 		goto done;
273 	err = create_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, basestr);
274 	if (err)
275 		goto done;
276 
277 	/* Store path to repository. */
278 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY,
279 	    got_repo_get_path(repo));
280 	if (err)
281 		goto done;
282 
283 	/* Store in-repository path prefix. */
284 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
285 	    absprefix ? absprefix : prefix);
286 	if (err)
287 		goto done;
288 
289 	/* Generate UUID. */
290 	uuid_create(&uuid, &uuid_status);
291 	if (uuid_status != uuid_s_ok) {
292 		err = got_error_uuid(uuid_status, "uuid_create");
293 		goto done;
294 	}
295 	uuid_to_string(&uuid, &uuidstr, &uuid_status);
296 	if (uuid_status != uuid_s_ok) {
297 		err = got_error_uuid(uuid_status, "uuid_to_string");
298 		goto done;
299 	}
300 	err = create_meta_file(path_got, GOT_WORKTREE_UUID, uuidstr);
301 	if (err)
302 		goto done;
303 
304 	/* Stamp work tree with format file. */
305 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
306 		err = got_error_from_errno("asprintf");
307 		goto done;
308 	}
309 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
310 	if (err)
311 		goto done;
312 
313 done:
314 	free(commit_id);
315 	free(path_got);
316 	free(formatstr);
317 	free(absprefix);
318 	free(basestr);
319 	free(uuidstr);
320 	return err;
321 }
322 
323 static const struct got_error *
324 open_worktree(struct got_worktree **worktree, const char *path)
325 {
326 	const struct got_error *err = NULL;
327 	char *path_got;
328 	char *formatstr = NULL;
329 	char *uuidstr = NULL;
330 	char *path_lock = NULL;
331 	char *base_commit_id_str = NULL;
332 	int version, fd = -1;
333 	const char *errstr;
334 	struct got_repository *repo = NULL;
335 	uint32_t uuid_status;
336 
337 	*worktree = NULL;
338 
339 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
340 		err = got_error_from_errno("asprintf");
341 		path_got = NULL;
342 		goto done;
343 	}
344 
345 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
346 		err = got_error_from_errno("asprintf");
347 		path_lock = NULL;
348 		goto done;
349 	}
350 
351 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
352 	if (fd == -1) {
353 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
354 		    : got_error_from_errno2("open", path_lock));
355 		goto done;
356 	}
357 
358 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
359 	if (err)
360 		goto done;
361 
362 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
363 	if (errstr) {
364 		err = got_error_msg(GOT_ERR_WORKTREE_META,
365 		    "could not parse work tree format version number");
366 		goto done;
367 	}
368 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
369 		err = got_error(GOT_ERR_WORKTREE_VERS);
370 		goto done;
371 	}
372 
373 	*worktree = calloc(1, sizeof(**worktree));
374 	if (*worktree == NULL) {
375 		err = got_error_from_errno("calloc");
376 		goto done;
377 	}
378 	(*worktree)->lockfd = -1;
379 
380 	(*worktree)->root_path = realpath(path, NULL);
381 	if ((*worktree)->root_path == NULL) {
382 		err = got_error_from_errno2("realpath", path);
383 		goto done;
384 	}
385 	err = read_meta_file(&(*worktree)->repo_path, path_got,
386 	    GOT_WORKTREE_REPOSITORY);
387 	if (err)
388 		goto done;
389 
390 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
391 	    GOT_WORKTREE_PATH_PREFIX);
392 	if (err)
393 		goto done;
394 
395 	err = read_meta_file(&base_commit_id_str, path_got,
396 	    GOT_WORKTREE_BASE_COMMIT);
397 	if (err)
398 		goto done;
399 
400 	err = read_meta_file(&uuidstr, path_got, GOT_WORKTREE_UUID);
401 	if (err)
402 		goto done;
403 	uuid_from_string(uuidstr, &(*worktree)->uuid, &uuid_status);
404 	if (uuid_status != uuid_s_ok) {
405 		err = got_error_uuid(uuid_status, "uuid_from_string");
406 		goto done;
407 	}
408 
409 	err = got_repo_open(&repo, (*worktree)->repo_path, NULL);
410 	if (err)
411 		goto done;
412 
413 	err = got_object_resolve_id_str(&(*worktree)->base_commit_id, repo,
414 	    base_commit_id_str);
415 	if (err)
416 		goto done;
417 
418 	err = read_meta_file(&(*worktree)->head_ref_name, path_got,
419 	    GOT_WORKTREE_HEAD_REF);
420 	if (err)
421 		goto done;
422 
423 	if (asprintf(&(*worktree)->gotconfig_path, "%s/%s/%s",
424 	    (*worktree)->root_path,
425 	    GOT_WORKTREE_GOT_DIR, GOT_GOTCONFIG_FILENAME) == -1) {
426 		err = got_error_from_errno("asprintf");
427 		goto done;
428 	}
429 
430 	err = got_gotconfig_read(&(*worktree)->gotconfig,
431 	    (*worktree)->gotconfig_path);
432 
433 	(*worktree)->root_fd = open((*worktree)->root_path, O_DIRECTORY);
434 	if ((*worktree)->root_fd == -1) {
435 		err = got_error_from_errno2("open", (*worktree)->root_path);
436 		goto done;
437 	}
438 done:
439 	if (repo) {
440 		const struct got_error *close_err = got_repo_close(repo);
441 		if (err == NULL)
442 			err = close_err;
443 	}
444 	free(path_got);
445 	free(path_lock);
446 	free(base_commit_id_str);
447 	free(uuidstr);
448 	free(formatstr);
449 	if (err) {
450 		if (fd != -1)
451 			close(fd);
452 		if (*worktree != NULL)
453 			got_worktree_close(*worktree);
454 		*worktree = NULL;
455 	} else
456 		(*worktree)->lockfd = fd;
457 
458 	return err;
459 }
460 
461 const struct got_error *
462 got_worktree_open(struct got_worktree **worktree, const char *path)
463 {
464 	const struct got_error *err = NULL;
465 	char *worktree_path;
466 
467 	worktree_path = strdup(path);
468 	if (worktree_path == NULL)
469 		return got_error_from_errno("strdup");
470 
471 	for (;;) {
472 		char *parent_path;
473 
474 		err = open_worktree(worktree, worktree_path);
475 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT)) {
476 			free(worktree_path);
477 			return err;
478 		}
479 		if (*worktree) {
480 			free(worktree_path);
481 			return NULL;
482 		}
483 		if (worktree_path[0] == '/' && worktree_path[1] == '\0')
484 			break;
485 		err = got_path_dirname(&parent_path, worktree_path);
486 		if (err) {
487 			if (err->code != GOT_ERR_BAD_PATH) {
488 				free(worktree_path);
489 				return err;
490 			}
491 			break;
492 		}
493 		free(worktree_path);
494 		worktree_path = parent_path;
495 	}
496 
497 	free(worktree_path);
498 	return got_error(GOT_ERR_NOT_WORKTREE);
499 }
500 
501 const struct got_error *
502 got_worktree_close(struct got_worktree *worktree)
503 {
504 	const struct got_error *err = NULL;
505 
506 	if (worktree->lockfd != -1) {
507 		if (close(worktree->lockfd) == -1)
508 			err = got_error_from_errno2("close",
509 			    got_worktree_get_root_path(worktree));
510 	}
511 	if (close(worktree->root_fd) == -1 && err == NULL)
512 		err = got_error_from_errno2("close",
513 		    got_worktree_get_root_path(worktree));
514 	free(worktree->repo_path);
515 	free(worktree->path_prefix);
516 	free(worktree->base_commit_id);
517 	free(worktree->head_ref_name);
518 	free(worktree->root_path);
519 	free(worktree->gotconfig_path);
520 	got_gotconfig_free(worktree->gotconfig);
521 	free(worktree);
522 	return err;
523 }
524 
525 const char *
526 got_worktree_get_root_path(struct got_worktree *worktree)
527 {
528 	return worktree->root_path;
529 }
530 
531 const char *
532 got_worktree_get_repo_path(struct got_worktree *worktree)
533 {
534 	return worktree->repo_path;
535 }
536 const char *
537 got_worktree_get_path_prefix(struct got_worktree *worktree)
538 {
539 	return worktree->path_prefix;
540 }
541 
542 const struct got_error *
543 got_worktree_match_path_prefix(int *match, struct got_worktree *worktree,
544     const char *path_prefix)
545 {
546 	char *absprefix = NULL;
547 
548 	if (!got_path_is_absolute(path_prefix)) {
549 		if (asprintf(&absprefix, "/%s", path_prefix) == -1)
550 			return got_error_from_errno("asprintf");
551 	}
552 	*match = (strcmp(absprefix ? absprefix : path_prefix,
553 	    worktree->path_prefix) == 0);
554 	free(absprefix);
555 	return NULL;
556 }
557 
558 const char *
559 got_worktree_get_head_ref_name(struct got_worktree *worktree)
560 {
561 	return worktree->head_ref_name;
562 }
563 
564 const struct got_error *
565 got_worktree_set_head_ref(struct got_worktree *worktree,
566     struct got_reference *head_ref)
567 {
568 	const struct got_error *err = NULL;
569 	char *path_got = NULL, *head_ref_name = NULL;
570 
571 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
572 	    GOT_WORKTREE_GOT_DIR) == -1) {
573 		err = got_error_from_errno("asprintf");
574 		path_got = NULL;
575 		goto done;
576 	}
577 
578 	head_ref_name = strdup(got_ref_get_name(head_ref));
579 	if (head_ref_name == NULL) {
580 		err = got_error_from_errno("strdup");
581 		goto done;
582 	}
583 
584 	err = write_head_ref(path_got, head_ref);
585 	if (err)
586 		goto done;
587 
588 	free(worktree->head_ref_name);
589 	worktree->head_ref_name = head_ref_name;
590 done:
591 	free(path_got);
592 	if (err)
593 		free(head_ref_name);
594 	return err;
595 }
596 
597 struct got_object_id *
598 got_worktree_get_base_commit_id(struct got_worktree *worktree)
599 {
600 	return worktree->base_commit_id;
601 }
602 
603 const struct got_error *
604 got_worktree_set_base_commit_id(struct got_worktree *worktree,
605     struct got_repository *repo, struct got_object_id *commit_id)
606 {
607 	const struct got_error *err;
608 	struct got_object *obj = NULL;
609 	char *id_str = NULL;
610 	char *path_got = NULL;
611 
612 	if (asprintf(&path_got, "%s/%s", worktree->root_path,
613 	    GOT_WORKTREE_GOT_DIR) == -1) {
614 		err = got_error_from_errno("asprintf");
615 		path_got = NULL;
616 		goto done;
617 	}
618 
619 	err = got_object_open(&obj, repo, commit_id);
620 	if (err)
621 		return err;
622 
623 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
624 		err = got_error(GOT_ERR_OBJ_TYPE);
625 		goto done;
626 	}
627 
628 	/* Record our base commit. */
629 	err = got_object_id_str(&id_str, commit_id);
630 	if (err)
631 		goto done;
632 	err = update_meta_file(path_got, GOT_WORKTREE_BASE_COMMIT, id_str);
633 	if (err)
634 		goto done;
635 
636 	free(worktree->base_commit_id);
637 	worktree->base_commit_id = got_object_id_dup(commit_id);
638 	if (worktree->base_commit_id == NULL) {
639 		err = got_error_from_errno("got_object_id_dup");
640 		goto done;
641 	}
642 done:
643 	if (obj)
644 		got_object_close(obj);
645 	free(id_str);
646 	free(path_got);
647 	return err;
648 }
649 
650 const struct got_gotconfig *
651 got_worktree_get_gotconfig(struct got_worktree *worktree)
652 {
653 	return worktree->gotconfig;
654 }
655 
656 static const struct got_error *
657 lock_worktree(struct got_worktree *worktree, int operation)
658 {
659 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
660 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
661 		    : got_error_from_errno2("flock",
662 		    got_worktree_get_root_path(worktree)));
663 	return NULL;
664 }
665 
666 static const struct got_error *
667 add_dir_on_disk(struct got_worktree *worktree, const char *path)
668 {
669 	const struct got_error *err = NULL;
670 	char *abspath;
671 
672 	if (asprintf(&abspath, "%s/%s", worktree->root_path, path) == -1)
673 		return got_error_from_errno("asprintf");
674 
675 	err = got_path_mkdir(abspath);
676 	if (err && err->code == GOT_ERR_ERRNO && errno == EEXIST) {
677 		struct stat sb;
678 		err = NULL;
679 		if (lstat(abspath, &sb) == -1) {
680 			err = got_error_from_errno2("lstat", abspath);
681 		} else if (!S_ISDIR(sb.st_mode)) {
682 			/* TODO directory is obstructed; do something */
683 			err = got_error_path(abspath, GOT_ERR_FILE_OBSTRUCTED);
684 		}
685 	}
686 	free(abspath);
687 	return err;
688 }
689 
690 static const struct got_error *
691 check_file_contents_equal(int *same, FILE *f1, FILE *f2)
692 {
693 	const struct got_error *err = NULL;
694 	uint8_t fbuf1[8192];
695 	uint8_t fbuf2[8192];
696 	size_t flen1 = 0, flen2 = 0;
697 
698 	*same = 1;
699 
700 	for (;;) {
701 		flen1 = fread(fbuf1, 1, sizeof(fbuf1), f1);
702 		if (flen1 == 0 && ferror(f1)) {
703 			err = got_error_from_errno("fread");
704 			break;
705 		}
706 		flen2 = fread(fbuf2, 1, sizeof(fbuf2), f2);
707 		if (flen2 == 0 && ferror(f2)) {
708 			err = got_error_from_errno("fread");
709 			break;
710 		}
711 		if (flen1 == 0) {
712 			if (flen2 != 0)
713 				*same = 0;
714 			break;
715 		} else if (flen2 == 0) {
716 			if (flen1 != 0)
717 				*same = 0;
718 			break;
719 		} else if (flen1 == flen2) {
720 			if (memcmp(fbuf1, fbuf2, flen2) != 0) {
721 				*same = 0;
722 				break;
723 			}
724 		} else {
725 			*same = 0;
726 			break;
727 		}
728 	}
729 
730 	return err;
731 }
732 
733 static const struct got_error *
734 check_files_equal(int *same, FILE *f1, FILE *f2)
735 {
736 	struct stat sb;
737 	size_t size1, size2;
738 
739 	*same = 1;
740 
741 	if (fstat(fileno(f1), &sb) != 0)
742 		return got_error_from_errno("fstat");
743 	size1 = sb.st_size;
744 
745 	if (fstat(fileno(f2), &sb) != 0)
746 		return got_error_from_errno("fstat");
747 	size2 = sb.st_size;
748 
749 	if (size1 != size2) {
750 		*same = 0;
751 		return NULL;
752 	}
753 
754 	if (fseek(f1, 0L, SEEK_SET) == -1)
755 		return got_ferror(f1, GOT_ERR_IO);
756 	if (fseek(f2, 0L, SEEK_SET) == -1)
757 		return got_ferror(f2, GOT_ERR_IO);
758 
759 	return check_file_contents_equal(same, f1, f2);
760 }
761 
762 /*
763  * Perform a 3-way merge where the file f_orig acts as the common
764  * ancestor, the file f_deriv acts as the first derived version,
765  * and the file f_deriv2 acts as the second derived version.
766  * The merge result will be written to a new file at ondisk_path; any
767  * existing file at this path will be replaced.
768  */
769 static const struct got_error *
770 merge_file(int *local_changes_subsumed, struct got_worktree *worktree,
771     FILE *f_orig, FILE *f_deriv, FILE *f_deriv2, const char *ondisk_path,
772     const char *path, uint16_t st_mode,
773     const char *label_orig, const char *label_deriv, const char *label_deriv2,
774     enum got_diff_algorithm diff_algo, struct got_repository *repo,
775     got_worktree_checkout_cb progress_cb, void *progress_arg)
776 {
777 	const struct got_error *err = NULL;
778 	int merged_fd = -1;
779 	FILE *f_merged = NULL;
780 	char *merged_path = NULL, *base_path = NULL;
781 	int overlapcnt = 0;
782 	char *parent = NULL;
783 
784 	*local_changes_subsumed = 0;
785 
786 	err = got_path_dirname(&parent, ondisk_path);
787 	if (err)
788 		return err;
789 
790 	if (asprintf(&base_path, "%s/got-merged", parent) == -1) {
791 		err = got_error_from_errno("asprintf");
792 		goto done;
793 	}
794 
795 	err = got_opentemp_named_fd(&merged_path, &merged_fd, base_path);
796 	if (err)
797 		goto done;
798 
799 	err = got_merge_diff3(&overlapcnt, merged_fd, f_deriv, f_orig,
800 	    f_deriv2, label_deriv, label_orig, label_deriv2, diff_algo);
801 	if (err)
802 		goto done;
803 
804 	err = (*progress_cb)(progress_arg,
805 	    overlapcnt > 0 ? GOT_STATUS_CONFLICT : GOT_STATUS_MERGE, path);
806 	if (err)
807 		goto done;
808 
809 	if (fsync(merged_fd) != 0) {
810 		err = got_error_from_errno("fsync");
811 		goto done;
812 	}
813 
814 	f_merged = fdopen(merged_fd, "r");
815 	if (f_merged == NULL) {
816 		err = got_error_from_errno("fdopen");
817 		goto done;
818 	}
819 	merged_fd = -1;
820 
821 	/* Check if a clean merge has subsumed all local changes. */
822 	if (overlapcnt == 0) {
823 		err = check_files_equal(local_changes_subsumed, f_deriv,
824 		    f_merged);
825 		if (err)
826 			goto done;
827 	}
828 
829 	if (fchmod(fileno(f_merged), st_mode) != 0) {
830 		err = got_error_from_errno2("fchmod", merged_path);
831 		goto done;
832 	}
833 
834 	if (rename(merged_path, ondisk_path) != 0) {
835 		err = got_error_from_errno3("rename", merged_path,
836 		    ondisk_path);
837 		goto done;
838 	}
839 done:
840 	if (err) {
841 		if (merged_path)
842 			unlink(merged_path);
843 	}
844 	if (merged_fd != -1 && close(merged_fd) == -1 && err == NULL)
845 		err = got_error_from_errno("close");
846 	if (f_merged && fclose(f_merged) == EOF && err == NULL)
847 		err = got_error_from_errno("fclose");
848 	free(merged_path);
849 	free(base_path);
850 	free(parent);
851 	return err;
852 }
853 
854 static const struct got_error *
855 update_symlink(const char *ondisk_path, const char *target_path,
856     size_t target_len)
857 {
858 	/* This is not atomic but matches what 'ln -sf' does. */
859 	if (unlink(ondisk_path) == -1)
860 		return got_error_from_errno2("unlink", ondisk_path);
861 	if (symlink(target_path, ondisk_path) == -1)
862 		return got_error_from_errno3("symlink", target_path,
863 		    ondisk_path);
864 	return NULL;
865 }
866 
867 /*
868  * Overwrite a symlink (or a regular file in case there was a "bad" symlink)
869  * in the work tree with a file that contains conflict markers and the
870  * conflicting target paths of the original version, a "derived version"
871  * of a symlink from an incoming change, and a local version of the symlink.
872  *
873  * The original versions's target path can be NULL if it is not available,
874  * such as if both derived versions added a new symlink at the same path.
875  *
876  * The incoming derived symlink target is NULL in case the incoming change
877  * has deleted this symlink.
878  */
879 static const struct got_error *
880 install_symlink_conflict(const char *deriv_target,
881     struct got_object_id *deriv_base_commit_id, const char *orig_target,
882     const char *label_orig, const char *local_target, const char *ondisk_path)
883 {
884 	const struct got_error *err;
885 	char *id_str = NULL, *label_deriv = NULL, *path = NULL;
886 	FILE *f = NULL;
887 
888 	err = got_object_id_str(&id_str, deriv_base_commit_id);
889 	if (err)
890 		return got_error_from_errno("asprintf");
891 
892 	if (asprintf(&label_deriv, "%s: commit %s",
893 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
894 		err = got_error_from_errno("asprintf");
895 		goto done;
896 	}
897 
898 	err = got_opentemp_named(&path, &f, "got-symlink-conflict");
899 	if (err)
900 		goto done;
901 
902 	if (fchmod(fileno(f), GOT_DEFAULT_FILE_MODE) == -1) {
903 		err = got_error_from_errno2("fchmod", path);
904 		goto done;
905 	}
906 
907 	if (fprintf(f, "%s %s\n%s\n%s%s%s%s%s\n%s\n%s\n",
908 	    GOT_DIFF_CONFLICT_MARKER_BEGIN, label_deriv,
909 	    deriv_target ? deriv_target : "(symlink was deleted)",
910 	    orig_target ? label_orig : "",
911 	    orig_target ? "\n" : "",
912 	    orig_target ? orig_target : "",
913 	    orig_target ? "\n" : "",
914 	    GOT_DIFF_CONFLICT_MARKER_SEP,
915 	    local_target, GOT_DIFF_CONFLICT_MARKER_END) < 0) {
916 		err = got_error_from_errno2("fprintf", path);
917 		goto done;
918 	}
919 
920 	if (unlink(ondisk_path) == -1) {
921 		err = got_error_from_errno2("unlink", ondisk_path);
922 		goto done;
923 	}
924 	if (rename(path, ondisk_path) == -1) {
925 		err = got_error_from_errno3("rename", path, ondisk_path);
926 		goto done;
927 	}
928 done:
929 	if (f != NULL && fclose(f) == EOF && err == NULL)
930 		err = got_error_from_errno2("fclose", path);
931 	free(path);
932 	free(id_str);
933 	free(label_deriv);
934 	return err;
935 }
936 
937 /* forward declaration */
938 static const struct got_error *
939 merge_blob(int *, struct got_worktree *, struct got_blob_object *,
940     const char *, const char *, uint16_t, const char *,
941     struct got_blob_object *, struct got_object_id *,
942     struct got_repository *, got_worktree_checkout_cb, void *);
943 
944 /*
945  * Merge a symlink into the work tree, where blob_orig acts as the common
946  * ancestor, deriv_target is the link target of the first derived version,
947  * and the symlink on disk acts as the second derived version.
948  * Assume that contents of both blobs represent symlinks.
949  */
950 static const struct got_error *
951 merge_symlink(struct got_worktree *worktree,
952     struct got_blob_object *blob_orig, const char *ondisk_path,
953     const char *path, const char *label_orig, const char *deriv_target,
954     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
955     got_worktree_checkout_cb progress_cb, void *progress_arg)
956 {
957 	const struct got_error *err = NULL;
958 	char *ancestor_target = NULL;
959 	struct stat sb;
960 	ssize_t ondisk_len, deriv_len;
961 	char ondisk_target[PATH_MAX];
962 	int have_local_change = 0;
963 	int have_incoming_change = 0;
964 
965 	if (lstat(ondisk_path, &sb) == -1)
966 		return got_error_from_errno2("lstat", ondisk_path);
967 
968 	ondisk_len = readlink(ondisk_path, ondisk_target,
969 	    sizeof(ondisk_target));
970 	if (ondisk_len == -1) {
971 		err = got_error_from_errno2("readlink",
972 		    ondisk_path);
973 		goto done;
974 	}
975 	ondisk_target[ondisk_len] = '\0';
976 
977 	if (blob_orig) {
978 		err = got_object_blob_read_to_str(&ancestor_target, blob_orig);
979 		if (err)
980 			goto done;
981 	}
982 
983 	if (ancestor_target == NULL ||
984 	    (ondisk_len != strlen(ancestor_target) ||
985 	    memcmp(ondisk_target, ancestor_target, ondisk_len) != 0))
986 		have_local_change = 1;
987 
988 	deriv_len = strlen(deriv_target);
989 	if (ancestor_target == NULL ||
990 	    (deriv_len != strlen(ancestor_target) ||
991 	    memcmp(deriv_target, ancestor_target, deriv_len) != 0))
992 		have_incoming_change = 1;
993 
994 	if (!have_local_change && !have_incoming_change) {
995 		if (ancestor_target) {
996 			/* Both sides made the same change. */
997 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
998 			    path);
999 		} else if (deriv_len == ondisk_len &&
1000 		    memcmp(ondisk_target, deriv_target, deriv_len) == 0) {
1001 			/* Both sides added the same symlink. */
1002 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
1003 			    path);
1004 		} else {
1005 			/* Both sides added symlinks which don't match. */
1006 			err = install_symlink_conflict(deriv_target,
1007 			    deriv_base_commit_id, ancestor_target,
1008 			    label_orig, ondisk_target, ondisk_path);
1009 			if (err)
1010 				goto done;
1011 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
1012 			    path);
1013 		}
1014 	} else if (!have_local_change && have_incoming_change) {
1015 		/* Apply the incoming change. */
1016 		err = update_symlink(ondisk_path, deriv_target,
1017 		    strlen(deriv_target));
1018 		if (err)
1019 			goto done;
1020 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
1021 	} else if (have_local_change && have_incoming_change) {
1022 		if (deriv_len == ondisk_len &&
1023 		    memcmp(deriv_target, ondisk_target, deriv_len) == 0) {
1024 			/* Both sides made the same change. */
1025 			err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE,
1026 			    path);
1027 		} else {
1028 			err = install_symlink_conflict(deriv_target,
1029 			    deriv_base_commit_id, ancestor_target, label_orig,
1030 			    ondisk_target, ondisk_path);
1031 			if (err)
1032 				goto done;
1033 			err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
1034 			    path);
1035 		}
1036 	}
1037 
1038 done:
1039 	free(ancestor_target);
1040 	return err;
1041 }
1042 
1043 static const struct got_error *
1044 dump_symlink_target_path_to_file(FILE **outfile, const char *ondisk_path)
1045 {
1046 	const struct got_error *err = NULL;
1047 	char target_path[PATH_MAX];
1048 	ssize_t target_len;
1049 	size_t n;
1050 	FILE *f;
1051 
1052 	*outfile = NULL;
1053 
1054 	f = got_opentemp();
1055 	if (f == NULL)
1056 		return got_error_from_errno("got_opentemp");
1057 	target_len = readlink(ondisk_path, target_path, sizeof(target_path));
1058 	if (target_len == -1) {
1059 		err = got_error_from_errno2("readlink", ondisk_path);
1060 		goto done;
1061 	}
1062 	n = fwrite(target_path, 1, target_len, f);
1063 	if (n != target_len) {
1064 		err = got_ferror(f, GOT_ERR_IO);
1065 		goto done;
1066 	}
1067 	if (fflush(f) == EOF) {
1068 		err = got_error_from_errno("fflush");
1069 		goto done;
1070 	}
1071 	if (fseek(f, 0L, SEEK_SET) == -1) {
1072 		err = got_ferror(f, GOT_ERR_IO);
1073 		goto done;
1074 	}
1075 done:
1076 	if (err)
1077 		fclose(f);
1078 	else
1079 		*outfile = f;
1080 	return err;
1081 }
1082 
1083 /*
1084  * Perform a 3-way merge where blob_orig acts as the common ancestor,
1085  * blob_deriv acts as the first derived version, and the file on disk
1086  * acts as the second derived version.
1087  */
1088 static const struct got_error *
1089 merge_blob(int *local_changes_subsumed, struct got_worktree *worktree,
1090     struct got_blob_object *blob_orig, const char *ondisk_path,
1091     const char *path, uint16_t st_mode, const char *label_orig,
1092     struct got_blob_object *blob_deriv,
1093     struct got_object_id *deriv_base_commit_id, struct got_repository *repo,
1094     got_worktree_checkout_cb progress_cb, void *progress_arg)
1095 {
1096 	const struct got_error *err = NULL;
1097 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
1098 	char *blob_orig_path = NULL;
1099 	char *blob_deriv_path = NULL, *base_path = NULL, *id_str = NULL;
1100 	char *label_deriv = NULL, *parent = NULL;
1101 
1102 	*local_changes_subsumed = 0;
1103 
1104 	err = got_path_dirname(&parent, ondisk_path);
1105 	if (err)
1106 		return err;
1107 
1108 	if (blob_orig) {
1109 		if (asprintf(&base_path, "%s/got-merge-blob-orig",
1110 		    parent) == -1) {
1111 			err = got_error_from_errno("asprintf");
1112 			base_path = NULL;
1113 			goto done;
1114 		}
1115 
1116 		err = got_opentemp_named(&blob_orig_path, &f_orig, base_path);
1117 		if (err)
1118 			goto done;
1119 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_orig,
1120 		    blob_orig);
1121 		if (err)
1122 			goto done;
1123 		free(base_path);
1124 	} else {
1125 		/*
1126 		 * No common ancestor exists. This is an "add vs add" conflict
1127 		 * and we simply use an empty ancestor file to make both files
1128 		 * appear in the merged result in their entirety.
1129 		 */
1130 		f_orig = got_opentemp();
1131 		if (f_orig == NULL) {
1132 			err = got_error_from_errno("got_opentemp");
1133 			goto done;
1134 		}
1135 	}
1136 
1137 	if (asprintf(&base_path, "%s/got-merge-blob-deriv", parent) == -1) {
1138 		err = got_error_from_errno("asprintf");
1139 		base_path = NULL;
1140 		goto done;
1141 	}
1142 
1143 	err = got_opentemp_named(&blob_deriv_path, &f_deriv, base_path);
1144 	if (err)
1145 		goto done;
1146 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_deriv,
1147 	    blob_deriv);
1148 	if (err)
1149 		goto done;
1150 
1151 	err = got_object_id_str(&id_str, deriv_base_commit_id);
1152 	if (err)
1153 		goto done;
1154 	if (asprintf(&label_deriv, "%s: commit %s",
1155 	    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
1156 		err = got_error_from_errno("asprintf");
1157 		goto done;
1158 	}
1159 
1160 	/* 
1161 	 * In order the run a 3-way merge with a symlink we copy the symlink's
1162 	 * target path into a temporary file and use that file with diff3.
1163 	 */
1164 	if (S_ISLNK(st_mode)) {
1165 		err = dump_symlink_target_path_to_file(&f_deriv2, ondisk_path);
1166 		if (err)
1167 			goto done;
1168 	} else {
1169 		int fd;
1170 		fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW);
1171 		if (fd == -1) {
1172 			err = got_error_from_errno2("open", ondisk_path);
1173 			goto done;
1174 		}
1175 		f_deriv2 = fdopen(fd, "r");
1176 		if (f_deriv2 == NULL) {
1177 			err = got_error_from_errno2("fdopen", ondisk_path);
1178 			close(fd);
1179 			goto done;
1180 		}
1181 	}
1182 
1183 	err = merge_file(local_changes_subsumed, worktree, f_orig, f_deriv,
1184 	    f_deriv2, ondisk_path, path, st_mode, label_orig, label_deriv,
1185 	    NULL, GOT_DIFF_ALGORITHM_MYERS, repo, progress_cb, progress_arg);
1186 done:
1187 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
1188 		err = got_error_from_errno("fclose");
1189 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
1190 		err = got_error_from_errno("fclose");
1191 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
1192 		err = got_error_from_errno("fclose");
1193 	free(base_path);
1194 	if (blob_orig_path) {
1195 		unlink(blob_orig_path);
1196 		free(blob_orig_path);
1197 	}
1198 	if (blob_deriv_path) {
1199 		unlink(blob_deriv_path);
1200 		free(blob_deriv_path);
1201 	}
1202 	free(id_str);
1203 	free(label_deriv);
1204 	free(parent);
1205 	return err;
1206 }
1207 
1208 static const struct got_error *
1209 create_fileindex_entry(struct got_fileindex_entry **new_iep,
1210     struct got_fileindex *fileindex, struct got_object_id *base_commit_id,
1211     int wt_fd, const char *path, struct got_object_id *blob_id)
1212 {
1213 	const struct got_error *err = NULL;
1214 	struct got_fileindex_entry *new_ie;
1215 
1216 	*new_iep = NULL;
1217 
1218 	err = got_fileindex_entry_alloc(&new_ie, path);
1219 	if (err)
1220 		return err;
1221 
1222 	err = got_fileindex_entry_update(new_ie, wt_fd, path,
1223 	    blob_id->sha1, base_commit_id->sha1, 1);
1224 	if (err)
1225 		goto done;
1226 
1227 	err = got_fileindex_entry_add(fileindex, new_ie);
1228 done:
1229 	if (err)
1230 		got_fileindex_entry_free(new_ie);
1231 	else
1232 		*new_iep = new_ie;
1233 	return err;
1234 }
1235 
1236 static mode_t
1237 get_ondisk_perms(int executable, mode_t st_mode)
1238 {
1239 	mode_t xbits = S_IXUSR;
1240 
1241 	if (executable) {
1242 		/* Map read bits to execute bits. */
1243 		if (st_mode & S_IRGRP)
1244 			xbits |= S_IXGRP;
1245 		if (st_mode & S_IROTH)
1246 			xbits |= S_IXOTH;
1247 		return st_mode | xbits;
1248 	}
1249 
1250 	return (st_mode & ~(S_IXUSR | S_IXGRP | S_IXOTH));
1251 }
1252 
1253 /* forward declaration */
1254 static const struct got_error *
1255 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1256     const char *path, mode_t te_mode, mode_t st_mode,
1257     struct got_blob_object *blob, int restoring_missing_file,
1258     int reverting_versioned_file, int installing_bad_symlink,
1259     int path_is_unversioned, struct got_repository *repo,
1260     got_worktree_checkout_cb progress_cb, void *progress_arg);
1261 
1262 /*
1263  * This function assumes that the provided symlink target points at a
1264  * safe location in the work tree!
1265  */
1266 static const struct got_error *
1267 replace_existing_symlink(int *did_something, const char *ondisk_path,
1268     const char *target_path, size_t target_len)
1269 {
1270 	const struct got_error *err = NULL;
1271 	ssize_t elen;
1272 	char etarget[PATH_MAX];
1273 	int fd;
1274 
1275 	*did_something = 0;
1276 
1277 	/*
1278 	 * "Bad" symlinks (those pointing outside the work tree or into the
1279 	 * .got directory) are installed in the work tree as a regular file
1280 	 * which contains the bad symlink target path.
1281 	 * The new symlink target has already been checked for safety by our
1282 	 * caller. If we can successfully open a regular file then we simply
1283 	 * replace this file with a symlink below.
1284 	 */
1285 	fd = open(ondisk_path, O_RDWR | O_EXCL | O_NOFOLLOW);
1286 	if (fd == -1) {
1287 		if (errno != ELOOP)
1288 			return got_error_from_errno2("open", ondisk_path);
1289 
1290 		/* We are updating an existing on-disk symlink. */
1291 		elen = readlink(ondisk_path, etarget, sizeof(etarget));
1292 		if (elen == -1)
1293 			return got_error_from_errno2("readlink", ondisk_path);
1294 
1295 		if (elen == target_len &&
1296 		    memcmp(etarget, target_path, target_len) == 0)
1297 			return NULL; /* nothing to do */
1298 	}
1299 
1300 	*did_something = 1;
1301 	err = update_symlink(ondisk_path, target_path, target_len);
1302 	if (fd != -1 && close(fd) == -1 && err == NULL)
1303 		err = got_error_from_errno2("close", ondisk_path);
1304 	return err;
1305 }
1306 
1307 static const struct got_error *
1308 is_bad_symlink_target(int *is_bad_symlink, const char *target_path,
1309     size_t target_len, const char *ondisk_path, const char *wtroot_path)
1310 {
1311 	const struct got_error *err = NULL;
1312 	char canonpath[PATH_MAX];
1313 	char *path_got = NULL;
1314 
1315 	*is_bad_symlink = 0;
1316 
1317 	if (target_len >= sizeof(canonpath)) {
1318 		*is_bad_symlink = 1;
1319 		return NULL;
1320 	}
1321 
1322 	/*
1323 	 * We do not use realpath(3) to resolve the symlink's target
1324 	 * path because we don't want to resolve symlinks recursively.
1325 	 * Instead we make the path absolute and then canonicalize it.
1326 	 * Relative symlink target lookup should begin at the directory
1327 	 * in which the blob object is being installed.
1328 	 */
1329 	if (!got_path_is_absolute(target_path)) {
1330 		char *abspath, *parent;
1331 		err = got_path_dirname(&parent, ondisk_path);
1332 		if (err)
1333 			return err;
1334 		if (asprintf(&abspath, "%s/%s",  parent, target_path) == -1) {
1335 			free(parent);
1336 			return got_error_from_errno("asprintf");
1337 		}
1338 		free(parent);
1339 		if (strlen(abspath) >= sizeof(canonpath)) {
1340 			err = got_error_path(abspath, GOT_ERR_BAD_PATH);
1341 			free(abspath);
1342 			return err;
1343 		}
1344 		err = got_canonpath(abspath, canonpath, sizeof(canonpath));
1345 		free(abspath);
1346 		if (err)
1347 			return err;
1348 	} else {
1349 		err = got_canonpath(target_path, canonpath, sizeof(canonpath));
1350 		if (err)
1351 			return err;
1352 	}
1353 
1354 	/* Only allow symlinks pointing at paths within the work tree. */
1355 	if (!got_path_is_child(canonpath, wtroot_path, strlen(wtroot_path))) {
1356 		*is_bad_symlink = 1;
1357 		return NULL;
1358 	}
1359 
1360 	/* Do not allow symlinks pointing into the .got directory. */
1361 	if (asprintf(&path_got, "%s/%s", wtroot_path,
1362 	    GOT_WORKTREE_GOT_DIR) == -1)
1363 		return got_error_from_errno("asprintf");
1364 	if (got_path_is_child(canonpath, path_got, strlen(path_got)))
1365 		*is_bad_symlink = 1;
1366 
1367 	free(path_got);
1368 	return NULL;
1369 }
1370 
1371 static const struct got_error *
1372 install_symlink(int *is_bad_symlink, struct got_worktree *worktree,
1373     const char *ondisk_path, const char *path, struct got_blob_object *blob,
1374     int restoring_missing_file, int reverting_versioned_file,
1375     int path_is_unversioned, struct got_repository *repo,
1376     got_worktree_checkout_cb progress_cb, void *progress_arg)
1377 {
1378 	const struct got_error *err = NULL;
1379 	char target_path[PATH_MAX];
1380 	size_t len, target_len = 0;
1381 	char *path_got = NULL;
1382 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1383 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1384 
1385 	*is_bad_symlink = 0;
1386 
1387 	/* 
1388 	 * Blob object content specifies the target path of the link.
1389 	 * If a symbolic link cannot be installed we instead create
1390 	 * a regular file which contains the link target path stored
1391 	 * in the blob object.
1392 	 */
1393 	do {
1394 		err = got_object_blob_read_block(&len, blob);
1395 		if (len + target_len >= sizeof(target_path)) {
1396 			/* Path too long; install as a regular file. */
1397 			*is_bad_symlink = 1;
1398 			got_object_blob_rewind(blob);
1399 			return install_blob(worktree, ondisk_path, path,
1400 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1401 			    restoring_missing_file, reverting_versioned_file,
1402 			    1, path_is_unversioned, repo, progress_cb,
1403 			    progress_arg);
1404 		}
1405 		if (len > 0) {
1406 			/* Skip blob object header first time around. */
1407 			memcpy(target_path + target_len, buf + hdrlen,
1408 			    len - hdrlen);
1409 			target_len += len - hdrlen;
1410 			hdrlen = 0;
1411 		}
1412 	} while (len != 0);
1413 	target_path[target_len] = '\0';
1414 
1415 	err = is_bad_symlink_target(is_bad_symlink, target_path, target_len,
1416 	    ondisk_path, worktree->root_path);
1417 	if (err)
1418 		return err;
1419 
1420 	if (*is_bad_symlink) {
1421 		/* install as a regular file */
1422 		got_object_blob_rewind(blob);
1423 		err = install_blob(worktree, ondisk_path, path,
1424 		    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1425 		    restoring_missing_file, reverting_versioned_file, 1,
1426 		    path_is_unversioned, repo, progress_cb, progress_arg);
1427 		goto done;
1428 	}
1429 
1430 	if (symlink(target_path, ondisk_path) == -1) {
1431 		if (errno == EEXIST) {
1432 			int symlink_replaced;
1433 			if (path_is_unversioned) {
1434 				err = (*progress_cb)(progress_arg,
1435 				    GOT_STATUS_UNVERSIONED, path);
1436 				goto done;
1437 			}
1438 			err = replace_existing_symlink(&symlink_replaced,
1439 			    ondisk_path, target_path, target_len);
1440 			if (err)
1441 				goto done;
1442 			if (progress_cb) {
1443 				if (symlink_replaced) {
1444 					err = (*progress_cb)(progress_arg,
1445 					    reverting_versioned_file ?
1446 					    GOT_STATUS_REVERT :
1447 					    GOT_STATUS_UPDATE, path);
1448 				} else {
1449 					err = (*progress_cb)(progress_arg,
1450 					    GOT_STATUS_EXISTS, path);
1451 				}
1452 			}
1453 			goto done; /* Nothing else to do. */
1454 		}
1455 
1456 		if (errno == ENOENT) {
1457 			char *parent;
1458 			err = got_path_dirname(&parent, ondisk_path);
1459 			if (err)
1460 				goto done;
1461 			err = add_dir_on_disk(worktree, parent);
1462 			free(parent);
1463 			if (err)
1464 				goto done;
1465 			/*
1466 			 * Retry, and fall through to error handling
1467 			 * below if this second attempt fails.
1468 			 */
1469 			if (symlink(target_path, ondisk_path) != -1) {
1470 				err = NULL; /* success */
1471 				goto done;
1472 			}
1473 		}
1474 
1475 		/* Handle errors from first or second creation attempt. */
1476 		if (errno == ENAMETOOLONG) {
1477 			/* bad target path; install as a regular file */
1478 			*is_bad_symlink = 1;
1479 			got_object_blob_rewind(blob);
1480 			err = install_blob(worktree, ondisk_path, path,
1481 			    GOT_DEFAULT_FILE_MODE, GOT_DEFAULT_FILE_MODE, blob,
1482 			    restoring_missing_file, reverting_versioned_file, 1,
1483 			    path_is_unversioned, repo,
1484 			    progress_cb, progress_arg);
1485 		} else if (errno == ENOTDIR) {
1486 			err = got_error_path(ondisk_path,
1487 			    GOT_ERR_FILE_OBSTRUCTED);
1488 		} else {
1489 			err = got_error_from_errno3("symlink",
1490 			    target_path, ondisk_path);
1491 		}
1492 	} else if (progress_cb)
1493 		err = (*progress_cb)(progress_arg, reverting_versioned_file ?
1494 		    GOT_STATUS_REVERT : GOT_STATUS_ADD, path);
1495 done:
1496 	free(path_got);
1497 	return err;
1498 }
1499 
1500 static const struct got_error *
1501 install_blob(struct got_worktree *worktree, const char *ondisk_path,
1502     const char *path, mode_t te_mode, mode_t st_mode,
1503     struct got_blob_object *blob, int restoring_missing_file,
1504     int reverting_versioned_file, int installing_bad_symlink,
1505     int path_is_unversioned, struct got_repository *repo,
1506     got_worktree_checkout_cb progress_cb, void *progress_arg)
1507 {
1508 	const struct got_error *err = NULL;
1509 	int fd = -1;
1510 	size_t len, hdrlen;
1511 	int update = 0;
1512 	char *tmppath = NULL;
1513 
1514 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
1515 	    GOT_DEFAULT_FILE_MODE);
1516 	if (fd == -1) {
1517 		if (errno == ENOENT) {
1518 			char *parent;
1519 			err = got_path_dirname(&parent, path);
1520 			if (err)
1521 				return err;
1522 			err = add_dir_on_disk(worktree, parent);
1523 			free(parent);
1524 			if (err)
1525 				return err;
1526 			fd = open(ondisk_path,
1527 			    O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
1528 			    GOT_DEFAULT_FILE_MODE);
1529 			if (fd == -1)
1530 				return got_error_from_errno2("open",
1531 				    ondisk_path);
1532 		} else if (errno == EEXIST) {
1533 			if (path_is_unversioned) {
1534 				err = (*progress_cb)(progress_arg,
1535 				    GOT_STATUS_UNVERSIONED, path);
1536 				goto done;
1537 			}
1538 			if (!(S_ISLNK(st_mode) && S_ISREG(te_mode)) &&
1539 			    !S_ISREG(st_mode) && !installing_bad_symlink) {
1540 				/* TODO file is obstructed; do something */
1541 				err = got_error_path(ondisk_path,
1542 				    GOT_ERR_FILE_OBSTRUCTED);
1543 				goto done;
1544 			} else {
1545 				err = got_opentemp_named_fd(&tmppath, &fd,
1546 				    ondisk_path);
1547 				if (err)
1548 					goto done;
1549 				update = 1;
1550 			}
1551 		} else
1552 			return got_error_from_errno2("open", ondisk_path);
1553 	}
1554 
1555 	if (fchmod(fd, get_ondisk_perms(te_mode & S_IXUSR, st_mode)) == -1) {
1556 		err = got_error_from_errno2("fchmod",
1557 		    update ? tmppath : ondisk_path);
1558 		goto done;
1559 	}
1560 
1561 	if (progress_cb) {
1562 		if (restoring_missing_file)
1563 			err = (*progress_cb)(progress_arg, GOT_STATUS_MISSING,
1564 			    path);
1565 		else if (reverting_versioned_file)
1566 			err = (*progress_cb)(progress_arg, GOT_STATUS_REVERT,
1567 			    path);
1568 		else
1569 			err = (*progress_cb)(progress_arg,
1570 			    update ? GOT_STATUS_UPDATE : GOT_STATUS_ADD, path);
1571 		if (err)
1572 			goto done;
1573 	}
1574 
1575 	hdrlen = got_object_blob_get_hdrlen(blob);
1576 	do {
1577 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
1578 		err = got_object_blob_read_block(&len, blob);
1579 		if (err)
1580 			break;
1581 		if (len > 0) {
1582 			/* Skip blob object header first time around. */
1583 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
1584 			if (outlen == -1) {
1585 				err = got_error_from_errno("write");
1586 				goto done;
1587 			} else if (outlen != len - hdrlen) {
1588 				err = got_error(GOT_ERR_IO);
1589 				goto done;
1590 			}
1591 			hdrlen = 0;
1592 		}
1593 	} while (len != 0);
1594 
1595 	if (fsync(fd) != 0) {
1596 		err = got_error_from_errno("fsync");
1597 		goto done;
1598 	}
1599 
1600 	if (update) {
1601 		if (S_ISLNK(st_mode) && unlink(ondisk_path) == -1) {
1602 			err = got_error_from_errno2("unlink", ondisk_path);
1603 			goto done;
1604 		}
1605 		if (rename(tmppath, ondisk_path) != 0) {
1606 			err = got_error_from_errno3("rename", tmppath,
1607 			    ondisk_path);
1608 			goto done;
1609 		}
1610 		free(tmppath);
1611 		tmppath = NULL;
1612 	}
1613 
1614 done:
1615 	if (fd != -1 && close(fd) == -1 && err == NULL)
1616 		err = got_error_from_errno("close");
1617 	if (tmppath != NULL && unlink(tmppath) == -1 && err == NULL)
1618 		err = got_error_from_errno2("unlink", tmppath);
1619 	free(tmppath);
1620 	return err;
1621 }
1622 
1623 /* Upgrade STATUS_MODIFY to STATUS_CONFLICT if a conflict marker is found. */
1624 static const struct got_error *
1625 get_modified_file_content_status(unsigned char *status, FILE *f)
1626 {
1627 	const struct got_error *err = NULL;
1628 	const char *markers[3] = {
1629 		GOT_DIFF_CONFLICT_MARKER_BEGIN,
1630 		GOT_DIFF_CONFLICT_MARKER_SEP,
1631 		GOT_DIFF_CONFLICT_MARKER_END
1632 	};
1633 	int i = 0;
1634 	char *line = NULL;
1635 	size_t linesize = 0;
1636 	ssize_t linelen;
1637 
1638 	while (*status == GOT_STATUS_MODIFY) {
1639 		linelen = getline(&line, &linesize, f);
1640 		if (linelen == -1) {
1641 			if (feof(f))
1642 				break;
1643 			err = got_ferror(f, GOT_ERR_IO);
1644 			break;
1645 		}
1646 
1647 		if (strncmp(line, markers[i], strlen(markers[i])) == 0) {
1648 			if (strcmp(markers[i], GOT_DIFF_CONFLICT_MARKER_END)
1649 			    == 0)
1650 				*status = GOT_STATUS_CONFLICT;
1651 			else
1652 				i++;
1653 		}
1654 	}
1655 	free(line);
1656 
1657 	return err;
1658 }
1659 
1660 static int
1661 xbit_differs(struct got_fileindex_entry *ie, uint16_t st_mode)
1662 {
1663 	mode_t ie_mode = got_fileindex_perms_to_st(ie);
1664 	return ((ie_mode & S_IXUSR) != (st_mode & S_IXUSR));
1665 }
1666 
1667 static int
1668 stat_info_differs(struct got_fileindex_entry *ie, struct stat *sb)
1669 {
1670 	return !(ie->ctime_sec == sb->st_ctim.tv_sec &&
1671 	    ie->ctime_nsec == sb->st_ctim.tv_nsec &&
1672 	    ie->mtime_sec == sb->st_mtim.tv_sec &&
1673 	    ie->mtime_nsec == sb->st_mtim.tv_nsec &&
1674 	    ie->size == (sb->st_size & 0xffffffff) &&
1675 	    !xbit_differs(ie, sb->st_mode));
1676 }
1677 
1678 static unsigned char
1679 get_staged_status(struct got_fileindex_entry *ie)
1680 {
1681 	switch (got_fileindex_entry_stage_get(ie)) {
1682 	case GOT_FILEIDX_STAGE_ADD:
1683 		return GOT_STATUS_ADD;
1684 	case GOT_FILEIDX_STAGE_DELETE:
1685 		return GOT_STATUS_DELETE;
1686 	case GOT_FILEIDX_STAGE_MODIFY:
1687 		return GOT_STATUS_MODIFY;
1688 	default:
1689 		return GOT_STATUS_NO_CHANGE;
1690 	}
1691 }
1692 
1693 static const struct got_error *
1694 get_symlink_modification_status(unsigned char *status,
1695     struct got_fileindex_entry *ie, const char *abspath,
1696     int dirfd, const char *de_name, struct got_blob_object *blob)
1697 {
1698 	const struct got_error *err = NULL;
1699 	char target_path[PATH_MAX];
1700 	char etarget[PATH_MAX];
1701 	ssize_t elen;
1702 	size_t len, target_len = 0;
1703 	const uint8_t *buf = got_object_blob_get_read_buf(blob);
1704 	size_t hdrlen = got_object_blob_get_hdrlen(blob);
1705 
1706 	*status = GOT_STATUS_NO_CHANGE;
1707 
1708 	/* Blob object content specifies the target path of the link. */
1709 	do {
1710 		err = got_object_blob_read_block(&len, blob);
1711 		if (err)
1712 			return err;
1713 		if (len + target_len >= sizeof(target_path)) {
1714 			/*
1715 			 * Should not happen. The blob contents were OK
1716 			 * when this symlink was installed.
1717 			 */
1718 			return got_error(GOT_ERR_NO_SPACE);
1719 		}
1720 		if (len > 0) {
1721 			/* Skip blob object header first time around. */
1722 			memcpy(target_path + target_len, buf + hdrlen,
1723 			    len - hdrlen);
1724 			target_len += len - hdrlen;
1725 			hdrlen = 0;
1726 		}
1727 	} while (len != 0);
1728 	target_path[target_len] = '\0';
1729 
1730 	if (dirfd != -1) {
1731 		elen = readlinkat(dirfd, de_name, etarget, sizeof(etarget));
1732 		if (elen == -1)
1733 			return got_error_from_errno2("readlinkat", abspath);
1734 	} else {
1735 		elen = readlink(abspath, etarget, sizeof(etarget));
1736 		if (elen == -1)
1737 			return got_error_from_errno2("readlink", abspath);
1738 	}
1739 
1740 	if (elen != target_len || memcmp(etarget, target_path, target_len) != 0)
1741 		*status = GOT_STATUS_MODIFY;
1742 
1743 	return NULL;
1744 }
1745 
1746 static const struct got_error *
1747 get_file_status(unsigned char *status, struct stat *sb,
1748     struct got_fileindex_entry *ie, const char *abspath,
1749     int dirfd, const char *de_name, struct got_repository *repo)
1750 {
1751 	const struct got_error *err = NULL;
1752 	struct got_object_id id;
1753 	size_t hdrlen;
1754 	int fd = -1;
1755 	FILE *f = NULL;
1756 	uint8_t fbuf[8192];
1757 	struct got_blob_object *blob = NULL;
1758 	size_t flen, blen;
1759 	unsigned char staged_status = get_staged_status(ie);
1760 
1761 	*status = GOT_STATUS_NO_CHANGE;
1762 	memset(sb, 0, sizeof(*sb));
1763 
1764 	/*
1765 	 * Whenever the caller provides a directory descriptor and a
1766 	 * directory entry name for the file, use them! This prevents
1767 	 * race conditions if filesystem paths change beneath our feet.
1768 	 */
1769 	if (dirfd != -1) {
1770 		if (fstatat(dirfd, de_name, sb, AT_SYMLINK_NOFOLLOW) == -1) {
1771 			if (errno == ENOENT) {
1772 				if (got_fileindex_entry_has_file_on_disk(ie))
1773 					*status = GOT_STATUS_MISSING;
1774 				else
1775 					*status = GOT_STATUS_DELETE;
1776 				goto done;
1777 			}
1778 			err = got_error_from_errno2("fstatat", abspath);
1779 			goto done;
1780 		}
1781 	} else {
1782 		fd = open(abspath, O_RDONLY | O_NOFOLLOW);
1783 		if (fd == -1 && errno != ENOENT && errno != ELOOP)
1784 			return got_error_from_errno2("open", abspath);
1785 		else if (fd == -1 && errno == ELOOP) {
1786 			if (lstat(abspath, sb) == -1)
1787 				return got_error_from_errno2("lstat", abspath);
1788 		} else if (fd == -1 || fstat(fd, sb) == -1) {
1789 			if (errno == ENOENT) {
1790 				if (got_fileindex_entry_has_file_on_disk(ie))
1791 					*status = GOT_STATUS_MISSING;
1792 				else
1793 					*status = GOT_STATUS_DELETE;
1794 				goto done;
1795 			}
1796 			err = got_error_from_errno2("fstat", abspath);
1797 			goto done;
1798 		}
1799 	}
1800 
1801 	if (!S_ISREG(sb->st_mode) && !S_ISLNK(sb->st_mode)) {
1802 		*status = GOT_STATUS_OBSTRUCTED;
1803 		goto done;
1804 	}
1805 
1806 	if (!got_fileindex_entry_has_file_on_disk(ie)) {
1807 		*status = GOT_STATUS_DELETE;
1808 		goto done;
1809 	} else if (!got_fileindex_entry_has_blob(ie) &&
1810 	    staged_status != GOT_STATUS_ADD) {
1811 		*status = GOT_STATUS_ADD;
1812 		goto done;
1813 	}
1814 
1815 	if (!stat_info_differs(ie, sb))
1816 		goto done;
1817 
1818 	if (S_ISLNK(sb->st_mode) &&
1819 	    got_fileindex_entry_filetype_get(ie) != GOT_FILEIDX_MODE_SYMLINK) {
1820 		*status = GOT_STATUS_MODIFY;
1821 		goto done;
1822 	}
1823 
1824 	if (staged_status == GOT_STATUS_MODIFY ||
1825 	    staged_status == GOT_STATUS_ADD)
1826 		memcpy(id.sha1, ie->staged_blob_sha1, sizeof(id.sha1));
1827 	else
1828 		memcpy(id.sha1, ie->blob_sha1, sizeof(id.sha1));
1829 
1830 	err = got_object_open_as_blob(&blob, repo, &id, sizeof(fbuf));
1831 	if (err)
1832 		goto done;
1833 
1834 	if (S_ISLNK(sb->st_mode)) {
1835 		err = get_symlink_modification_status(status, ie,
1836 		    abspath, dirfd, de_name, blob);
1837 		goto done;
1838 	}
1839 
1840 	if (dirfd != -1) {
1841 		fd = openat(dirfd, de_name, O_RDONLY | O_NOFOLLOW);
1842 		if (fd == -1) {
1843 			err = got_error_from_errno2("openat", abspath);
1844 			goto done;
1845 		}
1846 	}
1847 
1848 	f = fdopen(fd, "r");
1849 	if (f == NULL) {
1850 		err = got_error_from_errno2("fdopen", abspath);
1851 		goto done;
1852 	}
1853 	fd = -1;
1854 	hdrlen = got_object_blob_get_hdrlen(blob);
1855 	for (;;) {
1856 		const uint8_t *bbuf = got_object_blob_get_read_buf(blob);
1857 		err = got_object_blob_read_block(&blen, blob);
1858 		if (err)
1859 			goto done;
1860 		/* Skip length of blob object header first time around. */
1861 		flen = fread(fbuf, 1, sizeof(fbuf) - hdrlen, f);
1862 		if (flen == 0 && ferror(f)) {
1863 			err = got_error_from_errno("fread");
1864 			goto done;
1865 		}
1866 		if (blen - hdrlen == 0) {
1867 			if (flen != 0)
1868 				*status = GOT_STATUS_MODIFY;
1869 			break;
1870 		} else if (flen == 0) {
1871 			if (blen - hdrlen != 0)
1872 				*status = GOT_STATUS_MODIFY;
1873 			break;
1874 		} else if (blen - hdrlen == flen) {
1875 			/* Skip blob object header first time around. */
1876 			if (memcmp(bbuf + hdrlen, fbuf, flen) != 0) {
1877 				*status = GOT_STATUS_MODIFY;
1878 				break;
1879 			}
1880 		} else {
1881 			*status = GOT_STATUS_MODIFY;
1882 			break;
1883 		}
1884 		hdrlen = 0;
1885 	}
1886 
1887 	if (*status == GOT_STATUS_MODIFY) {
1888 		rewind(f);
1889 		err = get_modified_file_content_status(status, f);
1890 	} else if (xbit_differs(ie, sb->st_mode))
1891 		*status = GOT_STATUS_MODE_CHANGE;
1892 done:
1893 	if (blob)
1894 		got_object_blob_close(blob);
1895 	if (f != NULL && fclose(f) == EOF && err == NULL)
1896 		err = got_error_from_errno2("fclose", abspath);
1897 	if (fd != -1 && close(fd) == -1 && err == NULL)
1898 		err = got_error_from_errno2("close", abspath);
1899 	return err;
1900 }
1901 
1902 /*
1903  * Update timestamps in the file index if a file is unmodified and
1904  * we had to run a full content comparison to find out.
1905  */
1906 static const struct got_error *
1907 sync_timestamps(int wt_fd, const char *path, unsigned char status,
1908     struct got_fileindex_entry *ie, struct stat *sb)
1909 {
1910 	if (status == GOT_STATUS_NO_CHANGE && stat_info_differs(ie, sb))
1911 		return got_fileindex_entry_update(ie, wt_fd, path,
1912 		    ie->blob_sha1, ie->commit_sha1, 1);
1913 
1914 	return NULL;
1915 }
1916 
1917 static const struct got_error *
1918 update_blob(struct got_worktree *worktree,
1919     struct got_fileindex *fileindex, struct got_fileindex_entry *ie,
1920     struct got_tree_entry *te, const char *path,
1921     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
1922     void *progress_arg)
1923 {
1924 	const struct got_error *err = NULL;
1925 	struct got_blob_object *blob = NULL;
1926 	char *ondisk_path;
1927 	unsigned char status = GOT_STATUS_NO_CHANGE;
1928 	struct stat sb;
1929 
1930 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, path) == -1)
1931 		return got_error_from_errno("asprintf");
1932 
1933 	if (ie) {
1934 		if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE) {
1935 			err = got_error_path(ie->path, GOT_ERR_FILE_STAGED);
1936 			goto done;
1937 		}
1938 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
1939 		    repo);
1940 		if (err)
1941 			goto done;
1942 		if (status == GOT_STATUS_MISSING || status == GOT_STATUS_DELETE)
1943 			sb.st_mode = got_fileindex_perms_to_st(ie);
1944 	} else {
1945 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
1946 		status = GOT_STATUS_UNVERSIONED;
1947 	}
1948 
1949 	if (status == GOT_STATUS_OBSTRUCTED) {
1950 		err = (*progress_cb)(progress_arg, status, path);
1951 		goto done;
1952 	}
1953 	if (status == GOT_STATUS_CONFLICT) {
1954 		err = (*progress_cb)(progress_arg, GOT_STATUS_CANNOT_UPDATE,
1955 		    path);
1956 		goto done;
1957 	}
1958 
1959 	if (ie && status != GOT_STATUS_MISSING && S_ISREG(sb.st_mode) &&
1960 	    (S_ISLNK(te->mode) ||
1961 	    (te->mode & S_IXUSR) == (sb.st_mode & S_IXUSR))) {
1962 		/*
1963 		 * This is a regular file or an installed bad symlink.
1964 		 * If the file index indicates that this file is already
1965 		 * up-to-date with respect to the repository we can skip
1966 		 * updating contents of this file.
1967 		 */
1968 		if (got_fileindex_entry_has_commit(ie) &&
1969 		    memcmp(ie->commit_sha1, worktree->base_commit_id->sha1,
1970 		    SHA1_DIGEST_LENGTH) == 0) {
1971 			/* Same commit. */
1972 			err = sync_timestamps(worktree->root_fd,
1973 			    path, status, ie, &sb);
1974 			if (err)
1975 				goto done;
1976 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1977 			    path);
1978 			goto done;
1979 		}
1980 		if (got_fileindex_entry_has_blob(ie) &&
1981 		    memcmp(ie->blob_sha1, te->id.sha1,
1982 		    SHA1_DIGEST_LENGTH) == 0) {
1983 			/* Different commit but the same blob. */
1984 			err = sync_timestamps(worktree->root_fd,
1985 			    path, status, ie, &sb);
1986 			if (err)
1987 				goto done;
1988 			err = (*progress_cb)(progress_arg, GOT_STATUS_EXISTS,
1989 			    path);
1990 			goto done;
1991 		}
1992 	}
1993 
1994 	err = got_object_open_as_blob(&blob, repo, &te->id, 8192);
1995 	if (err)
1996 		goto done;
1997 
1998 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_ADD) {
1999 		int update_timestamps;
2000 		struct got_blob_object *blob2 = NULL;
2001 		char *label_orig = NULL;
2002 		if (got_fileindex_entry_has_blob(ie)) {
2003 			struct got_object_id id2;
2004 			memcpy(id2.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
2005 			err = got_object_open_as_blob(&blob2, repo, &id2, 8192);
2006 			if (err)
2007 				goto done;
2008 		}
2009 		if (got_fileindex_entry_has_commit(ie)) {
2010 			char id_str[SHA1_DIGEST_STRING_LENGTH];
2011 			if (got_sha1_digest_to_str(ie->commit_sha1, id_str,
2012 			    sizeof(id_str)) == NULL) {
2013 				err = got_error_path(id_str,
2014 				    GOT_ERR_BAD_OBJ_ID_STR);
2015 				goto done;
2016 			}
2017 			if (asprintf(&label_orig, "%s: commit %s",
2018 			    GOT_MERGE_LABEL_BASE, id_str) == -1) {
2019 				err = got_error_from_errno("asprintf");
2020 				goto done;
2021 			}
2022 		}
2023 		if (S_ISLNK(te->mode) && S_ISLNK(sb.st_mode)) {
2024 			char *link_target;
2025 			err = got_object_blob_read_to_str(&link_target, blob);
2026 			if (err)
2027 				goto done;
2028 			err = merge_symlink(worktree, blob2, ondisk_path, path,
2029 			    label_orig, link_target, worktree->base_commit_id,
2030 			    repo, progress_cb, progress_arg);
2031 			free(link_target);
2032 		} else {
2033 			err = merge_blob(&update_timestamps, worktree, blob2,
2034 			    ondisk_path, path, sb.st_mode, label_orig, blob,
2035 			    worktree->base_commit_id, repo,
2036 			    progress_cb, progress_arg);
2037 		}
2038 		free(label_orig);
2039 		if (blob2)
2040 			got_object_blob_close(blob2);
2041 		if (err)
2042 			goto done;
2043 		/*
2044 		 * Do not update timestamps of files with local changes.
2045 		 * Otherwise, a future status walk would treat them as
2046 		 * unmodified files again.
2047 		 */
2048 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2049 		    blob->id.sha1, worktree->base_commit_id->sha1,
2050 		    update_timestamps);
2051 	} else if (status == GOT_STATUS_MODE_CHANGE) {
2052 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2053 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
2054 	} else if (status == GOT_STATUS_DELETE) {
2055 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, path);
2056 		if (err)
2057 			goto done;
2058 		err = got_fileindex_entry_update(ie, worktree->root_fd, path,
2059 		    blob->id.sha1, worktree->base_commit_id->sha1, 0);
2060 		if (err)
2061 			goto done;
2062 	} else {
2063 		int is_bad_symlink = 0;
2064 		if (S_ISLNK(te->mode)) {
2065 			err = install_symlink(&is_bad_symlink, worktree,
2066 			    ondisk_path, path, blob,
2067 			    status == GOT_STATUS_MISSING, 0,
2068 			    status == GOT_STATUS_UNVERSIONED, repo,
2069 			    progress_cb, progress_arg);
2070 		} else {
2071 			err = install_blob(worktree, ondisk_path, path,
2072 			    te->mode, sb.st_mode, blob,
2073 			    status == GOT_STATUS_MISSING, 0, 0,
2074 			    status == GOT_STATUS_UNVERSIONED, repo,
2075 			    progress_cb, progress_arg);
2076 		}
2077 		if (err)
2078 			goto done;
2079 
2080 		if (ie) {
2081 			err = got_fileindex_entry_update(ie,
2082 			    worktree->root_fd, path, blob->id.sha1,
2083 			    worktree->base_commit_id->sha1, 1);
2084 		} else {
2085 			err = create_fileindex_entry(&ie, fileindex,
2086 			    worktree->base_commit_id, worktree->root_fd, path,
2087 			    &blob->id);
2088 		}
2089 		if (err)
2090 			goto done;
2091 
2092 		if (is_bad_symlink) {
2093 			got_fileindex_entry_filetype_set(ie,
2094 			    GOT_FILEIDX_MODE_BAD_SYMLINK);
2095 		}
2096 	}
2097 	got_object_blob_close(blob);
2098 done:
2099 	free(ondisk_path);
2100 	return err;
2101 }
2102 
2103 static const struct got_error *
2104 remove_ondisk_file(const char *root_path, const char *path)
2105 {
2106 	const struct got_error *err = NULL;
2107 	char *ondisk_path = NULL;
2108 
2109 	if (asprintf(&ondisk_path, "%s/%s", root_path, path) == -1)
2110 		return got_error_from_errno("asprintf");
2111 
2112 	if (unlink(ondisk_path) == -1) {
2113 		if (errno != ENOENT)
2114 			err = got_error_from_errno2("unlink", ondisk_path);
2115 	} else {
2116 		size_t root_len = strlen(root_path);
2117 		do {
2118 			char *parent;
2119 			err = got_path_dirname(&parent, ondisk_path);
2120 			if (err)
2121 				break;
2122 			free(ondisk_path);
2123 			ondisk_path = parent;
2124 			if (rmdir(ondisk_path) == -1) {
2125 				if (errno != ENOTEMPTY)
2126 					err = got_error_from_errno2("rmdir",
2127 					    ondisk_path);
2128 				break;
2129 			}
2130 		} while (got_path_cmp(ondisk_path, root_path,
2131 		    strlen(ondisk_path), root_len) != 0);
2132 	}
2133 	free(ondisk_path);
2134 	return err;
2135 }
2136 
2137 static const struct got_error *
2138 delete_blob(struct got_worktree *worktree, struct got_fileindex *fileindex,
2139     struct got_fileindex_entry *ie, struct got_repository *repo,
2140     got_worktree_checkout_cb progress_cb, void *progress_arg)
2141 {
2142 	const struct got_error *err = NULL;
2143 	unsigned char status;
2144 	struct stat sb;
2145 	char *ondisk_path;
2146 
2147 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
2148 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
2149 
2150 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path, ie->path)
2151 	    == -1)
2152 		return got_error_from_errno("asprintf");
2153 
2154 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, repo);
2155 	if (err)
2156 		goto done;
2157 
2158 	if (S_ISLNK(sb.st_mode) && status != GOT_STATUS_NO_CHANGE) {
2159 		char ondisk_target[PATH_MAX];
2160 		ssize_t ondisk_len = readlink(ondisk_path, ondisk_target,
2161 		    sizeof(ondisk_target));
2162 		if (ondisk_len == -1) {
2163 			err = got_error_from_errno2("readlink", ondisk_path);
2164 			goto done;
2165 		}
2166 		ondisk_target[ondisk_len] = '\0';
2167 		err = install_symlink_conflict(NULL, worktree->base_commit_id,
2168 		    NULL, NULL, /* XXX pass common ancestor info? */
2169 		    ondisk_target, ondisk_path);
2170 		if (err)
2171 			goto done;
2172 		err = (*progress_cb)(progress_arg, GOT_STATUS_CONFLICT,
2173 		    ie->path);
2174 		goto done;
2175 	}
2176 
2177 	if (status == GOT_STATUS_MODIFY || status == GOT_STATUS_CONFLICT ||
2178 	    status == GOT_STATUS_ADD) {
2179 		err = (*progress_cb)(progress_arg, GOT_STATUS_MERGE, ie->path);
2180 		if (err)
2181 			goto done;
2182 		/*
2183 		 * Preserve the working file and change the deleted blob's
2184 		 * entry into a schedule-add entry.
2185 		 */
2186 		err = got_fileindex_entry_update(ie, worktree->root_fd,
2187 		    ie->path, NULL, NULL, 0);
2188 	} else {
2189 		err = (*progress_cb)(progress_arg, GOT_STATUS_DELETE, ie->path);
2190 		if (err)
2191 			goto done;
2192 		if (status == GOT_STATUS_NO_CHANGE) {
2193 			err = remove_ondisk_file(worktree->root_path, ie->path);
2194 			if (err)
2195 				goto done;
2196 		}
2197 		got_fileindex_entry_remove(fileindex, ie);
2198 	}
2199 done:
2200 	free(ondisk_path);
2201 	return err;
2202 }
2203 
2204 struct diff_cb_arg {
2205     struct got_fileindex *fileindex;
2206     struct got_worktree *worktree;
2207     struct got_repository *repo;
2208     got_worktree_checkout_cb progress_cb;
2209     void *progress_arg;
2210     got_cancel_cb cancel_cb;
2211     void *cancel_arg;
2212 };
2213 
2214 static const struct got_error *
2215 diff_old_new(void *arg, struct got_fileindex_entry *ie,
2216     struct got_tree_entry *te, const char *parent_path)
2217 {
2218 	struct diff_cb_arg *a = arg;
2219 
2220 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2221 		return got_error(GOT_ERR_CANCELLED);
2222 
2223 	return update_blob(a->worktree, a->fileindex, ie, te,
2224 	    ie->path, a->repo, a->progress_cb, a->progress_arg);
2225 }
2226 
2227 static const struct got_error *
2228 diff_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
2229 {
2230 	struct diff_cb_arg *a = arg;
2231 
2232 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2233 		return got_error(GOT_ERR_CANCELLED);
2234 
2235 	return delete_blob(a->worktree, a->fileindex, ie,
2236 	    a->repo, a->progress_cb, a->progress_arg);
2237 }
2238 
2239 static const struct got_error *
2240 diff_new(void *arg, struct got_tree_entry *te, const char *parent_path)
2241 {
2242 	struct diff_cb_arg *a = arg;
2243 	const struct got_error *err;
2244 	char *path;
2245 
2246 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
2247 		return got_error(GOT_ERR_CANCELLED);
2248 
2249 	if (got_object_tree_entry_is_submodule(te))
2250 		return NULL;
2251 
2252 	if (asprintf(&path, "%s%s%s", parent_path,
2253 	    parent_path[0] ? "/" : "", te->name)
2254 	    == -1)
2255 		return got_error_from_errno("asprintf");
2256 
2257 	if (S_ISDIR(te->mode))
2258 		err = add_dir_on_disk(a->worktree, path);
2259 	else
2260 		err = update_blob(a->worktree, a->fileindex, NULL, te, path,
2261 		    a->repo, a->progress_cb, a->progress_arg);
2262 
2263 	free(path);
2264 	return err;
2265 }
2266 
2267 const struct got_error *
2268 got_worktree_get_uuid(char **uuidstr, struct got_worktree *worktree)
2269 {
2270 	uint32_t uuid_status;
2271 
2272 	uuid_to_string(&worktree->uuid, uuidstr, &uuid_status);
2273 	if (uuid_status != uuid_s_ok) {
2274 		*uuidstr = NULL;
2275 		return got_error_uuid(uuid_status, "uuid_to_string");
2276 	}
2277 
2278 	return NULL;
2279 }
2280 
2281 static const struct got_error *
2282 get_ref_name(char **refname, struct got_worktree *worktree, const char *prefix)
2283 {
2284 	const struct got_error *err = NULL;
2285 	char *uuidstr = NULL;
2286 
2287 	*refname = NULL;
2288 
2289 	err = got_worktree_get_uuid(&uuidstr, worktree);
2290 	if (err)
2291 		return err;
2292 
2293 	if (asprintf(refname, "%s-%s", prefix, uuidstr) == -1) {
2294 		err = got_error_from_errno("asprintf");
2295 		*refname = NULL;
2296 	}
2297 	free(uuidstr);
2298 	return err;
2299 }
2300 
2301 const struct got_error *
2302 got_worktree_get_base_ref_name(char **refname, struct got_worktree *worktree)
2303 {
2304 	return get_ref_name(refname, worktree, GOT_WORKTREE_BASE_REF_PREFIX);
2305 }
2306 
2307 static const struct got_error *
2308 get_rebase_tmp_ref_name(char **refname, struct got_worktree *worktree)
2309 {
2310 	return get_ref_name(refname, worktree,
2311 	    GOT_WORKTREE_REBASE_TMP_REF_PREFIX);
2312 }
2313 
2314 static const struct got_error *
2315 get_newbase_symref_name(char **refname, struct got_worktree *worktree)
2316 {
2317 	return get_ref_name(refname, worktree, GOT_WORKTREE_NEWBASE_REF_PREFIX);
2318 }
2319 
2320 static const struct got_error *
2321 get_rebase_branch_symref_name(char **refname, struct got_worktree *worktree)
2322 {
2323 	return get_ref_name(refname, worktree,
2324 	    GOT_WORKTREE_REBASE_BRANCH_REF_PREFIX);
2325 }
2326 
2327 static const struct got_error *
2328 get_rebase_commit_ref_name(char **refname, struct got_worktree *worktree)
2329 {
2330 	return get_ref_name(refname, worktree,
2331 	    GOT_WORKTREE_REBASE_COMMIT_REF_PREFIX);
2332 }
2333 
2334 static const struct got_error *
2335 get_histedit_tmp_ref_name(char **refname, struct got_worktree *worktree)
2336 {
2337 	return get_ref_name(refname, worktree,
2338 	    GOT_WORKTREE_HISTEDIT_TMP_REF_PREFIX);
2339 }
2340 
2341 static const struct got_error *
2342 get_histedit_branch_symref_name(char **refname, struct got_worktree *worktree)
2343 {
2344 	return get_ref_name(refname, worktree,
2345 	    GOT_WORKTREE_HISTEDIT_BRANCH_REF_PREFIX);
2346 }
2347 
2348 static const struct got_error *
2349 get_histedit_base_commit_ref_name(char **refname, struct got_worktree *worktree)
2350 {
2351 	return get_ref_name(refname, worktree,
2352 	    GOT_WORKTREE_HISTEDIT_BASE_COMMIT_REF_PREFIX);
2353 }
2354 
2355 static const struct got_error *
2356 get_histedit_commit_ref_name(char **refname, struct got_worktree *worktree)
2357 {
2358 	return get_ref_name(refname, worktree,
2359 	    GOT_WORKTREE_HISTEDIT_COMMIT_REF_PREFIX);
2360 }
2361 
2362 const struct got_error *
2363 got_worktree_get_histedit_script_path(char **path,
2364     struct got_worktree *worktree)
2365 {
2366 	if (asprintf(path, "%s/%s/%s", worktree->root_path,
2367 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_HISTEDIT_SCRIPT) == -1) {
2368 		*path = NULL;
2369 		return got_error_from_errno("asprintf");
2370 	}
2371 	return NULL;
2372 }
2373 
2374 /*
2375  * Prevent Git's garbage collector from deleting our base commit by
2376  * setting a reference to our base commit's ID.
2377  */
2378 static const struct got_error *
2379 ref_base_commit(struct got_worktree *worktree, struct got_repository *repo)
2380 {
2381 	const struct got_error *err = NULL;
2382 	struct got_reference *ref = NULL;
2383 	char *refname;
2384 
2385 	err = got_worktree_get_base_ref_name(&refname, worktree);
2386 	if (err)
2387 		return err;
2388 
2389 	err = got_ref_alloc(&ref, refname, worktree->base_commit_id);
2390 	if (err)
2391 		goto done;
2392 
2393 	err = got_ref_write(ref, repo);
2394 done:
2395 	free(refname);
2396 	if (ref)
2397 		got_ref_close(ref);
2398 	return err;
2399 }
2400 
2401 static const struct got_error *
2402 get_fileindex_path(char **fileindex_path, struct got_worktree *worktree)
2403 {
2404 	const struct got_error *err = NULL;
2405 
2406 	if (asprintf(fileindex_path, "%s/%s/%s", worktree->root_path,
2407 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
2408 		err = got_error_from_errno("asprintf");
2409 		*fileindex_path = NULL;
2410 	}
2411 	return err;
2412 }
2413 
2414 
2415 static const struct got_error *
2416 open_fileindex(struct got_fileindex **fileindex, char **fileindex_path,
2417     struct got_worktree *worktree)
2418 {
2419 	const struct got_error *err = NULL;
2420 	FILE *index = NULL;
2421 
2422 	*fileindex_path = NULL;
2423 	*fileindex = got_fileindex_alloc();
2424 	if (*fileindex == NULL)
2425 		return got_error_from_errno("got_fileindex_alloc");
2426 
2427 	err = get_fileindex_path(fileindex_path, worktree);
2428 	if (err)
2429 		goto done;
2430 
2431 	index = fopen(*fileindex_path, "rb");
2432 	if (index == NULL) {
2433 		if (errno != ENOENT)
2434 			err = got_error_from_errno2("fopen", *fileindex_path);
2435 	} else {
2436 		err = got_fileindex_read(*fileindex, index);
2437 		if (fclose(index) == EOF && err == NULL)
2438 			err = got_error_from_errno("fclose");
2439 	}
2440 done:
2441 	if (err) {
2442 		free(*fileindex_path);
2443 		*fileindex_path = NULL;
2444 		got_fileindex_free(*fileindex);
2445 		*fileindex = NULL;
2446 	}
2447 	return err;
2448 }
2449 
2450 struct bump_base_commit_id_arg {
2451 	struct got_object_id *base_commit_id;
2452 	const char *path;
2453 	size_t path_len;
2454 	const char *entry_name;
2455 	got_worktree_checkout_cb progress_cb;
2456 	void *progress_arg;
2457 };
2458 
2459 /* Bump base commit ID of all files within an updated part of the work tree. */
2460 static const struct got_error *
2461 bump_base_commit_id(void *arg, struct got_fileindex_entry *ie)
2462 {
2463 	const struct got_error *err;
2464 	struct bump_base_commit_id_arg *a = arg;
2465 
2466 	if (a->entry_name) {
2467 		if (strcmp(ie->path, a->path) != 0)
2468 			return NULL;
2469 	} else if (!got_path_is_child(ie->path, a->path, a->path_len))
2470 		return NULL;
2471 
2472 	if (memcmp(ie->commit_sha1, a->base_commit_id->sha1,
2473 	    SHA1_DIGEST_LENGTH) == 0)
2474 		return NULL;
2475 
2476 	if (a->progress_cb) {
2477 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_BUMP_BASE,
2478 		    ie->path);
2479 		if (err)
2480 			return err;
2481 	}
2482 	memcpy(ie->commit_sha1, a->base_commit_id->sha1, SHA1_DIGEST_LENGTH);
2483 	return NULL;
2484 }
2485 
2486 static const struct got_error *
2487 bump_base_commit_id_everywhere(struct got_worktree *worktree,
2488      struct got_fileindex *fileindex,
2489      got_worktree_checkout_cb progress_cb, void *progress_arg)
2490 {
2491 	struct bump_base_commit_id_arg bbc_arg;
2492 
2493 	bbc_arg.base_commit_id = worktree->base_commit_id;
2494 	bbc_arg.entry_name = NULL;
2495 	bbc_arg.path = "";
2496 	bbc_arg.path_len = 0;
2497 	bbc_arg.progress_cb = progress_cb;
2498 	bbc_arg.progress_arg = progress_arg;
2499 
2500 	return got_fileindex_for_each_entry_safe(fileindex,
2501 	    bump_base_commit_id, &bbc_arg);
2502 }
2503 
2504 static const struct got_error *
2505 sync_fileindex(struct got_fileindex *fileindex, const char *fileindex_path)
2506 {
2507 	const struct got_error *err = NULL;
2508 	char *new_fileindex_path = NULL;
2509 	FILE *new_index = NULL;
2510 	struct timespec timeout;
2511 
2512 	err = got_opentemp_named(&new_fileindex_path, &new_index,
2513 	    fileindex_path);
2514 	if (err)
2515 		goto done;
2516 
2517 	err = got_fileindex_write(fileindex, new_index);
2518 	if (err)
2519 		goto done;
2520 
2521 	if (rename(new_fileindex_path, fileindex_path) != 0) {
2522 		err = got_error_from_errno3("rename", new_fileindex_path,
2523 		    fileindex_path);
2524 		unlink(new_fileindex_path);
2525 	}
2526 
2527 	/*
2528 	 * Sleep for a short amount of time to ensure that files modified after
2529 	 * this program exits have a different time stamp from the one which
2530 	 * was recorded in the file index.
2531 	 */
2532 	timeout.tv_sec = 0;
2533 	timeout.tv_nsec = 1;
2534 	nanosleep(&timeout,  NULL);
2535 done:
2536 	if (new_index)
2537 		fclose(new_index);
2538 	free(new_fileindex_path);
2539 	return err;
2540 }
2541 
2542 static const struct got_error *
2543 find_tree_entry_for_checkout(int *entry_type, char **tree_relpath,
2544     struct got_object_id **tree_id, const char *wt_relpath,
2545     struct got_worktree *worktree, struct got_repository *repo)
2546 {
2547 	const struct got_error *err = NULL;
2548 	struct got_object_id *id = NULL;
2549 	char *in_repo_path = NULL;
2550 	int is_root_wt = got_path_is_root_dir(worktree->path_prefix);
2551 
2552 	*entry_type = GOT_OBJ_TYPE_ANY;
2553 	*tree_relpath = NULL;
2554 	*tree_id = NULL;
2555 
2556 	if (wt_relpath[0] == '\0') {
2557 		/* Check out all files within the work tree. */
2558 		*entry_type = GOT_OBJ_TYPE_TREE;
2559 		*tree_relpath = strdup("");
2560 		if (*tree_relpath == NULL) {
2561 			err = got_error_from_errno("strdup");
2562 			goto done;
2563 		}
2564 		err = got_object_id_by_path(tree_id, repo,
2565 		    worktree->base_commit_id, worktree->path_prefix);
2566 		if (err)
2567 			goto done;
2568 		return NULL;
2569 	}
2570 
2571 	/* Check out a subset of files in the work tree. */
2572 
2573 	if (asprintf(&in_repo_path, "%s%s%s", worktree->path_prefix,
2574 	    is_root_wt ? "" : "/", wt_relpath) == -1) {
2575 		err = got_error_from_errno("asprintf");
2576 		goto done;
2577 	}
2578 
2579 	err = got_object_id_by_path(&id, repo, worktree->base_commit_id,
2580 	    in_repo_path);
2581 	if (err)
2582 		goto done;
2583 
2584 	free(in_repo_path);
2585 	in_repo_path = NULL;
2586 
2587 	err = got_object_get_type(entry_type, repo, id);
2588 	if (err)
2589 		goto done;
2590 
2591 	if (*entry_type == GOT_OBJ_TYPE_BLOB) {
2592 		/* Check out a single file. */
2593 		if (strchr(wt_relpath, '/')  == NULL) {
2594 			/* Check out a single file in work tree's root dir. */
2595 			in_repo_path = strdup(worktree->path_prefix);
2596 			if (in_repo_path == NULL) {
2597 				err = got_error_from_errno("strdup");
2598 				goto done;
2599 			}
2600 			*tree_relpath = strdup("");
2601 			if (*tree_relpath == NULL) {
2602 				err = got_error_from_errno("strdup");
2603 				goto done;
2604 			}
2605 		} else {
2606 			/* Check out a single file in a subdirectory. */
2607 			err = got_path_dirname(tree_relpath, wt_relpath);
2608 			if (err)
2609 				return err;
2610 			if (asprintf(&in_repo_path, "%s%s%s",
2611 			    worktree->path_prefix, is_root_wt ? "" : "/",
2612 			    *tree_relpath) == -1) {
2613 				err = got_error_from_errno("asprintf");
2614 				goto done;
2615 			}
2616 		}
2617 		err = got_object_id_by_path(tree_id, repo,
2618 		    worktree->base_commit_id, in_repo_path);
2619 	} else {
2620 		/* Check out all files within a subdirectory. */
2621 		*tree_id = got_object_id_dup(id);
2622 		if (*tree_id == NULL) {
2623 			err = got_error_from_errno("got_object_id_dup");
2624 			goto done;
2625 		}
2626 		*tree_relpath = strdup(wt_relpath);
2627 		if (*tree_relpath == NULL) {
2628 			err = got_error_from_errno("strdup");
2629 			goto done;
2630 		}
2631 	}
2632 done:
2633 	free(id);
2634 	free(in_repo_path);
2635 	if (err) {
2636 		*entry_type = GOT_OBJ_TYPE_ANY;
2637 		free(*tree_relpath);
2638 		*tree_relpath = NULL;
2639 		free(*tree_id);
2640 		*tree_id = NULL;
2641 	}
2642 	return err;
2643 }
2644 
2645 static const struct got_error *
2646 checkout_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
2647     const char *relpath, struct got_object_id *tree_id, const char *entry_name,
2648     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
2649     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
2650 {
2651 	const struct got_error *err = NULL;
2652 	struct got_commit_object *commit = NULL;
2653 	struct got_tree_object *tree = NULL;
2654 	struct got_fileindex_diff_tree_cb diff_cb;
2655 	struct diff_cb_arg arg;
2656 
2657 	err = ref_base_commit(worktree, repo);
2658 	if (err) {
2659 		if (!(err->code == GOT_ERR_ERRNO &&
2660 		    (errno == EACCES || errno == EROFS)))
2661 			goto done;
2662 		err = (*progress_cb)(progress_arg,
2663 		    GOT_STATUS_BASE_REF_ERR, worktree->root_path);
2664 		if (err)
2665 			return err;
2666 	}
2667 
2668 	err = got_object_open_as_commit(&commit, repo,
2669 	    worktree->base_commit_id);
2670 	if (err)
2671 		goto done;
2672 
2673 	err = got_object_open_as_tree(&tree, repo, tree_id);
2674 	if (err)
2675 		goto done;
2676 
2677 	if (entry_name &&
2678 	    got_object_tree_find_entry(tree, entry_name) == NULL) {
2679 		err = got_error_path(entry_name, GOT_ERR_NO_TREE_ENTRY);
2680 		goto done;
2681 	}
2682 
2683 	diff_cb.diff_old_new = diff_old_new;
2684 	diff_cb.diff_old = diff_old;
2685 	diff_cb.diff_new = diff_new;
2686 	arg.fileindex = fileindex;
2687 	arg.worktree = worktree;
2688 	arg.repo = repo;
2689 	arg.progress_cb = progress_cb;
2690 	arg.progress_arg = progress_arg;
2691 	arg.cancel_cb = cancel_cb;
2692 	arg.cancel_arg = cancel_arg;
2693 	err = got_fileindex_diff_tree(fileindex, tree, relpath,
2694 	    entry_name, repo, &diff_cb, &arg);
2695 done:
2696 	if (tree)
2697 		got_object_tree_close(tree);
2698 	if (commit)
2699 		got_object_commit_close(commit);
2700 	return err;
2701 }
2702 
2703 const struct got_error *
2704 got_worktree_checkout_files(struct got_worktree *worktree,
2705     struct got_pathlist_head *paths, struct got_repository *repo,
2706     got_worktree_checkout_cb progress_cb, void *progress_arg,
2707     got_cancel_cb cancel_cb, void *cancel_arg)
2708 {
2709 	const struct got_error *err = NULL, *sync_err, *unlockerr;
2710 	struct got_commit_object *commit = NULL;
2711 	struct got_tree_object *tree = NULL;
2712 	struct got_fileindex *fileindex = NULL;
2713 	char *fileindex_path = NULL;
2714 	struct got_pathlist_entry *pe;
2715 	struct tree_path_data {
2716 		SIMPLEQ_ENTRY(tree_path_data) entry;
2717 		struct got_object_id *tree_id;
2718 		int entry_type;
2719 		char *relpath;
2720 		char *entry_name;
2721 	} *tpd = NULL;
2722 	SIMPLEQ_HEAD(tree_paths, tree_path_data) tree_paths;
2723 
2724 	SIMPLEQ_INIT(&tree_paths);
2725 
2726 	err = lock_worktree(worktree, LOCK_EX);
2727 	if (err)
2728 		return err;
2729 
2730 	/* Map all specified paths to in-repository trees. */
2731 	TAILQ_FOREACH(pe, paths, entry) {
2732 		tpd = malloc(sizeof(*tpd));
2733 		if (tpd == NULL) {
2734 			err = got_error_from_errno("malloc");
2735 			goto done;
2736 		}
2737 
2738 		err = find_tree_entry_for_checkout(&tpd->entry_type,
2739 		    &tpd->relpath, &tpd->tree_id, pe->path, worktree, repo);
2740 		if (err) {
2741 			free(tpd);
2742 			goto done;
2743 		}
2744 
2745 		if (tpd->entry_type == GOT_OBJ_TYPE_BLOB) {
2746 			err = got_path_basename(&tpd->entry_name, pe->path);
2747 			if (err) {
2748 				free(tpd->relpath);
2749 				free(tpd->tree_id);
2750 				free(tpd);
2751 				goto done;
2752 			}
2753 		} else
2754 			tpd->entry_name = NULL;
2755 
2756 		SIMPLEQ_INSERT_TAIL(&tree_paths, tpd, entry);
2757 	}
2758 
2759 	/*
2760 	 * Read the file index.
2761 	 * Checking out files is supposed to be an idempotent operation.
2762 	 * If the on-disk file index is incomplete we will try to complete it.
2763 	 */
2764 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
2765 	if (err)
2766 		goto done;
2767 
2768 	tpd = SIMPLEQ_FIRST(&tree_paths);
2769 	TAILQ_FOREACH(pe, paths, entry) {
2770 		struct bump_base_commit_id_arg bbc_arg;
2771 
2772 		err = checkout_files(worktree, fileindex, tpd->relpath,
2773 		    tpd->tree_id, tpd->entry_name, repo,
2774 		    progress_cb, progress_arg, cancel_cb, cancel_arg);
2775 		if (err)
2776 			break;
2777 
2778 		bbc_arg.base_commit_id = worktree->base_commit_id;
2779 		bbc_arg.entry_name = tpd->entry_name;
2780 		bbc_arg.path = pe->path;
2781 		bbc_arg.path_len = pe->path_len;
2782 		bbc_arg.progress_cb = progress_cb;
2783 		bbc_arg.progress_arg = progress_arg;
2784 		err = got_fileindex_for_each_entry_safe(fileindex,
2785 		    bump_base_commit_id, &bbc_arg);
2786 		if (err)
2787 			break;
2788 
2789 		tpd = SIMPLEQ_NEXT(tpd, entry);
2790 	}
2791 	sync_err = sync_fileindex(fileindex, fileindex_path);
2792 	if (sync_err && err == NULL)
2793 		err = sync_err;
2794 done:
2795 	free(fileindex_path);
2796 	if (tree)
2797 		got_object_tree_close(tree);
2798 	if (commit)
2799 		got_object_commit_close(commit);
2800 	if (fileindex)
2801 		got_fileindex_free(fileindex);
2802 	while (!SIMPLEQ_EMPTY(&tree_paths)) {
2803 		tpd = SIMPLEQ_FIRST(&tree_paths);
2804 		SIMPLEQ_REMOVE_HEAD(&tree_paths, entry);
2805 		free(tpd->relpath);
2806 		free(tpd->tree_id);
2807 		free(tpd);
2808 	}
2809 	unlockerr = lock_worktree(worktree, LOCK_SH);
2810 	if (unlockerr && err == NULL)
2811 		err = unlockerr;
2812 	return err;
2813 }
2814 
2815 struct merge_file_cb_arg {
2816     struct got_worktree *worktree;
2817     struct got_fileindex *fileindex;
2818     got_worktree_checkout_cb progress_cb;
2819     void *progress_arg;
2820     got_cancel_cb cancel_cb;
2821     void *cancel_arg;
2822     const char *label_orig;
2823     struct got_object_id *commit_id2;
2824 };
2825 
2826 static const struct got_error *
2827 merge_file_cb(void *arg, struct got_blob_object *blob1,
2828     struct got_blob_object *blob2, struct got_object_id *id1,
2829     struct got_object_id *id2, const char *path1, const char *path2,
2830     mode_t mode1, mode_t mode2, struct got_repository *repo)
2831 {
2832 	static const struct got_error *err = NULL;
2833 	struct merge_file_cb_arg *a = arg;
2834 	struct got_fileindex_entry *ie;
2835 	char *ondisk_path = NULL;
2836 	struct stat sb;
2837 	unsigned char status;
2838 	int local_changes_subsumed;
2839 	FILE *f_orig = NULL, *f_deriv = NULL, *f_deriv2 = NULL;
2840 	char *id_str = NULL, *label_deriv2 = NULL;
2841 
2842 	if (blob1 && blob2) {
2843 		ie = got_fileindex_entry_get(a->fileindex, path2,
2844 		    strlen(path2));
2845 		if (ie == NULL)
2846 			return (*a->progress_cb)(a->progress_arg,
2847 			    GOT_STATUS_MISSING, path2);
2848 
2849 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2850 		    path2) == -1)
2851 			return got_error_from_errno("asprintf");
2852 
2853 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2854 		    repo);
2855 		if (err)
2856 			goto done;
2857 
2858 		if (status == GOT_STATUS_DELETE) {
2859 			err = (*a->progress_cb)(a->progress_arg,
2860 			    GOT_STATUS_MERGE, path2);
2861 			goto done;
2862 		}
2863 		if (status != GOT_STATUS_NO_CHANGE &&
2864 		    status != GOT_STATUS_MODIFY &&
2865 		    status != GOT_STATUS_CONFLICT &&
2866 		    status != GOT_STATUS_ADD) {
2867 			err = (*a->progress_cb)(a->progress_arg, status, path2);
2868 			goto done;
2869 		}
2870 
2871 		if (S_ISLNK(mode1) && S_ISLNK(mode2)) {
2872 			char *link_target2;
2873 			err = got_object_blob_read_to_str(&link_target2, blob2);
2874 			if (err)
2875 				goto done;
2876 			err = merge_symlink(a->worktree, blob1, ondisk_path,
2877 			    path2, a->label_orig, link_target2, a->commit_id2,
2878 			    repo, a->progress_cb, a->progress_arg);
2879 			free(link_target2);
2880 		} else {
2881 			int fd;
2882 
2883 			f_orig = got_opentemp();
2884 			if (f_orig == NULL) {
2885 				err = got_error_from_errno("got_opentemp");
2886 				goto done;
2887 			}
2888 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2889 			    f_orig, blob1);
2890 			if (err)
2891 				goto done;
2892 
2893 			f_deriv2 = got_opentemp();
2894 			if (f_deriv2 == NULL)
2895 				goto done;
2896 			err = got_object_blob_dump_to_file(NULL, NULL, NULL,
2897 			    f_deriv2, blob2);
2898 			if (err)
2899 				goto done;
2900 
2901 			fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW);
2902 			if (fd == -1) {
2903 				err = got_error_from_errno2("open",
2904 				    ondisk_path);
2905 				goto done;
2906 			}
2907 			f_deriv = fdopen(fd, "r");
2908 			if (f_deriv == NULL) {
2909 				err = got_error_from_errno2("fdopen",
2910 				    ondisk_path);
2911 				close(fd);
2912 				goto done;
2913 			}
2914 			err = got_object_id_str(&id_str, a->commit_id2);
2915 			if (err)
2916 				goto done;
2917 			if (asprintf(&label_deriv2, "%s: commit %s",
2918 			    GOT_MERGE_LABEL_MERGED, id_str) == -1) {
2919 				err = got_error_from_errno("asprintf");
2920 				goto done;
2921 			}
2922 			err = merge_file(&local_changes_subsumed, a->worktree,
2923 			    f_orig, f_deriv, f_deriv2, ondisk_path, path2,
2924 			    sb.st_mode, a->label_orig, NULL, label_deriv2,
2925 			    GOT_DIFF_ALGORITHM_PATIENCE, repo,
2926 			    a->progress_cb, a->progress_arg);
2927 		}
2928 	} else if (blob1) {
2929 		ie = got_fileindex_entry_get(a->fileindex, path1,
2930 		    strlen(path1));
2931 		if (ie == NULL)
2932 			return (*a->progress_cb)(a->progress_arg,
2933 			    GOT_STATUS_MISSING, path1);
2934 
2935 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
2936 		    path1) == -1)
2937 			return got_error_from_errno("asprintf");
2938 
2939 		err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL,
2940 		    repo);
2941 		if (err)
2942 			goto done;
2943 
2944 		switch (status) {
2945 		case GOT_STATUS_NO_CHANGE:
2946 			err = (*a->progress_cb)(a->progress_arg,
2947 			    GOT_STATUS_DELETE, path1);
2948 			if (err)
2949 				goto done;
2950 			err = remove_ondisk_file(a->worktree->root_path, path1);
2951 			if (err)
2952 				goto done;
2953 			if (ie)
2954 				got_fileindex_entry_mark_deleted_from_disk(ie);
2955 			break;
2956 		case GOT_STATUS_DELETE:
2957 		case GOT_STATUS_MISSING:
2958 			err = (*a->progress_cb)(a->progress_arg,
2959 			    GOT_STATUS_DELETE, path1);
2960 			if (err)
2961 				goto done;
2962 			if (ie)
2963 				got_fileindex_entry_mark_deleted_from_disk(ie);
2964 			break;
2965 		case GOT_STATUS_ADD: {
2966 			struct got_object_id *id;
2967 			FILE *blob1_f;
2968 			/*
2969 			 * Delete the added file only if its content already
2970 			 * exists in the repository.
2971 			 */
2972 			err = got_object_blob_file_create(&id, &blob1_f, path1);
2973 			if (err)
2974 				goto done;
2975 			if (got_object_id_cmp(id, id1) == 0) {
2976 				err = (*a->progress_cb)(a->progress_arg,
2977 				    GOT_STATUS_DELETE, path1);
2978 				if (err)
2979 					goto done;
2980 				err = remove_ondisk_file(a->worktree->root_path,
2981 				    path1);
2982 				if (err)
2983 					goto done;
2984 				if (ie)
2985 					got_fileindex_entry_remove(a->fileindex,
2986 					    ie);
2987 			} else {
2988 				err = (*a->progress_cb)(a->progress_arg,
2989 				    GOT_STATUS_CANNOT_DELETE, path1);
2990 			}
2991 			if (fclose(blob1_f) == EOF && err == NULL)
2992 				err = got_error_from_errno("fclose");
2993 			free(id);
2994 			if (err)
2995 				goto done;
2996 			break;
2997 		}
2998 		case GOT_STATUS_MODIFY:
2999 		case GOT_STATUS_CONFLICT:
3000 			err = (*a->progress_cb)(a->progress_arg,
3001 			    GOT_STATUS_CANNOT_DELETE, path1);
3002 			if (err)
3003 				goto done;
3004 			break;
3005 		case GOT_STATUS_OBSTRUCTED:
3006 			err = (*a->progress_cb)(a->progress_arg, status, path1);
3007 			if (err)
3008 				goto done;
3009 			break;
3010 		default:
3011 			break;
3012 		}
3013 	} else if (blob2) {
3014 		if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
3015 		    path2) == -1)
3016 			return got_error_from_errno("asprintf");
3017 		ie = got_fileindex_entry_get(a->fileindex, path2,
3018 		    strlen(path2));
3019 		if (ie) {
3020 			err = get_file_status(&status, &sb, ie, ondisk_path,
3021 			    -1, NULL, repo);
3022 			if (err)
3023 				goto done;
3024 			if (status != GOT_STATUS_NO_CHANGE &&
3025 			    status != GOT_STATUS_MODIFY &&
3026 			    status != GOT_STATUS_CONFLICT &&
3027 			    status != GOT_STATUS_ADD) {
3028 				err = (*a->progress_cb)(a->progress_arg,
3029 				    status, path2);
3030 				goto done;
3031 			}
3032 			if (S_ISLNK(mode2) && S_ISLNK(sb.st_mode)) {
3033 				char *link_target2;
3034 				err = got_object_blob_read_to_str(&link_target2,
3035 				    blob2);
3036 				if (err)
3037 					goto done;
3038 				err = merge_symlink(a->worktree, NULL,
3039 				    ondisk_path, path2, a->label_orig,
3040 				    link_target2, a->commit_id2, repo,
3041 				    a->progress_cb, a->progress_arg);
3042 				free(link_target2);
3043 			} else if (S_ISREG(sb.st_mode)) {
3044 				err = merge_blob(&local_changes_subsumed,
3045 				    a->worktree, NULL, ondisk_path, path2,
3046 				    sb.st_mode, a->label_orig, blob2,
3047 				    a->commit_id2, repo, a->progress_cb,
3048 				    a->progress_arg);
3049 			} else {
3050 				err = got_error_path(ondisk_path,
3051 				    GOT_ERR_FILE_OBSTRUCTED);
3052 			}
3053 			if (err)
3054 				goto done;
3055 			if (status == GOT_STATUS_DELETE) {
3056 				err = got_fileindex_entry_update(ie,
3057 				    a->worktree->root_fd, path2, blob2->id.sha1,
3058 				    a->worktree->base_commit_id->sha1, 0);
3059 				if (err)
3060 					goto done;
3061 			}
3062 		} else {
3063 			int is_bad_symlink = 0;
3064 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
3065 			if (S_ISLNK(mode2)) {
3066 				err = install_symlink(&is_bad_symlink,
3067 				    a->worktree, ondisk_path, path2, blob2, 0,
3068 				    0, 1, repo, a->progress_cb, a->progress_arg);
3069 			} else {
3070 				err = install_blob(a->worktree, ondisk_path, path2,
3071 				    mode2, sb.st_mode, blob2, 0, 0, 0, 1, repo,
3072 				    a->progress_cb, a->progress_arg);
3073 			}
3074 			if (err)
3075 				goto done;
3076 			err = got_fileindex_entry_alloc(&ie, path2);
3077 			if (err)
3078 				goto done;
3079 			err = got_fileindex_entry_update(ie,
3080 			    a->worktree->root_fd, path2, NULL, NULL, 1);
3081 			if (err) {
3082 				got_fileindex_entry_free(ie);
3083 				goto done;
3084 			}
3085 			err = got_fileindex_entry_add(a->fileindex, ie);
3086 			if (err) {
3087 				got_fileindex_entry_free(ie);
3088 				goto done;
3089 			}
3090 			if (is_bad_symlink) {
3091 				got_fileindex_entry_filetype_set(ie,
3092 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
3093 			}
3094 		}
3095 	}
3096 done:
3097 	if (f_orig && fclose(f_orig) == EOF && err == NULL)
3098 		err = got_error_from_errno("fclose");
3099 	if (f_deriv && fclose(f_deriv) == EOF && err == NULL)
3100 		err = got_error_from_errno("fclose");
3101 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
3102 		err = got_error_from_errno("fclose");
3103 	free(id_str);
3104 	free(label_deriv2);
3105 	free(ondisk_path);
3106 	return err;
3107 }
3108 
3109 struct check_merge_ok_arg {
3110 	struct got_worktree *worktree;
3111 	struct got_repository *repo;
3112 };
3113 
3114 static const struct got_error *
3115 check_merge_ok(void *arg, struct got_fileindex_entry *ie)
3116 {
3117 	const struct got_error *err = NULL;
3118 	struct check_merge_ok_arg *a = arg;
3119 	unsigned char status;
3120 	struct stat sb;
3121 	char *ondisk_path;
3122 
3123 	/* Reject merges into a work tree with mixed base commits. */
3124 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
3125 	    SHA1_DIGEST_LENGTH))
3126 		return got_error(GOT_ERR_MIXED_COMMITS);
3127 
3128 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
3129 	    == -1)
3130 		return got_error_from_errno("asprintf");
3131 
3132 	/* Reject merges into a work tree with conflicted files. */
3133 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
3134 	if (err)
3135 		return err;
3136 	if (status == GOT_STATUS_CONFLICT)
3137 		return got_error(GOT_ERR_CONFLICTS);
3138 
3139 	return NULL;
3140 }
3141 
3142 static const struct got_error *
3143 merge_files(struct got_worktree *worktree, struct got_fileindex *fileindex,
3144     const char *fileindex_path, struct got_object_id *commit_id1,
3145     struct got_object_id *commit_id2, struct got_repository *repo,
3146     got_worktree_checkout_cb progress_cb, void *progress_arg,
3147     got_cancel_cb cancel_cb, void *cancel_arg)
3148 {
3149 	const struct got_error *err = NULL, *sync_err;
3150 	struct got_object_id *tree_id1 = NULL, *tree_id2 = NULL;
3151 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
3152 	struct merge_file_cb_arg arg;
3153 	char *label_orig = NULL;
3154 
3155 	if (commit_id1) {
3156 		err = got_object_id_by_path(&tree_id1, repo, commit_id1,
3157 		    worktree->path_prefix);
3158 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
3159 			goto done;
3160 	}
3161 	if (tree_id1) {
3162 		char *id_str;
3163 
3164 		err = got_object_open_as_tree(&tree1, repo, tree_id1);
3165 		if (err)
3166 			goto done;
3167 
3168 		err = got_object_id_str(&id_str, commit_id1);
3169 		if (err)
3170 			goto done;
3171 
3172 		if (asprintf(&label_orig, "%s: commit %s",
3173 		    GOT_MERGE_LABEL_BASE, id_str) == -1) {
3174 			err = got_error_from_errno("asprintf");
3175 			free(id_str);
3176 			goto done;
3177 		}
3178 		free(id_str);
3179 	}
3180 
3181 	err = got_object_id_by_path(&tree_id2, repo, commit_id2,
3182 	    worktree->path_prefix);
3183 	if (err)
3184 		goto done;
3185 
3186 	err = got_object_open_as_tree(&tree2, repo, tree_id2);
3187 	if (err)
3188 		goto done;
3189 
3190 	arg.worktree = worktree;
3191 	arg.fileindex = fileindex;
3192 	arg.progress_cb = progress_cb;
3193 	arg.progress_arg = progress_arg;
3194 	arg.cancel_cb = cancel_cb;
3195 	arg.cancel_arg = cancel_arg;
3196 	arg.label_orig = label_orig;
3197 	arg.commit_id2 = commit_id2;
3198 	err = got_diff_tree(tree1, tree2, "", "", repo, merge_file_cb, &arg, 1);
3199 	sync_err = sync_fileindex(fileindex, fileindex_path);
3200 	if (sync_err && err == NULL)
3201 		err = sync_err;
3202 done:
3203 	if (tree1)
3204 		got_object_tree_close(tree1);
3205 	if (tree2)
3206 		got_object_tree_close(tree2);
3207 	free(label_orig);
3208 	return err;
3209 }
3210 
3211 const struct got_error *
3212 got_worktree_merge_files(struct got_worktree *worktree,
3213     struct got_object_id *commit_id1, struct got_object_id *commit_id2,
3214     struct got_repository *repo, got_worktree_checkout_cb progress_cb,
3215     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
3216 {
3217 	const struct got_error *err, *unlockerr;
3218 	char *fileindex_path = NULL;
3219 	struct got_fileindex *fileindex = NULL;
3220 	struct check_merge_ok_arg mok_arg;
3221 
3222 	err = lock_worktree(worktree, LOCK_EX);
3223 	if (err)
3224 		return err;
3225 
3226 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3227 	if (err)
3228 		goto done;
3229 
3230 	mok_arg.worktree = worktree;
3231 	mok_arg.repo = repo;
3232 	err = got_fileindex_for_each_entry_safe(fileindex, check_merge_ok,
3233 	    &mok_arg);
3234 	if (err)
3235 		goto done;
3236 
3237 	err = merge_files(worktree, fileindex, fileindex_path, commit_id1,
3238 	    commit_id2, repo, progress_cb, progress_arg, cancel_cb, cancel_arg);
3239 done:
3240 	if (fileindex)
3241 		got_fileindex_free(fileindex);
3242 	free(fileindex_path);
3243 	unlockerr = lock_worktree(worktree, LOCK_SH);
3244 	if (unlockerr && err == NULL)
3245 		err = unlockerr;
3246 	return err;
3247 }
3248 
3249 struct diff_dir_cb_arg {
3250     struct got_fileindex *fileindex;
3251     struct got_worktree *worktree;
3252     const char *status_path;
3253     size_t status_path_len;
3254     struct got_repository *repo;
3255     got_worktree_status_cb status_cb;
3256     void *status_arg;
3257     got_cancel_cb cancel_cb;
3258     void *cancel_arg;
3259     /* A pathlist containing per-directory pathlists of ignore patterns. */
3260     struct got_pathlist_head ignores;
3261     int report_unchanged;
3262     int no_ignores;
3263 };
3264 
3265 static const struct got_error *
3266 report_file_status(struct got_fileindex_entry *ie, const char *abspath,
3267     int dirfd, const char *de_name,
3268     got_worktree_status_cb status_cb, void *status_arg,
3269     struct got_repository *repo, int report_unchanged)
3270 {
3271 	const struct got_error *err = NULL;
3272 	unsigned char status = GOT_STATUS_NO_CHANGE;
3273 	unsigned char staged_status = get_staged_status(ie);
3274 	struct stat sb;
3275 	struct got_object_id blob_id, commit_id, staged_blob_id;
3276 	struct got_object_id *blob_idp = NULL, *commit_idp = NULL;
3277 	struct got_object_id *staged_blob_idp = NULL;
3278 
3279 	err = get_file_status(&status, &sb, ie, abspath, dirfd, de_name, repo);
3280 	if (err)
3281 		return err;
3282 
3283 	if (status == GOT_STATUS_NO_CHANGE &&
3284 	    staged_status == GOT_STATUS_NO_CHANGE && !report_unchanged)
3285 		return NULL;
3286 
3287 	if (got_fileindex_entry_has_blob(ie)) {
3288 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
3289 		blob_idp = &blob_id;
3290 	}
3291 	if (got_fileindex_entry_has_commit(ie)) {
3292 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
3293 		commit_idp = &commit_id;
3294 	}
3295 	if (staged_status == GOT_STATUS_ADD ||
3296 	    staged_status == GOT_STATUS_MODIFY) {
3297 		memcpy(staged_blob_id.sha1, ie->staged_blob_sha1,
3298 		    SHA1_DIGEST_LENGTH);
3299 		staged_blob_idp = &staged_blob_id;
3300 	}
3301 
3302 	return (*status_cb)(status_arg, status, staged_status,
3303 	    ie->path, blob_idp, staged_blob_idp, commit_idp, dirfd, de_name);
3304 }
3305 
3306 static const struct got_error *
3307 status_old_new(void *arg, struct got_fileindex_entry *ie,
3308     struct dirent *de, const char *parent_path, int dirfd)
3309 {
3310 	const struct got_error *err = NULL;
3311 	struct diff_dir_cb_arg *a = arg;
3312 	char *abspath;
3313 
3314 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3315 		return got_error(GOT_ERR_CANCELLED);
3316 
3317 	if (got_path_cmp(parent_path, a->status_path,
3318 	    strlen(parent_path), a->status_path_len) != 0 &&
3319 	    !got_path_is_child(parent_path, a->status_path, a->status_path_len))
3320 		return NULL;
3321 
3322 	if (parent_path[0]) {
3323 		if (asprintf(&abspath, "%s/%s/%s", a->worktree->root_path,
3324 		    parent_path, de->d_name) == -1)
3325 			return got_error_from_errno("asprintf");
3326 	} else {
3327 		if (asprintf(&abspath, "%s/%s", a->worktree->root_path,
3328 		    de->d_name) == -1)
3329 			return got_error_from_errno("asprintf");
3330 	}
3331 
3332 	err = report_file_status(ie, abspath, dirfd, de->d_name,
3333 	    a->status_cb, a->status_arg, a->repo, a->report_unchanged);
3334 	free(abspath);
3335 	return err;
3336 }
3337 
3338 static const struct got_error *
3339 status_old(void *arg, struct got_fileindex_entry *ie, const char *parent_path)
3340 {
3341 	struct diff_dir_cb_arg *a = arg;
3342 	struct got_object_id blob_id, commit_id;
3343 	unsigned char status;
3344 
3345 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3346 		return got_error(GOT_ERR_CANCELLED);
3347 
3348 	if (!got_path_is_child(ie->path, a->status_path, a->status_path_len))
3349 		return NULL;
3350 
3351 	memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
3352 	memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
3353 	if (got_fileindex_entry_has_file_on_disk(ie))
3354 		status = GOT_STATUS_MISSING;
3355 	else
3356 		status = GOT_STATUS_DELETE;
3357 	return (*a->status_cb)(a->status_arg, status, get_staged_status(ie),
3358 	    ie->path, &blob_id, NULL, &commit_id, -1, NULL);
3359 }
3360 
3361 void
3362 free_ignorelist(struct got_pathlist_head *ignorelist)
3363 {
3364 	struct got_pathlist_entry *pe;
3365 
3366 	TAILQ_FOREACH(pe, ignorelist, entry)
3367 		free((char *)pe->path);
3368 	got_pathlist_free(ignorelist);
3369 }
3370 
3371 void
3372 free_ignores(struct got_pathlist_head *ignores)
3373 {
3374 	struct got_pathlist_entry *pe;
3375 
3376 	TAILQ_FOREACH(pe, ignores, entry) {
3377 		struct got_pathlist_head *ignorelist = pe->data;
3378 		free_ignorelist(ignorelist);
3379 		free((char *)pe->path);
3380 	}
3381 	got_pathlist_free(ignores);
3382 }
3383 
3384 static const struct got_error *
3385 read_ignores(struct got_pathlist_head *ignores, const char *path, FILE *f)
3386 {
3387 	const struct got_error *err = NULL;
3388 	struct got_pathlist_entry *pe = NULL;
3389 	struct got_pathlist_head *ignorelist;
3390 	char *line = NULL, *pattern, *dirpath = NULL;
3391 	size_t linesize = 0;
3392 	ssize_t linelen;
3393 
3394 	ignorelist = calloc(1, sizeof(*ignorelist));
3395 	if (ignorelist == NULL)
3396 		return got_error_from_errno("calloc");
3397 	TAILQ_INIT(ignorelist);
3398 
3399 	while ((linelen = getline(&line, &linesize, f)) != -1) {
3400 		if (linelen > 0 && line[linelen - 1] == '\n')
3401 			line[linelen - 1] = '\0';
3402 
3403 		/* Git's ignores may contain comments. */
3404 		if (line[0] == '#')
3405 			continue;
3406 
3407 		/* Git's negated patterns are not (yet?) supported. */
3408 		if (line[0] == '!')
3409 			continue;
3410 
3411 		if (asprintf(&pattern, "%s%s%s", path, path[0] ? "/" : "",
3412 		    line) == -1) {
3413 			err = got_error_from_errno("asprintf");
3414 			goto done;
3415 		}
3416 		err = got_pathlist_insert(NULL, ignorelist, pattern, NULL);
3417 		if (err)
3418 			goto done;
3419 	}
3420 	if (ferror(f)) {
3421 		err = got_error_from_errno("getline");
3422 		goto done;
3423 	}
3424 
3425 	dirpath = strdup(path);
3426 	if (dirpath == NULL) {
3427 		err = got_error_from_errno("strdup");
3428 		goto done;
3429 	}
3430 	err = got_pathlist_insert(&pe, ignores, dirpath, ignorelist);
3431 done:
3432 	free(line);
3433 	if (err || pe == NULL) {
3434 		free(dirpath);
3435 		free_ignorelist(ignorelist);
3436 	}
3437 	return err;
3438 }
3439 
3440 int
3441 match_ignores(struct got_pathlist_head *ignores, const char *path)
3442 {
3443 	struct got_pathlist_entry *pe;
3444 
3445 	/* Handle patterns which match in all directories. */
3446 	TAILQ_FOREACH(pe, ignores, entry) {
3447 		struct got_pathlist_head *ignorelist = pe->data;
3448 		struct got_pathlist_entry *pi;
3449 
3450 		TAILQ_FOREACH(pi, ignorelist, entry) {
3451 			const char *p, *pattern = pi->path;
3452 
3453 			if (strncmp(pattern, "**/", 3) != 0)
3454 				continue;
3455 			pattern += 3;
3456 			p = path;
3457 			while (*p) {
3458 				if (fnmatch(pattern, p,
3459 				    FNM_PATHNAME | FNM_LEADING_DIR)) {
3460 					/* Retry in next directory. */
3461 					while (*p && *p != '/')
3462 						p++;
3463 					while (*p == '/')
3464 						p++;
3465 					continue;
3466 				}
3467 				return 1;
3468 			}
3469 		}
3470 	}
3471 
3472 	/*
3473 	 * The ignores pathlist contains ignore lists from children before
3474 	 * parents, so we can find the most specific ignorelist by walking
3475 	 * ignores backwards.
3476 	 */
3477 	pe = TAILQ_LAST(ignores, got_pathlist_head);
3478 	while (pe) {
3479 		if (got_path_is_child(path, pe->path, pe->path_len)) {
3480 			struct got_pathlist_head *ignorelist = pe->data;
3481 			struct got_pathlist_entry *pi;
3482 			TAILQ_FOREACH(pi, ignorelist, entry) {
3483 				const char *pattern = pi->path;
3484 				int flags = FNM_LEADING_DIR;
3485 				if (strstr(pattern, "/**/") == NULL)
3486 					flags |= FNM_PATHNAME;
3487 				if (fnmatch(pattern, path, flags))
3488 					continue;
3489 				return 1;
3490 			}
3491 		}
3492 		pe = TAILQ_PREV(pe, got_pathlist_head, entry);
3493 	}
3494 
3495 	return 0;
3496 }
3497 
3498 static const struct got_error *
3499 add_ignores(struct got_pathlist_head *ignores, const char *root_path,
3500     const char *path, int dirfd, const char *ignores_filename)
3501 {
3502 	const struct got_error *err = NULL;
3503 	char *ignorespath;
3504 	int fd = -1;
3505 	FILE *ignoresfile = NULL;
3506 
3507 	if (asprintf(&ignorespath, "%s/%s%s%s", root_path, path,
3508 	    path[0] ? "/" : "", ignores_filename) == -1)
3509 		return got_error_from_errno("asprintf");
3510 
3511 	if (dirfd != -1) {
3512 		fd = openat(dirfd, ignores_filename, O_RDONLY | O_NOFOLLOW);
3513 		if (fd == -1) {
3514 			if (errno != ENOENT && errno != EACCES)
3515 				err = got_error_from_errno2("openat",
3516 				    ignorespath);
3517 		} else {
3518 			ignoresfile = fdopen(fd, "r");
3519 			if (ignoresfile == NULL) 
3520 				err = got_error_from_errno2("fdopen",
3521 				    ignorespath);
3522 			else {
3523 				fd = -1;
3524 				err = read_ignores(ignores, path, ignoresfile);
3525 			}
3526 		}
3527 	} else {
3528 		ignoresfile = fopen(ignorespath, "r");
3529 		if (ignoresfile == NULL) {
3530 			if (errno != ENOENT && errno != EACCES)
3531 				err = got_error_from_errno2("fopen",
3532 				    ignorespath);
3533 		} else
3534 			err = read_ignores(ignores, path, ignoresfile);
3535 	}
3536 
3537 	if (ignoresfile && fclose(ignoresfile) == EOF && err == NULL)
3538 		err = got_error_from_errno2("fclose", path);
3539 	if (fd != -1 && close(fd) == -1 && err == NULL)
3540 		err = got_error_from_errno2("close", path);
3541 	free(ignorespath);
3542 	return err;
3543 }
3544 
3545 static const struct got_error *
3546 status_new(void *arg, struct dirent *de, const char *parent_path, int dirfd)
3547 {
3548 	const struct got_error *err = NULL;
3549 	struct diff_dir_cb_arg *a = arg;
3550 	char *path = NULL;
3551 
3552 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
3553 		return got_error(GOT_ERR_CANCELLED);
3554 
3555 	if (parent_path[0]) {
3556 		if (asprintf(&path, "%s/%s", parent_path, de->d_name) == -1)
3557 			return got_error_from_errno("asprintf");
3558 	} else {
3559 		path = de->d_name;
3560 	}
3561 
3562 	if (de->d_type != DT_DIR &&
3563 	    got_path_is_child(path, a->status_path, a->status_path_len)
3564 	    && !match_ignores(&a->ignores, path))
3565 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_UNVERSIONED,
3566 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3567 	if (parent_path[0])
3568 		free(path);
3569 	return err;
3570 }
3571 
3572 static const struct got_error *
3573 status_traverse(void *arg, const char *path, int dirfd)
3574 {
3575 	const struct got_error *err = NULL;
3576 	struct diff_dir_cb_arg *a = arg;
3577 
3578 	if (a->no_ignores)
3579 		return NULL;
3580 
3581 	err = add_ignores(&a->ignores, a->worktree->root_path,
3582 	    path, dirfd, ".cvsignore");
3583 	if (err)
3584 		return err;
3585 
3586 	err = add_ignores(&a->ignores, a->worktree->root_path, path,
3587 	    dirfd, ".gitignore");
3588 
3589 	return err;
3590 }
3591 
3592 static const struct got_error *
3593 report_single_file_status(const char *path, const char *ondisk_path,
3594 struct got_fileindex *fileindex, got_worktree_status_cb status_cb,
3595 void *status_arg, struct got_repository *repo, int report_unchanged)
3596 {
3597 	struct got_fileindex_entry *ie;
3598 	struct stat sb;
3599 
3600 	ie = got_fileindex_entry_get(fileindex, path, strlen(path));
3601 	if (ie)
3602 		return report_file_status(ie, ondisk_path, -1, NULL,
3603 		    status_cb, status_arg, repo, report_unchanged);
3604 
3605 	if (lstat(ondisk_path, &sb) == -1) {
3606 		if (errno != ENOENT)
3607 			return got_error_from_errno2("lstat", ondisk_path);
3608 		return (*status_cb)(status_arg, GOT_STATUS_NONEXISTENT,
3609 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3610 		return NULL;
3611 	}
3612 
3613 	if (S_ISREG(sb.st_mode) || S_ISLNK(sb.st_mode))
3614 		return (*status_cb)(status_arg, GOT_STATUS_UNVERSIONED,
3615 		    GOT_STATUS_NO_CHANGE, path, NULL, NULL, NULL, -1, NULL);
3616 
3617 	return NULL;
3618 }
3619 
3620 static const struct got_error *
3621 add_ignores_from_parent_paths(struct got_pathlist_head *ignores,
3622     const char *root_path, const char *path)
3623 {
3624 	const struct got_error *err;
3625 	char *parent_path, *next_parent_path = NULL;
3626 
3627 	err = add_ignores(ignores, root_path, "", -1,
3628 	    ".cvsignore");
3629 	if (err)
3630 		return err;
3631 
3632 	err = add_ignores(ignores, root_path, "", -1,
3633 	    ".gitignore");
3634 	if (err)
3635 		return err;
3636 
3637 	err = got_path_dirname(&parent_path, path);
3638 	if (err) {
3639 		if (err->code == GOT_ERR_BAD_PATH)
3640 			return NULL; /* cannot traverse parent */
3641 		return err;
3642 	}
3643 	for (;;) {
3644 		err = add_ignores(ignores, root_path, parent_path, -1,
3645 		    ".cvsignore");
3646 		if (err)
3647 			break;
3648 		err = add_ignores(ignores, root_path, parent_path, -1,
3649 		    ".gitignore");
3650 		if (err)
3651 			break;
3652 		err = got_path_dirname(&next_parent_path, parent_path);
3653 		if (err) {
3654 			if (err->code == GOT_ERR_BAD_PATH)
3655 				err = NULL; /* traversed everything */
3656 			break;
3657 		}
3658 		free(parent_path);
3659 		parent_path = next_parent_path;
3660 		next_parent_path = NULL;
3661 	}
3662 
3663 	free(parent_path);
3664 	free(next_parent_path);
3665 	return err;
3666 }
3667 
3668 static const struct got_error *
3669 worktree_status(struct got_worktree *worktree, const char *path,
3670     struct got_fileindex *fileindex, struct got_repository *repo,
3671     got_worktree_status_cb status_cb, void *status_arg,
3672     got_cancel_cb cancel_cb, void *cancel_arg, int no_ignores,
3673     int report_unchanged)
3674 {
3675 	const struct got_error *err = NULL;
3676 	int fd = -1;
3677 	struct got_fileindex_diff_dir_cb fdiff_cb;
3678 	struct diff_dir_cb_arg arg;
3679 	char *ondisk_path = NULL;
3680 
3681 	TAILQ_INIT(&arg.ignores);
3682 
3683 	if (asprintf(&ondisk_path, "%s%s%s",
3684 	    worktree->root_path, path[0] ? "/" : "", path) == -1)
3685 		return got_error_from_errno("asprintf");
3686 
3687 	fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW | O_DIRECTORY);
3688 	if (fd == -1) {
3689 		if (errno != ENOTDIR && errno != ENOENT && errno != EACCES &&
3690 		    errno != ELOOP)
3691 			err = got_error_from_errno2("open", ondisk_path);
3692 		else
3693 			err = report_single_file_status(path, ondisk_path,
3694 			    fileindex, status_cb, status_arg, repo,
3695 			    report_unchanged);
3696 	} else {
3697 		fdiff_cb.diff_old_new = status_old_new;
3698 		fdiff_cb.diff_old = status_old;
3699 		fdiff_cb.diff_new = status_new;
3700 		fdiff_cb.diff_traverse = status_traverse;
3701 		arg.fileindex = fileindex;
3702 		arg.worktree = worktree;
3703 		arg.status_path = path;
3704 		arg.status_path_len = strlen(path);
3705 		arg.repo = repo;
3706 		arg.status_cb = status_cb;
3707 		arg.status_arg = status_arg;
3708 		arg.cancel_cb = cancel_cb;
3709 		arg.cancel_arg = cancel_arg;
3710 		arg.report_unchanged = report_unchanged;
3711 		arg.no_ignores = no_ignores;
3712 		if (!no_ignores) {
3713 			err = add_ignores_from_parent_paths(&arg.ignores,
3714 			    worktree->root_path, path);
3715 			if (err)
3716 				goto done;
3717 		}
3718 		err = got_fileindex_diff_dir(fileindex, fd,
3719 		    worktree->root_path, path, repo, &fdiff_cb, &arg);
3720 	}
3721 done:
3722 	free_ignores(&arg.ignores);
3723 	if (fd != -1 && close(fd) == -1 && err == NULL)
3724 		err = got_error_from_errno("close");
3725 	free(ondisk_path);
3726 	return err;
3727 }
3728 
3729 const struct got_error *
3730 got_worktree_status(struct got_worktree *worktree,
3731     struct got_pathlist_head *paths, struct got_repository *repo,
3732     got_worktree_status_cb status_cb, void *status_arg,
3733     got_cancel_cb cancel_cb, void *cancel_arg)
3734 {
3735 	const struct got_error *err = NULL;
3736 	char *fileindex_path = NULL;
3737 	struct got_fileindex *fileindex = NULL;
3738 	struct got_pathlist_entry *pe;
3739 
3740 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3741 	if (err)
3742 		return err;
3743 
3744 	TAILQ_FOREACH(pe, paths, entry) {
3745 		err = worktree_status(worktree, pe->path, fileindex, repo,
3746 			status_cb, status_arg, cancel_cb, cancel_arg, 0, 0);
3747 		if (err)
3748 			break;
3749 	}
3750 	free(fileindex_path);
3751 	got_fileindex_free(fileindex);
3752 	return err;
3753 }
3754 
3755 const struct got_error *
3756 got_worktree_resolve_path(char **wt_path, struct got_worktree *worktree,
3757     const char *arg)
3758 {
3759 	const struct got_error *err = NULL;
3760 	char *resolved = NULL, *cwd = NULL, *path = NULL;
3761 	size_t len;
3762 	struct stat sb;
3763 	char *abspath = NULL;
3764 	char canonpath[PATH_MAX];
3765 
3766 	*wt_path = NULL;
3767 
3768 	cwd = getcwd(NULL, 0);
3769 	if (cwd == NULL)
3770 		return got_error_from_errno("getcwd");
3771 
3772 	if (lstat(arg, &sb) == -1) {
3773 		if (errno != ENOENT) {
3774 			err = got_error_from_errno2("lstat", arg);
3775 			goto done;
3776 		}
3777 		sb.st_mode = 0;
3778 	}
3779 	if (S_ISLNK(sb.st_mode)) {
3780 		/*
3781 		 * We cannot use realpath(3) with symlinks since we want to
3782 		 * operate on the symlink itself.
3783 		 * But we can make the path absolute, assuming it is relative
3784 		 * to the current working directory, and then canonicalize it.
3785 		 */
3786 		if (!got_path_is_absolute(arg)) {
3787 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3788 				err = got_error_from_errno("asprintf");
3789 				goto done;
3790 			}
3791 
3792 		}
3793 		err = got_canonpath(abspath ? abspath : arg, canonpath,
3794 		    sizeof(canonpath));
3795 		if (err)
3796 			goto done;
3797 		resolved = strdup(canonpath);
3798 		if (resolved == NULL) {
3799 			err = got_error_from_errno("strdup");
3800 			goto done;
3801 		}
3802 	} else {
3803 		resolved = realpath(arg, NULL);
3804 		if (resolved == NULL) {
3805 			if (errno != ENOENT) {
3806 				err = got_error_from_errno2("realpath", arg);
3807 				goto done;
3808 			}
3809 			if (asprintf(&abspath, "%s/%s", cwd, arg) == -1) {
3810 				err = got_error_from_errno("asprintf");
3811 				goto done;
3812 			}
3813 			err = got_canonpath(abspath, canonpath,
3814 			    sizeof(canonpath));
3815 			if (err)
3816 				goto done;
3817 			resolved = strdup(canonpath);
3818 			if (resolved == NULL) {
3819 				err = got_error_from_errno("strdup");
3820 				goto done;
3821 			}
3822 		}
3823 	}
3824 
3825 	if (strncmp(got_worktree_get_root_path(worktree), resolved,
3826 	    strlen(got_worktree_get_root_path(worktree)))) {
3827 		err = got_error_path(resolved, GOT_ERR_BAD_PATH);
3828 		goto done;
3829 	}
3830 
3831 	if (strlen(resolved) > strlen(got_worktree_get_root_path(worktree))) {
3832 		err = got_path_skip_common_ancestor(&path,
3833 		    got_worktree_get_root_path(worktree), resolved);
3834 		if (err)
3835 			goto done;
3836 	} else {
3837 		path = strdup("");
3838 		if (path == NULL) {
3839 			err = got_error_from_errno("strdup");
3840 			goto done;
3841 		}
3842 	}
3843 
3844 	/* XXX status walk can't deal with trailing slash! */
3845 	len = strlen(path);
3846 	while (len > 0 && path[len - 1] == '/') {
3847 		path[len - 1] = '\0';
3848 		len--;
3849 	}
3850 done:
3851 	free(abspath);
3852 	free(resolved);
3853 	free(cwd);
3854 	if (err == NULL)
3855 		*wt_path = path;
3856 	else
3857 		free(path);
3858 	return err;
3859 }
3860 
3861 struct schedule_addition_args {
3862 	struct got_worktree *worktree;
3863 	struct got_fileindex *fileindex;
3864 	got_worktree_checkout_cb progress_cb;
3865 	void *progress_arg;
3866 	struct got_repository *repo;
3867 };
3868 
3869 static const struct got_error *
3870 schedule_addition(void *arg, unsigned char status, unsigned char staged_status,
3871     const char *relpath, struct got_object_id *blob_id,
3872     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
3873     int dirfd, const char *de_name)
3874 {
3875 	struct schedule_addition_args *a = arg;
3876 	const struct got_error *err = NULL;
3877 	struct got_fileindex_entry *ie;
3878 	struct stat sb;
3879 	char *ondisk_path;
3880 
3881 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
3882 	    relpath) == -1)
3883 		return got_error_from_errno("asprintf");
3884 
3885 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
3886 	if (ie) {
3887 		err = get_file_status(&status, &sb, ie, ondisk_path, dirfd,
3888 		    de_name, a->repo);
3889 		if (err)
3890 			goto done;
3891 		/* Re-adding an existing entry is a no-op. */
3892 		if (status == GOT_STATUS_ADD)
3893 			goto done;
3894 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
3895 		if (err)
3896 			goto done;
3897 	}
3898 
3899 	if (status != GOT_STATUS_UNVERSIONED) {
3900 		err = got_error_path(ondisk_path, GOT_ERR_FILE_STATUS);
3901 		goto done;
3902 	}
3903 
3904 	err = got_fileindex_entry_alloc(&ie, relpath);
3905 	if (err)
3906 		goto done;
3907 	err = got_fileindex_entry_update(ie, a->worktree->root_fd,
3908 	    relpath, NULL, NULL, 1);
3909 	if (err) {
3910 		got_fileindex_entry_free(ie);
3911 		goto done;
3912 	}
3913 	err = got_fileindex_entry_add(a->fileindex, ie);
3914 	if (err) {
3915 		got_fileindex_entry_free(ie);
3916 		goto done;
3917 	}
3918 done:
3919 	free(ondisk_path);
3920 	if (err)
3921 		return err;
3922 	if (status == GOT_STATUS_ADD)
3923 		return NULL;
3924 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_ADD, relpath);
3925 }
3926 
3927 const struct got_error *
3928 got_worktree_schedule_add(struct got_worktree *worktree,
3929     struct got_pathlist_head *paths,
3930     got_worktree_checkout_cb progress_cb, void *progress_arg,
3931     struct got_repository *repo, int no_ignores)
3932 {
3933 	struct got_fileindex *fileindex = NULL;
3934 	char *fileindex_path = NULL;
3935 	const struct got_error *err = NULL, *sync_err, *unlockerr;
3936 	struct got_pathlist_entry *pe;
3937 	struct schedule_addition_args saa;
3938 
3939 	err = lock_worktree(worktree, LOCK_EX);
3940 	if (err)
3941 		return err;
3942 
3943 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
3944 	if (err)
3945 		goto done;
3946 
3947 	saa.worktree = worktree;
3948 	saa.fileindex = fileindex;
3949 	saa.progress_cb = progress_cb;
3950 	saa.progress_arg = progress_arg;
3951 	saa.repo = repo;
3952 
3953 	TAILQ_FOREACH(pe, paths, entry) {
3954 		err = worktree_status(worktree, pe->path, fileindex, repo,
3955 			schedule_addition, &saa, NULL, NULL, no_ignores, 0);
3956 		if (err)
3957 			break;
3958 	}
3959 	sync_err = sync_fileindex(fileindex, fileindex_path);
3960 	if (sync_err && err == NULL)
3961 		err = sync_err;
3962 done:
3963 	free(fileindex_path);
3964 	if (fileindex)
3965 		got_fileindex_free(fileindex);
3966 	unlockerr = lock_worktree(worktree, LOCK_SH);
3967 	if (unlockerr && err == NULL)
3968 		err = unlockerr;
3969 	return err;
3970 }
3971 
3972 struct schedule_deletion_args {
3973 	struct got_worktree *worktree;
3974 	struct got_fileindex *fileindex;
3975 	got_worktree_delete_cb progress_cb;
3976 	void *progress_arg;
3977 	struct got_repository *repo;
3978 	int delete_local_mods;
3979 	int keep_on_disk;
3980 	const char *status_codes;
3981 };
3982 
3983 static const struct got_error *
3984 schedule_for_deletion(void *arg, unsigned char status,
3985     unsigned char staged_status, const char *relpath,
3986     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
3987     struct got_object_id *commit_id, int dirfd, const char *de_name)
3988 {
3989 	struct schedule_deletion_args *a = arg;
3990 	const struct got_error *err = NULL;
3991 	struct got_fileindex_entry *ie = NULL;
3992 	struct stat sb;
3993 	char *ondisk_path;
3994 
3995 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
3996 	if (ie == NULL)
3997 		return got_error_path(relpath, GOT_ERR_BAD_PATH);
3998 
3999 	staged_status = get_staged_status(ie);
4000 	if (staged_status != GOT_STATUS_NO_CHANGE) {
4001 		if (staged_status == GOT_STATUS_DELETE)
4002 			return NULL;
4003 		return got_error_path(relpath, GOT_ERR_FILE_STAGED);
4004 	}
4005 
4006 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
4007 	    relpath) == -1)
4008 		return got_error_from_errno("asprintf");
4009 
4010 	err = get_file_status(&status, &sb, ie, ondisk_path, dirfd, de_name,
4011 	    a->repo);
4012 	if (err)
4013 		goto done;
4014 
4015 	if (a->status_codes) {
4016 		size_t ncodes = strlen(a->status_codes);
4017 		int i;
4018 		for (i = 0; i < ncodes ; i++) {
4019 			if (status == a->status_codes[i])
4020 				break;
4021 		}
4022 		if (i == ncodes) { 
4023 			/* Do not delete files in non-matching status. */
4024 			free(ondisk_path);
4025 			return NULL;
4026 		}
4027 		if (a->status_codes[i] != GOT_STATUS_MODIFY &&
4028 		    a->status_codes[i] != GOT_STATUS_MISSING) {
4029 			static char msg[64];
4030 			snprintf(msg, sizeof(msg),
4031 			    "invalid status code '%c'", a->status_codes[i]);
4032 			err = got_error_msg(GOT_ERR_FILE_STATUS, msg);
4033 			goto done;
4034 		}
4035 	}
4036 
4037 	if (status != GOT_STATUS_NO_CHANGE) {
4038 		if (status == GOT_STATUS_DELETE)
4039 			goto done;
4040 		if (status == GOT_STATUS_MODIFY && !a->delete_local_mods) {
4041 			err = got_error_path(relpath, GOT_ERR_FILE_MODIFIED);
4042 			goto done;
4043 		}
4044 		if (status != GOT_STATUS_MODIFY &&
4045 		    status != GOT_STATUS_MISSING) {
4046 			err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
4047 			goto done;
4048 		}
4049 	}
4050 
4051 	if (!a->keep_on_disk && status != GOT_STATUS_MISSING) {
4052 		size_t root_len;
4053 
4054 		if (dirfd != -1) {
4055 			if (unlinkat(dirfd, de_name, 0) != 0) {
4056 				err = got_error_from_errno2("unlinkat",
4057 				    ondisk_path);
4058 				goto done;
4059 			}
4060 		} else if (unlink(ondisk_path) != 0) {
4061 			err = got_error_from_errno2("unlink", ondisk_path);
4062 			goto done;
4063 		}
4064 
4065 		root_len = strlen(a->worktree->root_path);
4066 		do {
4067 			char *parent;
4068 			err = got_path_dirname(&parent, ondisk_path);
4069 			if (err)
4070 				goto done;
4071 			free(ondisk_path);
4072 			ondisk_path = parent;
4073 			if (rmdir(ondisk_path) == -1) {
4074 				if (errno != ENOTEMPTY)
4075 					err = got_error_from_errno2("rmdir",
4076 					    ondisk_path);
4077 				break;
4078 			}
4079 		} while (got_path_cmp(ondisk_path, a->worktree->root_path,
4080 		    strlen(ondisk_path), root_len) != 0);
4081 	}
4082 
4083 	got_fileindex_entry_mark_deleted_from_disk(ie);
4084 done:
4085 	free(ondisk_path);
4086 	if (err)
4087 		return err;
4088 	if (status == GOT_STATUS_DELETE)
4089 		return NULL;
4090 	return (*a->progress_cb)(a->progress_arg, GOT_STATUS_DELETE,
4091 	    staged_status, relpath);
4092 }
4093 
4094 const struct got_error *
4095 got_worktree_schedule_delete(struct got_worktree *worktree,
4096     struct got_pathlist_head *paths, int delete_local_mods,
4097     const char *status_codes,
4098     got_worktree_delete_cb progress_cb, void *progress_arg,
4099     struct got_repository *repo, int keep_on_disk)
4100 {
4101 	struct got_fileindex *fileindex = NULL;
4102 	char *fileindex_path = NULL;
4103 	const struct got_error *err = NULL, *sync_err, *unlockerr;
4104 	struct got_pathlist_entry *pe;
4105 	struct schedule_deletion_args sda;
4106 
4107 	err = lock_worktree(worktree, LOCK_EX);
4108 	if (err)
4109 		return err;
4110 
4111 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4112 	if (err)
4113 		goto done;
4114 
4115 	sda.worktree = worktree;
4116 	sda.fileindex = fileindex;
4117 	sda.progress_cb = progress_cb;
4118 	sda.progress_arg = progress_arg;
4119 	sda.repo = repo;
4120 	sda.delete_local_mods = delete_local_mods;
4121 	sda.keep_on_disk = keep_on_disk;
4122 	sda.status_codes = status_codes;
4123 
4124 	TAILQ_FOREACH(pe, paths, entry) {
4125 		err = worktree_status(worktree, pe->path, fileindex, repo,
4126 			schedule_for_deletion, &sda, NULL, NULL, 0, 1);
4127 		if (err)
4128 			break;
4129 	}
4130 	sync_err = sync_fileindex(fileindex, fileindex_path);
4131 	if (sync_err && err == NULL)
4132 		err = sync_err;
4133 done:
4134 	free(fileindex_path);
4135 	if (fileindex)
4136 		got_fileindex_free(fileindex);
4137 	unlockerr = lock_worktree(worktree, LOCK_SH);
4138 	if (unlockerr && err == NULL)
4139 		err = unlockerr;
4140 	return err;
4141 }
4142 
4143 static const struct got_error *
4144 copy_one_line(FILE *infile, FILE *outfile, FILE *rejectfile)
4145 {
4146 	const struct got_error *err = NULL;
4147 	char *line = NULL;
4148 	size_t linesize = 0, n;
4149 	ssize_t linelen;
4150 
4151 	linelen = getline(&line, &linesize, infile);
4152 	if (linelen == -1) {
4153 		if (ferror(infile)) {
4154 			err = got_error_from_errno("getline");
4155 			goto done;
4156 		}
4157 		return NULL;
4158 	}
4159 	if (outfile) {
4160 		n = fwrite(line, 1, linelen, outfile);
4161 		if (n != linelen) {
4162 			err = got_ferror(outfile, GOT_ERR_IO);
4163 			goto done;
4164 		}
4165 	}
4166 	if (rejectfile) {
4167 		n = fwrite(line, 1, linelen, rejectfile);
4168 		if (n != linelen)
4169 			err = got_ferror(outfile, GOT_ERR_IO);
4170 	}
4171 done:
4172 	free(line);
4173 	return err;
4174 }
4175 
4176 static const struct got_error *
4177 skip_one_line(FILE *f)
4178 {
4179 	char *line = NULL;
4180 	size_t linesize = 0;
4181 	ssize_t linelen;
4182 
4183 	linelen = getline(&line, &linesize, f);
4184 	if (linelen == -1) {
4185 		if (ferror(f))
4186 			return got_error_from_errno("getline");
4187 		return NULL;
4188 	}
4189 	free(line);
4190 	return NULL;
4191 }
4192 
4193 static const struct got_error *
4194 copy_change(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4195     int start_old, int end_old, int start_new, int end_new,
4196     FILE *outfile, FILE *rejectfile)
4197  {
4198 	const struct got_error *err;
4199 
4200 	/* Copy old file's lines leading up to patch. */
4201 	while (!feof(f1) && *line_cur1 < start_old) {
4202 		err = copy_one_line(f1, outfile, NULL);
4203 		if (err)
4204 			return err;
4205 		(*line_cur1)++;
4206 	}
4207 	/* Skip new file's lines leading up to patch. */
4208 	while (!feof(f2) && *line_cur2 < start_new) {
4209 		if (rejectfile)
4210 			err = copy_one_line(f2, NULL, rejectfile);
4211 		else
4212 			err = skip_one_line(f2);
4213 		if (err)
4214 			return err;
4215 		(*line_cur2)++;
4216 	}
4217 	/* Copy patched lines. */
4218 	while (!feof(f2) && *line_cur2 <= end_new) {
4219 		err = copy_one_line(f2, outfile, NULL);
4220 		if (err)
4221 			return err;
4222 		(*line_cur2)++;
4223 	}
4224 	/* Skip over old file's replaced lines. */
4225 	while (!feof(f1) && *line_cur1 <= end_old) {
4226 		if (rejectfile)
4227 			err = copy_one_line(f1, NULL, rejectfile);
4228 		else
4229 			err = skip_one_line(f1);
4230 		if (err)
4231 			return err;
4232 		(*line_cur1)++;
4233 	}
4234 
4235 	return NULL;
4236 }
4237 
4238 static const struct got_error *
4239 copy_remaining_content(FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4240     FILE *outfile, FILE *rejectfile)
4241 {
4242 	const struct got_error *err;
4243 
4244 	if (outfile) {
4245 		/* Copy old file's lines until EOF. */
4246 		while (!feof(f1)) {
4247 			err = copy_one_line(f1, outfile, NULL);
4248 			if (err)
4249 				return err;
4250 			(*line_cur1)++;
4251 		}
4252 	}
4253 	if (rejectfile) {
4254 		/* Copy new file's lines until EOF. */
4255 		while (!feof(f2)) {
4256 			err = copy_one_line(f2, NULL, rejectfile);
4257 			if (err)
4258 				return err;
4259 			(*line_cur2)++;
4260 		}
4261 	}
4262 
4263 	return NULL;
4264 }
4265 
4266 static const struct got_error *
4267 apply_or_reject_change(int *choice, int *nchunks_used,
4268     struct diff_result *diff_result, int n,
4269     const char *relpath, FILE *f1, FILE *f2, int *line_cur1, int *line_cur2,
4270     FILE *outfile, FILE *rejectfile, int changeno, int nchanges,
4271     got_worktree_patch_cb patch_cb, void *patch_arg)
4272 {
4273 	const struct got_error *err = NULL;
4274 	struct diff_chunk_context cc = {}; 
4275 	int start_old, end_old, start_new, end_new;
4276 	FILE *hunkfile;
4277 	struct diff_output_unidiff_state *diff_state;
4278 	struct diff_input_info diff_info;
4279 	int rc;
4280 
4281 	*choice = GOT_PATCH_CHOICE_NONE;
4282 
4283 	/* Get changed line numbers without context lines for copy_change(). */
4284 	diff_chunk_context_load_change(&cc, NULL, diff_result, n, 0);
4285 	start_old = cc.left.start;
4286 	end_old = cc.left.end;
4287 	start_new = cc.right.start;
4288 	end_new = cc.right.end;
4289 
4290 	/* Get the same change with context lines for display. */
4291 	memset(&cc, 0, sizeof(cc));
4292 	diff_chunk_context_load_change(&cc, nchunks_used, diff_result, n, 3);
4293 
4294 	memset(&diff_info, 0, sizeof(diff_info));
4295 	diff_info.left_path = relpath;
4296 	diff_info.right_path = relpath;
4297 
4298 	diff_state = diff_output_unidiff_state_alloc();
4299 	if (diff_state == NULL)
4300 		return got_error_set_errno(ENOMEM,
4301 		    "diff_output_unidiff_state_alloc");
4302 
4303 	hunkfile = got_opentemp();
4304 	if (hunkfile == NULL) {
4305 		err = got_error_from_errno("got_opentemp");
4306 		goto done;
4307 	}
4308 
4309 	rc = diff_output_unidiff_chunk(NULL, hunkfile, diff_state, &diff_info,
4310 	    diff_result, &cc);
4311 	if (rc != DIFF_RC_OK) {
4312 		err = got_error_set_errno(rc, "diff_output_unidiff_chunk");
4313 		goto done;
4314 	}
4315 
4316 	if (fseek(hunkfile, 0L, SEEK_SET) == -1) {
4317 		err = got_ferror(hunkfile, GOT_ERR_IO);
4318 		goto done;
4319 	}
4320 
4321 	err = (*patch_cb)(choice, patch_arg, GOT_STATUS_MODIFY, relpath,
4322 	    hunkfile, changeno, nchanges);
4323 	if (err)
4324 		goto done;
4325 
4326 	switch (*choice) {
4327 	case GOT_PATCH_CHOICE_YES:
4328 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4329 		    end_old, start_new, end_new, outfile, rejectfile);
4330 		break;
4331 	case GOT_PATCH_CHOICE_NO:
4332 		err = copy_change(f1, f2, line_cur1, line_cur2, start_old,
4333 		    end_old, start_new, end_new, rejectfile, outfile);
4334 		break;
4335 	case GOT_PATCH_CHOICE_QUIT:
4336 		break;
4337 	default:
4338 		err = got_error(GOT_ERR_PATCH_CHOICE);
4339 		break;
4340 	}
4341 done:
4342 	diff_output_unidiff_state_free(diff_state);
4343 	if (hunkfile && fclose(hunkfile) == EOF && err == NULL)
4344 		err = got_error_from_errno("fclose");
4345 	return err;
4346 }
4347 
4348 struct revert_file_args {
4349 	struct got_worktree *worktree;
4350 	struct got_fileindex *fileindex;
4351 	got_worktree_checkout_cb progress_cb;
4352 	void *progress_arg;
4353 	got_worktree_patch_cb patch_cb;
4354 	void *patch_arg;
4355 	struct got_repository *repo;
4356 };
4357 
4358 static const struct got_error *
4359 create_patched_content(char **path_outfile, int reverse_patch,
4360     struct got_object_id *blob_id, const char *path2,
4361     int dirfd2, const char *de_name2,
4362     const char *relpath, struct got_repository *repo,
4363     got_worktree_patch_cb patch_cb, void *patch_arg)
4364 {
4365 	const struct got_error *err, *free_err;
4366 	struct got_blob_object *blob = NULL;
4367 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL;
4368 	int fd2 = -1;
4369 	char link_target[PATH_MAX];
4370 	ssize_t link_len = 0;
4371 	char *path1 = NULL, *id_str = NULL;
4372 	struct stat sb2;
4373 	struct got_diffreg_result *diffreg_result = NULL;
4374 	int line_cur1 = 1, line_cur2 = 1, have_content = 0;
4375 	int i = 0, n = 0, nchunks_used = 0, nchanges = 0;
4376 
4377 	*path_outfile = NULL;
4378 
4379 	err = got_object_id_str(&id_str, blob_id);
4380 	if (err)
4381 		return err;
4382 
4383 	if (dirfd2 != -1) {
4384 		fd2 = openat(dirfd2, de_name2, O_RDONLY | O_NOFOLLOW);
4385 		if (fd2 == -1) {
4386 			if (errno != ELOOP) {
4387 				err = got_error_from_errno2("openat", path2);
4388 				goto done;
4389 			}
4390 			link_len = readlinkat(dirfd2, de_name2,
4391 			    link_target, sizeof(link_target));
4392 			if (link_len == -1)
4393 				return got_error_from_errno2("readlinkat", path2);
4394 			sb2.st_mode = S_IFLNK;
4395 			sb2.st_size = link_len;
4396 		}
4397 	} else {
4398 		fd2 = open(path2, O_RDONLY | O_NOFOLLOW);
4399 		if (fd2 == -1) {
4400 			if (errno != ELOOP) {
4401 				err = got_error_from_errno2("open", path2);
4402 				goto done;
4403 			}
4404 			link_len = readlink(path2, link_target,
4405 			    sizeof(link_target));
4406 			if (link_len == -1)
4407 				return got_error_from_errno2("readlink", path2);
4408 			sb2.st_mode = S_IFLNK;
4409 			sb2.st_size = link_len;
4410 		}
4411 	}
4412 	if (fd2 != -1) {
4413 		if (fstat(fd2, &sb2) == -1) {
4414 			err = got_error_from_errno2("fstat", path2);
4415 			goto done;
4416 		}
4417 
4418 		f2 = fdopen(fd2, "r");
4419 		if (f2 == NULL) {
4420 			err = got_error_from_errno2("fdopen", path2);
4421 			goto done;
4422 		}
4423 		fd2 = -1;
4424 	} else {
4425 		size_t n;
4426 		f2 = got_opentemp();
4427 		if (f2 == NULL) {
4428 			err = got_error_from_errno2("got_opentemp", path2);
4429 			goto done;
4430 		}
4431 		n = fwrite(link_target, 1, link_len, f2);
4432 		if (n != link_len) {
4433 			err = got_ferror(f2, GOT_ERR_IO);
4434 			goto done;
4435 		}
4436 		if (fflush(f2) == EOF) {
4437 			err = got_error_from_errno("fflush");
4438 			goto done;
4439 		}
4440 		rewind(f2);
4441 	}
4442 
4443 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192);
4444 	if (err)
4445 		goto done;
4446 
4447 	err = got_opentemp_named(&path1, &f1, "got-patched-blob");
4448 	if (err)
4449 		goto done;
4450 
4451 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
4452 	if (err)
4453 		goto done;
4454 
4455 	err = got_diff_files(&diffreg_result, f1, id_str, f2, path2, 3, 0, 1,
4456 	    NULL);
4457 	if (err)
4458 		goto done;
4459 
4460 	err = got_opentemp_named(path_outfile, &outfile, "got-patched-content");
4461 	if (err)
4462 		goto done;
4463 
4464 	if (fseek(f1, 0L, SEEK_SET) == -1)
4465 		return got_ferror(f1, GOT_ERR_IO);
4466 	if (fseek(f2, 0L, SEEK_SET) == -1)
4467 		return got_ferror(f2, GOT_ERR_IO);
4468 
4469 	/* Count the number of actual changes in the diff result. */
4470 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4471 		struct diff_chunk_context cc = {}; 
4472 		diff_chunk_context_load_change(&cc, &nchunks_used,
4473 		    diffreg_result->result, n, 0);
4474 		nchanges++;
4475 	}
4476 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
4477 		int choice;
4478 		err = apply_or_reject_change(&choice, &nchunks_used,
4479 		    diffreg_result->result, n, relpath, f1, f2,
4480 		    &line_cur1, &line_cur2,
4481 		    reverse_patch ? NULL : outfile,
4482 		    reverse_patch ? outfile : NULL,
4483 		    ++i, nchanges, patch_cb, patch_arg);
4484 		if (err)
4485 			goto done;
4486 		if (choice == GOT_PATCH_CHOICE_YES)
4487 			have_content = 1;
4488 		else if (choice == GOT_PATCH_CHOICE_QUIT)
4489 			break;
4490 	}
4491 	if (have_content) {
4492 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
4493 		    reverse_patch ? NULL : outfile,
4494 		    reverse_patch ? outfile : NULL);
4495 		if (err)
4496 			goto done;
4497 
4498 		if (!S_ISLNK(sb2.st_mode)) {
4499 			if (fchmod(fileno(outfile), sb2.st_mode) == -1) {
4500 				err = got_error_from_errno2("fchmod", path2);
4501 				goto done;
4502 			}
4503 		}
4504 	}
4505 done:
4506 	free(id_str);
4507 	if (blob)
4508 		got_object_blob_close(blob);
4509 	free_err = got_diffreg_result_free(diffreg_result);
4510 	if (err == NULL)
4511 		err = free_err;
4512 	if (f1 && fclose(f1) == EOF && err == NULL)
4513 		err = got_error_from_errno2("fclose", path1);
4514 	if (f2 && fclose(f2) == EOF && err == NULL)
4515 		err = got_error_from_errno2("fclose", path2);
4516 	if (fd2 != -1 && close(fd2) == -1 && err == NULL)
4517 		err = got_error_from_errno2("close", path2);
4518 	if (outfile && fclose(outfile) == EOF && err == NULL)
4519 		err = got_error_from_errno2("fclose", *path_outfile);
4520 	if (path1 && unlink(path1) == -1 && err == NULL)
4521 		err = got_error_from_errno2("unlink", path1);
4522 	if (err || !have_content) {
4523 		if (*path_outfile && unlink(*path_outfile) == -1 && err == NULL)
4524 			err = got_error_from_errno2("unlink", *path_outfile);
4525 		free(*path_outfile);
4526 		*path_outfile = NULL;
4527 	}
4528 	free(path1);
4529 	return err;
4530 }
4531 
4532 static const struct got_error *
4533 revert_file(void *arg, unsigned char status, unsigned char staged_status,
4534     const char *relpath, struct got_object_id *blob_id,
4535     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
4536     int dirfd, const char *de_name)
4537 {
4538 	struct revert_file_args *a = arg;
4539 	const struct got_error *err = NULL;
4540 	char *parent_path = NULL;
4541 	struct got_fileindex_entry *ie;
4542 	struct got_tree_object *tree = NULL;
4543 	struct got_object_id *tree_id = NULL;
4544 	const struct got_tree_entry *te = NULL;
4545 	char *tree_path = NULL, *te_name;
4546 	char *ondisk_path = NULL, *path_content = NULL;
4547 	struct got_blob_object *blob = NULL;
4548 
4549 	/* Reverting a staged deletion is a no-op. */
4550 	if (status == GOT_STATUS_DELETE &&
4551 	    staged_status != GOT_STATUS_NO_CHANGE)
4552 		return NULL;
4553 
4554 	if (status == GOT_STATUS_UNVERSIONED)
4555 		return (*a->progress_cb)(a->progress_arg,
4556 		    GOT_STATUS_UNVERSIONED, relpath);
4557 
4558 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
4559 	if (ie == NULL)
4560 		return got_error_path(relpath, GOT_ERR_BAD_PATH);
4561 
4562 	/* Construct in-repository path of tree which contains this blob. */
4563 	err = got_path_dirname(&parent_path, ie->path);
4564 	if (err) {
4565 		if (err->code != GOT_ERR_BAD_PATH)
4566 			goto done;
4567 		parent_path = strdup("/");
4568 		if (parent_path == NULL) {
4569 			err = got_error_from_errno("strdup");
4570 			goto done;
4571 		}
4572 	}
4573 	if (got_path_is_root_dir(a->worktree->path_prefix)) {
4574 		tree_path = strdup(parent_path);
4575 		if (tree_path == NULL) {
4576 			err = got_error_from_errno("strdup");
4577 			goto done;
4578 		}
4579 	} else {
4580 		if (got_path_is_root_dir(parent_path)) {
4581 			tree_path = strdup(a->worktree->path_prefix);
4582 			if (tree_path == NULL) {
4583 				err = got_error_from_errno("strdup");
4584 				goto done;
4585 			}
4586 		} else {
4587 			if (asprintf(&tree_path, "%s/%s",
4588 			    a->worktree->path_prefix, parent_path) == -1) {
4589 				err = got_error_from_errno("asprintf");
4590 				goto done;
4591 			}
4592 		}
4593 	}
4594 
4595 	err = got_object_id_by_path(&tree_id, a->repo,
4596 	    a->worktree->base_commit_id, tree_path);
4597 	if (err) {
4598 		if (!(err->code == GOT_ERR_NO_TREE_ENTRY &&
4599 		    (status == GOT_STATUS_ADD ||
4600 		    staged_status == GOT_STATUS_ADD)))
4601 			goto done;
4602 	} else {
4603 		err = got_object_open_as_tree(&tree, a->repo, tree_id);
4604 		if (err)
4605 			goto done;
4606 
4607 		err = got_path_basename(&te_name, ie->path);
4608 		if (err)
4609 			goto done;
4610 
4611 		te = got_object_tree_find_entry(tree, te_name);
4612 		free(te_name);
4613 		if (te == NULL && status != GOT_STATUS_ADD &&
4614 		    staged_status != GOT_STATUS_ADD) {
4615 			err = got_error_path(ie->path, GOT_ERR_NO_TREE_ENTRY);
4616 			goto done;
4617 		}
4618 	}
4619 
4620 	switch (status) {
4621 	case GOT_STATUS_ADD:
4622 		if (a->patch_cb) {
4623 			int choice = GOT_PATCH_CHOICE_NONE;
4624 			err = (*a->patch_cb)(&choice, a->patch_arg,
4625 			    status, ie->path, NULL, 1, 1);
4626 			if (err)
4627 				goto done;
4628 			if (choice != GOT_PATCH_CHOICE_YES)
4629 				break;
4630 		}
4631 		err = (*a->progress_cb)(a->progress_arg, GOT_STATUS_REVERT,
4632 		    ie->path);
4633 		if (err)
4634 			goto done;
4635 		got_fileindex_entry_remove(a->fileindex, ie);
4636 		break;
4637 	case GOT_STATUS_DELETE:
4638 		if (a->patch_cb) {
4639 			int choice = GOT_PATCH_CHOICE_NONE;
4640 			err = (*a->patch_cb)(&choice, a->patch_arg,
4641 			    status, ie->path, NULL, 1, 1);
4642 			if (err)
4643 				goto done;
4644 			if (choice != GOT_PATCH_CHOICE_YES)
4645 				break;
4646 		}
4647 		/* fall through */
4648 	case GOT_STATUS_MODIFY:
4649 	case GOT_STATUS_MODE_CHANGE:
4650 	case GOT_STATUS_CONFLICT:
4651 	case GOT_STATUS_MISSING: {
4652 		struct got_object_id id;
4653 		if (staged_status == GOT_STATUS_ADD ||
4654 		    staged_status == GOT_STATUS_MODIFY) {
4655 			memcpy(id.sha1, ie->staged_blob_sha1,
4656 			    SHA1_DIGEST_LENGTH);
4657 		} else
4658 			memcpy(id.sha1, ie->blob_sha1,
4659 			    SHA1_DIGEST_LENGTH);
4660 		err = got_object_open_as_blob(&blob, a->repo, &id, 8192);
4661 		if (err)
4662 			goto done;
4663 
4664 		if (asprintf(&ondisk_path, "%s/%s",
4665 		    got_worktree_get_root_path(a->worktree), relpath) == -1) {
4666 			err = got_error_from_errno("asprintf");
4667 			goto done;
4668 		}
4669 
4670 		if (a->patch_cb && (status == GOT_STATUS_MODIFY ||
4671 		    status == GOT_STATUS_CONFLICT)) {
4672 			int is_bad_symlink = 0;
4673 			err = create_patched_content(&path_content, 1, &id,
4674 			    ondisk_path, dirfd, de_name, ie->path, a->repo,
4675 			    a->patch_cb, a->patch_arg);
4676 			if (err || path_content == NULL)
4677 				break;
4678 			if (te && S_ISLNK(te->mode)) {
4679 				if (unlink(path_content) == -1) {
4680 					err = got_error_from_errno2("unlink",
4681 					    path_content);
4682 					break;
4683 				}
4684 				err = install_symlink(&is_bad_symlink,
4685 				    a->worktree, ondisk_path, ie->path,
4686 				    blob, 0, 1, 0, a->repo,
4687 				    a->progress_cb, a->progress_arg);
4688 			} else {
4689 				if (rename(path_content, ondisk_path) == -1) {
4690 					err = got_error_from_errno3("rename",
4691 					    path_content, ondisk_path);
4692 					goto done;
4693 				}
4694 			}
4695 		} else {
4696 			int is_bad_symlink = 0;
4697 			if (te && S_ISLNK(te->mode)) {
4698 				err = install_symlink(&is_bad_symlink,
4699 				    a->worktree, ondisk_path, ie->path,
4700 				    blob, 0, 1, 0, a->repo,
4701 				    a->progress_cb, a->progress_arg);
4702 			} else {
4703 				err = install_blob(a->worktree, ondisk_path,
4704 				    ie->path,
4705 				    te ? te->mode : GOT_DEFAULT_FILE_MODE,
4706 				    got_fileindex_perms_to_st(ie), blob,
4707 				    0, 1, 0, 0, a->repo,
4708 				    a->progress_cb, a->progress_arg);
4709 			}
4710 			if (err)
4711 				goto done;
4712 			if (status == GOT_STATUS_DELETE ||
4713 			    status == GOT_STATUS_MODE_CHANGE) {
4714 				err = got_fileindex_entry_update(ie,
4715 				    a->worktree->root_fd, relpath,
4716 				    blob->id.sha1,
4717 				    a->worktree->base_commit_id->sha1, 1);
4718 				if (err)
4719 					goto done;
4720 			}
4721 			if (is_bad_symlink) {
4722 				got_fileindex_entry_filetype_set(ie,
4723 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
4724 			}
4725 		}
4726 		break;
4727 	}
4728 	default:
4729 		break;
4730 	}
4731 done:
4732 	free(ondisk_path);
4733 	free(path_content);
4734 	free(parent_path);
4735 	free(tree_path);
4736 	if (blob)
4737 		got_object_blob_close(blob);
4738 	if (tree)
4739 		got_object_tree_close(tree);
4740 	free(tree_id);
4741 	return err;
4742 }
4743 
4744 const struct got_error *
4745 got_worktree_revert(struct got_worktree *worktree,
4746     struct got_pathlist_head *paths,
4747     got_worktree_checkout_cb progress_cb, void *progress_arg,
4748     got_worktree_patch_cb patch_cb, void *patch_arg,
4749     struct got_repository *repo)
4750 {
4751 	struct got_fileindex *fileindex = NULL;
4752 	char *fileindex_path = NULL;
4753 	const struct got_error *err = NULL, *unlockerr = NULL;
4754 	const struct got_error *sync_err = NULL;
4755 	struct got_pathlist_entry *pe;
4756 	struct revert_file_args rfa;
4757 
4758 	err = lock_worktree(worktree, LOCK_EX);
4759 	if (err)
4760 		return err;
4761 
4762 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
4763 	if (err)
4764 		goto done;
4765 
4766 	rfa.worktree = worktree;
4767 	rfa.fileindex = fileindex;
4768 	rfa.progress_cb = progress_cb;
4769 	rfa.progress_arg = progress_arg;
4770 	rfa.patch_cb = patch_cb;
4771 	rfa.patch_arg = patch_arg;
4772 	rfa.repo = repo;
4773 	TAILQ_FOREACH(pe, paths, entry) {
4774 		err = worktree_status(worktree, pe->path, fileindex, repo,
4775 		    revert_file, &rfa, NULL, NULL, 0, 0);
4776 		if (err)
4777 			break;
4778 	}
4779 	sync_err = sync_fileindex(fileindex, fileindex_path);
4780 	if (sync_err && err == NULL)
4781 		err = sync_err;
4782 done:
4783 	free(fileindex_path);
4784 	if (fileindex)
4785 		got_fileindex_free(fileindex);
4786 	unlockerr = lock_worktree(worktree, LOCK_SH);
4787 	if (unlockerr && err == NULL)
4788 		err = unlockerr;
4789 	return err;
4790 }
4791 
4792 static void
4793 free_commitable(struct got_commitable *ct)
4794 {
4795 	free(ct->path);
4796 	free(ct->in_repo_path);
4797 	free(ct->ondisk_path);
4798 	free(ct->blob_id);
4799 	free(ct->base_blob_id);
4800 	free(ct->staged_blob_id);
4801 	free(ct->base_commit_id);
4802 	free(ct);
4803 }
4804 
4805 struct collect_commitables_arg {
4806 	struct got_pathlist_head *commitable_paths;
4807 	struct got_repository *repo;
4808 	struct got_worktree *worktree;
4809 	struct got_fileindex *fileindex;
4810 	int have_staged_files;
4811 	int allow_bad_symlinks;
4812 };
4813 
4814 static const struct got_error *
4815 collect_commitables(void *arg, unsigned char status,
4816     unsigned char staged_status, const char *relpath,
4817     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
4818     struct got_object_id *commit_id, int dirfd, const char *de_name)
4819 {
4820 	struct collect_commitables_arg *a = arg;
4821 	const struct got_error *err = NULL;
4822 	struct got_commitable *ct = NULL;
4823 	struct got_pathlist_entry *new = NULL;
4824 	char *parent_path = NULL, *path = NULL;
4825 	struct stat sb;
4826 
4827 	if (a->have_staged_files) {
4828 		if (staged_status != GOT_STATUS_MODIFY &&
4829 		    staged_status != GOT_STATUS_ADD &&
4830 		    staged_status != GOT_STATUS_DELETE)
4831 			return NULL;
4832 	} else {
4833 		if (status == GOT_STATUS_CONFLICT)
4834 			return got_error(GOT_ERR_COMMIT_CONFLICT);
4835 
4836 		if (status != GOT_STATUS_MODIFY &&
4837 		    status != GOT_STATUS_MODE_CHANGE &&
4838 		    status != GOT_STATUS_ADD &&
4839 		    status != GOT_STATUS_DELETE)
4840 			return NULL;
4841 	}
4842 
4843 	if (asprintf(&path, "/%s", relpath) == -1) {
4844 		err = got_error_from_errno("asprintf");
4845 		goto done;
4846 	}
4847 	if (strcmp(path, "/") == 0) {
4848 		parent_path = strdup("");
4849 		if (parent_path == NULL)
4850 			return got_error_from_errno("strdup");
4851 	} else {
4852 		err = got_path_dirname(&parent_path, path);
4853 		if (err)
4854 			return err;
4855 	}
4856 
4857 	ct = calloc(1, sizeof(*ct));
4858 	if (ct == NULL) {
4859 		err = got_error_from_errno("calloc");
4860 		goto done;
4861 	}
4862 
4863 	if (asprintf(&ct->ondisk_path, "%s/%s", a->worktree->root_path,
4864 	    relpath) == -1) {
4865 		err = got_error_from_errno("asprintf");
4866 		goto done;
4867 	}
4868 
4869 	if (staged_status == GOT_STATUS_ADD ||
4870 	    staged_status == GOT_STATUS_MODIFY) {
4871 		struct got_fileindex_entry *ie;
4872 		ie = got_fileindex_entry_get(a->fileindex, path, strlen(path));
4873 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
4874 		case GOT_FILEIDX_MODE_REGULAR_FILE:
4875 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
4876 			ct->mode = S_IFREG;
4877 			break;
4878 		case GOT_FILEIDX_MODE_SYMLINK:
4879 			ct->mode = S_IFLNK;
4880 			break;
4881 		default:
4882 			err = got_error_path(path, GOT_ERR_BAD_FILETYPE);
4883 			goto done;
4884 		}
4885 		ct->mode |= got_fileindex_entry_perms_get(ie);
4886 	} else if (status != GOT_STATUS_DELETE &&
4887 	    staged_status != GOT_STATUS_DELETE) {
4888 		if (dirfd != -1) {
4889 			if (fstatat(dirfd, de_name, &sb,
4890 			    AT_SYMLINK_NOFOLLOW) == -1) {
4891 				err = got_error_from_errno2("fstatat",
4892 				    ct->ondisk_path);
4893 				goto done;
4894 			}
4895 		} else if (lstat(ct->ondisk_path, &sb) == -1) {
4896 			err = got_error_from_errno2("lstat", ct->ondisk_path);
4897 			goto done;
4898 		}
4899 		ct->mode = sb.st_mode;
4900 	}
4901 
4902 	if (asprintf(&ct->in_repo_path, "%s%s%s", a->worktree->path_prefix,
4903 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
4904 	    relpath) == -1) {
4905 		err = got_error_from_errno("asprintf");
4906 		goto done;
4907 	}
4908 
4909 	if (S_ISLNK(ct->mode) && staged_status == GOT_STATUS_NO_CHANGE &&
4910 	    status == GOT_STATUS_ADD && !a->allow_bad_symlinks) {
4911 		int is_bad_symlink;
4912 		char target_path[PATH_MAX];
4913 		ssize_t target_len;
4914 		target_len = readlink(ct->ondisk_path, target_path,
4915 		    sizeof(target_path));
4916 		if (target_len == -1) {
4917 			err = got_error_from_errno2("readlink",
4918 			    ct->ondisk_path);
4919 			goto done;
4920 		}
4921 		err = is_bad_symlink_target(&is_bad_symlink, target_path,
4922 		    target_len, ct->ondisk_path, a->worktree->root_path);
4923 		if (err)
4924 			goto done;
4925 		if (is_bad_symlink) {
4926 			err = got_error_path(ct->ondisk_path,
4927 			    GOT_ERR_BAD_SYMLINK);
4928 			goto done;
4929 		}
4930 	}
4931 
4932 
4933 	ct->status = status;
4934 	ct->staged_status = staged_status;
4935 	ct->blob_id = NULL; /* will be filled in when blob gets created */
4936 	if (ct->status != GOT_STATUS_ADD &&
4937 	    ct->staged_status != GOT_STATUS_ADD) {
4938 		ct->base_blob_id = got_object_id_dup(blob_id);
4939 		if (ct->base_blob_id == NULL) {
4940 			err = got_error_from_errno("got_object_id_dup");
4941 			goto done;
4942 		}
4943 		ct->base_commit_id = got_object_id_dup(commit_id);
4944 		if (ct->base_commit_id == NULL) {
4945 			err = got_error_from_errno("got_object_id_dup");
4946 			goto done;
4947 		}
4948 	}
4949 	if (ct->staged_status == GOT_STATUS_ADD ||
4950 	    ct->staged_status == GOT_STATUS_MODIFY) {
4951 		ct->staged_blob_id = got_object_id_dup(staged_blob_id);
4952 		if (ct->staged_blob_id == NULL) {
4953 			err = got_error_from_errno("got_object_id_dup");
4954 			goto done;
4955 		}
4956 	}
4957 	ct->path = strdup(path);
4958 	if (ct->path == NULL) {
4959 		err = got_error_from_errno("strdup");
4960 		goto done;
4961 	}
4962 	err = got_pathlist_insert(&new, a->commitable_paths, ct->path, ct);
4963 done:
4964 	if (ct && (err || new == NULL))
4965 		free_commitable(ct);
4966 	free(parent_path);
4967 	free(path);
4968 	return err;
4969 }
4970 
4971 static const struct got_error *write_tree(struct got_object_id **, int *,
4972     struct got_tree_object *, const char *, struct got_pathlist_head *,
4973     got_worktree_status_cb status_cb, void *status_arg,
4974     struct got_repository *);
4975 
4976 static const struct got_error *
4977 write_subtree(struct got_object_id **new_subtree_id, int *nentries,
4978     struct got_tree_entry *te, const char *parent_path,
4979     struct got_pathlist_head *commitable_paths,
4980     got_worktree_status_cb status_cb, void *status_arg,
4981     struct got_repository *repo)
4982 {
4983 	const struct got_error *err = NULL;
4984 	struct got_tree_object *subtree;
4985 	char *subpath;
4986 
4987 	if (asprintf(&subpath, "%s%s%s", parent_path,
4988 	    got_path_is_root_dir(parent_path) ? "" : "/", te->name) == -1)
4989 		return got_error_from_errno("asprintf");
4990 
4991 	err = got_object_open_as_tree(&subtree, repo, &te->id);
4992 	if (err)
4993 		return err;
4994 
4995 	err = write_tree(new_subtree_id, nentries, subtree, subpath,
4996 	    commitable_paths, status_cb, status_arg, repo);
4997 	got_object_tree_close(subtree);
4998 	free(subpath);
4999 	return err;
5000 }
5001 
5002 static const struct got_error *
5003 match_ct_parent_path(int *match, struct got_commitable *ct, const char *path)
5004 {
5005 	const struct got_error *err = NULL;
5006 	char *ct_parent_path = NULL;
5007 
5008 	*match = 0;
5009 
5010 	if (strchr(ct->in_repo_path, '/') == NULL) {
5011 		*match = got_path_is_root_dir(path);
5012 		return NULL;
5013 	}
5014 
5015 	err = got_path_dirname(&ct_parent_path, ct->in_repo_path);
5016 	if (err)
5017 		return err;
5018 	*match = (strcmp(path, ct_parent_path) == 0);
5019 	free(ct_parent_path);
5020 	return err;
5021 }
5022 
5023 static mode_t
5024 get_ct_file_mode(struct got_commitable *ct)
5025 {
5026 	if (S_ISLNK(ct->mode))
5027 		return S_IFLNK;
5028 
5029 	return S_IFREG | (ct->mode & ((S_IRWXU | S_IRWXG | S_IRWXO)));
5030 }
5031 
5032 static const struct got_error *
5033 alloc_modified_blob_tree_entry(struct got_tree_entry **new_te,
5034     struct got_tree_entry *te, struct got_commitable *ct)
5035 {
5036 	const struct got_error *err = NULL;
5037 
5038 	*new_te = NULL;
5039 
5040 	err = got_object_tree_entry_dup(new_te, te);
5041 	if (err)
5042 		goto done;
5043 
5044 	(*new_te)->mode = get_ct_file_mode(ct);
5045 
5046 	if (ct->staged_status == GOT_STATUS_MODIFY)
5047 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5048 		    sizeof((*new_te)->id));
5049 	else
5050 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5051 done:
5052 	if (err && *new_te) {
5053 		free(*new_te);
5054 		*new_te = NULL;
5055 	}
5056 	return err;
5057 }
5058 
5059 static const struct got_error *
5060 alloc_added_blob_tree_entry(struct got_tree_entry **new_te,
5061     struct got_commitable *ct)
5062 {
5063 	const struct got_error *err = NULL;
5064 	char *ct_name = NULL;
5065 
5066 	 *new_te = NULL;
5067 
5068 	*new_te = calloc(1, sizeof(**new_te));
5069 	if (*new_te == NULL)
5070 		return got_error_from_errno("calloc");
5071 
5072 	err = got_path_basename(&ct_name, ct->path);
5073 	if (err)
5074 		goto done;
5075 	if (strlcpy((*new_te)->name, ct_name, sizeof((*new_te)->name)) >=
5076 	    sizeof((*new_te)->name)) {
5077 		err = got_error(GOT_ERR_NO_SPACE);
5078 		goto done;
5079 	}
5080 
5081 	(*new_te)->mode = get_ct_file_mode(ct);
5082 
5083 	if (ct->staged_status == GOT_STATUS_ADD)
5084 		memcpy(&(*new_te)->id, ct->staged_blob_id,
5085 		    sizeof((*new_te)->id));
5086 	else
5087 		memcpy(&(*new_te)->id, ct->blob_id, sizeof((*new_te)->id));
5088 done:
5089 	free(ct_name);
5090 	if (err && *new_te) {
5091 		free(*new_te);
5092 		*new_te = NULL;
5093 	}
5094 	return err;
5095 }
5096 
5097 static const struct got_error *
5098 insert_tree_entry(struct got_tree_entry *new_te,
5099     struct got_pathlist_head *paths)
5100 {
5101 	const struct got_error *err = NULL;
5102 	struct got_pathlist_entry *new_pe;
5103 
5104 	err = got_pathlist_insert(&new_pe, paths, new_te->name, new_te);
5105 	if (err)
5106 		return err;
5107 	if (new_pe == NULL)
5108 		return got_error(GOT_ERR_TREE_DUP_ENTRY);
5109 	return NULL;
5110 }
5111 
5112 static const struct got_error *
5113 report_ct_status(struct got_commitable *ct,
5114     got_worktree_status_cb status_cb, void *status_arg)
5115 {
5116 	const char *ct_path = ct->path;
5117 	unsigned char status;
5118 
5119 	while (ct_path[0] == '/')
5120 		ct_path++;
5121 
5122 	if (ct->staged_status != GOT_STATUS_NO_CHANGE)
5123 		status = ct->staged_status;
5124 	else
5125 		status = ct->status;
5126 
5127 	return (*status_cb)(status_arg, status, GOT_STATUS_NO_CHANGE,
5128 	    ct_path, ct->blob_id, NULL, NULL, -1, NULL);
5129 }
5130 
5131 static const struct got_error *
5132 match_modified_subtree(int *modified, struct got_tree_entry *te,
5133     const char *base_tree_path, struct got_pathlist_head *commitable_paths)
5134 {
5135 	const struct got_error *err = NULL;
5136 	struct got_pathlist_entry *pe;
5137 	char *te_path;
5138 
5139 	*modified = 0;
5140 
5141 	if (asprintf(&te_path, "%s%s%s", base_tree_path,
5142 	    got_path_is_root_dir(base_tree_path) ? "" : "/",
5143 	    te->name) == -1)
5144 		return got_error_from_errno("asprintf");
5145 
5146 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5147 		struct got_commitable *ct = pe->data;
5148 		*modified = got_path_is_child(ct->in_repo_path, te_path,
5149 		    strlen(te_path));
5150 		if (*modified)
5151 			break;
5152 	}
5153 
5154 	free(te_path);
5155 	return err;
5156 }
5157 
5158 static const struct got_error *
5159 match_deleted_or_modified_ct(struct got_commitable **ctp,
5160     struct got_tree_entry *te, const char *base_tree_path,
5161     struct got_pathlist_head *commitable_paths)
5162 {
5163 	const struct got_error *err = NULL;
5164 	struct got_pathlist_entry *pe;
5165 
5166 	*ctp = NULL;
5167 
5168 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5169 		struct got_commitable *ct = pe->data;
5170 		char *ct_name = NULL;
5171 		int path_matches;
5172 
5173 		if (ct->staged_status == GOT_STATUS_NO_CHANGE) {
5174 			if (ct->status != GOT_STATUS_MODIFY &&
5175 			    ct->status != GOT_STATUS_MODE_CHANGE &&
5176 			    ct->status != GOT_STATUS_DELETE)
5177 				continue;
5178 		} else {
5179 			if (ct->staged_status != GOT_STATUS_MODIFY &&
5180 			    ct->staged_status != GOT_STATUS_DELETE)
5181 				continue;
5182 		}
5183 
5184 		if (got_object_id_cmp(ct->base_blob_id, &te->id) != 0)
5185 			continue;
5186 
5187 		err = match_ct_parent_path(&path_matches, ct, base_tree_path);
5188 		if (err)
5189 			return err;
5190 		if (!path_matches)
5191 			continue;
5192 
5193 		err = got_path_basename(&ct_name, pe->path);
5194 		if (err)
5195 			return err;
5196 
5197 		if (strcmp(te->name, ct_name) != 0) {
5198 			free(ct_name);
5199 			continue;
5200 		}
5201 		free(ct_name);
5202 
5203 		*ctp = ct;
5204 		break;
5205 	}
5206 
5207 	return err;
5208 }
5209 
5210 static const struct got_error *
5211 make_subtree_for_added_blob(struct got_tree_entry **new_tep,
5212     const char *child_path, const char *path_base_tree,
5213     struct got_pathlist_head *commitable_paths,
5214     got_worktree_status_cb status_cb, void *status_arg,
5215     struct got_repository *repo)
5216 {
5217 	const struct got_error *err = NULL;
5218 	struct got_tree_entry *new_te;
5219 	char *subtree_path;
5220 	struct got_object_id *id = NULL;
5221 	int nentries;
5222 
5223 	*new_tep = NULL;
5224 
5225 	if (asprintf(&subtree_path, "%s%s%s", path_base_tree,
5226 	    got_path_is_root_dir(path_base_tree) ? "" : "/",
5227 	    child_path) == -1)
5228 		return got_error_from_errno("asprintf");
5229 
5230 	new_te = calloc(1, sizeof(*new_te));
5231 	if (new_te == NULL)
5232 		return got_error_from_errno("calloc");
5233 	new_te->mode = S_IFDIR;
5234 
5235 	if (strlcpy(new_te->name, child_path, sizeof(new_te->name)) >=
5236 	    sizeof(new_te->name)) {
5237 		err = got_error(GOT_ERR_NO_SPACE);
5238 		goto done;
5239 	}
5240 	err = write_tree(&id, &nentries, NULL, subtree_path,
5241 	    commitable_paths, status_cb, status_arg, repo);
5242 	if (err) {
5243 		free(new_te);
5244 		goto done;
5245 	}
5246 	memcpy(&new_te->id, id, sizeof(new_te->id));
5247 done:
5248 	free(id);
5249 	free(subtree_path);
5250 	if (err == NULL)
5251 		*new_tep = new_te;
5252 	return err;
5253 }
5254 
5255 static const struct got_error *
5256 write_tree(struct got_object_id **new_tree_id, int *nentries,
5257     struct got_tree_object *base_tree, const char *path_base_tree,
5258     struct got_pathlist_head *commitable_paths,
5259     got_worktree_status_cb status_cb, void *status_arg,
5260     struct got_repository *repo)
5261 {
5262 	const struct got_error *err = NULL;
5263 	struct got_pathlist_head paths;
5264 	struct got_tree_entry *te, *new_te = NULL;
5265 	struct got_pathlist_entry *pe;
5266 
5267 	TAILQ_INIT(&paths);
5268 	*nentries = 0;
5269 
5270 	/* Insert, and recurse into, newly added entries first. */
5271 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5272 		struct got_commitable *ct = pe->data;
5273 		char *child_path = NULL, *slash;
5274 
5275 		if ((ct->status != GOT_STATUS_ADD &&
5276 		    ct->staged_status != GOT_STATUS_ADD) ||
5277 		    (ct->flags & GOT_COMMITABLE_ADDED))
5278 			continue;
5279 
5280 		if (!got_path_is_child(ct->in_repo_path, path_base_tree,
5281 		    strlen(path_base_tree)))
5282 			continue;
5283 
5284 		err = got_path_skip_common_ancestor(&child_path, path_base_tree,
5285 		    ct->in_repo_path);
5286 		if (err)
5287 			goto done;
5288 
5289 		slash = strchr(child_path, '/');
5290 		if (slash == NULL) {
5291 			err = alloc_added_blob_tree_entry(&new_te, ct);
5292 			if (err)
5293 				goto done;
5294 			err = report_ct_status(ct, status_cb, status_arg);
5295 			if (err)
5296 				goto done;
5297 			ct->flags |= GOT_COMMITABLE_ADDED;
5298 			err = insert_tree_entry(new_te, &paths);
5299 			if (err)
5300 				goto done;
5301 			(*nentries)++;
5302 		} else {
5303 			*slash = '\0'; /* trim trailing path components */
5304 			if (base_tree == NULL ||
5305 			    got_object_tree_find_entry(base_tree, child_path)
5306 			    == NULL) {
5307 				err = make_subtree_for_added_blob(&new_te,
5308 				    child_path, path_base_tree,
5309 				    commitable_paths, status_cb, status_arg,
5310 				    repo);
5311 				if (err)
5312 					goto done;
5313 				err = insert_tree_entry(new_te, &paths);
5314 				if (err)
5315 					goto done;
5316 				(*nentries)++;
5317 			}
5318 		}
5319 	}
5320 
5321 	if (base_tree) {
5322 		int i, nbase_entries;
5323 		/* Handle modified and deleted entries. */
5324 		nbase_entries = got_object_tree_get_nentries(base_tree);
5325 		for (i = 0; i < nbase_entries; i++) {
5326 			struct got_commitable *ct = NULL;
5327 
5328 			te = got_object_tree_get_entry(base_tree, i);
5329 			if (got_object_tree_entry_is_submodule(te)) {
5330 				/* Entry is a submodule; just copy it. */
5331 				err = got_object_tree_entry_dup(&new_te, te);
5332 				if (err)
5333 					goto done;
5334 				err = insert_tree_entry(new_te, &paths);
5335 				if (err)
5336 					goto done;
5337 				(*nentries)++;
5338 				continue;
5339 			}
5340 
5341 			if (S_ISDIR(te->mode)) {
5342 				int modified;
5343 				err = got_object_tree_entry_dup(&new_te, te);
5344 				if (err)
5345 					goto done;
5346 				err = match_modified_subtree(&modified, te,
5347 				    path_base_tree, commitable_paths);
5348 				if (err)
5349 					goto done;
5350 				/* Avoid recursion into unmodified subtrees. */
5351 				if (modified) {
5352 					struct got_object_id *new_id;
5353 					int nsubentries;
5354 					err = write_subtree(&new_id,
5355 					    &nsubentries, te,
5356 					    path_base_tree, commitable_paths,
5357 					    status_cb, status_arg, repo);
5358 					if (err)
5359 						goto done;
5360 					if (nsubentries == 0) {
5361 						/* All entries were deleted. */
5362 						free(new_id);
5363 						continue;
5364 					}
5365 					memcpy(&new_te->id, new_id,
5366 					    sizeof(new_te->id));
5367 					free(new_id);
5368 				}
5369 				err = insert_tree_entry(new_te, &paths);
5370 				if (err)
5371 					goto done;
5372 				(*nentries)++;
5373 				continue;
5374 			}
5375 
5376 			err = match_deleted_or_modified_ct(&ct, te,
5377 			    path_base_tree, commitable_paths);
5378 			if (err)
5379 				goto done;
5380 			if (ct) {
5381 				/* NB: Deleted entries get dropped here. */
5382 				if (ct->status == GOT_STATUS_MODIFY ||
5383 				    ct->status == GOT_STATUS_MODE_CHANGE ||
5384 				    ct->staged_status == GOT_STATUS_MODIFY) {
5385 					err = alloc_modified_blob_tree_entry(
5386 					    &new_te, te, ct);
5387 					if (err)
5388 						goto done;
5389 					err = insert_tree_entry(new_te, &paths);
5390 					if (err)
5391 						goto done;
5392 					(*nentries)++;
5393 				}
5394 				err = report_ct_status(ct, status_cb,
5395 				    status_arg);
5396 				if (err)
5397 					goto done;
5398 			} else {
5399 				/* Entry is unchanged; just copy it. */
5400 				err = got_object_tree_entry_dup(&new_te, te);
5401 				if (err)
5402 					goto done;
5403 				err = insert_tree_entry(new_te, &paths);
5404 				if (err)
5405 					goto done;
5406 				(*nentries)++;
5407 			}
5408 		}
5409 	}
5410 
5411 	/* Write new list of entries; deleted entries have been dropped. */
5412 	err = got_object_tree_create(new_tree_id, &paths, *nentries, repo);
5413 done:
5414 	got_pathlist_free(&paths);
5415 	return err;
5416 }
5417 
5418 static const struct got_error *
5419 update_fileindex_after_commit(struct got_worktree *worktree,
5420     struct got_pathlist_head *commitable_paths,
5421     struct got_object_id *new_base_commit_id,
5422     struct got_fileindex *fileindex, int have_staged_files)
5423 {
5424 	const struct got_error *err = NULL;
5425 	struct got_pathlist_entry *pe;
5426 	char *relpath = NULL;
5427 
5428 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5429 		struct got_fileindex_entry *ie;
5430 		struct got_commitable *ct = pe->data;
5431 
5432 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
5433 
5434 		err = got_path_skip_common_ancestor(&relpath,
5435 		    worktree->root_path, ct->ondisk_path);
5436 		if (err)
5437 			goto done;
5438 
5439 		if (ie) {
5440 			if (ct->status == GOT_STATUS_DELETE ||
5441 			    ct->staged_status == GOT_STATUS_DELETE) {
5442 				got_fileindex_entry_remove(fileindex, ie);
5443 			} else if (ct->staged_status == GOT_STATUS_ADD ||
5444 			    ct->staged_status == GOT_STATUS_MODIFY) {
5445 				got_fileindex_entry_stage_set(ie,
5446 				    GOT_FILEIDX_STAGE_NONE);
5447 				got_fileindex_entry_staged_filetype_set(ie, 0);
5448 
5449 				err = got_fileindex_entry_update(ie,
5450 				    worktree->root_fd, relpath,
5451 				    ct->staged_blob_id->sha1,
5452 				    new_base_commit_id->sha1,
5453 				    !have_staged_files);
5454 			} else
5455 				err = got_fileindex_entry_update(ie,
5456 				    worktree->root_fd, relpath,
5457 				    ct->blob_id->sha1,
5458 				    new_base_commit_id->sha1,
5459 				    !have_staged_files);
5460 		} else {
5461 			err = got_fileindex_entry_alloc(&ie, pe->path);
5462 			if (err)
5463 				goto done;
5464 			err = got_fileindex_entry_update(ie,
5465 			    worktree->root_fd, relpath, ct->blob_id->sha1,
5466 			    new_base_commit_id->sha1, 1);
5467 			if (err) {
5468 				got_fileindex_entry_free(ie);
5469 				goto done;
5470 			}
5471 			err = got_fileindex_entry_add(fileindex, ie);
5472 			if (err) {
5473 				got_fileindex_entry_free(ie);
5474 				goto done;
5475 			}
5476 		}
5477 		free(relpath);
5478 		relpath = NULL;
5479 	}
5480 done:
5481 	free(relpath);
5482 	return err;
5483 }
5484 
5485 
5486 static const struct got_error *
5487 check_out_of_date(const char *in_repo_path, unsigned char status,
5488     unsigned char staged_status, struct got_object_id *base_blob_id,
5489     struct got_object_id *base_commit_id,
5490     struct got_object_id *head_commit_id, struct got_repository *repo,
5491     int ood_errcode)
5492 {
5493 	const struct got_error *err = NULL;
5494 	struct got_object_id *id = NULL;
5495 
5496 	if (status != GOT_STATUS_ADD && staged_status != GOT_STATUS_ADD) {
5497 		/* Trivial case: base commit == head commit */
5498 		if (got_object_id_cmp(base_commit_id, head_commit_id) == 0)
5499 			return NULL;
5500 		/*
5501 		 * Ensure file content which local changes were based
5502 		 * on matches file content in the branch head.
5503 		 */
5504 		err = got_object_id_by_path(&id, repo, head_commit_id,
5505 		    in_repo_path);
5506 		if (err) {
5507 			if (err->code == GOT_ERR_NO_TREE_ENTRY)
5508 				err = got_error(ood_errcode);
5509 			goto done;
5510 		} else if (got_object_id_cmp(id, base_blob_id) != 0)
5511 			err = got_error(ood_errcode);
5512 	} else {
5513 		/* Require that added files don't exist in the branch head. */
5514 		err = got_object_id_by_path(&id, repo, head_commit_id,
5515 		    in_repo_path);
5516 		if (err && err->code != GOT_ERR_NO_TREE_ENTRY)
5517 			goto done;
5518 		err = id ? got_error(ood_errcode) : NULL;
5519 	}
5520 done:
5521 	free(id);
5522 	return err;
5523 }
5524 
5525 const struct got_error *
5526 commit_worktree(struct got_object_id **new_commit_id,
5527     struct got_pathlist_head *commitable_paths,
5528     struct got_object_id *head_commit_id, struct got_worktree *worktree,
5529     const char *author, const char *committer,
5530     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
5531     got_worktree_status_cb status_cb, void *status_arg,
5532     struct got_repository *repo)
5533 {
5534 	const struct got_error *err = NULL, *unlockerr = NULL;
5535 	struct got_pathlist_entry *pe;
5536 	const char *head_ref_name = NULL;
5537 	struct got_commit_object *head_commit = NULL;
5538 	struct got_reference *head_ref2 = NULL;
5539 	struct got_object_id *head_commit_id2 = NULL;
5540 	struct got_tree_object *head_tree = NULL;
5541 	struct got_object_id *new_tree_id = NULL;
5542 	int nentries;
5543 	struct got_object_id_queue parent_ids;
5544 	struct got_object_qid *pid = NULL;
5545 	char *logmsg = NULL;
5546 
5547 	*new_commit_id = NULL;
5548 
5549 	SIMPLEQ_INIT(&parent_ids);
5550 
5551 	err = got_object_open_as_commit(&head_commit, repo, head_commit_id);
5552 	if (err)
5553 		goto done;
5554 
5555 	err = got_object_open_as_tree(&head_tree, repo, head_commit->tree_id);
5556 	if (err)
5557 		goto done;
5558 
5559 	if (commit_msg_cb != NULL) {
5560 		err = commit_msg_cb(commitable_paths, &logmsg, commit_arg);
5561 		if (err)
5562 			goto done;
5563 	}
5564 
5565 	if (logmsg == NULL || strlen(logmsg) == 0) {
5566 		err = got_error(GOT_ERR_COMMIT_MSG_EMPTY);
5567 		goto done;
5568 	}
5569 
5570 	/* Create blobs from added and modified files and record their IDs. */
5571 	TAILQ_FOREACH(pe, commitable_paths, entry) {
5572 		struct got_commitable *ct = pe->data;
5573 		char *ondisk_path;
5574 
5575 		/* Blobs for staged files already exist. */
5576 		if (ct->staged_status == GOT_STATUS_ADD ||
5577 		    ct->staged_status == GOT_STATUS_MODIFY)
5578 			continue;
5579 
5580 		if (ct->status != GOT_STATUS_ADD &&
5581 		    ct->status != GOT_STATUS_MODIFY &&
5582 		    ct->status != GOT_STATUS_MODE_CHANGE)
5583 			continue;
5584 
5585 		if (asprintf(&ondisk_path, "%s/%s",
5586 		    worktree->root_path, pe->path) == -1) {
5587 			err = got_error_from_errno("asprintf");
5588 			goto done;
5589 		}
5590 		err = got_object_blob_create(&ct->blob_id, ondisk_path, repo);
5591 		free(ondisk_path);
5592 		if (err)
5593 			goto done;
5594 	}
5595 
5596 	/* Recursively write new tree objects. */
5597 	err = write_tree(&new_tree_id, &nentries, head_tree, "/",
5598 	    commitable_paths, status_cb, status_arg, repo);
5599 	if (err)
5600 		goto done;
5601 
5602 	err = got_object_qid_alloc(&pid, worktree->base_commit_id);
5603 	if (err)
5604 		goto done;
5605 	SIMPLEQ_INSERT_TAIL(&parent_ids, pid, entry);
5606 	err = got_object_commit_create(new_commit_id, new_tree_id, &parent_ids,
5607 	    1, author, time(NULL), committer, time(NULL), logmsg, repo);
5608 	got_object_qid_free(pid);
5609 	if (logmsg != NULL)
5610 		free(logmsg);
5611 	if (err)
5612 		goto done;
5613 
5614 	/* Check if a concurrent commit to our branch has occurred. */
5615 	head_ref_name = got_worktree_get_head_ref_name(worktree);
5616 	if (head_ref_name == NULL) {
5617 		err = got_error_from_errno("got_worktree_get_head_ref_name");
5618 		goto done;
5619 	}
5620 	/* Lock the reference here to prevent concurrent modification. */
5621 	err = got_ref_open(&head_ref2, repo, head_ref_name, 1);
5622 	if (err)
5623 		goto done;
5624 	err = got_ref_resolve(&head_commit_id2, repo, head_ref2);
5625 	if (err)
5626 		goto done;
5627 	if (got_object_id_cmp(head_commit_id, head_commit_id2) != 0) {
5628 		err = got_error(GOT_ERR_COMMIT_HEAD_CHANGED);
5629 		goto done;
5630 	}
5631 	/* Update branch head in repository. */
5632 	err = got_ref_change_ref(head_ref2, *new_commit_id);
5633 	if (err)
5634 		goto done;
5635 	err = got_ref_write(head_ref2, repo);
5636 	if (err)
5637 		goto done;
5638 
5639 	err = got_worktree_set_base_commit_id(worktree, repo, *new_commit_id);
5640 	if (err)
5641 		goto done;
5642 
5643 	err = ref_base_commit(worktree, repo);
5644 	if (err)
5645 		goto done;
5646 done:
5647 	if (head_tree)
5648 		got_object_tree_close(head_tree);
5649 	if (head_commit)
5650 		got_object_commit_close(head_commit);
5651 	free(head_commit_id2);
5652 	if (head_ref2) {
5653 		unlockerr = got_ref_unlock(head_ref2);
5654 		if (unlockerr && err == NULL)
5655 			err = unlockerr;
5656 		got_ref_close(head_ref2);
5657 	}
5658 	return err;
5659 }
5660 
5661 static const struct got_error *
5662 check_path_is_commitable(const char *path,
5663     struct got_pathlist_head *commitable_paths)
5664 {
5665 	struct got_pathlist_entry *cpe = NULL;
5666 	size_t path_len = strlen(path);
5667 
5668 	TAILQ_FOREACH(cpe, commitable_paths, entry) {
5669 		struct got_commitable *ct = cpe->data;
5670 		const char *ct_path = ct->path;
5671 
5672 		while (ct_path[0] == '/')
5673 			ct_path++;
5674 
5675 		if (strcmp(path, ct_path) == 0 ||
5676 		    got_path_is_child(ct_path, path, path_len))
5677 			break;
5678 	}
5679 
5680 	if (cpe == NULL)
5681 		return got_error_path(path, GOT_ERR_BAD_PATH);
5682 
5683 	return NULL;
5684 }
5685 
5686 static const struct got_error *
5687 check_staged_file(void *arg, struct got_fileindex_entry *ie)
5688 {
5689 	int *have_staged_files = arg;
5690 
5691 	if (got_fileindex_entry_stage_get(ie) != GOT_FILEIDX_STAGE_NONE) {
5692 		*have_staged_files = 1;
5693 		return got_error(GOT_ERR_CANCELLED);
5694 	}
5695 
5696 	return NULL;
5697 }
5698 
5699 static const struct got_error *
5700 check_non_staged_files(struct got_fileindex *fileindex,
5701     struct got_pathlist_head *paths)
5702 {
5703 	struct got_pathlist_entry *pe;
5704 	struct got_fileindex_entry *ie;
5705 
5706 	TAILQ_FOREACH(pe, paths, entry) {
5707 		if (pe->path[0] == '\0')
5708 			continue;
5709 		ie = got_fileindex_entry_get(fileindex, pe->path, pe->path_len);
5710 		if (ie == NULL)
5711 			return got_error_path(pe->path, GOT_ERR_BAD_PATH);
5712 		if (got_fileindex_entry_stage_get(ie) == GOT_FILEIDX_STAGE_NONE)
5713 			return got_error_path(pe->path,
5714 			    GOT_ERR_FILE_NOT_STAGED);
5715 	}
5716 
5717 	return NULL;
5718 }
5719 
5720 const struct got_error *
5721 got_worktree_commit(struct got_object_id **new_commit_id,
5722     struct got_worktree *worktree, struct got_pathlist_head *paths,
5723     const char *author, const char *committer, int allow_bad_symlinks,
5724     got_worktree_commit_msg_cb commit_msg_cb, void *commit_arg,
5725     got_worktree_status_cb status_cb, void *status_arg,
5726     struct got_repository *repo)
5727 {
5728 	const struct got_error *err = NULL, *unlockerr = NULL, *sync_err;
5729 	struct got_fileindex *fileindex = NULL;
5730 	char *fileindex_path = NULL;
5731 	struct got_pathlist_head commitable_paths;
5732 	struct collect_commitables_arg cc_arg;
5733 	struct got_pathlist_entry *pe;
5734 	struct got_reference *head_ref = NULL;
5735 	struct got_object_id *head_commit_id = NULL;
5736 	int have_staged_files = 0;
5737 
5738 	*new_commit_id = NULL;
5739 
5740 	TAILQ_INIT(&commitable_paths);
5741 
5742 	err = lock_worktree(worktree, LOCK_EX);
5743 	if (err)
5744 		goto done;
5745 
5746 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
5747 	if (err)
5748 		goto done;
5749 
5750 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
5751 	if (err)
5752 		goto done;
5753 
5754 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
5755 	if (err)
5756 		goto done;
5757 
5758 	err = got_fileindex_for_each_entry_safe(fileindex, check_staged_file,
5759 	    &have_staged_files);
5760 	if (err && err->code != GOT_ERR_CANCELLED)
5761 		goto done;
5762 	if (have_staged_files) {
5763 		err = check_non_staged_files(fileindex, paths);
5764 		if (err)
5765 			goto done;
5766 	}
5767 
5768 	cc_arg.commitable_paths = &commitable_paths;
5769 	cc_arg.worktree = worktree;
5770 	cc_arg.fileindex = fileindex;
5771 	cc_arg.repo = repo;
5772 	cc_arg.have_staged_files = have_staged_files;
5773 	cc_arg.allow_bad_symlinks = allow_bad_symlinks;
5774 	TAILQ_FOREACH(pe, paths, entry) {
5775 		err = worktree_status(worktree, pe->path, fileindex, repo,
5776 		    collect_commitables, &cc_arg, NULL, NULL, 0, 0);
5777 		if (err)
5778 			goto done;
5779 	}
5780 
5781 	if (TAILQ_EMPTY(&commitable_paths)) {
5782 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
5783 		goto done;
5784 	}
5785 
5786 	TAILQ_FOREACH(pe, paths, entry) {
5787 		err = check_path_is_commitable(pe->path, &commitable_paths);
5788 		if (err)
5789 			goto done;
5790 	}
5791 
5792 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
5793 		struct got_commitable *ct = pe->data;
5794 		const char *ct_path = ct->in_repo_path;
5795 
5796 		while (ct_path[0] == '/')
5797 			ct_path++;
5798 		err = check_out_of_date(ct_path, ct->status,
5799 		    ct->staged_status, ct->base_blob_id, ct->base_commit_id,
5800 		    head_commit_id, repo, GOT_ERR_COMMIT_OUT_OF_DATE);
5801 		if (err)
5802 			goto done;
5803 
5804 	}
5805 
5806 	err = commit_worktree(new_commit_id, &commitable_paths,
5807 	    head_commit_id, worktree, author, committer,
5808 	    commit_msg_cb, commit_arg, status_cb, status_arg, repo);
5809 	if (err)
5810 		goto done;
5811 
5812 	err = update_fileindex_after_commit(worktree, &commitable_paths,
5813 	    *new_commit_id, fileindex, have_staged_files);
5814 	sync_err = sync_fileindex(fileindex, fileindex_path);
5815 	if (sync_err && err == NULL)
5816 		err = sync_err;
5817 done:
5818 	if (fileindex)
5819 		got_fileindex_free(fileindex);
5820 	free(fileindex_path);
5821 	unlockerr = lock_worktree(worktree, LOCK_SH);
5822 	if (unlockerr && err == NULL)
5823 		err = unlockerr;
5824 	TAILQ_FOREACH(pe, &commitable_paths, entry) {
5825 		struct got_commitable *ct = pe->data;
5826 		free_commitable(ct);
5827 	}
5828 	got_pathlist_free(&commitable_paths);
5829 	return err;
5830 }
5831 
5832 const char *
5833 got_commitable_get_path(struct got_commitable *ct)
5834 {
5835 	return ct->path;
5836 }
5837 
5838 unsigned int
5839 got_commitable_get_status(struct got_commitable *ct)
5840 {
5841 	return ct->status;
5842 }
5843 
5844 struct check_rebase_ok_arg {
5845 	struct got_worktree *worktree;
5846 	struct got_repository *repo;
5847 };
5848 
5849 static const struct got_error *
5850 check_rebase_ok(void *arg, struct got_fileindex_entry *ie)
5851 {
5852 	const struct got_error *err = NULL;
5853 	struct check_rebase_ok_arg *a = arg;
5854 	unsigned char status;
5855 	struct stat sb;
5856 	char *ondisk_path;
5857 
5858 	/* Reject rebase of a work tree with mixed base commits. */
5859 	if (memcmp(ie->commit_sha1, a->worktree->base_commit_id->sha1,
5860 	    SHA1_DIGEST_LENGTH))
5861 		return got_error(GOT_ERR_MIXED_COMMITS);
5862 
5863 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, ie->path)
5864 	    == -1)
5865 		return got_error_from_errno("asprintf");
5866 
5867 	/* Reject rebase of a work tree with modified or staged files. */
5868 	err = get_file_status(&status, &sb, ie, ondisk_path, -1, NULL, a->repo);
5869 	free(ondisk_path);
5870 	if (err)
5871 		return err;
5872 
5873 	if (status != GOT_STATUS_NO_CHANGE)
5874 		return got_error(GOT_ERR_MODIFIED);
5875 	if (get_staged_status(ie) != GOT_STATUS_NO_CHANGE)
5876 		return got_error_path(ie->path, GOT_ERR_FILE_STAGED);
5877 
5878 	return NULL;
5879 }
5880 
5881 const struct got_error *
5882 got_worktree_rebase_prepare(struct got_reference **new_base_branch_ref,
5883     struct got_reference **tmp_branch, struct got_fileindex **fileindex,
5884     struct got_worktree *worktree, struct got_reference *branch,
5885     struct got_repository *repo)
5886 {
5887 	const struct got_error *err = NULL;
5888 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
5889 	char *branch_ref_name = NULL;
5890 	char *fileindex_path = NULL;
5891 	struct check_rebase_ok_arg ok_arg;
5892 	struct got_reference *wt_branch = NULL, *branch_ref = NULL;
5893 	struct got_object_id *wt_branch_tip = NULL;
5894 
5895 	*new_base_branch_ref = NULL;
5896 	*tmp_branch = NULL;
5897 	*fileindex = NULL;
5898 
5899 	err = lock_worktree(worktree, LOCK_EX);
5900 	if (err)
5901 		return err;
5902 
5903 	err = open_fileindex(fileindex, &fileindex_path, worktree);
5904 	if (err)
5905 		goto done;
5906 
5907 	ok_arg.worktree = worktree;
5908 	ok_arg.repo = repo;
5909 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
5910 	    &ok_arg);
5911 	if (err)
5912 		goto done;
5913 
5914 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
5915 	if (err)
5916 		goto done;
5917 
5918 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
5919 	if (err)
5920 		goto done;
5921 
5922 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
5923 	if (err)
5924 		goto done;
5925 
5926 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
5927 	    0);
5928 	if (err)
5929 		goto done;
5930 
5931 	err = got_ref_resolve(&wt_branch_tip, repo, wt_branch);
5932 	if (err)
5933 		goto done;
5934 	if (got_object_id_cmp(worktree->base_commit_id, wt_branch_tip) != 0) {
5935 		err = got_error(GOT_ERR_REBASE_OUT_OF_DATE);
5936 		goto done;
5937 	}
5938 
5939 	err = got_ref_alloc_symref(new_base_branch_ref,
5940 	    new_base_branch_ref_name, wt_branch);
5941 	if (err)
5942 		goto done;
5943 	err = got_ref_write(*new_base_branch_ref, repo);
5944 	if (err)
5945 		goto done;
5946 
5947 	/* TODO Lock original branch's ref while rebasing? */
5948 
5949 	err = got_ref_alloc_symref(&branch_ref, branch_ref_name, branch);
5950 	if (err)
5951 		goto done;
5952 
5953 	err = got_ref_write(branch_ref, repo);
5954 	if (err)
5955 		goto done;
5956 
5957 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
5958 	    worktree->base_commit_id);
5959 	if (err)
5960 		goto done;
5961 	err = got_ref_write(*tmp_branch, repo);
5962 	if (err)
5963 		goto done;
5964 
5965 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
5966 	if (err)
5967 		goto done;
5968 done:
5969 	free(fileindex_path);
5970 	free(tmp_branch_name);
5971 	free(new_base_branch_ref_name);
5972 	free(branch_ref_name);
5973 	if (branch_ref)
5974 		got_ref_close(branch_ref);
5975 	if (wt_branch)
5976 		got_ref_close(wt_branch);
5977 	free(wt_branch_tip);
5978 	if (err) {
5979 		if (*new_base_branch_ref) {
5980 			got_ref_close(*new_base_branch_ref);
5981 			*new_base_branch_ref = NULL;
5982 		}
5983 		if (*tmp_branch) {
5984 			got_ref_close(*tmp_branch);
5985 			*tmp_branch = NULL;
5986 		}
5987 		if (*fileindex) {
5988 			got_fileindex_free(*fileindex);
5989 			*fileindex = NULL;
5990 		}
5991 		lock_worktree(worktree, LOCK_SH);
5992 	}
5993 	return err;
5994 }
5995 
5996 const struct got_error *
5997 got_worktree_rebase_continue(struct got_object_id **commit_id,
5998     struct got_reference **new_base_branch, struct got_reference **tmp_branch,
5999     struct got_reference **branch, struct got_fileindex **fileindex,
6000     struct got_worktree *worktree, struct got_repository *repo)
6001 {
6002 	const struct got_error *err;
6003 	char *commit_ref_name = NULL, *new_base_branch_ref_name = NULL;
6004 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
6005 	struct got_reference *commit_ref = NULL, *branch_ref = NULL;
6006 	char *fileindex_path = NULL;
6007 	int have_staged_files = 0;
6008 
6009 	*commit_id = NULL;
6010 	*new_base_branch = NULL;
6011 	*tmp_branch = NULL;
6012 	*branch = NULL;
6013 	*fileindex = NULL;
6014 
6015 	err = lock_worktree(worktree, LOCK_EX);
6016 	if (err)
6017 		return err;
6018 
6019 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6020 	if (err)
6021 		goto done;
6022 
6023 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
6024 	    &have_staged_files);
6025 	if (err && err->code != GOT_ERR_CANCELLED)
6026 		goto done;
6027 	if (have_staged_files) {
6028 		err = got_error(GOT_ERR_STAGED_PATHS);
6029 		goto done;
6030 	}
6031 
6032 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6033 	if (err)
6034 		goto done;
6035 
6036 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6037 	if (err)
6038 		goto done;
6039 
6040 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6041 	if (err)
6042 		goto done;
6043 
6044 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6045 	if (err)
6046 		goto done;
6047 
6048 	err = got_ref_open(&branch_ref, repo, branch_ref_name, 0);
6049 	if (err)
6050 		goto done;
6051 
6052 	err = got_ref_open(branch, repo,
6053 	    got_ref_get_symref_target(branch_ref), 0);
6054 	if (err)
6055 		goto done;
6056 
6057 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6058 	if (err)
6059 		goto done;
6060 
6061 	err = got_ref_resolve(commit_id, repo, commit_ref);
6062 	if (err)
6063 		goto done;
6064 
6065 	err = got_ref_open(new_base_branch, repo,
6066 	    new_base_branch_ref_name, 0);
6067 	if (err)
6068 		goto done;
6069 
6070 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
6071 	if (err)
6072 		goto done;
6073 done:
6074 	free(commit_ref_name);
6075 	free(branch_ref_name);
6076 	free(fileindex_path);
6077 	if (commit_ref)
6078 		got_ref_close(commit_ref);
6079 	if (branch_ref)
6080 		got_ref_close(branch_ref);
6081 	if (err) {
6082 		free(*commit_id);
6083 		*commit_id = NULL;
6084 		if (*tmp_branch) {
6085 			got_ref_close(*tmp_branch);
6086 			*tmp_branch = NULL;
6087 		}
6088 		if (*new_base_branch) {
6089 			got_ref_close(*new_base_branch);
6090 			*new_base_branch = NULL;
6091 		}
6092 		if (*branch) {
6093 			got_ref_close(*branch);
6094 			*branch = NULL;
6095 		}
6096 		if (*fileindex) {
6097 			got_fileindex_free(*fileindex);
6098 			*fileindex = NULL;
6099 		}
6100 		lock_worktree(worktree, LOCK_SH);
6101 	}
6102 	return err;
6103 }
6104 
6105 const struct got_error *
6106 got_worktree_rebase_in_progress(int *in_progress, struct got_worktree *worktree)
6107 {
6108 	const struct got_error *err;
6109 	char *tmp_branch_name = NULL;
6110 
6111 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6112 	if (err)
6113 		return err;
6114 
6115 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
6116 	free(tmp_branch_name);
6117 	return NULL;
6118 }
6119 
6120 static const struct got_error *
6121 collect_rebase_commit_msg(struct got_pathlist_head *commitable_paths,
6122     char **logmsg, void *arg)
6123 {
6124 	*logmsg = arg;
6125 	return NULL;
6126 }
6127 
6128 static const struct got_error *
6129 rebase_status(void *arg, unsigned char status, unsigned char staged_status,
6130     const char *path, struct got_object_id *blob_id,
6131     struct got_object_id *staged_blob_id, struct got_object_id *commit_id,
6132     int dirfd, const char *de_name)
6133 {
6134 	return NULL;
6135 }
6136 
6137 struct collect_merged_paths_arg {
6138 	got_worktree_checkout_cb progress_cb;
6139 	void *progress_arg;
6140 	struct got_pathlist_head *merged_paths;
6141 };
6142 
6143 static const struct got_error *
6144 collect_merged_paths(void *arg, unsigned char status, const char *path)
6145 {
6146 	const struct got_error *err;
6147 	struct collect_merged_paths_arg *a = arg;
6148 	char *p;
6149 	struct got_pathlist_entry *new;
6150 
6151 	err = (*a->progress_cb)(a->progress_arg, status, path);
6152 	if (err)
6153 		return err;
6154 
6155 	if (status != GOT_STATUS_MERGE &&
6156 	    status != GOT_STATUS_ADD &&
6157 	    status != GOT_STATUS_DELETE &&
6158 	    status != GOT_STATUS_CONFLICT)
6159 		return NULL;
6160 
6161 	p = strdup(path);
6162 	if (p == NULL)
6163 		return got_error_from_errno("strdup");
6164 
6165 	err = got_pathlist_insert(&new, a->merged_paths, p, NULL);
6166 	if (err || new == NULL)
6167 		free(p);
6168 	return err;
6169 }
6170 
6171 void
6172 got_worktree_rebase_pathlist_free(struct got_pathlist_head *merged_paths)
6173 {
6174 	struct got_pathlist_entry *pe;
6175 
6176 	TAILQ_FOREACH(pe, merged_paths, entry)
6177 		free((char *)pe->path);
6178 
6179 	got_pathlist_free(merged_paths);
6180 }
6181 
6182 static const struct got_error *
6183 store_commit_id(const char *commit_ref_name, struct got_object_id *commit_id,
6184     int is_rebase, struct got_repository *repo)
6185 {
6186 	const struct got_error *err;
6187 	struct got_reference *commit_ref = NULL;
6188 
6189 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6190 	if (err) {
6191 		if (err->code != GOT_ERR_NOT_REF)
6192 			goto done;
6193 		err = got_ref_alloc(&commit_ref, commit_ref_name, commit_id);
6194 		if (err)
6195 			goto done;
6196 		err = got_ref_write(commit_ref, repo);
6197 		if (err)
6198 			goto done;
6199 	} else if (is_rebase) {
6200 		struct got_object_id *stored_id;
6201 		int cmp;
6202 
6203 		err = got_ref_resolve(&stored_id, repo, commit_ref);
6204 		if (err)
6205 			goto done;
6206 		cmp = got_object_id_cmp(commit_id, stored_id);
6207 		free(stored_id);
6208 		if (cmp != 0) {
6209 			err = got_error(GOT_ERR_REBASE_COMMITID);
6210 			goto done;
6211 		}
6212 	}
6213 done:
6214 	if (commit_ref)
6215 		got_ref_close(commit_ref);
6216 	return err;
6217 }
6218 
6219 static const struct got_error *
6220 rebase_merge_files(struct got_pathlist_head *merged_paths,
6221     const char *commit_ref_name, struct got_worktree *worktree,
6222     struct got_fileindex *fileindex, struct got_object_id *parent_commit_id,
6223     struct got_object_id *commit_id, struct got_repository *repo,
6224     got_worktree_checkout_cb progress_cb, void *progress_arg,
6225     got_cancel_cb cancel_cb, void *cancel_arg)
6226 {
6227 	const struct got_error *err;
6228 	struct got_reference *commit_ref = NULL;
6229 	struct collect_merged_paths_arg cmp_arg;
6230 	char *fileindex_path;
6231 
6232 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6233 
6234 	err = get_fileindex_path(&fileindex_path, worktree);
6235 	if (err)
6236 		return err;
6237 
6238 	cmp_arg.progress_cb = progress_cb;
6239 	cmp_arg.progress_arg = progress_arg;
6240 	cmp_arg.merged_paths = merged_paths;
6241 	err = merge_files(worktree, fileindex, fileindex_path,
6242 	    parent_commit_id, commit_id, repo, collect_merged_paths,
6243 	    &cmp_arg, cancel_cb, cancel_arg);
6244 	if (commit_ref)
6245 		got_ref_close(commit_ref);
6246 	return err;
6247 }
6248 
6249 const struct got_error *
6250 got_worktree_rebase_merge_files(struct got_pathlist_head *merged_paths,
6251     struct got_worktree *worktree, struct got_fileindex *fileindex,
6252     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6253     struct got_repository *repo,
6254     got_worktree_checkout_cb progress_cb, void *progress_arg,
6255     got_cancel_cb cancel_cb, void *cancel_arg)
6256 {
6257 	const struct got_error *err;
6258 	char *commit_ref_name;
6259 
6260 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6261 	if (err)
6262 		return err;
6263 
6264 	err = store_commit_id(commit_ref_name, commit_id, 1, repo);
6265 	if (err)
6266 		goto done;
6267 
6268 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6269 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6270 	    progress_arg, cancel_cb, cancel_arg);
6271 done:
6272 	free(commit_ref_name);
6273 	return err;
6274 }
6275 
6276 const struct got_error *
6277 got_worktree_histedit_merge_files(struct got_pathlist_head *merged_paths,
6278     struct got_worktree *worktree, struct got_fileindex *fileindex,
6279     struct got_object_id *parent_commit_id, struct got_object_id *commit_id,
6280     struct got_repository *repo,
6281     got_worktree_checkout_cb progress_cb, void *progress_arg,
6282     got_cancel_cb cancel_cb, void *cancel_arg)
6283 {
6284 	const struct got_error *err;
6285 	char *commit_ref_name;
6286 
6287 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6288 	if (err)
6289 		return err;
6290 
6291 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
6292 	if (err)
6293 		goto done;
6294 
6295 	err = rebase_merge_files(merged_paths, commit_ref_name, worktree,
6296 	    fileindex, parent_commit_id, commit_id, repo, progress_cb,
6297 	    progress_arg, cancel_cb, cancel_arg);
6298 done:
6299 	free(commit_ref_name);
6300 	return err;
6301 }
6302 
6303 static const struct got_error *
6304 rebase_commit(struct got_object_id **new_commit_id,
6305     struct got_pathlist_head *merged_paths, struct got_reference *commit_ref,
6306     struct got_worktree *worktree, struct got_fileindex *fileindex,
6307     struct got_reference *tmp_branch, struct got_commit_object *orig_commit,
6308     const char *new_logmsg, struct got_repository *repo)
6309 {
6310 	const struct got_error *err, *sync_err;
6311 	struct got_pathlist_head commitable_paths;
6312 	struct collect_commitables_arg cc_arg;
6313 	char *fileindex_path = NULL;
6314 	struct got_reference *head_ref = NULL;
6315 	struct got_object_id *head_commit_id = NULL;
6316 	char *logmsg = NULL;
6317 
6318 	TAILQ_INIT(&commitable_paths);
6319 	*new_commit_id = NULL;
6320 
6321 	/* Work tree is locked/unlocked during rebase preparation/teardown. */
6322 
6323 	err = get_fileindex_path(&fileindex_path, worktree);
6324 	if (err)
6325 		return err;
6326 
6327 	cc_arg.commitable_paths = &commitable_paths;
6328 	cc_arg.worktree = worktree;
6329 	cc_arg.repo = repo;
6330 	cc_arg.have_staged_files = 0;
6331 	/*
6332 	 * If possible get the status of individual files directly to
6333 	 * avoid crawling the entire work tree once per rebased commit.
6334 	 * TODO: Ideally, merged_paths would contain a list of commitables
6335 	 * we could use so we could skip worktree_status() entirely.
6336 	 */
6337 	if (merged_paths) {
6338 		struct got_pathlist_entry *pe;
6339 		TAILQ_FOREACH(pe, merged_paths, entry) {
6340 			err = worktree_status(worktree, pe->path, fileindex,
6341 			    repo, collect_commitables, &cc_arg, NULL, NULL, 0,
6342 			    0);
6343 			if (err)
6344 				goto done;
6345 		}
6346 	} else {
6347 		err = worktree_status(worktree, "", fileindex, repo,
6348 		    collect_commitables, &cc_arg, NULL, NULL, 0, 0);
6349 		if (err)
6350 			goto done;
6351 	}
6352 
6353 	if (TAILQ_EMPTY(&commitable_paths)) {
6354 		/* No-op change; commit will be elided. */
6355 		err = got_ref_delete(commit_ref, repo);
6356 		if (err)
6357 			goto done;
6358 		err = got_error(GOT_ERR_COMMIT_NO_CHANGES);
6359 		goto done;
6360 	}
6361 
6362 	err = got_ref_open(&head_ref, repo, worktree->head_ref_name, 0);
6363 	if (err)
6364 		goto done;
6365 
6366 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
6367 	if (err)
6368 		goto done;
6369 
6370 	if (new_logmsg) {
6371 		logmsg = strdup(new_logmsg);
6372 		if (logmsg == NULL) {
6373 			err = got_error_from_errno("strdup");
6374 			goto done;
6375 		}
6376 	} else {
6377 		err = got_object_commit_get_logmsg(&logmsg, orig_commit);
6378 		if (err)
6379 			goto done;
6380 	}
6381 
6382 	/* NB: commit_worktree will call free(logmsg) */
6383 	err = commit_worktree(new_commit_id, &commitable_paths, head_commit_id,
6384 	    worktree, got_object_commit_get_author(orig_commit),
6385 	    got_object_commit_get_committer(orig_commit),
6386 	    collect_rebase_commit_msg, logmsg, rebase_status, NULL, repo);
6387 	if (err)
6388 		goto done;
6389 
6390 	err = got_ref_change_ref(tmp_branch, *new_commit_id);
6391 	if (err)
6392 		goto done;
6393 
6394 	err = got_ref_delete(commit_ref, repo);
6395 	if (err)
6396 		goto done;
6397 
6398 	err = update_fileindex_after_commit(worktree, &commitable_paths,
6399 	    *new_commit_id, fileindex, 0);
6400 	sync_err = sync_fileindex(fileindex, fileindex_path);
6401 	if (sync_err && err == NULL)
6402 		err = sync_err;
6403 done:
6404 	free(fileindex_path);
6405 	free(head_commit_id);
6406 	if (head_ref)
6407 		got_ref_close(head_ref);
6408 	if (err) {
6409 		free(*new_commit_id);
6410 		*new_commit_id = NULL;
6411 	}
6412 	return err;
6413 }
6414 
6415 const struct got_error *
6416 got_worktree_rebase_commit(struct got_object_id **new_commit_id,
6417     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6418     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6419     struct got_commit_object *orig_commit,
6420     struct got_object_id *orig_commit_id, struct got_repository *repo)
6421 {
6422 	const struct got_error *err;
6423 	char *commit_ref_name;
6424 	struct got_reference *commit_ref = NULL;
6425 	struct got_object_id *commit_id = NULL;
6426 
6427 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6428 	if (err)
6429 		return err;
6430 
6431 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6432 	if (err)
6433 		goto done;
6434 	err = got_ref_resolve(&commit_id, repo, commit_ref);
6435 	if (err)
6436 		goto done;
6437 	if (got_object_id_cmp(commit_id, orig_commit_id) != 0) {
6438 		err = got_error(GOT_ERR_REBASE_COMMITID);
6439 		goto done;
6440 	}
6441 
6442 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6443 	    worktree, fileindex, tmp_branch, orig_commit, NULL, repo);
6444 done:
6445 	if (commit_ref)
6446 		got_ref_close(commit_ref);
6447 	free(commit_ref_name);
6448 	free(commit_id);
6449 	return err;
6450 }
6451 
6452 const struct got_error *
6453 got_worktree_histedit_commit(struct got_object_id **new_commit_id,
6454     struct got_pathlist_head *merged_paths, struct got_worktree *worktree,
6455     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
6456     struct got_commit_object *orig_commit,
6457     struct got_object_id *orig_commit_id, const char *new_logmsg,
6458     struct got_repository *repo)
6459 {
6460 	const struct got_error *err;
6461 	char *commit_ref_name;
6462 	struct got_reference *commit_ref = NULL;
6463 
6464 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6465 	if (err)
6466 		return err;
6467 
6468 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6469 	if (err)
6470 		goto done;
6471 
6472 	err = rebase_commit(new_commit_id, merged_paths, commit_ref,
6473 	    worktree, fileindex, tmp_branch, orig_commit, new_logmsg, repo);
6474 done:
6475 	if (commit_ref)
6476 		got_ref_close(commit_ref);
6477 	free(commit_ref_name);
6478 	return err;
6479 }
6480 
6481 const struct got_error *
6482 got_worktree_rebase_postpone(struct got_worktree *worktree,
6483     struct got_fileindex *fileindex)
6484 {
6485 	if (fileindex)
6486 		got_fileindex_free(fileindex);
6487 	return lock_worktree(worktree, LOCK_SH);
6488 }
6489 
6490 static const struct got_error *
6491 delete_ref(const char *name, struct got_repository *repo)
6492 {
6493 	const struct got_error *err;
6494 	struct got_reference *ref;
6495 
6496 	err = got_ref_open(&ref, repo, name, 0);
6497 	if (err) {
6498 		if (err->code == GOT_ERR_NOT_REF)
6499 			return NULL;
6500 		return err;
6501 	}
6502 
6503 	err = got_ref_delete(ref, repo);
6504 	got_ref_close(ref);
6505 	return err;
6506 }
6507 
6508 static const struct got_error *
6509 delete_rebase_refs(struct got_worktree *worktree, struct got_repository *repo)
6510 {
6511 	const struct got_error *err;
6512 	char *tmp_branch_name = NULL, *new_base_branch_ref_name = NULL;
6513 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
6514 
6515 	err = get_rebase_tmp_ref_name(&tmp_branch_name, worktree);
6516 	if (err)
6517 		goto done;
6518 	err = delete_ref(tmp_branch_name, repo);
6519 	if (err)
6520 		goto done;
6521 
6522 	err = get_newbase_symref_name(&new_base_branch_ref_name, worktree);
6523 	if (err)
6524 		goto done;
6525 	err = delete_ref(new_base_branch_ref_name, repo);
6526 	if (err)
6527 		goto done;
6528 
6529 	err = get_rebase_branch_symref_name(&branch_ref_name, worktree);
6530 	if (err)
6531 		goto done;
6532 	err = delete_ref(branch_ref_name, repo);
6533 	if (err)
6534 		goto done;
6535 
6536 	err = get_rebase_commit_ref_name(&commit_ref_name, worktree);
6537 	if (err)
6538 		goto done;
6539 	err = delete_ref(commit_ref_name, repo);
6540 	if (err)
6541 		goto done;
6542 
6543 done:
6544 	free(tmp_branch_name);
6545 	free(new_base_branch_ref_name);
6546 	free(branch_ref_name);
6547 	free(commit_ref_name);
6548 	return err;
6549 }
6550 
6551 const struct got_error *
6552 create_backup_ref(const char *backup_ref_prefix, struct got_reference *branch,
6553     struct got_object_id *new_commit_id, struct got_repository *repo)
6554 {
6555 	const struct got_error *err;
6556 	struct got_reference *ref = NULL;
6557 	struct got_object_id *old_commit_id = NULL;
6558 	const char *branch_name = NULL;
6559 	char *new_id_str = NULL;
6560 	char *refname = NULL;
6561 
6562 	branch_name = got_ref_get_name(branch);
6563 	if (strncmp(branch_name, "refs/heads/", 11) != 0)
6564 		return got_error(GOT_ERR_BAD_REF_NAME); /* should not happen */
6565 	branch_name += 11;
6566 
6567 	err = got_object_id_str(&new_id_str, new_commit_id);
6568 	if (err)
6569 		return err;
6570 
6571 	if (asprintf(&refname, "%s/%s/%s", backup_ref_prefix, branch_name,
6572 	    new_id_str) == -1) {
6573 		err = got_error_from_errno("asprintf");
6574 		goto done;
6575 	}
6576 
6577 	err = got_ref_resolve(&old_commit_id, repo, branch);
6578 	if (err)
6579 		goto done;
6580 
6581 	err = got_ref_alloc(&ref, refname, old_commit_id);
6582 	if (err)
6583 		goto done;
6584 
6585 	err = got_ref_write(ref, repo);
6586 done:
6587 	free(new_id_str);
6588 	free(refname);
6589 	free(old_commit_id);
6590 	if (ref)
6591 		got_ref_close(ref);
6592 	return err;
6593 }
6594 
6595 const struct got_error *
6596 got_worktree_rebase_complete(struct got_worktree *worktree,
6597     struct got_fileindex *fileindex, struct got_reference *new_base_branch,
6598     struct got_reference *tmp_branch, struct got_reference *rebased_branch,
6599     struct got_repository *repo, int create_backup)
6600 {
6601 	const struct got_error *err, *unlockerr, *sync_err;
6602 	struct got_object_id *new_head_commit_id = NULL;
6603 	char *fileindex_path = NULL;
6604 
6605 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
6606 	if (err)
6607 		return err;
6608 
6609 	if (create_backup) {
6610 		err = create_backup_ref(GOT_WORKTREE_REBASE_BACKUP_REF_PREFIX,
6611 		    rebased_branch, new_head_commit_id, repo);
6612 		if (err)
6613 			goto done;
6614 	}
6615 
6616 	err = got_ref_change_ref(rebased_branch, new_head_commit_id);
6617 	if (err)
6618 		goto done;
6619 
6620 	err = got_ref_write(rebased_branch, repo);
6621 	if (err)
6622 		goto done;
6623 
6624 	err = got_worktree_set_head_ref(worktree, rebased_branch);
6625 	if (err)
6626 		goto done;
6627 
6628 	err = delete_rebase_refs(worktree, repo);
6629 	if (err)
6630 		goto done;
6631 
6632 	err = get_fileindex_path(&fileindex_path, worktree);
6633 	if (err)
6634 		goto done;
6635 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
6636 	sync_err = sync_fileindex(fileindex, fileindex_path);
6637 	if (sync_err && err == NULL)
6638 		err = sync_err;
6639 done:
6640 	got_fileindex_free(fileindex);
6641 	free(fileindex_path);
6642 	free(new_head_commit_id);
6643 	unlockerr = lock_worktree(worktree, LOCK_SH);
6644 	if (unlockerr && err == NULL)
6645 		err = unlockerr;
6646 	return err;
6647 }
6648 
6649 const struct got_error *
6650 got_worktree_rebase_abort(struct got_worktree *worktree,
6651     struct got_fileindex *fileindex, struct got_repository *repo,
6652     struct got_reference *new_base_branch,
6653      got_worktree_checkout_cb progress_cb, void *progress_arg)
6654 {
6655 	const struct got_error *err, *unlockerr, *sync_err;
6656 	struct got_reference *resolved = NULL;
6657 	struct got_object_id *commit_id = NULL;
6658 	char *fileindex_path = NULL;
6659 	struct revert_file_args rfa;
6660 	struct got_object_id *tree_id = NULL;
6661 
6662 	err = lock_worktree(worktree, LOCK_EX);
6663 	if (err)
6664 		return err;
6665 
6666 	err = got_ref_open(&resolved, repo,
6667 	    got_ref_get_symref_target(new_base_branch), 0);
6668 	if (err)
6669 		goto done;
6670 
6671 	err = got_worktree_set_head_ref(worktree, resolved);
6672 	if (err)
6673 		goto done;
6674 
6675 	/*
6676 	 * XXX commits to the base branch could have happened while
6677 	 * we were busy rebasing; should we store the original commit ID
6678 	 * when rebase begins and read it back here?
6679 	 */
6680 	err = got_ref_resolve(&commit_id, repo, resolved);
6681 	if (err)
6682 		goto done;
6683 
6684 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
6685 	if (err)
6686 		goto done;
6687 
6688 	err = got_object_id_by_path(&tree_id, repo,
6689 	    worktree->base_commit_id, worktree->path_prefix);
6690 	if (err)
6691 		goto done;
6692 
6693 	err = delete_rebase_refs(worktree, repo);
6694 	if (err)
6695 		goto done;
6696 
6697 	err = get_fileindex_path(&fileindex_path, worktree);
6698 	if (err)
6699 		goto done;
6700 
6701 	rfa.worktree = worktree;
6702 	rfa.fileindex = fileindex;
6703 	rfa.progress_cb = progress_cb;
6704 	rfa.progress_arg = progress_arg;
6705 	rfa.patch_cb = NULL;
6706 	rfa.patch_arg = NULL;
6707 	rfa.repo = repo;
6708 	err = worktree_status(worktree, "", fileindex, repo,
6709 	    revert_file, &rfa, NULL, NULL, 0, 0);
6710 	if (err)
6711 		goto sync;
6712 
6713 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
6714 	    repo, progress_cb, progress_arg, NULL, NULL);
6715 sync:
6716 	sync_err = sync_fileindex(fileindex, fileindex_path);
6717 	if (sync_err && err == NULL)
6718 		err = sync_err;
6719 done:
6720 	got_ref_close(resolved);
6721 	free(tree_id);
6722 	free(commit_id);
6723 	if (fileindex)
6724 		got_fileindex_free(fileindex);
6725 	free(fileindex_path);
6726 
6727 	unlockerr = lock_worktree(worktree, LOCK_SH);
6728 	if (unlockerr && err == NULL)
6729 		err = unlockerr;
6730 	return err;
6731 }
6732 
6733 const struct got_error *
6734 got_worktree_histedit_prepare(struct got_reference **tmp_branch,
6735     struct got_reference **branch_ref, struct got_object_id **base_commit_id,
6736     struct got_fileindex **fileindex, struct got_worktree *worktree,
6737     struct got_repository *repo)
6738 {
6739 	const struct got_error *err = NULL;
6740 	char *tmp_branch_name = NULL;
6741 	char *branch_ref_name = NULL;
6742 	char *base_commit_ref_name = NULL;
6743 	char *fileindex_path = NULL;
6744 	struct check_rebase_ok_arg ok_arg;
6745 	struct got_reference *wt_branch = NULL;
6746 	struct got_reference *base_commit_ref = NULL;
6747 
6748 	*tmp_branch = NULL;
6749 	*branch_ref = NULL;
6750 	*base_commit_id = NULL;
6751 	*fileindex = NULL;
6752 
6753 	err = lock_worktree(worktree, LOCK_EX);
6754 	if (err)
6755 		return err;
6756 
6757 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6758 	if (err)
6759 		goto done;
6760 
6761 	ok_arg.worktree = worktree;
6762 	ok_arg.repo = repo;
6763 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
6764 	    &ok_arg);
6765 	if (err)
6766 		goto done;
6767 
6768 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
6769 	if (err)
6770 		goto done;
6771 
6772 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
6773 	if (err)
6774 		goto done;
6775 
6776 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
6777 	    worktree);
6778 	if (err)
6779 		goto done;
6780 
6781 	err = got_ref_open(&wt_branch, repo, worktree->head_ref_name,
6782 	    0);
6783 	if (err)
6784 		goto done;
6785 
6786 	err = got_ref_alloc_symref(branch_ref, branch_ref_name, wt_branch);
6787 	if (err)
6788 		goto done;
6789 
6790 	err = got_ref_write(*branch_ref, repo);
6791 	if (err)
6792 		goto done;
6793 
6794 	err = got_ref_alloc(&base_commit_ref, base_commit_ref_name,
6795 	    worktree->base_commit_id);
6796 	if (err)
6797 		goto done;
6798 	err = got_ref_write(base_commit_ref, repo);
6799 	if (err)
6800 		goto done;
6801 	*base_commit_id = got_object_id_dup(worktree->base_commit_id);
6802 	if (*base_commit_id == NULL) {
6803 		err = got_error_from_errno("got_object_id_dup");
6804 		goto done;
6805 	}
6806 
6807 	err = got_ref_alloc(tmp_branch, tmp_branch_name,
6808 	    worktree->base_commit_id);
6809 	if (err)
6810 		goto done;
6811 	err = got_ref_write(*tmp_branch, repo);
6812 	if (err)
6813 		goto done;
6814 
6815 	err = got_worktree_set_head_ref(worktree, *tmp_branch);
6816 	if (err)
6817 		goto done;
6818 done:
6819 	free(fileindex_path);
6820 	free(tmp_branch_name);
6821 	free(branch_ref_name);
6822 	free(base_commit_ref_name);
6823 	if (wt_branch)
6824 		got_ref_close(wt_branch);
6825 	if (err) {
6826 		if (*branch_ref) {
6827 			got_ref_close(*branch_ref);
6828 			*branch_ref = NULL;
6829 		}
6830 		if (*tmp_branch) {
6831 			got_ref_close(*tmp_branch);
6832 			*tmp_branch = NULL;
6833 		}
6834 		free(*base_commit_id);
6835 		if (*fileindex) {
6836 			got_fileindex_free(*fileindex);
6837 			*fileindex = NULL;
6838 		}
6839 		lock_worktree(worktree, LOCK_SH);
6840 	}
6841 	return err;
6842 }
6843 
6844 const struct got_error *
6845 got_worktree_histedit_postpone(struct got_worktree *worktree,
6846     struct got_fileindex *fileindex)
6847 {
6848 	if (fileindex)
6849 		got_fileindex_free(fileindex);
6850 	return lock_worktree(worktree, LOCK_SH);
6851 }
6852 
6853 const struct got_error *
6854 got_worktree_histedit_in_progress(int *in_progress,
6855     struct got_worktree *worktree)
6856 {
6857 	const struct got_error *err;
6858 	char *tmp_branch_name = NULL;
6859 
6860 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
6861 	if (err)
6862 		return err;
6863 
6864 	*in_progress = (strcmp(tmp_branch_name, worktree->head_ref_name) == 0);
6865 	free(tmp_branch_name);
6866 	return NULL;
6867 }
6868 
6869 const struct got_error *
6870 got_worktree_histedit_continue(struct got_object_id **commit_id,
6871     struct got_reference **tmp_branch, struct got_reference **branch_ref,
6872     struct got_object_id **base_commit_id, struct got_fileindex **fileindex,
6873     struct got_worktree *worktree, struct got_repository *repo)
6874 {
6875 	const struct got_error *err;
6876 	char *commit_ref_name = NULL, *base_commit_ref_name = NULL;
6877 	char *tmp_branch_name = NULL, *branch_ref_name = NULL;
6878 	struct got_reference *commit_ref = NULL;
6879 	struct got_reference *base_commit_ref = NULL;
6880 	char *fileindex_path = NULL;
6881 	int have_staged_files = 0;
6882 
6883 	*commit_id = NULL;
6884 	*tmp_branch = NULL;
6885 	*base_commit_id = NULL;
6886 	*fileindex = NULL;
6887 
6888 	err = lock_worktree(worktree, LOCK_EX);
6889 	if (err)
6890 		return err;
6891 
6892 	err = open_fileindex(fileindex, &fileindex_path, worktree);
6893 	if (err)
6894 		goto done;
6895 
6896 	err = got_fileindex_for_each_entry_safe(*fileindex, check_staged_file,
6897 	    &have_staged_files);
6898 	if (err && err->code != GOT_ERR_CANCELLED)
6899 		goto done;
6900 	if (have_staged_files) {
6901 		err = got_error(GOT_ERR_STAGED_PATHS);
6902 		goto done;
6903 	}
6904 
6905 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
6906 	if (err)
6907 		goto done;
6908 
6909 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
6910 	if (err)
6911 		goto done;
6912 
6913 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6914 	if (err)
6915 		goto done;
6916 
6917 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
6918 	    worktree);
6919 	if (err)
6920 		goto done;
6921 
6922 	err = got_ref_open(branch_ref, repo, branch_ref_name, 0);
6923 	if (err)
6924 		goto done;
6925 
6926 	err = got_ref_open(&commit_ref, repo, commit_ref_name, 0);
6927 	if (err)
6928 		goto done;
6929 	err = got_ref_resolve(commit_id, repo, commit_ref);
6930 	if (err)
6931 		goto done;
6932 
6933 	err = got_ref_open(&base_commit_ref, repo, base_commit_ref_name, 0);
6934 	if (err)
6935 		goto done;
6936 	err = got_ref_resolve(base_commit_id, repo, base_commit_ref);
6937 	if (err)
6938 		goto done;
6939 
6940 	err = got_ref_open(tmp_branch, repo, tmp_branch_name, 0);
6941 	if (err)
6942 		goto done;
6943 done:
6944 	free(commit_ref_name);
6945 	free(branch_ref_name);
6946 	free(fileindex_path);
6947 	if (commit_ref)
6948 		got_ref_close(commit_ref);
6949 	if (base_commit_ref)
6950 		got_ref_close(base_commit_ref);
6951 	if (err) {
6952 		free(*commit_id);
6953 		*commit_id = NULL;
6954 		free(*base_commit_id);
6955 		*base_commit_id = NULL;
6956 		if (*tmp_branch) {
6957 			got_ref_close(*tmp_branch);
6958 			*tmp_branch = NULL;
6959 		}
6960 		if (*fileindex) {
6961 			got_fileindex_free(*fileindex);
6962 			*fileindex = NULL;
6963 		}
6964 		lock_worktree(worktree, LOCK_EX);
6965 	}
6966 	return err;
6967 }
6968 
6969 static const struct got_error *
6970 delete_histedit_refs(struct got_worktree *worktree, struct got_repository *repo)
6971 {
6972 	const struct got_error *err;
6973 	char *tmp_branch_name = NULL, *base_commit_ref_name = NULL;
6974 	char *branch_ref_name = NULL, *commit_ref_name = NULL;
6975 
6976 	err = get_histedit_tmp_ref_name(&tmp_branch_name, worktree);
6977 	if (err)
6978 		goto done;
6979 	err = delete_ref(tmp_branch_name, repo);
6980 	if (err)
6981 		goto done;
6982 
6983 	err = get_histedit_base_commit_ref_name(&base_commit_ref_name,
6984 	    worktree);
6985 	if (err)
6986 		goto done;
6987 	err = delete_ref(base_commit_ref_name, repo);
6988 	if (err)
6989 		goto done;
6990 
6991 	err = get_histedit_branch_symref_name(&branch_ref_name, worktree);
6992 	if (err)
6993 		goto done;
6994 	err = delete_ref(branch_ref_name, repo);
6995 	if (err)
6996 		goto done;
6997 
6998 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
6999 	if (err)
7000 		goto done;
7001 	err = delete_ref(commit_ref_name, repo);
7002 	if (err)
7003 		goto done;
7004 done:
7005 	free(tmp_branch_name);
7006 	free(base_commit_ref_name);
7007 	free(branch_ref_name);
7008 	free(commit_ref_name);
7009 	return err;
7010 }
7011 
7012 const struct got_error *
7013 got_worktree_histedit_abort(struct got_worktree *worktree,
7014     struct got_fileindex *fileindex, struct got_repository *repo,
7015     struct got_reference *branch, struct got_object_id *base_commit_id,
7016     got_worktree_checkout_cb progress_cb, void *progress_arg)
7017 {
7018 	const struct got_error *err, *unlockerr, *sync_err;
7019 	struct got_reference *resolved = NULL;
7020 	char *fileindex_path = NULL;
7021 	struct got_object_id *tree_id = NULL;
7022 	struct revert_file_args rfa;
7023 
7024 	err = lock_worktree(worktree, LOCK_EX);
7025 	if (err)
7026 		return err;
7027 
7028 	err = got_ref_open(&resolved, repo,
7029 	    got_ref_get_symref_target(branch), 0);
7030 	if (err)
7031 		goto done;
7032 
7033 	err = got_worktree_set_head_ref(worktree, resolved);
7034 	if (err)
7035 		goto done;
7036 
7037 	err = got_worktree_set_base_commit_id(worktree, repo, base_commit_id);
7038 	if (err)
7039 		goto done;
7040 
7041 	err = got_object_id_by_path(&tree_id, repo, base_commit_id,
7042 	    worktree->path_prefix);
7043 	if (err)
7044 		goto done;
7045 
7046 	err = delete_histedit_refs(worktree, repo);
7047 	if (err)
7048 		goto done;
7049 
7050 	err = get_fileindex_path(&fileindex_path, worktree);
7051 	if (err)
7052 		goto done;
7053 
7054 	rfa.worktree = worktree;
7055 	rfa.fileindex = fileindex;
7056 	rfa.progress_cb = progress_cb;
7057 	rfa.progress_arg = progress_arg;
7058 	rfa.patch_cb = NULL;
7059 	rfa.patch_arg = NULL;
7060 	rfa.repo = repo;
7061 	err = worktree_status(worktree, "", fileindex, repo,
7062 	    revert_file, &rfa, NULL, NULL, 0, 0);
7063 	if (err)
7064 		goto sync;
7065 
7066 	err = checkout_files(worktree, fileindex, "", tree_id, NULL,
7067 	    repo, progress_cb, progress_arg, NULL, NULL);
7068 sync:
7069 	sync_err = sync_fileindex(fileindex, fileindex_path);
7070 	if (sync_err && err == NULL)
7071 		err = sync_err;
7072 done:
7073 	got_ref_close(resolved);
7074 	free(tree_id);
7075 	free(fileindex_path);
7076 
7077 	unlockerr = lock_worktree(worktree, LOCK_SH);
7078 	if (unlockerr && err == NULL)
7079 		err = unlockerr;
7080 	return err;
7081 }
7082 
7083 const struct got_error *
7084 got_worktree_histedit_complete(struct got_worktree *worktree,
7085     struct got_fileindex *fileindex, struct got_reference *tmp_branch,
7086     struct got_reference *edited_branch, struct got_repository *repo)
7087 {
7088 	const struct got_error *err, *unlockerr, *sync_err;
7089 	struct got_object_id *new_head_commit_id = NULL;
7090 	struct got_reference *resolved = NULL;
7091 	char *fileindex_path = NULL;
7092 
7093 	err = got_ref_resolve(&new_head_commit_id, repo, tmp_branch);
7094 	if (err)
7095 		return err;
7096 
7097 	err = got_ref_open(&resolved, repo,
7098 	    got_ref_get_symref_target(edited_branch), 0);
7099 	if (err)
7100 		goto done;
7101 
7102 	err = create_backup_ref(GOT_WORKTREE_HISTEDIT_BACKUP_REF_PREFIX,
7103 	    resolved, new_head_commit_id, repo);
7104 	if (err)
7105 		goto done;
7106 
7107 	err = got_ref_change_ref(resolved, new_head_commit_id);
7108 	if (err)
7109 		goto done;
7110 
7111 	err = got_ref_write(resolved, repo);
7112 	if (err)
7113 		goto done;
7114 
7115 	err = got_worktree_set_head_ref(worktree, resolved);
7116 	if (err)
7117 		goto done;
7118 
7119 	err = delete_histedit_refs(worktree, repo);
7120 	if (err)
7121 		goto done;
7122 
7123 	err = get_fileindex_path(&fileindex_path, worktree);
7124 	if (err)
7125 		goto done;
7126 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7127 	sync_err = sync_fileindex(fileindex, fileindex_path);
7128 	if (sync_err && err == NULL)
7129 		err = sync_err;
7130 done:
7131 	got_fileindex_free(fileindex);
7132 	free(fileindex_path);
7133 	free(new_head_commit_id);
7134 	unlockerr = lock_worktree(worktree, LOCK_SH);
7135 	if (unlockerr && err == NULL)
7136 		err = unlockerr;
7137 	return err;
7138 }
7139 
7140 const struct got_error *
7141 got_worktree_histedit_skip_commit(struct got_worktree *worktree,
7142     struct got_object_id *commit_id, struct got_repository *repo)
7143 {
7144 	const struct got_error *err;
7145 	char *commit_ref_name;
7146 
7147 	err = get_histedit_commit_ref_name(&commit_ref_name, worktree);
7148 	if (err)
7149 		return err;
7150 
7151 	err = store_commit_id(commit_ref_name, commit_id, 0, repo);
7152 	if (err)
7153 		goto done;
7154 
7155 	err = delete_ref(commit_ref_name, repo);
7156 done:
7157 	free(commit_ref_name);
7158 	return err;
7159 }
7160 
7161 const struct got_error *
7162 got_worktree_integrate_prepare(struct got_fileindex **fileindex,
7163     struct got_reference **branch_ref, struct got_reference **base_branch_ref,
7164     struct got_worktree *worktree, const char *refname,
7165     struct got_repository *repo)
7166 {
7167 	const struct got_error *err = NULL;
7168 	char *fileindex_path = NULL;
7169 	struct check_rebase_ok_arg ok_arg;
7170 
7171 	*fileindex = NULL;
7172 	*branch_ref = NULL;
7173 	*base_branch_ref = NULL;
7174 
7175 	err = lock_worktree(worktree, LOCK_EX);
7176 	if (err)
7177 		return err;
7178 
7179 	if (strcmp(refname, got_worktree_get_head_ref_name(worktree)) == 0) {
7180 		err = got_error_msg(GOT_ERR_SAME_BRANCH,
7181 		    "cannot integrate a branch into itself; "
7182 		    "update -b or different branch name required");
7183 		goto done;
7184 	}
7185 
7186 	err = open_fileindex(fileindex, &fileindex_path, worktree);
7187 	if (err)
7188 		goto done;
7189 
7190 	/* Preconditions are the same as for rebase. */
7191 	ok_arg.worktree = worktree;
7192 	ok_arg.repo = repo;
7193 	err = got_fileindex_for_each_entry_safe(*fileindex, check_rebase_ok,
7194 	    &ok_arg);
7195 	if (err)
7196 		goto done;
7197 
7198 	err = got_ref_open(branch_ref, repo, refname, 1);
7199 	if (err)
7200 		goto done;
7201 
7202 	err = got_ref_open(base_branch_ref, repo,
7203 	    got_worktree_get_head_ref_name(worktree), 1);
7204 done:
7205 	if (err) {
7206 		if (*branch_ref) {
7207 			got_ref_close(*branch_ref);
7208 			*branch_ref = NULL;
7209 		}
7210 		if (*base_branch_ref) {
7211 			got_ref_close(*base_branch_ref);
7212 			*base_branch_ref = NULL;
7213 		}
7214 		if (*fileindex) {
7215 			got_fileindex_free(*fileindex);
7216 			*fileindex = NULL;
7217 		}
7218 		lock_worktree(worktree, LOCK_SH);
7219 	}
7220 	return err;
7221 }
7222 
7223 const struct got_error *
7224 got_worktree_integrate_continue(struct got_worktree *worktree,
7225     struct got_fileindex *fileindex, struct got_repository *repo,
7226     struct got_reference *branch_ref, struct got_reference *base_branch_ref,
7227     got_worktree_checkout_cb progress_cb, void *progress_arg,
7228     got_cancel_cb cancel_cb, void *cancel_arg)
7229 {
7230 	const struct got_error *err = NULL, *sync_err, *unlockerr;
7231 	char *fileindex_path = NULL;
7232 	struct got_object_id *tree_id = NULL, *commit_id = NULL;
7233 
7234 	err = get_fileindex_path(&fileindex_path, worktree);
7235 	if (err)
7236 		goto done;
7237 
7238 	err = got_ref_resolve(&commit_id, repo, branch_ref);
7239 	if (err)
7240 		goto done;
7241 
7242 	err = got_object_id_by_path(&tree_id, repo, commit_id,
7243 	    worktree->path_prefix);
7244 	if (err)
7245 		goto done;
7246 
7247 	err = got_worktree_set_base_commit_id(worktree, repo, commit_id);
7248 	if (err)
7249 		goto done;
7250 
7251 	err = checkout_files(worktree, fileindex, "", tree_id, NULL, repo,
7252 	    progress_cb, progress_arg, cancel_cb, cancel_arg);
7253 	if (err)
7254 		goto sync;
7255 
7256 	err = got_ref_change_ref(base_branch_ref, commit_id);
7257 	if (err)
7258 		goto sync;
7259 
7260 	err = got_ref_write(base_branch_ref, repo);
7261 	if (err)
7262 		goto sync;
7263 
7264 	err = bump_base_commit_id_everywhere(worktree, fileindex, NULL, NULL);
7265 sync:
7266 	sync_err = sync_fileindex(fileindex, fileindex_path);
7267 	if (sync_err && err == NULL)
7268 		err = sync_err;
7269 
7270 done:
7271 	unlockerr = got_ref_unlock(branch_ref);
7272 	if (unlockerr && err == NULL)
7273 		err = unlockerr;
7274 	got_ref_close(branch_ref);
7275 
7276 	unlockerr = got_ref_unlock(base_branch_ref);
7277 	if (unlockerr && err == NULL)
7278 		err = unlockerr;
7279 	got_ref_close(base_branch_ref);
7280 
7281 	got_fileindex_free(fileindex);
7282 	free(fileindex_path);
7283 	free(tree_id);
7284 
7285 	unlockerr = lock_worktree(worktree, LOCK_SH);
7286 	if (unlockerr && err == NULL)
7287 		err = unlockerr;
7288 	return err;
7289 }
7290 
7291 const struct got_error *
7292 got_worktree_integrate_abort(struct got_worktree *worktree,
7293     struct got_fileindex *fileindex, struct got_repository *repo,
7294     struct got_reference *branch_ref, struct got_reference *base_branch_ref)
7295 {
7296 	const struct got_error *err = NULL, *unlockerr = NULL;
7297 
7298 	got_fileindex_free(fileindex);
7299 
7300 	err = lock_worktree(worktree, LOCK_SH);
7301 
7302 	unlockerr = got_ref_unlock(branch_ref);
7303 	if (unlockerr && err == NULL)
7304 		err = unlockerr;
7305 	got_ref_close(branch_ref);
7306 
7307 	unlockerr = got_ref_unlock(base_branch_ref);
7308 	if (unlockerr && err == NULL)
7309 		err = unlockerr;
7310 	got_ref_close(base_branch_ref);
7311 
7312 	return err;
7313 }
7314 
7315 struct check_stage_ok_arg {
7316 	struct got_object_id *head_commit_id;
7317 	struct got_worktree *worktree;
7318 	struct got_fileindex *fileindex;
7319 	struct got_repository *repo;
7320 	int have_changes;
7321 };
7322 
7323 const struct got_error *
7324 check_stage_ok(void *arg, unsigned char status,
7325     unsigned char staged_status, const char *relpath,
7326     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
7327     struct got_object_id *commit_id, int dirfd, const char *de_name)
7328 {
7329 	struct check_stage_ok_arg *a = arg;
7330 	const struct got_error *err = NULL;
7331 	struct got_fileindex_entry *ie;
7332 	struct got_object_id base_commit_id;
7333 	struct got_object_id *base_commit_idp = NULL;
7334 	char *in_repo_path = NULL, *p;
7335 
7336 	if (status == GOT_STATUS_UNVERSIONED ||
7337 	    status == GOT_STATUS_NO_CHANGE)
7338 		return NULL;
7339 	if (status == GOT_STATUS_NONEXISTENT)
7340 		return got_error_set_errno(ENOENT, relpath);
7341 
7342 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
7343 	if (ie == NULL)
7344 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
7345 
7346 	if (asprintf(&in_repo_path, "%s%s%s", a->worktree->path_prefix,
7347 	    got_path_is_root_dir(a->worktree->path_prefix) ? "" : "/",
7348 	    relpath) == -1)
7349 		return got_error_from_errno("asprintf");
7350 
7351 	if (got_fileindex_entry_has_commit(ie)) {
7352 		memcpy(base_commit_id.sha1, ie->commit_sha1,
7353 		    SHA1_DIGEST_LENGTH);
7354 		base_commit_idp = &base_commit_id;
7355 	}
7356 
7357 	if (status == GOT_STATUS_CONFLICT) {
7358 		err = got_error_path(ie->path, GOT_ERR_STAGE_CONFLICT);
7359 		goto done;
7360 	} else if (status != GOT_STATUS_ADD &&
7361 	    status != GOT_STATUS_MODIFY &&
7362 	    status != GOT_STATUS_DELETE) {
7363 		err = got_error_path(ie->path, GOT_ERR_FILE_STATUS);
7364 		goto done;
7365 	}
7366 
7367 	a->have_changes = 1;
7368 
7369 	p = in_repo_path;
7370 	while (p[0] == '/')
7371 		p++;
7372 	err = check_out_of_date(p, status, staged_status,
7373 	    blob_id, base_commit_idp, a->head_commit_id, a->repo,
7374 	    GOT_ERR_STAGE_OUT_OF_DATE);
7375 done:
7376 	free(in_repo_path);
7377 	return err;
7378 }
7379 
7380 struct stage_path_arg {
7381 	struct got_worktree *worktree;
7382 	struct got_fileindex *fileindex;
7383 	struct got_repository *repo;
7384 	got_worktree_status_cb status_cb;
7385 	void *status_arg;
7386 	got_worktree_patch_cb patch_cb;
7387 	void *patch_arg;
7388 	int staged_something;
7389 	int allow_bad_symlinks;
7390 };
7391 
7392 static const struct got_error *
7393 stage_path(void *arg, unsigned char status,
7394     unsigned char staged_status, const char *relpath,
7395     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
7396     struct got_object_id *commit_id, int dirfd, const char *de_name)
7397 {
7398 	struct stage_path_arg *a = arg;
7399 	const struct got_error *err = NULL;
7400 	struct got_fileindex_entry *ie;
7401 	char *ondisk_path = NULL, *path_content = NULL;
7402 	uint32_t stage;
7403 	struct got_object_id *new_staged_blob_id = NULL;
7404 	struct stat sb;
7405 
7406 	if (status == GOT_STATUS_UNVERSIONED)
7407 		return NULL;
7408 
7409 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
7410 	if (ie == NULL)
7411 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
7412 
7413 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path,
7414 	    relpath)== -1)
7415 		return got_error_from_errno("asprintf");
7416 
7417 	switch (status) {
7418 	case GOT_STATUS_ADD:
7419 	case GOT_STATUS_MODIFY:
7420 		/* XXX could sb.st_mode be passed in by our caller? */
7421 		if (lstat(ondisk_path, &sb) == -1) {
7422 			err = got_error_from_errno2("lstat", ondisk_path);
7423 			break;
7424 		}
7425 		if (a->patch_cb) {
7426 			if (status == GOT_STATUS_ADD) {
7427 				int choice = GOT_PATCH_CHOICE_NONE;
7428 				err = (*a->patch_cb)(&choice, a->patch_arg,
7429 				    status, ie->path, NULL, 1, 1);
7430 				if (err)
7431 					break;
7432 				if (choice != GOT_PATCH_CHOICE_YES)
7433 					break;
7434 			} else {
7435 				err = create_patched_content(&path_content, 0,
7436 				    staged_blob_id ? staged_blob_id : blob_id,
7437 				    ondisk_path, dirfd, de_name, ie->path,
7438 				    a->repo, a->patch_cb, a->patch_arg);
7439 				if (err || path_content == NULL)
7440 					break;
7441 			}
7442 		}
7443 		err = got_object_blob_create(&new_staged_blob_id,
7444 		    path_content ? path_content : ondisk_path, a->repo);
7445 		if (err)
7446 			break;
7447 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
7448 		    SHA1_DIGEST_LENGTH);
7449 		if (status == GOT_STATUS_ADD || staged_status == GOT_STATUS_ADD)
7450 			stage = GOT_FILEIDX_STAGE_ADD;
7451 		else
7452 			stage = GOT_FILEIDX_STAGE_MODIFY;
7453 		got_fileindex_entry_stage_set(ie, stage);
7454 		if (S_ISLNK(sb.st_mode)) {
7455 			int is_bad_symlink = 0;
7456 			if (!a->allow_bad_symlinks) {
7457 				char target_path[PATH_MAX];
7458 				ssize_t target_len;
7459 				target_len = readlink(ondisk_path, target_path,
7460 				    sizeof(target_path));
7461 				if (target_len == -1) {
7462 					err = got_error_from_errno2("readlink",
7463 					    ondisk_path);
7464 					break;
7465 				}
7466 				err = is_bad_symlink_target(&is_bad_symlink,
7467 				    target_path, target_len, ondisk_path,
7468 				    a->worktree->root_path);
7469 				if (err)
7470 					break;
7471 				if (is_bad_symlink) {
7472 					err = got_error_path(ondisk_path,
7473 					    GOT_ERR_BAD_SYMLINK);
7474 					break;
7475 				}
7476 			}
7477 			if (is_bad_symlink)
7478 				got_fileindex_entry_staged_filetype_set(ie,
7479 				    GOT_FILEIDX_MODE_BAD_SYMLINK);
7480 			else
7481 				got_fileindex_entry_staged_filetype_set(ie,
7482 				    GOT_FILEIDX_MODE_SYMLINK);
7483 		} else {
7484 			got_fileindex_entry_staged_filetype_set(ie,
7485 			    GOT_FILEIDX_MODE_REGULAR_FILE);
7486 		}
7487 		a->staged_something = 1;
7488 		if (a->status_cb == NULL)
7489 			break;
7490 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
7491 		    get_staged_status(ie), relpath, blob_id,
7492 		    new_staged_blob_id, NULL, dirfd, de_name);
7493 		break;
7494 	case GOT_STATUS_DELETE:
7495 		if (staged_status == GOT_STATUS_DELETE)
7496 			break;
7497 		if (a->patch_cb) {
7498 			int choice = GOT_PATCH_CHOICE_NONE;
7499 			err = (*a->patch_cb)(&choice, a->patch_arg, status,
7500 			    ie->path, NULL, 1, 1);
7501 			if (err)
7502 				break;
7503 			if (choice == GOT_PATCH_CHOICE_NO)
7504 				break;
7505 			if (choice != GOT_PATCH_CHOICE_YES) {
7506 				err = got_error(GOT_ERR_PATCH_CHOICE);
7507 				break;
7508 			}
7509 		}
7510 		stage = GOT_FILEIDX_STAGE_DELETE;
7511 		got_fileindex_entry_stage_set(ie, stage);
7512 		a->staged_something = 1;
7513 		if (a->status_cb == NULL)
7514 			break;
7515 		err = (*a->status_cb)(a->status_arg, GOT_STATUS_NO_CHANGE,
7516 		    get_staged_status(ie), relpath, NULL, NULL, NULL, dirfd,
7517 		    de_name);
7518 		break;
7519 	case GOT_STATUS_NO_CHANGE:
7520 		break;
7521 	case GOT_STATUS_CONFLICT:
7522 		err = got_error_path(relpath, GOT_ERR_STAGE_CONFLICT);
7523 		break;
7524 	case GOT_STATUS_NONEXISTENT:
7525 		err = got_error_set_errno(ENOENT, relpath);
7526 		break;
7527 	default:
7528 		err = got_error_path(relpath, GOT_ERR_FILE_STATUS);
7529 		break;
7530 	}
7531 
7532 	if (path_content && unlink(path_content) == -1 && err == NULL)
7533 		err = got_error_from_errno2("unlink", path_content);
7534 	free(path_content);
7535 	free(ondisk_path);
7536 	free(new_staged_blob_id);
7537 	return err;
7538 }
7539 
7540 const struct got_error *
7541 got_worktree_stage(struct got_worktree *worktree,
7542     struct got_pathlist_head *paths,
7543     got_worktree_status_cb status_cb, void *status_arg,
7544     got_worktree_patch_cb patch_cb, void *patch_arg,
7545     int allow_bad_symlinks, struct got_repository *repo)
7546 {
7547 	const struct got_error *err = NULL, *sync_err, *unlockerr;
7548 	struct got_pathlist_entry *pe;
7549 	struct got_fileindex *fileindex = NULL;
7550 	char *fileindex_path = NULL;
7551 	struct got_reference *head_ref = NULL;
7552 	struct got_object_id *head_commit_id = NULL;
7553 	struct check_stage_ok_arg oka;
7554 	struct stage_path_arg spa;
7555 
7556 	err = lock_worktree(worktree, LOCK_EX);
7557 	if (err)
7558 		return err;
7559 
7560 	err = got_ref_open(&head_ref, repo,
7561 	    got_worktree_get_head_ref_name(worktree), 0);
7562 	if (err)
7563 		goto done;
7564 	err = got_ref_resolve(&head_commit_id, repo, head_ref);
7565 	if (err)
7566 		goto done;
7567 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
7568 	if (err)
7569 		goto done;
7570 
7571 	/* Check pre-conditions before staging anything. */
7572 	oka.head_commit_id = head_commit_id;
7573 	oka.worktree = worktree;
7574 	oka.fileindex = fileindex;
7575 	oka.repo = repo;
7576 	oka.have_changes = 0;
7577 	TAILQ_FOREACH(pe, paths, entry) {
7578 		err = worktree_status(worktree, pe->path, fileindex, repo,
7579 		    check_stage_ok, &oka, NULL, NULL, 0, 0);
7580 		if (err)
7581 			goto done;
7582 	}
7583 	if (!oka.have_changes) {
7584 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
7585 		goto done;
7586 	}
7587 
7588 	spa.worktree = worktree;
7589 	spa.fileindex = fileindex;
7590 	spa.repo = repo;
7591 	spa.patch_cb = patch_cb;
7592 	spa.patch_arg = patch_arg;
7593 	spa.status_cb = status_cb;
7594 	spa.status_arg = status_arg;
7595 	spa.staged_something = 0;
7596 	spa.allow_bad_symlinks = allow_bad_symlinks;
7597 	TAILQ_FOREACH(pe, paths, entry) {
7598 		err = worktree_status(worktree, pe->path, fileindex, repo,
7599 		    stage_path, &spa, NULL, NULL, 0, 0);
7600 		if (err)
7601 			goto done;
7602 	}
7603 	if (!spa.staged_something) {
7604 		err = got_error(GOT_ERR_STAGE_NO_CHANGE);
7605 		goto done;
7606 	}
7607 
7608 	sync_err = sync_fileindex(fileindex, fileindex_path);
7609 	if (sync_err && err == NULL)
7610 		err = sync_err;
7611 done:
7612 	if (head_ref)
7613 		got_ref_close(head_ref);
7614 	free(head_commit_id);
7615 	free(fileindex_path);
7616 	if (fileindex)
7617 		got_fileindex_free(fileindex);
7618 	unlockerr = lock_worktree(worktree, LOCK_SH);
7619 	if (unlockerr && err == NULL)
7620 		err = unlockerr;
7621 	return err;
7622 }
7623 
7624 struct unstage_path_arg {
7625 	struct got_worktree *worktree;
7626 	struct got_fileindex *fileindex;
7627 	struct got_repository *repo;
7628 	got_worktree_checkout_cb progress_cb;
7629 	void *progress_arg;
7630 	got_worktree_patch_cb patch_cb;
7631 	void *patch_arg;
7632 };
7633 
7634 static const struct got_error *
7635 create_unstaged_content(char **path_unstaged_content,
7636     char **path_new_staged_content, struct got_object_id *blob_id,
7637     struct got_object_id *staged_blob_id, const char *relpath,
7638     struct got_repository *repo,
7639     got_worktree_patch_cb patch_cb, void *patch_arg)
7640 {
7641 	const struct got_error *err, *free_err;
7642 	struct got_blob_object *blob = NULL, *staged_blob = NULL;
7643 	FILE *f1 = NULL, *f2 = NULL, *outfile = NULL, *rejectfile = NULL;
7644 	char *path1 = NULL, *path2 = NULL, *label1 = NULL;
7645 	struct got_diffreg_result *diffreg_result = NULL;
7646 	int line_cur1 = 1, line_cur2 = 1, n = 0, nchunks_used = 0;
7647 	int have_content = 0, have_rejected_content = 0, i = 0, nchanges = 0;
7648 
7649 	*path_unstaged_content = NULL;
7650 	*path_new_staged_content = NULL;
7651 
7652 	err = got_object_id_str(&label1, blob_id);
7653 	if (err)
7654 		return err;
7655 	err = got_object_open_as_blob(&blob, repo, blob_id, 8192);
7656 	if (err)
7657 		goto done;
7658 
7659 	err = got_opentemp_named(&path1, &f1, "got-unstage-blob-base");
7660 	if (err)
7661 		goto done;
7662 
7663 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f1, blob);
7664 	if (err)
7665 		goto done;
7666 
7667 	err = got_object_open_as_blob(&staged_blob, repo, staged_blob_id, 8192);
7668 	if (err)
7669 		goto done;
7670 
7671 	err = got_opentemp_named(&path2, &f2, "got-unstage-blob-staged");
7672 	if (err)
7673 		goto done;
7674 
7675 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, f2, staged_blob);
7676 	if (err)
7677 		goto done;
7678 
7679 	err = got_diff_files(&diffreg_result, f1, label1, f2,
7680 	    path2, 3, 0, 1, NULL);
7681 	if (err)
7682 		goto done;
7683 
7684 	err = got_opentemp_named(path_unstaged_content, &outfile,
7685 	    "got-unstaged-content");
7686 	if (err)
7687 		goto done;
7688 	err = got_opentemp_named(path_new_staged_content, &rejectfile,
7689 	    "got-new-staged-content");
7690 	if (err)
7691 		goto done;
7692 
7693 	if (fseek(f1, 0L, SEEK_SET) == -1) {
7694 		err = got_ferror(f1, GOT_ERR_IO);
7695 		goto done;
7696 	}
7697 	if (fseek(f2, 0L, SEEK_SET) == -1) {
7698 		err = got_ferror(f2, GOT_ERR_IO);
7699 		goto done;
7700 	}
7701 	/* Count the number of actual changes in the diff result. */
7702 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
7703 		struct diff_chunk_context cc = {}; 
7704 		diff_chunk_context_load_change(&cc, &nchunks_used,
7705 		    diffreg_result->result, n, 0);
7706 		nchanges++;
7707 	}
7708 	for (n = 0; n < diffreg_result->result->chunks.len; n += nchunks_used) {
7709 		int choice;
7710 		err = apply_or_reject_change(&choice, &nchunks_used,
7711 		    diffreg_result->result, n, relpath, f1, f2,
7712 		    &line_cur1, &line_cur2,
7713 		    outfile, rejectfile, ++i, nchanges, patch_cb, patch_arg);
7714 		if (err)
7715 			goto done;
7716 		if (choice == GOT_PATCH_CHOICE_YES)
7717 			have_content = 1;
7718 		else
7719 			have_rejected_content = 1;
7720 		if (choice == GOT_PATCH_CHOICE_QUIT)
7721 			break;
7722 	}
7723 	if (have_content || have_rejected_content)
7724 		err = copy_remaining_content(f1, f2, &line_cur1, &line_cur2,
7725 		    outfile, rejectfile);
7726 done:
7727 	free(label1);
7728 	if (blob)
7729 		got_object_blob_close(blob);
7730 	if (staged_blob)
7731 		got_object_blob_close(staged_blob);
7732 	free_err = got_diffreg_result_free(diffreg_result);
7733 	if (free_err && err == NULL)
7734 		err = free_err;
7735 	if (f1 && fclose(f1) == EOF && err == NULL)
7736 		err = got_error_from_errno2("fclose", path1);
7737 	if (f2 && fclose(f2) == EOF && err == NULL)
7738 		err = got_error_from_errno2("fclose", path2);
7739 	if (outfile && fclose(outfile) == EOF && err == NULL)
7740 		err = got_error_from_errno2("fclose", *path_unstaged_content);
7741 	if (rejectfile && fclose(rejectfile) == EOF && err == NULL)
7742 		err = got_error_from_errno2("fclose", *path_new_staged_content);
7743 	if (path1 && unlink(path1) == -1 && err == NULL)
7744 		err = got_error_from_errno2("unlink", path1);
7745 	if (path2 && unlink(path2) == -1 && err == NULL)
7746 		err = got_error_from_errno2("unlink", path2);
7747 	if (err || !have_content) {
7748 		if (*path_unstaged_content &&
7749 		    unlink(*path_unstaged_content) == -1 && err == NULL)
7750 			err = got_error_from_errno2("unlink",
7751 			    *path_unstaged_content);
7752 		free(*path_unstaged_content);
7753 		*path_unstaged_content = NULL;
7754 	}
7755 	if (err || !have_content || !have_rejected_content) {
7756 		if (*path_new_staged_content &&
7757 		    unlink(*path_new_staged_content) == -1 && err == NULL)
7758 			err = got_error_from_errno2("unlink",
7759 			    *path_new_staged_content);
7760 		free(*path_new_staged_content);
7761 		*path_new_staged_content = NULL;
7762 	}
7763 	free(path1);
7764 	free(path2);
7765 	return err;
7766 }
7767 
7768 static const struct got_error *
7769 unstage_hunks(struct got_object_id *staged_blob_id,
7770     struct got_blob_object *blob_base,
7771     struct got_object_id *blob_id, struct got_fileindex_entry *ie,
7772     const char *ondisk_path, const char *label_orig,
7773     struct got_worktree *worktree, struct got_repository *repo,
7774     got_worktree_patch_cb patch_cb, void *patch_arg,
7775     got_worktree_checkout_cb progress_cb, void *progress_arg)
7776 {
7777 	const struct got_error *err = NULL;
7778 	char *path_unstaged_content = NULL;
7779 	char *path_new_staged_content = NULL;
7780 	char *parent = NULL, *base_path = NULL;
7781 	char *blob_base_path = NULL;
7782 	struct got_object_id *new_staged_blob_id = NULL;
7783 	FILE *f = NULL, *f_base = NULL, *f_deriv2 = NULL;
7784 	struct stat sb;
7785 
7786 	err = create_unstaged_content(&path_unstaged_content,
7787 	    &path_new_staged_content, blob_id, staged_blob_id,
7788 	    ie->path, repo, patch_cb, patch_arg);
7789 	if (err)
7790 		return err;
7791 
7792 	if (path_unstaged_content == NULL)
7793 		return NULL;
7794 
7795 	if (path_new_staged_content) {
7796 		err = got_object_blob_create(&new_staged_blob_id,
7797 		    path_new_staged_content, repo);
7798 		if (err)
7799 			goto done;
7800 	}
7801 
7802 	f = fopen(path_unstaged_content, "r");
7803 	if (f == NULL) {
7804 		err = got_error_from_errno2("fopen",
7805 		    path_unstaged_content);
7806 		goto done;
7807 	}
7808 	if (fstat(fileno(f), &sb) == -1) {
7809 		err = got_error_from_errno2("fstat", path_unstaged_content);
7810 		goto done;
7811 	}
7812 	if (got_fileindex_entry_staged_filetype_get(ie) ==
7813 	    GOT_FILEIDX_MODE_SYMLINK && sb.st_size < PATH_MAX) {
7814 		char link_target[PATH_MAX];
7815 		size_t r;
7816 		r = fread(link_target, 1, sizeof(link_target), f);
7817 		if (r == 0 && ferror(f)) {
7818 			err = got_error_from_errno("fread");
7819 			goto done;
7820 		}
7821 		if (r >= sizeof(link_target)) { /* should not happen */
7822 			err = got_error(GOT_ERR_NO_SPACE);
7823 			goto done;
7824 		}
7825 		link_target[r] = '\0';
7826 		err = merge_symlink(worktree, blob_base,
7827 		    ondisk_path, ie->path, label_orig, link_target,
7828 		    worktree->base_commit_id, repo, progress_cb,
7829 		    progress_arg);
7830 	} else {
7831 		int local_changes_subsumed;
7832 
7833 		err = got_path_dirname(&parent, ondisk_path);
7834 		if (err)
7835 			return err;
7836 
7837 		if (asprintf(&base_path, "%s/got-unstage-blob-orig",
7838 		    parent) == -1) {
7839 			err = got_error_from_errno("asprintf");
7840 			base_path = NULL;
7841 			goto done;
7842 		}
7843 
7844 		err = got_opentemp_named(&blob_base_path, &f_base, base_path);
7845 		if (err)
7846 			goto done;
7847 		err = got_object_blob_dump_to_file(NULL, NULL, NULL, f_base,
7848 		    blob_base);
7849 		if (err)
7850 			goto done;
7851 
7852 		/* 
7853 		 * In order the run a 3-way merge with a symlink we copy the symlink's
7854 		 * target path into a temporary file and use that file with diff3.
7855 		 */
7856 		if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
7857 			err = dump_symlink_target_path_to_file(&f_deriv2,
7858 			    ondisk_path);
7859 			if (err)
7860 				goto done;
7861 		} else {
7862 			int fd;
7863 			fd = open(ondisk_path, O_RDONLY | O_NOFOLLOW);
7864 			if (fd == -1) {
7865 				err = got_error_from_errno2("open", ondisk_path);
7866 				goto done;
7867 			}
7868 			f_deriv2 = fdopen(fd, "r");
7869 			if (f_deriv2 == NULL) {
7870 				err = got_error_from_errno2("fdopen", ondisk_path);
7871 				close(fd);
7872 				goto done;
7873 			}
7874 		}
7875 
7876 		err = merge_file(&local_changes_subsumed, worktree,
7877 		    f_base, f, f_deriv2, ondisk_path, ie->path,
7878 		    got_fileindex_perms_to_st(ie),
7879 		    label_orig, "unstaged", NULL, GOT_DIFF_ALGORITHM_MYERS,
7880 		    repo, progress_cb, progress_arg);
7881 	}
7882 	if (err)
7883 		goto done;
7884 
7885 	if (new_staged_blob_id) {
7886 		memcpy(ie->staged_blob_sha1, new_staged_blob_id->sha1,
7887 		    SHA1_DIGEST_LENGTH);
7888 	} else {
7889 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
7890 		got_fileindex_entry_staged_filetype_set(ie, 0);
7891 	}
7892 done:
7893 	free(new_staged_blob_id);
7894 	if (path_unstaged_content &&
7895 	    unlink(path_unstaged_content) == -1 && err == NULL)
7896 		err = got_error_from_errno2("unlink", path_unstaged_content);
7897 	if (path_new_staged_content &&
7898 	    unlink(path_new_staged_content) == -1 && err == NULL)
7899 		err = got_error_from_errno2("unlink", path_new_staged_content);
7900 	if (blob_base_path && unlink(blob_base_path) == -1 && err == NULL)
7901 		err = got_error_from_errno2("unlink", blob_base_path);
7902 	if (f_base && fclose(f_base) == EOF && err == NULL)
7903 		err = got_error_from_errno2("fclose", path_unstaged_content);
7904 	if (f && fclose(f) == EOF && err == NULL)
7905 		err = got_error_from_errno2("fclose", path_unstaged_content);
7906 	if (f_deriv2 && fclose(f_deriv2) == EOF && err == NULL)
7907 		err = got_error_from_errno2("fclose", ondisk_path);
7908 	free(path_unstaged_content);
7909 	free(path_new_staged_content);
7910 	free(blob_base_path);
7911 	free(parent);
7912 	free(base_path);
7913 	return err;
7914 }
7915 
7916 static const struct got_error *
7917 unstage_path(void *arg, unsigned char status,
7918     unsigned char staged_status, const char *relpath,
7919     struct got_object_id *blob_id, struct got_object_id *staged_blob_id,
7920     struct got_object_id *commit_id, int dirfd, const char *de_name)
7921 {
7922 	const struct got_error *err = NULL;
7923 	struct unstage_path_arg *a = arg;
7924 	struct got_fileindex_entry *ie;
7925 	struct got_blob_object *blob_base = NULL, *blob_staged = NULL;
7926 	char *ondisk_path = NULL;
7927 	char *id_str = NULL, *label_orig = NULL;
7928 	int local_changes_subsumed;
7929 	struct stat sb;
7930 
7931 	if (staged_status != GOT_STATUS_ADD &&
7932 	    staged_status != GOT_STATUS_MODIFY &&
7933 	    staged_status != GOT_STATUS_DELETE)
7934 		return NULL;
7935 
7936 	ie = got_fileindex_entry_get(a->fileindex, relpath, strlen(relpath));
7937 	if (ie == NULL)
7938 		return got_error_path(relpath, GOT_ERR_FILE_STATUS);
7939 
7940 	if (asprintf(&ondisk_path, "%s/%s", a->worktree->root_path, relpath)
7941 	    == -1)
7942 		return got_error_from_errno("asprintf");
7943 
7944 	err = got_object_id_str(&id_str,
7945 	    commit_id ? commit_id : a->worktree->base_commit_id);
7946 	if (err)
7947 		goto done;
7948 	if (asprintf(&label_orig, "%s: commit %s", GOT_MERGE_LABEL_BASE,
7949 	    id_str) == -1) {
7950 		err = got_error_from_errno("asprintf");
7951 		goto done;
7952 	}
7953 
7954 	switch (staged_status) {
7955 	case GOT_STATUS_MODIFY:
7956 		err = got_object_open_as_blob(&blob_base, a->repo,
7957 		    blob_id, 8192);
7958 		if (err)
7959 			break;
7960 		/* fall through */
7961 	case GOT_STATUS_ADD:
7962 		if (a->patch_cb) {
7963 			if (staged_status == GOT_STATUS_ADD) {
7964 				int choice = GOT_PATCH_CHOICE_NONE;
7965 				err = (*a->patch_cb)(&choice, a->patch_arg,
7966 				    staged_status, ie->path, NULL, 1, 1);
7967 				if (err)
7968 					break;
7969 				if (choice != GOT_PATCH_CHOICE_YES)
7970 					break;
7971 			} else {
7972 				err = unstage_hunks(staged_blob_id,
7973 				    blob_base, blob_id, ie, ondisk_path,
7974 				    label_orig, a->worktree, a->repo,
7975 				    a->patch_cb, a->patch_arg,
7976 				    a->progress_cb, a->progress_arg);
7977 				break; /* Done with this file. */
7978 			}
7979 		}
7980 		err = got_object_open_as_blob(&blob_staged, a->repo,
7981 		    staged_blob_id, 8192);
7982 		if (err)
7983 			break;
7984 		switch (got_fileindex_entry_staged_filetype_get(ie)) {
7985 		case GOT_FILEIDX_MODE_BAD_SYMLINK:
7986 		case GOT_FILEIDX_MODE_REGULAR_FILE:
7987 			err = merge_blob(&local_changes_subsumed, a->worktree,
7988 			    blob_base, ondisk_path, relpath,
7989 			    got_fileindex_perms_to_st(ie), label_orig,
7990 			    blob_staged, commit_id ? commit_id :
7991 			    a->worktree->base_commit_id, a->repo,
7992 			    a->progress_cb, a->progress_arg);
7993 			break;
7994 		case GOT_FILEIDX_MODE_SYMLINK:
7995 			if (S_ISLNK(got_fileindex_perms_to_st(ie))) {
7996 				char *staged_target;
7997 				err = got_object_blob_read_to_str(
7998 				    &staged_target, blob_staged);
7999 				if (err)
8000 					goto done;
8001 				err = merge_symlink(a->worktree, blob_base,
8002 				    ondisk_path, relpath, label_orig,
8003 				    staged_target, commit_id ? commit_id :
8004 				    a->worktree->base_commit_id,
8005 				    a->repo, a->progress_cb, a->progress_arg);
8006 				free(staged_target);
8007 			} else {
8008 				err = merge_blob(&local_changes_subsumed,
8009 				    a->worktree, blob_base, ondisk_path,
8010 				    relpath, got_fileindex_perms_to_st(ie),
8011 				    label_orig, blob_staged,
8012 				    commit_id ? commit_id :
8013 				    a->worktree->base_commit_id, a->repo,
8014 				    a->progress_cb, a->progress_arg);
8015 			}
8016 			break;
8017 		default:
8018 			err = got_error_path(relpath, GOT_ERR_BAD_FILETYPE);
8019 			break;
8020 		}
8021 		if (err == NULL) {
8022 			got_fileindex_entry_stage_set(ie,
8023 			    GOT_FILEIDX_STAGE_NONE);
8024 			got_fileindex_entry_staged_filetype_set(ie, 0);
8025 		}
8026 		break;
8027 	case GOT_STATUS_DELETE:
8028 		if (a->patch_cb) {
8029 			int choice = GOT_PATCH_CHOICE_NONE;
8030 			err = (*a->patch_cb)(&choice, a->patch_arg,
8031 			    staged_status, ie->path, NULL, 1, 1);
8032 			if (err)
8033 				break;
8034 			if (choice == GOT_PATCH_CHOICE_NO)
8035 				break;
8036 			if (choice != GOT_PATCH_CHOICE_YES) {
8037 				err = got_error(GOT_ERR_PATCH_CHOICE);
8038 				break;
8039 			}
8040 		}
8041 		got_fileindex_entry_stage_set(ie, GOT_FILEIDX_STAGE_NONE);
8042 		got_fileindex_entry_staged_filetype_set(ie, 0);
8043 		err = get_file_status(&status, &sb, ie, ondisk_path,
8044 		    dirfd, de_name, a->repo);
8045 		if (err)
8046 			break;
8047 		err = (*a->progress_cb)(a->progress_arg, status, relpath);
8048 		break;
8049 	}
8050 done:
8051 	free(ondisk_path);
8052 	if (blob_base)
8053 		got_object_blob_close(blob_base);
8054 	if (blob_staged)
8055 		got_object_blob_close(blob_staged);
8056 	free(id_str);
8057 	free(label_orig);
8058 	return err;
8059 }
8060 
8061 const struct got_error *
8062 got_worktree_unstage(struct got_worktree *worktree,
8063     struct got_pathlist_head *paths,
8064     got_worktree_checkout_cb progress_cb, void *progress_arg,
8065     got_worktree_patch_cb patch_cb, void *patch_arg,
8066     struct got_repository *repo)
8067 {
8068 	const struct got_error *err = NULL, *sync_err, *unlockerr;
8069 	struct got_pathlist_entry *pe;
8070 	struct got_fileindex *fileindex = NULL;
8071 	char *fileindex_path = NULL;
8072 	struct unstage_path_arg upa;
8073 
8074 	err = lock_worktree(worktree, LOCK_EX);
8075 	if (err)
8076 		return err;
8077 
8078 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
8079 	if (err)
8080 		goto done;
8081 
8082 	upa.worktree = worktree;
8083 	upa.fileindex = fileindex;
8084 	upa.repo = repo;
8085 	upa.progress_cb = progress_cb;
8086 	upa.progress_arg = progress_arg;
8087 	upa.patch_cb = patch_cb;
8088 	upa.patch_arg = patch_arg;
8089 	TAILQ_FOREACH(pe, paths, entry) {
8090 		err = worktree_status(worktree, pe->path, fileindex, repo,
8091 		    unstage_path, &upa, NULL, NULL, 0, 0);
8092 		if (err)
8093 			goto done;
8094 	}
8095 
8096 	sync_err = sync_fileindex(fileindex, fileindex_path);
8097 	if (sync_err && err == NULL)
8098 		err = sync_err;
8099 done:
8100 	free(fileindex_path);
8101 	if (fileindex)
8102 		got_fileindex_free(fileindex);
8103 	unlockerr = lock_worktree(worktree, LOCK_SH);
8104 	if (unlockerr && err == NULL)
8105 		err = unlockerr;
8106 	return err;
8107 }
8108 
8109 struct report_file_info_arg {
8110 	struct got_worktree *worktree;
8111 	got_worktree_path_info_cb info_cb;
8112 	void *info_arg;
8113 	struct got_pathlist_head *paths;
8114 	got_cancel_cb cancel_cb;
8115 	void *cancel_arg;
8116 };
8117 
8118 static const struct got_error *
8119 report_file_info(void *arg, struct got_fileindex_entry *ie)
8120 {
8121 	struct report_file_info_arg *a = arg;
8122 	struct got_pathlist_entry *pe;
8123 	struct got_object_id blob_id, staged_blob_id, commit_id;
8124 	struct got_object_id *blob_idp = NULL, *staged_blob_idp = NULL;
8125 	struct got_object_id *commit_idp = NULL;
8126 	int stage;
8127 
8128 	if (a->cancel_cb && a->cancel_cb(a->cancel_arg))
8129 		return got_error(GOT_ERR_CANCELLED);
8130 
8131 	TAILQ_FOREACH(pe, a->paths, entry) {
8132 		if (pe->path_len == 0 || strcmp(pe->path, ie->path) == 0 ||
8133 		    got_path_is_child(ie->path, pe->path, pe->path_len))
8134 			break;
8135 	}
8136 	if (pe == NULL) /* not found */
8137 		return NULL;
8138 
8139 	if (got_fileindex_entry_has_blob(ie)) {
8140 		memcpy(blob_id.sha1, ie->blob_sha1, SHA1_DIGEST_LENGTH);
8141 		blob_idp = &blob_id;
8142 	}
8143 	stage = got_fileindex_entry_stage_get(ie);
8144 	if (stage == GOT_FILEIDX_STAGE_MODIFY ||
8145 	    stage == GOT_FILEIDX_STAGE_ADD) {
8146 		memcpy(staged_blob_id.sha1, ie->staged_blob_sha1,
8147 		    SHA1_DIGEST_LENGTH);
8148 		staged_blob_idp = &staged_blob_id;
8149 	}
8150 
8151 	if (got_fileindex_entry_has_commit(ie)) {
8152 		memcpy(commit_id.sha1, ie->commit_sha1, SHA1_DIGEST_LENGTH);
8153 		commit_idp = &commit_id;
8154 	}
8155 
8156 	return a->info_cb(a->info_arg, ie->path, got_fileindex_perms_to_st(ie),
8157 	    (time_t)ie->mtime_sec, blob_idp, staged_blob_idp, commit_idp);
8158 }
8159 
8160 const struct got_error *
8161 got_worktree_path_info(struct got_worktree *worktree,
8162     struct got_pathlist_head *paths,
8163     got_worktree_path_info_cb info_cb, void *info_arg,
8164     got_cancel_cb cancel_cb, void *cancel_arg)
8165 
8166 {
8167 	const struct got_error *err = NULL, *unlockerr;
8168 	struct got_fileindex *fileindex = NULL;
8169 	char *fileindex_path = NULL;
8170 	struct report_file_info_arg arg;
8171 
8172 	err = lock_worktree(worktree, LOCK_SH);
8173 	if (err)
8174 		return err;
8175 
8176 	err = open_fileindex(&fileindex, &fileindex_path, worktree);
8177 	if (err)
8178 		goto done;
8179 
8180 	arg.worktree = worktree;
8181 	arg.info_cb = info_cb;
8182 	arg.info_arg = info_arg;
8183 	arg.paths = paths;
8184 	arg.cancel_cb = cancel_cb;
8185 	arg.cancel_arg = cancel_arg;
8186 	err = got_fileindex_for_each_entry_safe(fileindex, report_file_info,
8187 	    &arg);
8188 done:
8189 	free(fileindex_path);
8190 	if (fileindex)
8191 		got_fileindex_free(fileindex);
8192 	unlockerr = lock_worktree(worktree, LOCK_UN);
8193 	if (unlockerr && err == NULL)
8194 		err = unlockerr;
8195 	return err;
8196 }