refs.c: add err arguments to reflog functions
[git/git.git] / builtin / checkout.c
1 #include "builtin.h"
2 #include "lockfile.h"
3 #include "parse-options.h"
4 #include "refs.h"
5 #include "commit.h"
6 #include "tree.h"
7 #include "tree-walk.h"
8 #include "cache-tree.h"
9 #include "unpack-trees.h"
10 #include "dir.h"
11 #include "run-command.h"
12 #include "merge-recursive.h"
13 #include "branch.h"
14 #include "diff.h"
15 #include "revision.h"
16 #include "remote.h"
17 #include "blob.h"
18 #include "xdiff-interface.h"
19 #include "ll-merge.h"
20 #include "resolve-undo.h"
21 #include "submodule.h"
22 #include "argv-array.h"
23 #include "sigchain.h"
24
25 static const char * const checkout_usage[] = {
26 N_("git checkout [<options>] <branch>"),
27 N_("git checkout [<options>] [<branch>] -- <file>..."),
28 NULL,
29 };
30
31 struct checkout_opts {
32 int patch_mode;
33 int quiet;
34 int merge;
35 int force;
36 int force_detach;
37 int writeout_stage;
38 int overwrite_ignore;
39 int ignore_skipworktree;
40 int ignore_other_worktrees;
41
42 const char *new_branch;
43 const char *new_branch_force;
44 const char *new_orphan_branch;
45 int new_branch_log;
46 enum branch_track track;
47 struct diff_options diff_options;
48
49 int branch_exists;
50 const char *prefix;
51 struct pathspec pathspec;
52 struct tree *source_tree;
53
54 const char *new_worktree;
55 const char **saved_argv;
56 int new_worktree_mode;
57 };
58
59 static int post_checkout_hook(struct commit *old, struct commit *new,
60 int changed)
61 {
62 return run_hook_le(NULL, "post-checkout",
63 sha1_to_hex(old ? old->object.sha1 : null_sha1),
64 sha1_to_hex(new ? new->object.sha1 : null_sha1),
65 changed ? "1" : "0", NULL);
66 /* "new" can be NULL when checking out from the index before
67 a commit exists. */
68
69 }
70
71 static int update_some(const unsigned char *sha1, struct strbuf *base,
72 const char *pathname, unsigned mode, int stage, void *context)
73 {
74 int len;
75 struct cache_entry *ce;
76 int pos;
77
78 if (S_ISDIR(mode))
79 return READ_TREE_RECURSIVE;
80
81 len = base->len + strlen(pathname);
82 ce = xcalloc(1, cache_entry_size(len));
83 hashcpy(ce->sha1, sha1);
84 memcpy(ce->name, base->buf, base->len);
85 memcpy(ce->name + base->len, pathname, len - base->len);
86 ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
87 ce->ce_namelen = len;
88 ce->ce_mode = create_ce_mode(mode);
89
90 /*
91 * If the entry is the same as the current index, we can leave the old
92 * entry in place. Whether it is UPTODATE or not, checkout_entry will
93 * do the right thing.
94 */
95 pos = cache_name_pos(ce->name, ce->ce_namelen);
96 if (pos >= 0) {
97 struct cache_entry *old = active_cache[pos];
98 if (ce->ce_mode == old->ce_mode &&
99 !hashcmp(ce->sha1, old->sha1)) {
100 old->ce_flags |= CE_UPDATE;
101 free(ce);
102 return 0;
103 }
104 }
105
106 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
107 return 0;
108 }
109
110 static int read_tree_some(struct tree *tree, const struct pathspec *pathspec)
111 {
112 read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
113
114 /* update the index with the given tree's info
115 * for all args, expanding wildcards, and exit
116 * with any non-zero return code.
117 */
118 return 0;
119 }
120
121 static int skip_same_name(const struct cache_entry *ce, int pos)
122 {
123 while (++pos < active_nr &&
124 !strcmp(active_cache[pos]->name, ce->name))
125 ; /* skip */
126 return pos;
127 }
128
129 static int check_stage(int stage, const struct cache_entry *ce, int pos)
130 {
131 while (pos < active_nr &&
132 !strcmp(active_cache[pos]->name, ce->name)) {
133 if (ce_stage(active_cache[pos]) == stage)
134 return 0;
135 pos++;
136 }
137 if (stage == 2)
138 return error(_("path '%s' does not have our version"), ce->name);
139 else
140 return error(_("path '%s' does not have their version"), ce->name);
141 }
142
143 static int check_stages(unsigned stages, const struct cache_entry *ce, int pos)
144 {
145 unsigned seen = 0;
146 const char *name = ce->name;
147
148 while (pos < active_nr) {
149 ce = active_cache[pos];
150 if (strcmp(name, ce->name))
151 break;
152 seen |= (1 << ce_stage(ce));
153 pos++;
154 }
155 if ((stages & seen) != stages)
156 return error(_("path '%s' does not have all necessary versions"),
157 name);
158 return 0;
159 }
160
161 static int checkout_stage(int stage, struct cache_entry *ce, int pos,
162 struct checkout *state)
163 {
164 while (pos < active_nr &&
165 !strcmp(active_cache[pos]->name, ce->name)) {
166 if (ce_stage(active_cache[pos]) == stage)
167 return checkout_entry(active_cache[pos], state, NULL);
168 pos++;
169 }
170 if (stage == 2)
171 return error(_("path '%s' does not have our version"), ce->name);
172 else
173 return error(_("path '%s' does not have their version"), ce->name);
174 }
175
176 static int checkout_merged(int pos, struct checkout *state)
177 {
178 struct cache_entry *ce = active_cache[pos];
179 const char *path = ce->name;
180 mmfile_t ancestor, ours, theirs;
181 int status;
182 unsigned char sha1[20];
183 mmbuffer_t result_buf;
184 unsigned char threeway[3][20];
185 unsigned mode = 0;
186
187 memset(threeway, 0, sizeof(threeway));
188 while (pos < active_nr) {
189 int stage;
190 stage = ce_stage(ce);
191 if (!stage || strcmp(path, ce->name))
192 break;
193 hashcpy(threeway[stage - 1], ce->sha1);
194 if (stage == 2)
195 mode = create_ce_mode(ce->ce_mode);
196 pos++;
197 ce = active_cache[pos];
198 }
199 if (is_null_sha1(threeway[1]) || is_null_sha1(threeway[2]))
200 return error(_("path '%s' does not have necessary versions"), path);
201
202 read_mmblob(&ancestor, threeway[0]);
203 read_mmblob(&ours, threeway[1]);
204 read_mmblob(&theirs, threeway[2]);
205
206 /*
207 * NEEDSWORK: re-create conflicts from merges with
208 * merge.renormalize set, too
209 */
210 status = ll_merge(&result_buf, path, &ancestor, "base",
211 &ours, "ours", &theirs, "theirs", NULL);
212 free(ancestor.ptr);
213 free(ours.ptr);
214 free(theirs.ptr);
215 if (status < 0 || !result_buf.ptr) {
216 free(result_buf.ptr);
217 return error(_("path '%s': cannot merge"), path);
218 }
219
220 /*
221 * NEEDSWORK:
222 * There is absolutely no reason to write this as a blob object
223 * and create a phony cache entry just to leak. This hack is
224 * primarily to get to the write_entry() machinery that massages
225 * the contents to work-tree format and writes out which only
226 * allows it for a cache entry. The code in write_entry() needs
227 * to be refactored to allow us to feed a <buffer, size, mode>
228 * instead of a cache entry. Such a refactoring would help
229 * merge_recursive as well (it also writes the merge result to the
230 * object database even when it may contain conflicts).
231 */
232 if (write_sha1_file(result_buf.ptr, result_buf.size,
233 blob_type, sha1))
234 die(_("Unable to add merge result for '%s'"), path);
235 ce = make_cache_entry(mode, sha1, path, 2, 0);
236 if (!ce)
237 die(_("make_cache_entry failed for path '%s'"), path);
238 status = checkout_entry(ce, state, NULL);
239 return status;
240 }
241
242 static int checkout_paths(const struct checkout_opts *opts,
243 const char *revision)
244 {
245 int pos;
246 struct checkout state;
247 static char *ps_matched;
248 unsigned char rev[20];
249 int flag;
250 struct commit *head;
251 int errs = 0;
252 struct lock_file *lock_file;
253
254 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
255 die(_("'%s' cannot be used with updating paths"), "--track");
256
257 if (opts->new_branch_log)
258 die(_("'%s' cannot be used with updating paths"), "-l");
259
260 if (opts->force && opts->patch_mode)
261 die(_("'%s' cannot be used with updating paths"), "-f");
262
263 if (opts->force_detach)
264 die(_("'%s' cannot be used with updating paths"), "--detach");
265
266 if (opts->merge && opts->patch_mode)
267 die(_("'%s' cannot be used with %s"), "--merge", "--patch");
268
269 if (opts->force && opts->merge)
270 die(_("'%s' cannot be used with %s"), "-f", "-m");
271
272 if (opts->new_branch)
273 die(_("Cannot update paths and switch to branch '%s' at the same time."),
274 opts->new_branch);
275
276 if (opts->new_worktree)
277 die(_("'%s' cannot be used with updating paths"), "--to");
278
279 if (opts->patch_mode)
280 return run_add_interactive(revision, "--patch=checkout",
281 &opts->pathspec);
282
283 lock_file = xcalloc(1, sizeof(struct lock_file));
284
285 hold_locked_index(lock_file, 1);
286 if (read_cache_preload(&opts->pathspec) < 0)
287 return error(_("corrupt index file"));
288
289 if (opts->source_tree)
290 read_tree_some(opts->source_tree, &opts->pathspec);
291
292 ps_matched = xcalloc(1, opts->pathspec.nr);
293
294 /*
295 * Make sure all pathspecs participated in locating the paths
296 * to be checked out.
297 */
298 for (pos = 0; pos < active_nr; pos++) {
299 struct cache_entry *ce = active_cache[pos];
300 ce->ce_flags &= ~CE_MATCHED;
301 if (!opts->ignore_skipworktree && ce_skip_worktree(ce))
302 continue;
303 if (opts->source_tree && !(ce->ce_flags & CE_UPDATE))
304 /*
305 * "git checkout tree-ish -- path", but this entry
306 * is in the original index; it will not be checked
307 * out to the working tree and it does not matter
308 * if pathspec matched this entry. We will not do
309 * anything to this entry at all.
310 */
311 continue;
312 /*
313 * Either this entry came from the tree-ish we are
314 * checking the paths out of, or we are checking out
315 * of the index.
316 *
317 * If it comes from the tree-ish, we already know it
318 * matches the pathspec and could just stamp
319 * CE_MATCHED to it from update_some(). But we still
320 * need ps_matched and read_tree_recursive (and
321 * eventually tree_entry_interesting) cannot fill
322 * ps_matched yet. Once it can, we can avoid calling
323 * match_pathspec() for _all_ entries when
324 * opts->source_tree != NULL.
325 */
326 if (ce_path_match(ce, &opts->pathspec, ps_matched))
327 ce->ce_flags |= CE_MATCHED;
328 }
329
330 if (report_path_error(ps_matched, &opts->pathspec, opts->prefix)) {
331 free(ps_matched);
332 return 1;
333 }
334 free(ps_matched);
335
336 /* "checkout -m path" to recreate conflicted state */
337 if (opts->merge)
338 unmerge_marked_index(&the_index);
339
340 /* Any unmerged paths? */
341 for (pos = 0; pos < active_nr; pos++) {
342 const struct cache_entry *ce = active_cache[pos];
343 if (ce->ce_flags & CE_MATCHED) {
344 if (!ce_stage(ce))
345 continue;
346 if (opts->force) {
347 warning(_("path '%s' is unmerged"), ce->name);
348 } else if (opts->writeout_stage) {
349 errs |= check_stage(opts->writeout_stage, ce, pos);
350 } else if (opts->merge) {
351 errs |= check_stages((1<<2) | (1<<3), ce, pos);
352 } else {
353 errs = 1;
354 error(_("path '%s' is unmerged"), ce->name);
355 }
356 pos = skip_same_name(ce, pos) - 1;
357 }
358 }
359 if (errs)
360 return 1;
361
362 /* Now we are committed to check them out */
363 memset(&state, 0, sizeof(state));
364 state.force = 1;
365 state.refresh_cache = 1;
366 state.istate = &the_index;
367 for (pos = 0; pos < active_nr; pos++) {
368 struct cache_entry *ce = active_cache[pos];
369 if (ce->ce_flags & CE_MATCHED) {
370 if (!ce_stage(ce)) {
371 errs |= checkout_entry(ce, &state, NULL);
372 continue;
373 }
374 if (opts->writeout_stage)
375 errs |= checkout_stage(opts->writeout_stage, ce, pos, &state);
376 else if (opts->merge)
377 errs |= checkout_merged(pos, &state);
378 pos = skip_same_name(ce, pos) - 1;
379 }
380 }
381
382 if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
383 die(_("unable to write new index file"));
384
385 read_ref_full("HEAD", 0, rev, &flag);
386 head = lookup_commit_reference_gently(rev, 1);
387
388 errs |= post_checkout_hook(head, head, 0);
389 return errs;
390 }
391
392 static void show_local_changes(struct object *head,
393 const struct diff_options *opts)
394 {
395 struct rev_info rev;
396 /* I think we want full paths, even if we're in a subdirectory. */
397 init_revisions(&rev, NULL);
398 rev.diffopt.flags = opts->flags;
399 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
400 diff_setup_done(&rev.diffopt);
401 add_pending_object(&rev, head, NULL);
402 run_diff_index(&rev, 0);
403 }
404
405 static void describe_detached_head(const char *msg, struct commit *commit)
406 {
407 struct strbuf sb = STRBUF_INIT;
408 if (!parse_commit(commit))
409 pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
410 fprintf(stderr, "%s %s... %s\n", msg,
411 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
412 strbuf_release(&sb);
413 }
414
415 static int reset_tree(struct tree *tree, const struct checkout_opts *o,
416 int worktree, int *writeout_error)
417 {
418 struct unpack_trees_options opts;
419 struct tree_desc tree_desc;
420
421 memset(&opts, 0, sizeof(opts));
422 opts.head_idx = -1;
423 opts.update = worktree;
424 opts.skip_unmerged = !worktree;
425 opts.reset = 1;
426 opts.merge = 1;
427 opts.fn = oneway_merge;
428 opts.verbose_update = !o->quiet && isatty(2);
429 opts.src_index = &the_index;
430 opts.dst_index = &the_index;
431 parse_tree(tree);
432 init_tree_desc(&tree_desc, tree->buffer, tree->size);
433 switch (unpack_trees(1, &tree_desc, &opts)) {
434 case -2:
435 *writeout_error = 1;
436 /*
437 * We return 0 nevertheless, as the index is all right
438 * and more importantly we have made best efforts to
439 * update paths in the work tree, and we cannot revert
440 * them.
441 */
442 case 0:
443 return 0;
444 default:
445 return 128;
446 }
447 }
448
449 struct branch_info {
450 const char *name; /* The short name used */
451 const char *path; /* The full name of a real branch */
452 struct commit *commit; /* The named commit */
453 /*
454 * if not null the branch is detached because it's already
455 * checked out in this checkout
456 */
457 char *checkout;
458 };
459
460 static void setup_branch_path(struct branch_info *branch)
461 {
462 struct strbuf buf = STRBUF_INIT;
463
464 strbuf_branchname(&buf, branch->name);
465 if (strcmp(buf.buf, branch->name))
466 branch->name = xstrdup(buf.buf);
467 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
468 branch->path = strbuf_detach(&buf, NULL);
469 }
470
471 static int merge_working_tree(const struct checkout_opts *opts,
472 struct branch_info *old,
473 struct branch_info *new,
474 int *writeout_error)
475 {
476 int ret;
477 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
478
479 hold_locked_index(lock_file, 1);
480 if (read_cache_preload(NULL) < 0)
481 return error(_("corrupt index file"));
482
483 resolve_undo_clear();
484 if (opts->force) {
485 ret = reset_tree(new->commit->tree, opts, 1, writeout_error);
486 if (ret)
487 return ret;
488 } else {
489 struct tree_desc trees[2];
490 struct tree *tree;
491 struct unpack_trees_options topts;
492
493 memset(&topts, 0, sizeof(topts));
494 topts.head_idx = -1;
495 topts.src_index = &the_index;
496 topts.dst_index = &the_index;
497
498 setup_unpack_trees_porcelain(&topts, "checkout");
499
500 refresh_cache(REFRESH_QUIET);
501
502 if (unmerged_cache()) {
503 error(_("you need to resolve your current index first"));
504 return 1;
505 }
506
507 /* 2-way merge to the new branch */
508 topts.initial_checkout = is_cache_unborn();
509 topts.update = 1;
510 topts.merge = 1;
511 topts.gently = opts->merge && old->commit;
512 topts.verbose_update = !opts->quiet && isatty(2);
513 topts.fn = twoway_merge;
514 if (opts->overwrite_ignore) {
515 topts.dir = xcalloc(1, sizeof(*topts.dir));
516 topts.dir->flags |= DIR_SHOW_IGNORED;
517 setup_standard_excludes(topts.dir);
518 }
519 tree = parse_tree_indirect(old->commit && !opts->new_worktree_mode ?
520 old->commit->object.sha1 :
521 EMPTY_TREE_SHA1_BIN);
522 init_tree_desc(&trees[0], tree->buffer, tree->size);
523 tree = parse_tree_indirect(new->commit->object.sha1);
524 init_tree_desc(&trees[1], tree->buffer, tree->size);
525
526 ret = unpack_trees(2, trees, &topts);
527 if (ret == -1) {
528 /*
529 * Unpack couldn't do a trivial merge; either
530 * give up or do a real merge, depending on
531 * whether the merge flag was used.
532 */
533 struct tree *result;
534 struct tree *work;
535 struct merge_options o;
536 if (!opts->merge)
537 return 1;
538
539 /*
540 * Without old->commit, the below is the same as
541 * the two-tree unpack we already tried and failed.
542 */
543 if (!old->commit)
544 return 1;
545
546 /* Do more real merge */
547
548 /*
549 * We update the index fully, then write the
550 * tree from the index, then merge the new
551 * branch with the current tree, with the old
552 * branch as the base. Then we reset the index
553 * (but not the working tree) to the new
554 * branch, leaving the working tree as the
555 * merged version, but skipping unmerged
556 * entries in the index.
557 */
558
559 add_files_to_cache(NULL, NULL, 0);
560 /*
561 * NEEDSWORK: carrying over local changes
562 * when branches have different end-of-line
563 * normalization (or clean+smudge rules) is
564 * a pain; plumb in an option to set
565 * o.renormalize?
566 */
567 init_merge_options(&o);
568 o.verbosity = 0;
569 work = write_tree_from_memory(&o);
570
571 ret = reset_tree(new->commit->tree, opts, 1,
572 writeout_error);
573 if (ret)
574 return ret;
575 o.ancestor = old->name;
576 o.branch1 = new->name;
577 o.branch2 = "local";
578 merge_trees(&o, new->commit->tree, work,
579 old->commit->tree, &result);
580 ret = reset_tree(new->commit->tree, opts, 0,
581 writeout_error);
582 if (ret)
583 return ret;
584 }
585 }
586
587 if (!active_cache_tree)
588 active_cache_tree = cache_tree();
589
590 if (!cache_tree_fully_valid(active_cache_tree))
591 cache_tree_update(&the_index, WRITE_TREE_SILENT | WRITE_TREE_REPAIR);
592
593 if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
594 die(_("unable to write new index file"));
595
596 if (!opts->force && !opts->quiet)
597 show_local_changes(&new->commit->object, &opts->diff_options);
598
599 return 0;
600 }
601
602 static void report_tracking(struct branch_info *new)
603 {
604 struct strbuf sb = STRBUF_INIT;
605 struct branch *branch = branch_get(new->name);
606
607 if (!format_tracking_info(branch, &sb))
608 return;
609 fputs(sb.buf, stdout);
610 strbuf_release(&sb);
611 }
612
613 static void update_refs_for_switch(const struct checkout_opts *opts,
614 struct branch_info *old,
615 struct branch_info *new)
616 {
617 struct strbuf msg = STRBUF_INIT;
618 const char *old_desc, *reflog_msg;
619 if (opts->new_branch) {
620 if (opts->new_orphan_branch) {
621 if (opts->new_branch_log && !log_all_ref_updates) {
622 int temp;
623 struct strbuf log_file = STRBUF_INIT;
624 int ret;
625 const char *ref_name;
626 struct strbuf err = STRBUF_INIT;
627
628 ref_name = mkpath("refs/heads/%s", opts->new_orphan_branch);
629 temp = log_all_ref_updates;
630 log_all_ref_updates = 1;
631 ret = log_ref_setup(ref_name, &log_file, &err);
632 log_all_ref_updates = temp;
633 strbuf_release(&log_file);
634 if (ret) {
635 fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
636 opts->new_orphan_branch, err.buf);
637 strbuf_release(&err);
638 return;
639 }
640 }
641 }
642 else
643 create_branch(old->name, opts->new_branch, new->name,
644 opts->new_branch_force ? 1 : 0,
645 opts->new_branch_log,
646 opts->new_branch_force ? 1 : 0,
647 opts->quiet,
648 opts->track);
649 new->name = opts->new_branch;
650 setup_branch_path(new);
651 }
652
653 old_desc = old->name;
654 if (!old_desc && old->commit)
655 old_desc = sha1_to_hex(old->commit->object.sha1);
656
657 reflog_msg = getenv("GIT_REFLOG_ACTION");
658 if (!reflog_msg)
659 strbuf_addf(&msg, "checkout: moving from %s to %s",
660 old_desc ? old_desc : "(invalid)", new->name);
661 else
662 strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
663
664 if (!strcmp(new->name, "HEAD") && !new->path && !opts->force_detach) {
665 /* Nothing to do. */
666 } else if (opts->force_detach || !new->path) { /* No longer on any branch. */
667 update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
668 REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
669 if (!opts->quiet) {
670 if (old->path && advice_detached_head)
671 detach_advice(new->name);
672 describe_detached_head(_("HEAD is now at"), new->commit);
673 }
674 } else if (new->path) { /* Switch branches. */
675 create_symref("HEAD", new->path, msg.buf);
676 if (!opts->quiet) {
677 if (old->path && !strcmp(new->path, old->path)) {
678 if (opts->new_branch_force)
679 fprintf(stderr, _("Reset branch '%s'\n"),
680 new->name);
681 else
682 fprintf(stderr, _("Already on '%s'\n"),
683 new->name);
684 } else if (opts->new_branch) {
685 if (opts->branch_exists)
686 fprintf(stderr, _("Switched to and reset branch '%s'\n"), new->name);
687 else
688 fprintf(stderr, _("Switched to a new branch '%s'\n"), new->name);
689 } else {
690 fprintf(stderr, _("Switched to branch '%s'\n"),
691 new->name);
692 }
693 }
694 if (old->path && old->name) {
695 if (!ref_exists(old->path) && reflog_exists(old->path))
696 delete_reflog(old->path);
697 }
698 }
699 remove_branch_state();
700 strbuf_release(&msg);
701 if (!opts->quiet &&
702 (new->path || (!opts->force_detach && !strcmp(new->name, "HEAD"))))
703 report_tracking(new);
704 }
705
706 static int add_pending_uninteresting_ref(const char *refname,
707 const struct object_id *oid,
708 int flags, void *cb_data)
709 {
710 add_pending_sha1(cb_data, refname, oid->hash, UNINTERESTING);
711 return 0;
712 }
713
714 static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
715 {
716 strbuf_addstr(sb, " ");
717 strbuf_addstr(sb,
718 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
719 strbuf_addch(sb, ' ');
720 if (!parse_commit(commit))
721 pp_commit_easy(CMIT_FMT_ONELINE, commit, sb);
722 strbuf_addch(sb, '\n');
723 }
724
725 #define ORPHAN_CUTOFF 4
726 static void suggest_reattach(struct commit *commit, struct rev_info *revs)
727 {
728 struct commit *c, *last = NULL;
729 struct strbuf sb = STRBUF_INIT;
730 int lost = 0;
731 while ((c = get_revision(revs)) != NULL) {
732 if (lost < ORPHAN_CUTOFF)
733 describe_one_orphan(&sb, c);
734 last = c;
735 lost++;
736 }
737 if (ORPHAN_CUTOFF < lost) {
738 int more = lost - ORPHAN_CUTOFF;
739 if (more == 1)
740 describe_one_orphan(&sb, last);
741 else
742 strbuf_addf(&sb, _(" ... and %d more.\n"), more);
743 }
744
745 fprintf(stderr,
746 Q_(
747 /* The singular version */
748 "Warning: you are leaving %d commit behind, "
749 "not connected to\n"
750 "any of your branches:\n\n"
751 "%s\n",
752 /* The plural version */
753 "Warning: you are leaving %d commits behind, "
754 "not connected to\n"
755 "any of your branches:\n\n"
756 "%s\n",
757 /* Give ngettext() the count */
758 lost),
759 lost,
760 sb.buf);
761 strbuf_release(&sb);
762
763 if (advice_detached_head)
764 fprintf(stderr,
765 Q_(
766 /* The singular version */
767 "If you want to keep it by creating a new branch, "
768 "this may be a good time\nto do so with:\n\n"
769 " git branch <new-branch-name> %s\n\n",
770 /* The plural version */
771 "If you want to keep them by creating a new branch, "
772 "this may be a good time\nto do so with:\n\n"
773 " git branch <new-branch-name> %s\n\n",
774 /* Give ngettext() the count */
775 lost),
776 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
777 }
778
779 /*
780 * We are about to leave commit that was at the tip of a detached
781 * HEAD. If it is not reachable from any ref, this is the last chance
782 * for the user to do so without resorting to reflog.
783 */
784 static void orphaned_commit_warning(struct commit *old, struct commit *new)
785 {
786 struct rev_info revs;
787 struct object *object = &old->object;
788 struct object_array refs;
789
790 init_revisions(&revs, NULL);
791 setup_revisions(0, NULL, &revs, NULL);
792
793 object->flags &= ~UNINTERESTING;
794 add_pending_object(&revs, object, sha1_to_hex(object->sha1));
795
796 for_each_ref(add_pending_uninteresting_ref, &revs);
797 add_pending_sha1(&revs, "HEAD", new->object.sha1, UNINTERESTING);
798
799 refs = revs.pending;
800 revs.leak_pending = 1;
801
802 if (prepare_revision_walk(&revs))
803 die(_("internal error in revision walk"));
804 if (!(old->object.flags & UNINTERESTING))
805 suggest_reattach(old, &revs);
806 else
807 describe_detached_head(_("Previous HEAD position was"), old);
808
809 clear_commit_marks_for_object_array(&refs, ALL_REV_FLAGS);
810 free(refs.objects);
811 }
812
813 static int switch_branches(const struct checkout_opts *opts,
814 struct branch_info *new)
815 {
816 int ret = 0;
817 struct branch_info old;
818 void *path_to_free;
819 unsigned char rev[20];
820 int flag, writeout_error = 0;
821 memset(&old, 0, sizeof(old));
822 old.path = path_to_free = resolve_refdup("HEAD", 0, rev, &flag);
823 old.commit = lookup_commit_reference_gently(rev, 1);
824 if (!(flag & REF_ISSYMREF))
825 old.path = NULL;
826
827 if (old.path)
828 skip_prefix(old.path, "refs/heads/", &old.name);
829
830 if (!new->name) {
831 new->name = "HEAD";
832 new->commit = old.commit;
833 if (!new->commit)
834 die(_("You are on a branch yet to be born"));
835 parse_commit_or_die(new->commit);
836 }
837
838 ret = merge_working_tree(opts, &old, new, &writeout_error);
839 if (ret) {
840 free(path_to_free);
841 return ret;
842 }
843
844 if (!opts->quiet && !old.path && old.commit &&
845 new->commit != old.commit && !opts->new_worktree_mode)
846 orphaned_commit_warning(old.commit, new->commit);
847
848 update_refs_for_switch(opts, &old, new);
849
850 ret = post_checkout_hook(old.commit, new->commit, 1);
851 free(path_to_free);
852 return ret || writeout_error;
853 }
854
855 static char *junk_work_tree;
856 static char *junk_git_dir;
857 static int is_junk;
858 static pid_t junk_pid;
859
860 static void remove_junk(void)
861 {
862 struct strbuf sb = STRBUF_INIT;
863 if (!is_junk || getpid() != junk_pid)
864 return;
865 if (junk_git_dir) {
866 strbuf_addstr(&sb, junk_git_dir);
867 remove_dir_recursively(&sb, 0);
868 strbuf_reset(&sb);
869 }
870 if (junk_work_tree) {
871 strbuf_addstr(&sb, junk_work_tree);
872 remove_dir_recursively(&sb, 0);
873 }
874 strbuf_release(&sb);
875 }
876
877 static void remove_junk_on_signal(int signo)
878 {
879 remove_junk();
880 sigchain_pop(signo);
881 raise(signo);
882 }
883
884 static int prepare_linked_checkout(const struct checkout_opts *opts,
885 struct branch_info *new)
886 {
887 struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT;
888 struct strbuf sb = STRBUF_INIT;
889 const char *path = opts->new_worktree, *name;
890 struct stat st;
891 struct child_process cp;
892 int counter = 0, len, ret;
893
894 if (!new->commit)
895 die(_("no branch specified"));
896 if (file_exists(path) && !is_empty_dir(path))
897 die(_("'%s' already exists"), path);
898
899 len = strlen(path);
900 while (len && is_dir_sep(path[len - 1]))
901 len--;
902
903 for (name = path + len - 1; name > path; name--)
904 if (is_dir_sep(*name)) {
905 name++;
906 break;
907 }
908 strbuf_addstr(&sb_repo,
909 git_path("worktrees/%.*s", (int)(path + len - name), name));
910 len = sb_repo.len;
911 if (safe_create_leading_directories_const(sb_repo.buf))
912 die_errno(_("could not create leading directories of '%s'"),
913 sb_repo.buf);
914 while (!stat(sb_repo.buf, &st)) {
915 counter++;
916 strbuf_setlen(&sb_repo, len);
917 strbuf_addf(&sb_repo, "%d", counter);
918 }
919 name = strrchr(sb_repo.buf, '/') + 1;
920
921 junk_pid = getpid();
922 atexit(remove_junk);
923 sigchain_push_common(remove_junk_on_signal);
924
925 if (mkdir(sb_repo.buf, 0777))
926 die_errno(_("could not create directory of '%s'"), sb_repo.buf);
927 junk_git_dir = xstrdup(sb_repo.buf);
928 is_junk = 1;
929
930 /*
931 * lock the incomplete repo so prune won't delete it, unlock
932 * after the preparation is over.
933 */
934 strbuf_addf(&sb, "%s/locked", sb_repo.buf);
935 write_file(sb.buf, 1, "initializing\n");
936
937 strbuf_addf(&sb_git, "%s/.git", path);
938 if (safe_create_leading_directories_const(sb_git.buf))
939 die_errno(_("could not create leading directories of '%s'"),
940 sb_git.buf);
941 junk_work_tree = xstrdup(path);
942
943 strbuf_reset(&sb);
944 strbuf_addf(&sb, "%s/gitdir", sb_repo.buf);
945 write_file(sb.buf, 1, "%s\n", real_path(sb_git.buf));
946 write_file(sb_git.buf, 1, "gitdir: %s/worktrees/%s\n",
947 real_path(get_git_common_dir()), name);
948 /*
949 * This is to keep resolve_ref() happy. We need a valid HEAD
950 * or is_git_directory() will reject the directory. Any valid
951 * value would do because this value will be ignored and
952 * replaced at the next (real) checkout.
953 */
954 strbuf_reset(&sb);
955 strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
956 write_file(sb.buf, 1, "%s\n", sha1_to_hex(new->commit->object.sha1));
957 strbuf_reset(&sb);
958 strbuf_addf(&sb, "%s/commondir", sb_repo.buf);
959 write_file(sb.buf, 1, "../..\n");
960
961 if (!opts->quiet)
962 fprintf_ln(stderr, _("Enter %s (identifier %s)"), path, name);
963
964 setenv("GIT_CHECKOUT_NEW_WORKTREE", "1", 1);
965 setenv(GIT_DIR_ENVIRONMENT, sb_git.buf, 1);
966 setenv(GIT_WORK_TREE_ENVIRONMENT, path, 1);
967 memset(&cp, 0, sizeof(cp));
968 cp.git_cmd = 1;
969 cp.argv = opts->saved_argv;
970 ret = run_command(&cp);
971 if (!ret) {
972 is_junk = 0;
973 free(junk_work_tree);
974 free(junk_git_dir);
975 junk_work_tree = NULL;
976 junk_git_dir = NULL;
977 }
978 strbuf_reset(&sb);
979 strbuf_addf(&sb, "%s/locked", sb_repo.buf);
980 unlink_or_warn(sb.buf);
981 strbuf_release(&sb);
982 strbuf_release(&sb_repo);
983 strbuf_release(&sb_git);
984 return ret;
985 }
986
987 static int git_checkout_config(const char *var, const char *value, void *cb)
988 {
989 if (!strcmp(var, "diff.ignoresubmodules")) {
990 struct checkout_opts *opts = cb;
991 handle_ignore_submodules_arg(&opts->diff_options, value);
992 return 0;
993 }
994
995 if (starts_with(var, "submodule."))
996 return parse_submodule_config_option(var, value);
997
998 return git_xmerge_config(var, value, NULL);
999 }
1000
1001 struct tracking_name_data {
1002 /* const */ char *src_ref;
1003 char *dst_ref;
1004 unsigned char *dst_sha1;
1005 int unique;
1006 };
1007
1008 static int check_tracking_name(struct remote *remote, void *cb_data)
1009 {
1010 struct tracking_name_data *cb = cb_data;
1011 struct refspec query;
1012 memset(&query, 0, sizeof(struct refspec));
1013 query.src = cb->src_ref;
1014 if (remote_find_tracking(remote, &query) ||
1015 get_sha1(query.dst, cb->dst_sha1)) {
1016 free(query.dst);
1017 return 0;
1018 }
1019 if (cb->dst_ref) {
1020 free(query.dst);
1021 cb->unique = 0;
1022 return 0;
1023 }
1024 cb->dst_ref = query.dst;
1025 return 0;
1026 }
1027
1028 static const char *unique_tracking_name(const char *name, unsigned char *sha1)
1029 {
1030 struct tracking_name_data cb_data = { NULL, NULL, NULL, 1 };
1031 char src_ref[PATH_MAX];
1032 snprintf(src_ref, PATH_MAX, "refs/heads/%s", name);
1033 cb_data.src_ref = src_ref;
1034 cb_data.dst_sha1 = sha1;
1035 for_each_remote(check_tracking_name, &cb_data);
1036 if (cb_data.unique)
1037 return cb_data.dst_ref;
1038 free(cb_data.dst_ref);
1039 return NULL;
1040 }
1041
1042 static void check_linked_checkout(struct branch_info *new, const char *id)
1043 {
1044 struct strbuf sb = STRBUF_INIT;
1045 struct strbuf path = STRBUF_INIT;
1046 struct strbuf gitdir = STRBUF_INIT;
1047 const char *start, *end;
1048
1049 if (id)
1050 strbuf_addf(&path, "%s/worktrees/%s/HEAD", get_git_common_dir(), id);
1051 else
1052 strbuf_addf(&path, "%s/HEAD", get_git_common_dir());
1053
1054 if (strbuf_read_file(&sb, path.buf, 0) < 0 ||
1055 !skip_prefix(sb.buf, "ref:", &start))
1056 goto done;
1057 while (isspace(*start))
1058 start++;
1059 end = start;
1060 while (*end && !isspace(*end))
1061 end++;
1062 if (strncmp(start, new->path, end - start) || new->path[end - start] != '\0')
1063 goto done;
1064 if (id) {
1065 strbuf_reset(&path);
1066 strbuf_addf(&path, "%s/worktrees/%s/gitdir", get_git_common_dir(), id);
1067 if (strbuf_read_file(&gitdir, path.buf, 0) <= 0)
1068 goto done;
1069 strbuf_rtrim(&gitdir);
1070 } else
1071 strbuf_addstr(&gitdir, get_git_common_dir());
1072 die(_("'%s' is already checked out at '%s'"), new->name, gitdir.buf);
1073 done:
1074 strbuf_release(&path);
1075 strbuf_release(&sb);
1076 strbuf_release(&gitdir);
1077 }
1078
1079 static void check_linked_checkouts(struct branch_info *new)
1080 {
1081 struct strbuf path = STRBUF_INIT;
1082 DIR *dir;
1083 struct dirent *d;
1084
1085 strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
1086 if ((dir = opendir(path.buf)) == NULL) {
1087 strbuf_release(&path);
1088 return;
1089 }
1090
1091 /*
1092 * $GIT_COMMON_DIR/HEAD is practically outside
1093 * $GIT_DIR so resolve_ref_unsafe() won't work (it
1094 * uses git_path). Parse the ref ourselves.
1095 */
1096 check_linked_checkout(new, NULL);
1097
1098 while ((d = readdir(dir)) != NULL) {
1099 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
1100 continue;
1101 check_linked_checkout(new, d->d_name);
1102 }
1103 strbuf_release(&path);
1104 closedir(dir);
1105 }
1106
1107 static int parse_branchname_arg(int argc, const char **argv,
1108 int dwim_new_local_branch_ok,
1109 struct branch_info *new,
1110 struct checkout_opts *opts,
1111 unsigned char rev[20])
1112 {
1113 struct tree **source_tree = &opts->source_tree;
1114 const char **new_branch = &opts->new_branch;
1115 int force_detach = opts->force_detach;
1116 int argcount = 0;
1117 unsigned char branch_rev[20];
1118 const char *arg;
1119 int dash_dash_pos;
1120 int has_dash_dash = 0;
1121 int i;
1122
1123 /*
1124 * case 1: git checkout <ref> -- [<paths>]
1125 *
1126 * <ref> must be a valid tree, everything after the '--' must be
1127 * a path.
1128 *
1129 * case 2: git checkout -- [<paths>]
1130 *
1131 * everything after the '--' must be paths.
1132 *
1133 * case 3: git checkout <something> [--]
1134 *
1135 * (a) If <something> is a commit, that is to
1136 * switch to the branch or detach HEAD at it. As a special case,
1137 * if <something> is A...B (missing A or B means HEAD but you can
1138 * omit at most one side), and if there is a unique merge base
1139 * between A and B, A...B names that merge base.
1140 *
1141 * (b) If <something> is _not_ a commit, either "--" is present
1142 * or <something> is not a path, no -t or -b was given, and
1143 * and there is a tracking branch whose name is <something>
1144 * in one and only one remote, then this is a short-hand to
1145 * fork local <something> from that remote-tracking branch.
1146 *
1147 * (c) Otherwise, if "--" is present, treat it like case (1).
1148 *
1149 * (d) Otherwise :
1150 * - if it's a reference, treat it like case (1)
1151 * - else if it's a path, treat it like case (2)
1152 * - else: fail.
1153 *
1154 * case 4: git checkout <something> <paths>
1155 *
1156 * The first argument must not be ambiguous.
1157 * - If it's *only* a reference, treat it like case (1).
1158 * - If it's only a path, treat it like case (2).
1159 * - else: fail.
1160 *
1161 */
1162 if (!argc)
1163 return 0;
1164
1165 arg = argv[0];
1166 dash_dash_pos = -1;
1167 for (i = 0; i < argc; i++) {
1168 if (!strcmp(argv[i], "--")) {
1169 dash_dash_pos = i;
1170 break;
1171 }
1172 }
1173 if (dash_dash_pos == 0)
1174 return 1; /* case (2) */
1175 else if (dash_dash_pos == 1)
1176 has_dash_dash = 1; /* case (3) or (1) */
1177 else if (dash_dash_pos >= 2)
1178 die(_("only one reference expected, %d given."), dash_dash_pos);
1179
1180 if (!strcmp(arg, "-"))
1181 arg = "@{-1}";
1182
1183 if (get_sha1_mb(arg, rev)) {
1184 /*
1185 * Either case (3) or (4), with <something> not being
1186 * a commit, or an attempt to use case (1) with an
1187 * invalid ref.
1188 *
1189 * It's likely an error, but we need to find out if
1190 * we should auto-create the branch, case (3).(b).
1191 */
1192 int recover_with_dwim = dwim_new_local_branch_ok;
1193
1194 if (check_filename(NULL, arg) && !has_dash_dash)
1195 recover_with_dwim = 0;
1196 /*
1197 * Accept "git checkout foo" and "git checkout foo --"
1198 * as candidates for dwim.
1199 */
1200 if (!(argc == 1 && !has_dash_dash) &&
1201 !(argc == 2 && has_dash_dash))
1202 recover_with_dwim = 0;
1203
1204 if (recover_with_dwim) {
1205 const char *remote = unique_tracking_name(arg, rev);
1206 if (remote) {
1207 *new_branch = arg;
1208 arg = remote;
1209 /* DWIMmed to create local branch, case (3).(b) */
1210 } else {
1211 recover_with_dwim = 0;
1212 }
1213 }
1214
1215 if (!recover_with_dwim) {
1216 if (has_dash_dash)
1217 die(_("invalid reference: %s"), arg);
1218 return argcount;
1219 }
1220 }
1221
1222 /* we can't end up being in (2) anymore, eat the argument */
1223 argcount++;
1224 argv++;
1225 argc--;
1226
1227 new->name = arg;
1228 setup_branch_path(new);
1229
1230 if (!check_refname_format(new->path, 0) &&
1231 !read_ref(new->path, branch_rev))
1232 hashcpy(rev, branch_rev);
1233 else
1234 new->path = NULL; /* not an existing branch */
1235
1236 if (new->path && !force_detach && !*new_branch) {
1237 unsigned char sha1[20];
1238 int flag;
1239 char *head_ref = resolve_refdup("HEAD", 0, sha1, &flag);
1240 if (head_ref &&
1241 (!(flag & REF_ISSYMREF) || strcmp(head_ref, new->path)) &&
1242 !opts->ignore_other_worktrees)
1243 check_linked_checkouts(new);
1244 free(head_ref);
1245 }
1246
1247 new->commit = lookup_commit_reference_gently(rev, 1);
1248 if (!new->commit) {
1249 /* not a commit */
1250 *source_tree = parse_tree_indirect(rev);
1251 } else {
1252 parse_commit_or_die(new->commit);
1253 *source_tree = new->commit->tree;
1254 }
1255
1256 if (!*source_tree) /* case (1): want a tree */
1257 die(_("reference is not a tree: %s"), arg);
1258 if (!has_dash_dash) {/* case (3).(d) -> (1) */
1259 /*
1260 * Do not complain the most common case
1261 * git checkout branch
1262 * even if there happen to be a file called 'branch';
1263 * it would be extremely annoying.
1264 */
1265 if (argc)
1266 verify_non_filename(NULL, arg);
1267 } else {
1268 argcount++;
1269 argv++;
1270 argc--;
1271 }
1272
1273 return argcount;
1274 }
1275
1276 static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
1277 {
1278 int status;
1279 struct strbuf branch_ref = STRBUF_INIT;
1280
1281 if (!opts->new_branch)
1282 die(_("You are on a branch yet to be born"));
1283 strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
1284 status = create_symref("HEAD", branch_ref.buf, "checkout -b");
1285 strbuf_release(&branch_ref);
1286 if (!opts->quiet)
1287 fprintf(stderr, _("Switched to a new branch '%s'\n"),
1288 opts->new_branch);
1289 return status;
1290 }
1291
1292 static int checkout_branch(struct checkout_opts *opts,
1293 struct branch_info *new)
1294 {
1295 if (opts->pathspec.nr)
1296 die(_("paths cannot be used with switching branches"));
1297
1298 if (opts->patch_mode)
1299 die(_("'%s' cannot be used with switching branches"),
1300 "--patch");
1301
1302 if (opts->writeout_stage)
1303 die(_("'%s' cannot be used with switching branches"),
1304 "--ours/--theirs");
1305
1306 if (opts->force && opts->merge)
1307 die(_("'%s' cannot be used with '%s'"), "-f", "-m");
1308
1309 if (opts->force_detach && opts->new_branch)
1310 die(_("'%s' cannot be used with '%s'"),
1311 "--detach", "-b/-B/--orphan");
1312
1313 if (opts->new_orphan_branch) {
1314 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1315 die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
1316 } else if (opts->force_detach) {
1317 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1318 die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
1319 } else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
1320 opts->track = git_branch_track;
1321
1322 if (new->name && !new->commit)
1323 die(_("Cannot switch branch to a non-commit '%s'"),
1324 new->name);
1325
1326 if (opts->new_worktree)
1327 return prepare_linked_checkout(opts, new);
1328
1329 if (!new->commit && opts->new_branch) {
1330 unsigned char rev[20];
1331 int flag;
1332
1333 if (!read_ref_full("HEAD", 0, rev, &flag) &&
1334 (flag & REF_ISSYMREF) && is_null_sha1(rev))
1335 return switch_unborn_to_new_branch(opts);
1336 }
1337 return switch_branches(opts, new);
1338 }
1339
1340 int cmd_checkout(int argc, const char **argv, const char *prefix)
1341 {
1342 struct checkout_opts opts;
1343 struct branch_info new;
1344 char *conflict_style = NULL;
1345 int dwim_new_local_branch = 1;
1346 struct option options[] = {
1347 OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
1348 OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
1349 N_("create and checkout a new branch")),
1350 OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
1351 N_("create/reset and checkout a branch")),
1352 OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
1353 OPT_BOOL(0, "detach", &opts.force_detach, N_("detach the HEAD at named commit")),
1354 OPT_SET_INT('t', "track", &opts.track, N_("set upstream info for new branch"),
1355 BRANCH_TRACK_EXPLICIT),
1356 OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
1357 OPT_SET_INT('2', "ours", &opts.writeout_stage, N_("checkout our version for unmerged files"),
1358 2),
1359 OPT_SET_INT('3', "theirs", &opts.writeout_stage, N_("checkout their version for unmerged files"),
1360 3),
1361 OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)")),
1362 OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
1363 OPT_BOOL(0, "overwrite-ignore", &opts.overwrite_ignore, N_("update ignored files (default)")),
1364 OPT_STRING(0, "conflict", &conflict_style, N_("style"),
1365 N_("conflict style (merge or diff3)")),
1366 OPT_BOOL('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
1367 OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
1368 N_("do not limit pathspecs to sparse entries only")),
1369 OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
1370 N_("second guess 'git checkout <no-such-branch>'")),
1371 OPT_FILENAME(0, "to", &opts.new_worktree,
1372 N_("check a branch out in a separate working directory")),
1373 OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
1374 N_("do not check if another worktree is holding the given ref")),
1375 OPT_END(),
1376 };
1377
1378 memset(&opts, 0, sizeof(opts));
1379 memset(&new, 0, sizeof(new));
1380 opts.overwrite_ignore = 1;
1381 opts.prefix = prefix;
1382
1383 opts.saved_argv = xmalloc(sizeof(const char *) * (argc + 2));
1384 memcpy(opts.saved_argv, argv, sizeof(const char *) * (argc + 1));
1385
1386 gitmodules_config();
1387 git_config(git_checkout_config, &opts);
1388
1389 opts.track = BRANCH_TRACK_UNSPECIFIED;
1390
1391 argc = parse_options(argc, argv, prefix, options, checkout_usage,
1392 PARSE_OPT_KEEP_DASHDASH);
1393
1394 /* recursive execution from checkout_new_worktree() */
1395 opts.new_worktree_mode = getenv("GIT_CHECKOUT_NEW_WORKTREE") != NULL;
1396 if (opts.new_worktree_mode)
1397 opts.new_worktree = NULL;
1398
1399 if (!opts.new_worktree)
1400 setup_work_tree();
1401
1402 if (conflict_style) {
1403 opts.merge = 1; /* implied */
1404 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
1405 }
1406
1407 if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
1408 die(_("-b, -B and --orphan are mutually exclusive"));
1409
1410 /*
1411 * From here on, new_branch will contain the branch to be checked out,
1412 * and new_branch_force and new_orphan_branch will tell us which one of
1413 * -b/-B/--orphan is being used.
1414 */
1415 if (opts.new_branch_force)
1416 opts.new_branch = opts.new_branch_force;
1417
1418 if (opts.new_orphan_branch)
1419 opts.new_branch = opts.new_orphan_branch;
1420
1421 /* --track without -b/-B/--orphan should DWIM */
1422 if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
1423 const char *argv0 = argv[0];
1424 if (!argc || !strcmp(argv0, "--"))
1425 die (_("--track needs a branch name"));
1426 skip_prefix(argv0, "refs/", &argv0);
1427 skip_prefix(argv0, "remotes/", &argv0);
1428 argv0 = strchr(argv0, '/');
1429 if (!argv0 || !argv0[1])
1430 die (_("Missing branch name; try -b"));
1431 opts.new_branch = argv0 + 1;
1432 }
1433
1434 /*
1435 * Extract branch name from command line arguments, so
1436 * all that is left is pathspecs.
1437 *
1438 * Handle
1439 *
1440 * 1) git checkout <tree> -- [<paths>]
1441 * 2) git checkout -- [<paths>]
1442 * 3) git checkout <something> [<paths>]
1443 *
1444 * including "last branch" syntax and DWIM-ery for names of
1445 * remote branches, erroring out for invalid or ambiguous cases.
1446 */
1447 if (argc) {
1448 unsigned char rev[20];
1449 int dwim_ok =
1450 !opts.patch_mode &&
1451 dwim_new_local_branch &&
1452 opts.track == BRANCH_TRACK_UNSPECIFIED &&
1453 !opts.new_branch;
1454 int n = parse_branchname_arg(argc, argv, dwim_ok,
1455 &new, &opts, rev);
1456 argv += n;
1457 argc -= n;
1458 }
1459
1460 if (argc) {
1461 parse_pathspec(&opts.pathspec, 0,
1462 opts.patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
1463 prefix, argv);
1464
1465 if (!opts.pathspec.nr)
1466 die(_("invalid path specification"));
1467
1468 /*
1469 * Try to give more helpful suggestion.
1470 * new_branch && argc > 1 will be caught later.
1471 */
1472 if (opts.new_branch && argc == 1)
1473 die(_("Cannot update paths and switch to branch '%s' at the same time.\n"
1474 "Did you intend to checkout '%s' which can not be resolved as commit?"),
1475 opts.new_branch, argv[0]);
1476
1477 if (opts.force_detach)
1478 die(_("git checkout: --detach does not take a path argument '%s'"),
1479 argv[0]);
1480
1481 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
1482 die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
1483 "checking out of the index."));
1484 }
1485
1486 if (opts.new_branch) {
1487 struct strbuf buf = STRBUF_INIT;
1488
1489 opts.branch_exists =
1490 validate_new_branchname(opts.new_branch, &buf,
1491 !!opts.new_branch_force,
1492 !!opts.new_branch_force);
1493
1494 strbuf_release(&buf);
1495 }
1496
1497 if (opts.patch_mode || opts.pathspec.nr)
1498 return checkout_paths(&opts, new.name);
1499 else
1500 return checkout_branch(&opts, &new);
1501 }