checkout: factor out functions to new lib file
[git.git] / builtin / checkout.c
blobad8f94044cfcfe4b73176c35093a5f2994ca77c0
1 #include "builtin.h"
2 #include "config.h"
3 #include "checkout.h"
4 #include "lockfile.h"
5 #include "parse-options.h"
6 #include "refs.h"
7 #include "commit.h"
8 #include "tree.h"
9 #include "tree-walk.h"
10 #include "cache-tree.h"
11 #include "unpack-trees.h"
12 #include "dir.h"
13 #include "run-command.h"
14 #include "merge-recursive.h"
15 #include "branch.h"
16 #include "diff.h"
17 #include "revision.h"
18 #include "remote.h"
19 #include "blob.h"
20 #include "xdiff-interface.h"
21 #include "ll-merge.h"
22 #include "resolve-undo.h"
23 #include "submodule-config.h"
24 #include "submodule.h"
26 static const char * const checkout_usage[] = {
27 N_("git checkout [<options>] <branch>"),
28 N_("git checkout [<options>] [<branch>] -- <file>..."),
29 NULL,
32 struct checkout_opts {
33 int patch_mode;
34 int quiet;
35 int merge;
36 int force;
37 int force_detach;
38 int writeout_stage;
39 int overwrite_ignore;
40 int ignore_skipworktree;
41 int ignore_other_worktrees;
42 int show_progress;
44 const char *new_branch;
45 const char *new_branch_force;
46 const char *new_orphan_branch;
47 int new_branch_log;
48 enum branch_track track;
49 struct diff_options diff_options;
51 int branch_exists;
52 const char *prefix;
53 struct pathspec pathspec;
54 struct tree *source_tree;
57 static int post_checkout_hook(struct commit *old, struct commit *new,
58 int changed)
60 return run_hook_le(NULL, "post-checkout",
61 oid_to_hex(old ? &old->object.oid : &null_oid),
62 oid_to_hex(new ? &new->object.oid : &null_oid),
63 changed ? "1" : "0", NULL);
64 /* "new" can be NULL when checking out from the index before
65 a commit exists. */
69 static int update_some(const unsigned char *sha1, struct strbuf *base,
70 const char *pathname, unsigned mode, int stage, void *context)
72 int len;
73 struct cache_entry *ce;
74 int pos;
76 if (S_ISDIR(mode))
77 return READ_TREE_RECURSIVE;
79 len = base->len + strlen(pathname);
80 ce = xcalloc(1, cache_entry_size(len));
81 hashcpy(ce->oid.hash, sha1);
82 memcpy(ce->name, base->buf, base->len);
83 memcpy(ce->name + base->len, pathname, len - base->len);
84 ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
85 ce->ce_namelen = len;
86 ce->ce_mode = create_ce_mode(mode);
89 * If the entry is the same as the current index, we can leave the old
90 * entry in place. Whether it is UPTODATE or not, checkout_entry will
91 * do the right thing.
93 pos = cache_name_pos(ce->name, ce->ce_namelen);
94 if (pos >= 0) {
95 struct cache_entry *old = active_cache[pos];
96 if (ce->ce_mode == old->ce_mode &&
97 !oidcmp(&ce->oid, &old->oid)) {
98 old->ce_flags |= CE_UPDATE;
99 free(ce);
100 return 0;
104 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
105 return 0;
108 static int read_tree_some(struct tree *tree, const struct pathspec *pathspec)
110 read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
112 /* update the index with the given tree's info
113 * for all args, expanding wildcards, and exit
114 * with any non-zero return code.
116 return 0;
119 static int skip_same_name(const struct cache_entry *ce, int pos)
121 while (++pos < active_nr &&
122 !strcmp(active_cache[pos]->name, ce->name))
123 ; /* skip */
124 return pos;
127 static int check_stage(int stage, const struct cache_entry *ce, int pos)
129 while (pos < active_nr &&
130 !strcmp(active_cache[pos]->name, ce->name)) {
131 if (ce_stage(active_cache[pos]) == stage)
132 return 0;
133 pos++;
135 if (stage == 2)
136 return error(_("path '%s' does not have our version"), ce->name);
137 else
138 return error(_("path '%s' does not have their version"), ce->name);
141 static int check_stages(unsigned stages, const struct cache_entry *ce, int pos)
143 unsigned seen = 0;
144 const char *name = ce->name;
146 while (pos < active_nr) {
147 ce = active_cache[pos];
148 if (strcmp(name, ce->name))
149 break;
150 seen |= (1 << ce_stage(ce));
151 pos++;
153 if ((stages & seen) != stages)
154 return error(_("path '%s' does not have all necessary versions"),
155 name);
156 return 0;
159 static int checkout_stage(int stage, const struct cache_entry *ce, int pos,
160 const struct checkout *state)
162 while (pos < active_nr &&
163 !strcmp(active_cache[pos]->name, ce->name)) {
164 if (ce_stage(active_cache[pos]) == stage)
165 return checkout_entry(active_cache[pos], state, NULL);
166 pos++;
168 if (stage == 2)
169 return error(_("path '%s' does not have our version"), ce->name);
170 else
171 return error(_("path '%s' does not have their version"), ce->name);
174 static int checkout_merged(int pos, const struct checkout *state)
176 struct cache_entry *ce = active_cache[pos];
177 const char *path = ce->name;
178 mmfile_t ancestor, ours, theirs;
179 int status;
180 struct object_id oid;
181 mmbuffer_t result_buf;
182 struct object_id threeway[3];
183 unsigned mode = 0;
185 memset(threeway, 0, sizeof(threeway));
186 while (pos < active_nr) {
187 int stage;
188 stage = ce_stage(ce);
189 if (!stage || strcmp(path, ce->name))
190 break;
191 oidcpy(&threeway[stage - 1], &ce->oid);
192 if (stage == 2)
193 mode = create_ce_mode(ce->ce_mode);
194 pos++;
195 ce = active_cache[pos];
197 if (is_null_oid(&threeway[1]) || is_null_oid(&threeway[2]))
198 return error(_("path '%s' does not have necessary versions"), path);
200 read_mmblob(&ancestor, &threeway[0]);
201 read_mmblob(&ours, &threeway[1]);
202 read_mmblob(&theirs, &threeway[2]);
205 * NEEDSWORK: re-create conflicts from merges with
206 * merge.renormalize set, too
208 status = ll_merge(&result_buf, path, &ancestor, "base",
209 &ours, "ours", &theirs, "theirs", NULL);
210 free(ancestor.ptr);
211 free(ours.ptr);
212 free(theirs.ptr);
213 if (status < 0 || !result_buf.ptr) {
214 free(result_buf.ptr);
215 return error(_("path '%s': cannot merge"), path);
219 * NEEDSWORK:
220 * There is absolutely no reason to write this as a blob object
221 * and create a phony cache entry. This hack is primarily to get
222 * to the write_entry() machinery that massages the contents to
223 * work-tree format and writes out which only allows it for a
224 * cache entry. The code in write_entry() needs to be refactored
225 * to allow us to feed a <buffer, size, mode> instead of a cache
226 * entry. Such a refactoring would help merge_recursive as well
227 * (it also writes the merge result to the object database even
228 * when it may contain conflicts).
230 if (write_sha1_file(result_buf.ptr, result_buf.size,
231 blob_type, oid.hash))
232 die(_("Unable to add merge result for '%s'"), path);
233 free(result_buf.ptr);
234 ce = make_cache_entry(mode, oid.hash, path, 2, 0);
235 if (!ce)
236 die(_("make_cache_entry failed for path '%s'"), path);
237 status = checkout_entry(ce, state, NULL);
238 free(ce);
239 return status;
242 static int checkout_paths(const struct checkout_opts *opts,
243 const char *revision)
245 int pos;
246 struct checkout state = CHECKOUT_INIT;
247 static char *ps_matched;
248 struct object_id rev;
249 struct commit *head;
250 int errs = 0;
251 struct lock_file lock_file = LOCK_INIT;
253 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
254 die(_("'%s' cannot be used with updating paths"), "--track");
256 if (opts->new_branch_log)
257 die(_("'%s' cannot be used with updating paths"), "-l");
259 if (opts->force && opts->patch_mode)
260 die(_("'%s' cannot be used with updating paths"), "-f");
262 if (opts->force_detach)
263 die(_("'%s' cannot be used with updating paths"), "--detach");
265 if (opts->merge && opts->patch_mode)
266 die(_("'%s' cannot be used with %s"), "--merge", "--patch");
268 if (opts->force && opts->merge)
269 die(_("'%s' cannot be used with %s"), "-f", "-m");
271 if (opts->new_branch)
272 die(_("Cannot update paths and switch to branch '%s' at the same time."),
273 opts->new_branch);
275 if (opts->patch_mode)
276 return run_add_interactive(revision, "--patch=checkout",
277 &opts->pathspec);
279 hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
280 if (read_cache_preload(&opts->pathspec) < 0)
281 return error(_("index file corrupt"));
283 if (opts->source_tree)
284 read_tree_some(opts->source_tree, &opts->pathspec);
286 ps_matched = xcalloc(opts->pathspec.nr, 1);
289 * Make sure all pathspecs participated in locating the paths
290 * to be checked out.
292 for (pos = 0; pos < active_nr; pos++) {
293 struct cache_entry *ce = active_cache[pos];
294 ce->ce_flags &= ~CE_MATCHED;
295 if (!opts->ignore_skipworktree && ce_skip_worktree(ce))
296 continue;
297 if (opts->source_tree && !(ce->ce_flags & CE_UPDATE))
299 * "git checkout tree-ish -- path", but this entry
300 * is in the original index; it will not be checked
301 * out to the working tree and it does not matter
302 * if pathspec matched this entry. We will not do
303 * anything to this entry at all.
305 continue;
307 * Either this entry came from the tree-ish we are
308 * checking the paths out of, or we are checking out
309 * of the index.
311 * If it comes from the tree-ish, we already know it
312 * matches the pathspec and could just stamp
313 * CE_MATCHED to it from update_some(). But we still
314 * need ps_matched and read_tree_recursive (and
315 * eventually tree_entry_interesting) cannot fill
316 * ps_matched yet. Once it can, we can avoid calling
317 * match_pathspec() for _all_ entries when
318 * opts->source_tree != NULL.
320 if (ce_path_match(ce, &opts->pathspec, ps_matched))
321 ce->ce_flags |= CE_MATCHED;
324 if (report_path_error(ps_matched, &opts->pathspec, opts->prefix)) {
325 free(ps_matched);
326 return 1;
328 free(ps_matched);
330 /* "checkout -m path" to recreate conflicted state */
331 if (opts->merge)
332 unmerge_marked_index(&the_index);
334 /* Any unmerged paths? */
335 for (pos = 0; pos < active_nr; pos++) {
336 const struct cache_entry *ce = active_cache[pos];
337 if (ce->ce_flags & CE_MATCHED) {
338 if (!ce_stage(ce))
339 continue;
340 if (opts->force) {
341 warning(_("path '%s' is unmerged"), ce->name);
342 } else if (opts->writeout_stage) {
343 errs |= check_stage(opts->writeout_stage, ce, pos);
344 } else if (opts->merge) {
345 errs |= check_stages((1<<2) | (1<<3), ce, pos);
346 } else {
347 errs = 1;
348 error(_("path '%s' is unmerged"), ce->name);
350 pos = skip_same_name(ce, pos) - 1;
353 if (errs)
354 return 1;
356 /* Now we are committed to check them out */
357 state.force = 1;
358 state.refresh_cache = 1;
359 state.istate = &the_index;
361 enable_delayed_checkout(&state);
362 for (pos = 0; pos < active_nr; pos++) {
363 struct cache_entry *ce = active_cache[pos];
364 if (ce->ce_flags & CE_MATCHED) {
365 if (!ce_stage(ce)) {
366 errs |= checkout_entry(ce, &state, NULL);
367 continue;
369 if (opts->writeout_stage)
370 errs |= checkout_stage(opts->writeout_stage, ce, pos, &state);
371 else if (opts->merge)
372 errs |= checkout_merged(pos, &state);
373 pos = skip_same_name(ce, pos) - 1;
376 errs |= finish_delayed_checkout(&state);
378 if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
379 die(_("unable to write new index file"));
381 read_ref_full("HEAD", 0, &rev, NULL);
382 head = lookup_commit_reference_gently(&rev, 1);
384 errs |= post_checkout_hook(head, head, 0);
385 return errs;
388 static void show_local_changes(struct object *head,
389 const struct diff_options *opts)
391 struct rev_info rev;
392 /* I think we want full paths, even if we're in a subdirectory. */
393 init_revisions(&rev, NULL);
394 rev.diffopt.flags = opts->flags;
395 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
396 diff_setup_done(&rev.diffopt);
397 add_pending_object(&rev, head, NULL);
398 run_diff_index(&rev, 0);
401 static void describe_detached_head(const char *msg, struct commit *commit)
403 struct strbuf sb = STRBUF_INIT;
404 if (!parse_commit(commit))
405 pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
406 fprintf(stderr, "%s %s... %s\n", msg,
407 find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV), sb.buf);
408 strbuf_release(&sb);
411 static int reset_tree(struct tree *tree, const struct checkout_opts *o,
412 int worktree, int *writeout_error)
414 struct unpack_trees_options opts;
415 struct tree_desc tree_desc;
417 memset(&opts, 0, sizeof(opts));
418 opts.head_idx = -1;
419 opts.update = worktree;
420 opts.skip_unmerged = !worktree;
421 opts.reset = 1;
422 opts.merge = 1;
423 opts.fn = oneway_merge;
424 opts.verbose_update = o->show_progress;
425 opts.src_index = &the_index;
426 opts.dst_index = &the_index;
427 parse_tree(tree);
428 init_tree_desc(&tree_desc, tree->buffer, tree->size);
429 switch (unpack_trees(1, &tree_desc, &opts)) {
430 case -2:
431 *writeout_error = 1;
433 * We return 0 nevertheless, as the index is all right
434 * and more importantly we have made best efforts to
435 * update paths in the work tree, and we cannot revert
436 * them.
438 /* fallthrough */
439 case 0:
440 return 0;
441 default:
442 return 128;
446 struct branch_info {
447 const char *name; /* The short name used */
448 const char *path; /* The full name of a real branch */
449 struct commit *commit; /* The named commit */
451 * if not null the branch is detached because it's already
452 * checked out in this checkout
454 char *checkout;
457 static void setup_branch_path(struct branch_info *branch)
459 struct strbuf buf = STRBUF_INIT;
461 strbuf_branchname(&buf, branch->name, INTERPRET_BRANCH_LOCAL);
462 if (strcmp(buf.buf, branch->name))
463 branch->name = xstrdup(buf.buf);
464 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
465 branch->path = strbuf_detach(&buf, NULL);
468 static int merge_working_tree(const struct checkout_opts *opts,
469 struct branch_info *old,
470 struct branch_info *new,
471 int *writeout_error)
473 int ret;
474 struct lock_file lock_file = LOCK_INIT;
476 hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
477 if (read_cache_preload(NULL) < 0)
478 return error(_("index file corrupt"));
480 resolve_undo_clear();
481 if (opts->force) {
482 ret = reset_tree(new->commit->tree, opts, 1, writeout_error);
483 if (ret)
484 return ret;
485 } else {
486 struct tree_desc trees[2];
487 struct tree *tree;
488 struct unpack_trees_options topts;
490 memset(&topts, 0, sizeof(topts));
491 topts.head_idx = -1;
492 topts.src_index = &the_index;
493 topts.dst_index = &the_index;
495 setup_unpack_trees_porcelain(&topts, "checkout");
497 refresh_cache(REFRESH_QUIET);
499 if (unmerged_cache()) {
500 error(_("you need to resolve your current index first"));
501 return 1;
504 /* 2-way merge to the new branch */
505 topts.initial_checkout = is_cache_unborn();
506 topts.update = 1;
507 topts.merge = 1;
508 topts.gently = opts->merge && old->commit;
509 topts.verbose_update = opts->show_progress;
510 topts.fn = twoway_merge;
511 if (opts->overwrite_ignore) {
512 topts.dir = xcalloc(1, sizeof(*topts.dir));
513 topts.dir->flags |= DIR_SHOW_IGNORED;
514 setup_standard_excludes(topts.dir);
516 tree = parse_tree_indirect(old->commit ?
517 &old->commit->object.oid :
518 &empty_tree_oid);
519 init_tree_desc(&trees[0], tree->buffer, tree->size);
520 tree = parse_tree_indirect(&new->commit->object.oid);
521 init_tree_desc(&trees[1], tree->buffer, tree->size);
523 ret = unpack_trees(2, trees, &topts);
524 if (ret == -1) {
526 * Unpack couldn't do a trivial merge; either
527 * give up or do a real merge, depending on
528 * whether the merge flag was used.
530 struct tree *result;
531 struct tree *work;
532 struct merge_options o;
533 if (!opts->merge)
534 return 1;
537 * Without old->commit, the below is the same as
538 * the two-tree unpack we already tried and failed.
540 if (!old->commit)
541 return 1;
543 /* Do more real merge */
546 * We update the index fully, then write the
547 * tree from the index, then merge the new
548 * branch with the current tree, with the old
549 * branch as the base. Then we reset the index
550 * (but not the working tree) to the new
551 * branch, leaving the working tree as the
552 * merged version, but skipping unmerged
553 * entries in the index.
556 add_files_to_cache(NULL, NULL, 0);
558 * NEEDSWORK: carrying over local changes
559 * when branches have different end-of-line
560 * normalization (or clean+smudge rules) is
561 * a pain; plumb in an option to set
562 * o.renormalize?
564 init_merge_options(&o);
565 o.verbosity = 0;
566 work = write_tree_from_memory(&o);
568 ret = reset_tree(new->commit->tree, opts, 1,
569 writeout_error);
570 if (ret)
571 return ret;
572 o.ancestor = old->name;
573 o.branch1 = new->name;
574 o.branch2 = "local";
575 ret = merge_trees(&o, new->commit->tree, work,
576 old->commit->tree, &result);
577 if (ret < 0)
578 exit(128);
579 ret = reset_tree(new->commit->tree, opts, 0,
580 writeout_error);
581 strbuf_release(&o.obuf);
582 if (ret)
583 return ret;
587 if (!active_cache_tree)
588 active_cache_tree = cache_tree();
590 if (!cache_tree_fully_valid(active_cache_tree))
591 cache_tree_update(&the_index, WRITE_TREE_SILENT | WRITE_TREE_REPAIR);
593 if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
594 die(_("unable to write new index file"));
596 if (!opts->force && !opts->quiet)
597 show_local_changes(&new->commit->object, &opts->diff_options);
599 return 0;
602 static void report_tracking(struct branch_info *new)
604 struct strbuf sb = STRBUF_INIT;
605 struct branch *branch = branch_get(new->name);
607 if (!format_tracking_info(branch, &sb))
608 return;
609 fputs(sb.buf, stdout);
610 strbuf_release(&sb);
613 static void update_refs_for_switch(const struct checkout_opts *opts,
614 struct branch_info *old,
615 struct branch_info *new)
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 char *refname;
623 refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
624 if (opts->new_branch_log &&
625 !should_autocreate_reflog(refname)) {
626 int ret;
627 struct strbuf err = STRBUF_INIT;
629 ret = safe_create_reflog(refname, 1, &err);
630 if (ret) {
631 fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
632 opts->new_orphan_branch, err.buf);
633 strbuf_release(&err);
634 free(refname);
635 return;
637 strbuf_release(&err);
639 free(refname);
641 else
642 create_branch(opts->new_branch, new->name,
643 opts->new_branch_force ? 1 : 0,
644 opts->new_branch_log,
645 opts->new_branch_force ? 1 : 0,
646 opts->quiet,
647 opts->track);
648 new->name = opts->new_branch;
649 setup_branch_path(new);
652 old_desc = old->name;
653 if (!old_desc && old->commit)
654 old_desc = oid_to_hex(&old->commit->object.oid);
656 reflog_msg = getenv("GIT_REFLOG_ACTION");
657 if (!reflog_msg)
658 strbuf_addf(&msg, "checkout: moving from %s to %s",
659 old_desc ? old_desc : "(invalid)", new->name);
660 else
661 strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
663 if (!strcmp(new->name, "HEAD") && !new->path && !opts->force_detach) {
664 /* Nothing to do. */
665 } else if (opts->force_detach || !new->path) { /* No longer on any branch. */
666 update_ref(msg.buf, "HEAD", &new->commit->object.oid, NULL,
667 REF_NO_DEREF, UPDATE_REFS_DIE_ON_ERR);
668 if (!opts->quiet) {
669 if (old->path &&
670 advice_detached_head && !opts->force_detach)
671 detach_advice(new->name);
672 describe_detached_head(_("HEAD is now at"), new->commit);
674 } else if (new->path) { /* Switch branches. */
675 if (create_symref("HEAD", new->path, msg.buf) < 0)
676 die(_("unable to update HEAD"));
677 if (!opts->quiet) {
678 if (old->path && !strcmp(new->path, old->path)) {
679 if (opts->new_branch_force)
680 fprintf(stderr, _("Reset branch '%s'\n"),
681 new->name);
682 else
683 fprintf(stderr, _("Already on '%s'\n"),
684 new->name);
685 } else if (opts->new_branch) {
686 if (opts->branch_exists)
687 fprintf(stderr, _("Switched to and reset branch '%s'\n"), new->name);
688 else
689 fprintf(stderr, _("Switched to a new branch '%s'\n"), new->name);
690 } else {
691 fprintf(stderr, _("Switched to branch '%s'\n"),
692 new->name);
695 if (old->path && old->name) {
696 if (!ref_exists(old->path) && reflog_exists(old->path))
697 delete_reflog(old->path);
700 remove_branch_state();
701 strbuf_release(&msg);
702 if (!opts->quiet &&
703 (new->path || (!opts->force_detach && !strcmp(new->name, "HEAD"))))
704 report_tracking(new);
707 static int add_pending_uninteresting_ref(const char *refname,
708 const struct object_id *oid,
709 int flags, void *cb_data)
711 add_pending_oid(cb_data, refname, oid, UNINTERESTING);
712 return 0;
715 static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
717 strbuf_addstr(sb, " ");
718 strbuf_add_unique_abbrev(sb, commit->object.oid.hash, 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');
725 #define ORPHAN_CUTOFF 4
726 static void suggest_reattach(struct commit *commit, struct rev_info *revs)
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++;
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);
745 fprintf(stderr,
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);
763 if (advice_detached_head)
764 fprintf(stderr,
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.oid.hash, DEFAULT_ABBREV));
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.
784 static void orphaned_commit_warning(struct commit *old, struct commit *new)
786 struct rev_info revs;
787 struct object *object = &old->object;
788 struct object_array refs;
790 init_revisions(&revs, NULL);
791 setup_revisions(0, NULL, &revs, NULL);
793 object->flags &= ~UNINTERESTING;
794 add_pending_object(&revs, object, oid_to_hex(&object->oid));
796 for_each_ref(add_pending_uninteresting_ref, &revs);
797 add_pending_oid(&revs, "HEAD", &new->object.oid, UNINTERESTING);
799 /* Save pending objects, so they can be cleaned up later. */
800 refs = revs.pending;
801 revs.leak_pending = 1;
804 * prepare_revision_walk (together with .leak_pending = 1) makes us
805 * the sole owner of the list of pending objects.
807 if (prepare_revision_walk(&revs))
808 die(_("internal error in revision walk"));
809 if (!(old->object.flags & UNINTERESTING))
810 suggest_reattach(old, &revs);
811 else
812 describe_detached_head(_("Previous HEAD position was"), old);
814 /* Clean up objects used, as they will be reused. */
815 clear_commit_marks_for_object_array(&refs, ALL_REV_FLAGS);
817 object_array_clear(&refs);
820 static int switch_branches(const struct checkout_opts *opts,
821 struct branch_info *new)
823 int ret = 0;
824 struct branch_info old;
825 void *path_to_free;
826 struct object_id rev;
827 int flag, writeout_error = 0;
828 memset(&old, 0, sizeof(old));
829 old.path = path_to_free = resolve_refdup("HEAD", 0, &rev, &flag);
830 if (old.path)
831 old.commit = lookup_commit_reference_gently(&rev, 1);
832 if (!(flag & REF_ISSYMREF))
833 old.path = NULL;
835 if (old.path)
836 skip_prefix(old.path, "refs/heads/", &old.name);
838 if (!new->name) {
839 new->name = "HEAD";
840 new->commit = old.commit;
841 if (!new->commit)
842 die(_("You are on a branch yet to be born"));
843 parse_commit_or_die(new->commit);
846 ret = merge_working_tree(opts, &old, new, &writeout_error);
847 if (ret) {
848 free(path_to_free);
849 return ret;
852 if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
853 orphaned_commit_warning(old.commit, new->commit);
855 update_refs_for_switch(opts, &old, new);
857 ret = post_checkout_hook(old.commit, new->commit, 1);
858 free(path_to_free);
859 return ret || writeout_error;
862 static int git_checkout_config(const char *var, const char *value, void *cb)
864 if (!strcmp(var, "diff.ignoresubmodules")) {
865 struct checkout_opts *opts = cb;
866 handle_ignore_submodules_arg(&opts->diff_options, value);
867 return 0;
870 if (starts_with(var, "submodule."))
871 return git_default_submodule_config(var, value, NULL);
873 return git_xmerge_config(var, value, NULL);
876 static int parse_branchname_arg(int argc, const char **argv,
877 int dwim_new_local_branch_ok,
878 struct branch_info *new,
879 struct checkout_opts *opts,
880 struct object_id *rev)
882 struct tree **source_tree = &opts->source_tree;
883 const char **new_branch = &opts->new_branch;
884 int argcount = 0;
885 struct object_id branch_rev;
886 const char *arg;
887 int dash_dash_pos;
888 int has_dash_dash = 0;
889 int i;
892 * case 1: git checkout <ref> -- [<paths>]
894 * <ref> must be a valid tree, everything after the '--' must be
895 * a path.
897 * case 2: git checkout -- [<paths>]
899 * everything after the '--' must be paths.
901 * case 3: git checkout <something> [--]
903 * (a) If <something> is a commit, that is to
904 * switch to the branch or detach HEAD at it. As a special case,
905 * if <something> is A...B (missing A or B means HEAD but you can
906 * omit at most one side), and if there is a unique merge base
907 * between A and B, A...B names that merge base.
909 * (b) If <something> is _not_ a commit, either "--" is present
910 * or <something> is not a path, no -t or -b was given, and
911 * and there is a tracking branch whose name is <something>
912 * in one and only one remote, then this is a short-hand to
913 * fork local <something> from that remote-tracking branch.
915 * (c) Otherwise, if "--" is present, treat it like case (1).
917 * (d) Otherwise :
918 * - if it's a reference, treat it like case (1)
919 * - else if it's a path, treat it like case (2)
920 * - else: fail.
922 * case 4: git checkout <something> <paths>
924 * The first argument must not be ambiguous.
925 * - If it's *only* a reference, treat it like case (1).
926 * - If it's only a path, treat it like case (2).
927 * - else: fail.
930 if (!argc)
931 return 0;
933 arg = argv[0];
934 dash_dash_pos = -1;
935 for (i = 0; i < argc; i++) {
936 if (!strcmp(argv[i], "--")) {
937 dash_dash_pos = i;
938 break;
941 if (dash_dash_pos == 0)
942 return 1; /* case (2) */
943 else if (dash_dash_pos == 1)
944 has_dash_dash = 1; /* case (3) or (1) */
945 else if (dash_dash_pos >= 2)
946 die(_("only one reference expected, %d given."), dash_dash_pos);
948 if (!strcmp(arg, "-"))
949 arg = "@{-1}";
951 if (get_oid_mb(arg, rev)) {
953 * Either case (3) or (4), with <something> not being
954 * a commit, or an attempt to use case (1) with an
955 * invalid ref.
957 * It's likely an error, but we need to find out if
958 * we should auto-create the branch, case (3).(b).
960 int recover_with_dwim = dwim_new_local_branch_ok;
962 if (!has_dash_dash &&
963 (check_filename(opts->prefix, arg) || !no_wildcard(arg)))
964 recover_with_dwim = 0;
966 * Accept "git checkout foo" and "git checkout foo --"
967 * as candidates for dwim.
969 if (!(argc == 1 && !has_dash_dash) &&
970 !(argc == 2 && has_dash_dash))
971 recover_with_dwim = 0;
973 if (recover_with_dwim) {
974 const char *remote = unique_tracking_name(arg, rev);
975 if (remote) {
976 *new_branch = arg;
977 arg = remote;
978 /* DWIMmed to create local branch, case (3).(b) */
979 } else {
980 recover_with_dwim = 0;
984 if (!recover_with_dwim) {
985 if (has_dash_dash)
986 die(_("invalid reference: %s"), arg);
987 return argcount;
991 /* we can't end up being in (2) anymore, eat the argument */
992 argcount++;
993 argv++;
994 argc--;
996 new->name = arg;
997 setup_branch_path(new);
999 if (!check_refname_format(new->path, 0) &&
1000 !read_ref(new->path, &branch_rev))
1001 oidcpy(rev, &branch_rev);
1002 else
1003 new->path = NULL; /* not an existing branch */
1005 new->commit = lookup_commit_reference_gently(rev, 1);
1006 if (!new->commit) {
1007 /* not a commit */
1008 *source_tree = parse_tree_indirect(rev);
1009 } else {
1010 parse_commit_or_die(new->commit);
1011 *source_tree = new->commit->tree;
1014 if (!*source_tree) /* case (1): want a tree */
1015 die(_("reference is not a tree: %s"), arg);
1016 if (!has_dash_dash) { /* case (3).(d) -> (1) */
1018 * Do not complain the most common case
1019 * git checkout branch
1020 * even if there happen to be a file called 'branch';
1021 * it would be extremely annoying.
1023 if (argc)
1024 verify_non_filename(opts->prefix, arg);
1025 } else {
1026 argcount++;
1027 argv++;
1028 argc--;
1031 return argcount;
1034 static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
1036 int status;
1037 struct strbuf branch_ref = STRBUF_INIT;
1039 if (!opts->new_branch)
1040 die(_("You are on a branch yet to be born"));
1041 strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
1042 status = create_symref("HEAD", branch_ref.buf, "checkout -b");
1043 strbuf_release(&branch_ref);
1044 if (!opts->quiet)
1045 fprintf(stderr, _("Switched to a new branch '%s'\n"),
1046 opts->new_branch);
1047 return status;
1050 static int checkout_branch(struct checkout_opts *opts,
1051 struct branch_info *new)
1053 if (opts->pathspec.nr)
1054 die(_("paths cannot be used with switching branches"));
1056 if (opts->patch_mode)
1057 die(_("'%s' cannot be used with switching branches"),
1058 "--patch");
1060 if (opts->writeout_stage)
1061 die(_("'%s' cannot be used with switching branches"),
1062 "--ours/--theirs");
1064 if (opts->force && opts->merge)
1065 die(_("'%s' cannot be used with '%s'"), "-f", "-m");
1067 if (opts->force_detach && opts->new_branch)
1068 die(_("'%s' cannot be used with '%s'"),
1069 "--detach", "-b/-B/--orphan");
1071 if (opts->new_orphan_branch) {
1072 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1073 die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
1074 } else if (opts->force_detach) {
1075 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1076 die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
1077 } else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
1078 opts->track = git_branch_track;
1080 if (new->name && !new->commit)
1081 die(_("Cannot switch branch to a non-commit '%s'"),
1082 new->name);
1084 if (new->path && !opts->force_detach && !opts->new_branch &&
1085 !opts->ignore_other_worktrees) {
1086 int flag;
1087 char *head_ref = resolve_refdup("HEAD", 0, NULL, &flag);
1088 if (head_ref &&
1089 (!(flag & REF_ISSYMREF) || strcmp(head_ref, new->path)))
1090 die_if_checked_out(new->path, 1);
1091 free(head_ref);
1094 if (!new->commit && opts->new_branch) {
1095 struct object_id rev;
1096 int flag;
1098 if (!read_ref_full("HEAD", 0, &rev, &flag) &&
1099 (flag & REF_ISSYMREF) && is_null_oid(&rev))
1100 return switch_unborn_to_new_branch(opts);
1102 return switch_branches(opts, new);
1105 int cmd_checkout(int argc, const char **argv, const char *prefix)
1107 struct checkout_opts opts;
1108 struct branch_info new;
1109 char *conflict_style = NULL;
1110 int dwim_new_local_branch = 1;
1111 struct option options[] = {
1112 OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
1113 OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
1114 N_("create and checkout a new branch")),
1115 OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
1116 N_("create/reset and checkout a branch")),
1117 OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
1118 OPT_BOOL(0, "detach", &opts.force_detach, N_("detach HEAD at named commit")),
1119 OPT_SET_INT('t', "track", &opts.track, N_("set upstream info for new branch"),
1120 BRANCH_TRACK_EXPLICIT),
1121 OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
1122 OPT_SET_INT('2', "ours", &opts.writeout_stage, N_("checkout our version for unmerged files"),
1124 OPT_SET_INT('3', "theirs", &opts.writeout_stage, N_("checkout their version for unmerged files"),
1126 OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)")),
1127 OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
1128 OPT_BOOL(0, "overwrite-ignore", &opts.overwrite_ignore, N_("update ignored files (default)")),
1129 OPT_STRING(0, "conflict", &conflict_style, N_("style"),
1130 N_("conflict style (merge or diff3)")),
1131 OPT_BOOL('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
1132 OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
1133 N_("do not limit pathspecs to sparse entries only")),
1134 OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
1135 N_("second guess 'git checkout <no-such-branch>'")),
1136 OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
1137 N_("do not check if another worktree is holding the given ref")),
1138 { OPTION_CALLBACK, 0, "recurse-submodules", NULL,
1139 "checkout", "control recursive updating of submodules",
1140 PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
1141 OPT_BOOL(0, "progress", &opts.show_progress, N_("force progress reporting")),
1142 OPT_END(),
1145 memset(&opts, 0, sizeof(opts));
1146 memset(&new, 0, sizeof(new));
1147 opts.overwrite_ignore = 1;
1148 opts.prefix = prefix;
1149 opts.show_progress = -1;
1151 git_config(git_checkout_config, &opts);
1153 opts.track = BRANCH_TRACK_UNSPECIFIED;
1155 argc = parse_options(argc, argv, prefix, options, checkout_usage,
1156 PARSE_OPT_KEEP_DASHDASH);
1158 if (opts.show_progress < 0) {
1159 if (opts.quiet)
1160 opts.show_progress = 0;
1161 else
1162 opts.show_progress = isatty(2);
1165 if (conflict_style) {
1166 opts.merge = 1; /* implied */
1167 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
1170 if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
1171 die(_("-b, -B and --orphan are mutually exclusive"));
1174 * From here on, new_branch will contain the branch to be checked out,
1175 * and new_branch_force and new_orphan_branch will tell us which one of
1176 * -b/-B/--orphan is being used.
1178 if (opts.new_branch_force)
1179 opts.new_branch = opts.new_branch_force;
1181 if (opts.new_orphan_branch)
1182 opts.new_branch = opts.new_orphan_branch;
1184 /* --track without -b/-B/--orphan should DWIM */
1185 if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
1186 const char *argv0 = argv[0];
1187 if (!argc || !strcmp(argv0, "--"))
1188 die (_("--track needs a branch name"));
1189 skip_prefix(argv0, "refs/", &argv0);
1190 skip_prefix(argv0, "remotes/", &argv0);
1191 argv0 = strchr(argv0, '/');
1192 if (!argv0 || !argv0[1])
1193 die (_("Missing branch name; try -b"));
1194 opts.new_branch = argv0 + 1;
1198 * Extract branch name from command line arguments, so
1199 * all that is left is pathspecs.
1201 * Handle
1203 * 1) git checkout <tree> -- [<paths>]
1204 * 2) git checkout -- [<paths>]
1205 * 3) git checkout <something> [<paths>]
1207 * including "last branch" syntax and DWIM-ery for names of
1208 * remote branches, erroring out for invalid or ambiguous cases.
1210 if (argc) {
1211 struct object_id rev;
1212 int dwim_ok =
1213 !opts.patch_mode &&
1214 dwim_new_local_branch &&
1215 opts.track == BRANCH_TRACK_UNSPECIFIED &&
1216 !opts.new_branch;
1217 int n = parse_branchname_arg(argc, argv, dwim_ok,
1218 &new, &opts, &rev);
1219 argv += n;
1220 argc -= n;
1223 if (argc) {
1224 parse_pathspec(&opts.pathspec, 0,
1225 opts.patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
1226 prefix, argv);
1228 if (!opts.pathspec.nr)
1229 die(_("invalid path specification"));
1232 * Try to give more helpful suggestion.
1233 * new_branch && argc > 1 will be caught later.
1235 if (opts.new_branch && argc == 1)
1236 die(_("'%s' is not a commit and a branch '%s' cannot be created from it"),
1237 argv[0], opts.new_branch);
1239 if (opts.force_detach)
1240 die(_("git checkout: --detach does not take a path argument '%s'"),
1241 argv[0]);
1243 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
1244 die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
1245 "checking out of the index."));
1248 if (opts.new_branch) {
1249 struct strbuf buf = STRBUF_INIT;
1251 opts.branch_exists =
1252 validate_new_branchname(opts.new_branch, &buf,
1253 !!opts.new_branch_force,
1254 !!opts.new_branch_force);
1256 strbuf_release(&buf);
1259 UNLEAK(opts);
1260 if (opts.patch_mode || opts.pathspec.nr)
1261 return checkout_paths(&opts, new.name);
1262 else
1263 return checkout_branch(&opts, &new);