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