First half of the second batch for 1.8.0
[git/git.git] / builtin / checkout.c
CommitLineData
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1#include "cache.h"
2#include "builtin.h"
3#include "parse-options.h"
4#include "refs.h"
5#include "commit.h"
6#include "tree.h"
7#include "tree-walk.h"
b9d37a54 8#include "cache-tree.h"
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DB
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"
79a1e6b4 16#include "remote.h"
0cf8581e
JH
17#include "blob.h"
18#include "xdiff-interface.h"
19#include "ll-merge.h"
cfc5789a 20#include "resolve-undo.h"
175f6e59 21#include "submodule.h"
7bf0b017 22#include "argv-array.h"
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DB
23
24static const char * const checkout_usage[] = {
25 "git checkout [options] <branch>",
26 "git checkout [options] [<branch>] -- <file>...",
27 NULL,
28};
29
db941099
JH
30struct checkout_opts {
31 int quiet;
32 int merge;
33 int force;
32669671 34 int force_detach;
38901a48 35 int writeout_stage;
db941099 36 int writeout_error;
c1d7036b 37 int overwrite_ignore;
db941099 38
02ac9837
TRC
39 /* not set by parse_options */
40 int branch_exists;
41
db941099 42 const char *new_branch;
02ac9837 43 const char *new_branch_force;
9db5ebf4 44 const char *new_orphan_branch;
db941099
JH
45 int new_branch_log;
46 enum branch_track track;
175f6e59 47 struct diff_options diff_options;
db941099
JH
48};
49
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DB
50static int post_checkout_hook(struct commit *old, struct commit *new,
51 int changed)
52{
ae98a008
SB
53 return run_hook(NULL, "post-checkout",
54 sha1_to_hex(old ? old->object.sha1 : null_sha1),
55 sha1_to_hex(new ? new->object.sha1 : null_sha1),
56 changed ? "1" : "0", NULL);
2292ce47
SB
57 /* "new" can be NULL when checking out from the index before
58 a commit exists. */
ae98a008 59
782c2d65
DB
60}
61
62static int update_some(const unsigned char *sha1, const char *base, int baselen,
671f0707 63 const char *pathname, unsigned mode, int stage, void *context)
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DB
64{
65 int len;
66 struct cache_entry *ce;
67
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DB
68 if (S_ISDIR(mode))
69 return READ_TREE_RECURSIVE;
70
71 len = baselen + strlen(pathname);
72 ce = xcalloc(1, cache_entry_size(len));
73 hashcpy(ce->sha1, sha1);
74 memcpy(ce->name, base, baselen);
75 memcpy(ce->name + baselen, pathname, len - baselen);
b60e188c
TG
76 ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
77 ce->ce_namelen = len;
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DB
78 ce->ce_mode = create_ce_mode(mode);
79 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
80 return 0;
81}
82
83static int read_tree_some(struct tree *tree, const char **pathspec)
84{
f0096c06
NTND
85 struct pathspec ps;
86 init_pathspec(&ps, pathspec);
87 read_tree_recursive(tree, "", 0, 0, &ps, update_some, NULL);
88 free_pathspec(&ps);
782c2d65 89
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DB
90 /* update the index with the given tree's info
91 * for all args, expanding wildcards, and exit
92 * with any non-zero return code.
93 */
94 return 0;
95}
96
8fdcf312
JH
97static int skip_same_name(struct cache_entry *ce, int pos)
98{
99 while (++pos < active_nr &&
100 !strcmp(active_cache[pos]->name, ce->name))
101 ; /* skip */
102 return pos;
103}
104
38901a48
JH
105static int check_stage(int stage, struct cache_entry *ce, int pos)
106{
107 while (pos < active_nr &&
108 !strcmp(active_cache[pos]->name, ce->name)) {
109 if (ce_stage(active_cache[pos]) == stage)
110 return 0;
111 pos++;
112 }
9f97ab08
ÆAB
113 if (stage == 2)
114 return error(_("path '%s' does not have our version"), ce->name);
115 else
116 return error(_("path '%s' does not have their version"), ce->name);
38901a48
JH
117}
118
fbbccd0a 119static int check_stages(unsigned stages, struct cache_entry *ce, int pos)
0cf8581e 120{
fbbccd0a
JH
121 unsigned seen = 0;
122 const char *name = ce->name;
123
124 while (pos < active_nr) {
125 ce = active_cache[pos];
126 if (strcmp(name, ce->name))
127 break;
128 seen |= (1 << ce_stage(ce));
129 pos++;
130 }
131 if ((stages & seen) != stages)
132 return error(_("path '%s' does not have all necessary versions"),
133 name);
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JH
134 return 0;
135}
136
38901a48
JH
137static int checkout_stage(int stage, struct cache_entry *ce, int pos,
138 struct checkout *state)
139{
140 while (pos < active_nr &&
141 !strcmp(active_cache[pos]->name, ce->name)) {
142 if (ce_stage(active_cache[pos]) == stage)
143 return checkout_entry(active_cache[pos], state, NULL);
144 pos++;
145 }
9f97ab08
ÆAB
146 if (stage == 2)
147 return error(_("path '%s' does not have our version"), ce->name);
148 else
149 return error(_("path '%s' does not have their version"), ce->name);
38901a48 150}
8fdcf312 151
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JH
152static int checkout_merged(int pos, struct checkout *state)
153{
154 struct cache_entry *ce = active_cache[pos];
155 const char *path = ce->name;
156 mmfile_t ancestor, ours, theirs;
157 int status;
158 unsigned char sha1[20];
159 mmbuffer_t result_buf;
fbbccd0a 160 unsigned char threeway[3][20];
335c6e40 161 unsigned mode = 0;
0cf8581e 162
fbbccd0a
JH
163 memset(threeway, 0, sizeof(threeway));
164 while (pos < active_nr) {
165 int stage;
166 stage = ce_stage(ce);
167 if (!stage || strcmp(path, ce->name))
168 break;
169 hashcpy(threeway[stage - 1], ce->sha1);
170 if (stage == 2)
171 mode = create_ce_mode(ce->ce_mode);
172 pos++;
173 ce = active_cache[pos];
174 }
175 if (is_null_sha1(threeway[1]) || is_null_sha1(threeway[2]))
176 return error(_("path '%s' does not have necessary versions"), path);
0cf8581e 177
fbbccd0a
JH
178 read_mmblob(&ancestor, threeway[0]);
179 read_mmblob(&ours, threeway[1]);
180 read_mmblob(&theirs, threeway[2]);
0cf8581e 181
18b037a5
JN
182 /*
183 * NEEDSWORK: re-create conflicts from merges with
184 * merge.renormalize set, too
185 */
f0531a29 186 status = ll_merge(&result_buf, path, &ancestor, "base",
712516bc 187 &ours, "ours", &theirs, "theirs", NULL);
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JH
188 free(ancestor.ptr);
189 free(ours.ptr);
190 free(theirs.ptr);
191 if (status < 0 || !result_buf.ptr) {
192 free(result_buf.ptr);
e8a8a4d7 193 return error(_("path '%s': cannot merge"), path);
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JH
194 }
195
196 /*
197 * NEEDSWORK:
198 * There is absolutely no reason to write this as a blob object
3ea3c215 199 * and create a phony cache entry just to leak. This hack is
0cf8581e
JH
200 * primarily to get to the write_entry() machinery that massages
201 * the contents to work-tree format and writes out which only
202 * allows it for a cache entry. The code in write_entry() needs
203 * to be refactored to allow us to feed a <buffer, size, mode>
204 * instead of a cache entry. Such a refactoring would help
205 * merge_recursive as well (it also writes the merge result to the
206 * object database even when it may contain conflicts).
207 */
208 if (write_sha1_file(result_buf.ptr, result_buf.size,
209 blob_type, sha1))
e8a8a4d7 210 die(_("Unable to add merge result for '%s'"), path);
fbbccd0a 211 ce = make_cache_entry(mode, sha1, path, 2, 0);
048f2762 212 if (!ce)
e8a8a4d7 213 die(_("make_cache_entry failed for path '%s'"), path);
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JH
214 status = checkout_entry(ce, state, NULL);
215 return status;
216}
8fdcf312 217
db941099 218static int checkout_paths(struct tree *source_tree, const char **pathspec,
0f64bfa9 219 const char *prefix, struct checkout_opts *opts)
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DB
220{
221 int pos;
222 struct checkout state;
223 static char *ps_matched;
224 unsigned char rev[20];
225 int flag;
226 struct commit *head;
d2b3691b 227 int errs = 0;
38901a48 228 int stage = opts->writeout_stage;
0cf8581e 229 int merge = opts->merge;
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DB
230 int newfd;
231 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
232
233 newfd = hold_locked_index(lock_file, 1);
53996fe5 234 if (read_cache_preload(pathspec) < 0)
e8a8a4d7 235 return error(_("corrupt index file"));
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DB
236
237 if (source_tree)
238 read_tree_some(source_tree, pathspec);
239
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DB
240 for (pos = 0; pathspec[pos]; pos++)
241 ;
242 ps_matched = xcalloc(1, pos);
243
244 for (pos = 0; pos < active_nr; pos++) {
245 struct cache_entry *ce = active_cache[pos];
0a1283bc
JH
246 if (source_tree && !(ce->ce_flags & CE_UPDATE))
247 continue;
0b50922a 248 match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, ps_matched);
782c2d65
DB
249 }
250
0f64bfa9 251 if (report_path_error(ps_matched, pathspec, prefix))
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DB
252 return 1;
253
4421a823
JH
254 /* "checkout -m path" to recreate conflicted state */
255 if (opts->merge)
256 unmerge_cache(pathspec);
257
8fdcf312
JH
258 /* Any unmerged paths? */
259 for (pos = 0; pos < active_nr; pos++) {
260 struct cache_entry *ce = active_cache[pos];
0b50922a 261 if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
8fdcf312
JH
262 if (!ce_stage(ce))
263 continue;
db941099 264 if (opts->force) {
e8a8a4d7 265 warning(_("path '%s' is unmerged"), ce->name);
38901a48
JH
266 } else if (stage) {
267 errs |= check_stage(stage, ce, pos);
0cf8581e 268 } else if (opts->merge) {
fbbccd0a 269 errs |= check_stages((1<<2) | (1<<3), ce, pos);
db941099
JH
270 } else {
271 errs = 1;
e8a8a4d7 272 error(_("path '%s' is unmerged"), ce->name);
db941099 273 }
8fdcf312
JH
274 pos = skip_same_name(ce, pos) - 1;
275 }
276 }
277 if (errs)
278 return 1;
279
d2b3691b 280 /* Now we are committed to check them out */
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DB
281 memset(&state, 0, sizeof(state));
282 state.force = 1;
283 state.refresh_cache = 1;
284 for (pos = 0; pos < active_nr; pos++) {
285 struct cache_entry *ce = active_cache[pos];
0a1283bc
JH
286 if (source_tree && !(ce->ce_flags & CE_UPDATE))
287 continue;
0b50922a 288 if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
8fdcf312
JH
289 if (!ce_stage(ce)) {
290 errs |= checkout_entry(ce, &state, NULL);
291 continue;
292 }
38901a48
JH
293 if (stage)
294 errs |= checkout_stage(stage, ce, pos, &state);
0cf8581e
JH
295 else if (merge)
296 errs |= checkout_merged(pos, &state);
8fdcf312 297 pos = skip_same_name(ce, pos) - 1;
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DB
298 }
299 }
300
75336878
DB
301 if (write_cache(newfd, active_cache, active_nr) ||
302 commit_locked_index(lock_file))
e8a8a4d7 303 die(_("unable to write new index file"));
75336878 304
c6893323 305 read_ref_full("HEAD", rev, 0, &flag);
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DB
306 head = lookup_commit_reference_gently(rev, 1);
307
d2b3691b
JH
308 errs |= post_checkout_hook(head, head, 0);
309 return errs;
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DB
310}
311
175f6e59 312static void show_local_changes(struct object *head, struct diff_options *opts)
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DB
313{
314 struct rev_info rev;
315 /* I think we want full paths, even if we're in a subdirectory. */
316 init_revisions(&rev, NULL);
175f6e59 317 rev.diffopt.flags = opts->flags;
782c2d65 318 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
28452655 319 diff_setup_done(&rev.diffopt);
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DB
320 add_pending_object(&rev, head, NULL);
321 run_diff_index(&rev, 0);
322}
323
b3c0494a 324static void describe_detached_head(const char *msg, struct commit *commit)
782c2d65 325{
f285a2d7 326 struct strbuf sb = STRBUF_INIT;
782c2d65 327 parse_commit(commit);
8b8a5374 328 pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
782c2d65
DB
329 fprintf(stderr, "%s %s... %s\n", msg,
330 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
331 strbuf_release(&sb);
332}
333
6286a08d 334static int reset_tree(struct tree *tree, struct checkout_opts *o, int worktree)
782c2d65
DB
335{
336 struct unpack_trees_options opts;
337 struct tree_desc tree_desc;
bc052d7f 338
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DB
339 memset(&opts, 0, sizeof(opts));
340 opts.head_idx = -1;
6286a08d
JH
341 opts.update = worktree;
342 opts.skip_unmerged = !worktree;
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DB
343 opts.reset = 1;
344 opts.merge = 1;
345 opts.fn = oneway_merge;
e9fc64c6 346 opts.verbose_update = !o->quiet && isatty(2);
34110cd4
LT
347 opts.src_index = &the_index;
348 opts.dst_index = &the_index;
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DB
349 parse_tree(tree);
350 init_tree_desc(&tree_desc, tree->buffer, tree->size);
291d823e
JH
351 switch (unpack_trees(1, &tree_desc, &opts)) {
352 case -2:
353 o->writeout_error = 1;
354 /*
355 * We return 0 nevertheless, as the index is all right
356 * and more importantly we have made best efforts to
357 * update paths in the work tree, and we cannot revert
358 * them.
359 */
360 case 0:
361 return 0;
362 default:
84a5750b 363 return 128;
291d823e 364 }
782c2d65
DB
365}
366
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DB
367struct branch_info {
368 const char *name; /* The short name used */
369 const char *path; /* The full name of a real branch */
370 struct commit *commit; /* The named commit */
371};
372
373static void setup_branch_path(struct branch_info *branch)
374{
f285a2d7 375 struct strbuf buf = STRBUF_INIT;
ae5a6c36 376
a552de75
JH
377 strbuf_branchname(&buf, branch->name);
378 if (strcmp(buf.buf, branch->name))
ae5a6c36 379 branch->name = xstrdup(buf.buf);
a552de75 380 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
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DB
381 branch->path = strbuf_detach(&buf, NULL);
382}
383
384static int merge_working_tree(struct checkout_opts *opts,
75ea38df 385 struct branch_info *old, struct branch_info *new)
782c2d65
DB
386{
387 int ret;
388 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
389 int newfd = hold_locked_index(lock_file, 1);
b96524f8 390
53996fe5 391 if (read_cache_preload(NULL) < 0)
e8a8a4d7 392 return error(_("corrupt index file"));
782c2d65 393
cfc5789a 394 resolve_undo_clear();
782c2d65 395 if (opts->force) {
6286a08d 396 ret = reset_tree(new->commit->tree, opts, 1);
782c2d65
DB
397 if (ret)
398 return ret;
399 } else {
400 struct tree_desc trees[2];
401 struct tree *tree;
402 struct unpack_trees_options topts;
bc052d7f 403
782c2d65
DB
404 memset(&topts, 0, sizeof(topts));
405 topts.head_idx = -1;
34110cd4
LT
406 topts.src_index = &the_index;
407 topts.dst_index = &the_index;
782c2d65 408
e294030f 409 setup_unpack_trees_porcelain(&topts, "checkout");
8ccba008 410
782c2d65
DB
411 refresh_cache(REFRESH_QUIET);
412
413 if (unmerged_cache()) {
e8a8a4d7 414 error(_("you need to resolve your current index first"));
04c9e11f 415 return 1;
782c2d65 416 }
04c9e11f
JH
417
418 /* 2-way merge to the new branch */
fa7b3c2f 419 topts.initial_checkout = is_cache_unborn();
04c9e11f
JH
420 topts.update = 1;
421 topts.merge = 1;
64da3ae5 422 topts.gently = opts->merge && old->commit;
e9fc64c6 423 topts.verbose_update = !opts->quiet && isatty(2);
04c9e11f 424 topts.fn = twoway_merge;
c1d7036b
NTND
425 if (opts->overwrite_ignore) {
426 topts.dir = xcalloc(1, sizeof(*topts.dir));
427 topts.dir->flags |= DIR_SHOW_IGNORED;
428 setup_standard_excludes(topts.dir);
429 }
cc580af8
JK
430 tree = parse_tree_indirect(old->commit ?
431 old->commit->object.sha1 :
dab0d410 432 EMPTY_TREE_SHA1_BIN);
04c9e11f
JH
433 init_tree_desc(&trees[0], tree->buffer, tree->size);
434 tree = parse_tree_indirect(new->commit->object.sha1);
435 init_tree_desc(&trees[1], tree->buffer, tree->size);
436
291d823e 437 ret = unpack_trees(2, trees, &topts);
49d833dc 438 if (ret == -1) {
782c2d65
DB
439 /*
440 * Unpack couldn't do a trivial merge; either
441 * give up or do a real merge, depending on
442 * whether the merge flag was used.
443 */
444 struct tree *result;
445 struct tree *work;
8a2fce18 446 struct merge_options o;
782c2d65
DB
447 if (!opts->merge)
448 return 1;
64da3ae5
JH
449
450 /*
451 * Without old->commit, the below is the same as
452 * the two-tree unpack we already tried and failed.
453 */
454 if (!old->commit)
455 return 1;
782c2d65
DB
456
457 /* Do more real merge */
458
459 /*
460 * We update the index fully, then write the
461 * tree from the index, then merge the new
462 * branch with the current tree, with the old
463 * branch as the base. Then we reset the index
464 * (but not the working tree) to the new
465 * branch, leaving the working tree as the
466 * merged version, but skipping unmerged
467 * entries in the index.
468 */
469
7ae02a30 470 add_files_to_cache(NULL, NULL, 0);
7610fa57
JN
471 /*
472 * NEEDSWORK: carrying over local changes
473 * when branches have different end-of-line
474 * normalization (or clean+smudge rules) is
475 * a pain; plumb in an option to set
476 * o.renormalize?
477 */
8a2fce18
MV
478 init_merge_options(&o);
479 o.verbosity = 0;
480 work = write_tree_from_memory(&o);
782c2d65 481
6286a08d 482 ret = reset_tree(new->commit->tree, opts, 1);
782c2d65
DB
483 if (ret)
484 return ret;
c4151629 485 o.ancestor = old->name;
8a2fce18
MV
486 o.branch1 = new->name;
487 o.branch2 = "local";
488 merge_trees(&o, new->commit->tree, work,
489 old->commit->tree, &result);
6286a08d 490 ret = reset_tree(new->commit->tree, opts, 0);
84a5750b
JH
491 if (ret)
492 return ret;
782c2d65
DB
493 }
494 }
495
496 if (write_cache(newfd, active_cache, active_nr) ||
497 commit_locked_index(lock_file))
e8a8a4d7 498 die(_("unable to write new index file"));
782c2d65 499
7fe4a728 500 if (!opts->force && !opts->quiet)
175f6e59 501 show_local_changes(&new->commit->object, &opts->diff_options);
782c2d65
DB
502
503 return 0;
504}
505
6d21bf96 506static void report_tracking(struct branch_info *new)
79a1e6b4 507{
6d21bf96 508 struct strbuf sb = STRBUF_INIT;
b56fca07 509 struct branch *branch = branch_get(new->name);
79a1e6b4 510
6d21bf96 511 if (!format_tracking_info(branch, &sb))
79a1e6b4 512 return;
6d21bf96
JH
513 fputs(sb.buf, stdout);
514 strbuf_release(&sb);
b0030db3 515}
79a1e6b4 516
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DB
517static void update_refs_for_switch(struct checkout_opts *opts,
518 struct branch_info *old,
519 struct branch_info *new)
520{
f285a2d7 521 struct strbuf msg = STRBUF_INIT;
782c2d65
DB
522 const char *old_desc;
523 if (opts->new_branch) {
3631bf77
EM
524 if (opts->new_orphan_branch) {
525 if (opts->new_branch_log && !log_all_ref_updates) {
526 int temp;
157aaea5 527 char log_file[PATH_MAX];
3631bf77
EM
528 char *ref_name = mkpath("refs/heads/%s", opts->new_orphan_branch);
529
530 temp = log_all_ref_updates;
531 log_all_ref_updates = 1;
157aaea5 532 if (log_ref_setup(ref_name, log_file, sizeof(log_file))) {
e8a8a4d7 533 fprintf(stderr, _("Can not do reflog for '%s'\n"),
3631bf77
EM
534 opts->new_orphan_branch);
535 log_all_ref_updates = temp;
536 return;
537 }
538 log_all_ref_updates = temp;
539 }
540 }
541 else
02ac9837
TRC
542 create_branch(old->name, opts->new_branch, new->name,
543 opts->new_branch_force ? 1 : 0,
39bd6f72
JN
544 opts->new_branch_log,
545 opts->new_branch_force ? 1 : 0,
f9a482e6 546 opts->quiet,
39bd6f72 547 opts->track);
782c2d65
DB
548 new->name = opts->new_branch;
549 setup_branch_path(new);
550 }
551
782c2d65 552 old_desc = old->name;
323e00fd 553 if (!old_desc && old->commit)
782c2d65
DB
554 old_desc = sha1_to_hex(old->commit->object.sha1);
555 strbuf_addf(&msg, "checkout: moving from %s to %s",
323e00fd 556 old_desc ? old_desc : "(invalid)", new->name);
782c2d65 557
f8bd36a4
JN
558 if (!strcmp(new->name, "HEAD") && !new->path && !opts->force_detach) {
559 /* Nothing to do. */
560 } else if (opts->force_detach || !new->path) { /* No longer on any branch. */
561 update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
562 REF_NODEREF, DIE_ON_ERR);
563 if (!opts->quiet) {
564 if (old->path && advice_detached_head)
2857093b 565 detach_advice(new->name);
6c80cd29 566 describe_detached_head(_("HEAD is now at"), new->commit);
f8bd36a4
JN
567 }
568 } else if (new->path) { /* Switch branches. */
782c2d65
DB
569 create_symref("HEAD", new->path, msg.buf);
570 if (!opts->quiet) {
08eaa4be 571 if (old->path && !strcmp(new->path, old->path)) {
39bd6f72
JN
572 if (opts->new_branch_force)
573 fprintf(stderr, _("Reset branch '%s'\n"),
574 new->name);
575 else
576 fprintf(stderr, _("Already on '%s'\n"),
577 new->name);
08eaa4be
ÆAB
578 } else if (opts->new_branch) {
579 if (opts->branch_exists)
580 fprintf(stderr, _("Switched to and reset branch '%s'\n"), new->name);
581 else
582 fprintf(stderr, _("Switched to a new branch '%s'\n"), new->name);
583 } else {
e8a8a4d7 584 fprintf(stderr, _("Switched to branch '%s'\n"),
09a0ec58 585 new->name);
08eaa4be 586 }
782c2d65 587 }
3631bf77
EM
588 if (old->path && old->name) {
589 char log_file[PATH_MAX], ref_file[PATH_MAX];
590
591 git_snpath(log_file, sizeof(log_file), "logs/%s", old->path);
592 git_snpath(ref_file, sizeof(ref_file), "%s", old->path);
593 if (!file_exists(ref_file) && file_exists(log_file))
594 remove_path(log_file);
595 }
782c2d65
DB
596 }
597 remove_branch_state();
598 strbuf_release(&msg);
32669671
JH
599 if (!opts->quiet &&
600 (new->path || (!opts->force_detach && !strcmp(new->name, "HEAD"))))
6d21bf96 601 report_tracking(new);
782c2d65
DB
602}
603
468224e5
RS
604static int add_pending_uninteresting_ref(const char *refname,
605 const unsigned char *sha1,
606 int flags, void *cb_data)
8e2dc6ac 607{
add416a6 608 add_pending_sha1(cb_data, refname, sha1, UNINTERESTING);
5c08dc48
JK
609 return 0;
610}
8e2dc6ac
JH
611
612static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
613{
8e2dc6ac 614 parse_commit(commit);
0be240cc
JK
615 strbuf_addstr(sb, " ");
616 strbuf_addstr(sb,
617 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
618 strbuf_addch(sb, ' ');
f67d2e82 619 pp_commit_easy(CMIT_FMT_ONELINE, commit, sb);
8e2dc6ac
JH
620 strbuf_addch(sb, '\n');
621}
622
623#define ORPHAN_CUTOFF 4
624static void suggest_reattach(struct commit *commit, struct rev_info *revs)
625{
626 struct commit *c, *last = NULL;
627 struct strbuf sb = STRBUF_INIT;
628 int lost = 0;
629 while ((c = get_revision(revs)) != NULL) {
630 if (lost < ORPHAN_CUTOFF)
631 describe_one_orphan(&sb, c);
632 last = c;
633 lost++;
634 }
635 if (ORPHAN_CUTOFF < lost) {
636 int more = lost - ORPHAN_CUTOFF;
637 if (more == 1)
638 describe_one_orphan(&sb, last);
639 else
f06f08b7 640 strbuf_addf(&sb, _(" ... and %d more.\n"), more);
8e2dc6ac
JH
641 }
642
643 fprintf(stderr,
f06f08b7
ÆAB
644 Q_(
645 /* The singular version */
646 "Warning: you are leaving %d commit behind, "
647 "not connected to\n"
648 "any of your branches:\n\n"
0faf2474 649 "%s\n",
f06f08b7
ÆAB
650 /* The plural version */
651 "Warning: you are leaving %d commits behind, "
8e2dc6ac
JH
652 "not connected to\n"
653 "any of your branches:\n\n"
f807b3dc 654 "%s\n",
f06f08b7
ÆAB
655 /* Give ngettext() the count */
656 lost),
657 lost,
f807b3dc 658 sb.buf);
8e2dc6ac 659 strbuf_release(&sb);
f807b3dc
JH
660
661 if (advice_detached_head)
662 fprintf(stderr,
0faf2474 663 _(
f807b3dc
JH
664 "If you want to keep them by creating a new branch, "
665 "this may be a good time\nto do so with:\n\n"
0faf2474 666 " git branch new_branch_name %s\n\n"),
f807b3dc 667 sha1_to_hex(commit->object.sha1));
8e2dc6ac
JH
668}
669
670/*
671 * We are about to leave commit that was at the tip of a detached
672 * HEAD. If it is not reachable from any ref, this is the last chance
673 * for the user to do so without resorting to reflog.
674 */
5d886395 675static void orphaned_commit_warning(struct commit *old, struct commit *new)
8e2dc6ac 676{
8e2dc6ac 677 struct rev_info revs;
5d886395 678 struct object *object = &old->object;
10621419 679 struct object_array refs;
8e2dc6ac
JH
680
681 init_revisions(&revs, NULL);
468224e5
RS
682 setup_revisions(0, NULL, &revs, NULL);
683
684 object->flags &= ~UNINTERESTING;
685 add_pending_object(&revs, object, sha1_to_hex(object->sha1));
686
687 for_each_ref(add_pending_uninteresting_ref, &revs);
5d886395 688 add_pending_sha1(&revs, "HEAD", new->object.sha1, UNINTERESTING);
468224e5 689
10621419
RS
690 refs = revs.pending;
691 revs.leak_pending = 1;
692
8e2dc6ac 693 if (prepare_revision_walk(&revs))
6c80cd29 694 die(_("internal error in revision walk"));
5d886395
JS
695 if (!(old->object.flags & UNINTERESTING))
696 suggest_reattach(old, &revs);
8e2dc6ac 697 else
5d886395 698 describe_detached_head(_("Previous HEAD position was"), old);
5c08dc48 699
86a0a408 700 clear_commit_marks_for_object_array(&refs, ALL_REV_FLAGS);
10621419 701 free(refs.objects);
8e2dc6ac
JH
702}
703
75ea38df 704static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
782c2d65
DB
705{
706 int ret = 0;
707 struct branch_info old;
96ec7b1e 708 void *path_to_free;
782c2d65
DB
709 unsigned char rev[20];
710 int flag;
711 memset(&old, 0, sizeof(old));
96ec7b1e 712 old.path = path_to_free = resolve_refdup("HEAD", rev, 0, &flag);
782c2d65 713 old.commit = lookup_commit_reference_gently(rev, 1);
96ec7b1e 714 if (!(flag & REF_ISSYMREF))
782c2d65
DB
715 old.path = NULL;
716
717 if (old.path && !prefixcmp(old.path, "refs/heads/"))
718 old.name = old.path + strlen("refs/heads/");
719
720 if (!new->name) {
721 new->name = "HEAD";
722 new->commit = old.commit;
723 if (!new->commit)
e8a8a4d7 724 die(_("You are on a branch yet to be born"));
782c2d65
DB
725 parse_commit(new->commit);
726 }
727
75ea38df 728 ret = merge_working_tree(opts, &old, new);
96ec7b1e
NTND
729 if (ret) {
730 free(path_to_free);
782c2d65 731 return ret;
96ec7b1e 732 }
782c2d65 733
77ebd56d 734 if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
5d886395 735 orphaned_commit_warning(old.commit, new->commit);
77ebd56d 736
782c2d65
DB
737 update_refs_for_switch(opts, &old, new);
738
291d823e 739 ret = post_checkout_hook(old.commit, new->commit, 1);
96ec7b1e 740 free(path_to_free);
291d823e 741 return ret || opts->writeout_error;
782c2d65
DB
742}
743
0cf8581e
JH
744static int git_checkout_config(const char *var, const char *value, void *cb)
745{
175f6e59
JS
746 if (!strcmp(var, "diff.ignoresubmodules")) {
747 struct checkout_opts *opts = cb;
748 handle_ignore_submodules_arg(&opts->diff_options, value);
749 return 0;
750 }
23b4c7bc
JL
751
752 if (!prefixcmp(var, "submodule."))
753 return parse_submodule_config_option(var, value);
754
175f6e59 755 return git_xmerge_config(var, value, NULL);
0cf8581e
JH
756}
757
4f353658
TR
758static int interactive_checkout(const char *revision, const char **pathspec,
759 struct checkout_opts *opts)
760{
761 return run_add_interactive(revision, "--patch=checkout", pathspec);
762}
763
70c9ac2f
JH
764struct tracking_name_data {
765 const char *name;
766 char *remote;
767 int unique;
768};
769
770static int check_tracking_name(const char *refname, const unsigned char *sha1,
771 int flags, void *cb_data)
772{
773 struct tracking_name_data *cb = cb_data;
774 const char *slash;
775
776 if (prefixcmp(refname, "refs/remotes/"))
777 return 0;
778 slash = strchr(refname + 13, '/');
779 if (!slash || strcmp(slash + 1, cb->name))
780 return 0;
781 if (cb->remote) {
782 cb->unique = 0;
783 return 0;
784 }
785 cb->remote = xstrdup(refname);
786 return 0;
787}
788
789static const char *unique_tracking_name(const char *name)
790{
66dbfd55
GV
791 struct tracking_name_data cb_data = { NULL, NULL, 1 };
792 cb_data.name = name;
70c9ac2f
JH
793 for_each_ref(check_tracking_name, &cb_data);
794 if (cb_data.unique)
795 return cb_data.remote;
796 free(cb_data.remote);
797 return NULL;
798}
4f353658 799
09ebad6f
JN
800static int parse_branchname_arg(int argc, const char **argv,
801 int dwim_new_local_branch_ok,
802 struct branch_info *new,
803 struct tree **source_tree,
804 unsigned char rev[20],
805 const char **new_branch)
806{
807 int argcount = 0;
808 unsigned char branch_rev[20];
809 const char *arg;
810 int has_dash_dash;
811
812 /*
813 * case 1: git checkout <ref> -- [<paths>]
814 *
815 * <ref> must be a valid tree, everything after the '--' must be
816 * a path.
817 *
818 * case 2: git checkout -- [<paths>]
819 *
820 * everything after the '--' must be paths.
821 *
822 * case 3: git checkout <something> [<paths>]
823 *
824 * With no paths, if <something> is a commit, that is to
825 * switch to the branch or detach HEAD at it. As a special case,
826 * if <something> is A...B (missing A or B means HEAD but you can
827 * omit at most one side), and if there is a unique merge base
828 * between A and B, A...B names that merge base.
829 *
830 * With no paths, if <something> is _not_ a commit, no -t nor -b
831 * was given, and there is a tracking branch whose name is
832 * <something> in one and only one remote, then this is a short-hand
c0791f36 833 * to fork local <something> from that remote-tracking branch.
09ebad6f
JN
834 *
835 * Otherwise <something> shall not be ambiguous.
836 * - If it's *only* a reference, treat it like case (1).
837 * - If it's only a path, treat it like case (2).
838 * - else: fail.
839 *
840 */
841 if (!argc)
842 return 0;
843
844 if (!strcmp(argv[0], "--")) /* case (2) */
845 return 1;
846
847 arg = argv[0];
848 has_dash_dash = (argc > 1) && !strcmp(argv[1], "--");
849
850 if (!strcmp(arg, "-"))
851 arg = "@{-1}";
852
853 if (get_sha1_mb(arg, rev)) {
854 if (has_dash_dash) /* case (1) */
6c80cd29 855 die(_("invalid reference: %s"), arg);
09ebad6f
JN
856 if (dwim_new_local_branch_ok &&
857 !check_filename(NULL, arg) &&
858 argc == 1) {
859 const char *remote = unique_tracking_name(arg);
860 if (!remote || get_sha1(remote, rev))
861 return argcount;
862 *new_branch = arg;
863 arg = remote;
864 /* DWIMmed to create local branch */
865 } else {
866 return argcount;
867 }
868 }
869
870 /* we can't end up being in (2) anymore, eat the argument */
871 argcount++;
872 argv++;
873 argc--;
874
875 new->name = arg;
876 setup_branch_path(new);
877
8d9c5010 878 if (!check_refname_format(new->path, 0) &&
c6893323 879 !read_ref(new->path, branch_rev))
09ebad6f
JN
880 hashcpy(rev, branch_rev);
881 else
882 new->path = NULL; /* not an existing branch */
883
884 new->commit = lookup_commit_reference_gently(rev, 1);
885 if (!new->commit) {
886 /* not a commit */
887 *source_tree = parse_tree_indirect(rev);
888 } else {
889 parse_commit(new->commit);
890 *source_tree = new->commit->tree;
891 }
892
893 if (!*source_tree) /* case (1): want a tree */
6c80cd29 894 die(_("reference is not a tree: %s"), arg);
09ebad6f
JN
895 if (!has_dash_dash) {/* case (3 -> 1) */
896 /*
897 * Do not complain the most common case
898 * git checkout branch
899 * even if there happen to be a file called 'branch';
900 * it would be extremely annoying.
901 */
902 if (argc)
903 verify_non_filename(NULL, arg);
904 } else {
905 argcount++;
906 argv++;
907 argc--;
908 }
909
910 return argcount;
911}
912
abe19980
JH
913static int switch_unborn_to_new_branch(struct checkout_opts *opts)
914{
915 int status;
916 struct strbuf branch_ref = STRBUF_INIT;
917
8ced1aa0
CW
918 if (!opts->new_branch)
919 die(_("You are on a branch yet to be born"));
abe19980
JH
920 strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
921 status = create_symref("HEAD", branch_ref.buf, "checkout -b");
922 strbuf_release(&branch_ref);
923 return status;
924}
925
782c2d65
DB
926int cmd_checkout(int argc, const char **argv, const char *prefix)
927{
928 struct checkout_opts opts;
929 unsigned char rev[20];
782c2d65
DB
930 struct branch_info new;
931 struct tree *source_tree = NULL;
eac5a401 932 char *conflict_style = NULL;
4f353658 933 int patch_mode = 0;
46148dd7 934 int dwim_new_local_branch = 1;
782c2d65 935 struct option options[] = {
8c839683 936 OPT__QUIET(&opts.quiet, "suppress progress reporting"),
4c688751
TRC
937 OPT_STRING('b', NULL, &opts.new_branch, "branch",
938 "create and checkout a new branch"),
02ac9837
TRC
939 OPT_STRING('B', NULL, &opts.new_branch_force, "branch",
940 "create/reset and checkout a branch"),
3695dc0a 941 OPT_BOOLEAN('l', NULL, &opts.new_branch_log, "create reflog for new branch"),
32669671 942 OPT_BOOLEAN(0, "detach", &opts.force_detach, "detach the HEAD at named commit"),
3695dc0a 943 OPT_SET_INT('t', "track", &opts.track, "set upstream info for new branch",
9ed36cfa 944 BRANCH_TRACK_EXPLICIT),
9db5ebf4 945 OPT_STRING(0, "orphan", &opts.new_orphan_branch, "new branch", "new unparented branch"),
3695dc0a 946 OPT_SET_INT('2', "ours", &opts.writeout_stage, "checkout our version for unmerged files",
38901a48 947 2),
3695dc0a 948 OPT_SET_INT('3', "theirs", &opts.writeout_stage, "checkout their version for unmerged files",
38901a48 949 3),
76946b76 950 OPT__FORCE(&opts.force, "force checkout (throw away local modifications)"),
3695dc0a 951 OPT_BOOLEAN('m', "merge", &opts.merge, "perform a 3-way merge with the new branch"),
c1d7036b 952 OPT_BOOLEAN(0, "overwrite-ignore", &opts.overwrite_ignore, "update ignored files (default)"),
eac5a401
JH
953 OPT_STRING(0, "conflict", &conflict_style, "style",
954 "conflict style (merge or diff3)"),
4f353658 955 OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
46148dd7
JH
956 { OPTION_BOOLEAN, 0, "guess", &dwim_new_local_branch, NULL,
957 "second guess 'git checkout no-such-branch'",
958 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
b249b552 959 OPT_END(),
782c2d65
DB
960 };
961
962 memset(&opts, 0, sizeof(opts));
963 memset(&new, 0, sizeof(new));
c1d7036b 964 opts.overwrite_ignore = 1;
782c2d65 965
23b4c7bc 966 gitmodules_config();
175f6e59 967 git_config(git_checkout_config, &opts);
782c2d65 968
9188ed89 969 opts.track = BRANCH_TRACK_UNSPECIFIED;
782c2d65 970
37782920 971 argc = parse_options(argc, argv, prefix, options, checkout_usage,
f5242ebf 972 PARSE_OPT_KEEP_DASHDASH);
859fdaba 973
02ac9837
TRC
974 /* we can assume from now on new_branch = !new_branch_force */
975 if (opts.new_branch && opts.new_branch_force)
e8a8a4d7 976 die(_("-B cannot be used with -b"));
02ac9837
TRC
977
978 /* copy -B over to -b, so that we can just check the latter */
979 if (opts.new_branch_force)
980 opts.new_branch = opts.new_branch_force;
981
4f353658 982 if (patch_mode && (opts.track > 0 || opts.new_branch
32669671
JH
983 || opts.new_branch_log || opts.merge || opts.force
984 || opts.force_detach))
e8a8a4d7 985 die (_("--patch is incompatible with all other options"));
4f353658 986
32669671 987 if (opts.force_detach && (opts.new_branch || opts.new_orphan_branch))
20fc73e3 988 die(_("--detach cannot be used with -b/-B/--orphan"));
32669671 989 if (opts.force_detach && 0 < opts.track)
20fc73e3 990 die(_("--detach cannot be used with -t"));
32669671 991
bb0ceb62 992 /* --track without -b should DWIM */
9188ed89
AR
993 if (0 < opts.track && !opts.new_branch) {
994 const char *argv0 = argv[0];
995 if (!argc || !strcmp(argv0, "--"))
e8a8a4d7 996 die (_("--track needs a branch name"));
9188ed89
AR
997 if (!prefixcmp(argv0, "refs/"))
998 argv0 += 5;
999 if (!prefixcmp(argv0, "remotes/"))
1000 argv0 += 8;
1001 argv0 = strchr(argv0, '/');
1002 if (!argv0 || !argv0[1])
e8a8a4d7 1003 die (_("Missing branch name; try -b"));
9188ed89 1004 opts.new_branch = argv0 + 1;
bb0ceb62
JS
1005 }
1006
9db5ebf4
EM
1007 if (opts.new_orphan_branch) {
1008 if (opts.new_branch)
e8a8a4d7 1009 die(_("--orphan and -b|-B are mutually exclusive"));
3631bf77 1010 if (opts.track > 0)
e8a8a4d7 1011 die(_("--orphan cannot be used with -t"));
9db5ebf4
EM
1012 opts.new_branch = opts.new_orphan_branch;
1013 }
1014
eac5a401
JH
1015 if (conflict_style) {
1016 opts.merge = 1; /* implied */
1017 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
1018 }
1019
859fdaba 1020 if (opts.force && opts.merge)
e8a8a4d7 1021 die(_("git checkout: -f and -m are incompatible"));
859fdaba
PH
1022
1023 /*
09ebad6f
JN
1024 * Extract branch name from command line arguments, so
1025 * all that is left is pathspecs.
859fdaba 1026 *
09ebad6f 1027 * Handle
70c9ac2f 1028 *
09ebad6f
JN
1029 * 1) git checkout <tree> -- [<paths>]
1030 * 2) git checkout -- [<paths>]
1031 * 3) git checkout <something> [<paths>]
859fdaba 1032 *
09ebad6f
JN
1033 * including "last branch" syntax and DWIM-ery for names of
1034 * remote branches, erroring out for invalid or ambiguous cases.
859fdaba 1035 */
782c2d65 1036 if (argc) {
09ebad6f
JN
1037 int dwim_ok =
1038 !patch_mode &&
1039 dwim_new_local_branch &&
1040 opts.track == BRANCH_TRACK_UNSPECIFIED &&
1041 !opts.new_branch;
f8bd36a4 1042 int n = parse_branchname_arg(argc, argv, dwim_ok,
09ebad6f
JN
1043 &new, &source_tree, rev, &opts.new_branch);
1044 argv += n;
1045 argc -= n;
782c2d65
DB
1046 }
1047
70c9ac2f
JH
1048 if (opts.track == BRANCH_TRACK_UNSPECIFIED)
1049 opts.track = git_branch_track;
1050
782c2d65
DB
1051 if (argc) {
1052 const char **pathspec = get_pathspec(prefix, argv);
301e42ed
AR
1053
1054 if (!pathspec)
e8a8a4d7 1055 die(_("invalid path specification"));
301e42ed 1056
4f353658
TR
1057 if (patch_mode)
1058 return interactive_checkout(new.name, pathspec, &opts);
1059
782c2d65 1060 /* Checkout paths */
0cf8581e 1061 if (opts.new_branch) {
782c2d65 1062 if (argc == 1) {
e8a8a4d7 1063 die(_("git checkout: updating paths is incompatible with switching branches.\nDid you intend to checkout '%s' which can not be resolved as commit?"), argv[0]);
782c2d65 1064 } else {
e8a8a4d7 1065 die(_("git checkout: updating paths is incompatible with switching branches."));
782c2d65
DB
1066 }
1067 }
1068
32669671 1069 if (opts.force_detach)
20fc73e3 1070 die(_("git checkout: --detach does not take a path argument"));
32669671 1071
0cf8581e 1072 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
e8a8a4d7 1073 die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\nchecking out of the index."));
0cf8581e 1074
0f64bfa9 1075 return checkout_paths(source_tree, pathspec, prefix, &opts);
782c2d65
DB
1076 }
1077
4f353658
TR
1078 if (patch_mode)
1079 return interactive_checkout(new.name, NULL, &opts);
1080
352eadc4 1081 if (opts.new_branch) {
f285a2d7 1082 struct strbuf buf = STRBUF_INIT;
55c4a673 1083
fa799376 1084 opts.branch_exists = validate_new_branchname(opts.new_branch, &buf,
39bd6f72
JN
1085 !!opts.new_branch_force,
1086 !!opts.new_branch_force);
55c4a673 1087
352eadc4
DB
1088 strbuf_release(&buf);
1089 }
1090
782c2d65 1091 if (new.name && !new.commit) {
e8a8a4d7 1092 die(_("Cannot switch branch to a non-commit."));
782c2d65 1093 }
38901a48 1094 if (opts.writeout_stage)
e8a8a4d7 1095 die(_("--ours/--theirs is incompatible with switching branches."));
782c2d65 1096
8338f771 1097 if (!new.commit && opts.new_branch) {
abe19980
JH
1098 unsigned char rev[20];
1099 int flag;
1100
aa47ec99
JH
1101 if (!read_ref_full("HEAD", rev, 0, &flag) &&
1102 (flag & REF_ISSYMREF) && is_null_sha1(rev))
abe19980
JH
1103 return switch_unborn_to_new_branch(&opts);
1104 }
75ea38df 1105 return switch_branches(&opts, &new);
782c2d65 1106}