Documentation/SubmittingPatches: discuss first then submit
[git] / builtin-branch.c
1 /*
2  * Builtin "git branch"
3  *
4  * Copyright (c) 2006 Kristian Høgsberg <krh@redhat.com>
5  * Based on git-branch.sh by Junio C Hamano.
6  */
7
8 #include "cache.h"
9 #include "color.h"
10 #include "refs.h"
11 #include "commit.h"
12 #include "builtin.h"
13 #include "remote.h"
14 #include "parse-options.h"
15
16 static const char * const builtin_branch_usage[] = {
17         "git-branch [options] [-r | -a]",
18         "git-branch [options] [-l] [-f] <branchname> [<start-point>]",
19         "git-branch [options] [-r] (-d | -D) <branchname>",
20         "git-branch [options] (-m | -M) [<oldbranch>] <newbranch>",
21         NULL
22 };
23
24 #define REF_UNKNOWN_TYPE    0x00
25 #define REF_LOCAL_BRANCH    0x01
26 #define REF_REMOTE_BRANCH   0x02
27 #define REF_TAG             0x04
28
29 static const char *head;
30 static unsigned char head_sha1[20];
31
32 static int branch_track = 1;
33
34 static int branch_use_color;
35 static char branch_colors[][COLOR_MAXLEN] = {
36         "\033[m",       /* reset */
37         "",             /* PLAIN (normal) */
38         "\033[31m",     /* REMOTE (red) */
39         "",             /* LOCAL (normal) */
40         "\033[32m",     /* CURRENT (green) */
41 };
42 enum color_branch {
43         COLOR_BRANCH_RESET = 0,
44         COLOR_BRANCH_PLAIN = 1,
45         COLOR_BRANCH_REMOTE = 2,
46         COLOR_BRANCH_LOCAL = 3,
47         COLOR_BRANCH_CURRENT = 4,
48 };
49
50 static int parse_branch_color_slot(const char *var, int ofs)
51 {
52         if (!strcasecmp(var+ofs, "plain"))
53                 return COLOR_BRANCH_PLAIN;
54         if (!strcasecmp(var+ofs, "reset"))
55                 return COLOR_BRANCH_RESET;
56         if (!strcasecmp(var+ofs, "remote"))
57                 return COLOR_BRANCH_REMOTE;
58         if (!strcasecmp(var+ofs, "local"))
59                 return COLOR_BRANCH_LOCAL;
60         if (!strcasecmp(var+ofs, "current"))
61                 return COLOR_BRANCH_CURRENT;
62         die("bad config variable '%s'", var);
63 }
64
65 static int git_branch_config(const char *var, const char *value)
66 {
67         if (!strcmp(var, "color.branch")) {
68                 branch_use_color = git_config_colorbool(var, value, -1);
69                 return 0;
70         }
71         if (!prefixcmp(var, "color.branch.")) {
72                 int slot = parse_branch_color_slot(var, 13);
73                 color_parse(value, var, branch_colors[slot]);
74                 return 0;
75         }
76         if (!strcmp(var, "branch.autosetupmerge"))
77                         branch_track = git_config_bool(var, value);
78
79         return git_default_config(var, value);
80 }
81
82 static const char *branch_get_color(enum color_branch ix)
83 {
84         if (branch_use_color)
85                 return branch_colors[ix];
86         return "";
87 }
88
89 static int delete_branches(int argc, const char **argv, int force, int kinds)
90 {
91         struct commit *rev, *head_rev = head_rev;
92         unsigned char sha1[20];
93         char *name = NULL;
94         const char *fmt, *remote;
95         char section[PATH_MAX];
96         int i;
97         int ret = 0;
98
99         switch (kinds) {
100         case REF_REMOTE_BRANCH:
101                 fmt = "refs/remotes/%s";
102                 remote = "remote ";
103                 force = 1;
104                 break;
105         case REF_LOCAL_BRANCH:
106                 fmt = "refs/heads/%s";
107                 remote = "";
108                 break;
109         default:
110                 die("cannot use -a with -d");
111         }
112
113         if (!force) {
114                 head_rev = lookup_commit_reference(head_sha1);
115                 if (!head_rev)
116                         die("Couldn't look up commit object for HEAD");
117         }
118         for (i = 0; i < argc; i++) {
119                 if (kinds == REF_LOCAL_BRANCH && !strcmp(head, argv[i])) {
120                         error("Cannot delete the branch '%s' "
121                                 "which you are currently on.", argv[i]);
122                         ret = 1;
123                         continue;
124                 }
125
126                 if (name)
127                         free(name);
128
129                 name = xstrdup(mkpath(fmt, argv[i]));
130                 if (!resolve_ref(name, sha1, 1, NULL)) {
131                         error("%sbranch '%s' not found.",
132                                         remote, argv[i]);
133                         ret = 1;
134                         continue;
135                 }
136
137                 rev = lookup_commit_reference(sha1);
138                 if (!rev) {
139                         error("Couldn't look up commit object for '%s'", name);
140                         ret = 1;
141                         continue;
142                 }
143
144                 /* This checks whether the merge bases of branch and
145                  * HEAD contains branch -- which means that the HEAD
146                  * contains everything in both.
147                  */
148
149                 if (!force &&
150                     !in_merge_bases(rev, &head_rev, 1)) {
151                         error("The branch '%s' is not an ancestor of "
152                                 "your current HEAD.\n"
153                                 "If you are sure you want to delete it, "
154                                 "run 'git branch -D %s'.", argv[i], argv[i]);
155                         ret = 1;
156                         continue;
157                 }
158
159                 if (delete_ref(name, sha1)) {
160                         error("Error deleting %sbranch '%s'", remote,
161                                argv[i]);
162                         ret = 1;
163                 } else {
164                         printf("Deleted %sbranch %s.\n", remote, argv[i]);
165                         snprintf(section, sizeof(section), "branch.%s",
166                                  argv[i]);
167                         if (git_config_rename_section(section, NULL) < 0)
168                                 warning("Update of config-file failed");
169                 }
170         }
171
172         if (name)
173                 free(name);
174
175         return(ret);
176 }
177
178 struct ref_item {
179         char *name;
180         unsigned int kind;
181         unsigned char sha1[20];
182 };
183
184 struct ref_list {
185         int index, alloc, maxwidth;
186         struct ref_item *list;
187         struct commit_list *with_commit;
188         int kinds;
189 };
190
191 static int has_commit(const unsigned char *sha1, struct commit_list *with_commit)
192 {
193         struct commit *commit;
194
195         if (!with_commit)
196                 return 1;
197         commit = lookup_commit_reference_gently(sha1, 1);
198         if (!commit)
199                 return 0;
200         while (with_commit) {
201                 struct commit *other;
202
203                 other = with_commit->item;
204                 with_commit = with_commit->next;
205                 if (in_merge_bases(other, &commit, 1))
206                         return 1;
207         }
208         return 0;
209 }
210
211 static int append_ref(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
212 {
213         struct ref_list *ref_list = (struct ref_list*)(cb_data);
214         struct ref_item *newitem;
215         int kind = REF_UNKNOWN_TYPE;
216         int len;
217
218         /* Detect kind */
219         if (!prefixcmp(refname, "refs/heads/")) {
220                 kind = REF_LOCAL_BRANCH;
221                 refname += 11;
222         } else if (!prefixcmp(refname, "refs/remotes/")) {
223                 kind = REF_REMOTE_BRANCH;
224                 refname += 13;
225         } else if (!prefixcmp(refname, "refs/tags/")) {
226                 kind = REF_TAG;
227                 refname += 10;
228         }
229
230         /* Filter with with_commit if specified */
231         if (!has_commit(sha1, ref_list->with_commit))
232                 return 0;
233
234         /* Don't add types the caller doesn't want */
235         if ((kind & ref_list->kinds) == 0)
236                 return 0;
237
238         /* Resize buffer */
239         if (ref_list->index >= ref_list->alloc) {
240                 ref_list->alloc = alloc_nr(ref_list->alloc);
241                 ref_list->list = xrealloc(ref_list->list,
242                                 ref_list->alloc * sizeof(struct ref_item));
243         }
244
245         /* Record the new item */
246         newitem = &(ref_list->list[ref_list->index++]);
247         newitem->name = xstrdup(refname);
248         newitem->kind = kind;
249         hashcpy(newitem->sha1, sha1);
250         len = strlen(newitem->name);
251         if (len > ref_list->maxwidth)
252                 ref_list->maxwidth = len;
253
254         return 0;
255 }
256
257 static void free_ref_list(struct ref_list *ref_list)
258 {
259         int i;
260
261         for (i = 0; i < ref_list->index; i++)
262                 free(ref_list->list[i].name);
263         free(ref_list->list);
264 }
265
266 static int ref_cmp(const void *r1, const void *r2)
267 {
268         struct ref_item *c1 = (struct ref_item *)(r1);
269         struct ref_item *c2 = (struct ref_item *)(r2);
270
271         if (c1->kind != c2->kind)
272                 return c1->kind - c2->kind;
273         return strcmp(c1->name, c2->name);
274 }
275
276 static void print_ref_item(struct ref_item *item, int maxwidth, int verbose,
277                            int abbrev, int current)
278 {
279         char c;
280         int color;
281         struct commit *commit;
282
283         switch (item->kind) {
284         case REF_LOCAL_BRANCH:
285                 color = COLOR_BRANCH_LOCAL;
286                 break;
287         case REF_REMOTE_BRANCH:
288                 color = COLOR_BRANCH_REMOTE;
289                 break;
290         default:
291                 color = COLOR_BRANCH_PLAIN;
292                 break;
293         }
294
295         c = ' ';
296         if (current) {
297                 c = '*';
298                 color = COLOR_BRANCH_CURRENT;
299         }
300
301         if (verbose) {
302                 struct strbuf subject;
303                 const char *sub = " **** invalid ref ****";
304
305                 strbuf_init(&subject, 0);
306
307                 commit = lookup_commit(item->sha1);
308                 if (commit && !parse_commit(commit)) {
309                         pretty_print_commit(CMIT_FMT_ONELINE, commit,
310                                             &subject, 0, NULL, NULL, 0, 0);
311                         sub = subject.buf;
312                 }
313                 printf("%c %s%-*s%s %s %s\n", c, branch_get_color(color),
314                        maxwidth, item->name,
315                        branch_get_color(COLOR_BRANCH_RESET),
316                        find_unique_abbrev(item->sha1, abbrev), sub);
317                 strbuf_release(&subject);
318         } else {
319                 printf("%c %s%s%s\n", c, branch_get_color(color), item->name,
320                        branch_get_color(COLOR_BRANCH_RESET));
321         }
322 }
323
324 static void print_ref_list(int kinds, int detached, int verbose, int abbrev, struct commit_list *with_commit)
325 {
326         int i;
327         struct ref_list ref_list;
328
329         memset(&ref_list, 0, sizeof(ref_list));
330         ref_list.kinds = kinds;
331         ref_list.with_commit = with_commit;
332         for_each_ref(append_ref, &ref_list);
333
334         qsort(ref_list.list, ref_list.index, sizeof(struct ref_item), ref_cmp);
335
336         detached = (detached && (kinds & REF_LOCAL_BRANCH));
337         if (detached && has_commit(head_sha1, with_commit)) {
338                 struct ref_item item;
339                 item.name = xstrdup("(no branch)");
340                 item.kind = REF_LOCAL_BRANCH;
341                 hashcpy(item.sha1, head_sha1);
342                 if (strlen(item.name) > ref_list.maxwidth)
343                               ref_list.maxwidth = strlen(item.name);
344                 print_ref_item(&item, ref_list.maxwidth, verbose, abbrev, 1);
345                 free(item.name);
346         }
347
348         for (i = 0; i < ref_list.index; i++) {
349                 int current = !detached &&
350                         (ref_list.list[i].kind == REF_LOCAL_BRANCH) &&
351                         !strcmp(ref_list.list[i].name, head);
352                 print_ref_item(&ref_list.list[i], ref_list.maxwidth, verbose,
353                                abbrev, current);
354         }
355
356         free_ref_list(&ref_list);
357 }
358
359 struct tracking {
360         struct refspec spec;
361         char *src;
362         const char *remote;
363         int matches;
364 };
365
366 static int find_tracked_branch(struct remote *remote, void *priv)
367 {
368         struct tracking *tracking = priv;
369
370         if (!remote_find_tracking(remote, &tracking->spec)) {
371                 if (++tracking->matches == 1) {
372                         tracking->src = tracking->spec.src;
373                         tracking->remote = remote->name;
374                 } else {
375                         free(tracking->spec.src);
376                         if (tracking->src) {
377                                 free(tracking->src);
378                                 tracking->src = NULL;
379                         }
380                 }
381                 tracking->spec.src = NULL;
382         }
383
384         return 0;
385 }
386
387
388 /*
389  * This is called when new_ref is branched off of orig_ref, and tries
390  * to infer the settings for branch.<new_ref>.{remote,merge} from the
391  * config.
392  */
393 static int setup_tracking(const char *new_ref, const char *orig_ref)
394 {
395         char key[1024];
396         struct tracking tracking;
397
398         if (strlen(new_ref) > 1024 - 7 - 7 - 1)
399                 return error("Tracking not set up: name too long: %s",
400                                 new_ref);
401
402         memset(&tracking, 0, sizeof(tracking));
403         tracking.spec.dst = (char *)orig_ref;
404         if (for_each_remote(find_tracked_branch, &tracking) ||
405                         !tracking.matches)
406                 return 1;
407
408         if (tracking.matches > 1)
409                 return error("Not tracking: ambiguous information for ref %s",
410                                 orig_ref);
411
412         if (tracking.matches == 1) {
413                 sprintf(key, "branch.%s.remote", new_ref);
414                 git_config_set(key, tracking.remote ?  tracking.remote : ".");
415                 sprintf(key, "branch.%s.merge", new_ref);
416                 git_config_set(key, tracking.src);
417                 free(tracking.src);
418                 printf("Branch %s set up to track remote branch %s.\n",
419                                new_ref, orig_ref);
420         }
421
422         return 0;
423 }
424
425 static void create_branch(const char *name, const char *start_name,
426                           int force, int reflog, int track)
427 {
428         struct ref_lock *lock;
429         struct commit *commit;
430         unsigned char sha1[20];
431         char *real_ref, ref[PATH_MAX], msg[PATH_MAX + 20];
432         int forcing = 0;
433
434         snprintf(ref, sizeof ref, "refs/heads/%s", name);
435         if (check_ref_format(ref))
436                 die("'%s' is not a valid branch name.", name);
437
438         if (resolve_ref(ref, sha1, 1, NULL)) {
439                 if (!force)
440                         die("A branch named '%s' already exists.", name);
441                 else if (!is_bare_repository() && !strcmp(head, name))
442                         die("Cannot force update the current branch.");
443                 forcing = 1;
444         }
445
446         real_ref = NULL;
447         if (get_sha1(start_name, sha1))
448                 die("Not a valid object name: '%s'.", start_name);
449
450         switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
451         case 0:
452                 /* Not branching from any existing branch */
453                 real_ref = NULL;
454                 break;
455         case 1:
456                 /* Unique completion -- good */
457                 break;
458         default:
459                 die("Ambiguous object name: '%s'.", start_name);
460                 break;
461         }
462
463         if ((commit = lookup_commit_reference(sha1)) == NULL)
464                 die("Not a valid branch point: '%s'.", start_name);
465         hashcpy(sha1, commit->object.sha1);
466
467         lock = lock_any_ref_for_update(ref, NULL, 0);
468         if (!lock)
469                 die("Failed to lock ref for update: %s.", strerror(errno));
470
471         if (reflog)
472                 log_all_ref_updates = 1;
473
474         if (forcing)
475                 snprintf(msg, sizeof msg, "branch: Reset from %s",
476                          start_name);
477         else
478                 snprintf(msg, sizeof msg, "branch: Created from %s",
479                          start_name);
480
481         /* When branching off a remote branch, set up so that git-pull
482            automatically merges from there.  So far, this is only done for
483            remotes registered via .git/config.  */
484         if (real_ref && track)
485                 setup_tracking(name, real_ref);
486
487         if (write_ref_sha1(lock, sha1, msg) < 0)
488                 die("Failed to write ref: %s.", strerror(errno));
489
490         if (real_ref)
491                 free(real_ref);
492 }
493
494 static void rename_branch(const char *oldname, const char *newname, int force)
495 {
496         char oldref[PATH_MAX], newref[PATH_MAX], logmsg[PATH_MAX*2 + 100];
497         unsigned char sha1[20];
498         char oldsection[PATH_MAX], newsection[PATH_MAX];
499
500         if (!oldname)
501                 die("cannot rename the current branch while not on any.");
502
503         if (snprintf(oldref, sizeof(oldref), "refs/heads/%s", oldname) > sizeof(oldref))
504                 die("Old branchname too long");
505
506         if (check_ref_format(oldref))
507                 die("Invalid branch name: %s", oldref);
508
509         if (snprintf(newref, sizeof(newref), "refs/heads/%s", newname) > sizeof(newref))
510                 die("New branchname too long");
511
512         if (check_ref_format(newref))
513                 die("Invalid branch name: %s", newref);
514
515         if (resolve_ref(newref, sha1, 1, NULL) && !force)
516                 die("A branch named '%s' already exists.", newname);
517
518         snprintf(logmsg, sizeof(logmsg), "Branch: renamed %s to %s",
519                  oldref, newref);
520
521         if (rename_ref(oldref, newref, logmsg))
522                 die("Branch rename failed");
523
524         /* no need to pass logmsg here as HEAD didn't really move */
525         if (!strcmp(oldname, head) && create_symref("HEAD", newref, NULL))
526                 die("Branch renamed to %s, but HEAD is not updated!", newname);
527
528         snprintf(oldsection, sizeof(oldsection), "branch.%s", oldref + 11);
529         snprintf(newsection, sizeof(newsection), "branch.%s", newref + 11);
530         if (git_config_rename_section(oldsection, newsection) < 0)
531                 die("Branch is renamed, but update of config-file failed");
532 }
533
534 static int opt_parse_with_commit(const struct option *opt, const char *arg, int unset)
535 {
536         unsigned char sha1[20];
537         struct commit *commit;
538
539         if (!arg)
540                 return -1;
541         if (get_sha1(arg, sha1))
542                 die("malformed object name %s", arg);
543         commit = lookup_commit_reference(sha1);
544         if (!commit)
545                 die("no such commit %s", arg);
546         commit_list_insert(commit, opt->value);
547         return 0;
548 }
549
550 int cmd_branch(int argc, const char **argv, const char *prefix)
551 {
552         int delete = 0, rename = 0, force_create = 0;
553         int verbose = 0, abbrev = DEFAULT_ABBREV, detached = 0;
554         int reflog = 0, track;
555         int kinds = REF_LOCAL_BRANCH;
556         struct commit_list *with_commit = NULL;
557
558         struct option options[] = {
559                 OPT_GROUP("Generic options"),
560                 OPT__VERBOSE(&verbose),
561                 OPT_BOOLEAN( 0 , "track",  &track, "set up tracking mode (see git-pull(1))"),
562                 OPT_BOOLEAN( 0 , "color",  &branch_use_color, "use colored output"),
563                 OPT_SET_INT('r', NULL,     &kinds, "act on remote-tracking branches",
564                         REF_REMOTE_BRANCH),
565                 OPT_CALLBACK(0, "contains", &with_commit, "commit",
566                              "print only branches that contain the commit",
567                              opt_parse_with_commit),
568                 {
569                         OPTION_CALLBACK, 0, "with", &with_commit, "commit",
570                         "print only branches that contain the commit",
571                         PARSE_OPT_HIDDEN, opt_parse_with_commit,
572                 },
573                 OPT__ABBREV(&abbrev),
574
575                 OPT_GROUP("Specific git-branch actions:"),
576                 OPT_SET_INT('a', NULL, &kinds, "list both remote-tracking and local branches",
577                         REF_REMOTE_BRANCH | REF_LOCAL_BRANCH),
578                 OPT_BIT('d', NULL, &delete, "delete fully merged branch", 1),
579                 OPT_BIT('D', NULL, &delete, "delete branch (even if not merged)", 2),
580                 OPT_BIT('m', NULL, &rename, "move/rename a branch and its reflog", 1),
581                 OPT_BIT('M', NULL, &rename, "move/rename a branch, even if target exists", 2),
582                 OPT_BOOLEAN('l', NULL, &reflog, "create the branch's reflog"),
583                 OPT_BOOLEAN('f', NULL, &force_create, "force creation (when already exists)"),
584                 OPT_END(),
585         };
586
587         git_config(git_branch_config);
588         track = branch_track;
589         argc = parse_options(argc, argv, options, builtin_branch_usage, 0);
590         if (!!delete + !!rename + !!force_create > 1)
591                 usage_with_options(builtin_branch_usage, options);
592
593         head = resolve_ref("HEAD", head_sha1, 0, NULL);
594         if (!head)
595                 die("Failed to resolve HEAD as a valid ref.");
596         head = xstrdup(head);
597         if (!strcmp(head, "HEAD")) {
598                 detached = 1;
599         } else {
600                 if (prefixcmp(head, "refs/heads/"))
601                         die("HEAD not found below refs/heads!");
602                 head += 11;
603         }
604
605         if (delete)
606                 return delete_branches(argc, argv, delete > 1, kinds);
607         else if (argc == 0)
608                 print_ref_list(kinds, detached, verbose, abbrev, with_commit);
609         else if (rename && (argc == 1))
610                 rename_branch(head, argv[0], rename > 1);
611         else if (rename && (argc == 2))
612                 rename_branch(argv[0], argv[1], rename > 1);
613         else if (argc <= 2)
614                 create_branch(argv[0], (argc == 2) ? argv[1] : head,
615                               force_create, reflog, track);
616         else
617                 usage_with_options(builtin_branch_usage, options);
618
619         return 0;
620 }