Merge branch 'em/status-rename-config'
[git] / builtin / describe.c
1 #include "cache.h"
2 #include "config.h"
3 #include "lockfile.h"
4 #include "commit.h"
5 #include "tag.h"
6 #include "blob.h"
7 #include "refs.h"
8 #include "builtin.h"
9 #include "exec-cmd.h"
10 #include "parse-options.h"
11 #include "revision.h"
12 #include "diff.h"
13 #include "hashmap.h"
14 #include "argv-array.h"
15 #include "run-command.h"
16 #include "revision.h"
17 #include "list-objects.h"
18
19 #define MAX_TAGS        (FLAG_BITS - 1)
20
21 static const char * const describe_usage[] = {
22         N_("git describe [<options>] [<commit-ish>...]"),
23         N_("git describe [<options>] --dirty"),
24         NULL
25 };
26
27 static int debug;       /* Display lots of verbose info */
28 static int all; /* Any valid ref can be used */
29 static int tags;        /* Allow lightweight tags */
30 static int longformat;
31 static int first_parent;
32 static int abbrev = -1; /* unspecified */
33 static int max_candidates = 10;
34 static struct hashmap names;
35 static int have_util;
36 static struct string_list patterns = STRING_LIST_INIT_NODUP;
37 static struct string_list exclude_patterns = STRING_LIST_INIT_NODUP;
38 static int always;
39 static const char *suffix, *dirty, *broken;
40
41 /* diff-index command arguments to check if working tree is dirty. */
42 static const char *diff_index_args[] = {
43         "diff-index", "--quiet", "HEAD", "--", NULL
44 };
45
46 struct commit_name {
47         struct hashmap_entry entry;
48         struct object_id peeled;
49         struct tag *tag;
50         unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
51         unsigned name_checked:1;
52         struct object_id oid;
53         char *path;
54 };
55
56 static const char *prio_names[] = {
57         N_("head"), N_("lightweight"), N_("annotated"),
58 };
59
60 static int commit_name_cmp(const void *unused_cmp_data,
61                            const void *entry,
62                            const void *entry_or_key,
63                            const void *peeled)
64 {
65         const struct commit_name *cn1 = entry;
66         const struct commit_name *cn2 = entry_or_key;
67
68         return oidcmp(&cn1->peeled, peeled ? peeled : &cn2->peeled);
69 }
70
71 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
72 {
73         return hashmap_get_from_hash(&names, sha1hash(peeled->hash), peeled->hash);
74 }
75
76 static int replace_name(struct commit_name *e,
77                                int prio,
78                                const struct object_id *oid,
79                                struct tag **tag)
80 {
81         if (!e || e->prio < prio)
82                 return 1;
83
84         if (e->prio == 2 && prio == 2) {
85                 /* Multiple annotated tags point to the same commit.
86                  * Select one to keep based upon their tagger date.
87                  */
88                 struct tag *t;
89
90                 if (!e->tag) {
91                         t = lookup_tag(&e->oid);
92                         if (!t || parse_tag(t))
93                                 return 1;
94                         e->tag = t;
95                 }
96
97                 t = lookup_tag(oid);
98                 if (!t || parse_tag(t))
99                         return 0;
100                 *tag = t;
101
102                 if (e->tag->date < t->date)
103                         return 1;
104         }
105
106         return 0;
107 }
108
109 static void add_to_known_names(const char *path,
110                                const struct object_id *peeled,
111                                int prio,
112                                const struct object_id *oid)
113 {
114         struct commit_name *e = find_commit_name(peeled);
115         struct tag *tag = NULL;
116         if (replace_name(e, prio, oid, &tag)) {
117                 if (!e) {
118                         e = xmalloc(sizeof(struct commit_name));
119                         oidcpy(&e->peeled, peeled);
120                         hashmap_entry_init(e, sha1hash(peeled->hash));
121                         hashmap_add(&names, e);
122                         e->path = NULL;
123                 }
124                 e->tag = tag;
125                 e->prio = prio;
126                 e->name_checked = 0;
127                 oidcpy(&e->oid, oid);
128                 free(e->path);
129                 e->path = xstrdup(path);
130         }
131 }
132
133 static int get_name(const char *path, const struct object_id *oid, int flag, void *cb_data)
134 {
135         int is_tag = 0;
136         struct object_id peeled;
137         int is_annotated, prio;
138         const char *path_to_match = NULL;
139
140         if (skip_prefix(path, "refs/tags/", &path_to_match)) {
141                 is_tag = 1;
142         } else if (all) {
143                 if ((exclude_patterns.nr || patterns.nr) &&
144                     !skip_prefix(path, "refs/heads/", &path_to_match) &&
145                     !skip_prefix(path, "refs/remotes/", &path_to_match)) {
146                         /* Only accept reference of known type if there are match/exclude patterns */
147                         return 0;
148                 }
149         } else {
150                 /* Reject anything outside refs/tags/ unless --all */
151                 return 0;
152         }
153
154         /*
155          * If we're given exclude patterns, first exclude any tag which match
156          * any of the exclude pattern.
157          */
158         if (exclude_patterns.nr) {
159                 struct string_list_item *item;
160
161                 for_each_string_list_item(item, &exclude_patterns) {
162                         if (!wildmatch(item->string, path_to_match, 0))
163                                 return 0;
164                 }
165         }
166
167         /*
168          * If we're given patterns, accept only tags which match at least one
169          * pattern.
170          */
171         if (patterns.nr) {
172                 int found = 0;
173                 struct string_list_item *item;
174
175                 for_each_string_list_item(item, &patterns) {
176                         if (!wildmatch(item->string, path_to_match, 0)) {
177                                 found = 1;
178                                 break;
179                         }
180                 }
181
182                 if (!found)
183                         return 0;
184         }
185
186         /* Is it annotated? */
187         if (!peel_ref(path, &peeled)) {
188                 is_annotated = !!oidcmp(oid, &peeled);
189         } else {
190                 oidcpy(&peeled, oid);
191                 is_annotated = 0;
192         }
193
194         /*
195          * By default, we only use annotated tags, but with --tags
196          * we fall back to lightweight ones (even without --tags,
197          * we still remember lightweight ones, only to give hints
198          * in an error message).  --all allows any refs to be used.
199          */
200         if (is_annotated)
201                 prio = 2;
202         else if (is_tag)
203                 prio = 1;
204         else
205                 prio = 0;
206
207         add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
208         return 0;
209 }
210
211 struct possible_tag {
212         struct commit_name *name;
213         int depth;
214         int found_order;
215         unsigned flag_within;
216 };
217
218 static int compare_pt(const void *a_, const void *b_)
219 {
220         struct possible_tag *a = (struct possible_tag *)a_;
221         struct possible_tag *b = (struct possible_tag *)b_;
222         if (a->depth != b->depth)
223                 return a->depth - b->depth;
224         if (a->found_order != b->found_order)
225                 return a->found_order - b->found_order;
226         return 0;
227 }
228
229 static unsigned long finish_depth_computation(
230         struct commit_list **list,
231         struct possible_tag *best)
232 {
233         unsigned long seen_commits = 0;
234         while (*list) {
235                 struct commit *c = pop_commit(list);
236                 struct commit_list *parents = c->parents;
237                 seen_commits++;
238                 if (c->object.flags & best->flag_within) {
239                         struct commit_list *a = *list;
240                         while (a) {
241                                 struct commit *i = a->item;
242                                 if (!(i->object.flags & best->flag_within))
243                                         break;
244                                 a = a->next;
245                         }
246                         if (!a)
247                                 break;
248                 } else
249                         best->depth++;
250                 while (parents) {
251                         struct commit *p = parents->item;
252                         parse_commit(p);
253                         if (!(p->object.flags & SEEN))
254                                 commit_list_insert_by_date(p, list);
255                         p->object.flags |= c->object.flags;
256                         parents = parents->next;
257                 }
258         }
259         return seen_commits;
260 }
261
262 static void append_name(struct commit_name *n, struct strbuf *dst)
263 {
264         if (n->prio == 2 && !n->tag) {
265                 n->tag = lookup_tag(&n->oid);
266                 if (!n->tag || parse_tag(n->tag))
267                         die(_("annotated tag %s not available"), n->path);
268         }
269         if (n->tag && !n->name_checked) {
270                 if (!n->tag->tag)
271                         die(_("annotated tag %s has no embedded name"), n->path);
272                 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
273                         warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
274                 n->name_checked = 1;
275         }
276
277         if (n->tag) {
278                 if (all)
279                         strbuf_addstr(dst, "tags/");
280                 strbuf_addstr(dst, n->tag->tag);
281         } else {
282                 strbuf_addstr(dst, n->path);
283         }
284 }
285
286 static void append_suffix(int depth, const struct object_id *oid, struct strbuf *dst)
287 {
288         strbuf_addf(dst, "-%d-g%s", depth, find_unique_abbrev(oid, abbrev));
289 }
290
291 static void describe_commit(struct object_id *oid, struct strbuf *dst)
292 {
293         struct commit *cmit, *gave_up_on = NULL;
294         struct commit_list *list;
295         struct commit_name *n;
296         struct possible_tag all_matches[MAX_TAGS];
297         unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
298         unsigned long seen_commits = 0;
299         unsigned int unannotated_cnt = 0;
300
301         cmit = lookup_commit_reference(oid);
302
303         n = find_commit_name(&cmit->object.oid);
304         if (n && (tags || all || n->prio == 2)) {
305                 /*
306                  * Exact match to an existing ref.
307                  */
308                 append_name(n, dst);
309                 if (longformat)
310                         append_suffix(0, n->tag ? &n->tag->tagged->oid : oid, dst);
311                 if (suffix)
312                         strbuf_addstr(dst, suffix);
313                 return;
314         }
315
316         if (!max_candidates)
317                 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
318         if (debug)
319                 fprintf(stderr, _("No exact match on refs or tags, searching to describe\n"));
320
321         if (!have_util) {
322                 struct hashmap_iter iter;
323                 struct commit *c;
324                 struct commit_name *n = hashmap_iter_first(&names, &iter);
325                 for (; n; n = hashmap_iter_next(&iter)) {
326                         c = lookup_commit_reference_gently(&n->peeled, 1);
327                         if (c)
328                                 c->util = n;
329                 }
330                 have_util = 1;
331         }
332
333         list = NULL;
334         cmit->object.flags = SEEN;
335         commit_list_insert(cmit, &list);
336         while (list) {
337                 struct commit *c = pop_commit(&list);
338                 struct commit_list *parents = c->parents;
339                 seen_commits++;
340                 n = c->util;
341                 if (n) {
342                         if (!tags && !all && n->prio < 2) {
343                                 unannotated_cnt++;
344                         } else if (match_cnt < max_candidates) {
345                                 struct possible_tag *t = &all_matches[match_cnt++];
346                                 t->name = n;
347                                 t->depth = seen_commits - 1;
348                                 t->flag_within = 1u << match_cnt;
349                                 t->found_order = match_cnt;
350                                 c->object.flags |= t->flag_within;
351                                 if (n->prio == 2)
352                                         annotated_cnt++;
353                         }
354                         else {
355                                 gave_up_on = c;
356                                 break;
357                         }
358                 }
359                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
360                         struct possible_tag *t = &all_matches[cur_match];
361                         if (!(c->object.flags & t->flag_within))
362                                 t->depth++;
363                 }
364                 if (annotated_cnt && !list) {
365                         if (debug)
366                                 fprintf(stderr, _("finished search at %s\n"),
367                                         oid_to_hex(&c->object.oid));
368                         break;
369                 }
370                 while (parents) {
371                         struct commit *p = parents->item;
372                         parse_commit(p);
373                         if (!(p->object.flags & SEEN))
374                                 commit_list_insert_by_date(p, &list);
375                         p->object.flags |= c->object.flags;
376                         parents = parents->next;
377
378                         if (first_parent)
379                                 break;
380                 }
381         }
382
383         if (!match_cnt) {
384                 struct object_id *cmit_oid = &cmit->object.oid;
385                 if (always) {
386                         strbuf_add_unique_abbrev(dst, cmit_oid, abbrev);
387                         if (suffix)
388                                 strbuf_addstr(dst, suffix);
389                         return;
390                 }
391                 if (unannotated_cnt)
392                         die(_("No annotated tags can describe '%s'.\n"
393                             "However, there were unannotated tags: try --tags."),
394                             oid_to_hex(cmit_oid));
395                 else
396                         die(_("No tags can describe '%s'.\n"
397                             "Try --always, or create some tags."),
398                             oid_to_hex(cmit_oid));
399         }
400
401         QSORT(all_matches, match_cnt, compare_pt);
402
403         if (gave_up_on) {
404                 commit_list_insert_by_date(gave_up_on, &list);
405                 seen_commits--;
406         }
407         seen_commits += finish_depth_computation(&list, &all_matches[0]);
408         free_commit_list(list);
409
410         if (debug) {
411                 static int label_width = -1;
412                 if (label_width < 0) {
413                         int i, w;
414                         for (i = 0; i < ARRAY_SIZE(prio_names); i++) {
415                                 w = strlen(_(prio_names[i]));
416                                 if (label_width < w)
417                                         label_width = w;
418                         }
419                 }
420                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
421                         struct possible_tag *t = &all_matches[cur_match];
422                         fprintf(stderr, " %-*s %8d %s\n",
423                                 label_width, _(prio_names[t->name->prio]),
424                                 t->depth, t->name->path);
425                 }
426                 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
427                 if (gave_up_on) {
428                         fprintf(stderr,
429                                 _("more than %i tags found; listed %i most recent\n"
430                                 "gave up search at %s\n"),
431                                 max_candidates, max_candidates,
432                                 oid_to_hex(&gave_up_on->object.oid));
433                 }
434         }
435
436         append_name(all_matches[0].name, dst);
437         if (abbrev)
438                 append_suffix(all_matches[0].depth, &cmit->object.oid, dst);
439         if (suffix)
440                 strbuf_addstr(dst, suffix);
441 }
442
443 struct process_commit_data {
444         struct object_id current_commit;
445         struct object_id looking_for;
446         struct strbuf *dst;
447         struct rev_info *revs;
448 };
449
450 static void process_commit(struct commit *commit, void *data)
451 {
452         struct process_commit_data *pcd = data;
453         pcd->current_commit = commit->object.oid;
454 }
455
456 static void process_object(struct object *obj, const char *path, void *data)
457 {
458         struct process_commit_data *pcd = data;
459
460         if (!oidcmp(&pcd->looking_for, &obj->oid) && !pcd->dst->len) {
461                 reset_revision_walk();
462                 describe_commit(&pcd->current_commit, pcd->dst);
463                 strbuf_addf(pcd->dst, ":%s", path);
464                 free_commit_list(pcd->revs->commits);
465                 pcd->revs->commits = NULL;
466         }
467 }
468
469 static void describe_blob(struct object_id oid, struct strbuf *dst)
470 {
471         struct rev_info revs;
472         struct argv_array args = ARGV_ARRAY_INIT;
473         struct process_commit_data pcd = { null_oid, oid, dst, &revs};
474
475         argv_array_pushl(&args, "internal: The first arg is not parsed",
476                 "--objects", "--in-commit-order", "--reverse", "HEAD",
477                 NULL);
478
479         init_revisions(&revs, NULL);
480         if (setup_revisions(args.argc, args.argv, &revs, NULL) > 1)
481                 BUG("setup_revisions could not handle all args?");
482
483         if (prepare_revision_walk(&revs))
484                 die("revision walk setup failed");
485
486         traverse_commit_list(&revs, process_commit, process_object, &pcd);
487         reset_revision_walk();
488 }
489
490 static void describe(const char *arg, int last_one)
491 {
492         struct object_id oid;
493         struct commit *cmit;
494         struct strbuf sb = STRBUF_INIT;
495
496         if (debug)
497                 fprintf(stderr, _("describe %s\n"), arg);
498
499         if (get_oid(arg, &oid))
500                 die(_("Not a valid object name %s"), arg);
501         cmit = lookup_commit_reference_gently(&oid, 1);
502
503         if (cmit)
504                 describe_commit(&oid, &sb);
505         else if (oid_object_info(the_repository, &oid, NULL) == OBJ_BLOB)
506                 describe_blob(oid, &sb);
507         else
508                 die(_("%s is neither a commit nor blob"), arg);
509
510         puts(sb.buf);
511
512         if (!last_one)
513                 clear_commit_marks(cmit, -1);
514
515         strbuf_release(&sb);
516 }
517
518 int cmd_describe(int argc, const char **argv, const char *prefix)
519 {
520         int contains = 0;
521         struct option options[] = {
522                 OPT_BOOL(0, "contains",   &contains, N_("find the tag that comes after the commit")),
523                 OPT_BOOL(0, "debug",      &debug, N_("debug search strategy on stderr")),
524                 OPT_BOOL(0, "all",        &all, N_("use any ref")),
525                 OPT_BOOL(0, "tags",       &tags, N_("use any tag, even unannotated")),
526                 OPT_BOOL(0, "long",       &longformat, N_("always use long format")),
527                 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
528                 OPT__ABBREV(&abbrev),
529                 OPT_SET_INT(0, "exact-match", &max_candidates,
530                             N_("only output exact matches"), 0),
531                 OPT_INTEGER(0, "candidates", &max_candidates,
532                             N_("consider <n> most recent tags (default: 10)")),
533                 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
534                            N_("only consider tags matching <pattern>")),
535                 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
536                            N_("do not consider tags matching <pattern>")),
537                 OPT_BOOL(0, "always",        &always,
538                         N_("show abbreviated commit object as fallback")),
539                 {OPTION_STRING, 0, "dirty",  &dirty, N_("mark"),
540                         N_("append <mark> on dirty working tree (default: \"-dirty\")"),
541                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
542                 {OPTION_STRING, 0, "broken",  &broken, N_("mark"),
543                         N_("append <mark> on broken working tree (default: \"-broken\")"),
544                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
545                 OPT_END(),
546         };
547
548         git_config(git_default_config, NULL);
549         argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
550         if (abbrev < 0)
551                 abbrev = DEFAULT_ABBREV;
552
553         if (max_candidates < 0)
554                 max_candidates = 0;
555         else if (max_candidates > MAX_TAGS)
556                 max_candidates = MAX_TAGS;
557
558         save_commit_buffer = 0;
559
560         if (longformat && abbrev == 0)
561                 die(_("--long is incompatible with --abbrev=0"));
562
563         if (contains) {
564                 struct string_list_item *item;
565                 struct argv_array args;
566
567                 argv_array_init(&args);
568                 argv_array_pushl(&args, "name-rev",
569                                  "--peel-tag", "--name-only", "--no-undefined",
570                                  NULL);
571                 if (always)
572                         argv_array_push(&args, "--always");
573                 if (!all) {
574                         argv_array_push(&args, "--tags");
575                         for_each_string_list_item(item, &patterns)
576                                 argv_array_pushf(&args, "--refs=refs/tags/%s", item->string);
577                         for_each_string_list_item(item, &exclude_patterns)
578                                 argv_array_pushf(&args, "--exclude=refs/tags/%s", item->string);
579                 }
580                 if (argc)
581                         argv_array_pushv(&args, argv);
582                 else
583                         argv_array_push(&args, "HEAD");
584                 return cmd_name_rev(args.argc, args.argv, prefix);
585         }
586
587         hashmap_init(&names, commit_name_cmp, NULL, 0);
588         for_each_rawref(get_name, NULL);
589         if (!hashmap_get_size(&names) && !always)
590                 die(_("No names found, cannot describe anything."));
591
592         if (argc == 0) {
593                 if (broken) {
594                         struct child_process cp = CHILD_PROCESS_INIT;
595                         argv_array_pushv(&cp.args, diff_index_args);
596                         cp.git_cmd = 1;
597                         cp.no_stdin = 1;
598                         cp.no_stdout = 1;
599
600                         if (!dirty)
601                                 dirty = "-dirty";
602
603                         switch (run_command(&cp)) {
604                         case 0:
605                                 suffix = NULL;
606                                 break;
607                         case 1:
608                                 suffix = dirty;
609                                 break;
610                         default:
611                                 /* diff-index aborted abnormally */
612                                 suffix = broken;
613                         }
614                 } else if (dirty) {
615                         static struct lock_file index_lock;
616                         struct rev_info revs;
617                         struct argv_array args = ARGV_ARRAY_INIT;
618                         int fd, result;
619
620                         read_cache_preload(NULL);
621                         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
622                                       NULL, NULL, NULL);
623                         fd = hold_locked_index(&index_lock, 0);
624                         if (0 <= fd)
625                                 update_index_if_able(&the_index, &index_lock);
626
627                         init_revisions(&revs, prefix);
628                         argv_array_pushv(&args, diff_index_args);
629                         if (setup_revisions(args.argc, args.argv, &revs, NULL) != 1)
630                                 BUG("malformed internal diff-index command line");
631                         result = run_diff_index(&revs, 0);
632
633                         if (!diff_result_code(&revs.diffopt, result))
634                                 suffix = NULL;
635                         else
636                                 suffix = dirty;
637                 }
638                 describe("HEAD", 1);
639         } else if (dirty) {
640                 die(_("--dirty is incompatible with commit-ishes"));
641         } else if (broken) {
642                 die(_("--broken is incompatible with commit-ishes"));
643         } else {
644                 while (argc-- > 0)
645                         describe(*argv++, argc == 0);
646         }
647         return 0;
648 }