Merge branch 'cb/t4210-illseq-auto-detect'
[git] / builtin / describe.c
1 #define USE_THE_INDEX_COMPATIBILITY_MACROS
2 #include "cache.h"
3 #include "config.h"
4 #include "lockfile.h"
5 #include "commit.h"
6 #include "tag.h"
7 #include "blob.h"
8 #include "refs.h"
9 #include "builtin.h"
10 #include "exec-cmd.h"
11 #include "parse-options.h"
12 #include "revision.h"
13 #include "diff.h"
14 #include "hashmap.h"
15 #include "argv-array.h"
16 #include "run-command.h"
17 #include "object-store.h"
18 #include "list-objects.h"
19 #include "commit-slab.h"
20
21 #define MAX_TAGS        (FLAG_BITS - 1)
22
23 define_commit_slab(commit_names, struct commit_name *);
24
25 static const char * const describe_usage[] = {
26         N_("git describe [<options>] [<commit-ish>...]"),
27         N_("git describe [<options>] --dirty"),
28         NULL
29 };
30
31 static int debug;       /* Display lots of verbose info */
32 static int all; /* Any valid ref can be used */
33 static int tags;        /* Allow lightweight tags */
34 static int longformat;
35 static int first_parent;
36 static int abbrev = -1; /* unspecified */
37 static int max_candidates = 10;
38 static struct hashmap names;
39 static int have_util;
40 static struct string_list patterns = STRING_LIST_INIT_NODUP;
41 static struct string_list exclude_patterns = STRING_LIST_INIT_NODUP;
42 static int always;
43 static const char *suffix, *dirty, *broken;
44 static struct commit_names commit_names;
45
46 /* diff-index command arguments to check if working tree is dirty. */
47 static const char *diff_index_args[] = {
48         "diff-index", "--quiet", "HEAD", "--", NULL
49 };
50
51 struct commit_name {
52         struct hashmap_entry entry;
53         struct object_id peeled;
54         struct tag *tag;
55         unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
56         unsigned name_checked:1;
57         unsigned misnamed:1;
58         struct object_id oid;
59         char *path;
60 };
61
62 static const char *prio_names[] = {
63         N_("head"), N_("lightweight"), N_("annotated"),
64 };
65
66 static int commit_name_neq(const void *unused_cmp_data,
67                            const struct hashmap_entry *eptr,
68                            const struct hashmap_entry *entry_or_key,
69                            const void *peeled)
70 {
71         const struct commit_name *cn1, *cn2;
72
73         cn1 = container_of(eptr, const struct commit_name, entry);
74         cn2 = container_of(entry_or_key, const struct commit_name, entry);
75
76         return !oideq(&cn1->peeled, peeled ? peeled : &cn2->peeled);
77 }
78
79 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
80 {
81         return hashmap_get_entry_from_hash(&names, oidhash(peeled), peeled,
82                                                 struct commit_name, entry);
83 }
84
85 static int replace_name(struct commit_name *e,
86                                int prio,
87                                const struct object_id *oid,
88                                struct tag **tag)
89 {
90         if (!e || e->prio < prio)
91                 return 1;
92
93         if (e->prio == 2 && prio == 2) {
94                 /* Multiple annotated tags point to the same commit.
95                  * Select one to keep based upon their tagger date.
96                  */
97                 struct tag *t;
98
99                 if (!e->tag) {
100                         t = lookup_tag(the_repository, &e->oid);
101                         if (!t || parse_tag(t))
102                                 return 1;
103                         e->tag = t;
104                 }
105
106                 t = lookup_tag(the_repository, oid);
107                 if (!t || parse_tag(t))
108                         return 0;
109                 *tag = t;
110
111                 if (e->tag->date < t->date)
112                         return 1;
113         }
114
115         return 0;
116 }
117
118 static void add_to_known_names(const char *path,
119                                const struct object_id *peeled,
120                                int prio,
121                                const struct object_id *oid)
122 {
123         struct commit_name *e = find_commit_name(peeled);
124         struct tag *tag = NULL;
125         if (replace_name(e, prio, oid, &tag)) {
126                 if (!e) {
127                         e = xmalloc(sizeof(struct commit_name));
128                         oidcpy(&e->peeled, peeled);
129                         hashmap_entry_init(&e->entry, oidhash(peeled));
130                         hashmap_add(&names, &e->entry);
131                         e->path = NULL;
132                 }
133                 e->tag = tag;
134                 e->prio = prio;
135                 e->name_checked = 0;
136                 e->misnamed = 0;
137                 oidcpy(&e->oid, oid);
138                 free(e->path);
139                 e->path = xstrdup(path);
140         }
141 }
142
143 static int get_name(const char *path, const struct object_id *oid, int flag, void *cb_data)
144 {
145         int is_tag = 0;
146         struct object_id peeled;
147         int is_annotated, prio;
148         const char *path_to_match = NULL;
149
150         if (skip_prefix(path, "refs/tags/", &path_to_match)) {
151                 is_tag = 1;
152         } else if (all) {
153                 if ((exclude_patterns.nr || patterns.nr) &&
154                     !skip_prefix(path, "refs/heads/", &path_to_match) &&
155                     !skip_prefix(path, "refs/remotes/", &path_to_match)) {
156                         /* Only accept reference of known type if there are match/exclude patterns */
157                         return 0;
158                 }
159         } else {
160                 /* Reject anything outside refs/tags/ unless --all */
161                 return 0;
162         }
163
164         /*
165          * If we're given exclude patterns, first exclude any tag which match
166          * any of the exclude pattern.
167          */
168         if (exclude_patterns.nr) {
169                 struct string_list_item *item;
170
171                 for_each_string_list_item(item, &exclude_patterns) {
172                         if (!wildmatch(item->string, path_to_match, 0))
173                                 return 0;
174                 }
175         }
176
177         /*
178          * If we're given patterns, accept only tags which match at least one
179          * pattern.
180          */
181         if (patterns.nr) {
182                 int found = 0;
183                 struct string_list_item *item;
184
185                 for_each_string_list_item(item, &patterns) {
186                         if (!wildmatch(item->string, path_to_match, 0)) {
187                                 found = 1;
188                                 break;
189                         }
190                 }
191
192                 if (!found)
193                         return 0;
194         }
195
196         /* Is it annotated? */
197         if (!peel_ref(path, &peeled)) {
198                 is_annotated = !oideq(oid, &peeled);
199         } else {
200                 oidcpy(&peeled, oid);
201                 is_annotated = 0;
202         }
203
204         /*
205          * By default, we only use annotated tags, but with --tags
206          * we fall back to lightweight ones (even without --tags,
207          * we still remember lightweight ones, only to give hints
208          * in an error message).  --all allows any refs to be used.
209          */
210         if (is_annotated)
211                 prio = 2;
212         else if (is_tag)
213                 prio = 1;
214         else
215                 prio = 0;
216
217         add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
218         return 0;
219 }
220
221 struct possible_tag {
222         struct commit_name *name;
223         int depth;
224         int found_order;
225         unsigned flag_within;
226 };
227
228 static int compare_pt(const void *a_, const void *b_)
229 {
230         struct possible_tag *a = (struct possible_tag *)a_;
231         struct possible_tag *b = (struct possible_tag *)b_;
232         if (a->depth != b->depth)
233                 return a->depth - b->depth;
234         if (a->found_order != b->found_order)
235                 return a->found_order - b->found_order;
236         return 0;
237 }
238
239 static unsigned long finish_depth_computation(
240         struct commit_list **list,
241         struct possible_tag *best)
242 {
243         unsigned long seen_commits = 0;
244         while (*list) {
245                 struct commit *c = pop_commit(list);
246                 struct commit_list *parents = c->parents;
247                 seen_commits++;
248                 if (c->object.flags & best->flag_within) {
249                         struct commit_list *a = *list;
250                         while (a) {
251                                 struct commit *i = a->item;
252                                 if (!(i->object.flags & best->flag_within))
253                                         break;
254                                 a = a->next;
255                         }
256                         if (!a)
257                                 break;
258                 } else
259                         best->depth++;
260                 while (parents) {
261                         struct commit *p = parents->item;
262                         parse_commit(p);
263                         if (!(p->object.flags & SEEN))
264                                 commit_list_insert_by_date(p, list);
265                         p->object.flags |= c->object.flags;
266                         parents = parents->next;
267                 }
268         }
269         return seen_commits;
270 }
271
272 static void append_name(struct commit_name *n, struct strbuf *dst)
273 {
274         if (n->prio == 2 && !n->tag) {
275                 n->tag = lookup_tag(the_repository, &n->oid);
276                 if (!n->tag || parse_tag(n->tag))
277                         die(_("annotated tag %s not available"), n->path);
278         }
279         if (n->tag && !n->name_checked) {
280                 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path)) {
281                         warning(_("tag '%s' is externally known as '%s'"),
282                                 n->path, n->tag->tag);
283                         n->misnamed = 1;
284                 }
285                 n->name_checked = 1;
286         }
287
288         if (n->tag) {
289                 if (all)
290                         strbuf_addstr(dst, "tags/");
291                 strbuf_addstr(dst, n->tag->tag);
292         } else {
293                 strbuf_addstr(dst, n->path);
294         }
295 }
296
297 static void append_suffix(int depth, const struct object_id *oid, struct strbuf *dst)
298 {
299         strbuf_addf(dst, "-%d-g%s", depth, find_unique_abbrev(oid, abbrev));
300 }
301
302 static void describe_commit(struct object_id *oid, struct strbuf *dst)
303 {
304         struct commit *cmit, *gave_up_on = NULL;
305         struct commit_list *list;
306         struct commit_name *n;
307         struct possible_tag all_matches[MAX_TAGS];
308         unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
309         unsigned long seen_commits = 0;
310         unsigned int unannotated_cnt = 0;
311
312         cmit = lookup_commit_reference(the_repository, oid);
313
314         n = find_commit_name(&cmit->object.oid);
315         if (n && (tags || all || n->prio == 2)) {
316                 /*
317                  * Exact match to an existing ref.
318                  */
319                 append_name(n, dst);
320                 if (n->misnamed || longformat)
321                         append_suffix(0, n->tag ? get_tagged_oid(n->tag) : oid, dst);
322                 if (suffix)
323                         strbuf_addstr(dst, suffix);
324                 return;
325         }
326
327         if (!max_candidates)
328                 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
329         if (debug)
330                 fprintf(stderr, _("No exact match on refs or tags, searching to describe\n"));
331
332         if (!have_util) {
333                 struct hashmap_iter iter;
334                 struct commit *c;
335                 struct commit_name *n;
336
337                 init_commit_names(&commit_names);
338                 hashmap_for_each_entry(&names, &iter, n,
339                                         entry /* member name */) {
340                         c = lookup_commit_reference_gently(the_repository,
341                                                            &n->peeled, 1);
342                         if (c)
343                                 *commit_names_at(&commit_names, c) = n;
344                 }
345                 have_util = 1;
346         }
347
348         list = NULL;
349         cmit->object.flags = SEEN;
350         commit_list_insert(cmit, &list);
351         while (list) {
352                 struct commit *c = pop_commit(&list);
353                 struct commit_list *parents = c->parents;
354                 struct commit_name **slot;
355
356                 seen_commits++;
357                 slot = commit_names_peek(&commit_names, c);
358                 n = slot ? *slot : NULL;
359                 if (n) {
360                         if (!tags && !all && n->prio < 2) {
361                                 unannotated_cnt++;
362                         } else if (match_cnt < max_candidates) {
363                                 struct possible_tag *t = &all_matches[match_cnt++];
364                                 t->name = n;
365                                 t->depth = seen_commits - 1;
366                                 t->flag_within = 1u << match_cnt;
367                                 t->found_order = match_cnt;
368                                 c->object.flags |= t->flag_within;
369                                 if (n->prio == 2)
370                                         annotated_cnt++;
371                         }
372                         else {
373                                 gave_up_on = c;
374                                 break;
375                         }
376                 }
377                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
378                         struct possible_tag *t = &all_matches[cur_match];
379                         if (!(c->object.flags & t->flag_within))
380                                 t->depth++;
381                 }
382                 /* Stop if last remaining path already covered by best candidate(s) */
383                 if (annotated_cnt && !list) {
384                         int best_depth = INT_MAX;
385                         unsigned best_within = 0;
386                         for (cur_match = 0; cur_match < match_cnt; cur_match++) {
387                                 struct possible_tag *t = &all_matches[cur_match];
388                                 if (t->depth < best_depth) {
389                                         best_depth = t->depth;
390                                         best_within = t->flag_within;
391                                 } else if (t->depth == best_depth) {
392                                         best_within |= t->flag_within;
393                                 }
394                         }
395                         if ((c->object.flags & best_within) == best_within) {
396                                 if (debug)
397                                         fprintf(stderr, _("finished search at %s\n"),
398                                                 oid_to_hex(&c->object.oid));
399                                 break;
400                         }
401                 }
402                 while (parents) {
403                         struct commit *p = parents->item;
404                         parse_commit(p);
405                         if (!(p->object.flags & SEEN))
406                                 commit_list_insert_by_date(p, &list);
407                         p->object.flags |= c->object.flags;
408                         parents = parents->next;
409
410                         if (first_parent)
411                                 break;
412                 }
413         }
414
415         if (!match_cnt) {
416                 struct object_id *cmit_oid = &cmit->object.oid;
417                 if (always) {
418                         strbuf_add_unique_abbrev(dst, cmit_oid, abbrev);
419                         if (suffix)
420                                 strbuf_addstr(dst, suffix);
421                         return;
422                 }
423                 if (unannotated_cnt)
424                         die(_("No annotated tags can describe '%s'.\n"
425                             "However, there were unannotated tags: try --tags."),
426                             oid_to_hex(cmit_oid));
427                 else
428                         die(_("No tags can describe '%s'.\n"
429                             "Try --always, or create some tags."),
430                             oid_to_hex(cmit_oid));
431         }
432
433         QSORT(all_matches, match_cnt, compare_pt);
434
435         if (gave_up_on) {
436                 commit_list_insert_by_date(gave_up_on, &list);
437                 seen_commits--;
438         }
439         seen_commits += finish_depth_computation(&list, &all_matches[0]);
440         free_commit_list(list);
441
442         if (debug) {
443                 static int label_width = -1;
444                 if (label_width < 0) {
445                         int i, w;
446                         for (i = 0; i < ARRAY_SIZE(prio_names); i++) {
447                                 w = strlen(_(prio_names[i]));
448                                 if (label_width < w)
449                                         label_width = w;
450                         }
451                 }
452                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
453                         struct possible_tag *t = &all_matches[cur_match];
454                         fprintf(stderr, " %-*s %8d %s\n",
455                                 label_width, _(prio_names[t->name->prio]),
456                                 t->depth, t->name->path);
457                 }
458                 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
459                 if (gave_up_on) {
460                         fprintf(stderr,
461                                 _("more than %i tags found; listed %i most recent\n"
462                                 "gave up search at %s\n"),
463                                 max_candidates, max_candidates,
464                                 oid_to_hex(&gave_up_on->object.oid));
465                 }
466         }
467
468         append_name(all_matches[0].name, dst);
469         if (all_matches[0].name->misnamed || abbrev)
470                 append_suffix(all_matches[0].depth, &cmit->object.oid, dst);
471         if (suffix)
472                 strbuf_addstr(dst, suffix);
473 }
474
475 struct process_commit_data {
476         struct object_id current_commit;
477         struct object_id looking_for;
478         struct strbuf *dst;
479         struct rev_info *revs;
480 };
481
482 static void process_commit(struct commit *commit, void *data)
483 {
484         struct process_commit_data *pcd = data;
485         pcd->current_commit = commit->object.oid;
486 }
487
488 static void process_object(struct object *obj, const char *path, void *data)
489 {
490         struct process_commit_data *pcd = data;
491
492         if (oideq(&pcd->looking_for, &obj->oid) && !pcd->dst->len) {
493                 reset_revision_walk();
494                 describe_commit(&pcd->current_commit, pcd->dst);
495                 strbuf_addf(pcd->dst, ":%s", path);
496                 free_commit_list(pcd->revs->commits);
497                 pcd->revs->commits = NULL;
498         }
499 }
500
501 static void describe_blob(struct object_id oid, struct strbuf *dst)
502 {
503         struct rev_info revs;
504         struct argv_array args = ARGV_ARRAY_INIT;
505         struct process_commit_data pcd = { null_oid, oid, dst, &revs};
506
507         argv_array_pushl(&args, "internal: The first arg is not parsed",
508                 "--objects", "--in-commit-order", "--reverse", "HEAD",
509                 NULL);
510
511         repo_init_revisions(the_repository, &revs, NULL);
512         if (setup_revisions(args.argc, args.argv, &revs, NULL) > 1)
513                 BUG("setup_revisions could not handle all args?");
514
515         if (prepare_revision_walk(&revs))
516                 die("revision walk setup failed");
517
518         traverse_commit_list(&revs, process_commit, process_object, &pcd);
519         reset_revision_walk();
520 }
521
522 static void describe(const char *arg, int last_one)
523 {
524         struct object_id oid;
525         struct commit *cmit;
526         struct strbuf sb = STRBUF_INIT;
527
528         if (debug)
529                 fprintf(stderr, _("describe %s\n"), arg);
530
531         if (get_oid(arg, &oid))
532                 die(_("Not a valid object name %s"), arg);
533         cmit = lookup_commit_reference_gently(the_repository, &oid, 1);
534
535         if (cmit)
536                 describe_commit(&oid, &sb);
537         else if (oid_object_info(the_repository, &oid, NULL) == OBJ_BLOB)
538                 describe_blob(oid, &sb);
539         else
540                 die(_("%s is neither a commit nor blob"), arg);
541
542         puts(sb.buf);
543
544         if (!last_one)
545                 clear_commit_marks(cmit, -1);
546
547         strbuf_release(&sb);
548 }
549
550 int cmd_describe(int argc, const char **argv, const char *prefix)
551 {
552         int contains = 0;
553         struct option options[] = {
554                 OPT_BOOL(0, "contains",   &contains, N_("find the tag that comes after the commit")),
555                 OPT_BOOL(0, "debug",      &debug, N_("debug search strategy on stderr")),
556                 OPT_BOOL(0, "all",        &all, N_("use any ref")),
557                 OPT_BOOL(0, "tags",       &tags, N_("use any tag, even unannotated")),
558                 OPT_BOOL(0, "long",       &longformat, N_("always use long format")),
559                 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
560                 OPT__ABBREV(&abbrev),
561                 OPT_SET_INT(0, "exact-match", &max_candidates,
562                             N_("only output exact matches"), 0),
563                 OPT_INTEGER(0, "candidates", &max_candidates,
564                             N_("consider <n> most recent tags (default: 10)")),
565                 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
566                            N_("only consider tags matching <pattern>")),
567                 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
568                            N_("do not consider tags matching <pattern>")),
569                 OPT_BOOL(0, "always",        &always,
570                         N_("show abbreviated commit object as fallback")),
571                 {OPTION_STRING, 0, "dirty",  &dirty, N_("mark"),
572                         N_("append <mark> on dirty working tree (default: \"-dirty\")"),
573                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
574                 {OPTION_STRING, 0, "broken",  &broken, N_("mark"),
575                         N_("append <mark> on broken working tree (default: \"-broken\")"),
576                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
577                 OPT_END(),
578         };
579
580         git_config(git_default_config, NULL);
581         argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
582         if (abbrev < 0)
583                 abbrev = DEFAULT_ABBREV;
584
585         if (max_candidates < 0)
586                 max_candidates = 0;
587         else if (max_candidates > MAX_TAGS)
588                 max_candidates = MAX_TAGS;
589
590         save_commit_buffer = 0;
591
592         if (longformat && abbrev == 0)
593                 die(_("--long is incompatible with --abbrev=0"));
594
595         if (contains) {
596                 struct string_list_item *item;
597                 struct argv_array args;
598
599                 argv_array_init(&args);
600                 argv_array_pushl(&args, "name-rev",
601                                  "--peel-tag", "--name-only", "--no-undefined",
602                                  NULL);
603                 if (always)
604                         argv_array_push(&args, "--always");
605                 if (!all) {
606                         argv_array_push(&args, "--tags");
607                         for_each_string_list_item(item, &patterns)
608                                 argv_array_pushf(&args, "--refs=refs/tags/%s", item->string);
609                         for_each_string_list_item(item, &exclude_patterns)
610                                 argv_array_pushf(&args, "--exclude=refs/tags/%s", item->string);
611                 }
612                 if (argc)
613                         argv_array_pushv(&args, argv);
614                 else
615                         argv_array_push(&args, "HEAD");
616                 return cmd_name_rev(args.argc, args.argv, prefix);
617         }
618
619         hashmap_init(&names, commit_name_neq, NULL, 0);
620         for_each_rawref(get_name, NULL);
621         if (!hashmap_get_size(&names) && !always)
622                 die(_("No names found, cannot describe anything."));
623
624         if (argc == 0) {
625                 if (broken) {
626                         struct child_process cp = CHILD_PROCESS_INIT;
627                         argv_array_pushv(&cp.args, diff_index_args);
628                         cp.git_cmd = 1;
629                         cp.no_stdin = 1;
630                         cp.no_stdout = 1;
631
632                         if (!dirty)
633                                 dirty = "-dirty";
634
635                         switch (run_command(&cp)) {
636                         case 0:
637                                 suffix = NULL;
638                                 break;
639                         case 1:
640                                 suffix = dirty;
641                                 break;
642                         default:
643                                 /* diff-index aborted abnormally */
644                                 suffix = broken;
645                         }
646                 } else if (dirty) {
647                         struct lock_file index_lock = LOCK_INIT;
648                         struct rev_info revs;
649                         struct argv_array args = ARGV_ARRAY_INIT;
650                         int fd, result;
651
652                         setup_work_tree();
653                         read_cache();
654                         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
655                                       NULL, NULL, NULL);
656                         fd = hold_locked_index(&index_lock, 0);
657                         if (0 <= fd)
658                                 repo_update_index_if_able(the_repository, &index_lock);
659
660                         repo_init_revisions(the_repository, &revs, prefix);
661                         argv_array_pushv(&args, diff_index_args);
662                         if (setup_revisions(args.argc, args.argv, &revs, NULL) != 1)
663                                 BUG("malformed internal diff-index command line");
664                         result = run_diff_index(&revs, 0);
665
666                         if (!diff_result_code(&revs.diffopt, result))
667                                 suffix = NULL;
668                         else
669                                 suffix = dirty;
670                 }
671                 describe("HEAD", 1);
672         } else if (dirty) {
673                 die(_("--dirty is incompatible with commit-ishes"));
674         } else if (broken) {
675                 die(_("--broken is incompatible with commit-ishes"));
676         } else {
677                 while (argc-- > 0)
678                         describe(*argv++, argc == 0);
679         }
680         return 0;
681 }