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