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