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