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