Merge branch 'js/win32-lazyload-dll'
[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 void *entry,
59                            const void *entry_or_key,
60                            const void *peeled)
61 {
62         const struct commit_name *cn1 = entry;
63         const struct commit_name *cn2 = entry_or_key;
64
65         return oidcmp(&cn1->peeled, peeled ? peeled : &cn2->peeled);
66 }
67
68 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
69 {
70         return hashmap_get_from_hash(&names, sha1hash(peeled->hash), peeled->hash);
71 }
72
73 static int replace_name(struct commit_name *e,
74                                int prio,
75                                const struct object_id *oid,
76                                struct tag **tag)
77 {
78         if (!e || e->prio < prio)
79                 return 1;
80
81         if (e->prio == 2 && prio == 2) {
82                 /* Multiple annotated tags point to the same commit.
83                  * Select one to keep based upon their tagger date.
84                  */
85                 struct tag *t;
86
87                 if (!e->tag) {
88                         t = lookup_tag(&e->oid);
89                         if (!t || parse_tag(t))
90                                 return 1;
91                         e->tag = t;
92                 }
93
94                 t = lookup_tag(oid);
95                 if (!t || parse_tag(t))
96                         return 0;
97                 *tag = t;
98
99                 if (e->tag->date < t->date)
100                         return 1;
101         }
102
103         return 0;
104 }
105
106 static void add_to_known_names(const char *path,
107                                const struct object_id *peeled,
108                                int prio,
109                                const struct object_id *oid)
110 {
111         struct commit_name *e = find_commit_name(peeled);
112         struct tag *tag = NULL;
113         if (replace_name(e, prio, oid, &tag)) {
114                 if (!e) {
115                         e = xmalloc(sizeof(struct commit_name));
116                         oidcpy(&e->peeled, peeled);
117                         hashmap_entry_init(e, sha1hash(peeled->hash));
118                         hashmap_add(&names, e);
119                         e->path = NULL;
120                 }
121                 e->tag = tag;
122                 e->prio = prio;
123                 e->name_checked = 0;
124                 oidcpy(&e->oid, oid);
125                 free(e->path);
126                 e->path = xstrdup(path);
127         }
128 }
129
130 static int get_name(const char *path, const struct object_id *oid, int flag, void *cb_data)
131 {
132         int is_tag = starts_with(path, "refs/tags/");
133         struct object_id peeled;
134         int is_annotated, prio;
135
136         /* Reject anything outside refs/tags/ unless --all */
137         if (!all && !is_tag)
138                 return 0;
139
140         /*
141          * If we're given exclude patterns, first exclude any tag which match
142          * any of the exclude pattern.
143          */
144         if (exclude_patterns.nr) {
145                 struct string_list_item *item;
146
147                 if (!is_tag)
148                         return 0;
149
150                 for_each_string_list_item(item, &exclude_patterns) {
151                         if (!wildmatch(item->string, path + 10, 0))
152                                 return 0;
153                 }
154         }
155
156         /*
157          * If we're given patterns, accept only tags which match at least one
158          * pattern.
159          */
160         if (patterns.nr) {
161                 int found = 0;
162                 struct string_list_item *item;
163
164                 if (!is_tag)
165                         return 0;
166
167                 for_each_string_list_item(item, &patterns) {
168                         if (!wildmatch(item->string, path + 10, 0)) {
169                                 found = 1;
170                                 break;
171                         }
172                 }
173
174                 if (!found)
175                         return 0;
176         }
177
178         /* Is it annotated? */
179         if (!peel_ref(path, peeled.hash)) {
180                 is_annotated = !!oidcmp(oid, &peeled);
181         } else {
182                 oidcpy(&peeled, oid);
183                 is_annotated = 0;
184         }
185
186         /*
187          * By default, we only use annotated tags, but with --tags
188          * we fall back to lightweight ones (even without --tags,
189          * we still remember lightweight ones, only to give hints
190          * in an error message).  --all allows any refs to be used.
191          */
192         if (is_annotated)
193                 prio = 2;
194         else if (is_tag)
195                 prio = 1;
196         else
197                 prio = 0;
198
199         add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
200         return 0;
201 }
202
203 struct possible_tag {
204         struct commit_name *name;
205         int depth;
206         int found_order;
207         unsigned flag_within;
208 };
209
210 static int compare_pt(const void *a_, const void *b_)
211 {
212         struct possible_tag *a = (struct possible_tag *)a_;
213         struct possible_tag *b = (struct possible_tag *)b_;
214         if (a->depth != b->depth)
215                 return a->depth - b->depth;
216         if (a->found_order != b->found_order)
217                 return a->found_order - b->found_order;
218         return 0;
219 }
220
221 static unsigned long finish_depth_computation(
222         struct commit_list **list,
223         struct possible_tag *best)
224 {
225         unsigned long seen_commits = 0;
226         while (*list) {
227                 struct commit *c = pop_commit(list);
228                 struct commit_list *parents = c->parents;
229                 seen_commits++;
230                 if (c->object.flags & best->flag_within) {
231                         struct commit_list *a = *list;
232                         while (a) {
233                                 struct commit *i = a->item;
234                                 if (!(i->object.flags & best->flag_within))
235                                         break;
236                                 a = a->next;
237                         }
238                         if (!a)
239                                 break;
240                 } else
241                         best->depth++;
242                 while (parents) {
243                         struct commit *p = parents->item;
244                         parse_commit(p);
245                         if (!(p->object.flags & SEEN))
246                                 commit_list_insert_by_date(p, list);
247                         p->object.flags |= c->object.flags;
248                         parents = parents->next;
249                 }
250         }
251         return seen_commits;
252 }
253
254 static void display_name(struct commit_name *n)
255 {
256         if (n->prio == 2 && !n->tag) {
257                 n->tag = lookup_tag(&n->oid);
258                 if (!n->tag || parse_tag(n->tag))
259                         die(_("annotated tag %s not available"), n->path);
260         }
261         if (n->tag && !n->name_checked) {
262                 if (!n->tag->tag)
263                         die(_("annotated tag %s has no embedded name"), n->path);
264                 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
265                         warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
266                 n->name_checked = 1;
267         }
268
269         if (n->tag)
270                 printf("%s", n->tag->tag);
271         else
272                 printf("%s", n->path);
273 }
274
275 static void show_suffix(int depth, const struct object_id *oid)
276 {
277         printf("-%d-g%s", depth, find_unique_abbrev(oid->hash, abbrev));
278 }
279
280 static void describe(const char *arg, int last_one)
281 {
282         struct object_id oid;
283         struct commit *cmit, *gave_up_on = NULL;
284         struct commit_list *list;
285         struct commit_name *n;
286         struct possible_tag all_matches[MAX_TAGS];
287         unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
288         unsigned long seen_commits = 0;
289         unsigned int unannotated_cnt = 0;
290
291         if (get_oid(arg, &oid))
292                 die(_("Not a valid object name %s"), arg);
293         cmit = lookup_commit_reference(&oid);
294         if (!cmit)
295                 die(_("%s is not a valid '%s' object"), arg, commit_type);
296
297         n = find_commit_name(&cmit->object.oid);
298         if (n && (tags || all || n->prio == 2)) {
299                 /*
300                  * Exact match to an existing ref.
301                  */
302                 display_name(n);
303                 if (longformat)
304                         show_suffix(0, n->tag ? &n->tag->tagged->oid : &oid);
305                 if (suffix)
306                         printf("%s", suffix);
307                 printf("\n");
308                 return;
309         }
310
311         if (!max_candidates)
312                 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
313         if (debug)
314                 fprintf(stderr, _("searching to describe %s\n"), arg);
315
316         if (!have_util) {
317                 struct hashmap_iter iter;
318                 struct commit *c;
319                 struct commit_name *n = hashmap_iter_first(&names, &iter);
320                 for (; n; n = hashmap_iter_next(&iter)) {
321                         c = lookup_commit_reference_gently(&n->peeled, 1);
322                         if (c)
323                                 c->util = n;
324                 }
325                 have_util = 1;
326         }
327
328         list = NULL;
329         cmit->object.flags = SEEN;
330         commit_list_insert(cmit, &list);
331         while (list) {
332                 struct commit *c = pop_commit(&list);
333                 struct commit_list *parents = c->parents;
334                 seen_commits++;
335                 n = c->util;
336                 if (n) {
337                         if (!tags && !all && n->prio < 2) {
338                                 unannotated_cnt++;
339                         } else if (match_cnt < max_candidates) {
340                                 struct possible_tag *t = &all_matches[match_cnt++];
341                                 t->name = n;
342                                 t->depth = seen_commits - 1;
343                                 t->flag_within = 1u << match_cnt;
344                                 t->found_order = match_cnt;
345                                 c->object.flags |= t->flag_within;
346                                 if (n->prio == 2)
347                                         annotated_cnt++;
348                         }
349                         else {
350                                 gave_up_on = c;
351                                 break;
352                         }
353                 }
354                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
355                         struct possible_tag *t = &all_matches[cur_match];
356                         if (!(c->object.flags & t->flag_within))
357                                 t->depth++;
358                 }
359                 if (annotated_cnt && !list) {
360                         if (debug)
361                                 fprintf(stderr, _("finished search at %s\n"),
362                                         oid_to_hex(&c->object.oid));
363                         break;
364                 }
365                 while (parents) {
366                         struct commit *p = parents->item;
367                         parse_commit(p);
368                         if (!(p->object.flags & SEEN))
369                                 commit_list_insert_by_date(p, &list);
370                         p->object.flags |= c->object.flags;
371                         parents = parents->next;
372
373                         if (first_parent)
374                                 break;
375                 }
376         }
377
378         if (!match_cnt) {
379                 struct object_id *oid = &cmit->object.oid;
380                 if (always) {
381                         printf("%s", find_unique_abbrev(oid->hash, abbrev));
382                         if (suffix)
383                                 printf("%s", suffix);
384                         printf("\n");
385                         return;
386                 }
387                 if (unannotated_cnt)
388                         die(_("No annotated tags can describe '%s'.\n"
389                             "However, there were unannotated tags: try --tags."),
390                             oid_to_hex(oid));
391                 else
392                         die(_("No tags can describe '%s'.\n"
393                             "Try --always, or create some tags."),
394                             oid_to_hex(oid));
395         }
396
397         QSORT(all_matches, match_cnt, compare_pt);
398
399         if (gave_up_on) {
400                 commit_list_insert_by_date(gave_up_on, &list);
401                 seen_commits--;
402         }
403         seen_commits += finish_depth_computation(&list, &all_matches[0]);
404         free_commit_list(list);
405
406         if (debug) {
407                 static int label_width = -1;
408                 if (label_width < 0) {
409                         int i, w;
410                         for (i = 0; i < ARRAY_SIZE(prio_names); i++) {
411                                 w = strlen(_(prio_names[i]));
412                                 if (label_width < w)
413                                         label_width = w;
414                         }
415                 }
416                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
417                         struct possible_tag *t = &all_matches[cur_match];
418                         fprintf(stderr, " %-*s %8d %s\n",
419                                 label_width, _(prio_names[t->name->prio]),
420                                 t->depth, t->name->path);
421                 }
422                 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
423                 if (gave_up_on) {
424                         fprintf(stderr,
425                                 _("more than %i tags found; listed %i most recent\n"
426                                 "gave up search at %s\n"),
427                                 max_candidates, max_candidates,
428                                 oid_to_hex(&gave_up_on->object.oid));
429                 }
430         }
431
432         display_name(all_matches[0].name);
433         if (abbrev)
434                 show_suffix(all_matches[0].depth, &cmit->object.oid);
435         if (suffix)
436                 printf("%s", suffix);
437         printf("\n");
438
439         if (!last_one)
440                 clear_commit_marks(cmit, -1);
441 }
442
443 int cmd_describe(int argc, const char **argv, const char *prefix)
444 {
445         int contains = 0;
446         struct option options[] = {
447                 OPT_BOOL(0, "contains",   &contains, N_("find the tag that comes after the commit")),
448                 OPT_BOOL(0, "debug",      &debug, N_("debug search strategy on stderr")),
449                 OPT_BOOL(0, "all",        &all, N_("use any ref")),
450                 OPT_BOOL(0, "tags",       &tags, N_("use any tag, even unannotated")),
451                 OPT_BOOL(0, "long",       &longformat, N_("always use long format")),
452                 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
453                 OPT__ABBREV(&abbrev),
454                 OPT_SET_INT(0, "exact-match", &max_candidates,
455                             N_("only output exact matches"), 0),
456                 OPT_INTEGER(0, "candidates", &max_candidates,
457                             N_("consider <n> most recent tags (default: 10)")),
458                 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
459                            N_("only consider tags matching <pattern>")),
460                 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
461                            N_("do not consider tags matching <pattern>")),
462                 OPT_BOOL(0, "always",        &always,
463                         N_("show abbreviated commit object as fallback")),
464                 {OPTION_STRING, 0, "dirty",  &dirty, N_("mark"),
465                         N_("append <mark> on dirty working tree (default: \"-dirty\")"),
466                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
467                 {OPTION_STRING, 0, "broken",  &broken, N_("mark"),
468                         N_("append <mark> on broken working tree (default: \"-broken\")"),
469                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
470                 OPT_END(),
471         };
472
473         git_config(git_default_config, NULL);
474         argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
475         if (abbrev < 0)
476                 abbrev = DEFAULT_ABBREV;
477
478         if (max_candidates < 0)
479                 max_candidates = 0;
480         else if (max_candidates > MAX_TAGS)
481                 max_candidates = MAX_TAGS;
482
483         save_commit_buffer = 0;
484
485         if (longformat && abbrev == 0)
486                 die(_("--long is incompatible with --abbrev=0"));
487
488         if (contains) {
489                 struct string_list_item *item;
490                 struct argv_array args;
491
492                 argv_array_init(&args);
493                 argv_array_pushl(&args, "name-rev",
494                                  "--peel-tag", "--name-only", "--no-undefined",
495                                  NULL);
496                 if (always)
497                         argv_array_push(&args, "--always");
498                 if (!all) {
499                         argv_array_push(&args, "--tags");
500                         for_each_string_list_item(item, &patterns)
501                                 argv_array_pushf(&args, "--refs=refs/tags/%s", item->string);
502                         for_each_string_list_item(item, &exclude_patterns)
503                                 argv_array_pushf(&args, "--exclude=refs/tags/%s", item->string);
504                 }
505                 if (argc)
506                         argv_array_pushv(&args, argv);
507                 else
508                         argv_array_push(&args, "HEAD");
509                 return cmd_name_rev(args.argc, args.argv, prefix);
510         }
511
512         hashmap_init(&names, commit_name_cmp, NULL, 0);
513         for_each_rawref(get_name, NULL);
514         if (!hashmap_get_size(&names) && !always)
515                 die(_("No names found, cannot describe anything."));
516
517         if (argc == 0) {
518                 if (broken) {
519                         struct child_process cp = CHILD_PROCESS_INIT;
520                         argv_array_pushv(&cp.args, diff_index_args);
521                         cp.git_cmd = 1;
522                         cp.no_stdin = 1;
523                         cp.no_stdout = 1;
524
525                         if (!dirty)
526                                 dirty = "-dirty";
527
528                         switch (run_command(&cp)) {
529                         case 0:
530                                 suffix = NULL;
531                                 break;
532                         case 1:
533                                 suffix = dirty;
534                                 break;
535                         default:
536                                 /* diff-index aborted abnormally */
537                                 suffix = broken;
538                         }
539                 } else if (dirty) {
540                         static struct lock_file index_lock;
541                         int fd;
542
543                         read_cache_preload(NULL);
544                         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
545                                       NULL, NULL, NULL);
546                         fd = hold_locked_index(&index_lock, 0);
547                         if (0 <= fd)
548                                 update_index_if_able(&the_index, &index_lock);
549
550                         if (!cmd_diff_index(ARRAY_SIZE(diff_index_args) - 1,
551                                             diff_index_args, prefix))
552                                 suffix = NULL;
553                         else
554                                 suffix = dirty;
555                 }
556                 describe("HEAD", 1);
557         } else if (dirty) {
558                 die(_("--dirty is incompatible with commit-ishes"));
559         } else if (broken) {
560                 die(_("--broken is incompatible with commit-ishes"));
561         } else {
562                 while (argc-- > 0)
563                         describe(*argv++, argc == 0);
564         }
565         return 0;
566 }