Merge branch 'ew/empty-merge-with-dirty-index-maint' into ew/empty-merge-with-dirty...
[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 "revision.h"
11 #include "diff.h"
12 #include "hashmap.h"
13 #include "argv-array.h"
14 #include "run-command.h"
15
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 = 0;
133         struct object_id peeled;
134         int is_annotated, prio;
135         const char *path_to_match = NULL;
136
137         if (skip_prefix(path, "refs/tags/", &path_to_match)) {
138                 is_tag = 1;
139         } else if (all) {
140                 if ((exclude_patterns.nr || patterns.nr) &&
141                     !skip_prefix(path, "refs/heads/", &path_to_match) &&
142                     !skip_prefix(path, "refs/remotes/", &path_to_match)) {
143                         /* Only accept reference of known type if there are match/exclude patterns */
144                         return 0;
145                 }
146         } else {
147                 /* Reject anything outside refs/tags/ unless --all */
148                 return 0;
149         }
150
151         /*
152          * If we're given exclude patterns, first exclude any tag which match
153          * any of the exclude pattern.
154          */
155         if (exclude_patterns.nr) {
156                 struct string_list_item *item;
157
158                 for_each_string_list_item(item, &exclude_patterns) {
159                         if (!wildmatch(item->string, path_to_match, 0))
160                                 return 0;
161                 }
162         }
163
164         /*
165          * If we're given patterns, accept only tags which match at least one
166          * pattern.
167          */
168         if (patterns.nr) {
169                 int found = 0;
170                 struct string_list_item *item;
171
172                 for_each_string_list_item(item, &patterns) {
173                         if (!wildmatch(item->string, path_to_match, 0)) {
174                                 found = 1;
175                                 break;
176                         }
177                 }
178
179                 if (!found)
180                         return 0;
181         }
182
183         /* Is it annotated? */
184         if (!peel_ref(path, &peeled)) {
185                 is_annotated = !!oidcmp(oid, &peeled);
186         } else {
187                 oidcpy(&peeled, oid);
188                 is_annotated = 0;
189         }
190
191         /*
192          * By default, we only use annotated tags, but with --tags
193          * we fall back to lightweight ones (even without --tags,
194          * we still remember lightweight ones, only to give hints
195          * in an error message).  --all allows any refs to be used.
196          */
197         if (is_annotated)
198                 prio = 2;
199         else if (is_tag)
200                 prio = 1;
201         else
202                 prio = 0;
203
204         add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
205         return 0;
206 }
207
208 struct possible_tag {
209         struct commit_name *name;
210         int depth;
211         int found_order;
212         unsigned flag_within;
213 };
214
215 static int compare_pt(const void *a_, const void *b_)
216 {
217         struct possible_tag *a = (struct possible_tag *)a_;
218         struct possible_tag *b = (struct possible_tag *)b_;
219         if (a->depth != b->depth)
220                 return a->depth - b->depth;
221         if (a->found_order != b->found_order)
222                 return a->found_order - b->found_order;
223         return 0;
224 }
225
226 static unsigned long finish_depth_computation(
227         struct commit_list **list,
228         struct possible_tag *best)
229 {
230         unsigned long seen_commits = 0;
231         while (*list) {
232                 struct commit *c = pop_commit(list);
233                 struct commit_list *parents = c->parents;
234                 seen_commits++;
235                 if (c->object.flags & best->flag_within) {
236                         struct commit_list *a = *list;
237                         while (a) {
238                                 struct commit *i = a->item;
239                                 if (!(i->object.flags & best->flag_within))
240                                         break;
241                                 a = a->next;
242                         }
243                         if (!a)
244                                 break;
245                 } else
246                         best->depth++;
247                 while (parents) {
248                         struct commit *p = parents->item;
249                         parse_commit(p);
250                         if (!(p->object.flags & SEEN))
251                                 commit_list_insert_by_date(p, list);
252                         p->object.flags |= c->object.flags;
253                         parents = parents->next;
254                 }
255         }
256         return seen_commits;
257 }
258
259 static void display_name(struct commit_name *n)
260 {
261         if (n->prio == 2 && !n->tag) {
262                 n->tag = lookup_tag(&n->oid);
263                 if (!n->tag || parse_tag(n->tag))
264                         die(_("annotated tag %s not available"), n->path);
265         }
266         if (n->tag && !n->name_checked) {
267                 if (!n->tag->tag)
268                         die(_("annotated tag %s has no embedded name"), n->path);
269                 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
270                         warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
271                 n->name_checked = 1;
272         }
273
274         if (n->tag)
275                 printf("%s", n->tag->tag);
276         else
277                 printf("%s", n->path);
278 }
279
280 static void show_suffix(int depth, const struct object_id *oid)
281 {
282         printf("-%d-g%s", depth, find_unique_abbrev(oid->hash, abbrev));
283 }
284
285 static void describe(const char *arg, int last_one)
286 {
287         struct object_id oid;
288         struct commit *cmit, *gave_up_on = NULL;
289         struct commit_list *list;
290         struct commit_name *n;
291         struct possible_tag all_matches[MAX_TAGS];
292         unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
293         unsigned long seen_commits = 0;
294         unsigned int unannotated_cnt = 0;
295
296         if (get_oid(arg, &oid))
297                 die(_("Not a valid object name %s"), arg);
298         cmit = lookup_commit_reference(&oid);
299         if (!cmit)
300                 die(_("%s is not a valid '%s' object"), arg, commit_type);
301
302         n = find_commit_name(&cmit->object.oid);
303         if (n && (tags || all || n->prio == 2)) {
304                 /*
305                  * Exact match to an existing ref.
306                  */
307                 display_name(n);
308                 if (longformat)
309                         show_suffix(0, n->tag ? &n->tag->tagged->oid : &oid);
310                 if (suffix)
311                         printf("%s", suffix);
312                 printf("\n");
313                 return;
314         }
315
316         if (!max_candidates)
317                 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
318         if (debug)
319                 fprintf(stderr, _("searching to describe %s\n"), arg);
320
321         if (!have_util) {
322                 struct hashmap_iter iter;
323                 struct commit *c;
324                 struct commit_name *n = hashmap_iter_first(&names, &iter);
325                 for (; n; n = hashmap_iter_next(&iter)) {
326                         c = lookup_commit_reference_gently(&n->peeled, 1);
327                         if (c)
328                                 c->util = n;
329                 }
330                 have_util = 1;
331         }
332
333         list = NULL;
334         cmit->object.flags = SEEN;
335         commit_list_insert(cmit, &list);
336         while (list) {
337                 struct commit *c = pop_commit(&list);
338                 struct commit_list *parents = c->parents;
339                 seen_commits++;
340                 n = c->util;
341                 if (n) {
342                         if (!tags && !all && n->prio < 2) {
343                                 unannotated_cnt++;
344                         } else if (match_cnt < max_candidates) {
345                                 struct possible_tag *t = &all_matches[match_cnt++];
346                                 t->name = n;
347                                 t->depth = seen_commits - 1;
348                                 t->flag_within = 1u << match_cnt;
349                                 t->found_order = match_cnt;
350                                 c->object.flags |= t->flag_within;
351                                 if (n->prio == 2)
352                                         annotated_cnt++;
353                         }
354                         else {
355                                 gave_up_on = c;
356                                 break;
357                         }
358                 }
359                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
360                         struct possible_tag *t = &all_matches[cur_match];
361                         if (!(c->object.flags & t->flag_within))
362                                 t->depth++;
363                 }
364                 if (annotated_cnt && !list) {
365                         if (debug)
366                                 fprintf(stderr, _("finished search at %s\n"),
367                                         oid_to_hex(&c->object.oid));
368                         break;
369                 }
370                 while (parents) {
371                         struct commit *p = parents->item;
372                         parse_commit(p);
373                         if (!(p->object.flags & SEEN))
374                                 commit_list_insert_by_date(p, &list);
375                         p->object.flags |= c->object.flags;
376                         parents = parents->next;
377
378                         if (first_parent)
379                                 break;
380                 }
381         }
382
383         if (!match_cnt) {
384                 struct object_id *oid = &cmit->object.oid;
385                 if (always) {
386                         printf("%s", find_unique_abbrev(oid->hash, abbrev));
387                         if (suffix)
388                                 printf("%s", suffix);
389                         printf("\n");
390                         return;
391                 }
392                 if (unannotated_cnt)
393                         die(_("No annotated tags can describe '%s'.\n"
394                             "However, there were unannotated tags: try --tags."),
395                             oid_to_hex(oid));
396                 else
397                         die(_("No tags can describe '%s'.\n"
398                             "Try --always, or create some tags."),
399                             oid_to_hex(oid));
400         }
401
402         QSORT(all_matches, match_cnt, compare_pt);
403
404         if (gave_up_on) {
405                 commit_list_insert_by_date(gave_up_on, &list);
406                 seen_commits--;
407         }
408         seen_commits += finish_depth_computation(&list, &all_matches[0]);
409         free_commit_list(list);
410
411         if (debug) {
412                 static int label_width = -1;
413                 if (label_width < 0) {
414                         int i, w;
415                         for (i = 0; i < ARRAY_SIZE(prio_names); i++) {
416                                 w = strlen(_(prio_names[i]));
417                                 if (label_width < w)
418                                         label_width = w;
419                         }
420                 }
421                 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
422                         struct possible_tag *t = &all_matches[cur_match];
423                         fprintf(stderr, " %-*s %8d %s\n",
424                                 label_width, _(prio_names[t->name->prio]),
425                                 t->depth, t->name->path);
426                 }
427                 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
428                 if (gave_up_on) {
429                         fprintf(stderr,
430                                 _("more than %i tags found; listed %i most recent\n"
431                                 "gave up search at %s\n"),
432                                 max_candidates, max_candidates,
433                                 oid_to_hex(&gave_up_on->object.oid));
434                 }
435         }
436
437         display_name(all_matches[0].name);
438         if (abbrev)
439                 show_suffix(all_matches[0].depth, &cmit->object.oid);
440         if (suffix)
441                 printf("%s", suffix);
442         printf("\n");
443
444         if (!last_one)
445                 clear_commit_marks(cmit, -1);
446 }
447
448 int cmd_describe(int argc, const char **argv, const char *prefix)
449 {
450         int contains = 0;
451         struct option options[] = {
452                 OPT_BOOL(0, "contains",   &contains, N_("find the tag that comes after the commit")),
453                 OPT_BOOL(0, "debug",      &debug, N_("debug search strategy on stderr")),
454                 OPT_BOOL(0, "all",        &all, N_("use any ref")),
455                 OPT_BOOL(0, "tags",       &tags, N_("use any tag, even unannotated")),
456                 OPT_BOOL(0, "long",       &longformat, N_("always use long format")),
457                 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
458                 OPT__ABBREV(&abbrev),
459                 OPT_SET_INT(0, "exact-match", &max_candidates,
460                             N_("only output exact matches"), 0),
461                 OPT_INTEGER(0, "candidates", &max_candidates,
462                             N_("consider <n> most recent tags (default: 10)")),
463                 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
464                            N_("only consider tags matching <pattern>")),
465                 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
466                            N_("do not consider tags matching <pattern>")),
467                 OPT_BOOL(0, "always",        &always,
468                         N_("show abbreviated commit object as fallback")),
469                 {OPTION_STRING, 0, "dirty",  &dirty, N_("mark"),
470                         N_("append <mark> on dirty working tree (default: \"-dirty\")"),
471                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
472                 {OPTION_STRING, 0, "broken",  &broken, N_("mark"),
473                         N_("append <mark> on broken working tree (default: \"-broken\")"),
474                         PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
475                 OPT_END(),
476         };
477
478         git_config(git_default_config, NULL);
479         argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
480         if (abbrev < 0)
481                 abbrev = DEFAULT_ABBREV;
482
483         if (max_candidates < 0)
484                 max_candidates = 0;
485         else if (max_candidates > MAX_TAGS)
486                 max_candidates = MAX_TAGS;
487
488         save_commit_buffer = 0;
489
490         if (longformat && abbrev == 0)
491                 die(_("--long is incompatible with --abbrev=0"));
492
493         if (contains) {
494                 struct string_list_item *item;
495                 struct argv_array args;
496
497                 argv_array_init(&args);
498                 argv_array_pushl(&args, "name-rev",
499                                  "--peel-tag", "--name-only", "--no-undefined",
500                                  NULL);
501                 if (always)
502                         argv_array_push(&args, "--always");
503                 if (!all) {
504                         argv_array_push(&args, "--tags");
505                         for_each_string_list_item(item, &patterns)
506                                 argv_array_pushf(&args, "--refs=refs/tags/%s", item->string);
507                         for_each_string_list_item(item, &exclude_patterns)
508                                 argv_array_pushf(&args, "--exclude=refs/tags/%s", item->string);
509                 }
510                 if (argc)
511                         argv_array_pushv(&args, argv);
512                 else
513                         argv_array_push(&args, "HEAD");
514                 return cmd_name_rev(args.argc, args.argv, prefix);
515         }
516
517         hashmap_init(&names, commit_name_cmp, NULL, 0);
518         for_each_rawref(get_name, NULL);
519         if (!hashmap_get_size(&names) && !always)
520                 die(_("No names found, cannot describe anything."));
521
522         if (argc == 0) {
523                 if (broken) {
524                         struct child_process cp = CHILD_PROCESS_INIT;
525                         argv_array_pushv(&cp.args, diff_index_args);
526                         cp.git_cmd = 1;
527                         cp.no_stdin = 1;
528                         cp.no_stdout = 1;
529
530                         if (!dirty)
531                                 dirty = "-dirty";
532
533                         switch (run_command(&cp)) {
534                         case 0:
535                                 suffix = NULL;
536                                 break;
537                         case 1:
538                                 suffix = dirty;
539                                 break;
540                         default:
541                                 /* diff-index aborted abnormally */
542                                 suffix = broken;
543                         }
544                 } else if (dirty) {
545                         static struct lock_file index_lock;
546                         struct rev_info revs;
547                         struct argv_array args = ARGV_ARRAY_INIT;
548                         int fd, result;
549
550                         read_cache_preload(NULL);
551                         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
552                                       NULL, NULL, NULL);
553                         fd = hold_locked_index(&index_lock, 0);
554                         if (0 <= fd)
555                                 update_index_if_able(&the_index, &index_lock);
556
557                         init_revisions(&revs, prefix);
558                         argv_array_pushv(&args, diff_index_args);
559                         if (setup_revisions(args.argc, args.argv, &revs, NULL) != 1)
560                                 BUG("malformed internal diff-index command line");
561                         result = run_diff_index(&revs, 0);
562
563                         if (!diff_result_code(&revs.diffopt, result))
564                                 suffix = NULL;
565                         else
566                                 suffix = dirty;
567                 }
568                 describe("HEAD", 1);
569         } else if (dirty) {
570                 die(_("--dirty is incompatible with commit-ishes"));
571         } else if (broken) {
572                 die(_("--broken is incompatible with commit-ishes"));
573         } else {
574                 while (argc-- > 0)
575                         describe(*argv++, argc == 0);
576         }
577         return 0;
578 }