Merge branch 'bw/protocol-v1'
[git/git.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 "blob.h"
7 #include "refs.h"
8 #include "builtin.h"
9 #include "exec_cmd.h"
10 #include "parse-options.h"
11 #include "revision.h"
12 #include "diff.h"
13 #include "hashmap.h"
14 #include "argv-array.h"
15 #include "run-command.h"
16 #include "revision.h"
17 #include "list-objects.h"
18
19 #define MAX_TAGS (FLAG_BITS - 1)
20
21 static const char * const describe_usage[] = {
22 N_("git describe [<options>] [<commit-ish>...]"),
23 N_("git describe [<options>] --dirty"),
24 NULL
25 };
26
27 static int debug; /* Display lots of verbose info */
28 static int all; /* Any valid ref can be used */
29 static int tags; /* Allow lightweight tags */
30 static int longformat;
31 static int first_parent;
32 static int abbrev = -1; /* unspecified */
33 static int max_candidates = 10;
34 static struct hashmap names;
35 static int have_util;
36 static struct string_list patterns = STRING_LIST_INIT_NODUP;
37 static struct string_list exclude_patterns = STRING_LIST_INIT_NODUP;
38 static int always;
39 static const char *suffix, *dirty, *broken;
40
41 /* diff-index command arguments to check if working tree is dirty. */
42 static const char *diff_index_args[] = {
43 "diff-index", "--quiet", "HEAD", "--", NULL
44 };
45
46 struct commit_name {
47 struct hashmap_entry entry;
48 struct object_id peeled;
49 struct tag *tag;
50 unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
51 unsigned name_checked:1;
52 struct object_id oid;
53 char *path;
54 };
55
56 static const char *prio_names[] = {
57 N_("head"), N_("lightweight"), N_("annotated"),
58 };
59
60 static int commit_name_cmp(const void *unused_cmp_data,
61 const void *entry,
62 const void *entry_or_key,
63 const void *peeled)
64 {
65 const struct commit_name *cn1 = entry;
66 const struct commit_name *cn2 = entry_or_key;
67
68 return oidcmp(&cn1->peeled, peeled ? peeled : &cn2->peeled);
69 }
70
71 static inline struct commit_name *find_commit_name(const struct object_id *peeled)
72 {
73 return hashmap_get_from_hash(&names, sha1hash(peeled->hash), peeled->hash);
74 }
75
76 static int replace_name(struct commit_name *e,
77 int prio,
78 const struct object_id *oid,
79 struct tag **tag)
80 {
81 if (!e || e->prio < prio)
82 return 1;
83
84 if (e->prio == 2 && prio == 2) {
85 /* Multiple annotated tags point to the same commit.
86 * Select one to keep based upon their tagger date.
87 */
88 struct tag *t;
89
90 if (!e->tag) {
91 t = lookup_tag(&e->oid);
92 if (!t || parse_tag(t))
93 return 1;
94 e->tag = t;
95 }
96
97 t = lookup_tag(oid);
98 if (!t || parse_tag(t))
99 return 0;
100 *tag = t;
101
102 if (e->tag->date < t->date)
103 return 1;
104 }
105
106 return 0;
107 }
108
109 static void add_to_known_names(const char *path,
110 const struct object_id *peeled,
111 int prio,
112 const struct object_id *oid)
113 {
114 struct commit_name *e = find_commit_name(peeled);
115 struct tag *tag = NULL;
116 if (replace_name(e, prio, oid, &tag)) {
117 if (!e) {
118 e = xmalloc(sizeof(struct commit_name));
119 oidcpy(&e->peeled, peeled);
120 hashmap_entry_init(e, sha1hash(peeled->hash));
121 hashmap_add(&names, e);
122 e->path = NULL;
123 }
124 e->tag = tag;
125 e->prio = prio;
126 e->name_checked = 0;
127 oidcpy(&e->oid, oid);
128 free(e->path);
129 e->path = xstrdup(path);
130 }
131 }
132
133 static int get_name(const char *path, const struct object_id *oid, int flag, void *cb_data)
134 {
135 int is_tag = 0;
136 struct object_id peeled;
137 int is_annotated, prio;
138 const char *path_to_match = NULL;
139
140 if (skip_prefix(path, "refs/tags/", &path_to_match)) {
141 is_tag = 1;
142 } else if (all) {
143 if ((exclude_patterns.nr || patterns.nr) &&
144 !skip_prefix(path, "refs/heads/", &path_to_match) &&
145 !skip_prefix(path, "refs/remotes/", &path_to_match)) {
146 /* Only accept reference of known type if there are match/exclude patterns */
147 return 0;
148 }
149 } else {
150 /* Reject anything outside refs/tags/ unless --all */
151 return 0;
152 }
153
154 /*
155 * If we're given exclude patterns, first exclude any tag which match
156 * any of the exclude pattern.
157 */
158 if (exclude_patterns.nr) {
159 struct string_list_item *item;
160
161 for_each_string_list_item(item, &exclude_patterns) {
162 if (!wildmatch(item->string, path_to_match, 0))
163 return 0;
164 }
165 }
166
167 /*
168 * If we're given patterns, accept only tags which match at least one
169 * pattern.
170 */
171 if (patterns.nr) {
172 int found = 0;
173 struct string_list_item *item;
174
175 for_each_string_list_item(item, &patterns) {
176 if (!wildmatch(item->string, path_to_match, 0)) {
177 found = 1;
178 break;
179 }
180 }
181
182 if (!found)
183 return 0;
184 }
185
186 /* Is it annotated? */
187 if (!peel_ref(path, &peeled)) {
188 is_annotated = !!oidcmp(oid, &peeled);
189 } else {
190 oidcpy(&peeled, oid);
191 is_annotated = 0;
192 }
193
194 /*
195 * By default, we only use annotated tags, but with --tags
196 * we fall back to lightweight ones (even without --tags,
197 * we still remember lightweight ones, only to give hints
198 * in an error message). --all allows any refs to be used.
199 */
200 if (is_annotated)
201 prio = 2;
202 else if (is_tag)
203 prio = 1;
204 else
205 prio = 0;
206
207 add_to_known_names(all ? path + 5 : path + 10, &peeled, prio, oid);
208 return 0;
209 }
210
211 struct possible_tag {
212 struct commit_name *name;
213 int depth;
214 int found_order;
215 unsigned flag_within;
216 };
217
218 static int compare_pt(const void *a_, const void *b_)
219 {
220 struct possible_tag *a = (struct possible_tag *)a_;
221 struct possible_tag *b = (struct possible_tag *)b_;
222 if (a->depth != b->depth)
223 return a->depth - b->depth;
224 if (a->found_order != b->found_order)
225 return a->found_order - b->found_order;
226 return 0;
227 }
228
229 static unsigned long finish_depth_computation(
230 struct commit_list **list,
231 struct possible_tag *best)
232 {
233 unsigned long seen_commits = 0;
234 while (*list) {
235 struct commit *c = pop_commit(list);
236 struct commit_list *parents = c->parents;
237 seen_commits++;
238 if (c->object.flags & best->flag_within) {
239 struct commit_list *a = *list;
240 while (a) {
241 struct commit *i = a->item;
242 if (!(i->object.flags & best->flag_within))
243 break;
244 a = a->next;
245 }
246 if (!a)
247 break;
248 } else
249 best->depth++;
250 while (parents) {
251 struct commit *p = parents->item;
252 parse_commit(p);
253 if (!(p->object.flags & SEEN))
254 commit_list_insert_by_date(p, list);
255 p->object.flags |= c->object.flags;
256 parents = parents->next;
257 }
258 }
259 return seen_commits;
260 }
261
262 static void append_name(struct commit_name *n, struct strbuf *dst)
263 {
264 if (n->prio == 2 && !n->tag) {
265 n->tag = lookup_tag(&n->oid);
266 if (!n->tag || parse_tag(n->tag))
267 die(_("annotated tag %s not available"), n->path);
268 }
269 if (n->tag && !n->name_checked) {
270 if (!n->tag->tag)
271 die(_("annotated tag %s has no embedded name"), n->path);
272 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
273 warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
274 n->name_checked = 1;
275 }
276
277 if (n->tag)
278 strbuf_addstr(dst, n->tag->tag);
279 else
280 strbuf_addstr(dst, n->path);
281 }
282
283 static void append_suffix(int depth, const struct object_id *oid, struct strbuf *dst)
284 {
285 strbuf_addf(dst, "-%d-g%s", depth, find_unique_abbrev(oid->hash, abbrev));
286 }
287
288 static void describe_commit(struct object_id *oid, struct strbuf *dst)
289 {
290 struct commit *cmit, *gave_up_on = NULL;
291 struct commit_list *list;
292 struct commit_name *n;
293 struct possible_tag all_matches[MAX_TAGS];
294 unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
295 unsigned long seen_commits = 0;
296 unsigned int unannotated_cnt = 0;
297
298 cmit = lookup_commit_reference(oid);
299
300 n = find_commit_name(&cmit->object.oid);
301 if (n && (tags || all || n->prio == 2)) {
302 /*
303 * Exact match to an existing ref.
304 */
305 append_name(n, dst);
306 if (longformat)
307 append_suffix(0, n->tag ? &n->tag->tagged->oid : oid, dst);
308 if (suffix)
309 strbuf_addstr(dst, suffix);
310 return;
311 }
312
313 if (!max_candidates)
314 die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
315 if (debug)
316 fprintf(stderr, _("No exact match on refs or tags, searching to describe\n"));
317
318 if (!have_util) {
319 struct hashmap_iter iter;
320 struct commit *c;
321 struct commit_name *n = hashmap_iter_first(&names, &iter);
322 for (; n; n = hashmap_iter_next(&iter)) {
323 c = lookup_commit_reference_gently(&n->peeled, 1);
324 if (c)
325 c->util = n;
326 }
327 have_util = 1;
328 }
329
330 list = NULL;
331 cmit->object.flags = SEEN;
332 commit_list_insert(cmit, &list);
333 while (list) {
334 struct commit *c = pop_commit(&list);
335 struct commit_list *parents = c->parents;
336 seen_commits++;
337 n = c->util;
338 if (n) {
339 if (!tags && !all && n->prio < 2) {
340 unannotated_cnt++;
341 } else if (match_cnt < max_candidates) {
342 struct possible_tag *t = &all_matches[match_cnt++];
343 t->name = n;
344 t->depth = seen_commits - 1;
345 t->flag_within = 1u << match_cnt;
346 t->found_order = match_cnt;
347 c->object.flags |= t->flag_within;
348 if (n->prio == 2)
349 annotated_cnt++;
350 }
351 else {
352 gave_up_on = c;
353 break;
354 }
355 }
356 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
357 struct possible_tag *t = &all_matches[cur_match];
358 if (!(c->object.flags & t->flag_within))
359 t->depth++;
360 }
361 if (annotated_cnt && !list) {
362 if (debug)
363 fprintf(stderr, _("finished search at %s\n"),
364 oid_to_hex(&c->object.oid));
365 break;
366 }
367 while (parents) {
368 struct commit *p = parents->item;
369 parse_commit(p);
370 if (!(p->object.flags & SEEN))
371 commit_list_insert_by_date(p, &list);
372 p->object.flags |= c->object.flags;
373 parents = parents->next;
374
375 if (first_parent)
376 break;
377 }
378 }
379
380 if (!match_cnt) {
381 struct object_id *cmit_oid = &cmit->object.oid;
382 if (always) {
383 strbuf_addstr(dst, find_unique_abbrev(cmit_oid->hash, abbrev));
384 if (suffix)
385 strbuf_addstr(dst, suffix);
386 return;
387 }
388 if (unannotated_cnt)
389 die(_("No annotated tags can describe '%s'.\n"
390 "However, there were unannotated tags: try --tags."),
391 oid_to_hex(cmit_oid));
392 else
393 die(_("No tags can describe '%s'.\n"
394 "Try --always, or create some tags."),
395 oid_to_hex(cmit_oid));
396 }
397
398 QSORT(all_matches, match_cnt, compare_pt);
399
400 if (gave_up_on) {
401 commit_list_insert_by_date(gave_up_on, &list);
402 seen_commits--;
403 }
404 seen_commits += finish_depth_computation(&list, &all_matches[0]);
405 free_commit_list(list);
406
407 if (debug) {
408 static int label_width = -1;
409 if (label_width < 0) {
410 int i, w;
411 for (i = 0; i < ARRAY_SIZE(prio_names); i++) {
412 w = strlen(_(prio_names[i]));
413 if (label_width < w)
414 label_width = w;
415 }
416 }
417 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
418 struct possible_tag *t = &all_matches[cur_match];
419 fprintf(stderr, " %-*s %8d %s\n",
420 label_width, _(prio_names[t->name->prio]),
421 t->depth, t->name->path);
422 }
423 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
424 if (gave_up_on) {
425 fprintf(stderr,
426 _("more than %i tags found; listed %i most recent\n"
427 "gave up search at %s\n"),
428 max_candidates, max_candidates,
429 oid_to_hex(&gave_up_on->object.oid));
430 }
431 }
432
433 append_name(all_matches[0].name, dst);
434 if (abbrev)
435 append_suffix(all_matches[0].depth, &cmit->object.oid, dst);
436 if (suffix)
437 strbuf_addstr(dst, suffix);
438 }
439
440 struct process_commit_data {
441 struct object_id current_commit;
442 struct object_id looking_for;
443 struct strbuf *dst;
444 struct rev_info *revs;
445 };
446
447 static void process_commit(struct commit *commit, void *data)
448 {
449 struct process_commit_data *pcd = data;
450 pcd->current_commit = commit->object.oid;
451 }
452
453 static void process_object(struct object *obj, const char *path, void *data)
454 {
455 struct process_commit_data *pcd = data;
456
457 if (!oidcmp(&pcd->looking_for, &obj->oid) && !pcd->dst->len) {
458 reset_revision_walk();
459 describe_commit(&pcd->current_commit, pcd->dst);
460 strbuf_addf(pcd->dst, ":%s", path);
461 free_commit_list(pcd->revs->commits);
462 pcd->revs->commits = NULL;
463 }
464 }
465
466 static void describe_blob(struct object_id oid, struct strbuf *dst)
467 {
468 struct rev_info revs;
469 struct argv_array args = ARGV_ARRAY_INIT;
470 struct process_commit_data pcd = { null_oid, oid, dst, &revs};
471
472 argv_array_pushl(&args, "internal: The first arg is not parsed",
473 "--objects", "--in-commit-order", "--reverse", "HEAD",
474 NULL);
475
476 init_revisions(&revs, NULL);
477 if (setup_revisions(args.argc, args.argv, &revs, NULL) > 1)
478 BUG("setup_revisions could not handle all args?");
479
480 if (prepare_revision_walk(&revs))
481 die("revision walk setup failed");
482
483 traverse_commit_list(&revs, process_commit, process_object, &pcd);
484 reset_revision_walk();
485 }
486
487 static void describe(const char *arg, int last_one)
488 {
489 struct object_id oid;
490 struct commit *cmit;
491 struct strbuf sb = STRBUF_INIT;
492
493 if (debug)
494 fprintf(stderr, _("describe %s\n"), arg);
495
496 if (get_oid(arg, &oid))
497 die(_("Not a valid object name %s"), arg);
498 cmit = lookup_commit_reference_gently(&oid, 1);
499
500 if (cmit)
501 describe_commit(&oid, &sb);
502 else if (lookup_blob(&oid))
503 describe_blob(oid, &sb);
504 else
505 die(_("%s is neither a commit nor blob"), arg);
506
507 puts(sb.buf);
508
509 if (!last_one)
510 clear_commit_marks(cmit, -1);
511
512 strbuf_release(&sb);
513 }
514
515 int cmd_describe(int argc, const char **argv, const char *prefix)
516 {
517 int contains = 0;
518 struct option options[] = {
519 OPT_BOOL(0, "contains", &contains, N_("find the tag that comes after the commit")),
520 OPT_BOOL(0, "debug", &debug, N_("debug search strategy on stderr")),
521 OPT_BOOL(0, "all", &all, N_("use any ref")),
522 OPT_BOOL(0, "tags", &tags, N_("use any tag, even unannotated")),
523 OPT_BOOL(0, "long", &longformat, N_("always use long format")),
524 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
525 OPT__ABBREV(&abbrev),
526 OPT_SET_INT(0, "exact-match", &max_candidates,
527 N_("only output exact matches"), 0),
528 OPT_INTEGER(0, "candidates", &max_candidates,
529 N_("consider <n> most recent tags (default: 10)")),
530 OPT_STRING_LIST(0, "match", &patterns, N_("pattern"),
531 N_("only consider tags matching <pattern>")),
532 OPT_STRING_LIST(0, "exclude", &exclude_patterns, N_("pattern"),
533 N_("do not consider tags matching <pattern>")),
534 OPT_BOOL(0, "always", &always,
535 N_("show abbreviated commit object as fallback")),
536 {OPTION_STRING, 0, "dirty", &dirty, N_("mark"),
537 N_("append <mark> on dirty working tree (default: \"-dirty\")"),
538 PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
539 {OPTION_STRING, 0, "broken", &broken, N_("mark"),
540 N_("append <mark> on broken working tree (default: \"-broken\")"),
541 PARSE_OPT_OPTARG, NULL, (intptr_t) "-broken"},
542 OPT_END(),
543 };
544
545 git_config(git_default_config, NULL);
546 argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
547 if (abbrev < 0)
548 abbrev = DEFAULT_ABBREV;
549
550 if (max_candidates < 0)
551 max_candidates = 0;
552 else if (max_candidates > MAX_TAGS)
553 max_candidates = MAX_TAGS;
554
555 save_commit_buffer = 0;
556
557 if (longformat && abbrev == 0)
558 die(_("--long is incompatible with --abbrev=0"));
559
560 if (contains) {
561 struct string_list_item *item;
562 struct argv_array args;
563
564 argv_array_init(&args);
565 argv_array_pushl(&args, "name-rev",
566 "--peel-tag", "--name-only", "--no-undefined",
567 NULL);
568 if (always)
569 argv_array_push(&args, "--always");
570 if (!all) {
571 argv_array_push(&args, "--tags");
572 for_each_string_list_item(item, &patterns)
573 argv_array_pushf(&args, "--refs=refs/tags/%s", item->string);
574 for_each_string_list_item(item, &exclude_patterns)
575 argv_array_pushf(&args, "--exclude=refs/tags/%s", item->string);
576 }
577 if (argc)
578 argv_array_pushv(&args, argv);
579 else
580 argv_array_push(&args, "HEAD");
581 return cmd_name_rev(args.argc, args.argv, prefix);
582 }
583
584 hashmap_init(&names, commit_name_cmp, NULL, 0);
585 for_each_rawref(get_name, NULL);
586 if (!hashmap_get_size(&names) && !always)
587 die(_("No names found, cannot describe anything."));
588
589 if (argc == 0) {
590 if (broken) {
591 struct child_process cp = CHILD_PROCESS_INIT;
592 argv_array_pushv(&cp.args, diff_index_args);
593 cp.git_cmd = 1;
594 cp.no_stdin = 1;
595 cp.no_stdout = 1;
596
597 if (!dirty)
598 dirty = "-dirty";
599
600 switch (run_command(&cp)) {
601 case 0:
602 suffix = NULL;
603 break;
604 case 1:
605 suffix = dirty;
606 break;
607 default:
608 /* diff-index aborted abnormally */
609 suffix = broken;
610 }
611 } else if (dirty) {
612 static struct lock_file index_lock;
613 struct rev_info revs;
614 struct argv_array args = ARGV_ARRAY_INIT;
615 int fd, result;
616
617 read_cache_preload(NULL);
618 refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
619 NULL, NULL, NULL);
620 fd = hold_locked_index(&index_lock, 0);
621 if (0 <= fd)
622 update_index_if_able(&the_index, &index_lock);
623
624 init_revisions(&revs, prefix);
625 argv_array_pushv(&args, diff_index_args);
626 if (setup_revisions(args.argc, args.argv, &revs, NULL) != 1)
627 BUG("malformed internal diff-index command line");
628 result = run_diff_index(&revs, 0);
629
630 if (!diff_result_code(&revs.diffopt, result))
631 suffix = NULL;
632 else
633 suffix = dirty;
634 }
635 describe("HEAD", 1);
636 } else if (dirty) {
637 die(_("--dirty is incompatible with commit-ishes"));
638 } else if (broken) {
639 die(_("--broken is incompatible with commit-ishes"));
640 } else {
641 while (argc-- > 0)
642 describe(*argv++, argc == 0);
643 }
644 return 0;
645 }