lockfile.h: extract new header file for the functions in lockfile.c
[git/git.git] / builtin / describe.c
1 #include "cache.h"
2 #include "lockfile.h"
3 #include "commit.h"
4 #include "tag.h"
5 #include "refs.h"
6 #include "builtin.h"
7 #include "exec_cmd.h"
8 #include "parse-options.h"
9 #include "diff.h"
10 #include "hashmap.h"
11 #include "argv-array.h"
12
13 #define SEEN (1u << 0)
14 #define MAX_TAGS (FLAG_BITS - 1)
15
16 static const char * const describe_usage[] = {
17 N_("git describe [options] <commit-ish>*"),
18 N_("git describe [options] --dirty"),
19 NULL
20 };
21
22 static int debug; /* Display lots of verbose info */
23 static int all; /* Any valid ref can be used */
24 static int tags; /* Allow lightweight tags */
25 static int longformat;
26 static int first_parent;
27 static int abbrev = -1; /* unspecified */
28 static int max_candidates = 10;
29 static struct hashmap names;
30 static int have_util;
31 static const char *pattern;
32 static int always;
33 static const char *dirty;
34
35 /* diff-index command arguments to check if working tree is dirty. */
36 static const char *diff_index_args[] = {
37 "diff-index", "--quiet", "HEAD", "--", NULL
38 };
39
40 struct commit_name {
41 struct hashmap_entry entry;
42 unsigned char peeled[20];
43 struct tag *tag;
44 unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
45 unsigned name_checked:1;
46 unsigned char sha1[20];
47 char *path;
48 };
49
50 static const char *prio_names[] = {
51 "head", "lightweight", "annotated",
52 };
53
54 static int commit_name_cmp(const struct commit_name *cn1,
55 const struct commit_name *cn2, const void *peeled)
56 {
57 return hashcmp(cn1->peeled, peeled ? peeled : cn2->peeled);
58 }
59
60 static inline struct commit_name *find_commit_name(const unsigned char *peeled)
61 {
62 return hashmap_get_from_hash(&names, sha1hash(peeled), peeled);
63 }
64
65 static int replace_name(struct commit_name *e,
66 int prio,
67 const unsigned char *sha1,
68 struct tag **tag)
69 {
70 if (!e || e->prio < prio)
71 return 1;
72
73 if (e->prio == 2 && prio == 2) {
74 /* Multiple annotated tags point to the same commit.
75 * Select one to keep based upon their tagger date.
76 */
77 struct tag *t;
78
79 if (!e->tag) {
80 t = lookup_tag(e->sha1);
81 if (!t || parse_tag(t))
82 return 1;
83 e->tag = t;
84 }
85
86 t = lookup_tag(sha1);
87 if (!t || parse_tag(t))
88 return 0;
89 *tag = t;
90
91 if (e->tag->date < t->date)
92 return 1;
93 }
94
95 return 0;
96 }
97
98 static void add_to_known_names(const char *path,
99 const unsigned char *peeled,
100 int prio,
101 const unsigned char *sha1)
102 {
103 struct commit_name *e = find_commit_name(peeled);
104 struct tag *tag = NULL;
105 if (replace_name(e, prio, sha1, &tag)) {
106 if (!e) {
107 e = xmalloc(sizeof(struct commit_name));
108 hashcpy(e->peeled, peeled);
109 hashmap_entry_init(e, sha1hash(peeled));
110 hashmap_add(&names, e);
111 e->path = NULL;
112 }
113 e->tag = tag;
114 e->prio = prio;
115 e->name_checked = 0;
116 hashcpy(e->sha1, sha1);
117 free(e->path);
118 e->path = xstrdup(path);
119 }
120 }
121
122 static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
123 {
124 int is_tag = starts_with(path, "refs/tags/");
125 unsigned char peeled[20];
126 int is_annotated, prio;
127
128 /* Reject anything outside refs/tags/ unless --all */
129 if (!all && !is_tag)
130 return 0;
131
132 /* Accept only tags that match the pattern, if given */
133 if (pattern && (!is_tag || wildmatch(pattern, path + 10, 0, NULL)))
134 return 0;
135
136 /* Is it annotated? */
137 if (!peel_ref(path, peeled)) {
138 is_annotated = !!hashcmp(sha1, peeled);
139 } else {
140 hashcpy(peeled, sha1);
141 is_annotated = 0;
142 }
143
144 /*
145 * By default, we only use annotated tags, but with --tags
146 * we fall back to lightweight ones (even without --tags,
147 * we still remember lightweight ones, only to give hints
148 * in an error message). --all allows any refs to be used.
149 */
150 if (is_annotated)
151 prio = 2;
152 else if (is_tag)
153 prio = 1;
154 else
155 prio = 0;
156
157 add_to_known_names(all ? path + 5 : path + 10, peeled, prio, sha1);
158 return 0;
159 }
160
161 struct possible_tag {
162 struct commit_name *name;
163 int depth;
164 int found_order;
165 unsigned flag_within;
166 };
167
168 static int compare_pt(const void *a_, const void *b_)
169 {
170 struct possible_tag *a = (struct possible_tag *)a_;
171 struct possible_tag *b = (struct possible_tag *)b_;
172 if (a->depth != b->depth)
173 return a->depth - b->depth;
174 if (a->found_order != b->found_order)
175 return a->found_order - b->found_order;
176 return 0;
177 }
178
179 static unsigned long finish_depth_computation(
180 struct commit_list **list,
181 struct possible_tag *best)
182 {
183 unsigned long seen_commits = 0;
184 while (*list) {
185 struct commit *c = pop_commit(list);
186 struct commit_list *parents = c->parents;
187 seen_commits++;
188 if (c->object.flags & best->flag_within) {
189 struct commit_list *a = *list;
190 while (a) {
191 struct commit *i = a->item;
192 if (!(i->object.flags & best->flag_within))
193 break;
194 a = a->next;
195 }
196 if (!a)
197 break;
198 } else
199 best->depth++;
200 while (parents) {
201 struct commit *p = parents->item;
202 parse_commit(p);
203 if (!(p->object.flags & SEEN))
204 commit_list_insert_by_date(p, list);
205 p->object.flags |= c->object.flags;
206 parents = parents->next;
207 }
208 }
209 return seen_commits;
210 }
211
212 static void display_name(struct commit_name *n)
213 {
214 if (n->prio == 2 && !n->tag) {
215 n->tag = lookup_tag(n->sha1);
216 if (!n->tag || parse_tag(n->tag))
217 die(_("annotated tag %s not available"), n->path);
218 }
219 if (n->tag && !n->name_checked) {
220 if (!n->tag->tag)
221 die(_("annotated tag %s has no embedded name"), n->path);
222 if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
223 warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
224 n->name_checked = 1;
225 }
226
227 if (n->tag)
228 printf("%s", n->tag->tag);
229 else
230 printf("%s", n->path);
231 }
232
233 static void show_suffix(int depth, const unsigned char *sha1)
234 {
235 printf("-%d-g%s", depth, find_unique_abbrev(sha1, abbrev));
236 }
237
238 static void describe(const char *arg, int last_one)
239 {
240 unsigned char sha1[20];
241 struct commit *cmit, *gave_up_on = NULL;
242 struct commit_list *list;
243 struct commit_name *n;
244 struct possible_tag all_matches[MAX_TAGS];
245 unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
246 unsigned long seen_commits = 0;
247 unsigned int unannotated_cnt = 0;
248
249 if (get_sha1(arg, sha1))
250 die(_("Not a valid object name %s"), arg);
251 cmit = lookup_commit_reference(sha1);
252 if (!cmit)
253 die(_("%s is not a valid '%s' object"), arg, commit_type);
254
255 n = find_commit_name(cmit->object.sha1);
256 if (n && (tags || all || n->prio == 2)) {
257 /*
258 * Exact match to an existing ref.
259 */
260 display_name(n);
261 if (longformat)
262 show_suffix(0, n->tag ? n->tag->tagged->sha1 : sha1);
263 if (dirty)
264 printf("%s", dirty);
265 printf("\n");
266 return;
267 }
268
269 if (!max_candidates)
270 die(_("no tag exactly matches '%s'"), sha1_to_hex(cmit->object.sha1));
271 if (debug)
272 fprintf(stderr, _("searching to describe %s\n"), arg);
273
274 if (!have_util) {
275 struct hashmap_iter iter;
276 struct commit *c;
277 struct commit_name *n = hashmap_iter_first(&names, &iter);
278 for (; n; n = hashmap_iter_next(&iter)) {
279 c = lookup_commit_reference_gently(n->peeled, 1);
280 if (c)
281 c->util = n;
282 }
283 have_util = 1;
284 }
285
286 list = NULL;
287 cmit->object.flags = SEEN;
288 commit_list_insert(cmit, &list);
289 while (list) {
290 struct commit *c = pop_commit(&list);
291 struct commit_list *parents = c->parents;
292 seen_commits++;
293 n = c->util;
294 if (n) {
295 if (!tags && !all && n->prio < 2) {
296 unannotated_cnt++;
297 } else if (match_cnt < max_candidates) {
298 struct possible_tag *t = &all_matches[match_cnt++];
299 t->name = n;
300 t->depth = seen_commits - 1;
301 t->flag_within = 1u << match_cnt;
302 t->found_order = match_cnt;
303 c->object.flags |= t->flag_within;
304 if (n->prio == 2)
305 annotated_cnt++;
306 }
307 else {
308 gave_up_on = c;
309 break;
310 }
311 }
312 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
313 struct possible_tag *t = &all_matches[cur_match];
314 if (!(c->object.flags & t->flag_within))
315 t->depth++;
316 }
317 if (annotated_cnt && !list) {
318 if (debug)
319 fprintf(stderr, _("finished search at %s\n"),
320 sha1_to_hex(c->object.sha1));
321 break;
322 }
323 while (parents) {
324 struct commit *p = parents->item;
325 parse_commit(p);
326 if (!(p->object.flags & SEEN))
327 commit_list_insert_by_date(p, &list);
328 p->object.flags |= c->object.flags;
329 parents = parents->next;
330
331 if (first_parent)
332 break;
333 }
334 }
335
336 if (!match_cnt) {
337 const unsigned char *sha1 = cmit->object.sha1;
338 if (always) {
339 printf("%s", find_unique_abbrev(sha1, abbrev));
340 if (dirty)
341 printf("%s", dirty);
342 printf("\n");
343 return;
344 }
345 if (unannotated_cnt)
346 die(_("No annotated tags can describe '%s'.\n"
347 "However, there were unannotated tags: try --tags."),
348 sha1_to_hex(sha1));
349 else
350 die(_("No tags can describe '%s'.\n"
351 "Try --always, or create some tags."),
352 sha1_to_hex(sha1));
353 }
354
355 qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
356
357 if (gave_up_on) {
358 commit_list_insert_by_date(gave_up_on, &list);
359 seen_commits--;
360 }
361 seen_commits += finish_depth_computation(&list, &all_matches[0]);
362 free_commit_list(list);
363
364 if (debug) {
365 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
366 struct possible_tag *t = &all_matches[cur_match];
367 fprintf(stderr, " %-11s %8d %s\n",
368 prio_names[t->name->prio],
369 t->depth, t->name->path);
370 }
371 fprintf(stderr, _("traversed %lu commits\n"), seen_commits);
372 if (gave_up_on) {
373 fprintf(stderr,
374 _("more than %i tags found; listed %i most recent\n"
375 "gave up search at %s\n"),
376 max_candidates, max_candidates,
377 sha1_to_hex(gave_up_on->object.sha1));
378 }
379 }
380
381 display_name(all_matches[0].name);
382 if (abbrev)
383 show_suffix(all_matches[0].depth, cmit->object.sha1);
384 if (dirty)
385 printf("%s", dirty);
386 printf("\n");
387
388 if (!last_one)
389 clear_commit_marks(cmit, -1);
390 }
391
392 int cmd_describe(int argc, const char **argv, const char *prefix)
393 {
394 int contains = 0;
395 struct option options[] = {
396 OPT_BOOL(0, "contains", &contains, N_("find the tag that comes after the commit")),
397 OPT_BOOL(0, "debug", &debug, N_("debug search strategy on stderr")),
398 OPT_BOOL(0, "all", &all, N_("use any ref")),
399 OPT_BOOL(0, "tags", &tags, N_("use any tag, even unannotated")),
400 OPT_BOOL(0, "long", &longformat, N_("always use long format")),
401 OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
402 OPT__ABBREV(&abbrev),
403 OPT_SET_INT(0, "exact-match", &max_candidates,
404 N_("only output exact matches"), 0),
405 OPT_INTEGER(0, "candidates", &max_candidates,
406 N_("consider <n> most recent tags (default: 10)")),
407 OPT_STRING(0, "match", &pattern, N_("pattern"),
408 N_("only consider tags matching <pattern>")),
409 OPT_BOOL(0, "always", &always,
410 N_("show abbreviated commit object as fallback")),
411 {OPTION_STRING, 0, "dirty", &dirty, N_("mark"),
412 N_("append <mark> on dirty working tree (default: \"-dirty\")"),
413 PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
414 OPT_END(),
415 };
416
417 git_config(git_default_config, NULL);
418 argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
419 if (abbrev < 0)
420 abbrev = DEFAULT_ABBREV;
421
422 if (max_candidates < 0)
423 max_candidates = 0;
424 else if (max_candidates > MAX_TAGS)
425 max_candidates = MAX_TAGS;
426
427 save_commit_buffer = 0;
428
429 if (longformat && abbrev == 0)
430 die(_("--long is incompatible with --abbrev=0"));
431
432 if (contains) {
433 struct argv_array args;
434
435 argv_array_init(&args);
436 argv_array_pushl(&args, "name-rev",
437 "--peel-tag", "--name-only", "--no-undefined",
438 NULL);
439 if (always)
440 argv_array_push(&args, "--always");
441 if (!all) {
442 argv_array_push(&args, "--tags");
443 if (pattern)
444 argv_array_pushf(&args, "--refs=refs/tags/%s", pattern);
445 }
446 while (*argv) {
447 argv_array_push(&args, *argv);
448 argv++;
449 }
450 return cmd_name_rev(args.argc, args.argv, prefix);
451 }
452
453 hashmap_init(&names, (hashmap_cmp_fn) commit_name_cmp, 0);
454 for_each_rawref(get_name, NULL);
455 if (!names.size && !always)
456 die(_("No names found, cannot describe anything."));
457
458 if (argc == 0) {
459 if (dirty) {
460 static struct lock_file index_lock;
461 int fd;
462
463 read_cache_preload(NULL);
464 refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
465 NULL, NULL, NULL);
466 fd = hold_locked_index(&index_lock, 0);
467 if (0 <= fd)
468 update_index_if_able(&the_index, &index_lock);
469
470 if (!cmd_diff_index(ARRAY_SIZE(diff_index_args) - 1,
471 diff_index_args, prefix))
472 dirty = NULL;
473 }
474 describe("HEAD", 1);
475 } else if (dirty) {
476 die(_("--dirty is incompatible with commit-ishes"));
477 } else {
478 while (argc-- > 0)
479 describe(*argv++, argc == 0);
480 }
481 return 0;
482 }