gitweb: use new Git::Repo API, and add optional caching
[git/gitweb-caching.git] / builtin-describe.c
blobec404c839b6542deb4e15ca342fd3c0afbbedd2e
1 #include "cache.h"
2 #include "commit.h"
3 #include "tag.h"
4 #include "refs.h"
5 #include "builtin.h"
6 #include "exec_cmd.h"
7 #include "parse-options.h"
9 #define SEEN (1u<<0)
10 #define MAX_TAGS (FLAG_BITS - 1)
12 static const char * const describe_usage[] = {
13 "git describe [options] <committish>*",
14 NULL
17 static int debug; /* Display lots of verbose info */
18 static int all; /* Default to annotated tags only */
19 static int tags; /* But allow any tags if --tags is specified */
20 static int longformat;
21 static int abbrev = DEFAULT_ABBREV;
22 static int max_candidates = 10;
23 static const char *pattern;
24 static int always;
26 struct commit_name {
27 struct tag *tag;
28 int prio; /* annotated tag = 2, tag = 1, head = 0 */
29 unsigned char sha1[20];
30 char path[FLEX_ARRAY]; /* more */
32 static const char *prio_names[] = {
33 "head", "lightweight", "annotated",
36 static void add_to_known_names(const char *path,
37 struct commit *commit,
38 int prio,
39 const unsigned char *sha1)
41 struct commit_name *e = commit->util;
42 if (!e || e->prio < prio) {
43 size_t len = strlen(path)+1;
44 free(e);
45 e = xmalloc(sizeof(struct commit_name) + len);
46 e->tag = NULL;
47 e->prio = prio;
48 hashcpy(e->sha1, sha1);
49 memcpy(e->path, path, len);
50 commit->util = e;
54 static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
56 int might_be_tag = !prefixcmp(path, "refs/tags/");
57 struct commit *commit;
58 struct object *object;
59 unsigned char peeled[20];
60 int is_tag, prio;
62 if (!all && !might_be_tag)
63 return 0;
65 if (!peel_ref(path, peeled) && !is_null_sha1(peeled)) {
66 commit = lookup_commit_reference_gently(peeled, 1);
67 if (!commit)
68 return 0;
69 is_tag = !!hashcmp(sha1, commit->object.sha1);
70 } else {
71 commit = lookup_commit_reference_gently(sha1, 1);
72 object = parse_object(sha1);
73 if (!commit || !object)
74 return 0;
75 is_tag = object->type == OBJ_TAG;
78 /* If --all, then any refs are used.
79 * If --tags, then any tags are used.
80 * Otherwise only annotated tags are used.
82 if (might_be_tag) {
83 if (is_tag)
84 prio = 2;
85 else
86 prio = 1;
88 if (pattern && fnmatch(pattern, path + 10, 0))
89 prio = 0;
91 else
92 prio = 0;
94 if (!all) {
95 if (!prio)
96 return 0;
97 if (!tags && prio < 2)
98 return 0;
100 add_to_known_names(all ? path + 5 : path + 10, commit, prio, sha1);
101 return 0;
104 struct possible_tag {
105 struct commit_name *name;
106 int depth;
107 int found_order;
108 unsigned flag_within;
111 static int compare_pt(const void *a_, const void *b_)
113 struct possible_tag *a = (struct possible_tag *)a_;
114 struct possible_tag *b = (struct possible_tag *)b_;
115 if (a->name->prio != b->name->prio)
116 return b->name->prio - a->name->prio;
117 if (a->depth != b->depth)
118 return a->depth - b->depth;
119 if (a->found_order != b->found_order)
120 return a->found_order - b->found_order;
121 return 0;
124 static unsigned long finish_depth_computation(
125 struct commit_list **list,
126 struct possible_tag *best)
128 unsigned long seen_commits = 0;
129 while (*list) {
130 struct commit *c = pop_commit(list);
131 struct commit_list *parents = c->parents;
132 seen_commits++;
133 if (c->object.flags & best->flag_within) {
134 struct commit_list *a = *list;
135 while (a) {
136 struct commit *i = a->item;
137 if (!(i->object.flags & best->flag_within))
138 break;
139 a = a->next;
141 if (!a)
142 break;
143 } else
144 best->depth++;
145 while (parents) {
146 struct commit *p = parents->item;
147 parse_commit(p);
148 if (!(p->object.flags & SEEN))
149 insert_by_date(p, list);
150 p->object.flags |= c->object.flags;
151 parents = parents->next;
154 return seen_commits;
157 static void display_name(struct commit_name *n)
159 if (n->prio == 2 && !n->tag) {
160 n->tag = lookup_tag(n->sha1);
161 if (!n->tag || parse_tag(n->tag) || !n->tag->tag)
162 die("annotated tag %s not available", n->path);
163 if (strcmp(n->tag->tag, n->path))
164 warning("tag '%s' is really '%s' here", n->tag->tag, n->path);
167 if (n->tag)
168 printf("%s", n->tag->tag);
169 else
170 printf("%s", n->path);
173 static void show_suffix(int depth, const unsigned char *sha1)
175 printf("-%d-g%s", depth, find_unique_abbrev(sha1, abbrev));
178 static void describe(const char *arg, int last_one)
180 unsigned char sha1[20];
181 struct commit *cmit, *gave_up_on = NULL;
182 struct commit_list *list;
183 static int initialized = 0;
184 struct commit_name *n;
185 struct possible_tag all_matches[MAX_TAGS];
186 unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
187 unsigned long seen_commits = 0;
189 if (get_sha1(arg, sha1))
190 die("Not a valid object name %s", arg);
191 cmit = lookup_commit_reference(sha1);
192 if (!cmit)
193 die("%s is not a valid '%s' object", arg, commit_type);
195 if (!initialized) {
196 initialized = 1;
197 for_each_ref(get_name, NULL);
200 n = cmit->util;
201 if (n) {
203 * Exact match to an existing ref.
205 display_name(n);
206 if (longformat)
207 show_suffix(0, n->tag ? n->tag->tagged->sha1 : sha1);
208 printf("\n");
209 return;
212 if (!max_candidates)
213 die("no tag exactly matches '%s'", sha1_to_hex(cmit->object.sha1));
214 if (debug)
215 fprintf(stderr, "searching to describe %s\n", arg);
217 list = NULL;
218 cmit->object.flags = SEEN;
219 commit_list_insert(cmit, &list);
220 while (list) {
221 struct commit *c = pop_commit(&list);
222 struct commit_list *parents = c->parents;
223 seen_commits++;
224 n = c->util;
225 if (n) {
226 if (match_cnt < max_candidates) {
227 struct possible_tag *t = &all_matches[match_cnt++];
228 t->name = n;
229 t->depth = seen_commits - 1;
230 t->flag_within = 1u << match_cnt;
231 t->found_order = match_cnt;
232 c->object.flags |= t->flag_within;
233 if (n->prio == 2)
234 annotated_cnt++;
236 else {
237 gave_up_on = c;
238 break;
241 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
242 struct possible_tag *t = &all_matches[cur_match];
243 if (!(c->object.flags & t->flag_within))
244 t->depth++;
246 if (annotated_cnt && !list) {
247 if (debug)
248 fprintf(stderr, "finished search at %s\n",
249 sha1_to_hex(c->object.sha1));
250 break;
252 while (parents) {
253 struct commit *p = parents->item;
254 parse_commit(p);
255 if (!(p->object.flags & SEEN))
256 insert_by_date(p, &list);
257 p->object.flags |= c->object.flags;
258 parents = parents->next;
262 if (!match_cnt) {
263 const unsigned char *sha1 = cmit->object.sha1;
264 if (always) {
265 printf("%s\n", find_unique_abbrev(sha1, abbrev));
266 return;
268 die("cannot describe '%s'", sha1_to_hex(sha1));
271 qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
273 if (gave_up_on) {
274 insert_by_date(gave_up_on, &list);
275 seen_commits--;
277 seen_commits += finish_depth_computation(&list, &all_matches[0]);
278 free_commit_list(list);
280 if (debug) {
281 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
282 struct possible_tag *t = &all_matches[cur_match];
283 fprintf(stderr, " %-11s %8d %s\n",
284 prio_names[t->name->prio],
285 t->depth, t->name->path);
287 fprintf(stderr, "traversed %lu commits\n", seen_commits);
288 if (gave_up_on) {
289 fprintf(stderr,
290 "more than %i tags found; listed %i most recent\n"
291 "gave up search at %s\n",
292 max_candidates, max_candidates,
293 sha1_to_hex(gave_up_on->object.sha1));
297 display_name(all_matches[0].name);
298 if (abbrev)
299 show_suffix(all_matches[0].depth, cmit->object.sha1);
300 printf("\n");
302 if (!last_one)
303 clear_commit_marks(cmit, -1);
306 int cmd_describe(int argc, const char **argv, const char *prefix)
308 int contains = 0;
309 struct option options[] = {
310 OPT_BOOLEAN(0, "contains", &contains, "find the tag that comes after the commit"),
311 OPT_BOOLEAN(0, "debug", &debug, "debug search strategy on stderr"),
312 OPT_BOOLEAN(0, "all", &all, "use any ref in .git/refs"),
313 OPT_BOOLEAN(0, "tags", &tags, "use any tag in .git/refs/tags"),
314 OPT_BOOLEAN(0, "long", &longformat, "always use long format"),
315 OPT__ABBREV(&abbrev),
316 OPT_SET_INT(0, "exact-match", &max_candidates,
317 "only output exact matches", 0),
318 OPT_INTEGER(0, "candidates", &max_candidates,
319 "consider <n> most recent tags (default: 10)"),
320 OPT_STRING(0, "match", &pattern, "pattern",
321 "only consider tags matching <pattern>"),
322 OPT_BOOLEAN(0, "always", &always,
323 "show abbreviated commit object as fallback"),
324 OPT_END(),
327 argc = parse_options(argc, argv, options, describe_usage, 0);
328 if (max_candidates < 0)
329 max_candidates = 0;
330 else if (max_candidates > MAX_TAGS)
331 max_candidates = MAX_TAGS;
333 save_commit_buffer = 0;
335 if (longformat && abbrev == 0)
336 die("--long is incompatible with --abbrev=0");
338 if (contains) {
339 const char **args = xmalloc((7 + argc) * sizeof(char*));
340 int i = 0;
341 args[i++] = "name-rev";
342 args[i++] = "--name-only";
343 args[i++] = "--no-undefined";
344 if (always)
345 args[i++] = "--always";
346 if (!all) {
347 args[i++] = "--tags";
348 if (pattern) {
349 char *s = xmalloc(strlen("--refs=refs/tags/") + strlen(pattern) + 1);
350 sprintf(s, "--refs=refs/tags/%s", pattern);
351 args[i++] = s;
354 memcpy(args + i, argv, argc * sizeof(char*));
355 args[i + argc] = NULL;
356 return cmd_name_rev(i + argc, args, prefix);
359 if (argc == 0) {
360 describe("HEAD", 1);
361 } else {
362 while (argc-- > 0) {
363 describe(*argv++, argc == 0);
366 return 0;