git-send-email: Add --thread option
[git/aroben.git] / builtin-describe.c
blob669110cb0645629ca5b152d8328aa91d63be1550
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"
8 #define SEEN (1u<<0)
9 #define MAX_TAGS (FLAG_BITS - 1)
11 static const char describe_usage[] =
12 "git-describe [--all] [--tags] [--abbrev=<n>] <committish>*";
14 static int debug; /* Display lots of verbose info */
15 static int all; /* Default to annotated tags only */
16 static int tags; /* But allow any tags if --tags is specified */
17 static int abbrev = DEFAULT_ABBREV;
18 static int max_candidates = 10;
20 struct commit_name {
21 int prio; /* annotated tag = 2, tag = 1, head = 0 */
22 char path[FLEX_ARRAY]; /* more */
24 static const char *prio_names[] = {
25 "head", "lightweight", "annotated",
28 static void add_to_known_names(const char *path,
29 struct commit *commit,
30 int prio)
32 struct commit_name *e = commit->util;
33 if (!e || e->prio < prio) {
34 size_t len = strlen(path)+1;
35 free(e);
36 e = xmalloc(sizeof(struct commit_name) + len);
37 e->prio = prio;
38 memcpy(e->path, path, len);
39 commit->util = e;
43 static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
45 struct commit *commit = lookup_commit_reference_gently(sha1, 1);
46 struct object *object;
47 int prio;
49 if (!commit)
50 return 0;
51 object = parse_object(sha1);
52 /* If --all, then any refs are used.
53 * If --tags, then any tags are used.
54 * Otherwise only annotated tags are used.
56 if (!prefixcmp(path, "refs/tags/")) {
57 if (object->type == OBJ_TAG)
58 prio = 2;
59 else
60 prio = 1;
62 else
63 prio = 0;
65 if (!all) {
66 if (!prio)
67 return 0;
68 if (!tags && prio < 2)
69 return 0;
71 add_to_known_names(all ? path + 5 : path + 10, commit, prio);
72 return 0;
75 struct possible_tag {
76 struct commit_name *name;
77 int depth;
78 int found_order;
79 unsigned flag_within;
82 static int compare_pt(const void *a_, const void *b_)
84 struct possible_tag *a = (struct possible_tag *)a_;
85 struct possible_tag *b = (struct possible_tag *)b_;
86 if (a->name->prio != b->name->prio)
87 return b->name->prio - a->name->prio;
88 if (a->depth != b->depth)
89 return a->depth - b->depth;
90 if (a->found_order != b->found_order)
91 return a->found_order - b->found_order;
92 return 0;
95 static unsigned long finish_depth_computation(
96 struct commit_list **list,
97 struct possible_tag *best)
99 unsigned long seen_commits = 0;
100 while (*list) {
101 struct commit *c = pop_commit(list);
102 struct commit_list *parents = c->parents;
103 seen_commits++;
104 if (c->object.flags & best->flag_within) {
105 struct commit_list *a = *list;
106 while (a) {
107 struct commit *i = a->item;
108 if (!(i->object.flags & best->flag_within))
109 break;
110 a = a->next;
112 if (!a)
113 break;
114 } else
115 best->depth++;
116 while (parents) {
117 struct commit *p = parents->item;
118 parse_commit(p);
119 if (!(p->object.flags & SEEN))
120 insert_by_date(p, list);
121 p->object.flags |= c->object.flags;
122 parents = parents->next;
125 return seen_commits;
128 static void describe(const char *arg, int last_one)
130 unsigned char sha1[20];
131 struct commit *cmit, *gave_up_on = NULL;
132 struct commit_list *list;
133 static int initialized = 0;
134 struct commit_name *n;
135 struct possible_tag all_matches[MAX_TAGS];
136 unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
137 unsigned long seen_commits = 0;
139 if (get_sha1(arg, sha1))
140 die("Not a valid object name %s", arg);
141 cmit = lookup_commit_reference(sha1);
142 if (!cmit)
143 die("%s is not a valid '%s' object", arg, commit_type);
145 if (!initialized) {
146 initialized = 1;
147 for_each_ref(get_name, NULL);
150 n = cmit->util;
151 if (n) {
152 printf("%s\n", n->path);
153 return;
156 if (debug)
157 fprintf(stderr, "searching to describe %s\n", arg);
159 list = NULL;
160 cmit->object.flags = SEEN;
161 commit_list_insert(cmit, &list);
162 while (list) {
163 struct commit *c = pop_commit(&list);
164 struct commit_list *parents = c->parents;
165 seen_commits++;
166 n = c->util;
167 if (n) {
168 if (match_cnt < max_candidates) {
169 struct possible_tag *t = &all_matches[match_cnt++];
170 t->name = n;
171 t->depth = seen_commits - 1;
172 t->flag_within = 1u << match_cnt;
173 t->found_order = match_cnt;
174 c->object.flags |= t->flag_within;
175 if (n->prio == 2)
176 annotated_cnt++;
178 else {
179 gave_up_on = c;
180 break;
183 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
184 struct possible_tag *t = &all_matches[cur_match];
185 if (!(c->object.flags & t->flag_within))
186 t->depth++;
188 if (annotated_cnt && !list) {
189 if (debug)
190 fprintf(stderr, "finished search at %s\n",
191 sha1_to_hex(c->object.sha1));
192 break;
194 while (parents) {
195 struct commit *p = parents->item;
196 parse_commit(p);
197 if (!(p->object.flags & SEEN))
198 insert_by_date(p, &list);
199 p->object.flags |= c->object.flags;
200 parents = parents->next;
204 if (!match_cnt)
205 die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));
207 qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
209 if (gave_up_on) {
210 insert_by_date(gave_up_on, &list);
211 seen_commits--;
213 seen_commits += finish_depth_computation(&list, &all_matches[0]);
214 free_commit_list(list);
216 if (debug) {
217 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
218 struct possible_tag *t = &all_matches[cur_match];
219 fprintf(stderr, " %-11s %8d %s\n",
220 prio_names[t->name->prio],
221 t->depth, t->name->path);
223 fprintf(stderr, "traversed %lu commits\n", seen_commits);
224 if (gave_up_on) {
225 fprintf(stderr,
226 "more than %i tags found; listed %i most recent\n"
227 "gave up search at %s\n",
228 max_candidates, max_candidates,
229 sha1_to_hex(gave_up_on->object.sha1));
232 if (abbrev == 0)
233 printf("%s\n", all_matches[0].name->path );
234 else
235 printf("%s-%d-g%s\n", all_matches[0].name->path,
236 all_matches[0].depth,
237 find_unique_abbrev(cmit->object.sha1, abbrev));
239 if (!last_one)
240 clear_commit_marks(cmit, -1);
243 int cmd_describe(int argc, const char **argv, const char *prefix)
245 int i;
246 int contains = 0;
248 for (i = 1; i < argc; i++) {
249 const char *arg = argv[i];
251 if (*arg != '-')
252 break;
253 else if (!strcmp(arg, "--contains"))
254 contains = 1;
255 else if (!strcmp(arg, "--debug"))
256 debug = 1;
257 else if (!strcmp(arg, "--all"))
258 all = 1;
259 else if (!strcmp(arg, "--tags"))
260 tags = 1;
261 else if (!prefixcmp(arg, "--abbrev=")) {
262 abbrev = strtoul(arg + 9, NULL, 10);
263 if (abbrev != 0 && (abbrev < MINIMUM_ABBREV || 40 < abbrev))
264 abbrev = DEFAULT_ABBREV;
266 else if (!prefixcmp(arg, "--candidates=")) {
267 max_candidates = strtoul(arg + 13, NULL, 10);
268 if (max_candidates < 1)
269 max_candidates = 1;
270 else if (max_candidates > MAX_TAGS)
271 max_candidates = MAX_TAGS;
273 else
274 usage(describe_usage);
277 save_commit_buffer = 0;
279 if (contains) {
280 const char **args = xmalloc((4 + argc - i) * sizeof(char*));
281 args[0] = "name-rev";
282 args[1] = "--name-only";
283 args[2] = "--tags";
284 memcpy(args + 3, argv + i, (argc - i) * sizeof(char*));
285 args[3 + argc - i] = NULL;
286 return cmd_name_rev(3 + argc - i, args, prefix);
289 if (argc <= i)
290 describe("HEAD", 1);
291 else
292 while (i < argc) {
293 describe(argv[i], (i == argc - 1));
294 i++;
297 return 0;