reflog-walk: build fixes
[git/dscho.git] / builtin-describe.c
blobe7b8f95c81eb844d152b58e539e586ab4ddada41
1 #include "cache.h"
2 #include "commit.h"
3 #include "tag.h"
4 #include "refs.h"
5 #include "builtin.h"
7 #define SEEN (1u<<0)
8 #define MAX_TAGS (FLAG_BITS - 1)
10 static const char describe_usage[] =
11 "git-describe [--all] [--tags] [--abbrev=<n>] <committish>*";
13 static int debug; /* Display lots of verbose info */
14 static int all; /* Default to annotated tags only */
15 static int tags; /* But allow any tags if --tags is specified */
16 static int abbrev = DEFAULT_ABBREV;
17 static int max_candidates = 10;
19 struct commit_name {
20 int prio; /* annotated tag = 2, tag = 1, head = 0 */
21 char path[FLEX_ARRAY]; /* more */
23 static const char *prio_names[] = {
24 "head", "lightweight", "annotated",
27 static void add_to_known_names(const char *path,
28 struct commit *commit,
29 int prio)
31 struct commit_name *e = commit->util;
32 if (!e || e->prio < prio) {
33 size_t len = strlen(path)+1;
34 free(e);
35 e = xmalloc(sizeof(struct commit_name) + len);
36 e->prio = prio;
37 memcpy(e->path, path, len);
38 commit->util = e;
42 static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
44 struct commit *commit = lookup_commit_reference_gently(sha1, 1);
45 struct object *object;
46 int prio;
48 if (!commit)
49 return 0;
50 object = parse_object(sha1);
51 /* If --all, then any refs are used.
52 * If --tags, then any tags are used.
53 * Otherwise only annotated tags are used.
55 if (!strncmp(path, "refs/tags/", 10)) {
56 if (object->type == OBJ_TAG)
57 prio = 2;
58 else
59 prio = 1;
61 else
62 prio = 0;
64 if (!all) {
65 if (!prio)
66 return 0;
67 if (!tags && prio < 2)
68 return 0;
70 add_to_known_names(all ? path + 5 : path + 10, commit, prio);
71 return 0;
74 struct possible_tag {
75 struct commit_name *name;
76 int depth;
77 int found_order;
78 unsigned flag_within;
81 static int compare_pt(const void *a_, const void *b_)
83 struct possible_tag *a = (struct possible_tag *)a_;
84 struct possible_tag *b = (struct possible_tag *)b_;
85 if (a->name->prio != b->name->prio)
86 return b->name->prio - a->name->prio;
87 if (a->depth != b->depth)
88 return a->depth - b->depth;
89 if (a->found_order != b->found_order)
90 return a->found_order - b->found_order;
91 return 0;
94 static void describe(const char *arg, int last_one)
96 unsigned char sha1[20];
97 struct commit *cmit, *gave_up_on = NULL;
98 struct commit_list *list;
99 static int initialized = 0;
100 struct commit_name *n;
101 struct possible_tag all_matches[MAX_TAGS];
102 unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
103 unsigned long seen_commits = 0;
104 int found = 0;
106 if (get_sha1(arg, sha1))
107 die("Not a valid object name %s", arg);
108 cmit = lookup_commit_reference(sha1);
109 if (!cmit)
110 die("%s is not a valid '%s' object", arg, commit_type);
112 if (!initialized) {
113 initialized = 1;
114 for_each_ref(get_name, NULL);
117 n = cmit->util;
118 if (n) {
119 printf("%s\n", n->path);
120 return;
123 if (debug)
124 fprintf(stderr, "searching to describe %s\n", arg);
126 list = NULL;
127 cmit->object.flags = SEEN;
128 commit_list_insert(cmit, &list);
129 while (list) {
130 struct commit *c = pop_commit(&list);
131 struct commit_list *parents = c->parents;
132 seen_commits++;
133 n = c->util;
134 if (n) {
135 if (match_cnt < max_candidates) {
136 struct possible_tag *t = &all_matches[match_cnt++];
137 t->name = n;
138 t->depth = seen_commits - 1;
139 t->flag_within = 1u << match_cnt;
140 t->found_order = found++;
141 c->object.flags |= t->flag_within;
142 if (n->prio == 2)
143 annotated_cnt++;
145 else {
146 gave_up_on = c;
147 break;
150 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
151 struct possible_tag *t = &all_matches[cur_match];
152 if (!(c->object.flags & t->flag_within))
153 t->depth++;
155 if (annotated_cnt && !list) {
156 if (debug)
157 fprintf(stderr, "finished search at %s\n",
158 sha1_to_hex(c->object.sha1));
159 break;
161 while (parents) {
162 struct commit *p = parents->item;
163 parse_commit(p);
164 if (!(p->object.flags & SEEN))
165 insert_by_date(p, &list);
166 p->object.flags |= c->object.flags;
167 parents = parents->next;
170 free_commit_list(list);
172 if (!match_cnt)
173 die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));
175 qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
176 if (debug) {
177 for (cur_match = 0; cur_match < match_cnt; cur_match++) {
178 struct possible_tag *t = &all_matches[cur_match];
179 fprintf(stderr, " %-11s %8d %s\n",
180 prio_names[t->name->prio],
181 t->depth, t->name->path);
183 fprintf(stderr, "traversed %lu commits\n", seen_commits);
184 if (gave_up_on) {
185 fprintf(stderr,
186 "more than %i tags found; listed %i most recent\n"
187 "gave up search at %s\n",
188 max_candidates, max_candidates,
189 sha1_to_hex(gave_up_on->object.sha1));
192 printf("%s-g%s\n", all_matches[0].name->path,
193 find_unique_abbrev(cmit->object.sha1, abbrev));
195 if (!last_one)
196 clear_commit_marks(cmit, -1);
199 int cmd_describe(int argc, const char **argv, const char *prefix)
201 int i;
203 for (i = 1; i < argc; i++) {
204 const char *arg = argv[i];
206 if (*arg != '-')
207 break;
208 else if (!strcmp(arg, "--debug"))
209 debug = 1;
210 else if (!strcmp(arg, "--all"))
211 all = 1;
212 else if (!strcmp(arg, "--tags"))
213 tags = 1;
214 else if (!strncmp(arg, "--abbrev=", 9)) {
215 abbrev = strtoul(arg + 9, NULL, 10);
216 if (abbrev < MINIMUM_ABBREV || 40 < abbrev)
217 abbrev = DEFAULT_ABBREV;
219 else if (!strncmp(arg, "--candidates=", 13)) {
220 max_candidates = strtoul(arg + 13, NULL, 10);
221 if (max_candidates < 1)
222 max_candidates = 1;
223 else if (max_candidates > MAX_TAGS)
224 max_candidates = MAX_TAGS;
226 else
227 usage(describe_usage);
230 save_commit_buffer = 0;
232 if (argc <= i)
233 describe("HEAD", 1);
234 else
235 while (i < argc) {
236 describe(argv[i], (i == argc - 1));
237 i++;
240 return 0;