diff options
Diffstat (limited to 'builtin-describe.c')
| -rw-r--r-- | builtin-describe.c | 367 |
1 files changed, 367 insertions, 0 deletions
diff --git a/builtin-describe.c b/builtin-describe.c new file mode 100644 index 0000000000..e515f9ca9b --- /dev/null +++ b/builtin-describe.c @@ -0,0 +1,367 @@ +#include "cache.h" +#include "commit.h" +#include "tag.h" +#include "refs.h" +#include "builtin.h" +#include "exec_cmd.h" +#include "parse-options.h" + +#define SEEN (1u<<0) +#define MAX_TAGS (FLAG_BITS - 1) + +static const char * const describe_usage[] = { + "git-describe [options] <committish>*", + NULL +}; + +static int debug; /* Display lots of verbose info */ +static int all; /* Default to annotated tags only */ +static int tags; /* But allow any tags if --tags is specified */ +static int longformat; +static int abbrev = DEFAULT_ABBREV; +static int max_candidates = 10; +const char *pattern = NULL; +static int always; + +struct commit_name { + struct tag *tag; + int prio; /* annotated tag = 2, tag = 1, head = 0 */ + unsigned char sha1[20]; + char path[FLEX_ARRAY]; /* more */ +}; +static const char *prio_names[] = { + "head", "lightweight", "annotated", +}; + +static void add_to_known_names(const char *path, + struct commit *commit, + int prio, + const unsigned char *sha1) +{ + struct commit_name *e = commit->util; + if (!e || e->prio < prio) { + size_t len = strlen(path)+1; + free(e); + e = xmalloc(sizeof(struct commit_name) + len); + e->tag = NULL; + e->prio = prio; + hashcpy(e->sha1, sha1); + memcpy(e->path, path, len); + commit->util = e; + } +} + +static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data) +{ + int might_be_tag = !prefixcmp(path, "refs/tags/"); + struct commit *commit; + struct object *object; + unsigned char peeled[20]; + int is_tag, prio; + + if (!all && !might_be_tag) + return 0; + + if (!peel_ref(path, peeled) && !is_null_sha1(peeled)) { + commit = lookup_commit_reference_gently(peeled, 1); + if (!commit) + return 0; + is_tag = !!hashcmp(sha1, commit->object.sha1); + } else { + commit = lookup_commit_reference_gently(sha1, 1); + object = parse_object(sha1); + if (!commit || !object) + return 0; + is_tag = object->type == OBJ_TAG; + } + + /* If --all, then any refs are used. + * If --tags, then any tags are used. + * Otherwise only annotated tags are used. + */ + if (might_be_tag) { + if (is_tag) + prio = 2; + else + prio = 1; + + if (pattern && fnmatch(pattern, path + 10, 0)) + prio = 0; + } + else + prio = 0; + + if (!all) { + if (!prio) + return 0; + if (!tags && prio < 2) + return 0; + } + add_to_known_names(all ? path + 5 : path + 10, commit, prio, sha1); + return 0; +} + +struct possible_tag { + struct commit_name *name; + int depth; + int found_order; + unsigned flag_within; +}; + +static int compare_pt(const void *a_, const void *b_) +{ + struct possible_tag *a = (struct possible_tag *)a_; + struct possible_tag *b = (struct possible_tag *)b_; + if (a->name->prio != b->name->prio) + return b->name->prio - a->name->prio; + if (a->depth != b->depth) + return a->depth - b->depth; + if (a->found_order != b->found_order) + return a->found_order - b->found_order; + return 0; +} + +static unsigned long finish_depth_computation( + struct commit_list **list, + struct possible_tag *best) +{ + unsigned long seen_commits = 0; + while (*list) { + struct commit *c = pop_commit(list); + struct commit_list *parents = c->parents; + seen_commits++; + if (c->object.flags & best->flag_within) { + struct commit_list *a = *list; + while (a) { + struct commit *i = a->item; + if (!(i->object.flags & best->flag_within)) + break; + a = a->next; + } + if (!a) + break; + } else + best->depth++; + while (parents) { + struct commit *p = parents->item; + parse_commit(p); + if (!(p->object.flags & SEEN)) + insert_by_date(p, list); + p->object.flags |= c->object.flags; + parents = parents->next; + } + } + return seen_commits; +} + +static void display_name(struct commit_name *n) +{ + if (n->prio == 2 && !n->tag) { + n->tag = lookup_tag(n->sha1); + if (!n->tag || parse_tag(n->tag) || !n->tag->tag) + die("annotated tag %s not available", n->path); + if (strcmp(n->tag->tag, n->path)) + warning("tag '%s' is really '%s' here", n->tag->tag, n->path); + } + + if (n->tag) + printf("%s", n->tag->tag); + else + printf("%s", n->path); +} + +static void show_suffix(int depth, const unsigned char *sha1) +{ + printf("-%d-g%s", depth, find_unique_abbrev(sha1, abbrev)); +} + +static void describe(const char *arg, int last_one) +{ + unsigned char sha1[20]; + struct commit *cmit, *gave_up_on = NULL; + struct commit_list *list; + static int initialized = 0; + struct commit_name *n; + struct possible_tag all_matches[MAX_TAGS]; + unsigned int match_cnt = 0, annotated_cnt = 0, cur_match; + unsigned long seen_commits = 0; + + if (get_sha1(arg, sha1)) + die("Not a valid object name %s", arg); + cmit = lookup_commit_reference(sha1); + if (!cmit) + die("%s is not a valid '%s' object", arg, commit_type); + + if (!initialized) { + initialized = 1; + for_each_ref(get_name, NULL); + } + + n = cmit->util; + if (n) { + /* + * Exact match to an existing ref. + */ + display_name(n); + if (longformat) + show_suffix(0, n->tag ? n->tag->tagged->sha1 : sha1); + printf("\n"); + return; + } + + if (!max_candidates) + die("no tag exactly matches '%s'", sha1_to_hex(cmit->object.sha1)); + if (debug) + fprintf(stderr, "searching to describe %s\n", arg); + + list = NULL; + cmit->object.flags = SEEN; + commit_list_insert(cmit, &list); + while (list) { + struct commit *c = pop_commit(&list); + struct commit_list *parents = c->parents; + seen_commits++; + n = c->util; + if (n) { + if (match_cnt < max_candidates) { + struct possible_tag *t = &all_matches[match_cnt++]; + t->name = n; + t->depth = seen_commits - 1; + t->flag_within = 1u << match_cnt; + t->found_order = match_cnt; + c->object.flags |= t->flag_within; + if (n->prio == 2) + annotated_cnt++; + } + else { + gave_up_on = c; + break; + } + } + for (cur_match = 0; cur_match < match_cnt; cur_match++) { + struct possible_tag *t = &all_matches[cur_match]; + if (!(c->object.flags & t->flag_within)) + t->depth++; + } + if (annotated_cnt && !list) { + if (debug) + fprintf(stderr, "finished search at %s\n", + sha1_to_hex(c->object.sha1)); + break; + } + while (parents) { + struct commit *p = parents->item; + parse_commit(p); + if (!(p->object.flags & SEEN)) + insert_by_date(p, &list); + p->object.flags |= c->object.flags; + parents = parents->next; + } + } + + if (!match_cnt) { + const unsigned char *sha1 = cmit->object.sha1; + if (always) { + printf("%s\n", find_unique_abbrev(sha1, abbrev)); + return; + } + die("cannot describe '%s'", sha1_to_hex(sha1)); + } + + qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt); + + if (gave_up_on) { + insert_by_date(gave_up_on, &list); + seen_commits--; + } + seen_commits += finish_depth_computation(&list, &all_matches[0]); + free_commit_list(list); + + if (debug) { + for (cur_match = 0; cur_match < match_cnt; cur_match++) { + struct possible_tag *t = &all_matches[cur_match]; + fprintf(stderr, " %-11s %8d %s\n", + prio_names[t->name->prio], + t->depth, t->name->path); + } + fprintf(stderr, "traversed %lu commits\n", seen_commits); + if (gave_up_on) { + fprintf(stderr, + "more than %i tags found; listed %i most recent\n" + "gave up search at %s\n", + max_candidates, max_candidates, + sha1_to_hex(gave_up_on->object.sha1)); + } + } + + display_name(all_matches[0].name); + if (abbrev) + show_suffix(all_matches[0].depth, cmit->object.sha1); + printf("\n"); + + if (!last_one) + clear_commit_marks(cmit, -1); +} + +int cmd_describe(int argc, const char **argv, const char *prefix) +{ + int contains = 0; + struct option options[] = { + OPT_BOOLEAN(0, "contains", &contains, "find the tag that comes after the commit"), + OPT_BOOLEAN(0, "debug", &debug, "debug search strategy on stderr"), + OPT_BOOLEAN(0, "all", &all, "use any ref in .git/refs"), + OPT_BOOLEAN(0, "tags", &tags, "use any tag in .git/refs/tags"), + OPT_BOOLEAN(0, "long", &longformat, "always use long format"), + OPT__ABBREV(&abbrev), + OPT_SET_INT(0, "exact-match", &max_candidates, + "only output exact matches", 0), + OPT_INTEGER(0, "candidates", &max_candidates, + "consider <n> most recent tags (default: 10)"), + OPT_STRING(0, "match", &pattern, "pattern", + "only consider tags matching <pattern>"), + OPT_BOOLEAN(0, "always", &always, + "show abbreviated commit object as fallback"), + OPT_END(), + }; + + argc = parse_options(argc, argv, options, describe_usage, 0); + if (max_candidates < 0) + max_candidates = 0; + else if (max_candidates > MAX_TAGS) + max_candidates = MAX_TAGS; + + save_commit_buffer = 0; + + if (longformat && abbrev == 0) + die("--long is incompatible with --abbrev=0"); + + if (contains) { + const char **args = xmalloc((7 + argc) * sizeof(char*)); + int i = 0; + args[i++] = "name-rev"; + args[i++] = "--name-only"; + args[i++] = "--no-undefined"; + if (always) + args[i++] = "--always"; + if (!all) { + args[i++] = "--tags"; + if (pattern) { + char *s = xmalloc(strlen("--refs=refs/tags/") + strlen(pattern) + 1); + sprintf(s, "--refs=refs/tags/%s", pattern); + args[i++] = s; + } + } + memcpy(args + i, argv, argc * sizeof(char*)); + args[i + argc] = NULL; + return cmd_name_rev(i + argc, args, prefix); + } + + if (argc == 0) { + describe("HEAD", 1); + } else { + while (argc-- > 0) { + describe(*argv++, argc == 0); + } + } + return 0; +} |