#include "commit.h"
#include "tag.h"
#include "refs.h"
-#include "diff.h"
-#include "diffcore.h"
-#include "revision.h"
#include "builtin.h"
+#define SEEN (1u<<0)
+#define MAX_TAGS (FLAG_BITS - 1)
+
static const char describe_usage[] =
"git-describe [--all] [--tags] [--abbrev=<n>] <committish>*";
+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 abbrev = DEFAULT_ABBREV;
+static int max_candidates = 10;
-static unsigned int names[256], allocs[256];
-static struct commit_name {
- struct commit *commit;
+struct commit_name {
int prio; /* annotated tag = 2, tag = 1, head = 0 */
char path[FLEX_ARRAY]; /* more */
-} **name_array[256];
-
-static struct commit_name *match(struct commit *cmit)
-{
- unsigned char level0 = cmit->object.sha1[0];
- struct commit_name **p = name_array[level0];
- unsigned int hi = names[level0];
- unsigned int lo = 0;
-
- while (lo < hi) {
- unsigned int mi = (lo + hi) / 2;
- int cmp = hashcmp(p[mi]->commit->object.sha1,
- cmit->object.sha1);
- if (!cmp) {
- while (mi && p[mi - 1]->commit == cmit)
- mi--;
- return p[mi];
- }
- if (cmp > 0)
- hi = mi;
- else
- lo = mi+1;
- }
- return NULL;
-}
+};
+static const char *prio_names[] = {
+ "head", "lightweight", "annotated",
+};
static void add_to_known_names(const char *path,
struct commit *commit,
int prio)
{
- int idx;
- int len = strlen(path)+1;
- struct commit_name *name = xmalloc(sizeof(struct commit_name) + len);
- unsigned char m = commit->object.sha1[0];
-
- name->commit = commit;
- name->prio = prio;
- memcpy(name->path, path, len);
- idx = names[m];
- if (idx >= allocs[m]) {
- allocs[m] = (idx + 50) * 3 / 2;
- name_array[m] = xrealloc(name_array[m],
- allocs[m] * sizeof(*name_array));
+ 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->prio = prio;
+ memcpy(e->path, path, len);
+ commit->util = e;
}
- name_array[m][idx] = name;
- names[m] = ++idx;
}
static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
* If --tags, then any tags are used.
* Otherwise only annotated tags are used.
*/
- if (!strncmp(path, "refs/tags/", 10)) {
+ if (!prefixcmp(path, "refs/tags/")) {
if (object->type == OBJ_TAG)
prio = 2;
else
return 0;
}
-static int compare_names(const void *_a, const void *_b)
-{
- struct commit_name *a = *(struct commit_name **)_a;
- struct commit_name *b = *(struct commit_name **)_b;
- unsigned long a_date = a->commit->date;
- unsigned long b_date = b->commit->date;
- int cmp = hashcmp(a->commit->object.sha1, b->commit->object.sha1);
-
- if (cmp)
- return cmp;
- if (a->prio != b->prio)
- return b->prio - a->prio;
- return (a_date > b_date) ? -1 : (a_date == b_date) ? 0 : 1;
-}
-
struct possible_tag {
- struct possible_tag *next;
struct commit_name *name;
- unsigned long depth;
+ 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 describe(const char *arg, int last_one)
{
unsigned char sha1[20];
- struct commit *cmit;
+ struct commit *cmit, *gave_up_on = NULL;
struct commit_list *list;
static int initialized = 0;
struct commit_name *n;
- struct possible_tag *all_matches, *min_match, *cur_match;
+ 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);
die("%s is not a valid '%s' object", arg, commit_type);
if (!initialized) {
- unsigned int m;
initialized = 1;
for_each_ref(get_name, NULL);
- for (m = 0; m < ARRAY_SIZE(name_array); m++)
- qsort(name_array[m], names[m],
- sizeof(*name_array[m]), compare_names);
}
- n = match(cmit);
+ n = cmit->util;
if (n) {
printf("%s\n", n->path);
return;
}
+ if (debug)
+ fprintf(stderr, "searching to describe %s\n", arg);
+
list = NULL;
- all_matches = NULL;
- cur_match = NULL;
+ cmit->object.flags = SEEN;
commit_list_insert(cmit, &list);
while (list) {
struct commit *c = pop_commit(&list);
struct commit_list *parents = c->parents;
- n = match(c);
+ seen_commits++;
+ n = c->util;
if (n) {
- struct possible_tag *p = xmalloc(sizeof(*p));
- p->name = n;
- p->next = NULL;
- if (cur_match)
- cur_match->next = p;
- else
- all_matches = p;
- cur_match = p;
- if (n->prio == 2)
- continue;
+ 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)) {
- p->object.flags |= SEEN;
+ if (!(p->object.flags & SEEN))
insert_by_date(p, &list);
- }
+ p->object.flags |= c->object.flags;
parents = parents->next;
}
}
- if (!all_matches)
+ if (!match_cnt)
die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));
- min_match = NULL;
- for (cur_match = all_matches; cur_match; cur_match = cur_match->next) {
- struct rev_info revs;
- struct commit *tagged = cur_match->name->commit;
+ qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
- clear_commit_marks(cmit, -1);
- init_revisions(&revs, NULL);
- tagged->object.flags |= UNINTERESTING;
- add_pending_object(&revs, &tagged->object, NULL);
- add_pending_object(&revs, &cmit->object, NULL);
-
- prepare_revision_walk(&revs);
- cur_match->depth = 0;
- while ((!min_match || cur_match->depth < min_match->depth)
- && get_revision(&revs))
- cur_match->depth++;
- if (!min_match || (cur_match->depth < min_match->depth
- && cur_match->name->prio >= min_match->name->prio))
- min_match = cur_match;
- free_commit_list(revs.commits);
+ if (gave_up_on) {
+ insert_by_date(gave_up_on, &list);
+ seen_commits--;
}
- printf("%s-g%s\n", min_match->name->path,
- find_unique_abbrev(cmit->object.sha1, abbrev));
+ seen_commits += finish_depth_computation(&list, &all_matches[0]);
+ free_commit_list(list);
- if (!last_one) {
- for (cur_match = all_matches; cur_match; cur_match = min_match) {
- min_match = cur_match->next;
- free(cur_match);
+ 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));
}
- clear_commit_marks(cmit, SEEN);
}
+ if (abbrev == 0)
+ printf("%s\n", all_matches[0].name->path );
+ else
+ printf("%s-%d-g%s\n", all_matches[0].name->path,
+ all_matches[0].depth,
+ find_unique_abbrev(cmit->object.sha1, abbrev));
+
+ if (!last_one)
+ clear_commit_marks(cmit, -1);
}
int cmd_describe(int argc, const char **argv, const char *prefix)
if (*arg != '-')
break;
+ else if (!strcmp(arg, "--debug"))
+ debug = 1;
else if (!strcmp(arg, "--all"))
all = 1;
else if (!strcmp(arg, "--tags"))
tags = 1;
- else if (!strncmp(arg, "--abbrev=", 9)) {
+ else if (!prefixcmp(arg, "--abbrev=")) {
abbrev = strtoul(arg + 9, NULL, 10);
- if (abbrev < MINIMUM_ABBREV || 40 < abbrev)
+ if (abbrev != 0 && (abbrev < MINIMUM_ABBREV || 40 < abbrev))
abbrev = DEFAULT_ABBREV;
}
+ else if (!prefixcmp(arg, "--candidates=")) {
+ max_candidates = strtoul(arg + 13, NULL, 10);
+ if (max_candidates < 1)
+ max_candidates = 1;
+ else if (max_candidates > MAX_TAGS)
+ max_candidates = MAX_TAGS;
+ }
else
usage(describe_usage);
}