git/builtin/describe.c
Michael Haggerty 697cc8efd9 lockfile.h: extract new header file for the functions in lockfile.c
Move the interface declaration for the functions in lockfile.c from
cache.h to a new file, lockfile.h. Add #includes where necessary (and
remove some redundant includes of cache.h by files that already
include builtin.h).

Move the documentation of the lock_file state diagram from lockfile.c
to the new header file.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:56:14 -07:00

483 lines
12 KiB
C

#include "cache.h"
#include "lockfile.h"
#include "commit.h"
#include "tag.h"
#include "refs.h"
#include "builtin.h"
#include "exec_cmd.h"
#include "parse-options.h"
#include "diff.h"
#include "hashmap.h"
#include "argv-array.h"
#define SEEN (1u << 0)
#define MAX_TAGS (FLAG_BITS - 1)
static const char * const describe_usage[] = {
N_("git describe [options] <commit-ish>*"),
N_("git describe [options] --dirty"),
NULL
};
static int debug; /* Display lots of verbose info */
static int all; /* Any valid ref can be used */
static int tags; /* Allow lightweight tags */
static int longformat;
static int first_parent;
static int abbrev = -1; /* unspecified */
static int max_candidates = 10;
static struct hashmap names;
static int have_util;
static const char *pattern;
static int always;
static const char *dirty;
/* diff-index command arguments to check if working tree is dirty. */
static const char *diff_index_args[] = {
"diff-index", "--quiet", "HEAD", "--", NULL
};
struct commit_name {
struct hashmap_entry entry;
unsigned char peeled[20];
struct tag *tag;
unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
unsigned name_checked:1;
unsigned char sha1[20];
char *path;
};
static const char *prio_names[] = {
"head", "lightweight", "annotated",
};
static int commit_name_cmp(const struct commit_name *cn1,
const struct commit_name *cn2, const void *peeled)
{
return hashcmp(cn1->peeled, peeled ? peeled : cn2->peeled);
}
static inline struct commit_name *find_commit_name(const unsigned char *peeled)
{
return hashmap_get_from_hash(&names, sha1hash(peeled), peeled);
}
static int replace_name(struct commit_name *e,
int prio,
const unsigned char *sha1,
struct tag **tag)
{
if (!e || e->prio < prio)
return 1;
if (e->prio == 2 && prio == 2) {
/* Multiple annotated tags point to the same commit.
* Select one to keep based upon their tagger date.
*/
struct tag *t;
if (!e->tag) {
t = lookup_tag(e->sha1);
if (!t || parse_tag(t))
return 1;
e->tag = t;
}
t = lookup_tag(sha1);
if (!t || parse_tag(t))
return 0;
*tag = t;
if (e->tag->date < t->date)
return 1;
}
return 0;
}
static void add_to_known_names(const char *path,
const unsigned char *peeled,
int prio,
const unsigned char *sha1)
{
struct commit_name *e = find_commit_name(peeled);
struct tag *tag = NULL;
if (replace_name(e, prio, sha1, &tag)) {
if (!e) {
e = xmalloc(sizeof(struct commit_name));
hashcpy(e->peeled, peeled);
hashmap_entry_init(e, sha1hash(peeled));
hashmap_add(&names, e);
e->path = NULL;
}
e->tag = tag;
e->prio = prio;
e->name_checked = 0;
hashcpy(e->sha1, sha1);
free(e->path);
e->path = xstrdup(path);
}
}
static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
{
int is_tag = starts_with(path, "refs/tags/");
unsigned char peeled[20];
int is_annotated, prio;
/* Reject anything outside refs/tags/ unless --all */
if (!all && !is_tag)
return 0;
/* Accept only tags that match the pattern, if given */
if (pattern && (!is_tag || wildmatch(pattern, path + 10, 0, NULL)))
return 0;
/* Is it annotated? */
if (!peel_ref(path, peeled)) {
is_annotated = !!hashcmp(sha1, peeled);
} else {
hashcpy(peeled, sha1);
is_annotated = 0;
}
/*
* By default, we only use annotated tags, but with --tags
* we fall back to lightweight ones (even without --tags,
* we still remember lightweight ones, only to give hints
* in an error message). --all allows any refs to be used.
*/
if (is_annotated)
prio = 2;
else if (is_tag)
prio = 1;
else
prio = 0;
add_to_known_names(all ? path + 5 : path + 10, peeled, 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->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))
commit_list_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))
die(_("annotated tag %s not available"), n->path);
}
if (n->tag && !n->name_checked) {
if (!n->tag->tag)
die(_("annotated tag %s has no embedded name"), n->path);
if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
warning(_("tag '%s' is really '%s' here"), n->tag->tag, n->path);
n->name_checked = 1;
}
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;
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;
unsigned int unannotated_cnt = 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);
n = find_commit_name(cmit->object.sha1);
if (n && (tags || all || n->prio == 2)) {
/*
* Exact match to an existing ref.
*/
display_name(n);
if (longformat)
show_suffix(0, n->tag ? n->tag->tagged->sha1 : sha1);
if (dirty)
printf("%s", dirty);
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);
if (!have_util) {
struct hashmap_iter iter;
struct commit *c;
struct commit_name *n = hashmap_iter_first(&names, &iter);
for (; n; n = hashmap_iter_next(&iter)) {
c = lookup_commit_reference_gently(n->peeled, 1);
if (c)
c->util = n;
}
have_util = 1;
}
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 (!tags && !all && n->prio < 2) {
unannotated_cnt++;
} else 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))
commit_list_insert_by_date(p, &list);
p->object.flags |= c->object.flags;
parents = parents->next;
if (first_parent)
break;
}
}
if (!match_cnt) {
const unsigned char *sha1 = cmit->object.sha1;
if (always) {
printf("%s", find_unique_abbrev(sha1, abbrev));
if (dirty)
printf("%s", dirty);
printf("\n");
return;
}
if (unannotated_cnt)
die(_("No annotated tags can describe '%s'.\n"
"However, there were unannotated tags: try --tags."),
sha1_to_hex(sha1));
else
die(_("No tags can describe '%s'.\n"
"Try --always, or create some tags."),
sha1_to_hex(sha1));
}
qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
if (gave_up_on) {
commit_list_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);
if (dirty)
printf("%s", dirty);
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_BOOL(0, "contains", &contains, N_("find the tag that comes after the commit")),
OPT_BOOL(0, "debug", &debug, N_("debug search strategy on stderr")),
OPT_BOOL(0, "all", &all, N_("use any ref")),
OPT_BOOL(0, "tags", &tags, N_("use any tag, even unannotated")),
OPT_BOOL(0, "long", &longformat, N_("always use long format")),
OPT_BOOL(0, "first-parent", &first_parent, N_("only follow first parent")),
OPT__ABBREV(&abbrev),
OPT_SET_INT(0, "exact-match", &max_candidates,
N_("only output exact matches"), 0),
OPT_INTEGER(0, "candidates", &max_candidates,
N_("consider <n> most recent tags (default: 10)")),
OPT_STRING(0, "match", &pattern, N_("pattern"),
N_("only consider tags matching <pattern>")),
OPT_BOOL(0, "always", &always,
N_("show abbreviated commit object as fallback")),
{OPTION_STRING, 0, "dirty", &dirty, N_("mark"),
N_("append <mark> on dirty working tree (default: \"-dirty\")"),
PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
OPT_END(),
};
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
if (abbrev < 0)
abbrev = DEFAULT_ABBREV;
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) {
struct argv_array args;
argv_array_init(&args);
argv_array_pushl(&args, "name-rev",
"--peel-tag", "--name-only", "--no-undefined",
NULL);
if (always)
argv_array_push(&args, "--always");
if (!all) {
argv_array_push(&args, "--tags");
if (pattern)
argv_array_pushf(&args, "--refs=refs/tags/%s", pattern);
}
while (*argv) {
argv_array_push(&args, *argv);
argv++;
}
return cmd_name_rev(args.argc, args.argv, prefix);
}
hashmap_init(&names, (hashmap_cmp_fn) commit_name_cmp, 0);
for_each_rawref(get_name, NULL);
if (!names.size && !always)
die(_("No names found, cannot describe anything."));
if (argc == 0) {
if (dirty) {
static struct lock_file index_lock;
int fd;
read_cache_preload(NULL);
refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED,
NULL, NULL, NULL);
fd = hold_locked_index(&index_lock, 0);
if (0 <= fd)
update_index_if_able(&the_index, &index_lock);
if (!cmd_diff_index(ARRAY_SIZE(diff_index_args) - 1,
diff_index_args, prefix))
dirty = NULL;
}
describe("HEAD", 1);
} else if (dirty) {
die(_("--dirty is incompatible with commit-ishes"));
} else {
while (argc-- > 0)
describe(*argv++, argc == 0);
}
return 0;
}