git/builtin/name-rev.c

637 строки
16 KiB
C

#include "builtin.h"
#include "cache.h"
#include "repository.h"
#include "config.h"
#include "commit.h"
#include "tag.h"
#include "refs.h"
#include "parse-options.h"
#include "prio-queue.h"
#include "hash-lookup.h"
#include "commit-slab.h"
/*
* One day. See the 'name a rev shortly after epoch' test in t6120 when
* changing this value
*/
#define CUTOFF_DATE_SLOP 86400
struct rev_name {
char *tip_name;
timestamp_t taggerdate;
int generation;
int distance;
int from_tag;
};
define_commit_slab(commit_rev_name, struct rev_name);
static timestamp_t cutoff = TIME_MAX;
static struct commit_rev_name rev_names;
/* How many generations are maximally preferred over _one_ merge traversal? */
#define MERGE_TRAVERSAL_WEIGHT 65535
static int is_valid_rev_name(const struct rev_name *name)
{
return name && (name->generation || name->tip_name);
}
static struct rev_name *get_commit_rev_name(const struct commit *commit)
{
struct rev_name *name = commit_rev_name_peek(&rev_names, commit);
return is_valid_rev_name(name) ? name : NULL;
}
static int is_better_name(struct rev_name *name,
timestamp_t taggerdate,
int distance,
int from_tag)
{
/*
* When comparing names based on tags, prefer names
* based on the older tag, even if it is farther away.
*/
if (from_tag && name->from_tag)
return (name->taggerdate > taggerdate ||
(name->taggerdate == taggerdate &&
name->distance > distance));
/*
* We know that at least one of them is a non-tag at this point.
* favor a tag over a non-tag.
*/
if (name->from_tag != from_tag)
return from_tag;
/*
* We are now looking at two non-tags. Tiebreak to favor
* shorter hops.
*/
if (name->distance != distance)
return name->distance > distance;
/* ... or tiebreak to favor older date */
if (name->taggerdate != taggerdate)
return name->taggerdate > taggerdate;
/* keep the current one if we cannot decide */
return 0;
}
static struct rev_name *create_or_update_name(struct commit *commit,
timestamp_t taggerdate,
int generation, int distance,
int from_tag)
{
struct rev_name *name = commit_rev_name_at(&rev_names, commit);
if (is_valid_rev_name(name)) {
if (!is_better_name(name, taggerdate, distance, from_tag))
return NULL;
/*
* This string might still be shared with ancestors
* (generation > 0). We can release it here regardless,
* because the new name that has just won will be better
* for them as well, so name_rev() will replace these
* stale pointers when it processes the parents.
*/
if (!name->generation)
free(name->tip_name);
}
name->taggerdate = taggerdate;
name->generation = generation;
name->distance = distance;
name->from_tag = from_tag;
return name;
}
static char *get_parent_name(const struct rev_name *name, int parent_number)
{
struct strbuf sb = STRBUF_INIT;
size_t len;
strip_suffix(name->tip_name, "^0", &len);
if (name->generation > 0) {
strbuf_grow(&sb, len +
1 + decimal_width(name->generation) +
1 + decimal_width(parent_number));
strbuf_addf(&sb, "%.*s~%d^%d", (int)len, name->tip_name,
name->generation, parent_number);
} else {
strbuf_grow(&sb, len +
1 + decimal_width(parent_number));
strbuf_addf(&sb, "%.*s^%d", (int)len, name->tip_name,
parent_number);
}
return strbuf_detach(&sb, NULL);
}
static void name_rev(struct commit *start_commit,
const char *tip_name, timestamp_t taggerdate,
int from_tag, int deref)
{
struct prio_queue queue;
struct commit *commit;
struct commit **parents_to_queue = NULL;
size_t parents_to_queue_nr, parents_to_queue_alloc = 0;
struct rev_name *start_name;
parse_commit(start_commit);
if (start_commit->date < cutoff)
return;
start_name = create_or_update_name(start_commit, taggerdate, 0, 0,
from_tag);
if (!start_name)
return;
if (deref)
start_name->tip_name = xstrfmt("%s^0", tip_name);
else
start_name->tip_name = xstrdup(tip_name);
memset(&queue, 0, sizeof(queue)); /* Use the prio_queue as LIFO */
prio_queue_put(&queue, start_commit);
while ((commit = prio_queue_get(&queue))) {
struct rev_name *name = get_commit_rev_name(commit);
struct commit_list *parents;
int parent_number = 1;
parents_to_queue_nr = 0;
for (parents = commit->parents;
parents;
parents = parents->next, parent_number++) {
struct commit *parent = parents->item;
struct rev_name *parent_name;
int generation, distance;
parse_commit(parent);
if (parent->date < cutoff)
continue;
if (parent_number > 1) {
generation = 0;
distance = name->distance + MERGE_TRAVERSAL_WEIGHT;
} else {
generation = name->generation + 1;
distance = name->distance + 1;
}
parent_name = create_or_update_name(parent, taggerdate,
generation,
distance, from_tag);
if (parent_name) {
if (parent_number > 1)
parent_name->tip_name =
get_parent_name(name,
parent_number);
else
parent_name->tip_name = name->tip_name;
ALLOC_GROW(parents_to_queue,
parents_to_queue_nr + 1,
parents_to_queue_alloc);
parents_to_queue[parents_to_queue_nr] = parent;
parents_to_queue_nr++;
}
}
/* The first parent must come out first from the prio_queue */
while (parents_to_queue_nr)
prio_queue_put(&queue,
parents_to_queue[--parents_to_queue_nr]);
}
clear_prio_queue(&queue);
free(parents_to_queue);
}
static int subpath_matches(const char *path, const char *filter)
{
const char *subpath = path;
while (subpath) {
if (!wildmatch(filter, subpath, 0))
return subpath - path;
subpath = strchr(subpath, '/');
if (subpath)
subpath++;
}
return -1;
}
static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
{
if (shorten_unambiguous)
refname = shorten_unambiguous_ref(refname, 0);
else if (skip_prefix(refname, "refs/heads/", &refname))
; /* refname already advanced */
else
skip_prefix(refname, "refs/", &refname);
return refname;
}
struct name_ref_data {
int tags_only;
int name_only;
struct string_list ref_filters;
struct string_list exclude_filters;
};
static struct tip_table {
struct tip_table_entry {
struct object_id oid;
const char *refname;
struct commit *commit;
timestamp_t taggerdate;
unsigned int from_tag:1;
unsigned int deref:1;
} *table;
int nr;
int alloc;
int sorted;
} tip_table;
static void add_to_tip_table(const struct object_id *oid, const char *refname,
int shorten_unambiguous, struct commit *commit,
timestamp_t taggerdate, int from_tag, int deref)
{
refname = name_ref_abbrev(refname, shorten_unambiguous);
ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
oidcpy(&tip_table.table[tip_table.nr].oid, oid);
tip_table.table[tip_table.nr].refname = xstrdup(refname);
tip_table.table[tip_table.nr].commit = commit;
tip_table.table[tip_table.nr].taggerdate = taggerdate;
tip_table.table[tip_table.nr].from_tag = from_tag;
tip_table.table[tip_table.nr].deref = deref;
tip_table.nr++;
tip_table.sorted = 0;
}
static int tipcmp(const void *a_, const void *b_)
{
const struct tip_table_entry *a = a_, *b = b_;
return oidcmp(&a->oid, &b->oid);
}
static int cmp_by_tag_and_age(const void *a_, const void *b_)
{
const struct tip_table_entry *a = a_, *b = b_;
int cmp;
/* Prefer tags. */
cmp = b->from_tag - a->from_tag;
if (cmp)
return cmp;
/* Older is better. */
if (a->taggerdate < b->taggerdate)
return -1;
return a->taggerdate != b->taggerdate;
}
static int name_ref(const char *path, const struct object_id *oid, int flags, void *cb_data)
{
struct object *o = parse_object(the_repository, oid);
struct name_ref_data *data = cb_data;
int can_abbreviate_output = data->tags_only && data->name_only;
int deref = 0;
int from_tag = 0;
struct commit *commit = NULL;
timestamp_t taggerdate = TIME_MAX;
if (data->tags_only && !starts_with(path, "refs/tags/"))
return 0;
if (data->exclude_filters.nr) {
struct string_list_item *item;
for_each_string_list_item(item, &data->exclude_filters) {
if (subpath_matches(path, item->string) >= 0)
return 0;
}
}
if (data->ref_filters.nr) {
struct string_list_item *item;
int matched = 0;
/* See if any of the patterns match. */
for_each_string_list_item(item, &data->ref_filters) {
/*
* Check all patterns even after finding a match, so
* that we can see if a match with a subpath exists.
* When a user asked for 'refs/tags/v*' and 'v1.*',
* both of which match, the user is showing her
* willingness to accept a shortened output by having
* the 'v1.*' in the acceptable refnames, so we
* shouldn't stop when seeing 'refs/tags/v1.4' matches
* 'refs/tags/v*'. We should show it as 'v1.4'.
*/
switch (subpath_matches(path, item->string)) {
case -1: /* did not match */
break;
case 0: /* matched fully */
matched = 1;
break;
default: /* matched subpath */
matched = 1;
can_abbreviate_output = 1;
break;
}
}
/* If none of the patterns matched, stop now */
if (!matched)
return 0;
}
while (o && o->type == OBJ_TAG) {
struct tag *t = (struct tag *) o;
if (!t->tagged)
break; /* broken repository */
o = parse_object(the_repository, &t->tagged->oid);
deref = 1;
taggerdate = t->date;
}
if (o && o->type == OBJ_COMMIT) {
commit = (struct commit *)o;
from_tag = starts_with(path, "refs/tags/");
if (taggerdate == TIME_MAX)
taggerdate = commit->date;
}
add_to_tip_table(oid, path, can_abbreviate_output, commit, taggerdate,
from_tag, deref);
return 0;
}
static void name_tips(void)
{
int i;
/*
* Try to set better names first, so that worse ones spread
* less.
*/
QSORT(tip_table.table, tip_table.nr, cmp_by_tag_and_age);
for (i = 0; i < tip_table.nr; i++) {
struct tip_table_entry *e = &tip_table.table[i];
if (e->commit) {
name_rev(e->commit, e->refname, e->taggerdate,
e->from_tag, e->deref);
}
}
}
static const struct object_id *nth_tip_table_ent(size_t ix, const void *table_)
{
const struct tip_table_entry *table = table_;
return &table[ix].oid;
}
static const char *get_exact_ref_match(const struct object *o)
{
int found;
if (!tip_table.table || !tip_table.nr)
return NULL;
if (!tip_table.sorted) {
QSORT(tip_table.table, tip_table.nr, tipcmp);
tip_table.sorted = 1;
}
found = oid_pos(&o->oid, tip_table.table, tip_table.nr,
nth_tip_table_ent);
if (0 <= found)
return tip_table.table[found].refname;
return NULL;
}
/* may return a constant string or use "buf" as scratch space */
static const char *get_rev_name(const struct object *o, struct strbuf *buf)
{
struct rev_name *n;
const struct commit *c;
if (o->type != OBJ_COMMIT)
return get_exact_ref_match(o);
c = (const struct commit *) o;
n = get_commit_rev_name(c);
if (!n)
return NULL;
if (!n->generation)
return n->tip_name;
else {
strbuf_reset(buf);
strbuf_addstr(buf, n->tip_name);
strbuf_strip_suffix(buf, "^0");
strbuf_addf(buf, "~%d", n->generation);
return buf->buf;
}
}
static void show_name(const struct object *obj,
const char *caller_name,
int always, int allow_undefined, int name_only)
{
const char *name;
const struct object_id *oid = &obj->oid;
struct strbuf buf = STRBUF_INIT;
if (!name_only)
printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
name = get_rev_name(obj, &buf);
if (name)
printf("%s\n", name);
else if (allow_undefined)
printf("undefined\n");
else if (always)
printf("%s\n", find_unique_abbrev(oid, DEFAULT_ABBREV));
else
die("cannot describe '%s'", oid_to_hex(oid));
strbuf_release(&buf);
}
static char const * const name_rev_usage[] = {
N_("git name-rev [<options>] <commit>..."),
N_("git name-rev [<options>] --all"),
N_("git name-rev [<options>] --stdin"),
NULL
};
static void name_rev_line(char *p, struct name_ref_data *data)
{
struct strbuf buf = STRBUF_INIT;
int counter = 0;
char *p_start;
const unsigned hexsz = the_hash_algo->hexsz;
for (p_start = p; *p; p++) {
#define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
if (!ishex(*p))
counter = 0;
else if (++counter == hexsz &&
!ishex(*(p+1))) {
struct object_id oid;
const char *name = NULL;
char c = *(p+1);
int p_len = p - p_start + 1;
counter = 0;
*(p+1) = 0;
if (!get_oid(p - (hexsz - 1), &oid)) {
struct object *o =
lookup_object(the_repository, &oid);
if (o)
name = get_rev_name(o, &buf);
}
*(p+1) = c;
if (!name)
continue;
if (data->name_only)
printf("%.*s%s", p_len - hexsz, p_start, name);
else
printf("%.*s (%s)", p_len, p_start, name);
p_start = p + 1;
}
}
/* flush */
if (p_start != p)
fwrite(p_start, p - p_start, 1, stdout);
strbuf_release(&buf);
}
int cmd_name_rev(int argc, const char **argv, const char *prefix)
{
struct object_array revs = OBJECT_ARRAY_INIT;
int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
struct name_ref_data data = { 0, 0, STRING_LIST_INIT_NODUP, STRING_LIST_INIT_NODUP };
struct option opts[] = {
OPT_BOOL(0, "name-only", &data.name_only, N_("print only ref-based names (no object names)")),
OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
OPT_STRING_LIST(0, "refs", &data.ref_filters, N_("pattern"),
N_("only use refs matching <pattern>")),
OPT_STRING_LIST(0, "exclude", &data.exclude_filters, N_("pattern"),
N_("ignore refs matching <pattern>")),
OPT_GROUP(""),
OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
OPT_BOOL(0, "always", &always,
N_("show abbreviated commit object as fallback")),
{
/* A Hidden OPT_BOOL */
OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
N_("dereference tags in the input (internal use)"),
PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
},
OPT_END(),
};
init_commit_rev_name(&rev_names);
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
if (all + transform_stdin + !!argc > 1) {
error("Specify either a list, or --all, not both!");
usage_with_options(name_rev_usage, opts);
}
if (all || transform_stdin)
cutoff = 0;
for (; argc; argc--, argv++) {
struct object_id oid;
struct object *object;
struct commit *commit;
if (get_oid(*argv, &oid)) {
fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
*argv);
continue;
}
commit = NULL;
object = parse_object(the_repository, &oid);
if (object) {
struct object *peeled = deref_tag(the_repository,
object, *argv, 0);
if (peeled && peeled->type == OBJ_COMMIT)
commit = (struct commit *)peeled;
}
if (!object) {
fprintf(stderr, "Could not get object for %s. Skipping.\n",
*argv);
continue;
}
if (commit) {
if (cutoff > commit->date)
cutoff = commit->date;
}
if (peel_tag) {
if (!commit) {
fprintf(stderr, "Could not get commit for %s. Skipping.\n",
*argv);
continue;
}
object = (struct object *)commit;
}
add_object_array(object, *argv, &revs);
}
if (cutoff) {
/* check for undeflow */
if (cutoff > TIME_MIN + CUTOFF_DATE_SLOP)
cutoff = cutoff - CUTOFF_DATE_SLOP;
else
cutoff = TIME_MIN;
}
for_each_ref(name_ref, &data);
name_tips();
if (transform_stdin) {
char buffer[2048];
while (!feof(stdin)) {
char *p = fgets(buffer, sizeof(buffer), stdin);
if (!p)
break;
name_rev_line(p, &data);
}
} else if (all) {
int i, max;
max = get_max_object_index();
for (i = 0; i < max; i++) {
struct object *obj = get_indexed_object(i);
if (!obj || obj->type != OBJ_COMMIT)
continue;
show_name(obj, NULL,
always, allow_undefined, data.name_only);
}
} else {
int i;
for (i = 0; i < revs.nr; i++)
show_name(revs.objects[i].item, revs.objects[i].name,
always, allow_undefined, data.name_only);
}
UNLEAK(revs);
return 0;
}