git/refspec.c
Junio C Hamano 8e3ec76a20 Merge branch 'jk/refspecs-negative'
"git fetch" and "git push" support negative refspecs.

* jk/refspecs-negative:
  refspec: add support for negative refspecs
2020-10-05 14:01:54 -07:00

277 lines
6.1 KiB
C

#include "cache.h"
#include "strvec.h"
#include "refs.h"
#include "refspec.h"
static struct refspec_item s_tag_refspec = {
0,
1,
0,
0,
0,
"refs/tags/*",
"refs/tags/*"
};
/* See TAG_REFSPEC for the string version */
const struct refspec_item *tag_refspec = &s_tag_refspec;
/*
* Parses the provided refspec 'refspec' and populates the refspec_item 'item'.
* Returns 1 if successful and 0 if the refspec is invalid.
*/
static int parse_refspec(struct refspec_item *item, const char *refspec, int fetch)
{
size_t llen;
int is_glob;
const char *lhs, *rhs;
int flags;
is_glob = 0;
lhs = refspec;
if (*lhs == '+') {
item->force = 1;
lhs++;
} else if (*lhs == '^') {
item->negative = 1;
lhs++;
}
rhs = strrchr(lhs, ':');
/* negative refspecs only have one side */
if (item->negative && rhs)
return 0;
/*
* Before going on, special case ":" (or "+:") as a refspec
* for pushing matching refs.
*/
if (!fetch && rhs == lhs && rhs[1] == '\0') {
item->matching = 1;
return 1;
}
if (rhs) {
size_t rlen = strlen(++rhs);
is_glob = (1 <= rlen && strchr(rhs, '*'));
item->dst = xstrndup(rhs, rlen);
} else {
item->dst = NULL;
}
llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
if (1 <= llen && memchr(lhs, '*', llen)) {
if ((rhs && !is_glob) || (!rhs && !item->negative && fetch))
return 0;
is_glob = 1;
} else if (rhs && is_glob) {
return 0;
}
item->pattern = is_glob;
item->src = xstrndup(lhs, llen);
flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
if (item->negative) {
struct object_id unused;
/*
* Negative refspecs only have a LHS, which indicates a ref
* (or pattern of refs) to exclude from other matches. This
* can either be a simple ref, or a glob pattern. Exact sha1
* match is not currently supported.
*/
if (!*item->src)
return 0; /* negative refspecs must not be empty */
else if (llen == the_hash_algo->hexsz && !get_oid_hex(item->src, &unused))
return 0; /* negative refpsecs cannot be exact sha1 */
else if (!check_refname_format(item->src, flags))
; /* valid looking ref is ok */
else
return 0;
/* the other rules below do not apply to negative refspecs */
return 1;
}
if (fetch) {
struct object_id unused;
/* LHS */
if (!*item->src)
; /* empty is ok; it means "HEAD" */
else if (llen == the_hash_algo->hexsz && !get_oid_hex(item->src, &unused))
item->exact_sha1 = 1; /* ok */
else if (!check_refname_format(item->src, flags))
; /* valid looking ref is ok */
else
return 0;
/* RHS */
if (!item->dst)
; /* missing is ok; it is the same as empty */
else if (!*item->dst)
; /* empty is ok; it means "do not store" */
else if (!check_refname_format(item->dst, flags))
; /* valid looking ref is ok */
else
return 0;
} else {
/*
* LHS
* - empty is allowed; it means delete.
* - when wildcarded, it must be a valid looking ref.
* - otherwise, it must be an extended SHA-1, but
* there is no existing way to validate this.
*/
if (!*item->src)
; /* empty is ok */
else if (is_glob) {
if (check_refname_format(item->src, flags))
return 0;
}
else
; /* anything goes, for now */
/*
* RHS
* - missing is allowed, but LHS then must be a
* valid looking ref.
* - empty is not allowed.
* - otherwise it must be a valid looking ref.
*/
if (!item->dst) {
if (check_refname_format(item->src, flags))
return 0;
} else if (!*item->dst) {
return 0;
} else {
if (check_refname_format(item->dst, flags))
return 0;
}
}
return 1;
}
int refspec_item_init(struct refspec_item *item, const char *refspec, int fetch)
{
memset(item, 0, sizeof(*item));
return parse_refspec(item, refspec, fetch);
}
void refspec_item_init_or_die(struct refspec_item *item, const char *refspec,
int fetch)
{
if (!refspec_item_init(item, refspec, fetch))
die(_("invalid refspec '%s'"), refspec);
}
void refspec_item_clear(struct refspec_item *item)
{
FREE_AND_NULL(item->src);
FREE_AND_NULL(item->dst);
item->force = 0;
item->pattern = 0;
item->matching = 0;
item->exact_sha1 = 0;
}
void refspec_init(struct refspec *rs, int fetch)
{
memset(rs, 0, sizeof(*rs));
rs->fetch = fetch;
}
static void refspec_append_nodup(struct refspec *rs, char *refspec)
{
struct refspec_item item;
refspec_item_init_or_die(&item, refspec, rs->fetch);
ALLOC_GROW(rs->items, rs->nr + 1, rs->alloc);
rs->items[rs->nr++] = item;
ALLOC_GROW(rs->raw, rs->raw_nr + 1, rs->raw_alloc);
rs->raw[rs->raw_nr++] = refspec;
}
void refspec_append(struct refspec *rs, const char *refspec)
{
refspec_append_nodup(rs, xstrdup(refspec));
}
void refspec_appendf(struct refspec *rs, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
refspec_append_nodup(rs, xstrvfmt(fmt, ap));
va_end(ap);
}
void refspec_appendn(struct refspec *rs, const char **refspecs, int nr)
{
int i;
for (i = 0; i < nr; i++)
refspec_append(rs, refspecs[i]);
}
void refspec_clear(struct refspec *rs)
{
int i;
for (i = 0; i < rs->nr; i++)
refspec_item_clear(&rs->items[i]);
FREE_AND_NULL(rs->items);
rs->alloc = 0;
rs->nr = 0;
for (i = 0; i < rs->raw_nr; i++)
free((char *)rs->raw[i]);
FREE_AND_NULL(rs->raw);
rs->raw_alloc = 0;
rs->raw_nr = 0;
rs->fetch = 0;
}
int valid_fetch_refspec(const char *fetch_refspec_str)
{
struct refspec_item refspec;
int ret = refspec_item_init(&refspec, fetch_refspec_str, REFSPEC_FETCH);
refspec_item_clear(&refspec);
return ret;
}
void refspec_ref_prefixes(const struct refspec *rs,
struct strvec *ref_prefixes)
{
int i;
for (i = 0; i < rs->nr; i++) {
const struct refspec_item *item = &rs->items[i];
const char *prefix = NULL;
if (item->exact_sha1 || item->negative)
continue;
if (rs->fetch == REFSPEC_FETCH)
prefix = item->src;
else if (item->dst)
prefix = item->dst;
else if (item->src && !item->exact_sha1)
prefix = item->src;
if (prefix) {
if (item->pattern) {
const char *glob = strchr(prefix, '*');
strvec_pushf(ref_prefixes, "%.*s",
(int)(glob - prefix),
prefix);
} else {
expand_ref_prefix(ref_prefixes, prefix);
}
}
}
}