mirror of
https://github.com/git/git
synced 2024-11-05 18:59:29 +00:00
65904b8b2b
Previously, when promisor_remote_move_to_tail() is called for a promisor_remote which is currently the final element in promisors, a cycle is created in the promisors linked list. This cycle leads to a double free later on in promisor_remote_clear() when the final element of the promisors list is removed: promisors is set to promisors->next (a no-op, as promisors->next == promisors); the previous value of promisors is free()'d; then the new value of promisors (which is equal to the previous value of promisors) is also free()'d. This double-free error was unrecoverable for the user without removing the filter or re-cloning the repo and hoping to miss this edge case. Now, when promisor_remote_move_to_tail() would be a no-op, just do a no-op. In cases of promisor_remote_move_to_tail() where r is not already at the tail of the list, it works as before. Helped-by: Jeff King <peff@peff.net> Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Acked-by: Christian Couder <christian.couder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
268 lines
5.6 KiB
C
268 lines
5.6 KiB
C
#include "cache.h"
|
|
#include "object-store.h"
|
|
#include "promisor-remote.h"
|
|
#include "config.h"
|
|
#include "transport.h"
|
|
|
|
static char *repository_format_partial_clone;
|
|
static const char *core_partial_clone_filter_default;
|
|
|
|
void set_repository_format_partial_clone(char *partial_clone)
|
|
{
|
|
repository_format_partial_clone = xstrdup_or_null(partial_clone);
|
|
}
|
|
|
|
static int fetch_refs(const char *remote_name, struct ref *ref)
|
|
{
|
|
struct remote *remote;
|
|
struct transport *transport;
|
|
int original_fetch_if_missing = fetch_if_missing;
|
|
int res;
|
|
|
|
fetch_if_missing = 0;
|
|
remote = remote_get(remote_name);
|
|
if (!remote->url[0])
|
|
die(_("Remote with no URL"));
|
|
transport = transport_get(remote, remote->url[0]);
|
|
|
|
transport_set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
|
|
transport_set_option(transport, TRANS_OPT_NO_DEPENDENTS, "1");
|
|
res = transport_fetch_refs(transport, ref);
|
|
fetch_if_missing = original_fetch_if_missing;
|
|
|
|
return res;
|
|
}
|
|
|
|
static int fetch_objects(const char *remote_name,
|
|
const struct object_id *oids,
|
|
int oid_nr)
|
|
{
|
|
struct ref *ref = NULL;
|
|
int i;
|
|
|
|
for (i = 0; i < oid_nr; i++) {
|
|
struct ref *new_ref = alloc_ref(oid_to_hex(&oids[i]));
|
|
oidcpy(&new_ref->old_oid, &oids[i]);
|
|
new_ref->exact_oid = 1;
|
|
new_ref->next = ref;
|
|
ref = new_ref;
|
|
}
|
|
return fetch_refs(remote_name, ref);
|
|
}
|
|
|
|
static struct promisor_remote *promisors;
|
|
static struct promisor_remote **promisors_tail = &promisors;
|
|
|
|
static struct promisor_remote *promisor_remote_new(const char *remote_name)
|
|
{
|
|
struct promisor_remote *r;
|
|
|
|
if (*remote_name == '/') {
|
|
warning(_("promisor remote name cannot begin with '/': %s"),
|
|
remote_name);
|
|
return NULL;
|
|
}
|
|
|
|
FLEX_ALLOC_STR(r, name, remote_name);
|
|
|
|
*promisors_tail = r;
|
|
promisors_tail = &r->next;
|
|
|
|
return r;
|
|
}
|
|
|
|
static struct promisor_remote *promisor_remote_lookup(const char *remote_name,
|
|
struct promisor_remote **previous)
|
|
{
|
|
struct promisor_remote *r, *p;
|
|
|
|
for (p = NULL, r = promisors; r; p = r, r = r->next)
|
|
if (!strcmp(r->name, remote_name)) {
|
|
if (previous)
|
|
*previous = p;
|
|
return r;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void promisor_remote_move_to_tail(struct promisor_remote *r,
|
|
struct promisor_remote *previous)
|
|
{
|
|
if (r->next == NULL)
|
|
return;
|
|
|
|
if (previous)
|
|
previous->next = r->next;
|
|
else
|
|
promisors = r->next ? r->next : r;
|
|
r->next = NULL;
|
|
*promisors_tail = r;
|
|
promisors_tail = &r->next;
|
|
}
|
|
|
|
static int promisor_remote_config(const char *var, const char *value, void *data)
|
|
{
|
|
const char *name;
|
|
int namelen;
|
|
const char *subkey;
|
|
|
|
if (!strcmp(var, "core.partialclonefilter"))
|
|
return git_config_string(&core_partial_clone_filter_default,
|
|
var, value);
|
|
|
|
if (parse_config_key(var, "remote", &name, &namelen, &subkey) < 0)
|
|
return 0;
|
|
|
|
if (!strcmp(subkey, "promisor")) {
|
|
char *remote_name;
|
|
|
|
if (!git_config_bool(var, value))
|
|
return 0;
|
|
|
|
remote_name = xmemdupz(name, namelen);
|
|
|
|
if (!promisor_remote_lookup(remote_name, NULL))
|
|
promisor_remote_new(remote_name);
|
|
|
|
free(remote_name);
|
|
return 0;
|
|
}
|
|
if (!strcmp(subkey, "partialclonefilter")) {
|
|
struct promisor_remote *r;
|
|
char *remote_name = xmemdupz(name, namelen);
|
|
|
|
r = promisor_remote_lookup(remote_name, NULL);
|
|
if (!r)
|
|
r = promisor_remote_new(remote_name);
|
|
|
|
free(remote_name);
|
|
|
|
if (!r)
|
|
return 0;
|
|
|
|
return git_config_string(&r->partial_clone_filter, var, value);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int initialized;
|
|
|
|
static void promisor_remote_init(void)
|
|
{
|
|
if (initialized)
|
|
return;
|
|
initialized = 1;
|
|
|
|
git_config(promisor_remote_config, NULL);
|
|
|
|
if (repository_format_partial_clone) {
|
|
struct promisor_remote *o, *previous;
|
|
|
|
o = promisor_remote_lookup(repository_format_partial_clone,
|
|
&previous);
|
|
if (o)
|
|
promisor_remote_move_to_tail(o, previous);
|
|
else
|
|
promisor_remote_new(repository_format_partial_clone);
|
|
}
|
|
}
|
|
|
|
static void promisor_remote_clear(void)
|
|
{
|
|
while (promisors) {
|
|
struct promisor_remote *r = promisors;
|
|
promisors = promisors->next;
|
|
free(r);
|
|
}
|
|
|
|
promisors_tail = &promisors;
|
|
}
|
|
|
|
void promisor_remote_reinit(void)
|
|
{
|
|
initialized = 0;
|
|
promisor_remote_clear();
|
|
promisor_remote_init();
|
|
}
|
|
|
|
struct promisor_remote *promisor_remote_find(const char *remote_name)
|
|
{
|
|
promisor_remote_init();
|
|
|
|
if (!remote_name)
|
|
return promisors;
|
|
|
|
return promisor_remote_lookup(remote_name, NULL);
|
|
}
|
|
|
|
int has_promisor_remote(void)
|
|
{
|
|
return !!promisor_remote_find(NULL);
|
|
}
|
|
|
|
static int remove_fetched_oids(struct repository *repo,
|
|
struct object_id **oids,
|
|
int oid_nr, int to_free)
|
|
{
|
|
int i, remaining_nr = 0;
|
|
int *remaining = xcalloc(oid_nr, sizeof(*remaining));
|
|
struct object_id *old_oids = *oids;
|
|
struct object_id *new_oids;
|
|
|
|
for (i = 0; i < oid_nr; i++)
|
|
if (oid_object_info_extended(repo, &old_oids[i], NULL,
|
|
OBJECT_INFO_SKIP_FETCH_OBJECT)) {
|
|
remaining[i] = 1;
|
|
remaining_nr++;
|
|
}
|
|
|
|
if (remaining_nr) {
|
|
int j = 0;
|
|
new_oids = xcalloc(remaining_nr, sizeof(*new_oids));
|
|
for (i = 0; i < oid_nr; i++)
|
|
if (remaining[i])
|
|
oidcpy(&new_oids[j++], &old_oids[i]);
|
|
*oids = new_oids;
|
|
if (to_free)
|
|
free(old_oids);
|
|
}
|
|
|
|
free(remaining);
|
|
|
|
return remaining_nr;
|
|
}
|
|
|
|
int promisor_remote_get_direct(struct repository *repo,
|
|
const struct object_id *oids,
|
|
int oid_nr)
|
|
{
|
|
struct promisor_remote *r;
|
|
struct object_id *remaining_oids = (struct object_id *)oids;
|
|
int remaining_nr = oid_nr;
|
|
int to_free = 0;
|
|
int res = -1;
|
|
|
|
promisor_remote_init();
|
|
|
|
for (r = promisors; r; r = r->next) {
|
|
if (fetch_objects(r->name, remaining_oids, remaining_nr) < 0) {
|
|
if (remaining_nr == 1)
|
|
continue;
|
|
remaining_nr = remove_fetched_oids(repo, &remaining_oids,
|
|
remaining_nr, to_free);
|
|
if (remaining_nr) {
|
|
to_free = 1;
|
|
continue;
|
|
}
|
|
}
|
|
res = 0;
|
|
break;
|
|
}
|
|
|
|
if (to_free)
|
|
free(remaining_oids);
|
|
|
|
return res;
|
|
}
|