зеркало из https://github.com/microsoft/git.git
Merge branch 'mh/write-refs-sooner-2.4'
Multi-ref transaction support we merged a few releases ago unnecessarily kept many file descriptors open, risking to fail with resource exhaustion. This is for 2.4.x track. * mh/write-refs-sooner-2.4: ref_transaction_commit(): fix atomicity and avoid fd exhaustion ref_transaction_commit(): remove the local flags variable ref_transaction_commit(): inline call to write_ref_sha1() rename_ref(): inline calls to write_ref_sha1() from this function commit_ref_update(): new function, extracted from write_ref_sha1() write_ref_to_lockfile(): new function, extracted from write_ref_sha1() t7004: rename ULIMIT test prerequisite to ULIMIT_STACK_SIZE update-ref: test handling large transactions properly ref_transaction_commit(): fix atomicity and avoid fd exhaustion ref_transaction_commit(): remove the local flags variable ref_transaction_commit(): inline call to write_ref_sha1() rename_ref(): inline calls to write_ref_sha1() from this function commit_ref_update(): new function, extracted from write_ref_sha1() write_ref_to_lockfile(): new function, extracted from write_ref_sha1() t7004: rename ULIMIT test prerequisite to ULIMIT_STACK_SIZE update-ref: test handling large transactions properly
This commit is contained in:
Junio C Hamano
Коммит
91c90876de
113
refs.c
113
refs.c
|
|
@ -56,6 +56,12 @@ static unsigned char refname_disposition[256] = {
|
|||
*/
|
||||
#define REF_HAVE_OLD 0x10
|
||||
|
||||
/*
|
||||
* Used as a flag in ref_update::flags when the lockfile needs to be
|
||||
* committed.
|
||||
*/
|
||||
#define REF_NEEDS_COMMIT 0x20
|
||||
|
||||
/*
|
||||
* Try to read one refname component from the front of refname.
|
||||
* Return the length of the component found, or -1 if the component is
|
||||
|
|
@ -2788,8 +2794,9 @@ static int rename_ref_available(const char *oldname, const char *newname)
|
|||
return ret;
|
||||
}
|
||||
|
||||
static int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1,
|
||||
const char *logmsg);
|
||||
static int write_ref_to_lockfile(struct ref_lock *lock, const unsigned char *sha1);
|
||||
static int commit_ref_update(struct ref_lock *lock,
|
||||
const unsigned char *sha1, const char *logmsg);
|
||||
|
||||
int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
|
||||
{
|
||||
|
|
@ -2847,7 +2854,9 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
|
|||
goto rollback;
|
||||
}
|
||||
hashcpy(lock->old_sha1, orig_sha1);
|
||||
if (write_ref_sha1(lock, orig_sha1, logmsg)) {
|
||||
|
||||
if (write_ref_to_lockfile(lock, orig_sha1) ||
|
||||
commit_ref_update(lock, orig_sha1, logmsg)) {
|
||||
error("unable to write current sha1 into %s", newrefname);
|
||||
goto rollback;
|
||||
}
|
||||
|
|
@ -2863,7 +2872,8 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
|
|||
|
||||
flag = log_all_ref_updates;
|
||||
log_all_ref_updates = 0;
|
||||
if (write_ref_sha1(lock, orig_sha1, NULL))
|
||||
if (write_ref_to_lockfile(lock, orig_sha1) ||
|
||||
commit_ref_update(lock, orig_sha1, NULL))
|
||||
error("unable to write current sha1 into %s", oldrefname);
|
||||
log_all_ref_updates = flag;
|
||||
|
||||
|
|
@ -3052,11 +3062,11 @@ int is_branch(const char *refname)
|
|||
}
|
||||
|
||||
/*
|
||||
* Write sha1 into the ref specified by the lock. Make sure that errno
|
||||
* is sane on error.
|
||||
* Write sha1 into the open lockfile, then close the lockfile. On
|
||||
* errors, rollback the lockfile and set errno to reflect the problem.
|
||||
*/
|
||||
static int write_ref_sha1(struct ref_lock *lock,
|
||||
const unsigned char *sha1, const char *logmsg)
|
||||
static int write_ref_to_lockfile(struct ref_lock *lock,
|
||||
const unsigned char *sha1)
|
||||
{
|
||||
static char term = '\n';
|
||||
struct object *o;
|
||||
|
|
@ -3085,6 +3095,17 @@ static int write_ref_sha1(struct ref_lock *lock,
|
|||
errno = save_errno;
|
||||
return -1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Commit a change to a loose reference that has already been written
|
||||
* to the loose reference lockfile. Also update the reflogs if
|
||||
* necessary, using the specified lockmsg (which can be NULL).
|
||||
*/
|
||||
static int commit_ref_update(struct ref_lock *lock,
|
||||
const unsigned char *sha1, const char *logmsg)
|
||||
{
|
||||
clear_loose_ref_cache(&ref_cache);
|
||||
if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
|
||||
(strcmp(lock->ref_name, lock->orig_ref_name) &&
|
||||
|
|
@ -3775,19 +3796,24 @@ int ref_transaction_commit(struct ref_transaction *transaction,
|
|||
goto cleanup;
|
||||
}
|
||||
|
||||
/* Acquire all locks while verifying old values */
|
||||
/*
|
||||
* Acquire all locks, verify old values if provided, check
|
||||
* that new values are valid, and write new values to the
|
||||
* lockfiles, ready to be activated. Only keep one lockfile
|
||||
* open at a time to avoid running out of file descriptors.
|
||||
*/
|
||||
for (i = 0; i < n; i++) {
|
||||
struct ref_update *update = updates[i];
|
||||
unsigned int flags = update->flags;
|
||||
|
||||
if ((flags & REF_HAVE_NEW) && is_null_sha1(update->new_sha1))
|
||||
flags |= REF_DELETING;
|
||||
if ((update->flags & REF_HAVE_NEW) &&
|
||||
is_null_sha1(update->new_sha1))
|
||||
update->flags |= REF_DELETING;
|
||||
update->lock = lock_ref_sha1_basic(
|
||||
update->refname,
|
||||
((update->flags & REF_HAVE_OLD) ?
|
||||
update->old_sha1 : NULL),
|
||||
NULL,
|
||||
flags,
|
||||
update->flags,
|
||||
&update->type);
|
||||
if (!update->lock) {
|
||||
ret = (errno == ENOTDIR)
|
||||
|
|
@ -3797,34 +3823,60 @@ int ref_transaction_commit(struct ref_transaction *transaction,
|
|||
update->refname);
|
||||
goto cleanup;
|
||||
}
|
||||
}
|
||||
|
||||
/* Perform updates first so live commits remain referenced */
|
||||
for (i = 0; i < n; i++) {
|
||||
struct ref_update *update = updates[i];
|
||||
int flags = update->flags;
|
||||
|
||||
if ((flags & REF_HAVE_NEW) && !is_null_sha1(update->new_sha1)) {
|
||||
if ((update->flags & REF_HAVE_NEW) &&
|
||||
!(update->flags & REF_DELETING)) {
|
||||
int overwriting_symref = ((update->type & REF_ISSYMREF) &&
|
||||
(update->flags & REF_NODEREF));
|
||||
|
||||
if (!overwriting_symref
|
||||
&& !hashcmp(update->lock->old_sha1, update->new_sha1)) {
|
||||
if (!overwriting_symref &&
|
||||
!hashcmp(update->lock->old_sha1, update->new_sha1)) {
|
||||
/*
|
||||
* The reference already has the desired
|
||||
* value, so we don't need to write it.
|
||||
*/
|
||||
unlock_ref(update->lock);
|
||||
} else if (write_ref_to_lockfile(update->lock,
|
||||
update->new_sha1)) {
|
||||
/*
|
||||
* The lock was freed upon failure of
|
||||
* write_ref_to_lockfile():
|
||||
*/
|
||||
update->lock = NULL;
|
||||
} else if (write_ref_sha1(update->lock, update->new_sha1,
|
||||
update->msg)) {
|
||||
update->lock = NULL; /* freed by write_ref_sha1 */
|
||||
strbuf_addf(err, "Cannot update the ref '%s'.",
|
||||
update->refname);
|
||||
ret = TRANSACTION_GENERIC_ERROR;
|
||||
goto cleanup;
|
||||
} else {
|
||||
/* freed by write_ref_sha1(): */
|
||||
update->flags |= REF_NEEDS_COMMIT;
|
||||
}
|
||||
}
|
||||
if (!(update->flags & REF_NEEDS_COMMIT)) {
|
||||
/*
|
||||
* We didn't have to write anything to the lockfile.
|
||||
* Close it to free up the file descriptor:
|
||||
*/
|
||||
if (close_ref(update->lock)) {
|
||||
strbuf_addf(err, "Couldn't close %s.lock",
|
||||
update->refname);
|
||||
goto cleanup;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* Perform updates first so live commits remain referenced */
|
||||
for (i = 0; i < n; i++) {
|
||||
struct ref_update *update = updates[i];
|
||||
|
||||
if (update->flags & REF_NEEDS_COMMIT) {
|
||||
if (commit_ref_update(update->lock,
|
||||
update->new_sha1, update->msg)) {
|
||||
/* freed by commit_ref_update(): */
|
||||
update->lock = NULL;
|
||||
strbuf_addf(err, "Cannot update the ref '%s'.",
|
||||
update->refname);
|
||||
ret = TRANSACTION_GENERIC_ERROR;
|
||||
goto cleanup;
|
||||
} else {
|
||||
/* freed by commit_ref_update(): */
|
||||
update->lock = NULL;
|
||||
}
|
||||
}
|
||||
|
|
@ -3833,15 +3885,14 @@ int ref_transaction_commit(struct ref_transaction *transaction,
|
|||
/* Perform deletes now that updates are safely completed */
|
||||
for (i = 0; i < n; i++) {
|
||||
struct ref_update *update = updates[i];
|
||||
int flags = update->flags;
|
||||
|
||||
if ((flags & REF_HAVE_NEW) && is_null_sha1(update->new_sha1)) {
|
||||
if (update->flags & REF_DELETING) {
|
||||
if (delete_ref_loose(update->lock, update->type, err)) {
|
||||
ret = TRANSACTION_GENERIC_ERROR;
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
if (!(flags & REF_ISPRUNING))
|
||||
if (!(update->flags & REF_ISPRUNING))
|
||||
string_list_append(&refs_to_delete,
|
||||
update->lock->ref_name);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -1065,4 +1065,32 @@ test_expect_success 'stdin -z delete refs works with packed and loose refs' '
|
|||
test_must_fail git rev-parse --verify -q $c
|
||||
'
|
||||
|
||||
run_with_limited_open_files () {
|
||||
(ulimit -n 32 && "$@")
|
||||
}
|
||||
|
||||
test_lazy_prereq ULIMIT_FILE_DESCRIPTORS 'run_with_limited_open_files true'
|
||||
|
||||
test_expect_success ULIMIT_FILE_DESCRIPTORS 'large transaction creating branches does not burst open file limit' '
|
||||
(
|
||||
for i in $(test_seq 33)
|
||||
do
|
||||
echo "create refs/heads/$i HEAD"
|
||||
done >large_input &&
|
||||
run_with_limited_open_files git update-ref --stdin <large_input &&
|
||||
git rev-parse --verify -q refs/heads/33
|
||||
)
|
||||
'
|
||||
|
||||
test_expect_success ULIMIT_FILE_DESCRIPTORS 'large transaction deleting branches does not burst open file limit' '
|
||||
(
|
||||
for i in $(test_seq 33)
|
||||
do
|
||||
echo "delete refs/heads/$i HEAD"
|
||||
done >large_input &&
|
||||
run_with_limited_open_files git update-ref --stdin <large_input &&
|
||||
test_must_fail git rev-parse --verify -q refs/heads/33
|
||||
)
|
||||
'
|
||||
|
||||
test_done
|
||||
|
|
|
|||
|
|
@ -1491,10 +1491,10 @@ run_with_limited_stack () {
|
|||
(ulimit -s 128 && "$@")
|
||||
}
|
||||
|
||||
test_lazy_prereq ULIMIT 'run_with_limited_stack true'
|
||||
test_lazy_prereq ULIMIT_STACK_SIZE 'run_with_limited_stack true'
|
||||
|
||||
# we require ulimit, this excludes Windows
|
||||
test_expect_success ULIMIT '--contains works in a deep repo' '
|
||||
test_expect_success ULIMIT_STACK_SIZE '--contains works in a deep repo' '
|
||||
>expect &&
|
||||
i=1 &&
|
||||
while test $i -lt 8000
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче