From ee4d8e455c0981269213eccfd788a9bb9adf77d9 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Tue, 5 Sep 2017 08:15:15 -0400 Subject: [PATCH] ref_lock: stop leaking lock_files Since the tempfile code recently relaxed the rule that tempfile structs (and thus locks) need to hang around forever, we no longer have to leak our lock_file structs. In fact, we don't even need to heap-allocate them anymore, since their lifetime can just match that of the surrounding ref_lock (and if we forget to delete a lock, the effect is the same as before: it will eventually go away at program exit). Note that there is a check in unlock_ref() to only rollback a lock file if it has been allocated. We don't need that check anymore; we zero the ref_lock (and thus the lock_file), so at worst we pass a NULL pointer to delete_tempfile(), which considers that a noop. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- refs/files-backend.c | 39 ++++++++++++++++----------------------- 1 file changed, 16 insertions(+), 23 deletions(-) diff --git a/refs/files-backend.c b/refs/files-backend.c index 36fe8a986b..f3455609d6 100644 --- a/refs/files-backend.c +++ b/refs/files-backend.c @@ -12,7 +12,7 @@ struct ref_lock { char *ref_name; - struct lock_file *lk; + struct lock_file lk; struct object_id old_oid; }; @@ -418,9 +418,7 @@ out: static void unlock_ref(struct ref_lock *lock) { - /* Do not free lock->lk -- atexit() still looks at them */ - if (lock->lk) - rollback_lock_file(lock->lk); + rollback_lock_file(&lock->lk); free(lock->ref_name); free(lock); } @@ -534,11 +532,8 @@ retry: goto error_return; } - if (!lock->lk) - lock->lk = xcalloc(1, sizeof(struct lock_file)); - if (hold_lock_file_for_update_timeout( - lock->lk, ref_file.buf, LOCK_NO_DEREF, + &lock->lk, ref_file.buf, LOCK_NO_DEREF, get_files_ref_lock_timeout_ms()) < 0) { if (errno == ENOENT && --attempts_remaining > 0) { /* @@ -949,11 +944,9 @@ static struct ref_lock *lock_ref_sha1_basic(struct files_ref_store *refs, goto error_return; } - lock->lk = xcalloc(1, sizeof(struct lock_file)); - lock->ref_name = xstrdup(refname); - if (raceproof_create_file(ref_file.buf, create_reflock, lock->lk)) { + if (raceproof_create_file(ref_file.buf, create_reflock, &lock->lk)) { last_errno = errno; unable_to_lock_message(ref_file.buf, errno, err); goto error_return; @@ -1404,14 +1397,14 @@ static int files_rename_ref(struct ref_store *ref_store, static int close_ref_gently(struct ref_lock *lock) { - if (close_lock_file_gently(lock->lk)) + if (close_lock_file_gently(&lock->lk)) return -1; return 0; } static int commit_ref(struct ref_lock *lock) { - char *path = get_locked_file_path(lock->lk); + char *path = get_locked_file_path(&lock->lk); struct stat st; if (!lstat(path, &st) && S_ISDIR(st.st_mode)) { @@ -1435,7 +1428,7 @@ static int commit_ref(struct ref_lock *lock) free(path); } - if (commit_lock_file(lock->lk)) + if (commit_lock_file(&lock->lk)) return -1; return 0; } @@ -1627,12 +1620,12 @@ static int write_ref_to_lockfile(struct ref_lock *lock, unlock_ref(lock); return -1; } - fd = get_lock_file_fd(lock->lk); + fd = get_lock_file_fd(&lock->lk); if (write_in_full(fd, oid_to_hex(oid), GIT_SHA1_HEXSZ) != GIT_SHA1_HEXSZ || write_in_full(fd, &term, 1) != 1 || close_ref_gently(lock) < 0) { strbuf_addf(err, - "couldn't write '%s'", get_lock_file_path(lock->lk)); + "couldn't write '%s'", get_lock_file_path(&lock->lk)); unlock_ref(lock); return -1; } @@ -1709,7 +1702,7 @@ static int create_ref_symlink(struct ref_lock *lock, const char *target) { int ret = -1; #ifndef NO_SYMLINK_HEAD - char *ref_path = get_locked_file_path(lock->lk); + char *ref_path = get_locked_file_path(&lock->lk); unlink(ref_path); ret = symlink(target, ref_path); free(ref_path); @@ -1745,14 +1738,14 @@ static int create_symref_locked(struct files_ref_store *refs, return 0; } - if (!fdopen_lock_file(lock->lk, "w")) + if (!fdopen_lock_file(&lock->lk, "w")) return error("unable to fdopen %s: %s", - lock->lk->tempfile->filename.buf, strerror(errno)); + lock->lk.tempfile->filename.buf, strerror(errno)); update_symref_reflog(refs, lock, refname, target, logmsg); /* no error check; commit_ref will check ferror */ - fprintf(lock->lk->tempfile->fp, "ref: %s\n", target); + fprintf(lock->lk.tempfile->fp, "ref: %s\n", target); if (commit_ref(lock) < 0) return error("unable to write symref for %s: %s", refname, strerror(errno)); @@ -2853,12 +2846,12 @@ static int files_reflog_expire(struct ref_store *ref_store, strerror(errno)); rollback_lock_file(&reflog_lock); } else if (update && - (write_in_full(get_lock_file_fd(lock->lk), + (write_in_full(get_lock_file_fd(&lock->lk), oid_to_hex(&cb.last_kept_oid), GIT_SHA1_HEXSZ) != GIT_SHA1_HEXSZ || - write_str_in_full(get_lock_file_fd(lock->lk), "\n") != 1 || + write_str_in_full(get_lock_file_fd(&lock->lk), "\n") != 1 || close_ref_gently(lock) < 0)) { status |= error("couldn't write %s", - get_lock_file_path(lock->lk)); + get_lock_file_path(&lock->lk)); rollback_lock_file(&reflog_lock); } else if (commit_lock_file(&reflog_lock)) { status |= error("unable to write reflog '%s' (%s)",