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-rw-r--r--src/shared/lockfile-util.c154
1 files changed, 0 insertions, 154 deletions
diff --git a/src/shared/lockfile-util.c b/src/shared/lockfile-util.c
deleted file mode 100644
index 05e16d1caa..0000000000
--- a/src/shared/lockfile-util.c
+++ /dev/null
@@ -1,154 +0,0 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <stdlib.h>
-#include <stdbool.h>
-#include <errno.h>
-#include <string.h>
-#include <stdio.h>
-#include <limits.h>
-#include <sys/file.h>
-
-#include "util.h"
-#include "lockfile-util.h"
-#include "fileio.h"
-
-int make_lock_file(const char *p, int operation, LockFile *ret) {
- _cleanup_close_ int fd = -1;
- _cleanup_free_ char *t = NULL;
- int r;
-
- /*
- * We use UNPOSIX locks if they are available. They have nice
- * semantics, and are mostly compatible with NFS. However,
- * they are only available on new kernels. When we detect we
- * are running on an older kernel, then we fall back to good
- * old BSD locks. They also have nice semantics, but are
- * slightly problematic on NFS, where they are upgraded to
- * POSIX locks, even though locally they are orthogonal to
- * POSIX locks.
- */
-
- t = strdup(p);
- if (!t)
- return -ENOMEM;
-
- for (;;) {
- struct flock fl = {
- .l_type = (operation & ~LOCK_NB) == LOCK_EX ? F_WRLCK : F_RDLCK,
- .l_whence = SEEK_SET,
- };
- struct stat st;
-
- fd = open(p, O_CREAT|O_RDWR|O_NOFOLLOW|O_CLOEXEC|O_NOCTTY, 0600);
- if (fd < 0)
- return -errno;
-
- r = fcntl(fd, (operation & LOCK_NB) ? F_OFD_SETLK : F_OFD_SETLKW, &fl);
- if (r < 0) {
-
- /* If the kernel is too old, use good old BSD locks */
- if (errno == EINVAL)
- r = flock(fd, operation);
-
- if (r < 0)
- return errno == EAGAIN ? -EBUSY : -errno;
- }
-
- /* If we acquired the lock, let's check if the file
- * still exists in the file system. If not, then the
- * previous exclusive owner removed it and then closed
- * it. In such a case our acquired lock is worthless,
- * hence try again. */
-
- r = fstat(fd, &st);
- if (r < 0)
- return -errno;
- if (st.st_nlink > 0)
- break;
-
- fd = safe_close(fd);
- }
-
- ret->path = t;
- ret->fd = fd;
- ret->operation = operation;
-
- fd = -1;
- t = NULL;
-
- return r;
-}
-
-int make_lock_file_for(const char *p, int operation, LockFile *ret) {
- const char *fn;
- char *t;
-
- assert(p);
- assert(ret);
-
- fn = basename(p);
- if (!filename_is_valid(fn))
- return -EINVAL;
-
- t = newa(char, strlen(p) + 2 + 4 + 1);
- stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn), ".lck");
-
- return make_lock_file(t, operation, ret);
-}
-
-void release_lock_file(LockFile *f) {
- int r;
-
- if (!f)
- return;
-
- if (f->path) {
-
- /* If we are the exclusive owner we can safely delete
- * the lock file itself. If we are not the exclusive
- * owner, we can try becoming it. */
-
- if (f->fd >= 0 &&
- (f->operation & ~LOCK_NB) == LOCK_SH) {
- static const struct flock fl = {
- .l_type = F_WRLCK,
- .l_whence = SEEK_SET,
- };
-
- r = fcntl(f->fd, F_OFD_SETLK, &fl);
- if (r < 0 && errno == EINVAL)
- r = flock(f->fd, LOCK_EX|LOCK_NB);
-
- if (r >= 0)
- f->operation = LOCK_EX|LOCK_NB;
- }
-
- if ((f->operation & ~LOCK_NB) == LOCK_EX)
- unlink_noerrno(f->path);
-
- free(f->path);
- f->path = NULL;
- }
-
- f->fd = safe_close(f->fd);
- f->operation = 0;
-}