util: replace close_nointr_nofail() by a more useful safe_close()

safe_close() automatically becomes a NOP when a negative fd is passed,
and returns -1 unconditionally. This makes it easy to write lines like
this:

        fd = safe_close(fd);

Which will close an fd if it is open, and reset the fd variable
correctly.

By making use of this new scheme we can drop a > 200 lines of code that
was required to test for non-negative fds or to reset the closed fd
variable afterwards.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/core/umount.c b/src/core/umount.c
index 2d166c1c92..d1258f0f08 100644
--- a/src/core/umount.c
+++ b/src/core/umount.c
@@ -329,14 +329,14 @@ static int dm_list_get(MountPoint **head) {
 }
 
 static int delete_loopback(const char *device) {
-        int fd, r;
+        _cleanup_close_ int fd = -1;
+        int r;
 
-        if ((fd = open(device, O_RDONLY|O_CLOEXEC)) < 0)
+        fd = open(device, O_RDONLY|O_CLOEXEC);
+        if (fd < 0)
                 return errno == ENOENT ? 0 : -errno;
 
         r = ioctl(fd, LOOP_CLR_FD, 0);
-        close_nointr_nofail(fd);
-
         if (r >= 0)
                 return 1;