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, 2 insertions, 4 deletions

diff --git a/src/libsystemd/sd-bus/bus-container.c b/src/libsystemd/sd-bus/bus-container.c
index d330363b6f..2cd0e1f99e 100644
--- a/src/libsystemd/sd-bus/bus-container.c
+++ b/src/libsystemd/sd-bus/bus-container.c
@@ -154,8 +154,7 @@ int bus_container_connect_kernel(sd_bus *b) {
         if (child == 0) {
                 pid_t grandchild;
 
-                close_nointr_nofail(pair[0]);
-                pair[0] = -1;
+                pair[0] = safe_close(pair[0]);
 
                 r = namespace_enter(pidnsfd, mntnsfd, rootfd);
                 if (r < 0)
@@ -202,8 +201,7 @@ int bus_container_connect_kernel(sd_bus *b) {
                 _exit(si.si_status);
         }
 
-        close_nointr_nofail(pair[1]);
-        pair[1] = -1;
+        pair[1] = safe_close(pair[1]);
 
         r = wait_for_terminate(child, &si);
         if (r < 0)