util: ignore kernel errors reported via close(), unless it is EBADF

The kernel can return pretty much anything there, even though the fd is
closed. Let's not get confused by that.

diff --git a/src/shared/util.c b/src/shared/util.c
index 1a727ca40a6d0da07859ffbf067dec2727018b2b..c8a017db862713223c33a779a6fe869d1e2ddaba 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -166,19 +166,19 @@ int close_nointr(int fd) {
 
         assert(fd >= 0);
         r = close(fd);
-
-        /* Just ignore EINTR; a retry loop is the wrong
-         * thing to do on Linux.
-         *
-         * http://lkml.indiana.edu/hypermail/linux/kernel/0509.1/0877.html
-         * https://bugzilla.gnome.org/show_bug.cgi?id=682819
-         * http://utcc.utoronto.ca/~cks/space/blog/unix/CloseEINTR
-         * https://sites.google.com/site/michaelsafyan/software-engineering/checkforeintrwheninvokingclosethinkagain
-         */
-        if (_unlikely_(r < 0 && errno == EINTR))
-                return 0;
-        else if (r >= 0)
+        if (r >= 0)
                 return r;
+        else if (errno == EINTR)
+                /*
+                 * Just ignore EINTR; a retry loop is the wrong
+                 * thing to do on Linux.
+                 *
+                 * http://lkml.indiana.edu/hypermail/linux/kernel/0509.1/0877.html
+                 * https://bugzilla.gnome.org/show_bug.cgi?id=682819
+                 * http://utcc.utoronto.ca/~cks/space/blog/unix/CloseEINTR
+                 * https://sites.google.com/site/michaelsafyan/software-engineering/checkforeintrwheninvokingclosethinkagain
+                 */
+                return 0;
         else
                 return -errno;
 }
@@ -195,7 +195,13 @@ int safe_close(int fd) {
 
         if (fd >= 0) {
                 PROTECT_ERRNO;
-                assert_se(close_nointr(fd) == 0);
+
+                /* The kernel might return pretty much any error code
+                 * via close(), but the fd will be closed anyway. The
+                 * only condition we want to check for here is whether
+                 * the fd was invalid at all... */
+
+                assert_se(close_nointr(fd) != -EBADF);
         }
 
         return -1;