passfd: standardize coding conventions

* m4/afunix.m4 (gl_SOCKET_AFUNIX): Drop check for something that
can be learned at compile time.
* lib/passfd.c (MSG_CMSG_CLOEXEC): Reduce number of in-function
ifdefs.
(passfd, recvfd): Follow gnulib code conventions.

Signed-off-by: Eric Blake <eblake@redhat.com>

diff --git a/ChangeLog b/ChangeLog
index 0b7596d72f5d3f66d8797ff8f37122e5b67eea0b..79e70fca2a5b792b06d4b02ae7bb5151ce1d1aa5 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2011-03-30  Eric Blake  <eblake@redhat.com>
 
+       passfd: standardize coding conventions
+       * m4/afunix.m4 (gl_SOCKET_AFUNIX): Drop check for something that
+       can be learned at compile time.
+       * lib/passfd.c (MSG_CMSG_CLOEXEC): Reduce number of in-function
+       ifdefs.
+       (passfd, recvfd): Follow gnulib code conventions.
+
        passfd: fix incorrect sendmsg arguments
        * lib/passfd.c (sendfd): Avoid uninitialized msg_flags field, and
        incorrect msg_controllen value.

diff --git a/lib/passfd.c b/lib/passfd.c
index 5bf400d3e03ef29313bf454c484261507f144e71..6784659414f1521dcefa5bb9ed78d714138d9a58 100644 (file)
--- a/lib/passfd.c
+++ b/lib/passfd.c
@@ -34,6 +34,10 @@
 
 #include "cloexec.h"
 
+#ifndef MSG_CMSG_CLOEXEC
+# define MSG_CMSG_CLOEXEC 0
+#endif
+
 /* sendfd sends the file descriptor fd along the socket
    to a process calling recvfd on the other end.
 
@@ -43,41 +47,41 @@ int
 sendfd (int sock, int fd)
 {
   char send = 0;
-  struct iovec iov[1];
+  struct iovec iov;
   struct msghdr msg;
 
   /* send at least one char */
   memset (&msg, 0, sizeof msg);
-  iov[0].iov_base = &send;
-  iov[0].iov_len = 1;
-  msg.msg_iov = iov;
+  iov.iov_base = &send;
+  iov.iov_len = 1;
+  msg.msg_iov = &iov;
   msg.msg_iovlen = 1;
-  msg.msg_name = 0;
+  msg.msg_name = NULL;
   msg.msg_namelen = 0;
 
   {
 #if HAVE_UNIXSOCKET_SCM_RIGHTS_BSD44_WAY
     struct cmsghdr *cmsg;
-    char buf[CMSG_SPACE (sizeof (fd))];
+    char buf[CMSG_SPACE (sizeof fd)];
 
     msg.msg_control = buf;
-    msg.msg_controllen = sizeof (buf);
+    msg.msg_controllen = sizeof buf;
     cmsg = CMSG_FIRSTHDR (&msg);
     cmsg->cmsg_level = SOL_SOCKET;
     cmsg->cmsg_type = SCM_RIGHTS;
-    cmsg->cmsg_len = CMSG_LEN (sizeof (int));
+    cmsg->cmsg_len = CMSG_LEN (sizeof fd);
     /* Initialize the payload: */
-    memcpy (CMSG_DATA (cmsg), &fd, sizeof (fd));
+    memcpy (CMSG_DATA (cmsg), &fd, sizeof fd);
 #elif HAVE_UNIXSOCKET_SCM_RIGHTS_BSD43_WAY
     msg.msg_accrights = &fd;
-    msg.msg_accrightslen = sizeof (fd);
+    msg.msg_accrightslen = sizeof fd;
 #else
     errno = ENOSYS;
     return -1;
 #endif
   }
 
-  if (sendmsg (sock, &msg, 0) != iov[0].iov_len)
+  if (sendmsg (sock, &msg, 0) != iov.iov_len)
     return -1;
   return 0;
 }
@@ -91,7 +95,7 @@ int
 recvfd (int sock, int flags)
 {
   char recv = 0;
-  struct iovec iov[1];
+  struct iovec iov;
   struct msghdr msg;
 
   if ((flags & ~O_CLOEXEC) != 0)
@@ -101,33 +105,29 @@ recvfd (int sock, int flags)
     }
 
   /* send at least one char */
-  iov[0].iov_base = &recv;
-  iov[0].iov_len = 1;
-  msg.msg_iov = iov;
+  iov.iov_base = &recv;
+  iov.iov_len = 1;
+  msg.msg_iov = &iov;
   msg.msg_iovlen = 1;
-  msg.msg_name = 0;
+  msg.msg_name = NULL;
   msg.msg_namelen = 0;
 
   {
 #if HAVE_UNIXSOCKET_SCM_RIGHTS_BSD44_WAY
     int fd;
     struct cmsghdr *cmsg;
-    char buf[CMSG_SPACE (sizeof (fd))];
+    char buf[CMSG_SPACE (sizeof fd)];
     const int mone = -1;
-# if HAVE_MSG_CMSG_CLOEXEC
-    int flags_recvmsg = (flags & O_CLOEXEC ? MSG_CMSG_CLOEXEC : 0);
-# else
-    int flags_recvmsg = 0;
-# endif
+    int flags_recvmsg = flags & O_CLOEXEC ? MSG_CMSG_CLOEXEC : 0;
 
     msg.msg_control = buf;
-    msg.msg_controllen = sizeof (buf);
+    msg.msg_controllen = sizeof buf;
     cmsg = CMSG_FIRSTHDR (&msg);
     cmsg->cmsg_level = SOL_SOCKET;
     cmsg->cmsg_type = SCM_RIGHTS;
-    cmsg->cmsg_len = CMSG_LEN (sizeof (int));
+    cmsg->cmsg_len = CMSG_LEN (sizeof mone);
     /* Initialize the payload: */
-    memcpy (CMSG_DATA (cmsg), &mone, sizeof (mone));
+    memcpy (CMSG_DATA (cmsg), &mone, sizeof mone);
     msg.msg_controllen = cmsg->cmsg_len;
 
     if (recvmsg (sock, &msg, flags_recvmsg) < 0)
@@ -135,7 +135,7 @@ recvfd (int sock, int flags)
 
     cmsg = CMSG_FIRSTHDR (&msg);
     /* be paranoiac */
-    if (cmsg == NULL || cmsg->cmsg_len != CMSG_LEN (sizeof (int))
+    if (cmsg == NULL || cmsg->cmsg_len != CMSG_LEN (sizeof fd)
         || cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS)
       {
         /* fake errno: at end the file is not available */
@@ -143,11 +143,10 @@ recvfd (int sock, int flags)
         return -1;
       }
 
-    memcpy (&fd, CMSG_DATA (cmsg), sizeof (fd));
+    memcpy (&fd, CMSG_DATA (cmsg), sizeof fd);
 
-# if !HAVE_MSG_CMSG_CLOEXEC
     /* set close-on-exec flag */
-    if (flags & O_CLOEXEC)
+    if (!MSG_CMSG_CLOEXEC && (flags & O_CLOEXEC))
       {
         if (set_cloexec_flag (fd, true) < 0)
           {
@@ -157,7 +156,6 @@ recvfd (int sock, int flags)
             return -1;
           }
       }
-# endif
 
     return fd;
 
@@ -165,7 +163,7 @@ recvfd (int sock, int flags)
     int fd;
 
     msg.msg_accrights = &fd;
-    msg.msg_accrightslen = sizeof (fd);
+    msg.msg_accrightslen = sizeof fd;
     if (recvmsg (sock, &msg, 0) < 0)
       return -1;
 
@@ -175,7 +173,7 @@ recvfd (int sock, int flags)
         if (set_cloexec_flag (fd, true) < 0)
           {
             int saved_errno = errno;
-            (void) close (fd);
+            close (fd);
             errno = saved_errno;
             return -1;
           }

diff --git a/m4/afunix.m4 b/m4/afunix.m4
index 46b3bf34430b686612741d2d5e2bb16947c2e273..13f758316db6aaa88841cbfc67936f5451823446 100644 (file)
--- a/m4/afunix.m4
+++ b/m4/afunix.m4
@@ -1,4 +1,4 @@
-# afunix.m4 serial 5
+# afunix.m4 serial 6
 dnl Copyright (C) 2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -113,31 +113,4 @@ AC_DEFUN([gl_SOCKET_AFUNIX],
     AC_DEFINE([HAVE_UNIXSOCKET_SCM_RIGHTS_BSD43_WAY], [1],
       [Define to 1 if fd can be sent/received in the BSD4.3 way.])
   fi
-
-  AC_MSG_CHECKING([for UNIX domain sockets recvmsg() MSG_CMSG_CLOEXEC flag])
-  AC_CACHE_VAL([gl_cv_socket_unix_msg_cmsg_cloexec],
-    [AC_COMPILE_IFELSE(
-       [AC_LANG_PROGRAM(
-          [[#include <sys/types.h>
-            #ifdef HAVE_SYS_SOCKET_H
-            #include <sys/socket.h>
-            #endif
-            #ifdef HAVE_SYS_UN_H
-            #include <sys/un.h>
-            #endif
-            #ifdef HAVE_WINSOCK2_H
-            #include <winsock2.h>
-            #endif
-            ]],
-            [[int flags = MSG_CMSG_CLOEXEC;
-              if (&flags) return 0;
-            ]])],
-       [gl_cv_socket_unix_msg_cmsg_cloexec=yes],
-       [gl_cv_socket_unix_msg_cmsg_cloexec=no])
-    ])
-  AC_MSG_RESULT([$gl_cv_socket_unix_msg_cmsg_cloexec])
-  if test $gl_cv_socket_unix_msg_cmsg_cloexec = yes; then
-    AC_DEFINE([HAVE_MSG_CMSG_CLOEXEC], [1],
-      [Define to 1 if recvmsg could be specified with MSG_CMSG_CLOEXEC.])
-  fi
 ])