--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2011-03-13  Bruno Haible  <bruno@clisp.org>
+
+	passfd module, part 2, tweaks.
+	* modules/passfd (Files): Reorder.
+	(Depends-on): Remove errno.
+	(Include): Remove <sys/socket.h>, <sys/un.h>.
+	* lib/passfd.h: Use a GPLv3+ header. Make C++ safe.
+	* lib/passfd.c: Untabify. Use a GPLv3+ header. Really include the
+	specification header. Include <sys/socket.h> always. Don't include
+	<winsock2.h>. Use "#if HAVE_..." instead of "#ifdef HAVE_...".
+	(sendfd): Clarify that it sets errno when it fails.
+	(recvfd): Fix specification.
+
 2011-03-07  Bastien Roucariès  <roucaries.bastien@gmail.com>
 
 	passfd module, part 2.

--- a/lib/passfd.c
+++ b/lib/passfd.c
@@ -2,7 +2,7 @@
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
+   the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
@@ -16,6 +16,8 @@
 #include <config.h>
 
 /* Specification.  */
+#include "passfd.h"
+
 #include <errno.h>
 #include <stddef.h>
 #include <stdlib.h>
@@ -23,20 +25,15 @@
 #include <sys/types.h>
 #include <unistd.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>
+#if HAVE_SYS_UN_H
+# include <sys/un.h>
 #endif
 
-/* Sendfd sends the file descriptor fd along the socket
+/* sendfd sends the file descriptor fd along the socket
    to a process calling recvfd on the other end.
-   
-   return -1 in case of error, 0 on success
+
+   Return 0 on success, or -1 with errno set in case of error.
 */
 int
 sendfd (int sock, int fd)
@@ -54,7 +51,7 @@
   msg.msg_namelen = 0;
 
   {
-#ifdef HAVE_UNIXSOCKET_SCM_RIGHTS_BSD44_WAY
+#if HAVE_UNIXSOCKET_SCM_RIGHTS_BSD44_WAY
     struct cmsghdr *cmsg;
     char buf[CMSG_SPACE (sizeof (fd))];
 
@@ -81,17 +78,14 @@
   return 0;
 }
 
-/* Sendfd sends the file descriptor fd along the socket 
-   to a process calling recvfd on the other end.
+/* recvfd receives a file descriptor through the socket.
 
-   return -1 in case of error, fd on success
+   Return 0 on success, or -1 with errno set in case of error.
 */
 int
 recvfd (int sock)
 {
   char recv = 0;
-  const int mone = -1;
-  int fd;
   struct iovec iov[1];
   struct msghdr msg;
 
@@ -104,9 +98,11 @@
   msg.msg_namelen = 0;
 
   {
-#ifdef HAVE_UNIXSOCKET_SCM_RIGHTS_BSD44_WAY
+#if HAVE_UNIXSOCKET_SCM_RIGHTS_BSD44_WAY
+    int fd;
     struct cmsghdr *cmsg;
     char buf[CMSG_SPACE (sizeof (fd))];
+    const int mone = -1;
 
     msg.msg_control = buf;
     msg.msg_controllen = sizeof (buf);
@@ -124,16 +120,18 @@
     cmsg = CMSG_FIRSTHDR (&msg);
     /* be paranoiac */
     if (cmsg == NULL || cmsg->cmsg_len != CMSG_LEN (sizeof (int))
-	|| cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS)
+        || cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS)
       {
-	/* fake errno: at end the file is not available */
-	errno = EACCES;
-	return -1;
+        /* fake errno: at end the file is not available */
+        errno = EACCES;
+        return -1;
       }
 
     memcpy (&fd, CMSG_DATA (cmsg), sizeof (fd));
     return fd;
 #elif HAVE_UNIXSOCKET_SCM_RIGHTS_BSD43_WAY
+    int fd;
+
     msg.msg_accrights = &fd;
     msg.msg_accrightslen = sizeof (fd);
     if (recvmsg (sock, &msg, 0) < 0)

--- a/lib/passfd.h
+++ b/lib/passfd.h
@@ -4,7 +4,7 @@
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
+   the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
@@ -14,8 +14,19 @@
 
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
 #ifndef PASSFD_H_
 #define PASSFD_H_ 1
-int sendfd (int sock, int fd);
-int recvfd (int sock);
+
+#ifdef __cplusplus
+extern "C" {
 #endif
+
+extern int sendfd (int sock, int fd);
+extern int recvfd (int sock);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

--- a/modules/passfd
+++ b/modules/passfd
@@ -2,13 +2,12 @@
 Passfile descriptors along Unix (socket/stream) file descriptors
 
 Files:
-m4/sockpfaf.m4
+lib/passfd.h
+lib/passfd.c
 m4/afunix.m4
-lib/passfd.c
-lib/passfd.h
+m4/sockpfaf.m4
 
 Depends-on:
-errno
 sys_socket
 extensions
 
@@ -19,8 +18,6 @@
 lib_SOURCES += passfd.c
 
 Include:
-<sys/socket.h>
-<sys/un.h>
 "passfd.h"
 
 License: