commit de6d3e05678e68b1c919dd93a6aae6cc67fed51f
Author: Hasso Tepper <hasso@estpak.ee>
Date:   Wed Jan 7 09:43:23 2009 +0200

    Make the code using cmsgcred structure really work.
    
    Fixes dbus on FreeBSD and DragonFly systems. Also fix a compiler warning
    while in here:
    dbus-sysdeps-unix.c:1142: warning: ISO C90 forbids mixed declarations and code
    
    The patch is obtained from FreeBSD ports tree.

diff --git a/dbus/dbus-sysdeps-unix.c b/dbus/dbus-sysdeps-unix.c
index 29d234a..4ef8437 100644
--- a/dbus/dbus-sysdeps-unix.c
+++ b/dbus/dbus-sysdeps-unix.c
@@ -1047,9 +1047,9 @@ write_credentials_byte (int             server_fd,
   int bytes_written;
   char buf[1] = { '\0' };
 #if defined(HAVE_CMSGCRED) 
-  struct {
+  union {
 	  struct cmsghdr hdr;
-	  struct cmsgcred cred;
+	  char cred[CMSG_SPACE (sizeof (struct cmsgcred))];
   } cmsg;
   struct iovec iov;
   struct msghdr msg;
@@ -1060,10 +1060,10 @@ write_credentials_byte (int             server_fd,
   msg.msg_iov = &iov;
   msg.msg_iovlen = 1;
 
-  msg.msg_control = &cmsg;
-  msg.msg_controllen = sizeof (cmsg);
+  msg.msg_control = (caddr_t) &cmsg;
+  msg.msg_controllen = CMSG_SPACE (sizeof (struct cmsgcred));
   memset (&cmsg, 0, sizeof (cmsg));
-  cmsg.hdr.cmsg_len = sizeof (cmsg);
+  cmsg.hdr.cmsg_len = CMSG_LEN (sizeof (struct cmsgcred));
   cmsg.hdr.cmsg_level = SOL_SOCKET;
   cmsg.hdr.cmsg_type = SCM_CREDS;
 #endif
@@ -1135,13 +1135,10 @@ _dbus_read_credentials_socket  (int              client_fd,
   dbus_pid_t pid_read;
   int bytes_read;
   
-  uid_read = DBUS_UID_UNSET;
-  pid_read = DBUS_PID_UNSET;
-  
 #ifdef HAVE_CMSGCRED 
-  struct {
+  union {
     struct cmsghdr hdr;
-    struct cmsgcred cred;
+    char cred[CMSG_SPACE (sizeof (struct cmsgcred))];
   } cmsg;
 
 #elif defined(LOCAL_CREDS)
@@ -1151,6 +1148,9 @@ _dbus_read_credentials_socket  (int              client_fd,
   } cmsg;
 #endif
 
+  uid_read = DBUS_UID_UNSET;
+  pid_read = DBUS_PID_UNSET;
+
   _DBUS_ASSERT_ERROR_IS_CLEAR (error);
   
   /* The POSIX spec certainly doesn't promise this, but
@@ -1178,8 +1178,8 @@ _dbus_read_credentials_socket  (int              client_fd,
 
 #if defined(HAVE_CMSGCRED) || defined(LOCAL_CREDS)
   memset (&cmsg, 0, sizeof (cmsg));
-  msg.msg_control = &cmsg;
-  msg.msg_controllen = sizeof (cmsg);
+  msg.msg_control = (caddr_t) &cmsg;
+  msg.msg_controllen = CMSG_SPACE (sizeof (struct cmsgcred));
 #endif
 
  again:
@@ -1217,7 +1217,8 @@ _dbus_read_credentials_socket  (int              client_fd,
     }
 
 #if defined(HAVE_CMSGCRED) || defined(LOCAL_CREDS)
-  if (cmsg.hdr.cmsg_len < sizeof (cmsg) || cmsg.hdr.cmsg_type != SCM_CREDS)
+  if (cmsg.hdr.cmsg_len < CMSG_LEN (sizeof (struct cmsgcred))
+		  || cmsg.hdr.cmsg_type != SCM_CREDS)
     {
       dbus_set_error (error, DBUS_ERROR_FAILED,
                       "Message from recvmsg() was not SCM_CREDS");
@@ -1244,8 +1245,11 @@ _dbus_read_credentials_socket  (int              client_fd,
 		       cr_len, (int) sizeof (cr), _dbus_strerror (errno));
       }
 #elif defined(HAVE_CMSGCRED)
-    pid_read = cmsg.cred.cmcred_pid;
-    uid_read = cmsg.cred.cmcred_euid;
+    struct cmsgcred *cred;
+
+    cred = (struct cmsgcred *) CMSG_DATA (&cmsg);
+    pid_read = cred->cmcred_pid;
+    uid_read = cred->cmcred_euid;
 #elif defined(LOCAL_CREDS)
     pid_read = DBUS_PID_UNSET;
     uid_read = cmsg.cred.sc_uid;