From ad738d03aeee1a5d780a1875b02f2a7c0afa8291 Mon Sep 17 00:00:00 2001
From: Miles Bader <miles@gnu.org>
Date: Sun, 30 Jul 1995 00:37:36 +0000
Subject: [PATCH] (accept): If the protocol family can't tell us what an
 address means, just   return a zero-length buffer instead.

---
 sysdeps/mach/hurd/accept.c   | 15 +++++++++++++--
 sysdeps/mach/hurd/recvfrom.c | 11 ++++++++++-
 sysdeps/mach/hurd/sendto.c   | 32 +++++++++++++++++++++++++++-----
 3 files changed, 50 insertions(+), 8 deletions(-)

diff --git a/sysdeps/mach/hurd/accept.c b/sysdeps/mach/hurd/accept.c
index 48402b1227..528d4252fd 100644
--- a/sysdeps/mach/hurd/accept.c
+++ b/sysdeps/mach/hurd/accept.c
@@ -45,7 +45,17 @@ DEFUN(accept, (fd, addr, addr_len),
     return __hurd_dfail (fd, err);
 
   if (addr != NULL)
-    err = __socket_whatis_address (aport, &type, &buf, &buflen);
+    {
+      err = __socket_whatis_address (aport, &type, &buf, &buflen);
+      if (err == EOPNOTSUPP)
+	/* If the protocol server can't tell us the address, just return a
+	   zero-length one.  */
+	{
+	  buf = (char *)addr;
+	  buflen = 0;
+	  err = 0;
+	}
+    }
   __mach_port_deallocate (__mach_task_self (), aport);
 
   if (err)
@@ -64,7 +74,8 @@ DEFUN(accept, (fd, addr, addr_len),
 	  __vm_deallocate (__mach_task_self (), (vm_address_t) buf, buflen);
 	}
 
-      addr->sa_family = type;
+      if (buflen > 0)
+	addr->sa_family = type;
     }
 
   return _hurd_intern_fd (new, O_IGNORE_CTTY, 1);
diff --git a/sysdeps/mach/hurd/recvfrom.c b/sysdeps/mach/hurd/recvfrom.c
index 09d45c7cc8..4a69af41ce 100644
--- a/sysdeps/mach/hurd/recvfrom.c
+++ b/sysdeps/mach/hurd/recvfrom.c
@@ -56,6 +56,14 @@ DEFUN(recvfrom, (fd, buf, n, flags, addr, addr_len),
     int type;
 
     err = __socket_whatis_address (addrport, &type, &buf, &buflen);
+    if (err == EOPNOTSUPP)
+      /* If the protocol server can't tell us the address, just return a
+	 zero-length one.  */
+      {
+	buf = (char *)addr;
+	buflen = 0;
+	err = 0;
+      }
     __mach_port_deallocate (__mach_task_self (), addrport);
     if (err)
       return __hurd_dfail (fd, err);
@@ -68,7 +76,8 @@ DEFUN(recvfrom, (fd, buf, n, flags, addr, addr_len),
 	__vm_deallocate (__mach_task_self (), (vm_address_t) buf, buflen);
       }
 
-    addr->sa_family = type;
+    if (buflen > 0)
+      addr->sa_family = type;
   }
 
   /* Toss control data; we don't care.  */
diff --git a/sysdeps/mach/hurd/sendto.c b/sysdeps/mach/hurd/sendto.c
index c3d4a4e121..94becae0a4 100644
--- a/sysdeps/mach/hurd/sendto.c
+++ b/sysdeps/mach/hurd/sendto.c
@@ -22,6 +22,8 @@ Cambridge, MA 02139, USA.  */
 #include <hurd.h>
 #include <hurd/socket.h>
 #include <hurd/fd.h>
+#include <sys/un.h>
+#include <hurd/ifsock.h>
 
 /* Send N bytes of BUF on socket FD to peer at address ADDR (which is
    ADDR_LEN bytes long).  Returns the number sent, or -1 for errors.  */
@@ -33,15 +35,35 @@ DEFUN(sendto, (fd, buf, n, flags, addr, addr_len),
   addr_port_t aport;
   error_t err;
   int wrote;
+  
+  if (addr->sa_family == AF_LOCAL)
+    {
+      /* For the local domain, we must look up the name as a file and talk
+	 to it with the ifsock protocol.  */
+      struct sockaddr_un *unaddr = (struct sockaddr_un *) addr;
+      file_t file = __file_name_lookup (unaddr->sun_path, 0, 0);
+      if (file == MACH_PORT_NULL)
+	return -1;
+      err = __ifsock_getsockaddr (file, &aport);
+      __mach_port_deallocate (__mach_task_self (), file);
+      if (err == MIG_BAD_ID || err == EOPNOTSUPP)
+	/* The file did not grok the ifsock protocol.  */
+	err = ENOTSOCK;
+      if (err)
+	return __hurd_fail (err);
+    }
+  else
+    err = EIEIO;
 
   /* Get an address port for the desired destination address.  */
   err = HURD_DPORT_USE (fd,
 			({
-			  err = __socket_create_address (port,
-							 addr->sa_family,
-							 (char *) addr,
-							 addr_len,
-							 &aport, 1);
+			  if (err)
+			    err = __socket_create_address (port,
+							   addr->sa_family,
+							   (char *) addr,
+							   addr_len,
+							   &aport, 1);
 			  if (! err)
 			    {
 			      /* Send the data.  */
-- 
2.11.4.GIT