Added <ifaddrs.h> interface with functions `getifaddrs', `freeifaddrs'.

	This implementation supports only IPv4.
	* inet/ifaddrs.h: New file.
	* sysdeps/generic/ifaddrs.c: New file.
	* sysdeps/gnu/ifaddrs.c: New file.
	* inet/test-ifaddrs.c: New file.
	* inet/Makefile (routines): Add ifaddrs.
	(headers): Add ifaddrs.h here.
	(tests): Add test-ifaddrs.
	* inet/Versions (GLIBC_2.3): New set, add getifaddrs and freeifaddrs.

	* resolv/res_hconf.c (_res_hconf_reorder_addrs): Use an explicit
	socket call to get an AF_INET socket, instead of using __opensock.
	The SIOCGIFNETMASK ioctl will work only with a PF_INET socket.

	* sysdeps/generic/ifreq.h (__ifreq): Take third argument SOCKFD,
	if not -1 use it instead of calling __opensock.
	* sysdeps/unix/sysv/linux/ifreq.h (__ifreq): Likewise.
	* sysdeps/mach/hurd/ifreq.h (__ifreq): Take new argument and ignore it.
	* resolv/res_hconf.c (_res_hconf_reorder_addrs): Pass new argument.

	* sysdeps/mach/hurd/ifreq.h: New file.
	* sysdeps/generic/ifreq.h (__if_freereq): Take second argument NUM_IFS.
	* sysdeps/unix/sysv/linux/ifreq.h (__if_freereq): Likewise.
	* resolv/res_hconf.c (_res_hconf_reorder_addrs): Update caller.

2 files changed, 55 insertions, 7 deletions

diff --git a/sysdeps/generic/ifaddrs.c b/sysdeps/generic/ifaddrs.c
new file mode 100644
index 0000000000..7b29aa111c
--- /dev/null
+++ b/sysdeps/generic/ifaddrs.c
@@ -0,0 +1,44 @@
+/* getifaddrs -- get names and addresses of all network interfaces
+   Copyright (C) 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <ifaddrs.h>
+#include <errno.h>
+#include <stdlib.h>
+
+/* Create a linked list of `struct ifaddrs' structures, one for each
+   network interface on the host machine.  If successful, store the
+   list in *IFAP and return 0.  On errors, return -1 and set `errno'.  */
+int
+getifaddrs (struct ifaddrs **ifap)
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+stub_warning (getifaddrs)
+
+void
+freeifaddrs (struct ifaddrs *ifa)
+{
+  if (ifa == NULL)
+    return;			/* a la free, why not? */
+
+  /* Can't be called properly if getifaddrs never succeeded.  */
+  abort ();
+}
+stub_warning (freeifaddrs)
diff --git a/sysdeps/generic/ifreq.h b/sysdeps/generic/ifreq.h
index 62f3dcfaf9..c96d1c8789 100644
--- a/sysdeps/generic/ifreq.h
+++ b/sysdeps/generic/ifreq.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1999 Free Software Foundation, Inc.
+/* Copyright (C) 1999,2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Andreas Jaeger <aj@suse.de>.
 
@@ -26,15 +26,17 @@
 
 
 static inline void
-__ifreq (struct ifreq **ifreqs, int *num_ifs)
+__ifreq (struct ifreq **ifreqs, int *num_ifs, int sockfd)
 {
-  int fd = __opensock ();
+  int fd = sockfd;
   struct ifconf ifc;
   int rq_len;
   int nifs;
 # define RQ_IFS	4
 
   if (fd < 0)
+    fd = __opensock ();
+  if (fd < 0)
     {
       *num_ifs = 0;
       *ifreqs = NULL;
@@ -51,8 +53,9 @@ __ifreq (struct ifreq **ifreqs, int *num_ifs)
 	{
 	  if (ifc.ifc_buf)
 	    free (ifc.ifc_buf);
-	  
-	  __close (fd);
+
+	  if (fd != sockfd)
+	    __close (fd);
 	  *num_ifs = 0;
 	  *ifreqs = NULL;
 	  return;
@@ -63,7 +66,8 @@ __ifreq (struct ifreq **ifreqs, int *num_ifs)
 
   nifs = ifc.ifc_len / sizeof (struct ifreq);
 
-  __close (fd);
+  if (fd != sockfd)
+    __close (fd);
 
   *num_ifs = nifs;
   *ifreqs = realloc (ifc.ifc_buf, nifs * sizeof (struct ifreq));
@@ -71,7 +75,7 @@ __ifreq (struct ifreq **ifreqs, int *num_ifs)
 
 
 static inline void
-__if_freereq (struct ifreq *ifreqs)
+__if_freereq (struct ifreq *ifreqs, int num_ifs)
 {
   free (ifreqs);
 }