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.

1 files changed, 74 insertions, 0 deletions

diff --git a/inet/ifaddrs.h b/inet/ifaddrs.h
new file mode 100644
index 0000000000..ba6a1554b1
--- /dev/null
+++ b/inet/ifaddrs.h
@@ -0,0 +1,74 @@
+/* ifaddrs.h -- declarations for getting network interface addresses
+   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.  */
+
+#ifndef _IFADDRS_H
+#define _IFADDRS_H	1
+
+#include <features.h>
+#include <sys/socket.h>
+
+__BEGIN_DECLS
+
+/* The `getifaddrs' function generates a linked list of these structures.
+   Each element of the list describes one network interface.  */
+struct ifaddrs
+{
+  struct ifaddrs *ifa_next;	/* Pointer to the next structure.  */
+
+  char *ifa_name;		/* Name of this network interface.  */
+  unsigned int ifa_flags;	/* Flags as from SIOCGIFFLAGS ioctl.  */
+
+  struct sockaddr *ifa_addr;	/* Network address of this interface.  */
+  struct sockaddr *ifa_netmask; /* Netmask of this interface.  */
+  union
+  {
+    /* At most one of the following two is valid.  If the IFF_BROADCAST
+       bit is set in `ifa_flags', then `ifa_broadaddr' is valid.  If the
+       IFF_POINTOPOINT bit is set, then `ifa_dstaddr' is valid.
+       It is never the case that both these bits are set at once.  */
+    struct sockaddr *ifu_broadaddr; /* Broadcast address of this interface. */
+    struct sockaddr *ifu_dstaddr; /* Point-to-point destination address.  */
+  } ifa_ifu;
+  /* These very same macros are defined by <net/if.h> for `struct ifaddr'.
+     So if they are defined already, the existing definitions will be fine.  */
+# ifndef ifa_broadaddr
+#  define ifa_broadaddr	ifa_ifu.ifu_broadaddr
+# endif
+# ifndef ifa_dstaddr
+#  define ifa_dstaddr	ifa_ifu.ifu_dstaddr
+# endif
+
+  void *ifa_data;		/* Address-specific data (may be unused).  */
+};
+
+
+/* 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'.
+
+   The storage returned in *IFAP is allocated dynamically and can
+   only be properly freed by passing it to `freeifaddrs'.  */
+extern int getifaddrs (struct ifaddrs **__ifap) __THROW;
+
+/* Reclaim the storage allocated by a previous `getifaddrs' call.  */
+extern void freeifaddrs (struct ifaddrs *__ifa)  __THROW;
+
+__END_DECLS
+
+#endif /* ifaddrs.h */