Fix getifaddrs, freeifaddrs namespace (bug 17668)

[Joseph Myers <joseph at codesourcery dot com>]

Various objects in glibc bring in ifaddrs.o (via references to
__netlink_*) and thereby getifaddrs and freeifaddrs, which are not
part of any standard supported by glibc.  These should be weak aliases
of __getifaddrs and __freeifaddrs; this patch makes them so.

(The path by which these functions are brought in is Linux-specific,
but it seems less confusing to make all versions of these functions
weak aliases rather than only the Linux-specific versions that
definitely need it.)

Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by this patch).

2014-12-02  Joseph Myers  <joseph@codesourcery.com>

	[BZ #17668]
	* inet/ifaddrs.c (getifaddrs): Rename to __getifaddrs and define
	as weak alias of __getifaddrs.  Use libc_hidden_weak.
	(freeifaddrs): Rename to __freeifaddrs and define as weak alias of
	__freeifaddrs.  Use libc_hidden_weak.
	* sysdeps/gnu/ifaddrs.c (getifaddrs): Rename to __getifaddrs and
	define as weak alias of __getifaddrs.  Use libc_hidden_weak.
	(freeifaddrs): Rename to __freeifaddrs and define as weak alias of
	__freeifaddrs.  Use libc_hidden_weak.
	* sysdeps/unix/sysv/linux/ifaddrs.c (getifaddrs): Rename to
	__getifaddrs and define as weak alias of __getifaddrs.  Use
	libc_hidden_weak.
	(freeifaddrs): Rename to __freeifaddrs and define as weak alias of
	__freeifaddrs.  Use libc_hidden_weak.
	* conform/Makefile (test-xfail-XOPEN2K/net/if.h/linknamespace):
	Remove variable.
	(test-xfail-POSIX2008/net/if.h/linknamespace): Likewise.
	(test-xfail-XOPEN2K8/net/if.h/linknamespace): Likewise.

diff --git a/conform/Makefile b/conform/Makefile
index 641f546..0c3d3ca 100644
--- a/conform/Makefile
+++ b/conform/Makefile
@@ -418,7 +418,6 @@ test-xfail-XOPEN2K/glob.h/linknamespace = yes
 test-xfail-XOPEN2K/grp.h/linknamespace = yes
 test-xfail-XOPEN2K/libgen.h/linknamespace = yes
 test-xfail-XOPEN2K/mqueue.h/linknamespace = yes
-test-xfail-XOPEN2K/net/if.h/linknamespace = yes
 test-xfail-XOPEN2K/netdb.h/linknamespace = yes
 test-xfail-XOPEN2K/pthread.h/linknamespace = yes
 test-xfail-XOPEN2K/pwd.h/linknamespace = yes
@@ -442,7 +441,6 @@ test-xfail-POSIX2008/dirent.h/linknamespace = yes
 test-xfail-POSIX2008/fcntl.h/linknamespace = yes
 test-xfail-POSIX2008/grp.h/linknamespace = yes
 test-xfail-POSIX2008/mqueue.h/linknamespace = yes
-test-xfail-POSIX2008/net/if.h/linknamespace = yes
 test-xfail-POSIX2008/netdb.h/linknamespace = yes
 test-xfail-POSIX2008/pthread.h/linknamespace = yes
 test-xfail-POSIX2008/regex.h/linknamespace = yes
@@ -459,7 +457,6 @@ test-xfail-XOPEN2K8/fmtmsg.h/linknamespace = yes
 test-xfail-XOPEN2K8/grp.h/linknamespace = yes
 test-xfail-XOPEN2K8/libgen.h/linknamespace = yes
 test-xfail-XOPEN2K8/mqueue.h/linknamespace = yes
-test-xfail-XOPEN2K8/net/if.h/linknamespace = yes
 test-xfail-XOPEN2K8/netdb.h/linknamespace = yes
 test-xfail-XOPEN2K8/pthread.h/linknamespace = yes
 test-xfail-XOPEN2K8/pwd.h/linknamespace = yes
diff --git a/inet/ifaddrs.c b/inet/ifaddrs.c
index 8071600..bc273c6 100644
--- a/inet/ifaddrs.c
+++ b/inet/ifaddrs.c
@@ -24,16 +24,17 @@
    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)
+__getifaddrs (struct ifaddrs **ifap)
 {
   __set_errno (ENOSYS);
   return -1;
 }
-libc_hidden_def (getifaddrs)
+weak_alias (__getifaddrs, getifaddrs)
+libc_hidden_weak (getifaddrs)
 stub_warning (getifaddrs)
 
 void
-freeifaddrs (struct ifaddrs *ifa)
+__freeifaddrs (struct ifaddrs *ifa)
 {
   if (ifa == NULL)
     return;			/* a la free, why not? */
@@ -41,5 +42,6 @@ freeifaddrs (struct ifaddrs *ifa)
   /* Can't be called properly if getifaddrs never succeeded.  */
   abort ();
 }
-libc_hidden_def (freeifaddrs)
+weak_alias (__freeifaddrs, freeifaddrs)
+libc_hidden_weak (freeifaddrs)
 stub_warning (freeifaddrs)
diff --git a/sysdeps/gnu/ifaddrs.c b/sysdeps/gnu/ifaddrs.c
index 1b8775f..3607b2c 100644
--- a/sysdeps/gnu/ifaddrs.c
+++ b/sysdeps/gnu/ifaddrs.c
@@ -32,7 +32,7 @@
    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)
+__getifaddrs (struct ifaddrs **ifap)
 {
   /* This implementation handles only IPv4 interfaces.
      The various ioctls below will only work on an AF_INET socket.
@@ -150,13 +150,15 @@ getifaddrs (struct ifaddrs **ifap)
 
   return 0;
 }
+weak_alias (__getifaddrs, getifaddrs)
 #ifndef getifaddrs
-libc_hidden_def (getifaddrs)
+libc_hidden_weak (getifaddrs)
 #endif
 
 void
-freeifaddrs (struct ifaddrs *ifa)
+__freeifaddrs (struct ifaddrs *ifa)
 {
   free (ifa);
 }
-libc_hidden_def (freeifaddrs)
+weak_alias (__freeifaddrs, freeifaddrs)
+libc_hidden_weak (freeifaddrs)
diff --git a/sysdeps/unix/sysv/linux/ifaddrs.c b/sysdeps/unix/sysv/linux/ifaddrs.c
index a47b2ed..3f03f86 100644
--- a/sysdeps/unix/sysv/linux/ifaddrs.c
+++ b/sysdeps/unix/sysv/linux/ifaddrs.c
@@ -819,7 +819,7 @@ getifaddrs_internal (struct ifaddrs **ifap)
    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)
+__getifaddrs (struct ifaddrs **ifap)
 {
   int res;
 
@@ -829,12 +829,14 @@ getifaddrs (struct ifaddrs **ifap)
 
   return res;
 }
-libc_hidden_def (getifaddrs)
+weak_alias (__getifaddrs, getifaddrs)
+libc_hidden_weak (getifaddrs)
 
 
 void
-freeifaddrs (struct ifaddrs *ifa)
+__freeifaddrs (struct ifaddrs *ifa)
 {
   free (ifa);
 }
-libc_hidden_def (freeifaddrs)
+weak_alias (__freeifaddrs, freeifaddrs)
+libc_hidden_weak (freeifaddrs)

-- 
Joseph S. Myers
joseph@codesourcery.com