inet: Make IN6_IS_ADDR_UNSPECIFIED etc. usable with POSIX [BZ #16421]

Previously, under some feature test macros and compilers, the
macros were defined, but references undefined struct members
in their implementation.

2016-11-25  Carlos O'Donell  <carlos@redhat.com>
	    Florian Weimer  <fweimer@redhat.com>

	[BZ #16421]
	* inet/netinet/in.h (struct in6_addr): Always define __u6_addr16
	and __u6_addr32 members.
	(IN6_IS_ADDR_UNSPECIFIED, IN6_IS_ADDR_LOOPBACK)
	(IN6_IS_ADDR_LINKLOCAL, IN6_IS_ADDR_SITELOCAL)
	(IN6_IS_ADDR_V4MAPPED, IN6_IS_ADDR_V4COMPAT, IN6_ARE_ADDR_EQUAL):
	Use __u6_addr32.
	* inet/tst-checks-posix.c: New file.
	* inet/Makefile (tests): Add it.
	(CFLAGS-tst-checks-posix.c): Compile in C99 mode.
	* test-skeleton.c (xasprintf, struct temp_name_list)
	(temp_name_list, add_temp_file, delete_temp_files)
	(create_temp_file): Define only under _GNU_SOURCE.
	(usage): Add argv parameter.
	(main): Call usage with argv argument.  Register delete_temp_files
	and log temporary files only under _GNU_SOURCE.  Explicitly retry
	waitpid.

diff --git a/inet/Makefile b/inet/Makefile
index 1c30932..c82ad92 100644
--- a/inet/Makefile
+++ b/inet/Makefile
@@ -51,8 +51,8 @@ aux := check_pf check_native ifreq
 
 tests := htontest test_ifindex tst-ntoa tst-ether_aton tst-network \
 	 tst-gethnm test-ifaddrs bug-if1 test-inet6_opt tst-ether_line \
-	 tst-getni1 tst-getni2 tst-inet6_rth tst-checks tst-sockaddr \
-	 tst-inet6_scopeid_pton
+	 tst-getni1 tst-getni2 tst-inet6_rth tst-checks tst-checks-posix \
+	 tst-sockaddr tst-inet6_scopeid_pton
 
 include ../Rules
 
@@ -86,6 +86,7 @@ CFLAGS-either_hton.c = -fexceptions
 CFLAGS-getnetgrent.c = -fexceptions
 CFLAGS-getnetgrent_r.c = -fexceptions
 
+CFLAGS-tst-checks-posix.c = -std=c99
 CFLAGS-tst-sockaddr.c = -fno-strict-aliasing
 
 endif
diff --git a/inet/netinet/in.h b/inet/netinet/in.h
index c801593..01594c6 100644
--- a/inet/netinet/in.h
+++ b/inet/netinet/in.h
@@ -213,10 +213,8 @@ struct in6_addr
     union
       {
 	uint8_t	__u6_addr8[16];
-#ifdef __USE_MISC
 	uint16_t __u6_addr16[8];
 	uint32_t __u6_addr32[4];
-#endif
       } __in6_u;
 #define s6_addr			__in6_u.__u6_addr8
 #ifdef __USE_MISC
@@ -411,52 +409,52 @@ extern uint16_t htons (uint16_t __hostshort)
 # define IN6_IS_ADDR_UNSPECIFIED(a) \
   (__extension__							      \
    ({ const struct in6_addr *__a = (const struct in6_addr *) (a);	      \
-      __a->s6_addr32[0] == 0						      \
-      && __a->s6_addr32[1] == 0						      \
-      && __a->s6_addr32[2] == 0						      \
-      && __a->s6_addr32[3] == 0; }))
+      __a->__in6_u.__u6_addr32[0] == 0					      \
+      && __a->__in6_u.__u6_addr32[1] == 0				      \
+      && __a->__in6_u.__u6_addr32[2] == 0				      \
+      && __a->__in6_u.__u6_addr32[3] == 0; }))
 
 # define IN6_IS_ADDR_LOOPBACK(a) \
   (__extension__							      \
    ({ const struct in6_addr *__a = (const struct in6_addr *) (a);	      \
-      __a->s6_addr32[0] == 0						      \
-      && __a->s6_addr32[1] == 0						      \
-      && __a->s6_addr32[2] == 0						      \
-      && __a->s6_addr32[3] == htonl (1); }))
+      __a->__in6_u.__u6_addr32[0] == 0					      \
+      && __a->__in6_u.__u6_addr32[1] == 0				      \
+      && __a->__in6_u.__u6_addr32[2] == 0				      \
+      && __a->__in6_u.__u6_addr32[3] == htonl (1); }))
 
 # define IN6_IS_ADDR_LINKLOCAL(a) \
   (__extension__							      \
    ({ const struct in6_addr *__a = (const struct in6_addr *) (a);	      \
-      (__a->s6_addr32[0] & htonl (0xffc00000)) == htonl (0xfe800000); }))
+      (__a->__in6_u.__u6_addr32[0] & htonl (0xffc00000)) == htonl (0xfe800000); }))
 
 # define IN6_IS_ADDR_SITELOCAL(a) \
   (__extension__							      \
    ({ const struct in6_addr *__a = (const struct in6_addr *) (a);	      \
-      (__a->s6_addr32[0] & htonl (0xffc00000)) == htonl (0xfec00000); }))
+      (__a->__in6_u.__u6_addr32[0] & htonl (0xffc00000)) == htonl (0xfec00000); }))
 
 # define IN6_IS_ADDR_V4MAPPED(a) \
   (__extension__							      \
    ({ const struct in6_addr *__a = (const struct in6_addr *) (a);	      \
-      __a->s6_addr32[0] == 0						      \
-      && __a->s6_addr32[1] == 0						      \
-      && __a->s6_addr32[2] == htonl (0xffff); }))
+      __a->__in6_u.__u6_addr32[0] == 0					      \
+      && __a->__in6_u.__u6_addr32[1] == 0				      \
+      && __a->__in6_u.__u6_addr32[2] == htonl (0xffff); }))
 
 # define IN6_IS_ADDR_V4COMPAT(a) \
   (__extension__							      \
    ({ const struct in6_addr *__a = (const struct in6_addr *) (a);	      \
-      __a->s6_addr32[0] == 0						      \
-      && __a->s6_addr32[1] == 0						      \
-      && __a->s6_addr32[2] == 0						      \
-      && ntohl (__a->s6_addr32[3]) > 1; }))
+      __a->__in6_u.__u6_addr32[0] == 0					      \
+      && __a->__in6_u.__u6_addr32[1] == 0				      \
+      && __a->__in6_u.__u6_addr32[2] == 0				      \
+      && ntohl (__a->__in6_u.__u6_addr32[3]) > 1; }))
 
 # define IN6_ARE_ADDR_EQUAL(a,b) \
   (__extension__							      \
    ({ const struct in6_addr *__a = (const struct in6_addr *) (a);	      \
       const struct in6_addr *__b = (const struct in6_addr *) (b);	      \
-      __a->s6_addr32[0] == __b->s6_addr32[0]				      \
-      && __a->s6_addr32[1] == __b->s6_addr32[1]				      \
-      && __a->s6_addr32[2] == __b->s6_addr32[2]				      \
-      && __a->s6_addr32[3] == __b->s6_addr32[3]; }))
+      __a->__in6_u.__u6_addr32[0] == __b->__in6_u.__u6_addr32[0]	      \
+      && __a->__in6_u.__u6_addr32[1] == __b->__in6_u.__u6_addr32[1]	      \
+      && __a->__in6_u.__u6_addr32[2] == __b->__in6_u.__u6_addr32[2]	      \
+      && __a->__in6_u.__u6_addr32[3] == __b->__in6_u.__u6_addr32[3]; }))
 #else
 # define IN6_IS_ADDR_UNSPECIFIED(a) \
 	(((const uint32_t *) (a))[0] == 0				      \
diff --git a/inet/tst-checks-posix.c b/inet/tst-checks-posix.c
new file mode 100644
index 0000000..aab92ac
--- /dev/null
+++ b/inet/tst-checks-posix.c
@@ -0,0 +1,25 @@
+/* Test IPv6 classification macros in POSIX mode.
+   Copyright (C) 2016 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Process tst-checks.c in POSIX mode.  POSIX 2008 is required by the
+   test skeleton.  */
+#undef _GNU_SOURCE
+#define _POSIX_C_SOURCE 200809L
+#define _ISOMAC
+
+#include "tst-checks.c"
diff --git a/test-skeleton.c b/test-skeleton.c
index fa457be..dcb3e3a 100644
--- a/test-skeleton.c
+++ b/test-skeleton.c
@@ -149,6 +149,7 @@ xrealloc (void *p, size_t n)
   return result;
 }
 
+#ifdef __USE_GNU
 /* Call asprintf with error checking.  */
 __attribute__ ((always_inline, format (printf, 1, 2)))
 static __inline__ char *
@@ -162,6 +163,7 @@ xasprintf (const char *format, ...)
     }
   return result;
 }
+#endif /* __USE_GNU */
 
 /* Write a message to standard output.  Can be used in signal
    handlers.  */
@@ -173,6 +175,7 @@ write_message (const char *message)
   unused = write (STDOUT_FILENO, message, strlen (message));
 }
 
+#ifdef __USE_GNU
 /* List of temporary files.  */
 struct temp_name_list
 {
@@ -247,6 +250,7 @@ create_temp_file (const char *base, char **filename)
 
   return fd;
 }
+#endif/* __USE_GNU */
 
 /* Timeout handler.  We kill the child and exit with an error.  */
 static void
@@ -351,7 +355,7 @@ set_fortify_handler (void (*handler) (int sig))
 
 /* Show people how to run the program.  */
 static void
-usage (void)
+usage (char **argv)
 {
   size_t i;
 
@@ -361,7 +365,7 @@ usage (void)
 	  "  TIMEOUTFACTOR          An integer used to scale the timeout\n"
 	  "  TMPDIR                 Where to place temporary files\n"
 	  "\n",
-	  program_invocation_short_name);
+	  argv[0]);
   printf ("Options:\n");
   for (i = 0; options[i].name; ++i)
     {
@@ -407,7 +411,7 @@ main (int argc, char *argv[])
     switch (opt)
       {
       case '?':
-	usage ();
+	usage (argv);
 	exit (1);
       case OPT_DIRECT:
 	direct = 1;
@@ -454,8 +458,10 @@ main (int argc, char *argv[])
   /* Make sure we see all message, even those on stdout.  */
   setvbuf (stdout, NULL, _IONBF, 0);
 
+#ifdef __USE_GNU
   /* Make sure temporary files are deleted.  */
   atexit (delete_temp_files);
+#endif
 
   /* Correct for the possible parameters.  */
   argv[optind - 1] = argv[0];
@@ -493,6 +499,7 @@ main (int argc, char *argv[])
         }
 #endif
 
+#ifdef __USE_GNU
       if (temp_name_list != NULL)
         {
           struct temp_name_list *n;
@@ -503,6 +510,7 @@ main (int argc, char *argv[])
             fprintf (f, "  '%s'\n", n->name);
           fprintf (f, ")\n");
         }
+#endif /* __USE_GNU */
 
       fclose (f);
       direct = 1;
@@ -551,7 +559,9 @@ main (int argc, char *argv[])
   signal (SIGINT, signal_handler);
 
   /* Wait for the regular termination.  */
-  termpid = TEMP_FAILURE_RETRY (waitpid (pid, &status, 0));
+  do
+    termpid = waitpid (pid, &status, 0);
+  while (termpid == -1 && errno == EINTR);
   if (termpid == -1)
     {
       printf ("Waiting for test program failed: %m\n");
