*_strerror_r.c: keep all occurences in sync with string.h

libc-internal.h: this has to provide the reversed case of what string.h defines.
Accomodate for later possibility to compile without _GNU_SOURCE defined

Signed-off-by: Peter S. Mazinger <ps.m@gmx.net>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

include/libc-internal.h

@@ -44,12 +44,12 @@
 #  include <stddef.h>
 
 /* sources are built w/ _GNU_SOURCE, this gets undefined */
-#ifdef __USE_GNU
-extern int __xpg_strerror_r (int __errnum, char *__buf, size_t __buflen);
-libc_hidden_proto(__xpg_strerror_r)
-#else
+#if defined __USE_XOPEN2K && !defined  __USE_GNU
 extern char *__glibc_strerror_r (int __errnum, char *__buf, size_t __buflen);
 libc_hidden_proto(__glibc_strerror_r)
+#else
+extern int __xpg_strerror_r (int __errnum, char *__buf, size_t __buflen);
+libc_hidden_proto(__xpg_strerror_r)
 #endif
 
 /* #include <pthread.h> */

libc/string/__glibc_strerror_r.c

@@ -5,9 +5,13 @@
  * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
  */
 
+/* get rid of REDIRECT */
+#define strerror_r __hide_strerror_r
+
 #include <features.h>
 #include <string.h>
 
+#undef strerror_r
 
 char *__glibc_strerror_r(int errnum, char *strerrbuf, size_t buflen)
 {
@@ -16,3 +20,6 @@ char *__glibc_strerror_r(int errnum, char *strerrbuf, size_t buflen)
     return strerrbuf;
 }
 libc_hidden_def(__glibc_strerror_r)
+#if !defined __USE_XOPEN2K || defined __USE_GNU
+strong_alias(__glibc_strerror_r,strerror_r)
+#endif

libc/string/__xpg_strerror_r.c

@@ -5,11 +5,16 @@
  * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
  */
 
+/* get rid of REDIRECT */
+#define strerror_r __hide_strerror_r
+
 #include <features.h>
 #include <errno.h>
 #include <string.h>
 #include "_syserrmsg.h"
 
+#undef strerror_r
+
 #ifdef __UCLIBC_HAS_ERRNO_MESSAGES__
 
 extern const char _string_syserrmsgs[] attribute_hidden;
@@ -267,4 +272,6 @@ int __xpg_strerror_r(int errnum, char *strerrbuf, size_t buflen)
 
 #endif /* __UCLIBC_HAS_ERRNO_MESSAGES__ */
 libc_hidden_def(__xpg_strerror_r)
-strong_alias_untyped(__xpg_strerror_r, strerror_r)
+#if defined __USE_XOPEN2K && !defined __USE_GNU
+strong_alias(__xpg_strerror_r,strerror_r)
+#endif