2011-05-26  Yaakov Selkowitz  <yselkowitz@...>

	* libc/include/string.h (strdupa): New macro function.
	(strndupa): New macro function.

Index: libc/include/string.h
===================================================================
RCS file: /cvs/src/src/newlib/libc/include/string.h,v
retrieving revision 1.27
diff -u -p -r1.27 string.h
--- libc/include/string.h	28 Mar 2011 14:51:28 -0000	1.27
+++ libc/include/string.h	26 May 2011 09:50:40 -0000
@@ -96,6 +96,20 @@ char  *_EXFUN(strsignal, (int __signo));
 int     _EXFUN(strtosigno, (const char *__name));
 #endif
 
+#if defined _GNU_SOURCE && defined __GNUC__
+#define strdupa(s) \
+	(__extension__ ({const char *__in = (s); \
+			 size_t __len = strlen (__in) + 1; \
+			 char * __out = (char *) __builtin_alloca (__len); \
+			 (char *) memcpy (__out, __in, __len);}))
+#define strndupa(s, n) \
+	(__extension__ ({const char *__in = (s); \
+			 size_t __len = strnlen (__in, (n)) + 1; \
+			 char *__out = (char *) __builtin_alloca (__len); \
+			 __out[__len-1] = '\0'; \
+			 (char *) memcpy (__out, __in, __len-1);}))
+#endif /* _GNU_SOURCE && __GNUC__ */
+
 /* These function names are used on Windows and perhaps other systems.  */
 #ifndef strcmpi
 #define strcmpi strcasecmp