merged new xmlrpc-c revision 1472 from https://xmlrpc-c.svn.sourceforge.net/svnroot/xmlrpc-c/trunk

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@8545 d0543943-73ff-0310-b7d9-9358b9ac24b2

libs/xmlrpc-c/lib/util/include/stdargx.h

@@ -0,0 +1,67 @@
+#ifndef STDARGX_H_INCLUDED
+#define STDARGX_H_INCLUDED
+
+#include "xmlrpc_config.h"
+#include <stdarg.h>
+#include <string.h>
+
+/*----------------------------------------------------------------------------
+   We need a special version of va_list in order to pass around the
+   variable argument heap by reference, thus allowing a subroutine to
+   advance the heap's pointer.
+
+   On some systems (e.g. Gcc for PPC or AMD64), va_list is an array.
+   That invites the scourge of array-to-pointer degeneration if you try
+   to take its address.  Burying it inside a struct as we do with out
+   va_listx type makes it immune.
+
+   Example of what would happen if we used va_list instead of va_listx,
+   on a system where va_list is an array:
+
+      void sub2(va_list * argsP) [
+          ...
+      }
+
+      void sub1(va_list args) {
+          sub2(&args);
+      }
+
+      This doesn't work.  '&args' is the same thing as 'args', so is
+      va_list, not va_list *.  The compiler will even warn you about the
+      pointer type mismatch.
+
+  To use va_listx:
+
+      void sub1_va(char * format, va_list args) {
+          va_listx argsx;
+          init_va_listx(&argsx, args);
+          sub2(format, &argsx);
+      }
+
+-----------------------------------------------------------------------------*/
+
+
+typedef struct {
+/*----------------------------------------------------------------------------
+   Same thing as va_list, but in a form that works everywhere.  See above.
+-----------------------------------------------------------------------------*/
+    va_list v;
+} va_listx;
+
+
+
+static __inline__ void
+init_va_listx(va_listx * const argsxP,
+              va_list    const args) {
+#if VA_LIST_IS_ARRAY
+    /* 'args' is NOT a va_list.  It is a pointer to the first element of a
+       'va_list', which is the same address as a pointer to the va_list
+       itself.
+    */
+    memcpy(&argsxP->v, args, sizeof(argsxP->v));
+#else
+    argsxP->v = args;
+#endif
+}
+
+#endif