MdePkg: Add a new macro VA_COPY for variable argument support. Fix a bug in the UefiLib instance that there is a non portable assumption that Marker is copied when passed to a function.

Signed-off-by: rsun3
Reviewed-by: mdkinney


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13025 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 19 insertions, 1 deletions

diff --git a/MdePkg/Include/Base.h b/MdePkg/Include/Base.h
index 4fcc3a1bf6..66fc5d271b 100644
--- a/MdePkg/Include/Base.h
+++ b/MdePkg/Include/Base.h
@@ -6,7 +6,7 @@
   environment. There are a set of base libraries in the Mde Package that can

   be used to implement base modules.

 

-Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>

+Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>

 Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>

 This program and the accompanying materials

 are licensed and made available under the terms and conditions of the BSD License

@@ -393,6 +393,7 @@ struct _LIST_ENTRY {
 //  VA_END (VA_LIST Marker) - Clear Marker

 //  VA_ARG (VA_LIST Marker, var arg size) - Use Marker to get an argument from

 //    the ... list. You must know the size and pass it in this macro.

+//  VA_COPY (VA_LIST Dest, VA_LIST Start) - Initialize Dest as a copy of Start.

 //

 //  example:

 //

@@ -454,6 +455,8 @@ struct _LIST_ENTRY {
 

 #define VA_END(Marker)                ((void)0)

 

+#define VA_COPY(Dest, Start)          __va_copy (Dest, Start)

+

 #elif defined(__GNUC__) && !defined(NO_BUILTIN_VA_FUNCS)

 //

 // Use GCC built-in macros for variable argument lists.

@@ -471,6 +474,8 @@ typedef __builtin_va_list VA_LIST;
 

 #define VA_END(Marker)               __builtin_va_end (Marker)

 

+#define VA_COPY(Dest, Start)         __builtin_va_copy (Dest, Start)

+

 #else

 ///

 /// Variable used to traverse the list of arguments. This type can vary by

@@ -526,6 +531,19 @@ typedef CHAR8 *VA_LIST;
 **/

 #define VA_END(Marker)      (Marker = (VA_LIST) 0)

 

+/**

+  Initializes a VA_LIST as a copy of an existing VA_LIST.

+

+  This macro initializes Dest as a copy of Start, as if the VA_START macro had been applied to Dest

+  followed by the same sequence of uses of the VA_ARG macro as had previously been used to reach

+  the present state of Start. 

+

+  @param   Dest   VA_LIST used to traverse the list of arguments.

+  @param   Start  VA_LIST used to traverse the list of arguments.

+

+**/

+#define VA_COPY(Dest, Start)  ((void)((Dest) = (Start)))

+

 #endif

 

 ///