net: Add NET_API to net/base

base/compiler_specific.h

Index: base/compiler_specific.h
===================================================================
--- base/compiler_specific.h	(revision 85332)
+++ base/compiler_specific.h	(working copy)
@@ -54,6 +54,19 @@
                                              code \
                                              MSVC_POP_WARNING()
 
+// Allows exporting a class that inherits from a non exported base class.

[wtc, 2011/05/16 23:07:13]

Nit: add '-' between 'non' and 'exported'.

+// This uses suppress instead of push/pop because the delimiter after the
+// declaration (either "," or "{") has to be placed before the pop macro.
+//
+// Example usage:
+// Class EXPORT_API Foo : NON_EXPORTED_BASE(public Bar) {
+//
+// Compiler warning C4275:

[wtc, 2011/05/16 23:07:13]

Nit: add "MSVC"

+// non dll-interface class 'Bar' used as base for dll-interface class 'Foo'
+// http://msdn.microsoft.com/en-us/library/3c594ae3(VS.80).aspx
+#define NON_EXPORTED_BASE(code) MSVC_SUPPRESS_WARNING(4275) \
+                                code
+
 #else  // Not MSVC
 
 #define MSVC_SUPPRESS_WARNING(n)
@@ -63,6 +76,7 @@
 #define MSVC_DISABLE_OPTIMIZE()
 #define MSVC_ENABLE_OPTIMIZE()
 #define ALLOW_THIS_IN_INITIALIZER_LIST(code) code
+#define NON_EXPORTED_BASE(code) code
 
 #endif  // COMPILER_MSVC