glapi: Generate GL API marshalling code from the XML.

This is not yet used in the build, just generated.

v2: Add missing build dependencies.
v3: Avoid mixing declarations and code, remove logic for avoiding emitting
    code that the compiler's optimizer can deal with anyway.
v4: (Timothy Arceri) move safe_mul() genereation here from a later patch.

Acked-by: Timothy Arceri <tarceri@itsqueeze.com>
Acked-by: Marek Olšák <maraeo@gmail.com>
Tested-by: Dieter Nützel <Dieter@nuetzel-hh.de>
Tested-by: Mike Lothian <mike@fireburn.co.uk>

src/mesa/SConscript

@@ -118,6 +118,22 @@ if env['platform'] not in ('cygwin', 'darwin', 'windows', 'haiku'):
         env.Prepend(CPPPATH = [matypes[0].dir])
 
 
+# The marshal_generated.c file is generated from the GL/ES API.xml file
+env.CodeGenerate(
+    target = 'main/marshal_generated.c',
+    script = GLAPI + 'gen/gl_marshal.py',
+    source = GLAPI + 'gen/gl_and_es_API.xml',
+    command = python_cmd + ' $SCRIPT -f $SOURCE > $TARGET'
+    )
+
+# The marshal_generated.h file is generated from the GL/ES API.xml file
+env.CodeGenerate(
+    target = 'main/marshal_generated.h',
+    script = GLAPI + 'gen/gl_marshal_h.py',
+    source = GLAPI + 'gen/gl_and_es_API.xml',
+    command = python_cmd + ' $SCRIPT -f $SOURCE > $TARGET'
+    )
+
 #
 # Libraries
 #