Add new attribute called static_dispatch to the <function> element. This

boolean attribute, which defaults to true, determines whether or not a
static dispatch function is available in libGL for applications to link
against.

Ideally, any new functions that are not part of the ABI should not have
directly accessable dispatch functions.  This forces applications to use
glXGetProcAddress to access these functions.  By doing this we can
gracefully remove functions from libGL without breaking the linkage of
applications.

Note that the static dispatch functions are still generated.  However, they
are given names like gl_dispatch_stub_820 and are marked with the "hidden"
linker attribute.

All extension functions added since the previous Mesa release (6.5) have
been marked as 'static_dispatch="false"'.

1 files changed, 34 insertions, 8 deletions

diff --git a/src/mesa/glapi/gl_apitemp.py b/src/mesa/glapi/gl_apitemp.py
index 7cc434fa89b..30ee6596ed3 100644
--- a/src/mesa/glapi/gl_apitemp.py
+++ b/src/mesa/glapi/gl_apitemp.py
@@ -39,6 +39,7 @@ class PrintGlOffsets(gl_XML.gl_print_base):
 (C) Copyright IBM Corporation 2004""", "BRIAN PAUL, IBM")
 
 		self.undef_list.append( "KEYWORD1" )
+		self.undef_list.append( "KEYWORD1_ALT" )
 		self.undef_list.append( "KEYWORD2" )
 		self.undef_list.append( "NAME" )
 		self.undef_list.append( "DISPATCH" )
@@ -54,6 +55,13 @@ class PrintGlOffsets(gl_XML.gl_print_base):
 		t_string = ""
 		comma = ""
 
+		if f.static_dispatch:
+			n = name
+			keyword = "KEYWORD1"
+		else:
+			n = "_dispatch_stub_%u" % (f.offset)
+			keyword = "KEYWORD1_ALT"
+
 		for p in f.parameterIterator():
 			if p.is_pointer():
 				cast = "(const void *) "
@@ -71,8 +79,11 @@ class PrintGlOffsets(gl_XML.gl_print_base):
 		else:
 			dispatch = "DISPATCH"
 
-		print 'KEYWORD1 %s KEYWORD2 NAME(%s)(%s)' \
-			% (f.return_type, name, f.get_parameter_string(name))
+		if not f.static_dispatch:
+			print '%s %s KEYWORD2 NAME(%s)(%s);' % (keyword, f.return_type, n, f.get_parameter_string(name))
+			print ''
+
+		print '%s %s KEYWORD2 NAME(%s)(%s)' % (keyword, f.return_type, n, f.get_parameter_string(name))
 		print '{'
 		if p_string == "":
 			print '   %s(%s, (), (F, "gl%s();\\n"));' \
@@ -85,6 +96,8 @@ class PrintGlOffsets(gl_XML.gl_print_base):
 		return
 
 	def printRealHeader(self):
+		print ''
+		self.printVisibility( "HIDDEN", "hidden" )
 		print """
 /*
  * This file is a template which generates the OpenGL API entry point
@@ -116,6 +129,10 @@ class PrintGlOffsets(gl_XML.gl_print_base):
 #define KEYWORD1
 #endif
 
+#ifndef KEYWORD1_ALT
+#define KEYWORD1_ALT HIDDEN
+#endif
+
 #ifndef KEYWORD2
 #define KEYWORD2
 #endif
@@ -149,7 +166,12 @@ class PrintGlOffsets(gl_XML.gl_print_base):
 
 static _glapi_proc DISPATCH_TABLE_NAME[] = {"""
 		for f in api.functionIterateByOffset():
-			print '   TABLE_ENTRY(%s),' % (f.name)
+			if f.static_dispatch:
+				n = f.name
+			else:
+				n = "_dispatch_stub_%u" % (f.offset)
+
+			print '   TABLE_ENTRY(%s),' % (n)
 
 		print '   /* A whole bunch of no-op functions.  These might be called'
 		print '    * when someone tries to call a dynamically-registered'
@@ -174,9 +196,10 @@ static _glapi_proc DISPATCH_TABLE_NAME[] = {"""
 static _glapi_proc UNUSED_TABLE_NAME[] = {"""
 
 		for f in api.functionIterateByOffset():
-			for n in f.entry_points:
-				if n != f.name:
-					print '   TABLE_ENTRY(%s),' % (n)
+			if f.static_dispatch:
+				for n in f.entry_points:
+					if n != f.name:
+						print '   TABLE_ENTRY(%s),' % (n)
 
 		print '};'
 		print '#endif /*UNUSED_TABLE_NAME*/'
@@ -186,8 +209,11 @@ static _glapi_proc UNUSED_TABLE_NAME[] = {"""
 
 	def printBody(self, api):
 		for func in api.functionIterateByOffset():
-			for n in func.entry_points:
-				self.printFunction( func, n )
+			if func.static_dispatch:
+				for n in func.entry_points:
+					self.printFunction( func, n )
+			else:
+				self.printFunction(func, func.name)
 
 		self.printInitDispatch(api)
 		self.printAliasedTable(api)