glsl: Move functions into standalone_scaffolding.cpp for later reuse.

This patch moves the following functions from main.cpp (the main cpp
file for the standalone executable that is used to create the built-in
functions) to standalone_scaffolding.cpp, so that they can be re-used
in other standalone executables:

- initialize_context()*
- _mesa_new_shader()
- _mesa_reference_shader()

*initialize_context contained some code that was specific to main.cpp,
so it was split into two functions: initialize_context() (which
remains in main.cpp), and initialize_context_from_defaults() (which is
in standalone_scaffolding.cpp).

src/glsl/standalone_scaffolding.h

@@ -0,0 +1,54 @@
+/*
+ * Copyright © 2011 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+/* This file declares stripped-down versions of functions that
+ * normally exist outside of the glsl folder, so that they can be used
+ * when running the GLSL compiler standalone (for unit testing or
+ * compiling builtins).
+ */
+
+#pragma once
+#ifndef STANDALONE_SCAFFOLDING_H
+#define STANDALONE_SCAFFOLDING_H
+
+#include "main/mtypes.h"
+
+extern "C" void
+_mesa_reference_shader(struct gl_context *ctx, struct gl_shader **ptr,
+                       struct gl_shader *sh);
+
+extern "C" struct gl_shader *
+_mesa_new_shader(struct gl_context *ctx, GLuint name, GLenum type);
+
+/**
+ * Initialize the given gl_context structure to a reasonable set of
+ * defaults representing the minimum capabilities required by the
+ * OpenGL spec.
+ *
+ * This is used when compiling builtin functions and in testing, when
+ * we don't have a connection to an actual driver.
+ */
+void initialize_context_to_defaults(struct gl_context *ctx, gl_api api);
+
+
+#endif /* STANDALONE_SCAFFOLDING_H */