mesa: added _mesa_compute_version() in new version.c file

2 files changed, 137 insertions, 0 deletions

diff --git a/src/mesa/main/version.c b/src/mesa/main/version.c
new file mode 100644
index 0000000000..9d23c577bd
--- /dev/null
+++ b/src/mesa/main/version.c
@@ -0,0 +1,130 @@
+/*
+ * Mesa 3-D graphics library
+ *
+ * Copyright (C) 2010  VMware, Inc.  All Rights Reserved.
+ *
+ * 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 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 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.
+ */
+
+
+#include "context.h"
+#include "version.h"
+
+
+
+/**
+ * Examine enabled GL extensions to determine GL version.
+ * Return major and minor version numbers.
+ */
+static void
+compute_version(const GLcontext *ctx, GLuint *major, GLuint *minor)
+{
+   const GLboolean ver_1_3 = (ctx->Extensions.ARB_multisample &&
+                              ctx->Extensions.ARB_multitexture &&
+                              ctx->Extensions.ARB_texture_border_clamp &&
+                              ctx->Extensions.ARB_texture_compression &&
+                              ctx->Extensions.ARB_texture_cube_map &&
+                              ctx->Extensions.EXT_texture_env_add &&
+                              ctx->Extensions.ARB_texture_env_combine &&
+                              ctx->Extensions.ARB_texture_env_dot3);
+   const GLboolean ver_1_4 = (ver_1_3 &&
+                              ctx->Extensions.ARB_depth_texture &&
+                              ctx->Extensions.ARB_shadow &&
+                              ctx->Extensions.ARB_texture_env_crossbar &&
+                              ctx->Extensions.ARB_texture_mirrored_repeat &&
+                              ctx->Extensions.ARB_window_pos &&
+                              ctx->Extensions.EXT_blend_color &&
+                              ctx->Extensions.EXT_blend_func_separate &&
+                              ctx->Extensions.EXT_blend_minmax &&
+                              ctx->Extensions.EXT_blend_subtract &&
+                              ctx->Extensions.EXT_fog_coord &&
+                              ctx->Extensions.EXT_multi_draw_arrays &&
+                              ctx->Extensions.EXT_point_parameters &&
+                              ctx->Extensions.EXT_secondary_color &&
+                              ctx->Extensions.EXT_stencil_wrap &&
+                              ctx->Extensions.EXT_texture_lod_bias &&
+                              ctx->Extensions.SGIS_generate_mipmap);
+   const GLboolean ver_1_5 = (ver_1_4 &&
+                              ctx->Extensions.ARB_occlusion_query &&
+                              ctx->Extensions.ARB_vertex_buffer_object &&
+                              ctx->Extensions.EXT_shadow_funcs);
+   const GLboolean ver_2_0 = (ver_1_5 &&
+                              ctx->Extensions.ARB_draw_buffers &&
+                              ctx->Extensions.ARB_point_sprite &&
+                              ctx->Extensions.ARB_shader_objects &&
+                              ctx->Extensions.ARB_vertex_shader &&
+                              ctx->Extensions.ARB_fragment_shader &&
+                              ctx->Extensions.ARB_texture_non_power_of_two &&
+                              ctx->Extensions.EXT_blend_equation_separate &&
+
+			      /* Technically, 2.0 requires the functionality
+			       * of the EXT version.  Enable 2.0 if either
+			       * extension is available, and assume that a
+			       * driver that only exposes the ATI extension
+			       * will fallback to software when necessary.
+			       */
+			      (ctx->Extensions.EXT_stencil_two_side
+			       || ctx->Extensions.ATI_separate_stencil));
+   const GLboolean ver_2_1 = (ver_2_0 &&
+                              ctx->Extensions.ARB_shading_language_120 &&
+                              ctx->Extensions.EXT_pixel_buffer_object &&
+                              ctx->Extensions.EXT_texture_sRGB);
+   if (ver_2_1) {
+      *major = 2;
+      *minor = 1;
+   }
+   else if (ver_2_0) {
+      *major = 2;
+      *minor = 0;
+   }
+   else if (ver_1_5) {
+      *major = 1;
+      *minor = 5;
+   }
+   else if (ver_1_4) {
+      *major = 1;
+      *minor = 4;
+   }
+   else if (ver_1_3) {
+      *major = 1;
+      *minor = 3;
+   }
+   else {
+      *major = 1;
+      *minor = 2;
+   }
+}
+
+
+/**
+ * Set the context's VersionMajor, VersionMinor, VersionString fields.
+ * This should only be called once as part of context initialization.
+ */
+void
+_mesa_compute_version(GLcontext *ctx)
+{
+   static const int max = 100;
+
+   compute_version(ctx, &ctx->VersionMajor, &ctx->VersionMinor);
+   
+   ctx->VersionString = (char *) _mesa_malloc(max);
+   if (ctx->VersionString) {
+      _mesa_snprintf(ctx->VersionString, max, "%u.%u Mesa " MESA_VERSION_STRING,
+                     ctx->VersionMajor, ctx->VersionMinor);
+   }
+}
diff --git a/src/mesa/main/version.h b/src/mesa/main/version.h
index dc55cb7ccc..d521569f8d 100644
--- a/src/mesa/main/version.h
+++ b/src/mesa/main/version.h
@@ -28,6 +28,9 @@
 #define VERSION_H
 
 
+#include "mtypes.h"
+
+
 /* Mesa version */
 #define MESA_MAJOR 7
 #define MESA_MINOR 8
@@ -50,4 +53,8 @@
 #define OPENGL_VERSION_CODE OPENGL_VERSION(OPENGL_MAJOR, OPENGL_MINOR, OPENGL_PATCH)
 
 
+extern void
+_mesa_compute_version(GLcontext *ctx);
+
+
 #endif /* VERSION_H */