glsl: Parse optional version directive.

1 files changed, 150 insertions, 0 deletions

diff --git a/src/glsl/pp/sl_pp_version.c b/src/glsl/pp/sl_pp_version.c
new file mode 100644
index 00000000000..f4b4b829d1e
--- /dev/null
+++ b/src/glsl/pp/sl_pp_version.c
@@ -0,0 +1,150 @@
+/**************************************************************************
+ * 
+ * Copyright 2009 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, sub license, 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 NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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 "sl_pp_version.h"
+
+
+static int
+_parse_integer(const char *input,
+               unsigned int *number)
+{
+   unsigned int n = 0;
+
+   while (*input >= '0' && *input <= '9') {
+      if (n * 10 < n) {
+         /* Overflow. */
+         return -1;
+      }
+
+      n = n * 10 + (*input++ - '0');
+   }
+
+   if (*input != '\0') {
+      /* Invalid decimal number. */
+      return -1;
+   }
+
+   *number = n;
+   return 0;
+}
+
+
+int
+sl_pp_version(const struct sl_pp_token_info *input,
+              unsigned int *version,
+              unsigned int *tokens_eaten)
+{
+   unsigned int i = 0;
+   int found_hash = 0;
+   int found_version = 0;
+   int found_number = 0;
+
+   /* Default values if `#version' is not present. */
+   *version = 110;
+   *tokens_eaten = 0;
+
+   /* Skip whitespace and newlines and seek for hash. */
+   while (!found_hash) {
+      switch (input[i].token) {
+      case SL_PP_WHITESPACE:
+      case SL_PP_NEWLINE:
+         i++;
+         break;
+
+      case SL_PP_HASH:
+         i++;
+         found_hash = 1;
+         break;
+
+      default:
+         return 0;
+      }
+   }
+
+   /* Skip whitespace and seek for `version'. */
+   while (!found_version) {
+      switch (input[i].token) {
+      case SL_PP_WHITESPACE:
+         i++;
+         break;
+
+      case SL_PP_IDENTIFIER:
+         if (strcmp(input[i].data.identifier, "version")) {
+            return 0;
+         }
+         i++;
+         found_version = 1;
+         break;
+
+      default:
+         return 0;
+      }
+   }
+
+   /* Skip whitespace and seek for version number. */
+   while (!found_number) {
+      switch (input[i].token) {
+      case SL_PP_WHITESPACE:
+         i++;
+         break;
+
+      case SL_PP_NUMBER:
+         if (_parse_integer(input[i].data.number, version)) {
+            /* Expected version number. */
+            return -1;
+         }
+         i++;
+         found_number = 1;
+         break;
+
+      default:
+         /* Expected version number. */
+         return -1;
+      }
+   }
+
+   /* Skip whitespace and seek for either newline or eof. */
+   for (;;) {
+      switch (input[i].token) {
+      case SL_PP_WHITESPACE:
+         i++;
+         break;
+
+      case SL_PP_NEWLINE:
+      case SL_PP_EOF:
+         i++;
+         *tokens_eaten = i;
+         return 0;
+
+      default:
+         /* Expected end of line. */
+         return -1;
+      }
+   }
+
+   /* Should not get here. */
+}