glsl: Add preprocessor skeleton for directive parsing.

1 files changed, 157 insertions, 0 deletions

diff --git a/src/glsl/pp/sl_pp_process.c b/src/glsl/pp/sl_pp_process.c
new file mode 100644
index 00000000000..56b8fab52a0
--- /dev/null
+++ b/src/glsl/pp/sl_pp_process.c
@@ -0,0 +1,157 @@
+/**************************************************************************
+ * 
+ * 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 <stdlib.h>
+#include <string.h>
+#include "sl_pp_process.h"
+
+
+enum process_state {
+   state_seek_hash,
+   state_seek_directive,
+   state_seek_newline,
+   state_expand
+};
+
+int
+sl_pp_process(const struct sl_pp_token_info *input,
+              struct sl_pp_token_info **output)
+{
+   unsigned int i = 0;
+   enum process_state state = state_seek_hash;
+   struct sl_pp_token_info *out = NULL;
+   unsigned int out_len = 0;
+   unsigned int out_max = 0;
+
+   for (;;) {
+      struct sl_pp_token_info info;
+      int info_valid = 0;
+
+      switch (input[i].token) {
+      case SL_PP_WHITESPACE:
+         /* Drop whitespace alltogether at this point. */
+         i++;
+         break;
+
+      case SL_PP_NEWLINE:
+      case SL_PP_EOF:
+         /* Preserve newline just for the sake of line numbering. */
+         info = input[i];
+         info_valid = 1;
+         i++;
+         /* Restart directive parsing. */
+         state = state_seek_hash;
+         break;
+
+      case SL_PP_HASH:
+         if (state == state_seek_hash) {
+            i++;
+            state = state_seek_directive;
+         } else {
+            /* Error: unexpected token. */
+            return -1;
+         }
+         break;
+
+      case SL_PP_IDENTIFIER:
+         if (state == state_seek_hash) {
+            info = input[i];
+            info_valid = 1;
+            i++;
+            state = state_expand;
+         } else if (state == state_seek_directive) {
+            i++;
+            state = state_seek_newline;
+         } else if (state == state_expand) {
+            info = input[i];
+            info_valid = 1;
+            i++;
+         } else {
+            i++;
+         }
+         break;
+
+      default:
+         if (state == state_seek_hash) {
+            info = input[i];
+            info_valid = 1;
+            i++;
+            state = state_expand;
+         } else if (state == state_seek_directive) {
+            /* Error: expected directive name. */
+            return -1;
+         } else if (state == state_expand) {
+            info = input[i];
+            info_valid = 1;
+            i++;
+         } else {
+            i++;
+         }
+      }
+
+      if (info_valid) {
+         if (out_len >= out_max) {
+            unsigned int new_max = out_max;
+
+            if (new_max < 0x100) {
+               new_max = 0x100;
+            } else if (new_max < 0x10000) {
+               new_max *= 2;
+            } else {
+               new_max += 0x10000;
+            }
+
+            out = realloc(out, new_max * sizeof(struct sl_pp_token_info));
+            if (!out) {
+               return -1;
+            }
+            out_max = new_max;
+         }
+
+         if (info.token == SL_PP_IDENTIFIER) {
+            info.data.identifier = strdup(info.data.identifier);
+            if (!info.data.identifier) {
+               return -1;
+            }
+         } else if (info.token == SL_PP_NUMBER) {
+            info.data.number = strdup(info.data.number);
+            if (!info.data.number) {
+               return -1;
+            }
+         }
+
+         out[out_len++] = info;
+
+         if (info.token == SL_PP_EOF) {
+            break;
+         }
+      }
+   }
+
+   *output = out;
+   return 0;
+}