structure blocks are now read correctly

src/parser.y

@@ -81,6 +81,11 @@ metaSection: /* empty */
 		$$ = $4;
 		addStat(&$$.stats, $2);
 	}
+           | STRUCTURE_BEGIN
+   {
+   	yyerror("structure block in meta section not yet supported");
+   	YYERROR;
+   }
 ;
 
 parameters: /* empty */
@@ -135,8 +140,19 @@ mainSection: /* empty */
 		$$ = $1;
 		addNode(&$$, newOutputNode($3));
 	}
+           | mainSection STRUCTURE_BEGIN texts structureType text STRUCTURE_END
+   {
+   	if (!checkCharset($3, " \t\n")) {
+   		yyerror("unknown structure block command");
+   		YYERROR;
+   	}
+   	
+   	$$ = $1;
+   }
 ;
 
+structureType: RENDER
+
 statementHeader: STATEMENT_BEGIN blockStatement STATEMENT_END
 	{
 		$$ = $2;

src/tree.c

@@ -1,5 +1,6 @@
 #include <stdlib.h>
 #include <string.h>
+#include <stdbool.h>
 
 #include "common.h"
 #include "tree.h"
@@ -161,3 +162,25 @@ struct template newTemplate() {
 		.tree = newTree()
 	};
 }
+
+bool checkCharset(const char* string, const char* charset) {
+	size_t charsetLength = strlen(charset);
+
+	while (*string != '\0') {
+		bool ok = false;
+		for (size_t i = 0; i < charsetLength; i++) {
+			if (*string == charset[i]) {
+				ok = true;
+				break;
+			}
+		}
+		
+		if (!ok) {
+			return false;
+		}
+	
+		string++;
+	}
+
+	return true;
+}

src/tree.h

@@ -1,6 +1,8 @@
 #ifndef TREE_H_
 #define TREE_H_
 
+#include <stdbool.h>
+
 char* combineStr(char*, char*);
 
 #define TEXT_NODE      (0)
@@ -56,4 +58,6 @@ struct template {
 
 struct template newTemplate();
 
+bool checkCharset(const char*, const char*);
+
 #endif