Set root path to reflect the current javascript file when using load().

This helps us use consistent relative paths in library code.

utils.cpp

@@ -32,6 +32,20 @@ namespace V8GLUtils {
 	  delete[] tmp_js_path;
 	}
 
+        char *pushRootPath(char *new_path) {
+	    char *old_path = root_path;
+	    char *pch = strrchr(new_path, V8GLUtils::separator);
+	    int last_index = pch ? (pch - new_path + 1) : 2;
+	    root_path = new char[last_index + 1];
+	    strncpy(root_path, pch ? new_path : "./", last_index);
+	    root_path[last_index] = '\0';
+	    return old_path;
+	}
+        void popRootPath(char *old_path) {
+	    delete[] root_path;
+	    root_path = old_path;
+	}
+
 	char* getRootPath(void) {
 		return V8GLUtils::root_path;
 	}

utils.h

@@ -6,6 +6,9 @@ namespace V8GLUtils {
 
 		char* getRootPath(void);
 		char* getRealPath(char* file_path);
+
+		char *pushRootPath(char *new_path);
+		void popRootPath(char *old_path);
 };
 
 #endif

v8-gl.cpp

@@ -146,10 +146,15 @@ Handle<Value> load(const Arguments& args) {
 	  //get argument
 	  String::Utf8Value value0(args[i]);
 	  char* arg0 = *value0;
-	  string str(V8GLUtils::getRealPath(arg0));
-	  if(!exec(str)) {
+	  char* filepath = V8GLUtils::getRealPath(arg0);
+
+	  char *old_path = V8GLUtils::pushRootPath(filepath);
+	  bool success = exec(string(filepath));
+	  V8GLUtils::popRootPath(old_path);
+
+	  if(!success) {
 		  fprintf(stderr, "Error reading '%s'.\n", arg0);
-		  return v8::Undefined();
+		  return ThrowException(String::New("Failed to load script"));
 	  }
   }