Implementing RPN expression re-initialization

rpn_jit.c

@@ -58,6 +58,28 @@ int rpn_expr_init(rpn_expr_t* expr, const unsigned char stack_sz,
 	return 0;
 }
 
+int rpn_expr_reinit(rpn_expr_t* expr)
+{
+#ifdef DEBUG
+	if(!expr)
+	{
+		dprintf(2, "Error, NULL ptr given as expression to rpn_expr_compile");
+		errno = EINVAL;
+		return -1;
+	}
+#endif
+	bzero(expr->code_map, expr->code_map_sz);
+	bzero(expr->stack, sizeof(unsigned long) * stack_sz);
+	if(_rpn_expr_init_map(expr) < 0)
+	{
+		snprintf(expr->err_reason, 128, 
+			"Unable to re-init code map : %s", strerror(errno));
+		free(expr->expr);
+		expr->state = RPN_ERROR;
+		return -1;
+	}
+}
+
 int rpn_expr_compile(rpn_expr_t *expr, const char *code)
 {
 #ifdef DEBUG
@@ -445,12 +467,15 @@ int _rpn_code_part_cpy(rpn_expr_t *expr, const void *code_part,
 
 int _rpn_expr_init_map(rpn_expr_t* expr)
 {
-	expr->code_map_sz = RPN_MAP_CHUNK;
-	expr->code_map = mmap(NULL, expr->code_map_sz, PROT_READ | PROT_WRITE,
-		MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
-	if(!expr->code_map)
+	if(!expr->code_map_sz)
 	{
-		return -1;
+		expr->code_map_sz = RPN_MAP_CHUNK;
+		expr->code_map = mmap(NULL, expr->code_map_sz, PROT_READ | PROT_WRITE,
+			MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+		if(!expr->code_map)
+		{
+			return -1;
+		}
 	}
 	expr->code_map_ptr = expr->code_map;
 	if(CODE_PART_CPY(expr, rpn_exec))

rpn_jit.h

@@ -146,6 +146,11 @@ struct rpn_expr_s
 int rpn_expr_init(rpn_expr_t* expr, const unsigned char stack_sz,
 	  const size_t args_count);
 
+/**@brief Reinit an existing @ref rpn_expr_s
+ * @param expr
+ */
+int rpn_expr_reinit(rpn_expr_t* expr);
+
 /**@brief Starts a new initialized expression from an expression string
  * @param expr Pointer on an intialized expression ( see @ref rpn_expr_init )
  * @param code '\0' terminated string representing the RPN expr