Added concept of interned strings. All strings constants known at compile time are allocated in a single copy and never changed.

1 files changed, 8 insertions, 4 deletions

diff --git a/Zend/zend_constants.c b/Zend/zend_constants.c
index 0543903e84..1743ffd2a8 100644
--- a/Zend/zend_constants.c
+++ b/Zend/zend_constants.c
@@ -32,13 +32,15 @@ void free_zend_constant(zend_constant *c)
 	if (!(c->flags & CONST_PERSISTENT)) {
 		zval_dtor(&c->value);
 	}
-	free(c->name);
+	str_free(c->name);
 }
 
 
 void copy_zend_constant(zend_constant *c)
 {
-	c->name = zend_strndup(c->name, c->name_len - 1);
+	if (!IS_INTERNED(c->name)) {
+		c->name = zend_strndup(c->name, c->name_len - 1);
+	}
 	if (!(c->flags & CONST_PERSISTENT)) {
 		zval_copy_ctor(&c->value);
 	}
@@ -422,12 +424,14 @@ ZEND_API int zend_register_constant(zend_constant *c TSRMLS_DC)
 		/* keep in mind that c->name_len already contains the '\0' */
 		lowercase_name = estrndup(c->name, c->name_len-1);
 		zend_str_tolower(lowercase_name, c->name_len-1);
+		lowercase_name = CG(new_interned_string)(lowercase_name, c->name_len, 1 TSRMLS_CC);
 		name = lowercase_name;
 	} else {
 		char *slash = strrchr(c->name, '\\');
 		if(slash) {
 			lowercase_name = estrndup(c->name, c->name_len-1);
 			zend_str_tolower(lowercase_name, slash-c->name);
+			lowercase_name = CG(new_interned_string)(lowercase_name, c->name_len, 1 TSRMLS_CC);
 			name = lowercase_name;
 		} else {
 			name = c->name;
@@ -437,13 +441,13 @@ ZEND_API int zend_register_constant(zend_constant *c TSRMLS_DC)
 	if ((strncmp(name, "__COMPILER_HALT_OFFSET__", sizeof("__COMPILER_HALT_OFFSET__") - 1) == 0) ||
 			zend_hash_add(EG(zend_constants), name, c->name_len, (void *) c, sizeof(zend_constant), NULL)==FAILURE) {
 		zend_error(E_NOTICE,"Constant %s already defined", name);
-		free(c->name);
+		str_free(c->name);
 		if (!(c->flags & CONST_PERSISTENT)) {
 			zval_dtor(&c->value);
 		}
 		ret = FAILURE;
 	}
-	if (lowercase_name) {
+	if (lowercase_name && !IS_INTERNED(lowercase_name)) {
 		efree(lowercase_name);
 	}
 	return ret;