Fixed bug #53037 (FILTER_FLAG_EMPTY_STRING_NULL is not implemented).

NEWS

@@ -28,6 +28,9 @@ PHP                                                                        NEWS
 - DBA extension:
   . Fixed bug #54242 (dba_insert returns true if key already exists). (Felipe)
 
+- Filter extension:
+  . Fixed bug #53037 (FILTER_FLAG_EMPTY_STRING_NULL is not implemented). (Ilia)
+  
 - LDAP extension:
   . Fixed bug #53339 (Fails to build when compilng with gcc 4.5 and DSO
     libraries). (Clint Byrum, Raphael)

ext/filter/sanitizing_filters.c

@@ -205,7 +205,11 @@ void php_filter_string(PHP_INPUT_FILTER_PARAM_DECL)
 
 	if (new_len == 0) {
 		zval_dtor(value);
-		ZVAL_EMPTY_STRING(value);
+		if (flags & FILTER_FLAG_EMPTY_STRING_NULL) {
+			ZVAL_NULL(value);
+		} else {
+			ZVAL_EMPTY_STRING(value);			
+		}
 		return;
 	}
 }
@@ -280,6 +284,9 @@ void php_filter_unsafe_raw(PHP_INPUT_FILTER_PARAM_DECL)
 		}
 
 		php_filter_encode_html(value, enc);	
+	} else if (flags & FILTER_FLAG_EMPTY_STRING_NULL && Z_STRLEN_P(value) == 0) {
+		zval_dtor(value);
+		ZVAL_NULL(value);
 	}
 }
 /* }}} */

ext/filter/tests/bug53037.phpt

@@ -0,0 +1,14 @@
+--TEST--
+Bug #53037 (FILTER_FLAG_EMPTY_STRING_NULL is not implemented)
+--SKIPIF--
+<?php if (!extension_loaded("filter")) die("skip"); ?>
+--FILE--
+<?php
+var_dump(
+	filter_var("", FILTER_DEFAULT),
+    filter_var("", FILTER_DEFAULT, array('flags' => FILTER_FLAG_EMPTY_STRING_NULL))
+);
+?>
+--EXPECT--	
+string(0) ""
+NULL