Allow empty needle in mb_str(i)pos

Author: Girgias

ext/mbstring/mbstring.c

@@ -2110,11 +2110,6 @@ PHP_FUNCTION(mb_strpos)
 		}
 	}
 
-	if (needle.len == 0) {
-		php_error_docref(NULL, E_WARNING, "Empty delimiter");
-		RETURN_FALSE;
-	}
-
 	n = mbfl_strpos(&haystack, &needle, offset, reverse);
 	if (!mbfl_is_error(n)) {
 		RETVAL_LONG(n);
@@ -2222,11 +2217,6 @@ PHP_FUNCTION(mb_stripos)
 		return;
 	}
 
-	if (needle.len == 0) {
-		php_error_docref(NULL, E_WARNING, "Empty delimiter");
-		RETURN_FALSE;
-	}
-
 	n = php_mb_stripos(0, (char *)haystack.val, haystack.len, (char *)needle.val, needle.len, offset, from_encoding);
 
 	if (!mbfl_is_error(n)) {
@@ -2279,11 +2269,6 @@ PHP_FUNCTION(mb_strstr)
 		RETURN_FALSE;
 	}
 
-	if (needle.len == 0) {
-		php_error_docref(NULL, E_WARNING, "Empty delimiter");
-		RETURN_FALSE;
-	}
-
 	n = mbfl_strpos(&haystack, &needle, 0, 0);
 	if (!mbfl_is_error(n)) {
 		if (part) {
@@ -2383,11 +2368,6 @@ PHP_FUNCTION(mb_stristr)
 		RETURN_FALSE;
 	}
 
-	if (!needle.len) {
-		php_error_docref(NULL, E_WARNING, "Empty delimiter");
-		RETURN_FALSE;
-	}
-
 	n = php_mb_stripos(0, (char *)haystack.val, haystack.len, (char *)needle.val, needle.len, 0, from_encoding);
 	if (mbfl_is_error(n)) {
 		RETURN_FALSE;