Replace strncat in filter implementation

In this case we already know exactly where we need to write, no
need to use strncat at all.

Author: nikic

ext/standard/user_filters.c

@@ -292,8 +292,9 @@ static php_stream_filter *user_filter_factory_create(const char *filtername,
 			memcpy(wildcard, filtername, len + 1); /* copy \0 */
 			period = wildcard + (period - filtername);
 			while (period) {
-				*period = '\0';
-				strncat(wildcard, ".*", 2);
+				ZEND_ASSERT(period[0] == '.');
+				period[1] = '*';
+				period[2] = '\0';
 				if (NULL != (fdat = zend_hash_str_find_ptr(BG(user_filter_map), wildcard, strlen(wildcard)))) {
 					period = NULL;
 				} else {

main/streams/filter.c

@@ -239,8 +239,9 @@ PHPAPI php_stream_filter *php_stream_filter_create(const char *filtername, zval
 		memcpy(wildname, filtername, n+1);
 		period = wildname + (period - filtername);
 		while (period && !filter) {
-			*period = '\0';
-			strncat(wildname, ".*", 2);
+			ZEND_ASSERT(period[0] == '.');
+			period[1] = '*';
+			period[2] = '\0';
 			if (NULL != (factory = zend_hash_str_find_ptr(filter_hash, wildname, strlen(wildname)))) {
 				filter = factory->create_filter(filtername, filterparams, persistent);
 			}