keep previous test to avoid any behavior change

diff --git a/main/streams/streams.c b/main/streams/streams.c
index 7bc4c9ddb56df7f2ccfd4e6530e9dbb80fdd44bf..cb80e9a16b5fe96b6f7bd5dc14cc90ce9f00c048 100644 (file)
--- a/main/streams/streams.c
+++ b/main/streams/streams.c
@@ -1535,8 +1535,10 @@ PHPAPI int _php_stream_copy_to_stream_ex(php_stream *src, php_stream *dest, size
 
                        *len = didwrite;
 
-                       /* read bytes match written */
-                       if (mapped == didwrite) {
+                       /* we've got at least 1 byte to read
+                        * less than 1 is an error
+                        * AND read bytes match written */
+                       if (mapped > 0 && mapped == didwrite) {
                                return SUCCESS;
                        }
                        return FAILURE;