libwebsockets_read: update 'len' after lws_handshake_server invocation

diff --git a/lib/handshake.c b/lib/handshake.c
index 25dd3cc..dffd2d2 100644 (file)
--- a/lib/handshake.c
+++ b/lib/handshake.c
@@ -132,11 +132,18 @@ http_postbody:
                if (lws_handshake_client(wsi, &buf, len))
                        goto bail;
 
-               switch (lws_handshake_server(context, wsi, &buf, len)) {
-               case 1:
-                       goto bail;
-               case 2:
-                       goto http_postbody;
+               /* It's possible that we've exhausted our data already, but
+                * lws_handshake_server doesn't update len for us. Figure out how
+                * much was read, so that we can proceed appropriately: */
+               {
+                       unsigned char *last_char = buf;
+                       switch (lws_handshake_server(context, wsi, &buf, len)) {
+                       case 1:
+                               goto bail;
+                       case 2:
+                               len -= (buf - last_char);
+                               goto http_postbody;
+                       }
                }
                break;