From 000b8544c65e017e4898225f349853394c38f497 Mon Sep 17 00:00:00 2001
From: Jacob Barthelmeh <jacob@wolfssl.com>
Date: Wed, 30 Sep 2020 13:22:07 -0600
Subject: [PATCH] add peek when waiting for data

---
 examples/echoserver/echoserver.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/examples/echoserver/echoserver.c b/examples/echoserver/echoserver.c
index fb4d598..6bb1865 100644
--- a/examples/echoserver/echoserver.c
+++ b/examples/echoserver/echoserver.c
@@ -896,6 +896,7 @@ static int shell_worker(thread_ctx_t* threadCtx)
  * returns 0 on success
  */
 static int sftp_worker(thread_ctx_t* threadCtx) {
+    byte tmp[1];
     int ret   = WS_SUCCESS;
     int error = WS_SUCCESS;
     SOCKET_T sockfd;
@@ -910,7 +911,13 @@ static int sftp_worker(thread_ctx_t* threadCtx) {
                 printf("... sftp server would write block\n");
         }
 
-        select_ret = tcp_select(sockfd, TEST_SFTP_TIMEOUT);
+        if (wolfSSH_stream_peek(threadCtx->ssh, tmp, 1) > 0) {
+            select_ret = WS_SELECT_RECV_READY;
+        }
+        else {
+            select_ret = tcp_select(sockfd, TEST_SFTP_TIMEOUT);
+        }
+
         if (select_ret == WS_SELECT_RECV_READY ||
             select_ret == WS_SELECT_ERROR_READY ||
             error == WS_WANT_WRITE)