Handling of initial protocol error changed

The client accepts a long(er) response time when waiting for server to
enable RFC2217 (telnet option).

Bug in hangling of rx timeout fixed

src/telnet_basic.c

@@ -7,6 +7,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
+#include <errno.h>
 
 #include "telnet.h"
 #include "telnet_param.h"
@@ -284,12 +285,12 @@ int telnet_open(tn_ctx_t *tcc, int mode)
     while (1)
     {
         res = tcc->srv_rx(tcc->cctx, 1000);
-        if (res <= 0)
+        if (res < 0)
-            return -1;
+            return errno;
         else if (tcc->mode_rfc2217)
             return 0;
-        else if (t - time(NULL) > 2)
+        else if (time(NULL) - t > 10)
-            return -1;
+            return EPROTO;
     }
 }
 

src/ttynvt.c

@@ -470,9 +470,9 @@ static void ttynvt_open(fuse_req_t req, struct fuse_file_info *info)
 
     res =
         telnet_open(tty->tn, ttynvt_param.raw ? TN_MODE_RAW : TN_MODE_TELNET);
-    if (res < 0)
+    if (res != 0)
     {
-        errno = EPROTO;
+        errno = res;
         goto open_err;
     }