X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/1d717e1c110562fd6bf28478c79f180cafeba776..5c161fa615ab4a2d40170fedd71d1b9a7f079ff6:/src/src/smtp_out.c

diff --git a/src/src/smtp_out.c b/src/src/smtp_out.c
index 96ee15282..911dd537e 100644
--- a/src/src/smtp_out.c
+++ b/src/src/smtp_out.c
@@ -3,6 +3,7 @@
 *************************************************/
 
 /* Copyright (c) University of Cambridge 1995 - 2018 */
+/* Copyright (c) The Exim Maintainers 2020 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* A number of functions for driving outgoing SMTP calls. */
@@ -63,8 +64,8 @@ if (is_tainted(expint))
   return FALSE;
   }
 
-while (isspace(*expint)) expint++;
-if (*expint == 0) return TRUE;
+Uskip_whitespace(&expint);
+if (!*expint) return TRUE;
 
 while ((iface = string_nextinlist(&expint, &sep, big_buffer,
           big_buffer_size)))
@@ -374,7 +375,7 @@ smtp_port_for_connect(host_item * host, int port)
 {
 if (host->port != PORT_NONE)
   {
-  HDEBUG(D_transport|D_acl|D_v)
+  HDEBUG(D_transport|D_acl|D_v) if (port != host->port)
     debug_printf_indent("Transport port=%d replaced by host-specific port=%d\n", port,
       host->port);
   port = host->port;
@@ -500,7 +501,7 @@ else
     rc = n;
     }
   else
-
+    {
     rc = send(outblock->cctx->sock, outblock->buffer, n,
 #ifdef MSG_MORE
 	      more ? MSG_MORE : 0
@@ -508,6 +509,17 @@ else
 	      0
 #endif
 	     );
+
+#if defined(__linux__)
+    /* This is a workaround for a current linux kernel bug: as of
+    5.6.8-200.fc31.x86_64  small (<MSS) writes get delayed by about 200ms,
+    This is despite NODELAY being active.
+    https://bugzilla.redhat.com/show_bug.cgi?id=1803806 */
+
+    if (!more)
+      setsockopt(outblock->cctx->sock, IPPROTO_TCP, TCP_CORK, &off, sizeof(off));
+#endif
+    }
   }
 
 if (rc <= 0)
@@ -597,7 +609,7 @@ if (format)
       while (!isspace(*p)) p++;
       while (isspace(*p)) p++;
       }
-    while (*p != 0) *p++ = '*';
+    while (*p) *p++ = '*';
     }
 
   HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP>> %s\n", big_buffer);