Truncate delay when peer closes connection. Bug 348

[exim.git] / src / src / acl.c

diff --git a/src/src/acl.c b/src/src/acl.c
index e79c87f83daa5e8ff6ae0588b0527961f36cab63..dae31011784ce69379907b0b5356e6962f1f7826 100644 (file)
--- a/src/src/acl.c
+++ b/src/src/acl.c
@@ -3480,6 +3480,34 @@ for (; cb != NULL; cb = cb->next)
             debug_printf("delay skipped in -bh checking mode\n");
           }
 
+       /* NOTE 1: Remember that we may be
+        dealing with stdin/stdout here, in addition to TCP/IP connections.
+        Also, delays may be specified for non-SMTP input, where smtp_out and
+        smtp_in will be NULL. Whatever is done must work in all cases.
+
+        NOTE 2: The added feature of flushing the output before a delay must
+        apply only to SMTP input. Hence the test for smtp_out being non-NULL.
+        */
+
+        else
+          {
+          if (smtp_out != NULL && !disable_delay_flush)
+           mac_smtp_fflush();
+
+#if !defined(NO_POLL_H) && defined (_GNU_SOURCE)
+           {
+           struct pollfd p;
+           nfds_t n = 0;
+           if (smtp_out)
+             {
+             p.fd = fileno(smtp_out);
+             p.events = POLLRDHUP;
+             n = 1;
+             }
+           if (poll(&p, n, delay*1000) > 0)
+             HDEBUG(D_acl) debug_printf("delay cancelled by peer close\n");
+           }
+#else
         /* It appears to be impossible to detect that a TCP/IP connection has
         gone away without reading from it. This means that we cannot shorten
         the delay below if the client goes away, because we cannot discover
@@ -3489,20 +3517,10 @@ for (; cb != NULL; cb = cb->next)
         Exim process is not held up unnecessarily. However, it seems that we
         can't. The poll() function does not do the right thing, and in any case
         it is not always available.
-
-        NOTE 1: If ever this state of affairs changes, remember that we may be
-        dealing with stdin/stdout here, in addition to TCP/IP connections.
-        Also, delays may be specified for non-SMTP input, where smtp_out and
-        smtp_in will be NULL. Whatever is done must work in all cases.
-
-        NOTE 2: The added feature of flushing the output before a delay must
-        apply only to SMTP input. Hence the test for smtp_out being non-NULL.
         */
 
-        else
-          {
-          if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
           while (delay > 0) delay = sleep(delay);
+#endif
           }
         }
       }