Add a vsl_catchup varnishtest function

This enables waiting for the logging thread to idle to make sure all
generated log is caught.

Conflicts:
	bin/varnishtest/vtc_varnish.c

bin/varnishtest/vtc_varnish.c

@@ -79,6 +79,7 @@ struct varnish {
 
 	unsigned		vsl_tag_count[256];
 
+	volatile int		vsl_rec;
 	volatile int		vsl_idle;
 };
 
@@ -186,6 +187,16 @@ wait_running(const struct varnish *v)
  * Varnishlog gatherer thread
  */
 
+static void
+vsl_catchup(const struct varnish *v)
+{
+	int vsl_idle;
+
+	vsl_idle = v->vsl_idle;
+	while (vsl_idle == v->vsl_idle)
+		VTIM_sleep(0.1);
+}
+
 static void *
 varnishlog_thread(void *priv)
 {
@@ -231,6 +242,7 @@ varnishlog_thread(void *priv)
 		if (i == 0) {
 			v->vsl_idle++;
 			/* Nothing to do but wait */
+			v->vsl_idle++;
 			VTIM_sleep(0.1);
 			continue;
 		} else if (i == -2) {
@@ -994,6 +1006,10 @@ varnish_expect(const struct varnish *v, char * const *av)
  *         a correct value. OP can be ==, >, >=, <, <=. For example::
  *
  *                 varnish v1 -expect SMA.s1.g_space > 1000000
+ *
+ * \-vsl_catchup
+ *         Wait until the logging thread has idled to make sure that all
+ *         the generated log is flushed
  */
 
 void
@@ -1130,6 +1146,10 @@ cmd_varnish(CMD_ARGS)
 			varnish_wait(v);
 			continue;
 		}
+		if (!strcmp(*av, "-vsl_catchup")) {
+			vsl_catchup(v);
+			continue;
+		}
 		vtc_log(v->vl, 0, "Unknown varnish argument: %s", *av);
 	}
 }