Exercise the VSC's created from VMODs

bin/varnishtest/tests/m00000.vtc

@@ -13,10 +13,12 @@ varnish v1 -vcl+backend {
 
 	sub vcl_init {
 		new objx = debug.obj();
+		debug.vsc_new();
 	}
 
 	sub vcl_recv {
 		debug.rot52(req);
+		debug.vsc_count();
 	}
 
 	sub vcl_deliver {
@@ -36,6 +38,8 @@ varnish v1 -vcl+backend {
 	}
 } -start
 
+varnish v1 -expect DEBUG.count == 0
+
 client c1 {
 	txreq -url "/bar"
 	rxresp
@@ -50,6 +54,8 @@ client c1 {
 	expect resp.http.not == -1
 } -run
 
+varnish v1 -expect DEBUG.count == 1
+
 logexpect l1 -v v1 -g raw -d 1 {
 	expect * 1001 VCL_call		{^DELIVER}
 	expect 0 =    RespUnset	{^foo: bAr}

lib/libvmod_debug/VSC_debug.vsc

@@ -5,7 +5,7 @@
 
 	Test counters from vmod_debug
 
-.. varnish_vsc:: foo
+.. varnish_vsc:: count
 	:type:		counter
 	:level:		debug
 	:oneliner:	arbitrary counter

lib/libvmod_debug/vmod.vcc

@@ -170,6 +170,10 @@ $Function VOID vsc_new()
 
 Add a vsc
 
+$Function VOID vsc_count(INT val = 1)
+
+Update counter
+
 $Function VOID vsc_destroy()
 
 Remove a vsc

lib/libvmod_debug/vmod_debug.c

@@ -370,6 +370,14 @@ xyzzy_vsc_new(VRT_CTX)
 	AZ(pthread_mutex_unlock(&vsc_mtx));
 }
 
+VCL_VOID
+xyzzy_vsc_count(VRT_CTX, VCL_INT cnt)
+{
+	(void)ctx;
+	AN(vsc);
+	vsc->count += cnt;
+}
+
 VCL_VOID
 xyzzy_vsc_destroy(VRT_CTX)
 {