Prefer exact matches in varnishadm backend.set_health.

Fixes: #1349

bin/varnishd/cache/cache_backend_cfg.c

@@ -288,7 +288,7 @@ backend_find(struct cli *cli, const char *matcher, bf_func *func, void *priv)
 	const char *port_b = NULL;
 	ssize_t port_l = 0;
 	int found = 0;
-	int i;
+	int i, j;
 
 	name_b = matcher;
 	if (matcher != NULL) {
@@ -342,22 +342,33 @@ backend_find(struct cli *cli, const char *matcher, bf_func *func, void *priv)
 			}
 		}
 	}
-	VTAILQ_FOREACH(b, &backends, list) {
-		CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
-		if (port_b != NULL && strncmp(b->port, port_b, port_l) != 0)
-			continue;
-		if (name_b != NULL && strncmp(b->vcl_name, name_b, name_l) != 0)
-			continue;
-		if (ip_b != NULL &&
-		    (b->ipv4_addr == NULL ||
-		      strncmp(b->ipv4_addr, ip_b, ip_l)) &&
-		    (b->ipv6_addr == NULL ||
-		      strncmp(b->ipv6_addr, ip_b, ip_l)))
+
+	for (j = 0; j < 2; ++j) {
+		if (j == 0 && name_b == NULL)
 			continue;
-		found++;
-		i = func(cli, b, priv);
-		if (i)
-			return(i);
+		VTAILQ_FOREACH(b, &backends, list) {
+			CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
+			if (port_b != NULL &&
+			    strncmp(b->port, port_b, port_l) != 0)
+				continue;
+			if (name_b != NULL &&
+			    strncmp(b->vcl_name, name_b, name_l) != 0)
+				continue;
+			if (j == 0 && b->vcl_name[name_l] != '\0')
+				continue;
+			if (ip_b != NULL &&
+			    (b->ipv4_addr == NULL ||
+				strncmp(b->ipv4_addr, ip_b, ip_l)) &&
+			    (b->ipv6_addr == NULL ||
+				strncmp(b->ipv6_addr, ip_b, ip_l)))
+				continue;
+			found++;
+			i = func(cli, b, priv);
+			if (i)
+				return(i);
+			if (j == 0)
+				return (1);
+		}
 	}
 	return (found);
 }

bin/varnishtest/tests/r01349.vtc

+varnishtest "Exact matching for varnishadm backend.set_health"
+
+server s1 -repeat 2 {
+	rxreq
+	txresp -hdr "Backend: b1"
+} -start
+
+server s2 -repeat 2 {
+       rxreq
+       txresp -hdr "Backend: b"
+} -start
+
+varnish v1 -vcl {
+	backend b1 {
+		.host = "${s1_addr}";
+		.port = "${s1_port}";
+	}
+
+	backend b {
+		.host = "${s2_addr}";
+		.port = "${s2_port}";
+	}
+
+	sub vcl_recv {
+		return(pass);
+	}
+
+	sub vcl_backend_fetch {
+		if (bereq.http.backend == "b1") {
+			set bereq.backend = b1;
+		}
+		else {
+			set bereq.backend = b;
+		}
+	}
+
+} -start
+
+varnish v1 -cliok "backend.list b"
+
+client c1 {
+	txreq -hdr "Backend: b1"
+	rxresp
+	expect resp.status == 200
+	expect resp.http.backend == "b1"
+
+	txreq -hdr "Backend: b"
+	rxresp
+	expect resp.status == 200
+	expect resp.http.backend == "b"
+} -run
+
+varnish v1 -cliok "backend.set_health b sick"
+
+client c1 {
+	txreq -hdr "Backend: b1"
+	rxresp
+	expect resp.status == 200
+	expect resp.http.backend == "b1"
+
+	txreq -hdr "Backend: b"
+	rxresp
+	expect resp.status == 503
+} -run
+
+varnish v1 -clierr 106 "backend.set_health b(1.2.3.4:) healthy"