If we are going to start the client automatically, test that the

accept-sockets can actually be bound before we muck about with
daemon() or SHM files.

Belived to be implicated in #1262

bin/varnishd/mgt/mgt.h

@@ -44,6 +44,8 @@ void MGT_Run(void);
 void mgt_stop_child(void);
 void mgt_got_fd(int fd);
 void MGT_Child_Cli_Fail(void);
+int MGT_open_sockets(void);
+void MGT_close_sockets(void);
 
 /* mgt_cli.c */
 

bin/varnishd/mgt/mgt_child.c

@@ -222,13 +222,13 @@ mgt_child_inherit(int fd, const char *what)
  * (The child is priv-sep'ed, so it can't do it.)
  */
 
-static int
-open_sockets(void)
+int
+MGT_open_sockets(void)
 {
-	struct listen_sock *ls, *ls2;
+	struct listen_sock *ls;
 	int good = 0;
 
-	VTAILQ_FOREACH_SAFE(ls, &heritage.socks, list, ls2) {
+	VTAILQ_FOREACH(ls, &heritage.socks, list) {
 		if (ls->sock >= 0) {
 			good++;
 			continue;
@@ -248,8 +248,8 @@ open_sockets(void)
 
 /*--------------------------------------------------------------------*/
 
-static void
-close_sockets(void)
+void
+MGT_close_sockets(void)
 {
 	struct listen_sock *ls;
 
@@ -326,7 +326,7 @@ mgt_launch_child(struct cli *cli)
 	if (child_state != CH_STOPPED && child_state != CH_DIED)
 		return;
 
-	if (open_sockets() != 0) {
+	if (MGT_open_sockets() != 0) {
 		child_state = CH_STOPPED;
 		if (cli != NULL) {
 			VCLI_SetResult(cli, CLIS_CANT);
@@ -410,7 +410,7 @@ mgt_launch_child(struct cli *cli)
 	mgt_child_inherit(heritage.cli_out, NULL);
 	closex(&heritage.cli_out);
 
-	close_sockets();
+	MGT_close_sockets();
 
 	child_std_vlu = VLU_New(NULL, child_line, 0);
 	AN(child_std_vlu);

bin/varnishd/mgt/mgt_main.c

@@ -602,6 +602,15 @@ main(int argc, char * const *argv)
 	if (C_flag)
 		exit (0);
 
+	if (!d_flag) {
+		if (MGT_open_sockets()) {
+			fprintf(stderr,
+			    "Failed to open (any) accept sockets.\n");
+			exit(1);
+		}
+		MGT_close_sockets();
+	}
+
 	/* If no -s argument specified, process default -s argument */
 	if (!s_arg_given)
 		STV_Config(s_arg);