service: add cr_errno to criu_resp and send cr_errno in it, v2

v2, set cr_errno only if we have one that is != 0
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-service.c

@@ -88,7 +88,10 @@ static void send_criu_err(int sk, char *msg)
 
 	resp.type = CRIU_REQ_TYPE__EMPTY;
 	resp.success = false;
-	/* XXX -- add optional error code to CriuResp */
+	if (get_cr_errno()) {
+		resp.has_cr_errno = true;
+		resp.cr_errno = get_cr_errno();
+	}
 
 	send_criu_msg(sk, &resp);
 }
@@ -100,6 +103,10 @@ int send_criu_dump_resp(int socket_fd, bool success, bool restored)
 
 	msg.type = CRIU_REQ_TYPE__DUMP;
 	msg.success = success;
+	if (get_cr_errno()) {
+		msg.has_cr_errno = true;
+		msg.cr_errno = get_cr_errno();
+	}
 	msg.dump = &resp;
 
 	resp.has_restored = true;
@@ -114,6 +121,10 @@ static int send_criu_pre_dump_resp(int socket_fd, bool success)
 
 	msg.type = CRIU_REQ_TYPE__PRE_DUMP;
 	msg.success = success;
+	if (get_cr_errno()) {
+		msg.has_cr_errno = true;
+		msg.cr_errno = get_cr_errno();
+	}
 
 	return send_criu_msg(socket_fd, &msg);
 }
@@ -125,6 +136,10 @@ int send_criu_restore_resp(int socket_fd, bool success, int pid)
 
 	msg.type = CRIU_REQ_TYPE__RESTORE;
 	msg.success = success;
+	if (get_cr_errno()) {
+		msg.has_cr_errno = true;
+		msg.cr_errno = get_cr_errno();
+	}
 	msg.restore = &resp;
 
 	resp.pid = pid;

protobuf/rpc.proto

@@ -116,4 +116,6 @@ message criu_resp {
 	optional criu_restore_resp	restore		= 4;
 	optional criu_notify		notify		= 5;
 	optional criu_page_server_info	ps		= 6;
+
+	optional int32			cr_errno	= 7;
 }