From: Timo Sirainen <timo.sirainen@dovecot.fi>
Date: Sun, 26 Jun 2016 20:04:00 +0000 (+0300)
Subject: master: Allow stopping specific services via master socket.
X-Git-Tag: 2.3.0.rc1~3380
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=164f8e81a078c7b8f679fdd04892ffc9ba14bfa0;p=thirdparty%2Fdovecot%2Fcore.git

master: Allow stopping specific services via master socket.
---

diff --git a/src/master/Makefile.am b/src/master/Makefile.am
index 9d3ad7844f..ef7955ff31 100644
--- a/src/master/Makefile.am
+++ b/src/master/Makefile.am
@@ -25,6 +25,7 @@ dovecot_SOURCES = \
 	capabilities-posix.c \
 	dup2-array.c \
 	main.c \
+	master-client.c \
 	master-settings.c \
 	service-anvil.c \
 	service-listen.c \
@@ -39,6 +40,7 @@ noinst_HEADERS = \
 	capabilities.h \
 	common.h \
 	dup2-array.h \
+	master-client.h \
 	master-settings.h \
 	sd-daemon.h \
 	service-anvil.h \
diff --git a/src/master/main.c b/src/master/main.c
index 533d4d8056..ab67dc4dd3 100644
--- a/src/master/main.c
+++ b/src/master/main.c
@@ -18,6 +18,7 @@
 #include "master-service-settings.h"
 #include "askpass.h"
 #include "capabilities.h"
+#include "master-client.h"
 #include "service.h"
 #include "service-anvil.h"
 #include "service-listen.h"
@@ -526,6 +527,7 @@ static void main_init(const struct master_settings *set)
 	create_pid_file(pidfile_path);
 	create_config_symlink(set);
 	instance_update(set);
+	master_clients_init();
 
 	services_monitor_start(services);
 }
@@ -542,6 +544,7 @@ static void global_dead_pipe_close(void)
 
 static void main_deinit(void)
 {
+	master_clients_deinit();
 	instance_update_now(instances);
 	timeout_remove(&to_instance);
 	master_instance_list_deinit(&instances);
diff --git a/src/master/master-client.c b/src/master/master-client.c
new file mode 100644
index 0000000000..32cfbc3eb4
--- /dev/null
+++ b/src/master/master-client.c
@@ -0,0 +1,100 @@
+/* Copyright (c) 2016 Dovecot authors, see the included COPYING file */
+
+#include "common.h"
+#include "ostream.h"
+#include "connection.h"
+#include "service.h"
+#include "service-monitor.h"
+#include "master-client.h"
+
+struct master_client {
+	struct connection conn;
+};
+
+static int
+master_client_stop(struct master_client *client, const char *const *args)
+{
+	struct service *service;
+	const char *reply = "+\n";
+
+	for (unsigned int i = 0; args[i] != NULL; i++) {
+		service = service_lookup(services, args[i]);
+		if (service == NULL)
+			reply = t_strdup_printf("-Unknown service: %s\n", args[i]);
+		else
+			service_monitor_stop_close(service);
+	}
+	o_stream_send_str(client->conn.output, reply);
+	return 1;
+}
+
+static int
+master_client_input_args(struct connection *conn, const char *const *args)
+{
+	struct master_client *client = (struct master_client *)conn;
+	const char *cmd = args[0];
+
+	if (cmd == NULL) {
+		i_error("%s: Empty command", conn->name);
+		return 0;
+	}
+	args++;
+
+	if (strcmp(cmd, "STOP") == 0)
+		return master_client_stop(client, args);
+	i_error("%s: Unknown command: %s", conn->name, cmd);
+	return -1;
+}
+
+static void master_client_destroy(struct connection *conn)
+{
+	struct master_client *client = (struct master_client *)conn;
+
+	connection_deinit(conn);
+	i_free(client);
+}
+
+static const struct connection_settings master_conn_set = {
+	.service_name_in = "master-client",
+	.service_name_out = "master-server",
+	.major_version = 1,
+	.minor_version = 0,
+
+	.input_max_size = 1024,
+	.output_max_size = 1024,
+	.client = FALSE
+};
+
+static const struct connection_vfuncs master_conn_vfuncs = {
+	.destroy = master_client_destroy,
+	.input_args = master_client_input_args
+};
+
+static struct connection_list *master_connections;
+
+void master_client_connected(struct service_list *service_list)
+{
+	struct master_client *client;
+	int fd;
+
+	fd = net_accept(service_list->master_fd, NULL, NULL);
+	if (fd < 0) {
+		if (fd == -2)
+			i_error("net_accept() failed: %m");
+		return;
+	}
+	client = i_new(struct master_client, 1);
+	connection_init_server(master_connections, &client->conn,
+			       "master-client", fd, fd);
+}
+
+void master_clients_init(void)
+{
+	master_connections = connection_list_init(&master_conn_set,
+						  &master_conn_vfuncs);
+}
+
+void master_clients_deinit(void)
+{
+	connection_list_deinit(&master_connections);
+}
diff --git a/src/master/master-client.h b/src/master/master-client.h
new file mode 100644
index 0000000000..7e62edee8a
--- /dev/null
+++ b/src/master/master-client.h
@@ -0,0 +1,9 @@
+#ifndef MASTER_CLIENT_H
+#define MASTER_CLIENT_H
+
+void master_client_connected(struct service_list *service_list);
+
+void master_clients_init(void);
+void master_clients_deinit(void);
+
+#endif
diff --git a/src/master/service-listen.c b/src/master/service-listen.c
index ca5525312f..1d3e399a7e 100644
--- a/src/master/service-listen.c
+++ b/src/master/service-listen.c
@@ -4,7 +4,9 @@
 #include "array.h"
 #include "fd-set-nonblock.h"
 #include "fd-close-on-exec.h"
+#include "ioloop.h"
 #include "net.h"
+#include "master-client.h"
 #ifdef HAVE_SYSTEMD
 #include "sd-daemon.h"
 #endif
@@ -337,6 +339,31 @@ static int services_verify_systemd(struct service_list *service_list)
 }
 #endif
 
+static int services_listen_master(struct service_list *service_list)
+{
+	const char *path;
+	mode_t old_umask;
+
+	path = t_strdup_printf("%s/master", service_list->set->base_dir);
+	old_umask = umask(0600 ^ 0777);
+	service_list->master_fd = net_listen_unix(path, 16);
+	if (service_list->master_fd == -1 && errno == EADDRINUSE) {
+		/* already in use. all the other sockets were fine, so just
+		   delete this and retry. */
+		i_unlink_if_exists(path);
+		service_list->master_fd = net_listen_unix(path, 16);
+	}
+	umask(old_umask);
+
+	if (service_list->master_fd == -1)
+		return 0;
+
+	service_list->io_master =
+		io_add(service_list->master_fd, IO_READ,
+		       master_client_connected, service_list);
+	return 1;
+}
+
 int services_listen(struct service_list *service_list)
 {
 	struct service *const *services;
@@ -347,6 +374,8 @@ int services_listen(struct service_list *service_list)
 		if (ret2 < ret)
 			ret = ret2;
 	}
+	if (ret > 0)
+		ret = services_listen_master(service_list);
 
 #ifdef HAVE_SYSTEMD
 	if (ret > 0)
diff --git a/src/master/service-monitor.c b/src/master/service-monitor.c
index a90c4ebe8c..19655c2c39 100644
--- a/src/master/service-monitor.c
+++ b/src/master/service-monitor.c
@@ -589,6 +589,11 @@ void services_monitor_stop(struct service_list *service_list, bool wait)
 		services_monitor_wait(service_list);
 	}
 
+	if (service_list->io_master != NULL)
+		io_remove(&service_list->io_master);
+	if (service_list->master_fd != -1)
+		i_close_fd(&service_list->master_fd);
+
 	array_foreach(&service_list->services, services)
 		service_monitor_stop(*services);
 
diff --git a/src/master/service.h b/src/master/service.h
index 004a03f4b9..1df29b002b 100644
--- a/src/master/service.h
+++ b/src/master/service.h
@@ -137,6 +137,10 @@ struct service_list {
 	struct service *log;
 	struct service *anvil;
 
+	struct file_listener_settings master_listener_set;
+	struct io *io_master;
+	int master_fd;
+
 	/* nonblocking log fds usd by master */
 	int master_log_fd[2];
 	struct service_process_notify *log_byes;