core: convert PID 1 to libsystemd-bus

This patch converts PID 1 to libsystemd-bus and thus drops the
dependency on libdbus. The only remaining code using libdbus is a test
case that validates our bus marshalling against libdbus' marshalling,
and this dependency can be turned off.

This patch also adds a couple of things to libsystem-bus, that are
necessary to make the port work:

- Synthesizing of "Disconnected" messages when bus connections are
  severed.

- Support for attaching multiple vtables for the same interface on the
  same path.

This patch also fixes the SetDefaultTarget() and GetDefaultTarget() bus
calls which used an inappropriate signature.

As a side effect we will now generate PropertiesChanged messages which
carry property contents, rather than just invalidation information.

1 files changed, 90 insertions, 176 deletions

diff --git a/src/core/dbus-service.c b/src/core/dbus-service.c
index c888570c4b..c4bfa2c38f 100644
--- a/src/core/dbus-service.c
+++ b/src/core/dbus-service.c
@@ -19,176 +19,92 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <errno.h>
-
 #include "strv.h"
 #include "path-util.h"
+#include "unit.h"
+#include "service.h"
 #include "dbus-unit.h"
 #include "dbus-execute.h"
 #include "dbus-kill.h"
 #include "dbus-cgroup.h"
-#include "dbus-common.h"
-#include "selinux-access.h"
 #include "dbus-service.h"
-
-#define BUS_SERVICE_INTERFACE                                           \
-        " <interface name=\"org.freedesktop.systemd1.Service\">\n"      \
-        "  <property name=\"Type\" type=\"s\" access=\"read\"/>\n"      \
-        "  <property name=\"Restart\" type=\"s\" access=\"read\"/>\n"   \
-        "  <property name=\"PIDFile\" type=\"s\" access=\"read\"/>\n"   \
-        "  <property name=\"NotifyAccess\" type=\"s\" access=\"read\"/>\n" \
-        "  <property name=\"RestartUSec\" type=\"t\" access=\"read\"/>\n" \
-        "  <property name=\"TimeoutStartUSec\" type=\"t\" access=\"read\"/>\n" \
-        "  <property name=\"TimeoutStopUSec\" type=\"t\" access=\"read\"/>\n" \
-        "  <property name=\"WatchdogUSec\" type=\"t\" access=\"read\"/>\n" \
-        "  <property name=\"WatchdogTimestamp\" type=\"t\" access=\"read\"/>\n" \
-        "  <property name=\"WatchdogTimestampMonotonic\" type=\"t\" access=\"read\"/>\n" \
-        "  <property name=\"StartLimitInterval\" type=\"t\" access=\"read\"/>\n" \
-        "  <property name=\"StartLimitBurst\" type=\"u\" access=\"read\"/>\n" \
-        "  <property name=\"StartLimitAction\" type=\"s\" access=\"readwrite\"/>\n" \
-        BUS_UNIT_CGROUP_INTERFACE                                       \
-        BUS_EXEC_COMMAND_INTERFACE("ExecStartPre")                      \
-        BUS_EXEC_COMMAND_INTERFACE("ExecStart")                         \
-        BUS_EXEC_COMMAND_INTERFACE("ExecStartPost")                     \
-        BUS_EXEC_COMMAND_INTERFACE("ExecReload")                        \
-        BUS_EXEC_COMMAND_INTERFACE("ExecStop")                          \
-        BUS_EXEC_COMMAND_INTERFACE("ExecStopPost")                      \
-        BUS_EXEC_CONTEXT_INTERFACE                                      \
-        BUS_KILL_CONTEXT_INTERFACE                                      \
-        BUS_CGROUP_CONTEXT_INTERFACE                                    \
-        "  <property name=\"PermissionsStartOnly\" type=\"b\" access=\"read\"/>\n" \
-        "  <property name=\"RootDirectoryStartOnly\" type=\"b\" access=\"read\"/>\n" \
-        "  <property name=\"RemainAfterExit\" type=\"b\" access=\"read\"/>\n" \
-        BUS_EXEC_STATUS_INTERFACE("ExecMain")                           \
-        "  <property name=\"MainPID\" type=\"u\" access=\"read\"/>\n"   \
-        "  <property name=\"ControlPID\" type=\"u\" access=\"read\"/>\n" \
-        "  <property name=\"BusName\" type=\"s\" access=\"read\"/>\n"   \
-        "  <property name=\"StatusText\" type=\"s\" access=\"read\"/>\n" \
-        "  <property name=\"Result\" type=\"s\" access=\"read\"/>\n"    \
-       " </interface>\n"
-
-#define INTROSPECTION                                                   \
-        DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE                       \
-        "<node>\n"                                                      \
-        BUS_UNIT_INTERFACE                                              \
-        BUS_SERVICE_INTERFACE                                           \
-        BUS_PROPERTIES_INTERFACE                                        \
-        BUS_PEER_INTERFACE                                              \
-        BUS_INTROSPECTABLE_INTERFACE                                    \
-        "</node>\n"
-
-#define INTERFACES_LIST                              \
-        BUS_UNIT_INTERFACES_LIST                     \
-        "org.freedesktop.systemd1.Service\0"
-
-const char bus_service_interface[] = BUS_SERVICE_INTERFACE;
-
-const char bus_service_invalidating_properties[] =
-        "ExecStartPre\0"
-        "ExecStart\0"
-        "ExecStartPost\0"
-        "ExecReload\0"
-        "ExecStop\0"
-        "ExecStopPost\0"
-        "ExecMain\0"
-        "WatchdogTimestamp\0"
-        "WatchdogTimestampMonotonic\0"
-        "MainPID\0"
-        "ControlPID\0"
-        "StatusText\0"
-        "Result\0";
-
-static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_service_append_type, service_type, ServiceType);
-static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_service_append_restart, service_restart, ServiceRestart);
-static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_service_append_notify_access, notify_access, NotifyAccess);
-static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_service_append_service_result, service_result, ServiceResult);
-static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_service_append_start_limit_action, start_limit_action, StartLimitAction);
-static DEFINE_BUS_PROPERTY_SET_ENUM(bus_service_set_start_limit_action, start_limit_action, StartLimitAction);
-
-static const BusProperty bus_exec_main_status_properties[] = {
-        { "ExecMainStartTimestamp",         bus_property_append_usec, "t", offsetof(ExecStatus, start_timestamp.realtime)  },
-        { "ExecMainStartTimestampMonotonic",bus_property_append_usec, "t", offsetof(ExecStatus, start_timestamp.monotonic) },
-        { "ExecMainExitTimestamp",          bus_property_append_usec, "t", offsetof(ExecStatus, exit_timestamp.realtime)   },
-        { "ExecMainExitTimestampMonotonic", bus_property_append_usec, "t", offsetof(ExecStatus, exit_timestamp.monotonic)  },
-        { "ExecMainPID",                    bus_property_append_pid,  "u", offsetof(ExecStatus, pid)                       },
-        { "ExecMainCode",                   bus_property_append_int,  "i", offsetof(ExecStatus, code)                      },
-        { "ExecMainStatus",                 bus_property_append_int,  "i", offsetof(ExecStatus, status)                    },
-        {}
+#include "bus-util.h"
+
+static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_type, service_type, ServiceType);
+static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_result, service_result, ServiceResult);
+static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_restart, service_restart, ServiceRestart);
+static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_notify_access, notify_access, NotifyAccess);
+static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_start_limit_action, start_limit_action, StartLimitAction);
+
+const sd_bus_vtable bus_service_vtable[] = {
+        SD_BUS_VTABLE_START(0),
+        SD_BUS_PROPERTY("Type", "s", property_get_type, offsetof(Service, type), 0),
+        SD_BUS_PROPERTY("Restart", "s", property_get_restart, offsetof(Service, restart), 0),
+        SD_BUS_PROPERTY("PIDFile", "s", NULL, offsetof(Service, pid_file), 0),
+        SD_BUS_PROPERTY("NotifyAccess", "s", property_get_notify_access, offsetof(Service, notify_access), 0),
+        SD_BUS_PROPERTY("RestartUSec", "t", bus_property_get_usec, offsetof(Service, restart_usec), 0),
+        SD_BUS_PROPERTY("TimeoutStartUSec", "t", bus_property_get_usec, offsetof(Service, timeout_start_usec), 0),
+        SD_BUS_PROPERTY("TimeoutStopUSec", "t", bus_property_get_usec, offsetof(Service, timeout_stop_usec), 0),
+        SD_BUS_PROPERTY("WatchdogUSec", "t", bus_property_get_usec, offsetof(Service, watchdog_usec), 0),
+        BUS_PROPERTY_DUAL_TIMESTAMP("WatchdogTimestamp", offsetof(Service, watchdog_timestamp), 0),
+        SD_BUS_PROPERTY("StartLimitInterval", "t", bus_property_get_usec, offsetof(Service, start_limit.interval), 0),
+        SD_BUS_PROPERTY("StartLimitBurst", "u", bus_property_get_unsigned, offsetof(Service, start_limit.burst), 0),
+        SD_BUS_PROPERTY("StartLimitAction", "s", property_get_start_limit_action, offsetof(Service, start_limit_action), 0),
+        SD_BUS_PROPERTY("PermissionsStartOnly", "b", bus_property_get_bool, offsetof(Service, permissions_start_only), 0),
+        SD_BUS_PROPERTY("RootDirectoryStartOnly", "b", bus_property_get_bool, offsetof(Service, root_directory_start_only), 0),
+        SD_BUS_PROPERTY("RemainAfterExit", "b", bus_property_get_bool, offsetof(Service, remain_after_exit), 0),
+        SD_BUS_PROPERTY("GuessMainPID", "b", bus_property_get_bool, offsetof(Service, guess_main_pid), 0),
+        SD_BUS_PROPERTY("MainPID", "u", bus_property_get_pid, offsetof(Service, main_pid), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
+        SD_BUS_PROPERTY("ControlPID", "u", bus_property_get_pid, offsetof(Service, control_pid), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
+        SD_BUS_PROPERTY("BusName", "s", NULL, offsetof(Service, bus_name), 0),
+        SD_BUS_PROPERTY("StatusText", "s", NULL, offsetof(Service, status_text), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
+        SD_BUS_PROPERTY("Result", "s", property_get_result, offsetof(Service, result), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
+        BUS_EXEC_STATUS_VTABLE("ExecMain", offsetof(Service, main_exec_status), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
+        BUS_EXEC_COMMAND_VTABLE("ExecStartPre", offsetof(Service, exec_command[SERVICE_EXEC_START_PRE]), 0),
+        BUS_EXEC_COMMAND_VTABLE("ExecStart", offsetof(Service, exec_command[SERVICE_EXEC_START]), 0),
+        BUS_EXEC_COMMAND_VTABLE("ExecStartPost", offsetof(Service, exec_command[SERVICE_EXEC_START_POST]), 0),
+        BUS_EXEC_COMMAND_VTABLE("ExecReload", offsetof(Service, exec_command[SERVICE_EXEC_RELOAD]), 0),
+        BUS_EXEC_COMMAND_VTABLE("ExecStop", offsetof(Service, exec_command[SERVICE_EXEC_STOP]), 0),
+        BUS_EXEC_COMMAND_VTABLE("ExecStopPost", offsetof(Service, exec_command[SERVICE_EXEC_STOP_POST]), 0),
+        SD_BUS_VTABLE_END
 };
 
-static const BusProperty bus_service_properties[] = {
-        { "Type",                   bus_service_append_type,          "s", offsetof(Service, type)                         },
-        { "Restart",                bus_service_append_restart,       "s", offsetof(Service, restart)                      },
-        { "PIDFile",                bus_property_append_string,       "s", offsetof(Service, pid_file),               true },
-        { "NotifyAccess",           bus_service_append_notify_access, "s", offsetof(Service, notify_access)                },
-        { "RestartUSec",            bus_property_append_usec,         "t", offsetof(Service, restart_usec)                 },
-        { "TimeoutStartUSec",       bus_property_append_usec,         "t", offsetof(Service, timeout_start_usec)           },
-        { "TimeoutStopUSec",        bus_property_append_usec,         "t", offsetof(Service, timeout_stop_usec)            },
-        { "WatchdogUSec",           bus_property_append_usec,         "t", offsetof(Service, watchdog_usec)                },
-        { "WatchdogTimestamp",      bus_property_append_usec,         "t", offsetof(Service, watchdog_timestamp.realtime)  },
-        { "WatchdogTimestampMonotonic",bus_property_append_usec,      "t", offsetof(Service, watchdog_timestamp.monotonic) },
-        { "StartLimitInterval",     bus_property_append_usec,         "t", offsetof(Service, start_limit.interval)         },
-        { "StartLimitBurst",        bus_property_append_uint32,       "u", offsetof(Service, start_limit.burst)            },
-        { "StartLimitAction",       bus_service_append_start_limit_action,"s", offsetof(Service, start_limit_action), false, bus_service_set_start_limit_action},
-        BUS_EXEC_COMMAND_PROPERTY("ExecStartPre",  offsetof(Service, exec_command[SERVICE_EXEC_START_PRE]),  true ),
-        BUS_EXEC_COMMAND_PROPERTY("ExecStart",     offsetof(Service, exec_command[SERVICE_EXEC_START]),      true ),
-        BUS_EXEC_COMMAND_PROPERTY("ExecStartPost", offsetof(Service, exec_command[SERVICE_EXEC_START_POST]), true ),
-        BUS_EXEC_COMMAND_PROPERTY("ExecReload",    offsetof(Service, exec_command[SERVICE_EXEC_RELOAD]),     true ),
-        BUS_EXEC_COMMAND_PROPERTY("ExecStop",      offsetof(Service, exec_command[SERVICE_EXEC_STOP]),       true ),
-        BUS_EXEC_COMMAND_PROPERTY("ExecStopPost",  offsetof(Service, exec_command[SERVICE_EXEC_STOP_POST]),  true ),
-        { "PermissionsStartOnly",   bus_property_append_bool,         "b", offsetof(Service, permissions_start_only)       },
-        { "RootDirectoryStartOnly", bus_property_append_bool,         "b", offsetof(Service, root_directory_start_only)    },
-        { "RemainAfterExit",        bus_property_append_bool,         "b", offsetof(Service, remain_after_exit)            },
-        { "GuessMainPID",           bus_property_append_bool,         "b", offsetof(Service, guess_main_pid)               },
-        { "MainPID",                bus_property_append_pid,          "u", offsetof(Service, main_pid)                     },
-        { "ControlPID",             bus_property_append_pid,          "u", offsetof(Service, control_pid)                  },
-        { "BusName",                bus_property_append_string,       "s", offsetof(Service, bus_name),               true },
-        { "StatusText",             bus_property_append_string,       "s", offsetof(Service, status_text),            true },
-        { "Result",                 bus_service_append_service_result,"s", offsetof(Service, result)                       },
-        {}
+const char* const bus_service_changing_properties[] = {
+        "ExecMainStartTimestamp",
+        "ExecMainStartTimestampMonotonic",
+        "ExecMainExitTimestamp",
+        "ExecMainExitTimestampMonotonic",
+        "ExecMainPID",
+        "ExecMainCode",
+        "ExecMainStatus",
+        "MainPID",
+        "ControlPID",
+        "StatusText",
+        "Result",
+        NULL
 };
 
-DBusHandlerResult bus_service_message_handler(Unit *u, DBusConnection *connection, DBusMessage *message) {
-        Service *s = SERVICE(u);
-
-        const BusBoundProperties bps[] = {
-                { "org.freedesktop.systemd1.Unit",    bus_unit_properties,             u },
-                { "org.freedesktop.systemd1.Service", bus_unit_cgroup_properties,      u },
-                { "org.freedesktop.systemd1.Service", bus_service_properties,          s },
-                { "org.freedesktop.systemd1.Service", bus_exec_context_properties,     &s->exec_context },
-                { "org.freedesktop.systemd1.Service", bus_kill_context_properties,     &s->kill_context },
-                { "org.freedesktop.systemd1.Service", bus_cgroup_context_properties,   &s->cgroup_context },
-                { "org.freedesktop.systemd1.Service", bus_exec_main_status_properties, &s->main_exec_status },
-                {}
-        };
-
-        SELINUX_UNIT_ACCESS_CHECK(u, connection, message, "status");
-
-        return bus_default_message_handler(connection, message, INTROSPECTION, INTERFACES_LIST, bps);
-}
-
 static int bus_service_set_transient_property(
                 Service *s,
                 const char *name,
-                DBusMessageIter *i,
+                sd_bus_message *message,
                 UnitSetPropertiesMode mode,
-                DBusError *error) {
+                sd_bus_error *error) {
 
         int r;
 
-        assert(name);
         assert(s);
-        assert(i);
+        assert(name);
+        assert(message);
 
         if (streq(name, "RemainAfterExit")) {
-                if (dbus_message_iter_get_arg_type(i) != DBUS_TYPE_BOOLEAN)
-                        return -EINVAL;
+                int b;
 
-                if (mode != UNIT_CHECK) {
-                        dbus_bool_t b;
-
-                        dbus_message_iter_get_basic(i, &b);
+                r = sd_bus_message_read(message, "b", &b);
+                if (r < 0)
+                        return r;
 
+                if (mode != UNIT_CHECK) {
                         s->remain_after_exit = b;
                         unit_write_drop_in_private_format(UNIT(s), mode, name, "RemainAfterExit=%s\n", yes_no(b));
                 }
@@ -196,38 +112,35 @@ static int bus_service_set_transient_property(
                 return 1;
 
         } else if (streq(name, "ExecStart")) {
-                DBusMessageIter sub;
                 unsigned n = 0;
 
-                if (dbus_message_iter_get_arg_type(i) != DBUS_TYPE_ARRAY ||
-                    dbus_message_iter_get_element_type(i) != DBUS_TYPE_STRUCT)
-                        return -EINVAL;
+                r = sd_bus_message_enter_container(message, 'a', "(sasb)");
+                if (r < 0)
+                        return r;
 
-                dbus_message_iter_recurse(i, &sub);
-                while (dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_STRUCT) {
+                while ((r = sd_bus_message_enter_container(message, 'r', "sasb")) > 0) {
                         _cleanup_strv_free_ char **argv = NULL;
-                        DBusMessageIter sub2;
-                        dbus_bool_t ignore;
                         const char *path;
+                        int b;
 
-                        dbus_message_iter_recurse(&sub, &sub2);
-
-                        if (bus_iter_get_basic_and_next(&sub2, DBUS_TYPE_STRING, &path, true) < 0)
-                                return -EINVAL;
+                        r = sd_bus_message_read(message, "s", &path);
+                        if (r < 0)
+                                return r;
 
-                        if (!path_is_absolute(path)) {
-                                dbus_set_error(error, DBUS_ERROR_INVALID_ARGS, "Path %s is not absolute.", path);
-                                return -EINVAL;
-                        }
+                        if (!path_is_absolute(path))
+                                return sd_bus_error_set_errnof(error, EINVAL, "Path %s is not absolute.", path);
 
-                        r = bus_parse_strv_iter(&sub2, &argv);
+                        r = sd_bus_message_read_strv(message, &argv);
                         if (r < 0)
                                 return r;
 
-                        dbus_message_iter_next(&sub2);
+                        r = sd_bus_message_read(message, "b", &b);
+                        if (r < 0)
+                                return r;
 
-                        if (bus_iter_get_basic_and_next(&sub2, DBUS_TYPE_BOOLEAN, &ignore, false) < 0)
-                                return -EINVAL;
+                        r = sd_bus_message_exit_container(message);
+                        if (r < 0)
+                                return r;
 
                         if (mode != UNIT_CHECK) {
                                 ExecCommand *c;
@@ -245,15 +158,16 @@ static int bus_service_set_transient_property(
                                 c->argv = argv;
                                 argv = NULL;
 
-                                c->ignore = ignore;
+                                c->ignore = b;
 
                                 path_kill_slashes(c->path);
                                 exec_command_append_list(&s->exec_command[SERVICE_EXEC_START], c);
                         }
 
                         n++;
-                        dbus_message_iter_next(&sub);
                 }
+                if (r < 0)
+                        return r;
 
                 if (mode != UNIT_CHECK) {
                         _cleanup_free_ char *buf = NULL;
@@ -298,29 +212,29 @@ static int bus_service_set_transient_property(
 int bus_service_set_property(
                 Unit *u,
                 const char *name,
-                DBusMessageIter *i,
+                sd_bus_message *message,
                 UnitSetPropertiesMode mode,
-                DBusError *error) {
+                sd_bus_error *error) {
 
         Service *s = SERVICE(u);
         int r;
 
+        assert(s);
         assert(name);
-        assert(u);
-        assert(i);
+        assert(message);
 
-        r = bus_cgroup_set_property(u, &s->cgroup_context, name, i, mode, error);
+        r = bus_cgroup_set_property(u, &s->cgroup_context, name, message, mode, error);
         if (r != 0)
                 return r;
 
         if (u->transient && u->load_state == UNIT_STUB) {
                 /* This is a transient unit, let's load a little more */
 
-                r = bus_service_set_transient_property(s, name, i, mode, error);
+                r = bus_service_set_transient_property(s, name, message, mode, error);
                 if (r != 0)
                         return r;
 
-                r = bus_kill_context_set_transient_property(u, &s->kill_context, name, i, mode, error);
+                r = bus_kill_context_set_transient_property(u, &s->kill_context, name, message, mode, error);
                 if (r != 0)
                         return r;
         }