[PATCH v3 3/4] dbus: Add disconnect watch support

Allow caller to monitor the disconnect status of a service. --- ell/dbus-private.h | 35 ++++++++++ ell/dbus.c | 195 +++++++++++++++++++++++++++++++++++++++++++++++++++++ ell/dbus.h | 9 +++ 3 files changed, 239 insertions(+) diff --git a/ell/dbus-private.h b/ell/dbus-private.h index 9987294..cbde2fd 100644 --- a/ell/dbus-private.h +++ b/ell/dbus-private.h @@ -212,3 +212,38 @@ int _dbus_kernel_remove_match(int fd, uint64_t cookie); uint8_t _dbus_get_version(struct l_dbus *dbus); int _dbus_get_fd(struct l_dbus *dbus); + +struct _dbus_filter_data { + struct l_dbus *dbus; + l_dbus_message_func_t handle_func; + l_dbus_watch_func_t connect_func; + l_dbus_watch_func_t disconnect_func; + char *sender; + char *path; + char *interface; + char *member; + char *argument; + void *user_data; + l_dbus_destroy_func_t destroy_func; +}; + +typedef void (*l_dbus_match_func_t) (struct _dbus_filter_data *data, + l_dbus_message_func_t filter); + +void _dbus_message_filter_dispatcher(struct l_dbus_message *message, + void *user_data); +void _dbus1_format_rule(struct _dbus_filter_data *data, char *rule, + size_t size); +struct _dbus_filter_data *_dbus1_filter_data_get(struct l_dbus *dbus, + l_dbus_message_func_t filter, + const char *sender, + const char *path, + const char *interface, + const char *member, + const char *argument, + l_dbus_watch_func_t disconnect_func, + void *user_data, + l_dbus_destroy_func_t destroy, + l_dbus_match_func_t match); +void _dbus1_filter_data_destroy(void *user_data, l_dbus_match_func_t match); +void _dbus1_service_filter(struct l_dbus_message *message, void *user_data); diff --git a/ell/dbus.c b/ell/dbus.c index c10e0ed..8596449 100644 --- a/ell/dbus.c +++ b/ell/dbus.c @@ -53,6 +53,8 @@ #define DBUS_INTERFACE_INTROSPECTABLE "org.freedesktop.DBus.Introspectable" #define DBUS_INTERFACE_PROPERTIES "org.freedesktop.DBus.Properties" +#define DBUS_MAXIMUM_MATCH_RULE_LENGTH 1024 + enum auth_state { WAITING_FOR_OK, WAITING_FOR_AGREE_UNIX_FD, @@ -1253,3 +1255,196 @@ static void _dbus_bus_remove_match(struct l_dbus *dbus, const char *rule) { send_match(dbus, rule, "RemoveMatch"); } + +void _dbus1_format_rule(struct _dbus_filter_data *data, char *rule, + size_t size) +{ + int offset; + + offset = snprintf(rule, size, "type='signal'"); + + if (data->sender) + offset += snprintf(rule + offset, size - offset, + ",sender='%s'", data->sender); + if (data->path) + offset += snprintf(rule + offset, size - offset, + ",path='%s'", data->path); + if (data->interface) + offset += snprintf(rule + offset, size - offset, + ",interface='%s'", data->interface); + if (data->member) + offset += snprintf(rule + offset, size - offset, + ",member='%s'", data->member); + if (data->argument) + snprintf(rule + offset, size - offset, + ",arg0='%s'", data->argument); +} + +static void add_match(struct _dbus_filter_data *data, + l_dbus_message_func_t filter) +{ + char rule[DBUS_MAXIMUM_MATCH_RULE_LENGTH]; + + _dbus1_format_rule(data, rule, sizeof(rule)); + + _dbus_bus_add_match(data->dbus, rule); + + data->handle_func = filter; +} + +static void remove_match(struct _dbus_filter_data *data, + l_dbus_message_func_t filter) +{ + char rule[DBUS_MAXIMUM_MATCH_RULE_LENGTH]; + + _dbus1_format_rule(data, rule, sizeof(rule)); + + _dbus_bus_remove_match(data->dbus, rule); +} + +struct _dbus_filter_data *_dbus1_filter_data_get(struct l_dbus *dbus, + l_dbus_message_func_t filter, + const char *sender, + const char *path, + const char *interface, + const char *member, + const char *argument, + l_dbus_watch_func_t disconnect_func, + void *user_data, + l_dbus_destroy_func_t destroy, + l_dbus_match_func_t add_match) +{ + struct _dbus_filter_data *data; + + data = l_new(struct _dbus_filter_data, 1); + + data->dbus = dbus; + data->handle_func = filter; + data->disconnect_func = disconnect_func; + data->sender = l_strdup(sender); + data->path = l_strdup(path); + data->interface = l_strdup(interface); + data->member = l_strdup(member); + data->argument = l_strdup(argument); + data->user_data = user_data; + data->destroy_func = destroy; + + add_match(data, filter); + + return data; +} + +void _dbus1_filter_data_destroy(void *user_data, + l_dbus_match_func_t remove_match) +{ + struct _dbus_filter_data *data = user_data; + + remove_match(data, NULL); + + l_free(data->sender); + l_free(data->path); + l_free(data->interface); + l_free(data->member); + l_free(data->argument); + + if (data->destroy_func) + data->destroy_func(data->user_data); + + l_free(data); +} + +static void filter_data_destroy(void *user_data) +{ + _dbus1_filter_data_destroy(user_data, remove_match); +} + +void _dbus_message_filter_dispatcher(struct l_dbus_message *message, + void *user_data) +{ + struct _dbus_filter_data *data = user_data; + const char *sender, *path, *iface, *member; + + if (_dbus_message_get_type(message) != DBUS_MESSAGE_TYPE_SIGNAL) + return; + + sender = l_dbus_message_get_sender(message); + if (!sender) + return; + + if (data->sender && strcmp(sender, data->sender)) + return; + + path = l_dbus_message_get_path(message); + if (data->path && strcmp(path, data->path)) + return; + + iface = l_dbus_message_get_interface(message); + if (data->interface && strcmp(iface, data->interface)) + return; + + member = l_dbus_message_get_member(message); + if (data->member && strcmp(member, data->member)) + return; + + if (data->handle_func) + data->handle_func(message, data); +} + +void _dbus1_service_filter(struct l_dbus_message *message, void *user_data) +{ + struct _dbus_filter_data *data = user_data; + char *name, *old, *new; + + if (!l_dbus_message_get_arguments(message, "sss", + &name, &old, &new)) + return; + + if (strcmp(name, data->argument)) + return; + + if (*new == '\0') { + if (data->disconnect_func) + data->disconnect_func(data->dbus, data->user_data); + } +} + +static unsigned int l_dbus_add_service_watch(struct l_dbus *dbus, + const char *name, + l_dbus_watch_func_t disconnect_func, + void *user_data, + l_dbus_destroy_func_t destroy) +{ + struct _dbus_filter_data *data; + + if (!name) + return 0; + + data = _dbus1_filter_data_get(dbus, _dbus1_service_filter, + DBUS_SERVICE_DBUS, DBUS_PATH_DBUS, + DBUS_INTERFACE_DBUS, "NameOwnerChanged", + name, + disconnect_func, + user_data, + destroy, + add_match); + if (!data) + return 0; + + return l_dbus_register(dbus, _dbus_message_filter_dispatcher, data, + filter_data_destroy); +} + +LIB_EXPORT unsigned int l_dbus_add_disconnect_watch(struct l_dbus *dbus, + const char *name, + l_dbus_watch_func_t disconnect_func, + void *user_data, + l_dbus_destroy_func_t destroy) +{ + return l_dbus_add_service_watch(dbus, name, disconnect_func, + user_data, destroy); +} + +LIB_EXPORT bool l_dbus_remove_watch(struct l_dbus *dbus, unsigned int id) +{ + return l_dbus_unregister(dbus, id); +} diff --git a/ell/dbus.h b/ell/dbus.h index a6ad109..39f926b 100644 --- a/ell/dbus.h +++ b/ell/dbus.h @@ -48,6 +48,8 @@ typedef void (*l_dbus_debug_func_t) (const char *str, void *user_data); typedef void (*l_dbus_destroy_func_t) (void *user_data); typedef void (*l_dbus_interface_setup_func_t) (struct l_dbus_interface *); +typedef void (*l_dbus_watch_func_t) (struct l_dbus *dbus, void *user_data); + struct l_dbus *l_dbus_new(const char *address); struct l_dbus *l_dbus_new_default(enum l_dbus_bus bus); void l_dbus_destroy(struct l_dbus *dbus); @@ -196,6 +198,13 @@ bool l_dbus_register_interface(struct l_dbus *dbus, l_dbus_destroy_func_t destroy); bool l_dbus_unregister_interface(struct l_dbus *dbus, const char *path, const char *interface); +unsigned int l_dbus_add_disconnect_watch(struct l_dbus *dbus, + const char *name, + l_dbus_watch_func_t disconnect_func, + void *user_data, + l_dbus_destroy_func_t destroy); +bool l_dbus_remove_watch(struct l_dbus *dbus, unsigned int id); + #ifdef __cplusplus } #endif -- 2.1.0