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-rw-r--r--gdbus/watch.c748
1 files changed, 748 insertions, 0 deletions
diff --git a/gdbus/watch.c b/gdbus/watch.c
new file mode 100644
index 0000000..fba58c3
--- /dev/null
+++ b/gdbus/watch.c
@@ -0,0 +1,748 @@
+/*
+ *
+ * D-Bus helper library
+ *
+ * Copyright (C) 2004-2011 Marcel Holtmann <marcel@holtmann.org>
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <string.h>
+
+#include <glib.h>
+#include <dbus/dbus.h>
+
+#include "gdbus.h"
+
+#define info(fmt...)
+#define error(fmt...)
+#define debug(fmt...)
+
+static DBusHandlerResult message_filter(DBusConnection *connection,
+ DBusMessage *message, void *user_data);
+
+static guint listener_id = 0;
+static GSList *listeners = NULL;
+
+struct service_data {
+ DBusConnection *conn;
+ DBusPendingCall *call;
+ char *name;
+ const char *owner;
+ guint id;
+ struct filter_callback *callback;
+};
+
+struct filter_callback {
+ GDBusWatchFunction conn_func;
+ GDBusWatchFunction disc_func;
+ GDBusSignalFunction signal_func;
+ GDBusDestroyFunction destroy_func;
+ struct service_data *data;
+ void *user_data;
+ guint id;
+};
+
+struct filter_data {
+ DBusConnection *connection;
+ DBusHandleMessageFunction handle_func;
+ char *name;
+ char *owner;
+ char *path;
+ char *interface;
+ char *member;
+ char *argument;
+ GSList *callbacks;
+ GSList *processed;
+ guint name_watch;
+ gboolean lock;
+ gboolean registered;
+};
+
+static struct filter_data *filter_data_find(DBusConnection *connection,
+ const char *name,
+ const char *owner,
+ const char *path,
+ const char *interface,
+ const char *member,
+ const char *argument)
+{
+ GSList *current;
+
+ for (current = listeners;
+ current != NULL; current = current->next) {
+ struct filter_data *data = current->data;
+
+ if (connection != data->connection)
+ continue;
+
+ if (name && data->name &&
+ g_str_equal(name, data->name) == FALSE)
+ continue;
+
+ if (owner && data->owner &&
+ g_str_equal(owner, data->owner) == FALSE)
+ continue;
+
+ if (path && data->path &&
+ g_str_equal(path, data->path) == FALSE)
+ continue;
+
+ if (interface && data->interface &&
+ g_str_equal(interface, data->interface) == FALSE)
+ continue;
+
+ if (member && data->member &&
+ g_str_equal(member, data->member) == FALSE)
+ continue;
+
+ if (argument && data->argument &&
+ g_str_equal(argument, data->argument) == FALSE)
+ continue;
+
+ return data;
+ }
+
+ return NULL;
+}
+
+static void format_rule(struct filter_data *data, char *rule, size_t size)
+{
+ const char *sender;
+ int offset;
+
+ offset = snprintf(rule, size, "type='signal'");
+ sender = data->name ? : data->owner;
+
+ if (sender)
+ offset += snprintf(rule + offset, size - offset,
+ ",sender='%s'", 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 gboolean add_match(struct filter_data *data,
+ DBusHandleMessageFunction filter)
+{
+ DBusError err;
+ char rule[DBUS_MAXIMUM_MATCH_RULE_LENGTH];
+
+ format_rule(data, rule, sizeof(rule));
+ dbus_error_init(&err);
+
+ dbus_bus_add_match(data->connection, rule, &err);
+ if (dbus_error_is_set(&err)) {
+ error("Adding match rule \"%s\" failed: %s", rule,
+ err.message);
+ dbus_error_free(&err);
+ return FALSE;
+ }
+
+ data->handle_func = filter;
+ data->registered = TRUE;
+
+ return TRUE;
+}
+
+static gboolean remove_match(struct filter_data *data)
+{
+ DBusError err;
+ char rule[DBUS_MAXIMUM_MATCH_RULE_LENGTH];
+
+ format_rule(data, rule, sizeof(rule));
+
+ dbus_error_init(&err);
+
+ dbus_bus_remove_match(data->connection, rule, &err);
+ if (dbus_error_is_set(&err)) {
+ error("Removing owner match rule for %s failed: %s",
+ rule, err.message);
+ dbus_error_free(&err);
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+static struct filter_data *filter_data_get(DBusConnection *connection,
+ DBusHandleMessageFunction filter,
+ const char *sender,
+ const char *path,
+ const char *interface,
+ const char *member,
+ const char *argument)
+{
+ struct filter_data *data;
+ const char *name = NULL, *owner = NULL;
+
+ if (filter_data_find(connection, NULL, NULL, NULL, NULL, NULL, NULL) == NULL) {
+ if (!dbus_connection_add_filter(connection,
+ message_filter, NULL, NULL)) {
+ error("dbus_connection_add_filter() failed");
+ return NULL;
+ }
+ }
+
+ if (sender == NULL)
+ goto proceed;
+
+ if (sender[0] == ':')
+ owner = sender;
+ else
+ name = sender;
+
+proceed:
+ data = filter_data_find(connection, name, owner, path, interface,
+ member, argument);
+ if (data)
+ return data;
+
+ data = g_new0(struct filter_data, 1);
+
+ data->connection = dbus_connection_ref(connection);
+ data->name = name ? g_strdup(name) : NULL;
+ data->owner = owner ? g_strdup(owner) : NULL;
+ data->path = g_strdup(path);
+ data->interface = g_strdup(interface);
+ data->member = g_strdup(member);
+ data->argument = g_strdup(argument);
+
+ if (!add_match(data, filter)) {
+ g_free(data);
+ return NULL;
+ }
+
+ listeners = g_slist_append(listeners, data);
+
+ return data;
+}
+
+static struct filter_callback *filter_data_find_callback(
+ struct filter_data *data,
+ guint id)
+{
+ GSList *l;
+
+ for (l = data->callbacks; l; l = l->next) {
+ struct filter_callback *cb = l->data;
+ if (cb->id == id)
+ return cb;
+ }
+ for (l = data->processed; l; l = l->next) {
+ struct filter_callback *cb = l->data;
+ if (cb->id == id)
+ return cb;
+ }
+
+ return NULL;
+}
+
+static void filter_data_free(struct filter_data *data)
+{
+ GSList *l;
+
+ for (l = data->callbacks; l != NULL; l = l->next)
+ g_free(l->data);
+
+ g_slist_free(data->callbacks);
+ g_dbus_remove_watch(data->connection, data->name_watch);
+ g_free(data->name);
+ g_free(data->owner);
+ g_free(data->path);
+ g_free(data->interface);
+ g_free(data->member);
+ g_free(data->argument);
+ dbus_connection_unref(data->connection);
+ g_free(data);
+}
+
+static void filter_data_call_and_free(struct filter_data *data)
+{
+ GSList *l;
+
+ for (l = data->callbacks; l != NULL; l = l->next) {
+ struct filter_callback *cb = l->data;
+ if (cb->disc_func)
+ cb->disc_func(data->connection, cb->user_data);
+ if (cb->destroy_func)
+ cb->destroy_func(cb->user_data);
+ g_free(cb);
+ }
+
+ filter_data_free(data);
+}
+
+static struct filter_callback *filter_data_add_callback(
+ struct filter_data *data,
+ GDBusWatchFunction connect,
+ GDBusWatchFunction disconnect,
+ GDBusSignalFunction signal,
+ GDBusDestroyFunction destroy,
+ void *user_data)
+{
+ struct filter_callback *cb = NULL;
+
+ cb = g_new0(struct filter_callback, 1);
+
+ cb->conn_func = connect;
+ cb->disc_func = disconnect;
+ cb->signal_func = signal;
+ cb->destroy_func = destroy;
+ cb->user_data = user_data;
+ cb->id = ++listener_id;
+
+ if (data->lock)
+ data->processed = g_slist_append(data->processed, cb);
+ else
+ data->callbacks = g_slist_append(data->callbacks, cb);
+
+ return cb;
+}
+
+static void service_data_free(struct service_data *data)
+{
+ struct filter_callback *callback = data->callback;
+
+ dbus_connection_unref(data->conn);
+
+ if (data->call)
+ dbus_pending_call_unref(data->call);
+
+ if (data->id)
+ g_source_remove(data->id);
+
+ g_free(data->name);
+ g_free(data);
+
+ callback->data = NULL;
+}
+
+static gboolean filter_data_remove_callback(struct filter_data *data,
+ struct filter_callback *cb)
+{
+ DBusConnection *connection;
+
+ data->callbacks = g_slist_remove(data->callbacks, cb);
+ data->processed = g_slist_remove(data->processed, cb);
+
+ /* Cancel pending operations */
+ if (cb->data) {
+ if (cb->data->call)
+ dbus_pending_call_cancel(cb->data->call);
+ service_data_free(cb->data);
+ }
+
+ if (cb->destroy_func)
+ cb->destroy_func(cb->user_data);
+
+ g_free(cb);
+
+ /* Don't remove the filter if other callbacks exist or data is lock
+ * processing callbacks */
+ if (data->callbacks || data->lock)
+ return TRUE;
+
+ if (data->registered && !remove_match(data))
+ return FALSE;
+
+ connection = dbus_connection_ref(data->connection);
+ listeners = g_slist_remove(listeners, data);
+ filter_data_free(data);
+
+ /* Remove filter if there are no listeners left for the connection */
+ data = filter_data_find(connection, NULL, NULL, NULL, NULL, NULL,
+ NULL);
+ if (data == NULL)
+ dbus_connection_remove_filter(connection, message_filter,
+ NULL);
+
+ dbus_connection_unref(connection);
+
+ return TRUE;
+}
+
+static DBusHandlerResult signal_filter(DBusConnection *connection,
+ DBusMessage *message, void *user_data)
+{
+ struct filter_data *data = user_data;
+ struct filter_callback *cb;
+
+ while (data->callbacks) {
+ cb = data->callbacks->data;
+
+ if (cb->signal_func && !cb->signal_func(connection, message,
+ cb->user_data)) {
+ filter_data_remove_callback(data, cb);
+ continue;
+ }
+
+ /* Check if the watch was removed/freed by the callback
+ * function */
+ if (!g_slist_find(data->callbacks, cb))
+ continue;
+
+ data->callbacks = g_slist_remove(data->callbacks, cb);
+ data->processed = g_slist_append(data->processed, cb);
+ }
+
+ return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+static void update_name_cache(const char *name, const char *owner)
+{
+ GSList *l;
+
+ for (l = listeners; l != NULL; l = l->next) {
+ struct filter_data *data = l->data;
+
+ if (g_strcmp0(data->name, name) != 0)
+ continue;
+
+ g_free(data->owner);
+ data->owner = g_strdup(owner);
+ }
+}
+
+static const char *check_name_cache(const char *name)
+{
+ GSList *l;
+
+ for (l = listeners; l != NULL; l = l->next) {
+ struct filter_data *data = l->data;
+
+ if (g_strcmp0(data->name, name) != 0)
+ continue;
+
+ return data->owner;
+ }
+
+ return NULL;
+}
+
+static DBusHandlerResult service_filter(DBusConnection *connection,
+ DBusMessage *message, void *user_data)
+{
+ struct filter_data *data = user_data;
+ struct filter_callback *cb;
+ char *name, *old, *new;
+
+ if (!dbus_message_get_args(message, NULL,
+ DBUS_TYPE_STRING, &name,
+ DBUS_TYPE_STRING, &old,
+ DBUS_TYPE_STRING, &new,
+ DBUS_TYPE_INVALID)) {
+ error("Invalid arguments for NameOwnerChanged signal");
+ return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+ }
+
+ update_name_cache(name, new);
+
+ while (data->callbacks) {
+ cb = data->callbacks->data;
+
+ if (*new == '\0') {
+ if (cb->disc_func)
+ cb->disc_func(connection, cb->user_data);
+ } else {
+ if (cb->conn_func)
+ cb->conn_func(connection, cb->user_data);
+ }
+
+ /* Check if the watch was removed/freed by the callback
+ * function */
+ if (!g_slist_find(data->callbacks, cb))
+ continue;
+
+ /* Only auto remove if it is a bus name watch */
+ if (data->argument[0] == ':' &&
+ (cb->conn_func == NULL || cb->disc_func == NULL)) {
+ filter_data_remove_callback(data, cb);
+ continue;
+ }
+
+ data->callbacks = g_slist_remove(data->callbacks, cb);
+ data->processed = g_slist_append(data->processed, cb);
+ }
+
+ return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+
+static DBusHandlerResult message_filter(DBusConnection *connection,
+ DBusMessage *message, void *user_data)
+{
+ struct filter_data *data;
+ const char *sender, *path, *iface, *member, *arg = NULL;
+
+ /* Only filter signals */
+ if (dbus_message_get_type(message) != DBUS_MESSAGE_TYPE_SIGNAL)
+ return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+
+ sender = dbus_message_get_sender(message);
+ path = dbus_message_get_path(message);
+ iface = dbus_message_get_interface(message);
+ member = dbus_message_get_member(message);
+ dbus_message_get_args(message, NULL, DBUS_TYPE_STRING, &arg, DBUS_TYPE_INVALID);
+
+ /* Sender is always bus name */
+ data = filter_data_find(connection, NULL, sender, path, iface, member,
+ arg);
+ if (data == NULL) {
+ error("Got %s.%s signal which has no listeners", iface, member);
+ return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+ }
+
+ if (data->handle_func) {
+ data->lock = TRUE;
+
+ data->handle_func(connection, message, data);
+
+ data->callbacks = data->processed;
+ data->processed = NULL;
+ data->lock = FALSE;
+ }
+
+ if (data->callbacks)
+ return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+
+ remove_match(data);
+
+ listeners = g_slist_remove(listeners, data);
+ filter_data_free(data);
+
+ /* Remove filter if there no listener left for the connection */
+ data = filter_data_find(connection, NULL, NULL, NULL, NULL, NULL,
+ NULL);
+ if (data == NULL)
+ dbus_connection_remove_filter(connection, message_filter,
+ NULL);
+
+ return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+static gboolean update_service(void *user_data)
+{
+ struct service_data *data = user_data;
+ struct filter_callback *cb = data->callback;
+
+ update_name_cache(data->name, data->owner);
+ if (cb->conn_func)
+ cb->conn_func(data->conn, cb->user_data);
+
+ service_data_free(data);
+
+ return FALSE;
+}
+
+static void service_reply(DBusPendingCall *call, void *user_data)
+{
+ struct service_data *data = user_data;
+ DBusMessage *reply;
+ DBusError err;
+
+ reply = dbus_pending_call_steal_reply(call);
+ if (reply == NULL)
+ return;
+
+ dbus_error_init(&err);
+
+ if (dbus_set_error_from_message(&err, reply))
+ goto fail;
+
+ if (dbus_message_get_args(reply, &err,
+ DBUS_TYPE_STRING, &data->owner,
+ DBUS_TYPE_INVALID) == FALSE)
+ goto fail;
+
+ update_service(data);
+
+ goto done;
+
+fail:
+ error("%s", err.message);
+ dbus_error_free(&err);
+ service_data_free(data);
+done:
+ dbus_message_unref(reply);
+}
+
+static void check_service(DBusConnection *connection,
+ const char *name,
+ struct filter_callback *callback)
+{
+ DBusMessage *message;
+ struct service_data *data;
+
+ data = g_try_malloc0(sizeof(*data));
+ if (data == NULL) {
+ error("Can't allocate data structure");
+ return;
+ }
+
+ data->conn = dbus_connection_ref(connection);
+ data->name = g_strdup(name);
+ data->callback = callback;
+ callback->data = data;
+
+ data->owner = check_name_cache(name);
+ if (data->owner != NULL) {
+ data->id = g_idle_add(update_service, data);
+ return;
+ }
+
+ message = dbus_message_new_method_call(DBUS_SERVICE_DBUS,
+ DBUS_PATH_DBUS, DBUS_INTERFACE_DBUS, "GetNameOwner");
+ if (message == NULL) {
+ error("Can't allocate new message");
+ g_free(data);
+ return;
+ }
+
+ dbus_message_append_args(message, DBUS_TYPE_STRING, &name,
+ DBUS_TYPE_INVALID);
+
+ if (dbus_connection_send_with_reply(connection, message,
+ &data->call, -1) == FALSE) {
+ error("Failed to execute method call");
+ g_free(data);
+ goto done;
+ }
+
+ if (data->call == NULL) {
+ error("D-Bus connection not available");
+ g_free(data);
+ goto done;
+ }
+
+ dbus_pending_call_set_notify(data->call, service_reply, data, NULL);
+
+done:
+ dbus_message_unref(message);
+}
+
+guint g_dbus_add_service_watch(DBusConnection *connection, const char *name,
+ GDBusWatchFunction connect,
+ GDBusWatchFunction disconnect,
+ void *user_data, GDBusDestroyFunction destroy)
+{
+ struct filter_data *data;
+ struct filter_callback *cb;
+
+ if (name == NULL)
+ return 0;
+
+ data = filter_data_get(connection, service_filter, NULL, NULL,
+ DBUS_INTERFACE_DBUS, "NameOwnerChanged",
+ name);
+ if (data == NULL)
+ return 0;
+
+ cb = filter_data_add_callback(data, connect, disconnect, NULL, NULL,
+ user_data);
+ if (cb == NULL)
+ return 0;
+
+ if (connect)
+ check_service(connection, name, cb);
+
+ return cb->id;
+}
+
+guint g_dbus_add_disconnect_watch(DBusConnection *connection, const char *name,
+ GDBusWatchFunction func,
+ void *user_data, GDBusDestroyFunction destroy)
+{
+ return g_dbus_add_service_watch(connection, name, NULL, func,
+ user_data, destroy);
+}
+
+guint g_dbus_add_signal_watch(DBusConnection *connection,
+ const char *sender, const char *path,
+ const char *interface, const char *member,
+ GDBusSignalFunction function, void *user_data,
+ GDBusDestroyFunction destroy)
+{
+ struct filter_data *data;
+ struct filter_callback *cb;
+
+ data = filter_data_get(connection, signal_filter, sender, path,
+ interface, member, NULL);
+ if (data == NULL)
+ return 0;
+
+ cb = filter_data_add_callback(data, NULL, NULL, function, destroy,
+ user_data);
+ if (cb == NULL)
+ return 0;
+
+ if (data->name != NULL && data->name_watch == 0)
+ data->name_watch = g_dbus_add_service_watch(connection,
+ data->name, NULL,
+ NULL, NULL, NULL);
+
+ return cb->id;
+}
+
+gboolean g_dbus_remove_watch(DBusConnection *connection, guint id)
+{
+ struct filter_data *data;
+ struct filter_callback *cb;
+ GSList *ldata;
+
+ if (id == 0)
+ return FALSE;
+
+ for (ldata = listeners; ldata; ldata = ldata->next) {
+ data = ldata->data;
+
+ cb = filter_data_find_callback(data, id);
+ if (cb) {
+ filter_data_remove_callback(data, cb);
+ return TRUE;
+ }
+ }
+
+ return FALSE;
+}
+
+void g_dbus_remove_all_watches(DBusConnection *connection)
+{
+ struct filter_data *data;
+
+ while ((data = filter_data_find(connection, NULL, NULL, NULL, NULL,
+ NULL, NULL))) {
+ listeners = g_slist_remove(listeners, data);
+ filter_data_call_and_free(data);
+ }
+
+ dbus_connection_remove_filter(connection, message_filter, NULL);
+}
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