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fuchsia / third_party / glib / 7c909697db0f636692edc60954694187ffbd7260 / . / gio / gdbusconnection.c
blob: 42134a601b0580a969f9eb128b04a0c89ff61bc7 [file] [log] [blame]
/* GDBus - GLib D-Bus Library
*
* Copyright (C) 2008-2010 Red Hat, Inc.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
* Author: David Zeuthen <davidz@redhat.com>
*/
/*
* TODO for GDBus:
*
* - would be nice to expose GDBusAuthMechanism and an extension point
*
* - Need to rewrite GDBusAuth and rework GDBusAuthMechanism. In particular
* the mechanism VFuncs need to be able to set an error.
*
* - Need to document other mechanisms/sources for determining the D-Bus
* address of a well-known bus.
*
* - e.g. on Win32 we need code like from here
*
* http://cgit.freedesktop.org/~david/gdbus-standalone/tree/gdbus/gdbusaddress.c#n900
*
* that was never copied over here because it originally was copy-paste
* from the GPLv2 / AFL 2.1 libdbus sources.
*
* - on OS X we need to look in launchd for the address
*
* https://bugs.freedesktop.org/show_bug.cgi?id=14259
*
* - on X11 we need to look in a X11 property on the X server
* - (we can also just use dbus-launch(1) from the D-Bus
* distribution)
*
* - (ideally) this requires D-Bus spec work because none of
* this has never really been specced out properly (except
* the X11 bits)
*
* - Related to the above, we also need to be able to launch a message bus
* instance.... Since we don't want to write our own bus daemon we should
* launch dbus-daemon(1) (thus: Win32 and OS X need to bundle it)
*
* - probably want a G_DBUS_NONCE_TCP_TMPDIR environment variable
* to specify where the nonce is stored. This will allow people to use
* G_DBUS_NONCE_TCP_TMPDIR=/mnt/secure.company.server/dbus-nonce-dir
* to easily achieve secure RPC via nonce-tcp.
*
* - need to expose an extension point for resolving D-Bus address and
* turning them into GIOStream objects. This will allow us to implement
* e.g. X11 D-Bus transports without dlopen()'ing or linking against
* libX11 from libgio.
* - see g_dbus_address_connect() in gdbusaddress.c
*
* - would be cute to use kernel-specific APIs to resolve fds for
* debug output when using G_DBUS_DEBUG=message, e.g. in addition to
*
* fd 21: dev=8:1,mode=0100644,ino=1171231,uid=0,gid=0,rdev=0:0,size=234,atime=1273070640,mtime=1267126160,ctime=1267126160
*
* maybe we can show more information about what fd 21 really is.
* Ryan suggests looking in /proc/self/fd for clues / symlinks!
* Initial experiments on Linux 2.6 suggests that the symlink looks
* like this:
*
* 3 -> /proc/18068/fd
*
* e.g. not of much use.
*
* - GDBus High-Level docs
* - Proxy: properties, signals...
* - Connection: IOStream based, ::close, connection setup steps
* mainloop integration, threading
* - Differences from libdbus (extend "Migrating from")
* - the message handling thread
* - Using GVariant instead of GValue
* - Explain why the high-level API is a good thing and what
* kind of pitfalls it avoids
* - Export objects before claiming names
* - Talk about auto-starting services (cf. GBusNameWatcherFlags)
*/
#include "config.h"
#include <stdlib.h>
#include <string.h>
#include "gdbusauth.h"
#include "gdbusutils.h"
#include "gdbusaddress.h"
#include "gdbusmessage.h"
#include "gdbusconnection.h"
#include "gdbuserror.h"
#include "gioenumtypes.h"
#include "gdbusintrospection.h"
#include "gdbusmethodinvocation.h"
#include "gdbusprivate.h"
#include "gdbusauthobserver.h"
#include "ginitable.h"
#include "gasyncinitable.h"
#include "giostream.h"
#include "gasyncresult.h"
#include "gtask.h"
#include "gmarshal-internal.h"
#ifdef G_OS_UNIX
#include "gunixconnection.h"
#include "gunixfdmessage.h"
#endif
#include "glibintl.h"
#define G_DBUS_CONNECTION_FLAGS_ALL \
(G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT | \
G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER | \
G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_ALLOW_ANONYMOUS | \
G_DBUS_CONNECTION_FLAGS_MESSAGE_BUS_CONNECTION | \
G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING | \
G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_REQUIRE_SAME_USER)
/**
* GDBusConnection:
*
* The `GDBusConnection` type is used for D-Bus connections to remote
* peers such as a message buses.
*
* It is a low-level API that offers a lot of flexibility. For instance,
* it lets you establish a connection over any transport that can by represented
* as a [class@Gio.IOStream].
*
* This class is rarely used directly in D-Bus clients. If you are writing
* a D-Bus client, it is often easier to use the [func@Gio.bus_own_name],
* [func@Gio.bus_watch_name] or [func@Gio.DBusProxy.new_for_bus] APIs.
*
* As an exception to the usual GLib rule that a particular object must not
* be used by two threads at the same time, `GDBusConnection`s methods may be
* called from any thread. This is so that [func@Gio.bus_get] and
* [func@Gio.bus_get_sync] can safely return the same `GDBusConnection` when
* called from any thread.
*
* Most of the ways to obtain a `GDBusConnection` automatically initialize it
* (i.e. connect to D-Bus): for instance, [func@Gio.DBusConnection.new] and
* [func@Gio.bus_get], and the synchronous versions of those methods, give you
* an initialized connection. Language bindings for GIO should use
* [func@Gio.Initable.new] or [func@Gio.AsyncInitable.new_async], which also
* initialize the connection.
*
* If you construct an uninitialized `GDBusConnection`, such as via
* [ctor@GObject.Object.new], you must initialize it via [method@Gio.Initable.init] or
* [method@Gio.AsyncInitable.init_async] before using its methods or properties.
* Calling methods or accessing properties on a `GDBusConnection` that has not
* completed initialization successfully is considered to be invalid, and leads
* to undefined behaviour. In particular, if initialization fails with a
* `GError`, the only valid thing you can do with that `GDBusConnection` is to
* free it with [method@GObject.Object.unref].
*
* ## An example D-Bus server
*
* Here is an example for a D-Bus server:
* [gdbus-example-server.c](https://gitlab.gnome.org/GNOME/glib/-/blob/HEAD/gio/tests/gdbus-example-server.c)
*
* ## An example for exporting a subtree
*
* Here is an example for exporting a subtree:
* [gdbus-example-subtree.c](https://gitlab.gnome.org/GNOME/glib/-/blob/HEAD/gio/tests/gdbus-example-subtree.c)
*
* ## An example for file descriptor passing
*
* Here is an example for passing UNIX file descriptors:
* [gdbus-unix-fd-client.c](https://gitlab.gnome.org/GNOME/glib/-/blob/HEAD/gio/tests/gdbus-example-unix-fd-client.c)
*
* ## An example for exporting a GObject
*
* Here is an example for exporting a #GObject:
* [gdbus-example-export.c](https://gitlab.gnome.org/GNOME/glib/-/blob/HEAD/gio/tests/gdbus-example-export.c)
*
* Since: 2.26
*/
/* ---------------------------------------------------------------------------------------------------- */
typedef struct _GDBusConnectionClass GDBusConnectionClass;
/**
* GDBusConnectionClass:
* @closed: Signal class handler for the #GDBusConnection::closed signal.
*
* Class structure for #GDBusConnection.
*
* Since: 2.26
*/
struct _GDBusConnectionClass
{
/*< private >*/
GObjectClass parent_class;
/*< public >*/
/* Signals */
void (*closed) (GDBusConnection *connection,
gboolean remote_peer_vanished,
GError *error);
};
G_LOCK_DEFINE_STATIC (message_bus_lock);
static GWeakRef the_session_bus;
static GWeakRef the_system_bus;
/* Extra pseudo-member of GDBusSendMessageFlags.
* Set by initable_init() to indicate that despite not being initialized yet,
* enough of the only-valid-after-init members are set that we can send a
* message, and we're being called from its thread, so no memory barrier is
* required before accessing them.
*/
#define SEND_MESSAGE_FLAGS_INITIALIZING (1u << 31)
/* Same as SEND_MESSAGE_FLAGS_INITIALIZING, but in GDBusCallFlags */
#define CALL_FLAGS_INITIALIZING (1u << 31)
/* ---------------------------------------------------------------------------------------------------- */
typedef struct
{
GDestroyNotify callback;
gpointer user_data;
} CallDestroyNotifyData;
static gboolean
call_destroy_notify_data_in_idle (gpointer user_data)
{
CallDestroyNotifyData *data = user_data;
data->callback (data->user_data);
return FALSE;
}
static void
call_destroy_notify_data_free (CallDestroyNotifyData *data)
{
g_free (data);
}
/*
* call_destroy_notify: <internal>
* @context: (nullable): A #GMainContext or %NULL.
* @callback: (nullable): A #GDestroyNotify or %NULL.
* @user_data: Data to pass to @callback.
*
* Schedules @callback to run in @context.
*/
static void
call_destroy_notify (GMainContext *context,
GDestroyNotify callback,
gpointer user_data)
{
GSource *idle_source;
CallDestroyNotifyData *data;
if (callback == NULL)
return;
data = g_new0 (CallDestroyNotifyData, 1);
data->callback = callback;
data->user_data = user_data;
idle_source = g_idle_source_new ();
g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
g_source_set_callback (idle_source,
call_destroy_notify_data_in_idle,
data,
(GDestroyNotify) call_destroy_notify_data_free);
g_source_set_static_name (idle_source, "[gio] call_destroy_notify_data_in_idle");
g_source_attach (idle_source, context);
g_source_unref (idle_source);
}
/* ---------------------------------------------------------------------------------------------------- */
#ifdef G_OS_WIN32
#define CONNECTION_ENSURE_LOCK(obj) do { ; } while (FALSE)
#else
// TODO: for some reason this doesn't work on Windows
#define CONNECTION_ENSURE_LOCK(obj) do { \
if (G_UNLIKELY (g_mutex_trylock(&(obj)->lock))) \
{ \
g_assertion_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
"CONNECTION_ENSURE_LOCK: GDBusConnection object lock is not locked"); \
} \
} while (FALSE)
#endif
#define CONNECTION_LOCK(obj) do { \
g_mutex_lock (&(obj)->lock); \
} while (FALSE)
#define CONNECTION_UNLOCK(obj) do { \
g_mutex_unlock (&(obj)->lock); \
} while (FALSE)
/* Flags in connection->atomic_flags */
enum {
FLAG_INITIALIZED = 1 << 0,
FLAG_EXIT_ON_CLOSE = 1 << 1,
FLAG_CLOSED = 1 << 2
};
struct _GDBusConnection
{
/*< private >*/
GObject parent_instance;
/* ------------------------------------------------------------------------ */
/* -- General object state ------------------------------------------------ */
/* ------------------------------------------------------------------------ */
/* General-purpose lock for most fields */
GMutex lock;
/* A lock used in the init() method of the GInitable interface - see comments
* in initable_init() for why a separate lock is needed.
*
* If you need both @lock and @init_lock, you must take @init_lock first.
*/
GMutex init_lock;
/* Set (by loading the contents of /var/lib/dbus/machine-id) the first time
* someone calls org.freedesktop.DBus.Peer.GetMachineId(). Protected by @lock.
*/
gchar *machine_id;
/* The underlying stream used for communication
* Read-only after initable_init(), so it may be read if you either
* hold @init_lock or check for initialization first.
*/
GIOStream *stream;
/* The object used for authentication (if any).
* Read-only after initable_init(), so it may be read if you either
* hold @init_lock or check for initialization first.
*/
GDBusAuth *auth;
/* Last serial used. Protected by @lock. */
guint32 last_serial;
/* The object used to send/receive messages.
* Read-only after initable_init(), so it may be read if you either
* hold @init_lock or check for initialization first.
*/
GDBusWorker *worker;
/* If connected to a message bus, this contains the unique name assigned to
* us by the bus (e.g. ":1.42").
* Read-only after initable_init(), so it may be read if you either
* hold @init_lock or check for initialization first.
*/
gchar *bus_unique_name;
/* The GUID returned by the other side if we authenticated as a client or
* the GUID to use if authenticating as a server.
* Read-only after initable_init(), so it may be read if you either
* hold @init_lock or check for initialization first.
*/
gchar *guid;
/* FLAG_INITIALIZED is set exactly when initable_init() has finished running.
* Inspect @initialization_error to see whether it succeeded or failed.
*
* FLAG_EXIT_ON_CLOSE is the exit-on-close property.
*
* FLAG_CLOSED is the closed property. It may be read at any time, but
* may only be written while holding @lock.
*/
gint atomic_flags; /* (atomic) */
/* If the connection could not be established during initable_init(),
* this GError will be set.
* Read-only after initable_init(), so it may be read if you either
* hold @init_lock or check for initialization first.
*/
GError *initialization_error;
/* The result of g_main_context_ref_thread_default() when the object
* was created (the GObject _init() function) - this is used for delivery
* of the :closed GObject signal.
*
* Only set in the GObject init function, so no locks are needed.
*/
GMainContext *main_context_at_construction;
/* Read-only construct properties, no locks needed */
gchar *address;
GDBusConnectionFlags flags;
/* Map used for managing method replies, protected by @lock */
GHashTable *map_method_serial_to_task; /* guint32 -> owned GTask* */
/* Maps used for managing signal subscription, protected by @lock */
GHashTable *map_rule_to_signal_data; /* match rule (gchar*) -> SignalData */
GHashTable *map_id_to_signal_data; /* id (guint) -> SignalData */
GHashTable *map_sender_unique_name_to_signal_data_array; /* unique sender (gchar*) -> GPtrArray* of SignalData */
/* Maps used for managing exported objects and subtrees,
* protected by @lock
*/
GHashTable *map_object_path_to_eo; /* gchar* -> ExportedObject* */
GHashTable *map_id_to_ei; /* guint -> ExportedInterface* */
GHashTable *map_object_path_to_es; /* gchar* -> ExportedSubtree* */
GHashTable *map_id_to_es; /* guint -> ExportedSubtree* */
/* Map used for storing last used serials for each thread, protected by @lock */
GHashTable *map_thread_to_last_serial;
/* Structure used for message filters, protected by @lock */
GPtrArray *filters;
/* Capabilities negotiated during authentication
* Read-only after initable_init(), so it may be read without holding a
* lock, if you check for initialization first.
*/
GDBusCapabilityFlags capabilities;
/* Protected by @init_lock */
GDBusAuthObserver *authentication_observer;
/* Read-only after initable_init(), so it may be read if you either
* hold @init_lock or check for initialization first.
*/
GCredentials *credentials;
/* set to TRUE when finalizing */
gboolean finalizing;
};
typedef struct ExportedObject ExportedObject;
static void exported_object_free (ExportedObject *eo);
typedef struct ExportedSubtree ExportedSubtree;
static ExportedSubtree *exported_subtree_ref (ExportedSubtree *es);
static void exported_subtree_unref (ExportedSubtree *es);
enum
{
CLOSED_SIGNAL,
LAST_SIGNAL,
};
enum
{
PROP_0,
PROP_STREAM,
PROP_ADDRESS,
PROP_FLAGS,
PROP_GUID,
PROP_UNIQUE_NAME,
PROP_CLOSED,
PROP_EXIT_ON_CLOSE,
PROP_CAPABILITY_FLAGS,
PROP_AUTHENTICATION_OBSERVER,
};
static void distribute_signals (GDBusConnection *connection,
GDBusMessage *message);
static void distribute_method_call (GDBusConnection *connection,
GDBusMessage *message);
static gboolean handle_generic_unlocked (GDBusConnection *connection,
GDBusMessage *message);
static void purge_all_signal_subscriptions (GDBusConnection *connection);
static void purge_all_filters (GDBusConnection *connection);
static void schedule_method_call (GDBusConnection *connection,
GDBusMessage *message,
guint registration_id,
guint subtree_registration_id,
const GDBusInterfaceInfo *interface_info,
const GDBusMethodInfo *method_info,
const GDBusPropertyInfo *property_info,
GVariant *parameters,
const GDBusInterfaceVTable *vtable,
GMainContext *main_context,
gpointer user_data);
#define _G_ENSURE_LOCK(name) do { \
if (G_UNLIKELY (G_TRYLOCK(name))) \
{ \
g_assertion_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
"_G_ENSURE_LOCK: Lock '" #name "' is not locked"); \
} \
} while (FALSE) \
static guint signals[LAST_SIGNAL] = { 0 };
static void initable_iface_init (GInitableIface *initable_iface);
static void async_initable_iface_init (GAsyncInitableIface *async_initable_iface);
G_DEFINE_TYPE_WITH_CODE (GDBusConnection, g_dbus_connection, G_TYPE_OBJECT,
G_IMPLEMENT_INTERFACE (G_TYPE_INITABLE, initable_iface_init)
G_IMPLEMENT_INTERFACE (G_TYPE_ASYNC_INITABLE, async_initable_iface_init)
);
/*
* Check that all members of @connection that can only be accessed after
* the connection is initialized can safely be accessed. If not,
* log a critical warning. This function is a memory barrier.
*
* Returns: %TRUE if initialized
*/
static gboolean
check_initialized (GDBusConnection *connection)
{
/* The access to @atomic_flags isn't conditional, so that this function
* provides a memory barrier for thread-safety even if checks are disabled.
* (If you don't want this stricter guarantee, you can call
* g_return_if_fail (check_initialized (c)).)
*
* This isn't strictly necessary now that we've decided use of an
* uninitialized GDBusConnection is undefined behaviour, but it seems
* better to be as deterministic as is feasible.
*
* (Anything that could suffer a crash from seeing undefined values
* must have a race condition - thread A initializes the connection while
* thread B calls a method without initialization, hoping that thread A will
* win the race - so its behaviour is undefined anyway.)
*/
gint flags = g_atomic_int_get (&connection->atomic_flags);
g_return_val_if_fail (flags & FLAG_INITIALIZED, FALSE);
/* We can safely access this, due to the memory barrier above */
g_return_val_if_fail (connection->initialization_error == NULL, FALSE);
return TRUE;
}
typedef enum {
MAY_BE_UNINITIALIZED = (1<<1)
} CheckUnclosedFlags;
/*
* Check the same thing as check_initialized(), and also that the
* connection is not closed. If the connection is uninitialized,
* raise a critical warning (it's programmer error); if it's closed,
* raise a recoverable GError (it's a runtime error).
*
* This function is a memory barrier.
*
* Returns: %TRUE if initialized and not closed
*/
static gboolean
check_unclosed (GDBusConnection *connection,
CheckUnclosedFlags check,
GError **error)
{
/* check_initialized() is effectively inlined, so we don't waste time
* doing two memory barriers
*/
gint flags = g_atomic_int_get (&connection->atomic_flags);
if (!(check & MAY_BE_UNINITIALIZED))
{
g_return_val_if_fail (flags & FLAG_INITIALIZED, FALSE);
g_return_val_if_fail (connection->initialization_error == NULL, FALSE);
}
if (flags & FLAG_CLOSED)
{
g_set_error_literal (error,
G_IO_ERROR,
G_IO_ERROR_CLOSED,
_("The connection is closed"));
return FALSE;
}
return TRUE;
}
static GHashTable *alive_connections = NULL;
static void
g_dbus_connection_dispose (GObject *object)
{
GDBusConnection *connection = G_DBUS_CONNECTION (object);
G_LOCK (message_bus_lock);
CONNECTION_LOCK (connection);
if (connection->worker != NULL)
{
_g_dbus_worker_stop (connection->worker);
connection->worker = NULL;
if (alive_connections != NULL)
g_warn_if_fail (g_hash_table_remove (alive_connections, connection));
}
else
{
if (alive_connections != NULL)
g_warn_if_fail (!g_hash_table_contains (alive_connections, connection));
}
CONNECTION_UNLOCK (connection);
G_UNLOCK (message_bus_lock);
if (G_OBJECT_CLASS (g_dbus_connection_parent_class)->dispose != NULL)
G_OBJECT_CLASS (g_dbus_connection_parent_class)->dispose (object);
}
static void
g_dbus_connection_finalize (GObject *object)
{
GDBusConnection *connection = G_DBUS_CONNECTION (object);
connection->finalizing = TRUE;
purge_all_signal_subscriptions (connection);
purge_all_filters (connection);
g_ptr_array_unref (connection->filters);
if (connection->authentication_observer != NULL)
g_object_unref (connection->authentication_observer);
if (connection->auth != NULL)
g_object_unref (connection->auth);
if (connection->credentials)
g_object_unref (connection->credentials);
if (connection->stream != NULL)
{
g_object_unref (connection->stream);
connection->stream = NULL;
}
g_free (connection->address);
g_free (connection->guid);
g_free (connection->bus_unique_name);
if (connection->initialization_error != NULL)
g_error_free (connection->initialization_error);
g_hash_table_unref (connection->map_method_serial_to_task);
g_hash_table_unref (connection->map_rule_to_signal_data);
g_hash_table_unref (connection->map_id_to_signal_data);
g_hash_table_unref (connection->map_sender_unique_name_to_signal_data_array);
g_hash_table_unref (connection->map_id_to_ei);
g_hash_table_unref (connection->map_object_path_to_eo);
g_hash_table_unref (connection->map_id_to_es);
g_hash_table_unref (connection->map_object_path_to_es);
g_hash_table_unref (connection->map_thread_to_last_serial);
g_main_context_unref (connection->main_context_at_construction);
g_free (connection->machine_id);
g_mutex_clear (&connection->init_lock);
g_mutex_clear (&connection->lock);
G_OBJECT_CLASS (g_dbus_connection_parent_class)->finalize (object);
}
/* called in any user thread, with the connection's lock not held */
static void
g_dbus_connection_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
GDBusConnection *connection = G_DBUS_CONNECTION (object);
switch (prop_id)
{
case PROP_STREAM:
g_value_set_object (value, g_dbus_connection_get_stream (connection));
break;
case PROP_GUID:
g_value_set_string (value, g_dbus_connection_get_guid (connection));
break;
case PROP_UNIQUE_NAME:
g_value_set_string (value, g_dbus_connection_get_unique_name (connection));
break;
case PROP_CLOSED:
g_value_set_boolean (value, g_dbus_connection_is_closed (connection));
break;
case PROP_EXIT_ON_CLOSE:
g_value_set_boolean (value, g_dbus_connection_get_exit_on_close (connection));
break;
case PROP_CAPABILITY_FLAGS:
g_value_set_flags (value, g_dbus_connection_get_capabilities (connection));
break;
case PROP_FLAGS:
g_value_set_flags (value, g_dbus_connection_get_flags (connection));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* called in any user thread, with the connection's lock not held */
static void
g_dbus_connection_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
GDBusConnection *connection = G_DBUS_CONNECTION (object);
switch (prop_id)
{
case PROP_STREAM:
connection->stream = g_value_dup_object (value);
break;
case PROP_GUID:
connection->guid = g_value_dup_string (value);
break;
case PROP_ADDRESS:
connection->address = g_value_dup_string (value);
break;
case PROP_FLAGS:
connection->flags = g_value_get_flags (value);
break;
case PROP_EXIT_ON_CLOSE:
g_dbus_connection_set_exit_on_close (connection, g_value_get_boolean (value));
break;
case PROP_AUTHENTICATION_OBSERVER:
connection->authentication_observer = g_value_dup_object (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* Base-class implementation of GDBusConnection::closed.
*
* Called in a user thread, by the main context that was thread-default when
* the object was constructed.
*/
static void
g_dbus_connection_real_closed (GDBusConnection *connection,
gboolean remote_peer_vanished,
GError *error)
{
gint flags = g_atomic_int_get (&connection->atomic_flags);
/* Because atomic int access is a memory barrier, we can safely read
* initialization_error without a lock, as long as we do it afterwards.
*/
if (remote_peer_vanished &&
(flags & FLAG_EXIT_ON_CLOSE) != 0 &&
(flags & FLAG_INITIALIZED) != 0 &&
connection->initialization_error == NULL)
{
raise (SIGTERM);
}
}
static void
g_dbus_connection_class_init (GDBusConnectionClass *klass)
{
GObjectClass *gobject_class;
gobject_class = G_OBJECT_CLASS (klass);
gobject_class->finalize = g_dbus_connection_finalize;
gobject_class->dispose = g_dbus_connection_dispose;
gobject_class->set_property = g_dbus_connection_set_property;
gobject_class->get_property = g_dbus_connection_get_property;
klass->closed = g_dbus_connection_real_closed;
/**
* GDBusConnection:stream:
*
* The underlying #GIOStream used for I/O.
*
* If this is passed on construction and is a #GSocketConnection,
* then the corresponding #GSocket will be put into non-blocking mode.
*
* While the #GDBusConnection is active, it will interact with this
* stream from a worker thread, so it is not safe to interact with
* the stream directly.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_STREAM,
g_param_spec_object ("stream", NULL, NULL,
G_TYPE_IO_STREAM,
G_PARAM_READABLE |
G_PARAM_WRITABLE |
G_PARAM_CONSTRUCT_ONLY |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection:address:
*
* A D-Bus address specifying potential endpoints that can be used
* when establishing the connection.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_ADDRESS,
g_param_spec_string ("address", NULL, NULL,
NULL,
G_PARAM_WRITABLE |
G_PARAM_CONSTRUCT_ONLY |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection:flags:
*
* Flags from the #GDBusConnectionFlags enumeration.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_FLAGS,
g_param_spec_flags ("flags", NULL, NULL,
G_TYPE_DBUS_CONNECTION_FLAGS,
G_DBUS_CONNECTION_FLAGS_NONE,
G_PARAM_READABLE |
G_PARAM_WRITABLE |
G_PARAM_CONSTRUCT_ONLY |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection:guid:
*
* The GUID of the peer performing the role of server when
* authenticating.
*
* If you are constructing a #GDBusConnection and pass
* %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER in the
* #GDBusConnection:flags property then you **must** also set this
* property to a valid guid.
*
* If you are constructing a #GDBusConnection and pass
* %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT in the
* #GDBusConnection:flags property you will be able to read the GUID
* of the other peer here after the connection has been successfully
* initialized.
*
* Note that the
* [D-Bus specification](https://dbus.freedesktop.org/doc/dbus-specification.html#addresses)
* uses the term ‘UUID’ to refer to this, whereas GLib consistently uses the
* term ‘GUID’ for historical reasons.
*
* Despite its name, the format of #GDBusConnection:guid does not follow
* [RFC 4122](https://datatracker.ietf.org/doc/html/rfc4122) or the Microsoft
* GUID format.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_GUID,
g_param_spec_string ("guid", NULL, NULL,
NULL,
G_PARAM_READABLE |
G_PARAM_WRITABLE |
G_PARAM_CONSTRUCT_ONLY |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection:unique-name:
*
* The unique name as assigned by the message bus or %NULL if the
* connection is not open or not a message bus connection.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_UNIQUE_NAME,
g_param_spec_string ("unique-name", NULL, NULL,
NULL,
G_PARAM_READABLE |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection:closed:
*
* A boolean specifying whether the connection has been closed.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_CLOSED,
g_param_spec_boolean ("closed", NULL, NULL,
FALSE,
G_PARAM_READABLE |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection:exit-on-close:
*
* A boolean specifying whether the process will be terminated (by
* calling `raise(SIGTERM)`) if the connection is closed by the
* remote peer.
*
* Note that #GDBusConnection objects returned by g_bus_get_finish()
* and g_bus_get_sync() will (usually) have this property set to %TRUE.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_EXIT_ON_CLOSE,
g_param_spec_boolean ("exit-on-close", NULL, NULL,
FALSE,
G_PARAM_READABLE |
G_PARAM_WRITABLE |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection:capabilities:
*
* Flags from the #GDBusCapabilityFlags enumeration
* representing connection features negotiated with the other peer.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_CAPABILITY_FLAGS,
g_param_spec_flags ("capabilities", NULL, NULL,
G_TYPE_DBUS_CAPABILITY_FLAGS,
G_DBUS_CAPABILITY_FLAGS_NONE,
G_PARAM_READABLE |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection:authentication-observer:
*
* A #GDBusAuthObserver object to assist in the authentication process or %NULL.
*
* Since: 2.26
*/
g_object_class_install_property (gobject_class,
PROP_AUTHENTICATION_OBSERVER,
g_param_spec_object ("authentication-observer", NULL, NULL,
G_TYPE_DBUS_AUTH_OBSERVER,
G_PARAM_WRITABLE |
G_PARAM_CONSTRUCT_ONLY |
G_PARAM_STATIC_NAME |
G_PARAM_STATIC_BLURB |
G_PARAM_STATIC_NICK));
/**
* GDBusConnection::closed:
* @connection: the #GDBusConnection emitting the signal
* @remote_peer_vanished: %TRUE if @connection is closed because the
* remote peer closed its end of the connection
* @error: (nullable): a #GError with more details about the event or %NULL
*
* Emitted when the connection is closed.
*
* The cause of this event can be
*
* - If g_dbus_connection_close() is called. In this case
* @remote_peer_vanished is set to %FALSE and @error is %NULL.
*
* - If the remote peer closes the connection. In this case
* @remote_peer_vanished is set to %TRUE and @error is set.
*
* - If the remote peer sends invalid or malformed data. In this
* case @remote_peer_vanished is set to %FALSE and @error is set.
*
* Upon receiving this signal, you should give up your reference to
* @connection. You are guaranteed that this signal is emitted only
* once.
*
* Since: 2.26
*/
signals[CLOSED_SIGNAL] = g_signal_new (I_("closed"),
G_TYPE_DBUS_CONNECTION,
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GDBusConnectionClass, closed),
NULL,
NULL,
_g_cclosure_marshal_VOID__BOOLEAN_BOXED,
G_TYPE_NONE,
2,
G_TYPE_BOOLEAN,
G_TYPE_ERROR);
g_signal_set_va_marshaller (signals[CLOSED_SIGNAL],
G_TYPE_FROM_CLASS (klass),
_g_cclosure_marshal_VOID__BOOLEAN_BOXEDv);
}
static void
g_dbus_connection_init (GDBusConnection *connection)
{
g_mutex_init (&connection->lock);
g_mutex_init (&connection->init_lock);
connection->map_method_serial_to_task = g_hash_table_new_full (g_direct_hash, g_direct_equal, NULL, g_object_unref);
connection->map_rule_to_signal_data = g_hash_table_new (g_str_hash,
g_str_equal);
connection->map_id_to_signal_data = g_hash_table_new (g_direct_hash,
g_direct_equal);
connection->map_sender_unique_name_to_signal_data_array = g_hash_table_new_full (g_str_hash,
g_str_equal,
g_free,
(GDestroyNotify) g_ptr_array_unref);
connection->map_object_path_to_eo = g_hash_table_new_full (g_str_hash,
g_str_equal,
NULL,
(GDestroyNotify) exported_object_free);
connection->map_id_to_ei = g_hash_table_new (g_direct_hash,
g_direct_equal);
connection->map_object_path_to_es = g_hash_table_new_full (g_str_hash,
g_str_equal,
NULL,
(GDestroyNotify) exported_subtree_unref);
connection->map_id_to_es = g_hash_table_new (g_direct_hash,
g_direct_equal);
connection->map_thread_to_last_serial = g_hash_table_new (g_direct_hash,
g_direct_equal);
connection->main_context_at_construction = g_main_context_ref_thread_default ();
connection->filters = g_ptr_array_new ();
}
/**
* g_dbus_connection_get_stream:
* @connection: a #GDBusConnection
*
* Gets the underlying stream used for IO.
*
* While the #GDBusConnection is active, it will interact with this
* stream from a worker thread, so it is not safe to interact with
* the stream directly.
*
* Returns: (transfer none) (not nullable): the stream used for IO
*
* Since: 2.26
*/
GIOStream *
g_dbus_connection_get_stream (GDBusConnection *connection)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), NULL);
/* do not use g_return_val_if_fail(), we want the memory barrier */
if (!check_initialized (connection))
return NULL;
return connection->stream;
}
/**
* g_dbus_connection_start_message_processing:
* @connection: a #GDBusConnection
*
* If @connection was created with
* %G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING, this method
* starts processing messages. Does nothing on if @connection wasn't
* created with this flag or if the method has already been called.
*
* Since: 2.26
*/
void
g_dbus_connection_start_message_processing (GDBusConnection *connection)
{
g_return_if_fail (G_IS_DBUS_CONNECTION (connection));
/* do not use g_return_val_if_fail(), we want the memory barrier */
if (!check_initialized (connection))
return;
g_assert (connection->worker != NULL);
_g_dbus_worker_unfreeze (connection->worker);
}
/**
* g_dbus_connection_is_closed:
* @connection: a #GDBusConnection
*
* Gets whether @connection is closed.
*
* Returns: %TRUE if the connection is closed, %FALSE otherwise
*
* Since: 2.26
*/
gboolean
g_dbus_connection_is_closed (GDBusConnection *connection)
{
gint flags;
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), FALSE);
flags = g_atomic_int_get (&connection->atomic_flags);
return (flags & FLAG_CLOSED) ? TRUE : FALSE;
}
/**
* g_dbus_connection_get_capabilities:
* @connection: a #GDBusConnection
*
* Gets the capabilities negotiated with the remote peer
*
* Returns: zero or more flags from the #GDBusCapabilityFlags enumeration
*
* Since: 2.26
*/
GDBusCapabilityFlags
g_dbus_connection_get_capabilities (GDBusConnection *connection)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), G_DBUS_CAPABILITY_FLAGS_NONE);
/* do not use g_return_val_if_fail(), we want the memory barrier */
if (!check_initialized (connection))
return G_DBUS_CAPABILITY_FLAGS_NONE;
return connection->capabilities;
}
/**
* g_dbus_connection_get_flags:
* @connection: a #GDBusConnection
*
* Gets the flags used to construct this connection
*
* Returns: zero or more flags from the #GDBusConnectionFlags enumeration
*
* Since: 2.60
*/
GDBusConnectionFlags
g_dbus_connection_get_flags (GDBusConnection *connection)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), G_DBUS_CONNECTION_FLAGS_NONE);
/* do not use g_return_val_if_fail(), we want the memory barrier */
if (!check_initialized (connection))
return G_DBUS_CONNECTION_FLAGS_NONE;
return connection->flags;
}
/* ---------------------------------------------------------------------------------------------------- */
/* Called in a temporary thread without holding locks. */
static void
flush_in_thread_func (GTask *task,
gpointer source_object,
gpointer task_data,
GCancellable *cancellable)
{
GError *error = NULL;
if (g_dbus_connection_flush_sync (source_object,
cancellable,
&error))
g_task_return_boolean (task, TRUE);
else
g_task_return_error (task, error);
}
/**
* g_dbus_connection_flush:
* @connection: a #GDBusConnection
* @cancellable: (nullable): a #GCancellable or %NULL
* @callback: (nullable): a #GAsyncReadyCallback to call when the
* request is satisfied or %NULL if you don't care about the result
* @user_data: The data to pass to @callback
*
* Asynchronously flushes @connection, that is, writes all queued
* outgoing message to the transport and then flushes the transport
* (using g_output_stream_flush_async()). This is useful in programs
* that wants to emit a D-Bus signal and then exit immediately. Without
* flushing the connection, there is no guaranteed that the message has
* been sent to the networking buffers in the OS kernel.
*
* This is an asynchronous method. When the operation is finished,
* @callback will be invoked in the
* [thread-default main context][g-main-context-push-thread-default]
* of the thread you are calling this method from. You can
* then call g_dbus_connection_flush_finish() to get the result of the
* operation. See g_dbus_connection_flush_sync() for the synchronous
* version.
*
* Since: 2.26
*/
void
g_dbus_connection_flush (GDBusConnection *connection,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GTask *task;
g_return_if_fail (G_IS_DBUS_CONNECTION (connection));
task = g_task_new (connection, cancellable, callback, user_data);
g_task_set_source_tag (task, g_dbus_connection_flush);
g_task_run_in_thread (task, flush_in_thread_func);
g_object_unref (task);
}
/**
* g_dbus_connection_flush_finish:
* @connection: a #GDBusConnection
* @res: a #GAsyncResult obtained from the #GAsyncReadyCallback passed
* to g_dbus_connection_flush()
* @error: return location for error or %NULL
*
* Finishes an operation started with g_dbus_connection_flush().
*
* Returns: %TRUE if the operation succeeded, %FALSE if @error is set
*
* Since: 2.26
*/
gboolean
g_dbus_connection_flush_finish (GDBusConnection *connection,
GAsyncResult *res,
GError **error)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), FALSE);
g_return_val_if_fail (g_task_is_valid (res, connection), FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
return g_task_propagate_boolean (G_TASK (res), error);
}
/**
* g_dbus_connection_flush_sync:
* @connection: a #GDBusConnection
* @cancellable: (nullable): a #GCancellable or %NULL
* @error: return location for error or %NULL
*
* Synchronously flushes @connection. The calling thread is blocked
* until this is done. See g_dbus_connection_flush() for the
* asynchronous version of this method and more details about what it
* does.
*
* Returns: %TRUE if the operation succeeded, %FALSE if @error is set
*
* Since: 2.26
*/
gboolean
g_dbus_connection_flush_sync (GDBusConnection *connection,
GCancellable *cancellable,
GError **error)
{
gboolean ret;
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
ret = FALSE;
/* This is only a best-effort attempt to see whether the connection is
* closed, so it doesn't need the lock. If the connection closes just
* after this check, but before scheduling the flush operation, the
* result will be more or less the same as if the connection closed while
* the flush operation was pending - it'll fail with either CLOSED or
* CANCELLED.
*/
if (!check_unclosed (connection, 0, error))
goto out;
g_assert (connection->worker != NULL);
ret = _g_dbus_worker_flush_sync (connection->worker,
cancellable,
error);
out:
return ret;
}
/* ---------------------------------------------------------------------------------------------------- */
typedef struct
{
GDBusConnection *connection;
GError *error;
gboolean remote_peer_vanished;
} EmitClosedData;
static void
emit_closed_data_free (EmitClosedData *data)
{
g_object_unref (data->connection);
if (data->error != NULL)
g_error_free (data->error);
g_free (data);
}
/* Called in a user thread that has acquired the main context that was
* thread-default when the object was constructed
*/
static gboolean
emit_closed_in_idle (gpointer user_data)
{
EmitClosedData *data = user_data;
gboolean result;
g_object_notify (G_OBJECT (data->connection), "closed");
g_signal_emit (data->connection,
signals[CLOSED_SIGNAL],
0,
data->remote_peer_vanished,
data->error,
&result);
return FALSE;
}
/* Can be called from any thread, must hold lock.
* FLAG_CLOSED must already have been set.
*/
static void
schedule_closed_unlocked (GDBusConnection *connection,
gboolean remote_peer_vanished,
GError *error)
{
GSource *idle_source;
EmitClosedData *data;
CONNECTION_ENSURE_LOCK (connection);
data = g_new0 (EmitClosedData, 1);
data->connection = g_object_ref (connection);
data->remote_peer_vanished = remote_peer_vanished;
data->error = error != NULL ? g_error_copy (error) : NULL;
idle_source = g_idle_source_new ();
g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
g_source_set_callback (idle_source,
emit_closed_in_idle,
data,
(GDestroyNotify) emit_closed_data_free);
g_source_set_static_name (idle_source, "[gio] emit_closed_in_idle");
g_source_attach (idle_source, connection->main_context_at_construction);
g_source_unref (idle_source);
}
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_dbus_connection_close:
* @connection: a #GDBusConnection
* @cancellable: (nullable): a #GCancellable or %NULL
* @callback: (nullable): a #GAsyncReadyCallback to call when the request is
* satisfied or %NULL if you don't care about the result
* @user_data: The data to pass to @callback
*
* Closes @connection. Note that this never causes the process to
* exit (this might only happen if the other end of a shared message
* bus connection disconnects, see #GDBusConnection:exit-on-close).
*
* Once the connection is closed, operations such as sending a message
* will return with the error %G_IO_ERROR_CLOSED. Closing a connection
* will not automatically flush the connection so queued messages may
* be lost. Use g_dbus_connection_flush() if you need such guarantees.
*
* If @connection is already closed, this method fails with
* %G_IO_ERROR_CLOSED.
*
* When @connection has been closed, the #GDBusConnection::closed
* signal is emitted in the
* [thread-default main context][g-main-context-push-thread-default]
* of the thread that @connection was constructed in.
*
* This is an asynchronous method. When the operation is finished,
* @callback will be invoked in the
* [thread-default main context][g-main-context-push-thread-default]
* of the thread you are calling this method from. You can
* then call g_dbus_connection_close_finish() to get the result of the
* operation. See g_dbus_connection_close_sync() for the synchronous
* version.
*
* Since: 2.26
*/
void
g_dbus_connection_close (GDBusConnection *connection,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GTask *task;
g_return_if_fail (G_IS_DBUS_CONNECTION (connection));
/* do not use g_return_val_if_fail(), we want the memory barrier */
if (!check_initialized (connection))
return;
g_assert (connection->worker != NULL);
task = g_task_new (connection, cancellable, callback, user_data);
g_task_set_source_tag (task, g_dbus_connection_close);
_g_dbus_worker_close (connection->worker, task);
g_object_unref (task);
}
/**
* g_dbus_connection_close_finish:
* @connection: a #GDBusConnection
* @res: a #GAsyncResult obtained from the #GAsyncReadyCallback passed
* to g_dbus_connection_close()
* @error: return location for error or %NULL
*
* Finishes an operation started with g_dbus_connection_close().
*
* Returns: %TRUE if the operation succeeded, %FALSE if @error is set
*
* Since: 2.26
*/
gboolean
g_dbus_connection_close_finish (GDBusConnection *connection,
GAsyncResult *res,
GError **error)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), FALSE);
g_return_val_if_fail (g_task_is_valid (res, connection), FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
return g_task_propagate_boolean (G_TASK (res), error);
}
typedef struct {
GMainLoop *loop;
GAsyncResult *result;
} SyncCloseData;
/* Can be called by any thread, without the connection lock */
static void
sync_close_cb (GObject *source_object,
GAsyncResult *res,
gpointer user_data)
{
SyncCloseData *data = user_data;
data->result = g_object_ref (res);
g_main_loop_quit (data->loop);
}
/**
* g_dbus_connection_close_sync:
* @connection: a #GDBusConnection
* @cancellable: (nullable): a #GCancellable or %NULL
* @error: return location for error or %NULL
*
* Synchronously closes @connection. The calling thread is blocked
* until this is done. See g_dbus_connection_close() for the
* asynchronous version of this method and more details about what it
* does.
*
* Returns: %TRUE if the operation succeeded, %FALSE if @error is set
*
* Since: 2.26
*/
gboolean
g_dbus_connection_close_sync (GDBusConnection *connection,
GCancellable *cancellable,
GError **error)
{
gboolean ret;
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
ret = FALSE;
if (check_unclosed (connection, 0, error))
{
GMainContext *context;
SyncCloseData data;
context = g_main_context_new ();
g_main_context_push_thread_default (context);
data.loop = g_main_loop_new (context, TRUE);
data.result = NULL;
g_dbus_connection_close (connection, cancellable, sync_close_cb, &data);
g_main_loop_run (data.loop);
ret = g_dbus_connection_close_finish (connection, data.result, error);
g_object_unref (data.result);
g_main_loop_unref (data.loop);
g_main_context_pop_thread_default (context);
g_main_context_unref (context);
}
return ret;
}
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_dbus_connection_get_last_serial:
* @connection: a #GDBusConnection
*
* Retrieves the last serial number assigned to a #GDBusMessage on
* the current thread. This includes messages sent via both low-level
* API such as g_dbus_connection_send_message() as well as
* high-level API such as g_dbus_connection_emit_signal(),
* g_dbus_connection_call() or g_dbus_proxy_call().
*
* Returns: the last used serial or zero when no message has been sent
* within the current thread
*
* Since: 2.34
*/
guint32
g_dbus_connection_get_last_serial (GDBusConnection *connection)
{
guint32 ret;
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), 0);
CONNECTION_LOCK (connection);
ret = GPOINTER_TO_UINT (g_hash_table_lookup (connection->map_thread_to_last_serial,
g_thread_self ()));
CONNECTION_UNLOCK (connection);
return ret;
}
/* ---------------------------------------------------------------------------------------------------- */
/* Can be called by any thread, with the connection lock held */
static gboolean
g_dbus_connection_send_message_unlocked (GDBusConnection *connection,
GDBusMessage *message,
GDBusSendMessageFlags flags,
guint32 *out_serial,
GError **error)
{
guchar *blob;
gsize blob_size;
guint32 serial_to_use;
CONNECTION_ENSURE_LOCK (connection);
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), FALSE);
g_return_val_if_fail (G_IS_DBUS_MESSAGE (message), FALSE);
/* TODO: check all necessary headers are present */
if (out_serial != NULL)
*out_serial = 0;
/* If we're in initable_init(), don't check for being initialized, to avoid
* chicken-and-egg problems. initable_init() is responsible for setting up
* our prerequisites (mainly connection->worker), and only calling us
* from its own thread (so no memory barrier is needed).
*/
if (!check_unclosed (connection,
(flags & SEND_MESSAGE_FLAGS_INITIALIZING) ? MAY_BE_UNINITIALIZED : 0,
error))
return FALSE;
blob = g_dbus_message_to_blob (message,
&blob_size,
connection->capabilities,
error);
if (blob == NULL)
return FALSE;
if (flags & G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL)
serial_to_use = g_dbus_message_get_serial (message);
else
serial_to_use = ++connection->last_serial; /* TODO: handle overflow */
switch (blob[0])
{
case 'l':
((guint32 *) blob)[2] = GUINT32_TO_LE (serial_to_use);
break;
case 'B':
((guint32 *) blob)[2] = GUINT32_TO_BE (serial_to_use);
break;
default:
g_assert_not_reached ();
break;
}
#if 0
g_printerr ("Writing message of %" G_GSIZE_FORMAT " bytes (serial %d) on %p:\n",
blob_size, serial_to_use, connection);
g_printerr ("----\n");
hexdump (blob, blob_size);
g_printerr ("----\n");
#endif
/* TODO: use connection->auth to encode the blob */
if (out_serial != NULL)
*out_serial = serial_to_use;
/* store used serial for the current thread */
/* TODO: watch the thread disposal and remove associated record
* from hashtable
* - see https://bugzilla.gnome.org/show_bug.cgi?id=676825#c7
*/
g_hash_table_replace (connection->map_thread_to_last_serial,
g_thread_self (),
GUINT_TO_POINTER (serial_to_use));
if (!(flags & G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL))
g_dbus_message_set_serial (message, serial_to_use);
g_dbus_message_lock (message);
_g_dbus_worker_send_message (connection->worker,
message,
(gchar*) blob, /* transfer ownership */
blob_size);
return TRUE;
}
/**
* g_dbus_connection_send_message:
* @connection: a #GDBusConnection
* @message: a #GDBusMessage
* @flags: flags affecting how the message is sent
* @out_serial: (out) (optional): return location for serial number assigned
* to @message when sending it or %NULL
* @error: Return location for error or %NULL
*
* Asynchronously sends @message to the peer represented by @connection.
*
* Unless @flags contain the
* %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag, the serial number
* will be assigned by @connection and set on @message via
* g_dbus_message_set_serial(). If @out_serial is not %NULL, then the
* serial number used will be written to this location prior to
* submitting the message to the underlying transport. While it has a `volatile`
* qualifier, this is a historical artifact and the argument passed to it should
* not be `volatile`.
*
* If @connection is closed then the operation will fail with
* %G_IO_ERROR_CLOSED. If @message is not well-formed,
* the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.
*
* See this [server][gdbus-server] and [client][gdbus-unix-fd-client]
* for an example of how to use this low-level API to send and receive
* UNIX file descriptors.
*
* Note that @message must be unlocked, unless @flags contain the
* %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag.
*
* Returns: %TRUE if the message was well-formed and queued for
* transmission, %FALSE if @error is set
*
* Since: 2.26
*/
gboolean
g_dbus_connection_send_message (GDBusConnection *connection,
GDBusMessage *message,
GDBusSendMessageFlags flags,
volatile guint32 *out_serial,
GError **error)
{
gboolean ret;
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), FALSE);
g_return_val_if_fail (G_IS_DBUS_MESSAGE (message), FALSE);
g_return_val_if_fail ((flags & G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL) || !g_dbus_message_get_locked (message), FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
CONNECTION_LOCK (connection);
ret = g_dbus_connection_send_message_unlocked (connection, message, flags, (guint32 *) out_serial, error);
CONNECTION_UNLOCK (connection);
return ret;
}
/* ---------------------------------------------------------------------------------------------------- */
typedef struct
{
guint32 serial;
gulong cancellable_handler_id;
GSource *cancelled_idle_source; /* (owned) (nullable) */
GSource *timeout_source; /* (owned) (nullable) */
gboolean delivered;
} SendMessageData;
/* Can be called from any thread with or without lock held */
static void
send_message_data_free (SendMessageData *data)
{
/* These should already have been cleared by send_message_with_reply_cleanup(). */
g_assert (data->timeout_source == NULL);
g_assert (data->cancellable_handler_id == 0);
g_slice_free (SendMessageData, data);
}
/* ---------------------------------------------------------------------------------------------------- */
/* can be called from any thread with lock held; @task is (transfer none) */
static void
send_message_with_reply_cleanup (GTask *task, gboolean remove)
{
GDBusConnection *connection = g_task_get_source_object (task);
SendMessageData *data = g_task_get_task_data (task);
CONNECTION_ENSURE_LOCK (connection);
g_assert (!data->delivered);
data->delivered = TRUE;
if (data->timeout_source != NULL)
{
g_source_destroy (data->timeout_source);
g_clear_pointer (&data->timeout_source, g_source_unref);
}
if (data->cancellable_handler_id > 0)
{
g_cancellable_disconnect (g_task_get_cancellable (task), data->cancellable_handler_id);
data->cancellable_handler_id = 0;
}
if (data->cancelled_idle_source != NULL)
{
g_source_destroy (data->cancelled_idle_source);
g_clear_pointer (&data->cancelled_idle_source, g_source_unref);
}
if (remove)
{
gboolean removed = g_hash_table_remove (connection->map_method_serial_to_task,
GUINT_TO_POINTER (data->serial));
g_warn_if_fail (removed);
}
}
/* ---------------------------------------------------------------------------------------------------- */
/* Called from GDBus worker thread with lock held; @task is (transfer none). */
static void
send_message_data_deliver_reply_unlocked (GTask *task,
GDBusMessage *reply)
{
SendMessageData *data = g_task_get_task_data (task);
if (data->delivered)
goto out;
g_task_return_pointer (task, g_object_ref (reply), g_object_unref);
send_message_with_reply_cleanup (task, TRUE);
out:
;
}
/* Called from a user thread, lock is not held; @task is (transfer none) */
static void
send_message_data_deliver_error (GTask *task,
GQuark domain,
gint code,
const char *message)
{
GDBusConnection *connection = g_task_get_source_object (task);
SendMessageData *data = g_task_get_task_data (task);
CONNECTION_LOCK (connection);
if (data->delivered)
{
CONNECTION_UNLOCK (connection);
return;
}
/* Hold a ref on @task as send_message_with_reply_cleanup() will remove it
* from the task map and could end up dropping the last reference */
g_object_ref (task);
send_message_with_reply_cleanup (task, TRUE);
CONNECTION_UNLOCK (connection);
g_task_return_new_error_literal (task, domain, code, message);
g_object_unref (task);
}
/* ---------------------------------------------------------------------------------------------------- */
/* Called from a user thread, lock is not held; @task is (transfer none) */
static gboolean
send_message_with_reply_cancelled_idle_cb (gpointer user_data)
{
GTask *task = user_data;
send_message_data_deliver_error (task, G_IO_ERROR, G_IO_ERROR_CANCELLED,
_("Operation was cancelled"));
return G_SOURCE_REMOVE;
}
/* Can be called from any thread with or without lock held */
static void
send_message_with_reply_cancelled_cb (GCancellable *cancellable,
gpointer user_data)
{
GTask *task = user_data;
SendMessageData *data = g_task_get_task_data (task);
/* postpone cancellation to idle handler since we may be called directly
* via g_cancellable_connect() (e.g. holding lock)
*/
if (data->cancelled_idle_source != NULL)
return;
data->cancelled_idle_source = g_idle_source_new ();
g_source_set_static_name (data->cancelled_idle_source, "[gio] send_message_with_reply_cancelled_idle_cb");
g_task_attach_source (task, data->cancelled_idle_source, send_message_with_reply_cancelled_idle_cb);
}
/* ---------------------------------------------------------------------------------------------------- */
/* Called from a user thread, lock is not held; @task is (transfer none) */
static gboolean
send_message_with_reply_timeout_cb (gpointer user_data)
{
GTask *task = user_data;
send_message_data_deliver_error (task, G_IO_ERROR, G_IO_ERROR_TIMED_OUT,
_("Timeout was reached"));
return G_SOURCE_REMOVE;
}
/* ---------------------------------------------------------------------------------------------------- */
/* Called from a user thread, connection's lock is held */
static void
g_dbus_connection_send_message_with_reply_unlocked (GDBusConnection *connection,
GDBusMessage *message,
GDBusSendMessageFlags flags,
gint timeout_msec,
guint32 *out_serial,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GTask *task;
SendMessageData *data;
GError *error = NULL;
guint32 serial;
if (out_serial == NULL)
out_serial = &serial;
if (timeout_msec == -1)
timeout_msec = 25 * 1000;
data = g_slice_new0 (SendMessageData);
task = g_task_new (connection, cancellable, callback, user_data);
g_task_set_source_tag (task,
g_dbus_connection_send_message_with_reply_unlocked);
g_task_set_task_data (task, data, (GDestroyNotify) send_message_data_free);
if (g_task_return_error_if_cancelled (task))
{
g_object_unref (task);
return;
}
if (!g_dbus_connection_send_message_unlocked (connection, message, flags, out_serial, &error))
{
g_task_return_error (task, error);
g_object_unref (task);
return;
}
data->serial = *out_serial;
if (cancellable != NULL)
{
data->cancellable_handler_id = g_cancellable_connect (cancellable,
G_CALLBACK (send_message_with_reply_cancelled_cb),
g_object_ref (task),
g_object_unref);
}
if (timeout_msec != G_MAXINT)
{
data->timeout_source = g_timeout_source_new (timeout_msec);
g_source_set_static_name (data->timeout_source, "[gio] send_message_with_reply_unlocked");
g_task_attach_source (task, data->timeout_source,
(GSourceFunc) send_message_with_reply_timeout_cb);
}
g_hash_table_insert (connection->map_method_serial_to_task,
GUINT_TO_POINTER (*out_serial),
g_steal_pointer (&task));
}
/**
* g_dbus_connection_send_message_with_reply:
* @connection: a #GDBusConnection
* @message: a #GDBusMessage
* @flags: flags affecting how the message is sent
* @timeout_msec: the timeout in milliseconds, -1 to use the default
* timeout or %G_MAXINT for no timeout
* @out_serial: (out) (optional): return location for serial number assigned
* to @message when sending it or %NULL
* @cancellable: (nullable): a #GCancellable or %NULL
* @callback: (nullable): a #GAsyncReadyCallback to call when the request
* is satisfied or %NULL if you don't care about the result
* @user_data: The data to pass to @callback
*
* Asynchronously sends @message to the peer represented by @connection.
*
* Unless @flags contain the
* %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag, the serial number
* will be assigned by @connection and set on @message via
* g_dbus_message_set_serial(). If @out_serial is not %NULL, then the
* serial number used will be written to this location prior to
* submitting the message to the underlying transport. While it has a `volatile`
* qualifier, this is a historical artifact and the argument passed to it should
* not be `volatile`.
*
* If @connection is closed then the operation will fail with
* %G_IO_ERROR_CLOSED. If @cancellable is canceled, the operation will
* fail with %G_IO_ERROR_CANCELLED. If @message is not well-formed,
* the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.
*
* This is an asynchronous method. When the operation is finished, @callback
* will be invoked in the
* [thread-default main context][g-main-context-push-thread-default]
* of the thread you are calling this method from. You can then call
* g_dbus_connection_send_message_with_reply_finish() to get the result of the operation.
* See g_dbus_connection_send_message_with_reply_sync() for the synchronous version.
*
* Note that @message must be unlocked, unless @flags contain the
* %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag.
*
* See this [server][gdbus-server] and [client][gdbus-unix-fd-client]
* for an example of how to use this low-level API to send and receive
* UNIX file descriptors.
*
* Since: 2.26
*/
void
g_dbus_connection_send_message_with_reply (GDBusConnection *connection,
GDBusMessage *message,
GDBusSendMessageFlags flags,
gint timeout_msec,
volatile guint32 *out_serial,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
g_return_if_fail (G_IS_DBUS_CONNECTION (connection));
g_return_if_fail (G_IS_DBUS_MESSAGE (message));
g_return_if_fail ((flags & G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL) || !g_dbus_message_get_locked (message));
g_return_if_fail (timeout_msec >= 0 || timeout_msec == -1);
CONNECTION_LOCK (connection);
g_dbus_connection_send_message_with_reply_unlocked (connection,
message,
flags,
timeout_msec,
(guint32 *) out_serial,
cancellable,
callback,
user_data);
CONNECTION_UNLOCK (connection);
}
/**
* g_dbus_connection_send_message_with_reply_finish:
* @connection: a #GDBusConnection
* @res: a #GAsyncResult obtained from the #GAsyncReadyCallback passed to
* g_dbus_connection_send_message_with_reply()
* @error: teturn location for error or %NULL
*
* Finishes an operation started with g_dbus_connection_send_message_with_reply().
*
* Note that @error is only set if a local in-process error
* occurred. That is to say that the returned #GDBusMessage object may
* be of type %G_DBUS_MESSAGE_TYPE_ERROR. Use
* g_dbus_message_to_gerror() to transcode this to a #GError.
*
* See this [server][gdbus-server] and [client][gdbus-unix-fd-client]
* for an example of how to use this low-level API to send and receive
* UNIX file descriptors.
*
* Returns: (transfer full): a locked #GDBusMessage or %NULL if @error is set
*
* Since: 2.26
*/
GDBusMessage *
g_dbus_connection_send_message_with_reply_finish (GDBusConnection *connection,
GAsyncResult *res,
GError **error)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), NULL);
g_return_val_if_fail (g_task_is_valid (res, connection), NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
return g_task_propagate_pointer (G_TASK (res), error);
}
/* ---------------------------------------------------------------------------------------------------- */
typedef struct
{
GAsyncResult *res;
GMainContext *context;
GMainLoop *loop;
} SendMessageSyncData;
/* Called from a user thread, lock is not held */
static void
send_message_with_reply_sync_cb (GDBusConnection *connection,
GAsyncResult *res,
gpointer user_data)
{
SendMessageSyncData *data = user_data;
data->res = g_object_ref (res);
g_main_loop_quit (data->loop);
}
/**
* g_dbus_connection_send_message_with_reply_sync:
* @connection: a #GDBusConnection
* @message: a #GDBusMessage
* @flags: flags affecting how the message is sent.
* @timeout_msec: the timeout in milliseconds, -1 to use the default
* timeout or %G_MAXINT for no timeout
* @out_serial: (out) (optional): return location for serial number
* assigned to @message when sending it or %NULL
* @cancellable: (nullable): a #GCancellable or %NULL
* @error: return location for error or %NULL
*
* Synchronously sends @message to the peer represented by @connection
* and blocks the calling thread until a reply is received or the
* timeout is reached. See g_dbus_connection_send_message_with_reply()
* for the asynchronous version of this method.
*
* Unless @flags contain the
* %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag, the serial number
* will be assigned by @connection and set on @message via
* g_dbus_message_set_serial(). If @out_serial is not %NULL, then the
* serial number used will be written to this location prior to
* submitting the message to the underlying transport. While it has a `volatile`
* qualifier, this is a historical artifact and the argument passed to it should
* not be `volatile`.
*
* If @connection is closed then the operation will fail with
* %G_IO_ERROR_CLOSED. If @cancellable is canceled, the operation will
* fail with %G_IO_ERROR_CANCELLED. If @message is not well-formed,
* the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.
*
* Note that @error is only set if a local in-process error
* occurred. That is to say that the returned #GDBusMessage object may
* be of type %G_DBUS_MESSAGE_TYPE_ERROR. Use
* g_dbus_message_to_gerror() to transcode this to a #GError.
*
* See this [server][gdbus-server] and [client][gdbus-unix-fd-client]
* for an example of how to use this low-level API to send and receive
* UNIX file descriptors.
*
* Note that @message must be unlocked, unless @flags contain the
* %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag.
*
* Returns: (transfer full): a locked #GDBusMessage that is the reply
* to @message or %NULL if @error is set
*
* Since: 2.26
*/
GDBusMessage *
g_dbus_connection_send_message_with_reply_sync (GDBusConnection *connection,
GDBusMessage *message,
GDBusSendMessageFlags flags,
gint timeout_msec,
volatile guint32 *out_serial,
GCancellable *cancellable,
GError **error)
{
SendMessageSyncData data;
GDBusMessage *reply;
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), NULL);
g_return_val_if_fail (G_IS_DBUS_MESSAGE (message), NULL);
g_return_val_if_fail ((flags & G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL) || !g_dbus_message_get_locked (message), NULL);
g_return_val_if_fail (timeout_msec >= 0 || timeout_msec == -1, NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
data.res = NULL;
data.context = g_main_context_new ();
data.loop = g_main_loop_new (data.context, FALSE);
g_main_context_push_thread_default (data.context);
g_dbus_connection_send_message_with_reply (connection,
message,
flags,
timeout_msec,
out_serial,
cancellable,
(GAsyncReadyCallback) send_message_with_reply_sync_cb,
&data);
g_main_loop_run (data.loop);
reply = g_dbus_connection_send_message_with_reply_finish (connection,
data.res,
error);
g_main_context_pop_thread_default (data.context);
g_main_context_unref (data.context);
g_main_loop_unref (data.loop);
if (data.res)
g_object_unref (data.res);
return reply;
}
/* ---------------------------------------------------------------------------------------------------- */
typedef struct
{
guint id;
guint ref_count;
GDBusMessageFilterFunction filter_function;
gpointer user_data;
GDestroyNotify user_data_free_func;
GMainContext *context;
} FilterData;
static void
filter_data_destroy (FilterData *filter, gboolean notify_sync)
{
if (notify_sync)
{
if (filter->user_data_free_func != NULL)
filter->user_data_free_func (filter->user_data);
}
else
{
call_destroy_notify (filter->context,
filter->user_data_free_func,
filter->user_data);
}
g_main_context_unref (filter->context);
g_free (filter);
}
/* requires CONNECTION_LOCK */
static FilterData **
copy_filter_list (GPtrArray *filters)
{
FilterData **copy;
guint n;
copy = g_new (FilterData *, filters->len + 1);
for (n = 0; n < filters->len; n++)
{
copy[n] = filters->pdata[n];
copy[n]->ref_count++;
}
copy[n] = NULL;
return copy;
}
/* requires CONNECTION_LOCK */
static void
free_filter_list (FilterData **filters)
{
guint n;
for (n = 0; filters[n]; n++)
{
filters[n]->ref_count--;
if (filters[n]->ref_count == 0)
filter_data_destroy (filters[n], FALSE);
}
g_free (filters);
}
/* Called in GDBusWorker's thread - we must not block - with no lock held */
static void
on_worker_message_received (GDBusWorker *worker,
GDBusMessage *message,
gpointer user_data)
{
GDBusConnection *connection;
FilterData **filters;
guint n;
gboolean alive;
G_LOCK (message_bus_lock);
alive = g_hash_table_contains (alive_connections, user_data);
if (!alive)
{
G_UNLOCK (message_bus_lock);
return;
}
connection = G_DBUS_CONNECTION (user_data);
g_object_ref (connection);
G_UNLOCK (message_bus_lock);
//g_debug ("in on_worker_message_received");
g_object_ref (message);
g_dbus_message_lock (message);
//g_debug ("boo ref_count = %d %p %p", G_OBJECT (connection)->ref_count, connection, connection->worker);
/* First collect the set of callback functions */
CONNECTION_LOCK (connection);
filters = copy_filter_list (connection->filters);
CONNECTION_UNLOCK (connection);
/* then call the filters in order (without holding the lock) */
for (n = 0; filters[n]; n++)
{
message = filters[n]->filter_function (connection,
message,
TRUE,
filters[n]->user_data);
if (message == NULL)
break;
g_dbus_message_lock (message);
}
CONNECTION_LOCK (connection);
free_filter_list (filters);
CONNECTION_UNLOCK (connection);
/* Standard dispatch unless the filter ate the message - no need to
* do anything if the message was altered
*/
if (message != NULL)
{
GDBusMessageType message_type;
message_type = g_dbus_message_get_message_type (message);
if (message_type == G_DBUS_MESSAGE_TYPE_METHOD_RETURN || message_type == G_DBUS_MESSAGE_TYPE_ERROR)
{
guint32 reply_serial;
GTask *task;
reply_serial = g_dbus_message_get_reply_serial (message);
CONNECTION_LOCK (connection);
task = g_hash_table_lookup (connection->map_method_serial_to_task,
GUINT_TO_POINTER (reply_serial));
if (task != NULL)
{
/* This removes @task from @map_method_serial_to_task. */
//g_debug ("delivering reply/error for serial %d for %p", reply_serial, connection);
send_message_data_deliver_reply_unlocked (task, message);
}
else
{
//g_debug ("message reply/error for serial %d but no SendMessageData found for %p", reply_serial, connection);
}
CONNECTION_UNLOCK (connection);
}
else if (message_type == G_DBUS_MESSAGE_TYPE_SIGNAL)
{
CONNECTION_LOCK (connection);
distribute_signals (connection, message);
CONNECTION_UNLOCK (connection);
}
else if (message_type == G_DBUS_MESSAGE_TYPE_METHOD_CALL)
{
CONNECTION_LOCK (connection);
distribute_method_call (connection, message);
CONNECTION_UNLOCK (connection);
}
}
if (message != NULL)
g_object_unref (message);
g_object_unref (connection);
}
/* Called in GDBusWorker's thread, lock is not held */
static GDBusMessage *
on_worker_message_about_to_be_sent (GDBusWorker *worker,
GDBusMessage *message,
gpointer user_data)
{
GDBusConnection *connection;
FilterData **filters;
guint n;
gboolean alive;
G_LOCK (message_bus_lock);
alive = g_hash_table_contains (alive_connections, user_data);
if (!alive)
{
G_UNLOCK (message_bus_lock);
return message;
}
connection = G_DBUS_CONNECTION (user_data);
g_object_ref (connection);
G_UNLOCK (message_bus_lock);
//g_debug ("in on_worker_message_about_to_be_sent");
/* First collect the set of callback functions */
CONNECTION_LOCK (connection);
filters = copy_filter_list (connection->filters);
CONNECTION_UNLOCK (connection);
/* then call the filters in order (without holding the lock) */
for (n = 0; filters[n]; n++)
{
g_dbus_message_lock (message);
message = filters[n]->filter_function (connection,
message,
FALSE,
filters[n]->user_data);
if (message == NULL)
break;
}
CONNECTION_LOCK (connection);
free_filter_list (filters);
CONNECTION_UNLOCK (connection);
g_object_unref (connection);
return message;
}
/* called with connection lock held, in GDBusWorker thread
* @key, @value and @user_data are (transfer none) */
static gboolean
cancel_method_on_close (gpointer key, gpointer value, gpointer user_data)
{
GTask *task = value;
SendMessageData *data = g_task_get_task_data (task);
if (data->delivered)
return FALSE;
g_task_return_new_error_literal (task,
G_IO_ERROR,
G_IO_ERROR_CLOSED,
_("The connection is closed"));
/* Ask send_message_with_reply_cleanup not to remove the element from the
* hash table - we're in the middle of a foreach; that would be unsafe.
* Instead, return TRUE from this function so that it gets removed safely.
*/
send_message_with_reply_cleanup (task, FALSE);
return TRUE;
}
/* Called in GDBusWorker's thread - we must not block - without lock held */
static void
on_worker_closed (GDBusWorker *worker,
gboolean remote_peer_vanished,
GError *error,
gpointer user_data)
{
GDBusConnection *connection;
gboolean alive;
guint old_atomic_flags;
G_LOCK (message_bus_lock);
alive = g_hash_table_contains (alive_connections, user_data);
if (!alive)
{
G_UNLOCK (message_bus_lock);
return;
}
connection = G_DBUS_CONNECTION (user_data);
g_object_ref (connection);
G_UNLOCK (message_bus_lock);
//g_debug ("in on_worker_closed: %s", error->message);
CONNECTION_LOCK (connection);
/* Even though this is atomic, we do it inside the lock to avoid breaking
* assumptions in remove_match_rule(). We'd need the lock in a moment
* anyway, so, no loss.
*/
old_atomic_flags = g_atomic_int_or (&connection->atomic_flags, FLAG_CLOSED);
if (!(old_atomic_flags & FLAG_CLOSED))
{
g_hash_table_foreach_remove (connection->map_method_serial_to_task, cancel_method_on_close, NULL);
schedule_closed_unlocked (connection, remote_peer_vanished, error);
}
CONNECTION_UNLOCK (connection);
g_object_unref (connection);
}
/* ---------------------------------------------------------------------------------------------------- */
/* Determines the biggest set of capabilities we can support on this
* connection.
*
* Called with the init_lock held.
*/
static GDBusCapabilityFlags
get_offered_capabilities_max (GDBusConnection *connection)
{
GDBusCapabilityFlags ret;
ret = G_DBUS_CAPABILITY_FLAGS_NONE;
#ifdef G_OS_UNIX
if (G_IS_UNIX_CONNECTION (connection->stream))
ret |= G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING;
#endif
return ret;
}
/* Called in a user thread, lock is not held */
static gboolean
initable_init (GInitable *initable,
GCancellable *cancellable,
GError **error)
{
GDBusConnection *connection = G_DBUS_CONNECTION (initable);
gboolean ret;
/* This method needs to be idempotent to work with the singleton
* pattern. See the docs for g_initable_init(). We implement this by
* locking.
*
* Unfortunately we can't use the main lock since the on_worker_*()
* callbacks above needs the lock during initialization (for message
* bus connections we do a synchronous Hello() call on the bus).
*/
g_mutex_lock (&connection->init_lock);
ret = FALSE;
/* Make this a no-op if we're already initialized (successfully or
* unsuccessfully)
*/
if ((g_atomic_int_get (&connection->atomic_flags) & FLAG_INITIALIZED))
{
ret = (connection->initialization_error == NULL);
goto out;
}
/* Because of init_lock, we can't get here twice in different threads */
g_assert (connection->initialization_error == NULL);
/* The user can pass multiple (but mutally exclusive) construct
* properties:
*
* - stream (of type GIOStream)
* - address (of type gchar*)
*
* At the end of the day we end up with a non-NULL GIOStream
* object in connection->stream.
*/
if (connection->address != NULL)
{
g_assert (connection->stream == NULL);
if ((connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER) ||
(connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_ALLOW_ANONYMOUS) ||
(connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_REQUIRE_SAME_USER))
{
g_set_error_literal (&connection->initialization_error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Unsupported flags encountered when constructing a client-side connection"));
goto out;
}
connection->stream = g_dbus_address_get_stream_sync (connection->address,
NULL, /* TODO: out_guid */
cancellable,
&connection->initialization_error);
if (connection->stream == NULL)
goto out;
}
else if (connection->stream != NULL)
{
/* nothing to do */
}
else
{
g_assert_not_reached ();
}
/* Authenticate the connection */
if (connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER)
{
g_assert (!(connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT));
g_assert (connection->guid != NULL);
connection->auth = _g_dbus_auth_new (connection->stream);
if (!_g_dbus_auth_run_server (connection->auth,
connection->authentication_observer,
connection->guid,
(connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_ALLOW_ANONYMOUS),
(connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_REQUIRE_SAME_USER),
get_offered_capabilities_max (connection),
&connection->capabilities,
&connection->credentials,
cancellable,
&connection->initialization_error))
goto out;
}
else if (connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT)
{
g_assert (!(connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER));
g_assert (connection->guid == NULL);
connection->auth = _g_dbus_auth_new (connection->stream);
connection->guid = _g_dbus_auth_run_client (connection->auth,
connection->authentication_observer,
connection->flags,
get_offered_capabilities_max (connection),
&connection->capabilities,
cancellable,
&connection->initialization_error);
if (connection->guid == NULL)
goto out;
}
if (connection->authentication_observer != NULL)
{
g_object_unref (connection->authentication_observer);
connection->authentication_observer = NULL;
}
//g_output_stream_flush (G_SOCKET_CONNECTION (connection->stream)
//g_debug ("haz unix fd passing powers: %d", connection->capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING);
#ifdef G_OS_UNIX
/* We want all IO operations to be non-blocking since they happen in
* the worker thread which is shared by _all_ connections.
*/
if (G_IS_SOCKET_CONNECTION (connection->stream))
{
g_socket_set_blocking (g_socket_connection_get_socket (G_SOCKET_CONNECTION (connection->stream)), FALSE);
}
#endif
G_LOCK (message_bus_lock);
if (alive_connections == NULL)
alive_connections = g_hash_table_new (g_direct_hash, g_direct_equal);
g_hash_table_add (alive_connections, connection);
G_UNLOCK (message_bus_lock);
connection->worker = _g_dbus_worker_new (connection->stream,
connection->capabilities,
((connection->flags & G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING) != 0),
on_worker_message_received,
on_worker_message_about_to_be_sent,
on_worker_closed,
connection);
/* if a bus connection, call org.freedesktop.DBus.Hello - this is how we're getting a name */
if (connection->flags & G_DBUS_CONNECTION_FLAGS_MESSAGE_BUS_CONNECTION)
{
GVariant *hello_result;
/* we could lift this restriction by adding code in gdbusprivate.c */
if (connection->flags & G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING)
{
g_set_error_literal (&connection->initialization_error,
G_IO_ERROR,
G_IO_ERROR_FAILED,
"Cannot use DELAY_MESSAGE_PROCESSING with MESSAGE_BUS_CONNECTION");
goto out;
}
hello_result = g_dbus_connection_call_sync (connection,
"org.freedesktop.DBus", /* name */
"/org/freedesktop/DBus", /* path */
"org.freedesktop.DBus", /* interface */
"Hello",
NULL, /* parameters */
G_VARIANT_TYPE ("(s)"),
CALL_FLAGS_INITIALIZING,
-1,
NULL, /* TODO: cancellable */
&connection->initialization_error);
if (hello_result == NULL)
goto out;
g_variant_get (hello_result, "(s)", &connection->bus_unique_name);
g_variant_unref (hello_result);
//g_debug ("unique name is '%s'", connection->bus_unique_name);
}
ret = TRUE;
out:
if (!ret)
{
g_assert (connection->initialization_error != NULL);
g_propagate_error (error, g_error_copy (connection->initialization_error));
}
/* Don't cache canceled errors. Otherwise other concurrent users of the same connection
* object will be canceled as well. */
if (g_error_matches (connection->initialization_error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
{
if (connection->worker != NULL)
{
_g_dbus_worker_stop (connection->worker);
connection->worker = NULL;
if (alive_connections != NULL)
g_warn_if_fail (g_hash_table_remove (alive_connections, connection));
}
g_clear_error (&connection->initialization_error);
g_clear_object (&connection->stream);
g_clear_object (&connection->auth);
g_clear_object (&connection->credentials);
g_clear_pointer (&connection->guid, g_free);
connection->capabilities = 0;
}
else
g_atomic_int_or (&connection->atomic_flags, FLAG_INITIALIZED);
g_mutex_unlock (&connection->init_lock);
return ret;
}
static void
initable_iface_init (GInitableIface *initable_iface)
{
initable_iface->init = initable_init;
}
/* ---------------------------------------------------------------------------------------------------- */
static void
async_initable_iface_init (GAsyncInitableIface *async_initable_iface)
{
/* Use default */
}
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_dbus_connection_new:
* @stream: a #GIOStream
* @guid: (nullable): the GUID to use if authenticating as a server or %NULL
* @flags: flags describing how to make the connection
* @observer: (nullable): a #GDBusAuthObserver or %NULL
* @cancellable: (nullable): a #GCancellable or %NULL
* @callback: a #GAsyncReadyCallback to call when the request is satisfied
* @user_data: the data to pass to @callback
*
* Asynchronously sets up a D-Bus connection for exchanging D-Bus messages
* with the end represented by @stream.
*
* If @stream is a #GSocketConnection, then the corresponding #GSocket
* will be put into non-blocking mode.
*
* The D-Bus connection will interact with @stream from a worker thread.
* As a result, the caller should not interact with @stream after this
* method has been called, except by calling g_object_unref() on it.
*
* If @observer is not %NULL it may be used to control the
* authentication process.
*
* When the operation is finished, @callback will be invoked. You can
* then call g_dbus_connection_new_finish() to get the result of the
* operation.
*
* This is an asynchronous failable constructor. See
* g_dbus_connection_new_sync() for the synchronous
* version.
*
* Since: 2.26
*/
void
g_dbus_connection_new (GIOStream *stream,
const gchar *guid,
GDBusConnectionFlags flags,
GDBusAuthObserver *observer,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
_g_dbus_initialize ();
g_return_if_fail (G_IS_IO_STREAM (stream));
g_return_if_fail ((flags & ~G_DBUS_CONNECTION_FLAGS_ALL) == 0);
g_async_initable_new_async (G_TYPE_DBUS_CONNECTION,
G_PRIORITY_DEFAULT,
cancellable,
callback,
user_data,
"stream", stream,
"guid", guid,
"flags", flags,
"authentication-observer", observer,
NULL);
}
/**
* g_dbus_connection_new_finish:
* @res: a #GAsyncResult obtained from the #GAsyncReadyCallback
* passed to g_dbus_connection_new().
* @error: return location for error or %NULL
*
* Finishes an operation started with g_dbus_connection_new().
*
* Returns: (transfer full): a #GDBusConnection or %NULL if @error is set. Free
* with g_object_unref().
*
* Since: 2.26
*/
GDBusConnection *
g_dbus_connection_new_finish (GAsyncResult *res,
GError **error)
{
GObject *object;
GObject *source_object;
g_return_val_if_fail (G_IS_ASYNC_RESULT (res), NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
source_object = g_async_result_get_source_object (res);
g_assert (source_object != NULL);
object = g_async_initable_new_finish (G_ASYNC_INITABLE (source_object),
res,
error);
g_object_unref (source_object);
if (object != NULL)
return G_DBUS_CONNECTION (object);
else
return NULL;
}
/**
* g_dbus_connection_new_sync:
* @stream: a #GIOStream
* @guid: (nullable): the GUID to use if authenticating as a server or %NULL
* @flags: flags describing how to make the connection
* @observer: (nullable): a #GDBusAuthObserver or %NULL
* @cancellable: (nullable): a #GCancellable or %NULL
* @error: return location for error or %NULL
*
* Synchronously sets up a D-Bus connection for exchanging D-Bus messages
* with the end represented by @stream.
*
* If @stream is a #GSocketConnection, then the corresponding #GSocket
* will be put into non-blocking mode.
*
* The D-Bus connection will interact with @stream from a worker thread.
* As a result, the caller should not interact with @stream after this
* method has been called, except by calling g_object_unref() on it.
*
* If @observer is not %NULL it may be used to control the
* authentication process.
*
* This is a synchronous failable constructor. See
* g_dbus_connection_new() for the asynchronous version.
*
* Returns: (transfer full): a #GDBusConnection or %NULL if @error is set.
* Free with g_object_unref().
*
* Since: 2.26
*/
GDBusConnection *
g_dbus_connection_new_sync (GIOStream *stream,
const gchar *guid,
GDBusConnectionFlags flags,
GDBusAuthObserver *observer,
GCancellable *cancellable,
GError **error)
{
_g_dbus_initialize ();
g_return_val_if_fail (G_IS_IO_STREAM (stream), NULL);
g_return_val_if_fail ((flags & ~G_DBUS_CONNECTION_FLAGS_ALL) == 0, NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
return g_initable_new (G_TYPE_DBUS_CONNECTION,
cancellable,
error,
"stream", stream,
"guid", guid,
"flags", flags,
"authentication-observer", observer,
NULL);
}
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_dbus_connection_new_for_address:
* @address: a D-Bus address
* @flags: flags describing how to make the connection
* @observer: (nullable): a #GDBusAuthObserver or %NULL
* @cancellable: (nullable): a #GCancellable or %NULL
* @callback: a #GAsyncReadyCallback to call when the request is satisfied
* @user_data: the data to pass to @callback
*
* Asynchronously connects and sets up a D-Bus client connection for
* exchanging D-Bus messages with an endpoint specified by @address
* which must be in the
* [D-Bus address format](https://dbus.freedesktop.org/doc/dbus-specification.html#addresses).
*
* This constructor can only be used to initiate client-side
* connections - use g_dbus_connection_new() if you need to act as the
* server. In particular, @flags cannot contain the
* %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER,
* %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_ALLOW_ANONYMOUS or
* %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_REQUIRE_SAME_USER flags.
*
* When the operation is finished, @callback will be invoked. You can
* then call g_dbus_connection_new_for_address_finish() to get the result of
* the operation.
*
* If @observer is not %NULL it may be used to control the
* authentication process.
*
* This is an asynchronous failable constructor. See
* g_dbus_connection_new_for_address_sync() for the synchronous
* version.
*
* Since: 2.26
*/
void
g_dbus_connection_new_for_address (const gchar *address,
GDBusConnectionFlags flags,
GDBusAuthObserver *observer,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
_g_dbus_initialize ();
g_return_if_fail (address != NULL);
g_return_if_fail ((flags & ~G_DBUS_CONNECTION_FLAGS_ALL) == 0);
g_async_initable_new_async (G_TYPE_DBUS_CONNECTION,
G_PRIORITY_DEFAULT,
cancellable,
callback,
user_data,
"address", address,
"flags", flags,
"authentication-observer", observer,
NULL);
}
/**
* g_dbus_connection_new_for_address_finish:
* @res: a #GAsyncResult obtained from the #GAsyncReadyCallback passed
* to g_dbus_connection_new()
* @error: return location for error or %NULL
*
* Finishes an operation started with g_dbus_connection_new_for_address().
*
* Returns: (transfer full): a #GDBusConnection or %NULL if @error is set.
* Free with g_object_unref().
*
* Since: 2.26
*/
GDBusConnection *
g_dbus_connection_new_for_address_finish (GAsyncResult *res,
GError **error)
{
GObject *object;
GObject *source_object;
g_return_val_if_fail (G_IS_ASYNC_RESULT (res), NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
source_object = g_async_result_get_source_object (res);
g_assert (source_object != NULL);
object = g_async_initable_new_finish (G_ASYNC_INITABLE (source_object),
res,
error);
g_object_unref (source_object);
if (object != NULL)
return G_DBUS_CONNECTION (object);
else
return NULL;
}
/**
* g_dbus_connection_new_for_address_sync:
* @address: a D-Bus address
* @flags: flags describing how to make the connection
* @observer: (nullable): a #GDBusAuthObserver or %NULL
* @cancellable: (nullable): a #GCancellable or %NULL
* @error: return location for error or %NULL
*
* Synchronously connects and sets up a D-Bus client connection for
* exchanging D-Bus messages with an endpoint specified by @address
* which must be in the
* [D-Bus address format](https://dbus.freedesktop.org/doc/dbus-specification.html#addresses).
*
* This constructor can only be used to initiate client-side
* connections - use g_dbus_connection_new_sync() if you need to act
* as the server. In particular, @flags cannot contain the
* %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER,
* %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_ALLOW_ANONYMOUS or
* %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_REQUIRE_SAME_USER flags.
*
* This is a synchronous failable constructor. See
* g_dbus_connection_new_for_address() for the asynchronous version.
*
* If @observer is not %NULL it may be used to control the
* authentication process.
*
* Returns: (transfer full): a #GDBusConnection or %NULL if @error is set.
* Free with g_object_unref().
*
* Since: 2.26
*/
GDBusConnection *
g_dbus_connection_new_for_address_sync (const gchar *address,
GDBusConnectionFlags flags,
GDBusAuthObserver *observer,
GCancellable *cancellable,
GError **error)
{
_g_dbus_initialize ();
g_return_val_if_fail (address != NULL, NULL);
g_return_val_if_fail ((flags & ~G_DBUS_CONNECTION_FLAGS_ALL) == 0, NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
return g_initable_new (G_TYPE_DBUS_CONNECTION,
cancellable,
error,
"address", address,
"flags", flags,
"authentication-observer", observer,
NULL);
}
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_dbus_connection_set_exit_on_close:
* @connection: a #GDBusConnection
* @exit_on_close: whether the process should be terminated
* when @connection is closed by the remote peer
*
* Sets whether the process should be terminated when @connection is
* closed by the remote peer. See #GDBusConnection:exit-on-close for
* more details.
*
* Note that this function should be used with care. Most modern UNIX
* desktops tie the notion of a user session with the session bus, and expect
* all of a user's applications to quit when their bus connection goes away.
* If you are setting @exit_on_close to %FALSE for the shared session
* bus connection, you should make sure that your application exits
* when the user session ends.
*
* Since: 2.26
*/
void
g_dbus_connection_set_exit_on_close (GDBusConnection *connection,
gboolean exit_on_close)
{
g_return_if_fail (G_IS_DBUS_CONNECTION (connection));
if (exit_on_close)
g_atomic_int_or (&connection->atomic_flags, FLAG_EXIT_ON_CLOSE);
else
g_atomic_int_and (&connection->atomic_flags, ~FLAG_EXIT_ON_CLOSE);
}
/**
* g_dbus_connection_get_exit_on_close:
* @connection: a #GDBusConnection
*
* Gets whether the process is terminated when @connection is
* closed by the remote peer. See
* #GDBusConnection:exit-on-close for more details.
*
* Returns: whether the process is terminated when @connection is
* closed by the remote peer
*
* Since: 2.26
*/
gboolean
g_dbus_connection_get_exit_on_close (GDBusConnection *connection)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), FALSE);
if (g_atomic_int_get (&connection->atomic_flags) & FLAG_EXIT_ON_CLOSE)
return TRUE;
else
return FALSE;
}
/**
* g_dbus_connection_get_guid:
* @connection: a #GDBusConnection
*
* The GUID of the peer performing the role of server when
* authenticating. See #GDBusConnection:guid for more details.
*
* Returns: (not nullable): The GUID. Do not free this string, it is owned by
* @connection.
*
* Since: 2.26
*/
const gchar *
g_dbus_connection_get_guid (GDBusConnection *connection)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), NULL);
return connection->guid;
}
/**
* g_dbus_connection_get_unique_name:
* @connection: a #GDBusConnection
*
* Gets the unique name of @connection as assigned by the message
* bus. This can also be used to figure out if @connection is a
* message bus connection.
*
* Returns: (nullable): the unique name or %NULL if @connection is not a message
* bus connection. Do not free this string, it is owned by
* @connection.
*
* Since: 2.26
*/
const gchar *
g_dbus_connection_get_unique_name (GDBusConnection *connection)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), NULL);
/* do not use g_return_val_if_fail(), we want the memory barrier */
if (!check_initialized (connection))
return NULL;
return connection->bus_unique_name;
}
/**
* g_dbus_connection_get_peer_credentials:
* @connection: a #GDBusConnection
*
* Gets the credentials of the authenticated peer. This will always
* return %NULL unless @connection acted as a server
* (e.g. %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER was passed)
* when set up and the client passed credentials as part of the
* authentication process.
*
* In a message bus setup, the message bus is always the server and
* each application is a client. So this method will always return
* %NULL for message bus clients.
*
* Returns: (transfer none) (nullable): a #GCredentials or %NULL if not
* available. Do not free this object, it is owned by @connection.
*
* Since: 2.26
*/
GCredentials *
g_dbus_connection_get_peer_credentials (GDBusConnection *connection)
{
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), NULL);
/* do not use g_return_val_if_fail(), we want the memory barrier */
if (!check_initialized (connection))
return NULL;
return connection->credentials;
}
/* ---------------------------------------------------------------------------------------------------- */
static guint _global_filter_id = 1; /* (atomic) */
/**
* g_dbus_connection_add_filter:
* @connection: a #GDBusConnection
* @filter_function: a filter function
* @user_data: user data to pass to @filter_function
* @user_data_free_func: function to free @user_data with when filter
* is removed or %NULL
*
* Adds a message filter. Filters are handlers that are run on all
* incoming and outgoing messages, prior to standard dispatch. Filters
* are run in the order that they were added. The same handler can be
* added as a filter more than once, in which case it will be run more
* than once. Filters added during a filter callback won't be run on
* the message being processed. Filter functions are allowed to modify
* and even drop messages.
*
* Note that filters are run in a dedicated message handling thread so
* they can't block and, generally, can't do anything but signal a
* worker thread. Also note that filters are rarely needed - use API
* such as g_dbus_connection_send_message_with_reply(),
* g_dbus_connection_signal_subscribe() or g_dbus_connection_call() instead.
*
* If a filter consumes an incoming message the message is not
* dispatched anywhere else - not even the standard dispatch machinery
* (that API such as g_dbus_connection_signal_subscribe() and
* g_dbus_connection_send_message_with_reply() relies on) will see the
* message. Similarly, if a filter consumes an outgoing message, the
* message will not be sent to the other peer.
*
* If @user_data_free_func is non-%NULL, it will be called (in the
* thread-default main context of the thread you are calling this
* method from) at some point after @user_data is no longer
* needed. (It is not guaranteed to be called synchronously when the
* filter is removed, and may be called after @connection has been
* destroyed.)
*
* Returns: a filter identifier that can be used with
* g_dbus_connection_remove_filter()
*
* Since: 2.26
*/
guint
g_dbus_connection_add_filter (GDBusConnection *connection,
GDBusMessageFilterFunction filter_function,
gpointer user_data,
GDestroyNotify user_data_free_func)
{
FilterData *data;
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), 0);
g_return_val_if_fail (filter_function != NULL, 0);
g_return_val_if_fail (check_initialized (connection), 0);
CONNECTION_LOCK (connection);
data = g_new0 (FilterData, 1);
data->id = (guint) g_atomic_int_add (&_global_filter_id, 1); /* TODO: overflow etc. */
data->ref_count = 1;
data->filter_function = filter_function;
data->user_data = user_data;
data->user_data_free_func = user_data_free_func;
data->context = g_main_context_ref_thread_default ();
g_ptr_array_add (connection->filters, data);
CONNECTION_UNLOCK (connection);
return data->id;
}
/* only called from finalize(), removes all filters */
static void
purge_all_filters (GDBusConnection *connection)
{
guint n;
for (n = 0; n < connection->filters->len; n++)
filter_data_destroy (connection->filters->pdata[n], FALSE);
}
/**
* g_dbus_connection_remove_filter:
* @connection: a #GDBusConnection
* @filter_id: an identifier obtained from g_dbus_connection_add_filter()
*
* Removes a filter.
*
* Note that since filters run in a different thread, there is a race
* condition where it is possible that the filter will be running even
* after calling g_dbus_connection_remove_filter(), so you cannot just
* free data that the filter might be using. Instead, you should pass
* a #GDestroyNotify to g_dbus_connection_add_filter(), which will be
* called when it is guaranteed that the data is no longer needed.
*
* Since: 2.26
*/
void
g_dbus_connection_remove_filter (GDBusConnection *connection,
guint filter_id)
{
guint n;
gboolean found;
FilterData *to_destroy;
g_return_if_fail (G_IS_DBUS_CONNECTION (connection));
g_return_if_fail (check_initialized (connection));
CONNECTION_LOCK (connection);
found = FALSE;
to_destroy = NULL;
for (n = 0; n < connection->filters->len; n++)
{
FilterData *data = connection->filters->pdata[n];
if (data->id == filter_id)
{
found = TRUE;
g_ptr_array_remove_index (connection->filters, n);
data->ref_count--;
if (data->ref_count == 0)
to_destroy = data;
break;
}
}
CONNECTION_UNLOCK (connection);
/* do free without holding lock */
if (to_destroy != NULL)
filter_data_destroy (to_destroy, TRUE);
else if (!found)
{
g_warning ("g_dbus_connection_remove_filter: No filter found for filter_id %d", filter_id);
}
}
/* ---------------------------------------------------------------------------------------------------- */
typedef struct
{
gchar *rule;
gchar *sender;
gchar *sender_unique_name; /* if sender is unique or org.freedesktop.DBus, then that name... otherwise blank */
gchar *interface_name;
gchar *member;
gchar *object_path;
gchar *arg0;
GDBusSignalFlags flags;
GPtrArray *subscribers; /* (owned) (element-type SignalSubscriber) */
} SignalData;
static void
signal_data_free (SignalData *signal_data)
{
g_free (signal_data->rule);
g_free (signal_data->sender);
g_free (signal_data->sender_unique_name);
g_free (signal_data->interface_name);
g_free (signal_data->member);
g_free (signal_data->object_path);
g_free (signal_data->arg0);
g_ptr_array_unref (signal_data->subscribers);
g_free (signal_data);
}
typedef struct
{
/* All fields are immutable after construction. */
gatomicrefcount ref_count;
GDBusSignalCallback callback;
gpointer user_data;
GDestroyNotify user_data_free_func;
guint id;
GMainContext *context;
} SignalSubscriber;
static SignalSubscriber *
signal_subscriber_ref (SignalSubscriber *subscriber)
{
g_atomic_ref_count_inc (&subscriber->ref_count);
return subscriber;
}
static void
signal_subscriber_unref (SignalSubscriber *subscriber)
{
if (g_atomic_ref_count_dec (&subscriber->ref_count))
{
/* Destroy the user data. It doesn’t matter which thread
* signal_subscriber_unref() is called in (or whether it’s called with a
* lock held), as call_destroy_notify() always defers to the next
* #GMainContext iteration. */
call_destroy_notify (subscriber->context,
subscriber->user_data_free_func,
subscriber->user_data);
g_main_context_unref (subscriber->context);
g_free (subscriber);
}
}
static gchar *
args_to_rule (const gchar *sender,
const gchar *interface_name,
const gchar *member,
const gchar *object_path,
const gchar *arg0,
GDBusSignalFlags flags)
{
GString *rule;
rule = g_string_new ("type='signal'");
if (flags & G_DBUS_SIGNAL_FLAGS_NO_MATCH_RULE)
g_string_prepend_c (rule, '-');
if (sender != NULL)
g_string_append_printf (rule, ",sender='%s'", sender);
if (interface_name != NULL)
g_string_append_printf (rule, ",interface='%s'", interface_name);
if (member != NULL)
g_string_append_printf (rule, ",member='%s'", member);
if (object_path != NULL)
g_string_append_printf (rule, ",path='%s'", object_path);
if (arg0 != NULL)
{
if (flags & G_DBUS_SIGNAL_FLAGS_MATCH_ARG0_PATH)
g_string_append_printf (rule, ",arg0path='%s'", arg0);
else if (flags & G_DBUS_SIGNAL_FLAGS_MATCH_ARG0_NAMESPACE)
g_string_append_printf (rule, ",arg0namespace='%s'", arg0);
else
g_string_append_printf (rule, ",arg0='%s'", arg0);
}
return g_string_free (rule, FALSE);
}
static guint _global_subscriber_id = 1; /* (atomic) */
static guint _global_registration_id = 1; /* (atomic) */
static guint _global_subtree_registration_id = 1; /* (atomic) */
/* ---------------------------------------------------------------------------------------------------- */
/* Called in a user thread, lock is held */
static void
add_match_rule (GDBusConnection *connection,
const gchar *match_rule)
{
GError *error;
GDBusMessage *message;
if (match_rule[0] == '-')
return;
message = g_dbus_message_new_method_call ("org.freedesktop.DBus", /* name */
"/org/freedesktop/DBus", /* path */
"org.freedesktop.DBus", /* interface */
"AddMatch");
g_dbus_message_set_body (message, g_variant_new ("(s)", match_rule));
error = NULL;
if (!g_dbus_connection_send_message_unlocked (connection,
message,
G_DBUS_SEND_MESSAGE_FLAGS_NONE,
NULL,
&error))
{
g_critical ("Error while sending AddMatch() message: %s", error->message);
g_error_free (error);
}
g_object_unref (message);
}
/* ---------------------------------------------------------------------------------------------------- */
/* Called in a user thread, lock is held */
static void
remove_match_rule (GDBusConnection *connection,
const gchar *match_rule)
{
GError *error;
GDBusMessage *message;
if (match_rule[0] == '-')
return;
message = g_dbus_message_new_method_call ("org.freedesktop.DBus", /* name */
"/org/freedesktop/DBus", /* path */
"org.freedesktop.DBus", /* interface */
"RemoveMatch");
g_dbus_message_set_body (message, g_variant_new ("(s)", match_rule));
error = NULL;
if (!g_dbus_connection_send_message_unlocked (connection,
message,
G_DBUS_SEND_MESSAGE_FLAGS_NONE,
NULL,
&error))
{
/* If we could get G_IO_ERROR_CLOSED here, it wouldn't be reasonable to
* critical; but we're holding the lock, and our caller checked whether
* we were already closed, so we can't get that error.
*/
g_critical ("Error while sending RemoveMatch() message: %s", error->message);
g_error_free (error);
}
g_object_unref (message);
}
/* ---------------------------------------------------------------------------------------------------- */
static gboolean
is_signal_data_for_name_lost_or_acquired (SignalData *signal_data)
{
return g_strcmp0 (signal_data->sender_unique_name, "org.freedesktop.DBus") == 0 &&
g_strcmp0 (signal_data->interface_name, "org.freedesktop.DBus") == 0 &&
g_strcmp0 (signal_data->object_path, "/org/freedesktop/DBus") == 0 &&
(g_strcmp0 (signal_data->member, "NameLost") == 0 ||
g_strcmp0 (signal_data->member, "NameAcquired") == 0);
}
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_dbus_connection_signal_subscribe:
* @connection: a #GDBusConnection
* @sender: (nullable): sender name to match on (unique or well-known name)
* or %NULL to listen from all senders
* @interface_name: (nullable): D-Bus interface name to match on or %NULL to
* match on all interfaces
* @member: (nullable): D-Bus signal name to match on or %NULL to match on
* all signals
* @object_path: (nullable): object path to match on or %NULL to match on
* all object paths
* @arg0: (nullable): contents of first string argument to match on or %NULL
* to match on all kinds of arguments
* @flags: #GDBusSignalFlags describing how arg0 is used in subscribing to the
* signal
* @callback: callback to invoke when there is a signal matching the requested data
* @user_data: user data to pass to @callback
* @user_data_free_func: (nullable): function to free @user_data with when
* subscription is removed or %NULL
*
* Subscribes to signals on @connection and invokes @callback whenever
* the signal is received. Note that @callback will be invoked in the
* [thread-default main context][g-main-context-push-thread-default]
* of the thread you are calling this method from.
*
* If @connection is not a message bus connection, @sender must be
* %NULL.
*
* If @sender is a well-known name note that @callback is invoked with
* the unique name for the owner of @sender, not the well-known name
* as one would expect. This is because the message bus rewrites the
* name. As such, to avoid certain race conditions, users should be
* tracking the name owner of the well-known name and use that when
* processing the received signal.
*
* If one of %G_DBUS_SIGNAL_FLAGS_MATCH_ARG0_NAMESPACE or
* %G_DBUS_SIGNAL_FLAGS_MATCH_ARG0_PATH are given, @arg0 is
* interpreted as part of a namespace or path. The first argument
* of a signal is matched against that part as specified by D-Bus.
*
* If @user_data_free_func is non-%NULL, it will be called (in the
* thread-default main context of the thread you are calling this
* method from) at some point after @user_data is no longer
* needed. (It is not guaranteed to be called synchronously when the
* signal is unsubscribed from, and may be called after @connection
* has been destroyed.)
*
* As @callback is potentially invoked in a different thread from where it’s
* emitted, it’s possible for this to happen after
* g_dbus_connection_signal_unsubscribe() has been called in another thread.
* Due to this, @user_data should have a strong reference which is freed with
* @user_data_free_func, rather than pointing to data whose lifecycle is tied
* to the signal subscription. For example, if a #GObject is used to store the
* subscription ID from g_dbus_connection_signal_subscribe(), a strong reference
* to that #GObject must be passed to @user_data, and g_object_unref() passed to
* @user_data_free_func. You are responsible for breaking the resulting
* reference count cycle by explicitly unsubscribing from the signal when
* dropping the last external reference to the #GObject. Alternatively, a weak
* reference may be used.
*
* It is guaranteed that if you unsubscribe from a signal using
* g_dbus_connection_signal_unsubscribe() from the same thread which made the
* corresponding g_dbus_connection_signal_subscribe() call, @callback will not
* be invoked after g_dbus_connection_signal_unsubscribe() returns.
*
* The returned subscription identifier is an opaque value which is guaranteed
* to never be zero.
*
* This function can never fail.
*
* Returns: a subscription identifier that can be used with g_dbus_connection_signal_unsubscribe()
*
* Since: 2.26
*/
guint
g_dbus_connection_signal_subscribe (GDBusConnection *connection,
const gchar *sender,
const gchar *interface_name,
const gchar *member,
const gchar *object_path,
const gchar *arg0,