GSocketListener

GSocketListener — Helper for accepting network client connections

Synopsis

                    GSocketListener;
GSocketListener *        g_socket_listener_new          (void);
gboolean            g_socket_listener_add_socket        (GSocketListener *listener,
                                                         GSocket *socket,
                                                         GObject *source_object,
                                                         GError **error);
gboolean            g_socket_listener_add_address       (GSocketListener *listener,
                                                         GSocketAddress *address,
                                                         GSocketType type,
                                                         GSocketProtocol protocol,
                                                         GObject *source_object,
                                                         GSocketAddress **effective_address,
                                                         GError **error);
gboolean            g_socket_listener_add_inet_port     (GSocketListener *listener,
                                                         guint16 port,
                                                         GObject *source_object,
                                                         GError **error);
guint16             g_socket_listener_add_any_inet_port (GSocketListener *listener,
                                                         GObject *source_object,
                                                         GError **error);
GSocketConnection *      g_socket_listener_accept       (GSocketListener *listener,
                                                         GObject **source_object,
                                                         GCancellable *cancellable,
                                                         GError **error);
void                g_socket_listener_accept_async      (GSocketListener *listener,
                                                         GCancellable *cancellable,
                                                         GAsyncReadyCallback callback,
                                                         gpointer user_data);
GSocketConnection *      g_socket_listener_accept_finish
                                                        (GSocketListener *listener,
                                                         GAsyncResult *result,
                                                         GObject **source_object,
                                                         GError **error);
GSocket *                g_socket_listener_accept_socket
                                                        (GSocketListener *listener,
                                                         GObject **source_object,
                                                         GCancellable *cancellable,
                                                         GError **error);
void                g_socket_listener_accept_socket_async
                                                        (GSocketListener *listener,
                                                         GCancellable *cancellable,
                                                         GAsyncReadyCallback callback,
                                                         gpointer user_data);
GSocket *                g_socket_listener_accept_socket_finish
                                                        (GSocketListener *listener,
                                                         GAsyncResult *result,
                                                         GObject **source_object,
                                                         GError **error);
void                g_socket_listener_close             (GSocketListener *listener);
void                g_socket_listener_set_backlog       (GSocketListener *listener,
                                                         int listen_backlog);

Object Hierarchy

  GObject
   +----GSocketListener
         +----GSocketService

Properties

  "listen-backlog"           gint                  : Read / Write / Construct

Description

A GSocketListener is an object that keeps track of a set of server sockets and helps you accept sockets from any of the socket, either sync or async.

If you want to implement a network server, also look at GSocketService and GThreadedSocketService which are subclass of GSocketListener that makes this even easier.

Details

GSocketListener

typedef struct _GSocketListener GSocketListener;


g_socket_listener_new ()

GSocketListener *        g_socket_listener_new          (void);

Creates a new GSocketListener with no sockets to listen for. New listeners can be added with e.g. g_socket_listener_add_address() or g_socket_listener_add_inet_port().

Returns :

a new GSocketListener.

Since 2.22


g_socket_listener_add_socket ()

gboolean            g_socket_listener_add_socket        (GSocketListener *listener,
                                                         GSocket *socket,
                                                         GObject *source_object,
                                                         GError **error);

Adds socket to the set of sockets that we try to accept new clients from. The socket must be bound to a local address and listened to.

source_object will be passed out in the various calls to accept to identify this particular source, which is useful if you're listening on multiple addresses and do different things depending on what address is connected to.

listener :

a GSocketListener

socket :

a listening GSocket

source_object :

Optional GObject identifying this source. [allow-none]

error :

GError for error reporting, or NULL to ignore.

Returns :

TRUE on success, FALSE on error.

Since 2.22


g_socket_listener_add_address ()

gboolean            g_socket_listener_add_address       (GSocketListener *listener,
                                                         GSocketAddress *address,
                                                         GSocketType type,
                                                         GSocketProtocol protocol,
                                                         GObject *source_object,
                                                         GSocketAddress **effective_address,
                                                         GError **error);

Creates a socket of type type and protocol protocol, binds it to address and adds it to the set of sockets we're accepting sockets from.

Note that adding an IPv6 address, depending on the platform, may or may not result in a listener that also accepts IPv4 connections. For more determinstic behaviour, see g_socket_listener_add_inet_port().

source_object will be passed out in the various calls to accept to identify this particular source, which is useful if you're listening on multiple addresses and do different things depending on what address is connected to.

If successful and effective_address is non-NULL then it will be set to the address that the binding actually occured at. This is helpful for determining the port number that was used for when requesting a binding to port 0 (ie: "any port"). This address, if requested, belongs to the caller and must be freed.

listener :

a GSocketListener

address :

a GSocketAddress

type :

a GSocketType

protocol :

a GSocketProtocol

source_object :

Optional GObject identifying this source. [allow-none]

effective_address :

location to store the address that was bound to, or NULL. [out][allow-none]

error :

GError for error reporting, or NULL to ignore.

Returns :

TRUE on success, FALSE on error.

Since 2.22


g_socket_listener_add_inet_port ()

gboolean            g_socket_listener_add_inet_port     (GSocketListener *listener,
                                                         guint16 port,
                                                         GObject *source_object,
                                                         GError **error);

Helper function for g_socket_listener_add_address() that creates a TCP/IP socket listening on IPv4 and IPv6 (if supported) on the specified port on all interfaces.

source_object will be passed out in the various calls to accept to identify this particular source, which is useful if you're listening on multiple addresses and do different things depending on what address is connected to.

listener :

a GSocketListener

port :

an IP port number (non-zero)

source_object :

Optional GObject identifying this source. [allow-none]

error :

GError for error reporting, or NULL to ignore.

Returns :

TRUE on success, FALSE on error.

Since 2.22


g_socket_listener_add_any_inet_port ()

guint16             g_socket_listener_add_any_inet_port (GSocketListener *listener,
                                                         GObject *source_object,
                                                         GError **error);

Listens for TCP connections on any available port number for both IPv6 and IPv4 (if each are available).

This is useful if you need to have a socket for incoming connections but don't care about the specific port number.

source_object will be passed out in the various calls to accept to identify this particular source, which is useful if you're listening on multiple addresses and do different things depending on what address is connected to.

listener :

a GSocketListener

source_object :

Optional GObject identifying this source. [allow-none]

error :

a GError location to store the error occuring, or NULL to ignore.

Returns :

the port number, or 0 in case of failure.

Since 2.24


g_socket_listener_accept ()

GSocketConnection *      g_socket_listener_accept       (GSocketListener *listener,
                                                         GObject **source_object,
                                                         GCancellable *cancellable,
                                                         GError **error);

Blocks waiting for a client to connect to any of the sockets added to the listener. Returns a GSocketConnection for the socket that was accepted.

If source_object is not NULL it will be filled out with the source object specified when the corresponding socket or address was added to the listener.

If cancellable is not NULL, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned.

listener :

a GSocketListener

source_object :

location where GObject pointer will be stored, or NULL. [out][transfer none][allow-none]

cancellable :

optional GCancellable object, NULL to ignore. [allow-none]

error :

GError for error reporting, or NULL to ignore.

Returns :

a GSocketConnection on success, NULL on error. [transfer full]

Since 2.22


g_socket_listener_accept_async ()

void                g_socket_listener_accept_async      (GSocketListener *listener,
                                                         GCancellable *cancellable,
                                                         GAsyncReadyCallback callback,
                                                         gpointer user_data);

This is the asynchronous version of g_socket_listener_accept().

When the operation is finished callback will be called. You can then call g_socket_listener_accept_socket() to get the result of the operation.

listener :

a GSocketListener

cancellable :

a GCancellable, or NULL. [allow-none]

callback :

a GAsyncReadyCallback. [scope async]

user_data :

user data for the callback. [closure]

Since 2.22


g_socket_listener_accept_finish ()

GSocketConnection *      g_socket_listener_accept_finish
                                                        (GSocketListener *listener,
                                                         GAsyncResult *result,
                                                         GObject **source_object,
                                                         GError **error);

Finishes an async accept operation. See g_socket_listener_accept_async()

listener :

a GSocketListener

result :

a GAsyncResult.

source_object :

Optional GObject identifying this source. [out][transfer none][allow-none]

error :

a GError location to store the error occuring, or NULL to ignore.

Returns :

a GSocketConnection on success, NULL on error. [transfer full]

Since 2.22


g_socket_listener_accept_socket ()

GSocket *                g_socket_listener_accept_socket
                                                        (GSocketListener *listener,
                                                         GObject **source_object,
                                                         GCancellable *cancellable,
                                                         GError **error);

Blocks waiting for a client to connect to any of the sockets added to the listener. Returns the GSocket that was accepted.

If you want to accept the high-level GSocketConnection, not a GSocket, which is often the case, then you should use g_socket_listener_accept() instead.

If source_object is not NULL it will be filled out with the source object specified when the corresponding socket or address was added to the listener.

If cancellable is not NULL, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned.

listener :

a GSocketListener

source_object :

location where GObject pointer will be stored, or NULL. [out][transfer none][allow-none]

cancellable :

optional GCancellable object, NULL to ignore. [allow-none]

error :

GError for error reporting, or NULL to ignore.

Returns :

a GSocket on success, NULL on error. [transfer full]

Since 2.22


g_socket_listener_accept_socket_async ()

void                g_socket_listener_accept_socket_async
                                                        (GSocketListener *listener,
                                                         GCancellable *cancellable,
                                                         GAsyncReadyCallback callback,
                                                         gpointer user_data);

This is the asynchronous version of g_socket_listener_accept_socket().

When the operation is finished callback will be called. You can then call g_socket_listener_accept_socket_finish() to get the result of the operation.

listener :

a GSocketListener

cancellable :

a GCancellable, or NULL. [allow-none]

callback :

a GAsyncReadyCallback. [scope async]

user_data :

user data for the callback. [closure]

Since 2.22


g_socket_listener_accept_socket_finish ()

GSocket *                g_socket_listener_accept_socket_finish
                                                        (GSocketListener *listener,
                                                         GAsyncResult *result,
                                                         GObject **source_object,
                                                         GError **error);

Finishes an async accept operation. See g_socket_listener_accept_socket_async()

listener :

a GSocketListener

result :

a GAsyncResult.

source_object :

Optional GObject identifying this source. [out][transfer none][allow-none]

error :

a GError location to store the error occuring, or NULL to ignore.

Returns :

a GSocket on success, NULL on error. [transfer full]

Since 2.22


g_socket_listener_close ()

void                g_socket_listener_close             (GSocketListener *listener);

Closes all the sockets in the listener.

listener :

a GSocketListener

Since 2.22


g_socket_listener_set_backlog ()

void                g_socket_listener_set_backlog       (GSocketListener *listener,
                                                         int listen_backlog);

Sets the listen backlog on the sockets in the listener.

See g_socket_set_listen_backlog() for details

listener :

a GSocketListener

listen_backlog :

an integer

Since 2.22

Property Details

The "listen-backlog" property

  "listen-backlog"           gint                  : Read / Write / Construct

outstanding connections in the listen queue.

Allowed values: [0,2000]

Default value: 10

See Also

GThreadedSocketService, GSocketService.