Unified network I/O

Unified network I/O — Posix style network input/output functions.

Synopsis




typedef     GnomeVFSSocket;
            GnomeVFSSocketImpl;
GnomeVFSResult (*GnomeVFSSocketReadFunc)    (gpointer connection,
                                             gpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_read_out,
                                             GnomeVFSCancellation *cancellation);
GnomeVFSResult (*GnomeVFSSocketWriteFunc)   (gpointer connection,
                                             gconstpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_written_out,
                                             GnomeVFSCancellation *cancellation);
void        (*GnomeVFSSocketCloseFunc)      (gpointer connection,
                                             GnomeVFSCancellation *cancellation);
GnomeVFSResult (*GnomeVFSSocketSetTimeoutFunc)
                                            (gpointer connection,
                                             GTimeVal *timeout,
                                             GnomeVFSCancellation *cancellation);
GnomeVFSSocket* gnome_vfs_socket_new        (GnomeVFSSocketImpl *impl,
                                             void *connection);
GnomeVFSResult gnome_vfs_socket_write       (GnomeVFSSocket *socket,
                                             gconstpointer buffer,
                                             int bytes,
                                             GnomeVFSFileSize *bytes_written,
                                             GnomeVFSCancellation *cancellation);
GnomeVFSResult gnome_vfs_socket_close       (GnomeVFSSocket *socket,
                                             GnomeVFSCancellation *cancellation);
GnomeVFSResult gnome_vfs_socket_read        (GnomeVFSSocket *socket,
                                             gpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_read,
                                             GnomeVFSCancellation *cancellation);
void        gnome_vfs_socket_free           (GnomeVFSSocket *socket);
GnomeVFSResult gnome_vfs_socket_set_timeout (GnomeVFSSocket *socket,
                                             GTimeVal *timeout,
                                             GnomeVFSCancellation *cancellation);

Description

The GnomeVFSSocket function family unifies network I/O through functions similar to the standard POSIX read/write functions. The main difference is that all operations are cancellable through the standard GnomeVFS cancellation mechanism and you can specify a maximum amount of time an operation may take through gnome_vfs_socket_set_timeout.

Details

GnomeVFSSocket

typedef struct GnomeVFSSocket GnomeVFSSocket;

An handle to a generic unbuffered socket connection established with gnome_vfs_socket_new().

The specifics of the underlying socket implementation are hidden inside the GnomeVFSSocketImpl passed on construction.

If you need buffered I/O, you will also have to create a GnomeVFSSocketBuffer.

GnomeVFSSocketImpl

typedef struct {
  GnomeVFSSocketReadFunc read;
  GnomeVFSSocketWriteFunc write;
  GnomeVFSSocketCloseFunc close;
  GnomeVFSSocketSetTimeoutFunc set_timeout;
} GnomeVFSSocketImpl;

An implementation of a generic socket (i.e. of GnomeVFSSocket) encapsulating the details of how socket I/O works.

Please refer to GnomeVFSSSL for a sample implementation of this interface.

GnomeVFSSocketReadFunc read; A GnomeVFSSocketReadFunc function used for reading from a socket.
GnomeVFSSocketWriteFunc write; A GnomeVFSSocketWriteFunc function used for writing to a socket.
GnomeVFSSocketCloseFunc close; A GnomeVFSSocketCloseFunc function used for closing an open socket.
GnomeVFSSocketSetTimeoutFunc set_timeout; A GnomeVFSSocketSetTimeoutFunc function used for setting a socket's timeout.

GnomeVFSSocketReadFunc ()

GnomeVFSResult (*GnomeVFSSocketReadFunc)    (gpointer connection,
                                             gpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_read_out,
                                             GnomeVFSCancellation *cancellation);

This is a generic prototype for a function that reads from a socket.

This function is implemented by a GnomeVFSSocketImpl, and it defines how data should be written to a buffer using the gnome_vfs_socket_read() function which hides the socket implementation details.

connection : The socket connection.
buffer : A connection buffer.
bytes : The bytes to read.
bytes_read_out : The bytes that were read (out).
cancellation : A cancellation handle that allows clients to cancel the read operation.
Returns : A GnomeVFSResult signalling the result of the read operation.

GnomeVFSSocketWriteFunc ()

GnomeVFSResult (*GnomeVFSSocketWriteFunc)   (gpointer connection,
                                             gconstpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_written_out,
                                             GnomeVFSCancellation *cancellation);

This is a generic prototype for a function that writes to a socket.

This function is implemented by a GnomeVFSSocketImpl, and it defines how data should be written to a buffer using the gnome_vfs_socket_write() function which hides the socket implementation details.

connection : The socket connection.
buffer : A connection buffer.
bytes : The bytes to write.
bytes_written_out : The bytes that were written.
cancellation : A cancellation handle that allows clients to cancel the write operation.
Returns : A GnomeVFSResult signalling the result of the write operation.

GnomeVFSSocketCloseFunc ()

void        (*GnomeVFSSocketCloseFunc)      (gpointer connection,
                                             GnomeVFSCancellation *cancellation);

This is a generic prototype for a function that closes a socket.

This function is implemented by a GnomeVFSSocketImpl, and it defines how an open socket that was previously opened by gnome_vfs_socket_new() should be closed using the gnome_vfs_socket_set_timeout() function which hides the socket implementation details.

connection :
cancellation : A cancellation handle that allows clients to cancel the write operation.

GnomeVFSSocketSetTimeoutFunc ()

GnomeVFSResult (*GnomeVFSSocketSetTimeoutFunc)
                                            (gpointer connection,
                                             GTimeVal *timeout,
                                             GnomeVFSCancellation *cancellation);

This is a generic prototype for a function that sets a socket timeout.

This function is implemented by a GnomeVFSSocketImpl, and it defines how a socket timeout should be set using should be closed by the gnome_vfs_socket_close() function which hides the socket implementation details.

connection :
timeout :
cancellation : A cancellation handle that allows clients to cancel the write operation.
Returns : A GnomeVFSResult signalling the result of the write operation.

gnome_vfs_socket_new ()

GnomeVFSSocket* gnome_vfs_socket_new        (GnomeVFSSocketImpl *impl,
                                             void *connection);

Creates a new GnomeVFSSocket using the specific implementation impl.

impl : an implementation of socket, e.g. GnomeVFSSSL.
connection : pointer to a connection object used by impl to track. state (the exact nature of connection varies from implementation to implementation).
Returns : a newly created socket.

gnome_vfs_socket_write ()

GnomeVFSResult gnome_vfs_socket_write       (GnomeVFSSocket *socket,
                                             gconstpointer buffer,
                                             int bytes,
                                             GnomeVFSFileSize *bytes_written,
                                             GnomeVFSCancellation *cancellation);

Write bytes bytes of data from buffer to socket.

socket : socket to write data to.
buffer : data to write to the socket.
bytes : number of bytes from buffer to write to socket.
bytes_written : pointer to a GnomeVFSFileSize, will contain the number of bytes actually written to the socket on return.
cancellation : optional cancellation object.
Returns : GnomeVFSResult indicating the success of the operation.

gnome_vfs_socket_close ()

GnomeVFSResult gnome_vfs_socket_close       (GnomeVFSSocket *socket,
                                             GnomeVFSCancellation *cancellation);

Close socket, freeing any resources it may be using.

socket : the socket to be closed.
cancellation : optional cancellation object.
Returns : GnomeVFSResult indicating the success of the operation.

gnome_vfs_socket_read ()

GnomeVFSResult gnome_vfs_socket_read        (GnomeVFSSocket *socket,
                                             gpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_read,
                                             GnomeVFSCancellation *cancellation);

Read bytes bytes of data from the socket into buffer.

socket : socket to read data from.
buffer : allocated buffer of at least bytes bytes to be read into.
bytes : number of bytes to read from socket into buffer.
bytes_read : pointer to a GnomeVFSFileSize, will contain the number of bytes actually read from the socket on return.
cancellation : optional cancellation object.
Returns : GnomeVFSResult indicating the success of the operation.

gnome_vfs_socket_free ()

void        gnome_vfs_socket_free           (GnomeVFSSocket *socket);

Frees the memory allocated for socket, but does not call any GnomeVFSSocketImpl function.

socket : The GnomeVFSSocket you want to free.

Since 2.8

gnome_vfs_socket_set_timeout ()

GnomeVFSResult gnome_vfs_socket_set_timeout (GnomeVFSSocket *socket,
                                             GTimeVal *timeout,
                                             GnomeVFSCancellation *cancellation);

Set a timeout of timeout. If timeout is NULL, following operations will block indefinitely).

Note if you set timeout to 0 (means tv_sec and tv_usec are both 0) every following operation will return immediately. (This can be used for polling.)

socket : socket to set the timeout of.
timeout : the timeout.
cancellation : optional cancellation object.
Returns : GnomeVFSResult indicating the success of the operation.

Since 2.8