glib/gio/gasynchelper.c
Dan Winship 6181c7de36 GCancellable: add g_cancellable_create_source()
g_cancellable_create_source() returns a GSource that triggers when its
corresponding GCancellable is cancelled. This can be used with
g_source_add_child_source() to add cancellability to a source.

Port gasynchelper's FDSource to use this rather than doing its own
cancellable handling, and also fix up its callback argument order to
be more normal.

https://bugzilla.gnome.org/show_bug.cgi?id=634239
2010-11-26 15:07:28 -05:00

171 lines
4.2 KiB
C

/* GIO - GLib Input, Output and Streaming Library
*
* Copyright (C) 2006-2007 Red Hat, Inc.
*
* 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 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, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* Author: Alexander Larsson <alexl@redhat.com>
*/
#include "config.h"
#include "gasynchelper.h"
/**
* SECTION:gasynchelper
* @short_description: Asynchronous Helper Functions
* @include: gio/gio.h
* @see_also: #GAsyncReady
*
* Provides helper functions for asynchronous operations.
*
**/
/*************************************************************************
* fd source *
************************************************************************/
typedef struct
{
GSource source;
GPollFD pollfd;
} FDSource;
static gboolean
fd_source_prepare (GSource *source,
gint *timeout)
{
*timeout = -1;
return FALSE;
}
static gboolean
fd_source_check (GSource *source)
{
FDSource *fd_source = (FDSource *)source;
return fd_source->pollfd.revents != 0;
}
static gboolean
fd_source_dispatch (GSource *source,
GSourceFunc callback,
gpointer user_data)
{
GFDSourceFunc func = (GFDSourceFunc)callback;
FDSource *fd_source = (FDSource *)source;
g_warn_if_fail (func != NULL);
return (*func) (fd_source->pollfd.fd, fd_source->pollfd.revents, user_data);
}
static void
fd_source_finalize (GSource *source)
{
}
static gboolean
fd_source_closure_callback (int fd,
GIOCondition condition,
gpointer data)
{
GClosure *closure = data;
GValue params[2] = { { 0, }, { 0, } };
GValue result_value = { 0, };
gboolean result;
g_value_init (&result_value, G_TYPE_BOOLEAN);
g_value_init (&params[0], G_TYPE_INT);
g_value_set_int (&params[0], fd);
g_value_init (&params[1], G_TYPE_IO_CONDITION);
g_value_set_flags (&params[1], condition);
g_closure_invoke (closure, &result_value, 2, params, NULL);
result = g_value_get_boolean (&result_value);
g_value_unset (&result_value);
g_value_unset (&params[0]);
g_value_unset (&params[1]);
return result;
}
static void
fd_source_closure_marshal (GClosure *closure,
GValue *return_value,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint,
gpointer marshal_data)
{
GFDSourceFunc callback;
GCClosure *cc = (GCClosure*) closure;
gboolean v_return;
g_return_if_fail (return_value != NULL);
g_return_if_fail (n_param_values == 0);
callback = (GFDSourceFunc) (marshal_data ? marshal_data : cc->callback);
v_return = callback (g_value_get_int (param_values),
g_value_get_flags (param_values + 1),
closure->data);
g_value_set_boolean (return_value, v_return);
}
static GSourceFuncs fd_source_funcs = {
fd_source_prepare,
fd_source_check,
fd_source_dispatch,
fd_source_finalize,
(GSourceFunc)fd_source_closure_callback,
(GSourceDummyMarshal)fd_source_closure_marshal,
};
GSource *
_g_fd_source_new (int fd,
gushort events,
GCancellable *cancellable)
{
GSource *source;
FDSource *fd_source;
source = g_source_new (&fd_source_funcs, sizeof (FDSource));
fd_source = (FDSource *)source;
fd_source->pollfd.fd = fd;
fd_source->pollfd.events = events;
g_source_add_poll (source, &fd_source->pollfd);
if (cancellable)
{
GSource *cancellable_source = g_cancellable_source_new (cancellable);
g_source_set_dummy_callback (cancellable_source);
g_source_add_child_source (source, cancellable_source);
g_source_unref (cancellable_source);
}
return source;
}