luc14n0/glib
1
0
Fork 0
mirror of https://gitlab.gnome.org/GNOME/glib.git synced 2024-11-14 05:16:18 +01:00
Code Issues Packages Projects Releases Wiki Activity
c7996825ce
glib/gio/gsimpleasyncresult.c
Dan Winship 55e7ca6e1b gio: deprecate gioscheduler, soft deprecate GSimpleAsyncResult 
Reimplement gioscheduler in terms of GTask, and deprecate the original
gioscheduler methods. Update docs to point people to GTask rather than
gioscheduler and GSimpleAsyncResult, but don't actually formally
deprecate GSimpleAsyncResult yet.

https://bugzilla.gnome.org/show_bug.cgi?id=661767
2012-10-10 10:29:36 -04:00

1107 lines
35 KiB
C
Raw Blame History

/* 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 <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "gsimpleasyncresult.h"
#include "gasyncresult.h"
#include "gcancellable.h"
#include "gioscheduler.h"
#include <gio/gioerror.h>
#include "glibintl.h"
/**
* SECTION:gsimpleasyncresult
* @short_description: Simple asynchronous results implementation
* @include: gio/gio.h
* @see_also: #GAsyncResult
*
* <note><para>
* As of GLib 2.36, #GSimpleAsyncResult is deprecated in favor of
* #GTask, which provides a simpler API.
* </para></note>
*
* #GSimpleAsyncResult implements #GAsyncResult.
*
* GSimpleAsyncResult handles #GAsyncReadyCallback<!-- -->s, error
* reporting, operation cancellation and the final state of an operation,
* completely transparent to the application. Results can be returned
* as a pointer e.g. for functions that return data that is collected
* asynchronously, a boolean value for checking the success or failure
* of an operation, or a #gssize for operations which return the number
* of bytes modified by the operation; all of the simple return cases
* are covered.
*
* Most of the time, an application will not need to know of the details
* of this API; it is handled transparently, and any necessary operations
* are handled by #GAsyncResult's interface. However, if implementing a
* new GIO module, for writing language bindings, or for complex
* applications that need better control of how asynchronous operations
* are completed, it is important to understand this functionality.
*
* GSimpleAsyncResults are tagged with the calling function to ensure
* that asynchronous functions and their finishing functions are used
* together correctly.
*
* To create a new #GSimpleAsyncResult, call g_simple_async_result_new().
* If the result needs to be created for a #GError, use
* g_simple_async_result_new_from_error() or
* g_simple_async_result_new_take_error(). If a #GError is not available
* (e.g. the asynchronous operation's doesn't take a #GError argument),
* but the result still needs to be created for an error condition, use
* g_simple_async_result_new_error() (or g_simple_async_result_set_error_va()
* if your application or binding requires passing a variable argument list
* directly), and the error can then be propagated through the use of
* g_simple_async_result_propagate_error().
*
* An asynchronous operation can be made to ignore a cancellation event by
* calling g_simple_async_result_set_handle_cancellation() with a
* #GSimpleAsyncResult for the operation and %FALSE. This is useful for
* operations that are dangerous to cancel, such as close (which would
* cause a leak if cancelled before being run).
*
* GSimpleAsyncResult can integrate into GLib's event loop, #GMainLoop,
* or it can use #GThread<!-- -->s.
* g_simple_async_result_complete() will finish an I/O task directly
* from the point where it is called. g_simple_async_result_complete_in_idle()
* will finish it from an idle handler in the <link
* linkend="g-main-context-push-thread-default">thread-default main
* context</link>. g_simple_async_result_run_in_thread() will run the
* job in a separate thread and then deliver the result to the
* thread-default main context.
*
* To set the results of an asynchronous function,
* g_simple_async_result_set_op_res_gpointer(),
* g_simple_async_result_set_op_res_gboolean(), and
* g_simple_async_result_set_op_res_gssize()
* are provided, setting the operation's result to a gpointer, gboolean, or
* gssize, respectively.
*
* Likewise, to get the result of an asynchronous function,
* g_simple_async_result_get_op_res_gpointer(),
* g_simple_async_result_get_op_res_gboolean(), and
* g_simple_async_result_get_op_res_gssize() are
* provided, getting the operation's result as a gpointer, gboolean, and
* gssize, respectively.
*
* For the details of the requirements implementations must respect, see
* #GAsyncResult. A typical implementation of an asynchronous operation
* using GSimpleAsyncResult looks something like this:
*
* |[
* static void
* baked_cb (Cake *cake,
* gpointer user_data)
* {
* /&ast; In this example, this callback is not given a reference to the cake, so
* &ast; the GSimpleAsyncResult has to take a reference to it.
* &ast;/
* GSimpleAsyncResult *result = user_data;
*
* if (cake == NULL)
* g_simple_async_result_set_error (result,
* BAKER_ERRORS,
* BAKER_ERROR_NO_FLOUR,
* "Go to the supermarket");
* else
* g_simple_async_result_set_op_res_gpointer (result,
* g_object_ref (cake),
* g_object_unref);
*
*
* /&ast; In this example, we assume that baked_cb is called as a callback from
* &ast; the mainloop, so it's safe to complete the operation synchronously here.
* &ast; If, however, _baker_prepare_cake () might call its callback without
* &ast; first returning to the mainloop — inadvisable, but some APIs do so —
* &ast; we would need to use g_simple_async_result_complete_in_idle().
* &ast;/
* g_simple_async_result_complete (result);
* g_object_unref (result);
* }
*
* void
* baker_bake_cake_async (Baker *self,
* guint radius,
* GAsyncReadyCallback callback,
* gpointer user_data)
* {
* GSimpleAsyncResult *simple;
* Cake *cake;
*
* if (radius < 3)
* {
* g_simple_async_report_error_in_idle (G_OBJECT (self),
* callback,
* user_data,
* BAKER_ERRORS,
* BAKER_ERROR_TOO_SMALL,
* "%ucm radius cakes are silly",
* radius);
* return;
* }
*
* simple = g_simple_async_result_new (G_OBJECT (self),
* callback,
* user_data,
* baker_bake_cake_async);
* cake = _baker_get_cached_cake (self, radius);
*
* if (cake != NULL)
* {
* g_simple_async_result_set_op_res_gpointer (simple,
* g_object_ref (cake),
* g_object_unref);
* g_simple_async_result_complete_in_idle (simple);
* g_object_unref (simple);
* /&ast; Drop the reference returned by _baker_get_cached_cake(); the
* &ast; GSimpleAsyncResult has taken its own reference.
* &ast;/
* g_object_unref (cake);
* return;
* }
*
* _baker_prepare_cake (self, radius, baked_cb, simple);
* }
*
* Cake *
* baker_bake_cake_finish (Baker *self,
* GAsyncResult *result,
* GError **error)
* {
* GSimpleAsyncResult *simple;
* Cake *cake;
*
* g_return_val_if_fail (g_simple_async_result_is_valid (result,
* G_OBJECT (self),
* baker_bake_cake_async),
* NULL);
*
* simple = (GSimpleAsyncResult *) result;
*
* if (g_simple_async_result_propagate_error (simple, error))
* return NULL;
*
* cake = CAKE (g_simple_async_result_get_op_res_gpointer (simple));
* return g_object_ref (cake);
* }
* ]|
*/
static void g_simple_async_result_async_result_iface_init (GAsyncResultIface *iface);
struct _GSimpleAsyncResult
{
GObject parent_instance;
GObject *source_object;
GAsyncReadyCallback callback;
gpointer user_data;
GMainContext *context;
GError *error;
gboolean failed;
gboolean handle_cancellation;
GCancellable *check_cancellable;
gpointer source_tag;
union {
gpointer v_pointer;
gboolean v_boolean;
gssize v_ssize;
} op_res;
GDestroyNotify destroy_op_res;
};
struct _GSimpleAsyncResultClass
{
GObjectClass parent_class;
};
G_DEFINE_TYPE_WITH_CODE (GSimpleAsyncResult, g_simple_async_result, G_TYPE_OBJECT,
G_IMPLEMENT_INTERFACE (G_TYPE_ASYNC_RESULT,
g_simple_async_result_async_result_iface_init))
static void
clear_op_res (GSimpleAsyncResult *simple)
{
if (simple->destroy_op_res)
simple->destroy_op_res (simple->op_res.v_pointer);
simple->destroy_op_res = NULL;
simple->op_res.v_ssize = 0;
}
static void
g_simple_async_result_finalize (GObject *object)
{
GSimpleAsyncResult *simple;
simple = G_SIMPLE_ASYNC_RESULT (object);
if (simple->source_object)
g_object_unref (simple->source_object);
if (simple->check_cancellable)
g_object_unref (simple->check_cancellable);
g_main_context_unref (simple->context);
clear_op_res (simple);
if (simple->error)
g_error_free (simple->error);
G_OBJECT_CLASS (g_simple_async_result_parent_class)->finalize (object);
}
static void
g_simple_async_result_class_init (GSimpleAsyncResultClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->finalize = g_simple_async_result_finalize;
}
static void
g_simple_async_result_init (GSimpleAsyncResult *simple)
{
simple->handle_cancellation = TRUE;
simple->context = g_main_context_ref_thread_default ();
}
/**
* g_simple_async_result_new:
* @source_object: (allow-none): a #GObject, or %NULL.
* @callback: (scope async): a #GAsyncReadyCallback.
* @user_data: (closure): user data passed to @callback.
* @source_tag: the asynchronous function.
*
* Creates a #GSimpleAsyncResult.
*
* The common convention is to create the #GSimpleAsyncResult in the
* function that starts the asynchronous operation and use that same
* function as the @source_tag.
*
* If your operation supports cancellation with #GCancellable (which it
* probably should) then you should provide the user's cancellable to
* g_simple_async_result_set_check_cancellable() immediately after
* this function returns.
*
* Returns: a #GSimpleAsyncResult.
**/
GSimpleAsyncResult *
g_simple_async_result_new (GObject *source_object,
GAsyncReadyCallback callback,
gpointer user_data,
gpointer source_tag)
{
GSimpleAsyncResult *simple;
g_return_val_if_fail (!source_object || G_IS_OBJECT (source_object), NULL);
simple = g_object_new (G_TYPE_SIMPLE_ASYNC_RESULT, NULL);
simple->callback = callback;
if (source_object)
simple->source_object = g_object_ref (source_object);
else
simple->source_object = NULL;
simple->user_data = user_data;
simple->source_tag = source_tag;
return simple;
}
/**
* g_simple_async_result_new_from_error:
* @source_object: (allow-none): a #GObject, or %NULL.
* @callback: (scope async): a #GAsyncReadyCallback.
* @user_data: (closure): user data passed to @callback.
* @error: a #GError
*
* Creates a #GSimpleAsyncResult from an error condition.
*
* Returns: a #GSimpleAsyncResult.
**/
GSimpleAsyncResult *
g_simple_async_result_new_from_error (GObject *source_object,
GAsyncReadyCallback callback,
gpointer user_data,
const GError *error)
{
GSimpleAsyncResult *simple;
g_return_val_if_fail (!source_object || G_IS_OBJECT (source_object), NULL);
simple = g_simple_async_result_new (source_object,
callback,
user_data, NULL);
g_simple_async_result_set_from_error (simple, error);
return simple;
}
/**
* g_simple_async_result_new_take_error: (skip)
* @source_object: (allow-none): a #GObject, or %NULL
* @callback: (scope async): a #GAsyncReadyCallback
* @user_data: (closure): user data passed to @callback
* @error: a #GError
*
* Creates a #GSimpleAsyncResult from an error condition, and takes over the
* caller's ownership of @error, so the caller does not need to free it anymore.
*
* Returns: a #GSimpleAsyncResult
*
* Since: 2.28
**/
GSimpleAsyncResult *
g_simple_async_result_new_take_error (GObject *source_object,
GAsyncReadyCallback callback,
gpointer user_data,
GError *error)
{
GSimpleAsyncResult *simple;
g_return_val_if_fail (!source_object || G_IS_OBJECT (source_object), NULL);
simple = g_simple_async_result_new (source_object,
callback,
user_data, NULL);
g_simple_async_result_take_error (simple, error);
return simple;
}
/**
* g_simple_async_result_new_error:
* @source_object: (allow-none): a #GObject, or %NULL.
* @callback: (scope async): a #GAsyncReadyCallback.
* @user_data: (closure): user data passed to @callback.
* @domain: a #GQuark.
* @code: an error code.
* @format: a string with format characters.
* @...: a list of values to insert into @format.
*
* Creates a new #GSimpleAsyncResult with a set error.
*
* Returns: a #GSimpleAsyncResult.
**/
GSimpleAsyncResult *
g_simple_async_result_new_error (GObject *source_object,
GAsyncReadyCallback callback,
gpointer user_data,
GQuark domain,
gint code,
const char *format,
...)
{
GSimpleAsyncResult *simple;
va_list args;
g_return_val_if_fail (!source_object || G_IS_OBJECT (source_object), NULL);
g_return_val_if_fail (domain != 0, NULL);
g_return_val_if_fail (format != NULL, NULL);
simple = g_simple_async_result_new (source_object,
callback,
user_data, NULL);
va_start (args, format);
g_simple_async_result_set_error_va (simple, domain, code, format, args);
va_end (args);
return simple;
}
static gpointer
g_simple_async_result_get_user_data (GAsyncResult *res)
{
return G_SIMPLE_ASYNC_RESULT (res)->user_data;
}
static GObject *
g_simple_async_result_get_source_object (GAsyncResult *res)
{
if (G_SIMPLE_ASYNC_RESULT (res)->source_object)
return g_object_ref (G_SIMPLE_ASYNC_RESULT (res)->source_object);
return NULL;
}
static gboolean
g_simple_async_result_is_tagged (GAsyncResult *res,
gpointer source_tag)
{
return G_SIMPLE_ASYNC_RESULT (res)->source_tag == source_tag;
}
static void
g_simple_async_result_async_result_iface_init (GAsyncResultIface *iface)
{
iface->get_user_data = g_simple_async_result_get_user_data;
iface->get_source_object = g_simple_async_result_get_source_object;
iface->is_tagged = g_simple_async_result_is_tagged;
}
/**
* g_simple_async_result_set_handle_cancellation:
* @simple: a #GSimpleAsyncResult.
* @handle_cancellation: a #gboolean.
*
* Sets whether to handle cancellation within the asynchronous operation.
*
* This function has nothing to do with
* g_simple_async_result_set_check_cancellable(). It only refers to the
* #GCancellable passed to g_simple_async_result_run_in_thread().
**/
void
g_simple_async_result_set_handle_cancellation (GSimpleAsyncResult *simple,
gboolean handle_cancellation)
{
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
simple->handle_cancellation = handle_cancellation;
}
/**
* g_simple_async_result_get_source_tag: (skip)
* @simple: a #GSimpleAsyncResult.
*
* Gets the source tag for the #GSimpleAsyncResult.
*
* Returns: a #gpointer to the source object for the #GSimpleAsyncResult.
**/
gpointer
g_simple_async_result_get_source_tag (GSimpleAsyncResult *simple)
{
g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple), NULL);
return simple->source_tag;
}
/**
* g_simple_async_result_propagate_error:
* @simple: a #GSimpleAsyncResult.
* @dest: (out): a location to propagate the error to.
*
* Propagates an error from within the simple asynchronous result to
* a given destination.
*
* If the #GCancellable given to a prior call to
* g_simple_async_result_set_check_cancellable() is cancelled then this
* function will return %TRUE with @dest set appropriately.
*
* Returns: %TRUE if the error was propagated to @dest. %FALSE otherwise.
**/
gboolean
g_simple_async_result_propagate_error (GSimpleAsyncResult *simple,
GError **dest)
{
g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple), FALSE);
if (g_cancellable_set_error_if_cancelled (simple->check_cancellable, dest))
return TRUE;
if (simple->failed)
{
g_propagate_error (dest, simple->error);
simple->error = NULL;
return TRUE;
}
return FALSE;
}
/**
* g_simple_async_result_set_op_res_gpointer: (skip)
* @simple: a #GSimpleAsyncResult.
* @op_res: a pointer result from an asynchronous function.
* @destroy_op_res: a #GDestroyNotify function.
*
* Sets the operation result within the asynchronous result to a pointer.
**/
void
g_simple_async_result_set_op_res_gpointer (GSimpleAsyncResult *simple,
gpointer op_res,
GDestroyNotify destroy_op_res)
{
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
clear_op_res (simple);
simple->op_res.v_pointer = op_res;
simple->destroy_op_res = destroy_op_res;
}
/**
* g_simple_async_result_get_op_res_gpointer: (skip)
* @simple: a #GSimpleAsyncResult.
*
* Gets a pointer result as returned by the asynchronous function.
*
* Returns: a pointer from the result.
**/
gpointer
g_simple_async_result_get_op_res_gpointer (GSimpleAsyncResult *simple)
{
g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple), NULL);
return simple->op_res.v_pointer;
}
/**
* g_simple_async_result_set_op_res_gssize:
* @simple: a #GSimpleAsyncResult.
* @op_res: a #gssize.
*
* Sets the operation result within the asynchronous result to
* the given @op_res.
**/
void
g_simple_async_result_set_op_res_gssize (GSimpleAsyncResult *simple,
gssize op_res)
{
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
clear_op_res (simple);
simple->op_res.v_ssize = op_res;
}
/**
* g_simple_async_result_get_op_res_gssize:
* @simple: a #GSimpleAsyncResult.
*
* Gets a gssize from the asynchronous result.
*
* Returns: a gssize returned from the asynchronous function.
**/
gssize
g_simple_async_result_get_op_res_gssize (GSimpleAsyncResult *simple)
{
g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple), 0);
return simple->op_res.v_ssize;
}
/**
* g_simple_async_result_set_op_res_gboolean:
* @simple: a #GSimpleAsyncResult.
* @op_res: a #gboolean.
*
* Sets the operation result to a boolean within the asynchronous result.
**/
void
g_simple_async_result_set_op_res_gboolean (GSimpleAsyncResult *simple,
gboolean op_res)
{
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
clear_op_res (simple);
simple->op_res.v_boolean = !!op_res;
}
/**
* g_simple_async_result_get_op_res_gboolean:
* @simple: a #GSimpleAsyncResult.
*
* Gets the operation result boolean from within the asynchronous result.
*
* Returns: %TRUE if the operation's result was %TRUE, %FALSE
* if the operation's result was %FALSE.
**/
gboolean
g_simple_async_result_get_op_res_gboolean (GSimpleAsyncResult *simple)
{
g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple), FALSE);
return simple->op_res.v_boolean;
}
/**
* g_simple_async_result_set_from_error:
* @simple: a #GSimpleAsyncResult.
* @error: #GError.
*
* Sets the result from a #GError.
**/
void
g_simple_async_result_set_from_error (GSimpleAsyncResult *simple,
const GError *error)
{
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
g_return_if_fail (error != NULL);
if (simple->error)
g_error_free (simple->error);
simple->error = g_error_copy (error);
simple->failed = TRUE;
}
/**
* g_simple_async_result_take_error: (skip)
* @simple: a #GSimpleAsyncResult
* @error: a #GError
*
* Sets the result from @error, and takes over the caller's ownership
* of @error, so the caller does not need to free it any more.
*
* Since: 2.28
**/
void
g_simple_async_result_take_error (GSimpleAsyncResult *simple,
GError *error)
{
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
g_return_if_fail (error != NULL);
if (simple->error)
g_error_free (simple->error);
simple->error = error;
simple->failed = TRUE;
}
/**
* g_simple_async_result_set_error_va: (skip)
* @simple: a #GSimpleAsyncResult.
* @domain: a #GQuark (usually #G_IO_ERROR).
* @code: an error code.
* @format: a formatted error reporting string.
* @args: va_list of arguments.
*
* Sets an error within the asynchronous result without a #GError.
* Unless writing a binding, see g_simple_async_result_set_error().
**/
void
g_simple_async_result_set_error_va (GSimpleAsyncResult *simple,
GQuark domain,
gint code,
const char *format,
va_list args)
{
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
g_return_if_fail (domain != 0);
g_return_if_fail (format != NULL);
if (simple->error)
g_error_free (simple->error);
simple->error = g_error_new_valist (domain, code, format, args);
simple->failed = TRUE;
}
/**
* g_simple_async_result_set_error: (skip)
* @simple: a #GSimpleAsyncResult.
* @domain: a #GQuark (usually #G_IO_ERROR).
* @code: an error code.
* @format: a formatted error reporting string.
* @...: a list of variables to fill in @format.
*
* Sets an error within the asynchronous result without a #GError.
**/
void
g_simple_async_result_set_error (GSimpleAsyncResult *simple,
GQuark domain,
gint code,
const char *format,
...)
{
va_list args;
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
g_return_if_fail (domain != 0);
g_return_if_fail (format != NULL);
va_start (args, format);
g_simple_async_result_set_error_va (simple, domain, code, format, args);
va_end (args);
}
/**
* g_simple_async_result_complete:
* @simple: a #GSimpleAsyncResult.
*
* Completes an asynchronous I/O job immediately. Must be called in
* the thread where the asynchronous result was to be delivered, as it
* invokes the callback directly. If you are in a different thread use
* g_simple_async_result_complete_in_idle().
*
* Calling this function takes a reference to @simple for as long as
* is needed to complete the call.
**/
void
g_simple_async_result_complete (GSimpleAsyncResult *simple)
{
#ifndef G_DISABLE_CHECKS
GSource *current_source;
GMainContext *current_context;
#endif
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
#ifndef G_DISABLE_CHECKS
current_source = g_main_current_source ();
if (current_source && !g_source_is_destroyed (current_source))
{
current_context = g_source_get_context (current_source);
if (simple->context != current_context)
g_warning ("g_simple_async_result_complete() called from wrong context!");
}
#endif
if (simple->callback)
{
g_main_context_push_thread_default (simple->context);
simple->callback (simple->source_object,
G_ASYNC_RESULT (simple),
simple->user_data);
g_main_context_pop_thread_default (simple->context);
}
}
static gboolean
complete_in_idle_cb (gpointer data)
{
GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (data);
g_simple_async_result_complete (simple);
return FALSE;
}
/**
* g_simple_async_result_complete_in_idle:
* @simple: a #GSimpleAsyncResult.
*
* Completes an asynchronous function in an idle handler in the <link
* linkend="g-main-context-push-thread-default">thread-default main
* loop</link> of the thread that @simple was initially created in
* (and re-pushes that context around the invocation of the callback).
*
* Calling this function takes a reference to @simple for as long as
* is needed to complete the call.
*/
void
g_simple_async_result_complete_in_idle (GSimpleAsyncResult *simple)
{
GSource *source;
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
g_object_ref (simple);
source = g_idle_source_new ();
g_source_set_priority (source, G_PRIORITY_DEFAULT);
g_source_set_callback (source, complete_in_idle_cb, simple, g_object_unref);
g_source_attach (source, simple->context);
g_source_unref (source);
}
typedef struct {
GSimpleAsyncResult *simple;
GCancellable *cancellable;
GSimpleAsyncThreadFunc func;
} RunInThreadData;
static gboolean
complete_in_idle_cb_for_thread (gpointer _data)
{
RunInThreadData *data = _data;
GSimpleAsyncResult *simple;
simple = data->simple;
if (simple->handle_cancellation &&
g_cancellable_is_cancelled (data->cancellable))
g_simple_async_result_set_error (simple,
G_IO_ERROR,
G_IO_ERROR_CANCELLED,
"%s", _("Operation was cancelled"));
g_simple_async_result_complete (simple);
if (data->cancellable)
g_object_unref (data->cancellable);
g_object_unref (data->simple);
g_free (data);
return FALSE;
}
static gboolean
run_in_thread (GIOSchedulerJob *job,
GCancellable *c,
gpointer _data)
{
RunInThreadData *data = _data;
GSimpleAsyncResult *simple = data->simple;
GSource *source;
if (simple->handle_cancellation &&
g_cancellable_is_cancelled (c))
g_simple_async_result_set_error (simple,
G_IO_ERROR,
G_IO_ERROR_CANCELLED,
"%s", _("Operation was cancelled"));
else
data->func (simple,
simple->source_object,
c);
source = g_idle_source_new ();
g_source_set_priority (source, G_PRIORITY_DEFAULT);
g_source_set_callback (source, complete_in_idle_cb_for_thread, data, NULL);
g_source_attach (source, simple->context);
g_source_unref (source);
return FALSE;
}
/**
* g_simple_async_result_run_in_thread: (skip)
* @simple: a #GSimpleAsyncResult.
* @func: a #GSimpleAsyncThreadFunc.
* @io_priority: the io priority of the request.
* @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
*
* Runs the asynchronous job in a separate thread and then calls
* g_simple_async_result_complete_in_idle() on @simple to return
* the result to the appropriate main loop.
*
* Calling this function takes a reference to @simple for as long as
* is needed to run the job and report its completion.
*/
void
g_simple_async_result_run_in_thread (GSimpleAsyncResult *simple,
GSimpleAsyncThreadFunc func,
int io_priority,
GCancellable *cancellable)
{
RunInThreadData *data;
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
g_return_if_fail (func != NULL);
data = g_new (RunInThreadData, 1);
data->func = func;
data->simple = g_object_ref (simple);
data->cancellable = cancellable;
if (cancellable)
g_object_ref (cancellable);
G_GNUC_BEGIN_IGNORE_DEPRECATIONS;
g_io_scheduler_push_job (run_in_thread, data, NULL, io_priority, cancellable);
G_GNUC_END_IGNORE_DEPRECATIONS;
}
/**
* g_simple_async_result_is_valid:
* @result: the #GAsyncResult passed to the _finish function.
* @source: the #GObject passed to the _finish function.
* @source_tag: the asynchronous function.
*
* Ensures that the data passed to the _finish function of an async
* operation is consistent. Three checks are performed.
*
* First, @result is checked to ensure that it is really a
* #GSimpleAsyncResult. Second, @source is checked to ensure that it
* matches the source object of @result. Third, @source_tag is
* checked to ensure that it is either %NULL (as it is when the result was
* created by g_simple_async_report_error_in_idle() or
* g_simple_async_report_gerror_in_idle()) or equal to the
* @source_tag argument given to g_simple_async_result_new() (which, by
* convention, is a pointer to the _async function corresponding to the
* _finish function from which this function is called).
*
* Returns: #TRUE if all checks passed or #FALSE if any failed.
*
* Since: 2.20
**/
gboolean
g_simple_async_result_is_valid (GAsyncResult *result,
GObject *source,
gpointer source_tag)
{
GSimpleAsyncResult *simple;
GObject *cmp_source;
if (!G_IS_SIMPLE_ASYNC_RESULT (result))
return FALSE;
simple = (GSimpleAsyncResult *)result;
cmp_source = g_async_result_get_source_object (result);
if (cmp_source != source)
{
if (cmp_source != NULL)
g_object_unref (cmp_source);
return FALSE;
}
if (cmp_source != NULL)
g_object_unref (cmp_source);
return source_tag == NULL ||
source_tag == g_simple_async_result_get_source_tag (simple);
}
/**
* g_simple_async_report_error_in_idle: (skip)
* @object: (allow-none): a #GObject, or %NULL.
* @callback: a #GAsyncReadyCallback.
* @user_data: user data passed to @callback.
* @domain: a #GQuark containing the error domain (usually #G_IO_ERROR).
* @code: a specific error code.
* @format: a formatted error reporting string.
* @...: a list of variables to fill in @format.
*
* Reports an error in an asynchronous function in an idle function by
* directly setting the contents of the #GAsyncResult with the given error
* information.
**/
void
g_simple_async_report_error_in_idle (GObject *object,
GAsyncReadyCallback callback,
gpointer user_data,
GQuark domain,
gint code,
const char *format,
...)
{
GSimpleAsyncResult *simple;
va_list args;
g_return_if_fail (!object || G_IS_OBJECT (object));
g_return_if_fail (domain != 0);
g_return_if_fail (format != NULL);
simple = g_simple_async_result_new (object,
callback,
user_data, NULL);
va_start (args, format);
g_simple_async_result_set_error_va (simple, domain, code, format, args);
va_end (args);
g_simple_async_result_complete_in_idle (simple);
g_object_unref (simple);
}
/**
* g_simple_async_report_gerror_in_idle:
* @object: (allow-none): a #GObject, or %NULL
* @callback: (scope async): a #GAsyncReadyCallback.
* @user_data: (closure): user data passed to @callback.
* @error: the #GError to report
*
* Reports an error in an idle function. Similar to
* g_simple_async_report_error_in_idle(), but takes a #GError rather
* than building a new one.
**/
void
g_simple_async_report_gerror_in_idle (GObject *object,
GAsyncReadyCallback callback,
gpointer user_data,
const GError *error)
{
GSimpleAsyncResult *simple;
g_return_if_fail (!object || G_IS_OBJECT (object));
g_return_if_fail (error != NULL);
simple = g_simple_async_result_new_from_error (object,
callback,
user_data,
error);
g_simple_async_result_complete_in_idle (simple);
g_object_unref (simple);
}
/**
* g_simple_async_report_take_gerror_in_idle: (skip)
* @object: (allow-none): a #GObject, or %NULL
* @callback: a #GAsyncReadyCallback.
* @user_data: user data passed to @callback.
* @error: the #GError to report
*
* Reports an error in an idle function. Similar to
* g_simple_async_report_gerror_in_idle(), but takes over the caller's
* ownership of @error, so the caller does not have to free it any more.
*
* Since: 2.28
**/
void
g_simple_async_report_take_gerror_in_idle (GObject *object,
GAsyncReadyCallback callback,
gpointer user_data,
GError *error)
{
GSimpleAsyncResult *simple;
g_return_if_fail (!object || G_IS_OBJECT (object));
g_return_if_fail (error != NULL);
simple = g_simple_async_result_new_take_error (object,
callback,
user_data,
error);
g_simple_async_result_complete_in_idle (simple);
g_object_unref (simple);
}
/**
* g_simple_async_result_set_check_cancellable:
* @simple: a #GSimpleAsyncResult
* @check_cancellable: (allow-none): a #GCancellable to check, or %NULL to unset
*
* Sets a #GCancellable to check before dispatching results.
*
* This function has one very specific purpose: the provided cancellable
* is checked at the time of g_simple_async_result_propagate_error() If
* it is cancelled, these functions will return an "Operation was
* cancelled" error (%G_IO_ERROR_CANCELLED).
*
* Implementors of cancellable asynchronous functions should use this in
* order to provide a guarantee to their callers that cancelling an
* async operation will reliably result in an error being returned for
* that operation (even if a positive result for the operation has
* already been sent as an idle to the main context to be dispatched).
*
* The checking described above is done regardless of any call to the
* unrelated g_simple_async_result_set_handle_cancellation() function.
*
* Since: 2.32
**/
void
g_simple_async_result_set_check_cancellable (GSimpleAsyncResult *simple,
GCancellable *check_cancellable)
{
g_return_if_fail (G_IS_SIMPLE_ASYNC_RESULT (simple));
g_return_if_fail (check_cancellable == NULL || G_IS_CANCELLABLE (check_cancellable));
g_clear_object (&simple->check_cancellable);
if (check_cancellable)
simple->check_cancellable = g_object_ref (check_cancellable);
}
Reference in New Issue View Git Blame Copy Permalink