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https://gitlab.gnome.org/GNOME/glib.git
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e26a8a5981
It fixes a race. g_source_attach() had the following check to ensure a
loop blocked on poll() would wakeup.
if (do_wakeup && context->owner && context->owner != G_THREAD_SELF)
g_wakeup_signal (context->wakeup);
However it doesn't contemplate an implementation where poll()ing is a
non-blocking operation that will be scheduled while the thread is
released to perform other tasks. This scenario opens up several
different possibilities where the condition would fail to hold true. I
experienced two of such races.
The first race pertains to a mono-threaded application. Do keep in mind
that integrating GLib to a foreign event loop will make GLib act as a
slave in the new event loop. When you post a new work unit to execute in
the thread managed by the foreign event loop, you don't use
g_main_context_invoke(). In fact the only reason to integrate
GMainContext in a foreign event loop is to make the two of them
communicate. So from time to time, the foreign event loop will execute
callbacks that manipulate the GMainContext loop. An illustration
follows.
// in this callback we translate an event from the foreign event loop
// to an event in the GMainContext event loop (that runs in the same
// thread)
static void my_event_loop_callback(void* data)
{
GMainContext* ctx = /* ... */;
// ...
g_source_attach(source, ctx);
}
int main()
{
// ...
my_event_loop_invoke(my_event_loop_callback, data);
// ...
// this function has all mechanisms in place to run the foreign
// event loop and the hooks to call
// g_main_context_{prepare,query,check,dispatch}
my_event_loop_run();
}
In this case, you would have the following series of calls:
1. g_main_context_prepare()
2. g_main_context_query()
3. A callback to my_event_loop is registered when any fd on the set is
ready or the timeout is reached.
4. The thread is released to perform other tasks.
5. One of the tasks executed wishes to communicate with my_event_loop
and enters my_event_loop_callback.
6. g_source_attach() is called.
7. g_source_attach() detects do_wakeup=TRUE, context->owner != NULL, and
context->owner == G_THREAD_SELF so g_wakeup_signal() is skipped.
8. None of the fds on the GLib poll() set becomes ready nor the GLib
timeout expires. The my_event_loop callback that would call
g_main_context_check() is never executed. Deadlock.
A shallow analysis will fail to detect the race here. The explanation
seems to showcase a scenario that will deterministically fail with a
deadlock every time. However do keep in mind that my_event_loop_callback
could be invoked before or after g_main_context_prepare(). There is an
_event_ race here. Furthermore, some GLib libraries such as GDBus will
initialize objects from extra threads (GAsyncInitable interface) and
invoke the result on the original thread when ready (g_source_attach()
will eventually be called). Now you have scenarios closer to standard
race examples.
The other scenario where a race would manifest happens in a
multi-threaded application that has a concurrency design similar to the
actor model. No actor executes in two threads simultaneously, but it's
not guaranteed that it'll always wake-up in the same thread. It'd
perform steps 1-4 just as in the previous example, but before thread
control is returned to the pool, it'd call g_main_context_release(). Now
g_source_attach() would skip g_wakeup_signal() for a different reason:
7. g_source_attach() detects do_wakeup=TRUE, context->owner == NULL so
g_wakeup_signal() is skipped.
8. Same as before.
Certainly there are other concurrency designs where this optimization
would cause a deadlock, but all of them have origin in the same place:
the optimization assumes the poll() implementation is a blocking
operation and the thread will never be released to perform other tasks
(possibly involving GLib calls) while result is not ready. They share
not only the same problem, but also the same solution: do not make
assumptions and just call g_wakeup_signal().
This patch implements this solution by introducing the
G_MAIN_CONTEXT_FLAGS_OWNERLESS_POLLING flag. This flag will force a call
to g_wakeup_signal() and fix the race on foreign event loops. The reason
to prevent changing this option after creation is to avoid other races
that would lead to event loss. Construction is the only proper time to
set this option.
The implementation design means we do not change **any** semantics for
current working code. If you don't set the new flag, the code won't
enter in different branches and current behavior won't be affected. The
patch is small and easy to follow too.
836 lines
29 KiB
C
836 lines
29 KiB
C
/* gmain.h - the GLib Main loop
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* Copyright (C) 1998-2000 Red Hat, Inc.
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*
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* This library is free software; you can redistribute it and/or
|
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* modify it under the terms of the GNU Lesser General Public
|
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
* Lesser General Public License for more details.
|
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*
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* You should have received a copy of the GNU Lesser General Public License
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* along with this library; if not, see <http://www.gnu.org/licenses/>.
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*/
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#ifndef __G_MAIN_H__
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#define __G_MAIN_H__
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#if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
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#error "Only <glib.h> can be included directly."
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#endif
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#include <glib/gpoll.h>
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#include <glib/gslist.h>
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#include <glib/gthread.h>
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G_BEGIN_DECLS
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typedef enum /*< flags >*/
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{
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G_IO_IN GLIB_SYSDEF_POLLIN,
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G_IO_OUT GLIB_SYSDEF_POLLOUT,
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G_IO_PRI GLIB_SYSDEF_POLLPRI,
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G_IO_ERR GLIB_SYSDEF_POLLERR,
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G_IO_HUP GLIB_SYSDEF_POLLHUP,
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G_IO_NVAL GLIB_SYSDEF_POLLNVAL
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} GIOCondition;
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/**
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* GMainContextFlags:
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* @G_MAIN_CONTEXT_FLAGS_NONE: Default behaviour.
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* @G_MAIN_CONTEXT_FLAGS_OWNERLESS_POLLING: Assume that polling for events will
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* free the thread to process other jobs. That's useful if you're using
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* `g_main_context_{prepare,query,check,dispatch}` to integrate GMainContext in
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* other event loops.
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*
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* Flags to pass to g_main_context_new_with_flags() which affect the behaviour
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* of a #GMainContext.
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*
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* Since: 2.72
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*/
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GLIB_AVAILABLE_TYPE_IN_2_72
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typedef enum /*< flags >*/
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{
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G_MAIN_CONTEXT_FLAGS_NONE = 0,
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G_MAIN_CONTEXT_FLAGS_OWNERLESS_POLLING = 1
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} GMainContextFlags;
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/**
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* GMainContext:
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*
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* The `GMainContext` struct is an opaque data
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* type representing a set of sources to be handled in a main loop.
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*/
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typedef struct _GMainContext GMainContext;
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/**
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* GMainLoop:
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*
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* The `GMainLoop` struct is an opaque data type
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* representing the main event loop of a GLib or GTK+ application.
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*/
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typedef struct _GMainLoop GMainLoop;
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/**
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* GSource:
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*
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* The `GSource` struct is an opaque data type
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* representing an event source.
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*/
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typedef struct _GSource GSource;
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typedef struct _GSourcePrivate GSourcePrivate;
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/**
|
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* GSourceCallbackFuncs:
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* @ref: Called when a reference is added to the callback object
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* @unref: Called when a reference to the callback object is dropped
|
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* @get: Called to extract the callback function and data from the
|
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* callback object.
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*
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* The `GSourceCallbackFuncs` struct contains
|
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* functions for managing callback objects.
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*/
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typedef struct _GSourceCallbackFuncs GSourceCallbackFuncs;
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|
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/**
|
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* GSourceFuncs:
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* @prepare: Called before all the file descriptors are polled. If the
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* source can determine that it is ready here (without waiting for the
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* results of the poll() call) it should return %TRUE. It can also return
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* a @timeout_ value which should be the maximum timeout (in milliseconds)
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* which should be passed to the poll() call. The actual timeout used will
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* be -1 if all sources returned -1, or it will be the minimum of all
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* the @timeout_ values returned which were >= 0. Since 2.36 this may
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* be %NULL, in which case the effect is as if the function always returns
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* %FALSE with a timeout of -1. If @prepare returns a
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* timeout and the source also has a ready time set, then the
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* lower of the two will be used.
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* @check: Called after all the file descriptors are polled. The source
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* should return %TRUE if it is ready to be dispatched. Note that some
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* time may have passed since the previous prepare function was called,
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* so the source should be checked again here. Since 2.36 this may
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* be %NULL, in which case the effect is as if the function always returns
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* %FALSE.
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* @dispatch: Called to dispatch the event source, after it has returned
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* %TRUE in either its @prepare or its @check function, or if a ready time
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* has been reached. The @dispatch function receives a callback function and
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* user data. The callback function may be %NULL if the source was never
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* connected to a callback using g_source_set_callback(). The @dispatch
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* function should call the callback function with @user_data and whatever
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* additional parameters are needed for this type of event source. The
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* return value of the @dispatch function should be #G_SOURCE_REMOVE if the
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* source should be removed or #G_SOURCE_CONTINUE to keep it.
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* @finalize: Called when the source is finalized. At this point, the source
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* will have been destroyed, had its callback cleared, and have been removed
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* from its #GMainContext, but it will still have its final reference count,
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* so methods can be called on it from within this function.
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*
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* The `GSourceFuncs` struct contains a table of
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* functions used to handle event sources in a generic manner.
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*
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* For idle sources, the prepare and check functions always return %TRUE
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* to indicate that the source is always ready to be processed. The prepare
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* function also returns a timeout value of 0 to ensure that the poll() call
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* doesn't block (since that would be time wasted which could have been spent
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* running the idle function).
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*
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* For timeout sources, the prepare and check functions both return %TRUE
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* if the timeout interval has expired. The prepare function also returns
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* a timeout value to ensure that the poll() call doesn't block too long
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* and miss the next timeout.
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*
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* For file descriptor sources, the prepare function typically returns %FALSE,
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* since it must wait until poll() has been called before it knows whether
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* any events need to be processed. It sets the returned timeout to -1 to
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* indicate that it doesn't mind how long the poll() call blocks. In the
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* check function, it tests the results of the poll() call to see if the
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* required condition has been met, and returns %TRUE if so.
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*/
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typedef struct _GSourceFuncs GSourceFuncs;
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/**
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* GPid:
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*
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* A type which is used to hold a process identification.
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*
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* On UNIX, processes are identified by a process id (an integer),
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* while Windows uses process handles (which are pointers).
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*
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* GPid is used in GLib only for descendant processes spawned with
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* the g_spawn functions.
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*/
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/* defined in glibconfig.h */
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/**
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* G_PID_FORMAT:
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*
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* A format specifier that can be used in printf()-style format strings
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* when printing a #GPid.
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*
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* Since: 2.50
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*/
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/* defined in glibconfig.h */
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/**
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* GSourceFunc:
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* @user_data: data passed to the function, set when the source was
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* created with one of the above functions
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*
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* Specifies the type of function passed to g_timeout_add(),
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* g_timeout_add_full(), g_idle_add(), and g_idle_add_full().
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*
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* When calling g_source_set_callback(), you may need to cast a function of a
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* different type to this type. Use G_SOURCE_FUNC() to avoid warnings about
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* incompatible function types.
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*
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* Returns: %FALSE if the source should be removed. #G_SOURCE_CONTINUE and
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* #G_SOURCE_REMOVE are more memorable names for the return value.
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*/
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typedef gboolean (*GSourceFunc) (gpointer user_data);
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/**
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* G_SOURCE_FUNC:
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* @f: a function pointer.
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*
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* Cast a function pointer to a #GSourceFunc, suppressing warnings from GCC 8
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* onwards with `-Wextra` or `-Wcast-function-type` enabled about the function
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* types being incompatible.
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||
*
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* For example, the correct type of callback for a source created by
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* g_child_watch_source_new() is #GChildWatchFunc, which accepts more arguments
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* than #GSourceFunc. Casting the function with `(GSourceFunc)` to call
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* g_source_set_callback() will trigger a warning, even though it will be cast
|
||
* back to the correct type before it is called by the source.
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*
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* Since: 2.58
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*/
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#define G_SOURCE_FUNC(f) ((GSourceFunc) (void (*)(void)) (f)) GLIB_AVAILABLE_MACRO_IN_2_58
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||
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/**
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* GChildWatchFunc:
|
||
* @pid: the process id of the child process
|
||
* @wait_status: Status information about the child process, encoded
|
||
* in a platform-specific manner
|
||
* @user_data: user data passed to g_child_watch_add()
|
||
*
|
||
* Prototype of a #GChildWatchSource callback, called when a child
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||
* process has exited.
|
||
*
|
||
* To interpret @wait_status, see the documentation
|
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* for g_spawn_check_wait_status(). In particular,
|
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* on Unix platforms, note that it is usually not equal
|
||
* to the integer passed to `exit()` or returned from `main()`.
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||
*/
|
||
typedef void (*GChildWatchFunc) (GPid pid,
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gint wait_status,
|
||
gpointer user_data);
|
||
|
||
|
||
/**
|
||
* GSourceDisposeFunc:
|
||
* @source: #GSource that is currently being disposed
|
||
*
|
||
* Dispose function for @source. See g_source_set_dispose_function() for
|
||
* details.
|
||
*
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||
* Since: 2.64
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||
*/
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||
GLIB_AVAILABLE_TYPE_IN_2_64
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typedef void (*GSourceDisposeFunc) (GSource *source);
|
||
|
||
struct _GSource
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||
{
|
||
/*< private >*/
|
||
gpointer callback_data;
|
||
GSourceCallbackFuncs *callback_funcs;
|
||
|
||
const GSourceFuncs *source_funcs;
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||
guint ref_count;
|
||
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||
GMainContext *context;
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||
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||
gint priority;
|
||
guint flags;
|
||
guint source_id;
|
||
|
||
GSList *poll_fds;
|
||
|
||
GSource *prev;
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||
GSource *next;
|
||
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||
char *name;
|
||
|
||
GSourcePrivate *priv;
|
||
};
|
||
|
||
struct _GSourceCallbackFuncs
|
||
{
|
||
void (*ref) (gpointer cb_data);
|
||
void (*unref) (gpointer cb_data);
|
||
void (*get) (gpointer cb_data,
|
||
GSource *source,
|
||
GSourceFunc *func,
|
||
gpointer *data);
|
||
};
|
||
|
||
/**
|
||
* GSourceDummyMarshal:
|
||
*
|
||
* This is just a placeholder for #GClosureMarshal,
|
||
* which cannot be used here for dependency reasons.
|
||
*/
|
||
typedef void (*GSourceDummyMarshal) (void);
|
||
|
||
struct _GSourceFuncs
|
||
{
|
||
gboolean (*prepare) (GSource *source,
|
||
gint *timeout_);/* Can be NULL */
|
||
gboolean (*check) (GSource *source);/* Can be NULL */
|
||
gboolean (*dispatch) (GSource *source,
|
||
GSourceFunc callback,
|
||
gpointer user_data);
|
||
void (*finalize) (GSource *source); /* Can be NULL */
|
||
|
||
/*< private >*/
|
||
/* For use by g_source_set_closure */
|
||
GSourceFunc closure_callback;
|
||
GSourceDummyMarshal closure_marshal; /* Really is of type GClosureMarshal */
|
||
};
|
||
|
||
/* Standard priorities */
|
||
|
||
/**
|
||
* G_PRIORITY_HIGH:
|
||
*
|
||
* Use this for high priority event sources.
|
||
*
|
||
* It is not used within GLib or GTK+.
|
||
*/
|
||
#define G_PRIORITY_HIGH -100
|
||
|
||
/**
|
||
* G_PRIORITY_DEFAULT:
|
||
*
|
||
* Use this for default priority event sources.
|
||
*
|
||
* In GLib this priority is used when adding timeout functions
|
||
* with g_timeout_add(). In GDK this priority is used for events
|
||
* from the X server.
|
||
*/
|
||
#define G_PRIORITY_DEFAULT 0
|
||
|
||
/**
|
||
* G_PRIORITY_HIGH_IDLE:
|
||
*
|
||
* Use this for high priority idle functions.
|
||
*
|
||
* GTK+ uses #G_PRIORITY_HIGH_IDLE + 10 for resizing operations,
|
||
* and #G_PRIORITY_HIGH_IDLE + 20 for redrawing operations. (This is
|
||
* done to ensure that any pending resizes are processed before any
|
||
* pending redraws, so that widgets are not redrawn twice unnecessarily.)
|
||
*/
|
||
#define G_PRIORITY_HIGH_IDLE 100
|
||
|
||
/**
|
||
* G_PRIORITY_DEFAULT_IDLE:
|
||
*
|
||
* Use this for default priority idle functions.
|
||
*
|
||
* In GLib this priority is used when adding idle functions with
|
||
* g_idle_add().
|
||
*/
|
||
#define G_PRIORITY_DEFAULT_IDLE 200
|
||
|
||
/**
|
||
* G_PRIORITY_LOW:
|
||
*
|
||
* Use this for very low priority background tasks.
|
||
*
|
||
* It is not used within GLib or GTK+.
|
||
*/
|
||
#define G_PRIORITY_LOW 300
|
||
|
||
/**
|
||
* G_SOURCE_REMOVE:
|
||
*
|
||
* Use this macro as the return value of a #GSourceFunc to remove
|
||
* the #GSource from the main loop.
|
||
*
|
||
* Since: 2.32
|
||
*/
|
||
#define G_SOURCE_REMOVE FALSE
|
||
|
||
/**
|
||
* G_SOURCE_CONTINUE:
|
||
*
|
||
* Use this macro as the return value of a #GSourceFunc to leave
|
||
* the #GSource in the main loop.
|
||
*
|
||
* Since: 2.32
|
||
*/
|
||
#define G_SOURCE_CONTINUE TRUE
|
||
|
||
/* GMainContext: */
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainContext *g_main_context_new (void);
|
||
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
|
||
GLIB_AVAILABLE_IN_2_72
|
||
GMainContext *g_main_context_new_with_flags (GMainContextFlags flags);
|
||
G_GNUC_END_IGNORE_DEPRECATIONS
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainContext *g_main_context_ref (GMainContext *context);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_unref (GMainContext *context);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainContext *g_main_context_default (void);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_main_context_iteration (GMainContext *context,
|
||
gboolean may_block);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_main_context_pending (GMainContext *context);
|
||
|
||
/* For implementation of legacy interfaces
|
||
*/
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_main_context_find_source_by_id (GMainContext *context,
|
||
guint source_id);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_main_context_find_source_by_user_data (GMainContext *context,
|
||
gpointer user_data);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_main_context_find_source_by_funcs_user_data (GMainContext *context,
|
||
GSourceFuncs *funcs,
|
||
gpointer user_data);
|
||
|
||
/* Low level functions for implementing custom main loops.
|
||
*/
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_wakeup (GMainContext *context);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_main_context_acquire (GMainContext *context);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_release (GMainContext *context);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_main_context_is_owner (GMainContext *context);
|
||
GLIB_DEPRECATED_IN_2_58_FOR(g_main_context_is_owner)
|
||
gboolean g_main_context_wait (GMainContext *context,
|
||
GCond *cond,
|
||
GMutex *mutex);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_main_context_prepare (GMainContext *context,
|
||
gint *priority);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gint g_main_context_query (GMainContext *context,
|
||
gint max_priority,
|
||
gint *timeout_,
|
||
GPollFD *fds,
|
||
gint n_fds);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_main_context_check (GMainContext *context,
|
||
gint max_priority,
|
||
GPollFD *fds,
|
||
gint n_fds);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_dispatch (GMainContext *context);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_set_poll_func (GMainContext *context,
|
||
GPollFunc func);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GPollFunc g_main_context_get_poll_func (GMainContext *context);
|
||
|
||
/* Low level functions for use by source implementations
|
||
*/
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_add_poll (GMainContext *context,
|
||
GPollFD *fd,
|
||
gint priority);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_remove_poll (GMainContext *context,
|
||
GPollFD *fd);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gint g_main_depth (void);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_main_current_source (void);
|
||
|
||
/* GMainContexts for other threads
|
||
*/
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_push_thread_default (GMainContext *context);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_pop_thread_default (GMainContext *context);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainContext *g_main_context_get_thread_default (void);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainContext *g_main_context_ref_thread_default (void);
|
||
|
||
/**
|
||
* GMainContextPusher:
|
||
*
|
||
* Opaque type. See g_main_context_pusher_new() for details.
|
||
*
|
||
* Since: 2.64
|
||
*/
|
||
typedef void GMainContextPusher GLIB_AVAILABLE_TYPE_IN_2_64;
|
||
|
||
/**
|
||
* g_main_context_pusher_new:
|
||
* @main_context: (transfer none): a main context to push
|
||
*
|
||
* Push @main_context as the new thread-default main context for the current
|
||
* thread, using g_main_context_push_thread_default(), and return a new
|
||
* #GMainContextPusher. Pop with g_main_context_pusher_free(). Using
|
||
* g_main_context_pop_thread_default() on @main_context while a
|
||
* #GMainContextPusher exists for it can lead to undefined behaviour.
|
||
*
|
||
* Using two #GMainContextPushers in the same scope is not allowed, as it leads
|
||
* to an undefined pop order.
|
||
*
|
||
* This is intended to be used with g_autoptr(). Note that g_autoptr()
|
||
* is only available when using GCC or clang, so the following example
|
||
* will only work with those compilers:
|
||
* |[
|
||
* typedef struct
|
||
* {
|
||
* ...
|
||
* GMainContext *context;
|
||
* ...
|
||
* } MyObject;
|
||
*
|
||
* static void
|
||
* my_object_do_stuff (MyObject *self)
|
||
* {
|
||
* g_autoptr(GMainContextPusher) pusher = g_main_context_pusher_new (self->context);
|
||
*
|
||
* // Code with main context as the thread default here
|
||
*
|
||
* if (cond)
|
||
* // No need to pop
|
||
* return;
|
||
*
|
||
* // Optionally early pop
|
||
* g_clear_pointer (&pusher, g_main_context_pusher_free);
|
||
*
|
||
* // Code with main context no longer the thread default here
|
||
* }
|
||
* ]|
|
||
*
|
||
* Returns: (transfer full): a #GMainContextPusher
|
||
* Since: 2.64
|
||
*/
|
||
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
|
||
GLIB_AVAILABLE_STATIC_INLINE_IN_2_64
|
||
static inline GMainContextPusher *
|
||
g_main_context_pusher_new (GMainContext *main_context)
|
||
{
|
||
g_main_context_push_thread_default (main_context);
|
||
return (GMainContextPusher *) main_context;
|
||
}
|
||
G_GNUC_END_IGNORE_DEPRECATIONS
|
||
|
||
/**
|
||
* g_main_context_pusher_free:
|
||
* @pusher: (transfer full): a #GMainContextPusher
|
||
*
|
||
* Pop @pusher’s main context as the thread default main context.
|
||
* See g_main_context_pusher_new() for details.
|
||
*
|
||
* This will pop the #GMainContext as the current thread-default main context,
|
||
* but will not call g_main_context_unref() on it.
|
||
*
|
||
* Since: 2.64
|
||
*/
|
||
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
|
||
GLIB_AVAILABLE_STATIC_INLINE_IN_2_64
|
||
static inline void
|
||
g_main_context_pusher_free (GMainContextPusher *pusher)
|
||
{
|
||
g_main_context_pop_thread_default ((GMainContext *) pusher);
|
||
}
|
||
G_GNUC_END_IGNORE_DEPRECATIONS
|
||
|
||
/* GMainLoop: */
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainLoop *g_main_loop_new (GMainContext *context,
|
||
gboolean is_running);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_loop_run (GMainLoop *loop);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_loop_quit (GMainLoop *loop);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainLoop *g_main_loop_ref (GMainLoop *loop);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_loop_unref (GMainLoop *loop);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_main_loop_is_running (GMainLoop *loop);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainContext *g_main_loop_get_context (GMainLoop *loop);
|
||
|
||
/* GSource: */
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_source_new (GSourceFuncs *source_funcs,
|
||
guint struct_size);
|
||
|
||
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
|
||
GLIB_AVAILABLE_IN_2_64
|
||
void g_source_set_dispose_function (GSource *source,
|
||
GSourceDisposeFunc dispose);
|
||
G_GNUC_END_IGNORE_DEPRECATIONS
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_source_ref (GSource *source);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_unref (GSource *source);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_source_attach (GSource *source,
|
||
GMainContext *context);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_destroy (GSource *source);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_set_priority (GSource *source,
|
||
gint priority);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gint g_source_get_priority (GSource *source);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_set_can_recurse (GSource *source,
|
||
gboolean can_recurse);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_source_get_can_recurse (GSource *source);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_source_get_id (GSource *source);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GMainContext *g_source_get_context (GSource *source);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_set_callback (GSource *source,
|
||
GSourceFunc func,
|
||
gpointer data,
|
||
GDestroyNotify notify);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_set_funcs (GSource *source,
|
||
GSourceFuncs *funcs);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_source_is_destroyed (GSource *source);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_set_name (GSource *source,
|
||
const char *name);
|
||
GLIB_AVAILABLE_IN_2_70
|
||
void g_source_set_static_name (GSource *source,
|
||
const char *name);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
const char * g_source_get_name (GSource *source);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_set_name_by_id (guint tag,
|
||
const char *name);
|
||
|
||
GLIB_AVAILABLE_IN_2_36
|
||
void g_source_set_ready_time (GSource *source,
|
||
gint64 ready_time);
|
||
GLIB_AVAILABLE_IN_2_36
|
||
gint64 g_source_get_ready_time (GSource *source);
|
||
|
||
#ifdef G_OS_UNIX
|
||
GLIB_AVAILABLE_IN_2_36
|
||
gpointer g_source_add_unix_fd (GSource *source,
|
||
gint fd,
|
||
GIOCondition events);
|
||
GLIB_AVAILABLE_IN_2_36
|
||
void g_source_modify_unix_fd (GSource *source,
|
||
gpointer tag,
|
||
GIOCondition new_events);
|
||
GLIB_AVAILABLE_IN_2_36
|
||
void g_source_remove_unix_fd (GSource *source,
|
||
gpointer tag);
|
||
GLIB_AVAILABLE_IN_2_36
|
||
GIOCondition g_source_query_unix_fd (GSource *source,
|
||
gpointer tag);
|
||
#endif
|
||
|
||
/* Used to implement g_source_connect_closure and internally*/
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_set_callback_indirect (GSource *source,
|
||
gpointer callback_data,
|
||
GSourceCallbackFuncs *callback_funcs);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_add_poll (GSource *source,
|
||
GPollFD *fd);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_remove_poll (GSource *source,
|
||
GPollFD *fd);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_add_child_source (GSource *source,
|
||
GSource *child_source);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_source_remove_child_source (GSource *source,
|
||
GSource *child_source);
|
||
|
||
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
|
||
GLIB_DEPRECATED_IN_2_28_FOR(g_source_get_time)
|
||
void g_source_get_current_time (GSource *source,
|
||
GTimeVal *timeval);
|
||
G_GNUC_END_IGNORE_DEPRECATIONS
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gint64 g_source_get_time (GSource *source);
|
||
|
||
/* void g_source_connect_closure (GSource *source,
|
||
GClosure *closure);
|
||
*/
|
||
|
||
/* Specific source types
|
||
*/
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_idle_source_new (void);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_child_watch_source_new (GPid pid);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_timeout_source_new (guint interval);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
GSource *g_timeout_source_new_seconds (guint interval);
|
||
|
||
/* Miscellaneous functions
|
||
*/
|
||
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
|
||
GLIB_DEPRECATED_IN_2_62_FOR(g_get_real_time)
|
||
void g_get_current_time (GTimeVal *result);
|
||
G_GNUC_END_IGNORE_DEPRECATIONS
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gint64 g_get_monotonic_time (void);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gint64 g_get_real_time (void);
|
||
|
||
|
||
/* Source manipulation by ID */
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_source_remove (guint tag);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_source_remove_by_user_data (gpointer user_data);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
|
||
gpointer user_data);
|
||
|
||
/**
|
||
* GClearHandleFunc:
|
||
* @handle_id: the handle ID to clear
|
||
*
|
||
* Specifies the type of function passed to g_clear_handle_id().
|
||
* The implementation is expected to free the resource identified
|
||
* by @handle_id; for instance, if @handle_id is a #GSource ID,
|
||
* g_source_remove() can be used.
|
||
*
|
||
* Since: 2.56
|
||
*/
|
||
typedef void (* GClearHandleFunc) (guint handle_id);
|
||
|
||
GLIB_AVAILABLE_IN_2_56
|
||
void g_clear_handle_id (guint *tag_ptr,
|
||
GClearHandleFunc clear_func);
|
||
|
||
#define g_clear_handle_id(tag_ptr, clear_func) \
|
||
G_STMT_START { \
|
||
G_STATIC_ASSERT (sizeof *(tag_ptr) == sizeof (guint)); \
|
||
guint *_tag_ptr = (guint *) (tag_ptr); \
|
||
guint _handle_id; \
|
||
\
|
||
_handle_id = *_tag_ptr; \
|
||
if (_handle_id > 0) \
|
||
{ \
|
||
*_tag_ptr = 0; \
|
||
clear_func (_handle_id); \
|
||
} \
|
||
} G_STMT_END \
|
||
GLIB_AVAILABLE_MACRO_IN_2_56
|
||
|
||
/* Idles, child watchers and timeouts */
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_timeout_add_full (gint priority,
|
||
guint interval,
|
||
GSourceFunc function,
|
||
gpointer data,
|
||
GDestroyNotify notify);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_timeout_add (guint interval,
|
||
GSourceFunc function,
|
||
gpointer data);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_timeout_add_seconds_full (gint priority,
|
||
guint interval,
|
||
GSourceFunc function,
|
||
gpointer data,
|
||
GDestroyNotify notify);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_timeout_add_seconds (guint interval,
|
||
GSourceFunc function,
|
||
gpointer data);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_child_watch_add_full (gint priority,
|
||
GPid pid,
|
||
GChildWatchFunc function,
|
||
gpointer data,
|
||
GDestroyNotify notify);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_child_watch_add (GPid pid,
|
||
GChildWatchFunc function,
|
||
gpointer data);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_idle_add (GSourceFunc function,
|
||
gpointer data);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
guint g_idle_add_full (gint priority,
|
||
GSourceFunc function,
|
||
gpointer data,
|
||
GDestroyNotify notify);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
gboolean g_idle_remove_by_data (gpointer data);
|
||
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_invoke_full (GMainContext *context,
|
||
gint priority,
|
||
GSourceFunc function,
|
||
gpointer data,
|
||
GDestroyNotify notify);
|
||
GLIB_AVAILABLE_IN_ALL
|
||
void g_main_context_invoke (GMainContext *context,
|
||
GSourceFunc function,
|
||
gpointer data);
|
||
|
||
GLIB_AVAILABLE_STATIC_INLINE_IN_2_70
|
||
static inline int
|
||
g_steal_fd (int *fd_ptr)
|
||
{
|
||
int fd = *fd_ptr;
|
||
*fd_ptr = -1;
|
||
return fd;
|
||
}
|
||
|
||
/* Hook for GClosure / GSource integration. Don't touch */
|
||
GLIB_VAR GSourceFuncs g_timeout_funcs;
|
||
GLIB_VAR GSourceFuncs g_child_watch_funcs;
|
||
GLIB_VAR GSourceFuncs g_idle_funcs;
|
||
#ifdef G_OS_UNIX
|
||
GLIB_VAR GSourceFuncs g_unix_signal_funcs;
|
||
GLIB_VAR GSourceFuncs g_unix_fd_source_funcs;
|
||
#endif
|
||
|
||
G_END_DECLS
|
||
|
||
#endif /* __G_MAIN_H__ */
|