Adds child_source to source as a ‘polled’ source.
When source is added to a GLib.MainContext, child_source will be
automatically added with the same priority. When child_source is triggered,
it will cause source to dispatch (in addition to calling its own callback),
and when source is destroyed, it will destroy child_source as well.
The source will also still be dispatched if its own prepare/check functions
indicate that it is ready.
If you don’t need child_source to do anything on its own when it
triggers, you can call g_source_set_dummy_callback() on it to set a
callback that does nothing (except return true if appropriate).
The source will hold a reference on child_source while child_source
is attached to it.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
Adds a file descriptor to the set of file descriptors polled for this source.
This is usually combined with GLib.Source.new to add an
event source. The event source’s check function will typically test
the revents field in the GLib.PollFD struct and return true if
events need to be processed.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
Using this API forces the linear scanning of event sources on each
main loop iteration. Newly-written event sources should try to use
g_source_add_unix_fd() instead of this API.
a GLib.PollFD structure holding information about a file descriptor to watch
Monitors fd for the IO events in events.
The tag returned by this function can be used to remove or modify the
monitoring of the fd using GLib.Source.remove_unix_fd or
GLib.Source.modify_unix_fd.
It is not necessary to remove the file descriptor before destroying the source; it will be cleaned up automatically.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
As the name suggests, this function is not available on Windows.
the file descriptor to monitor
an event mask
an opaque tag
Adds a GLib.Source to a context so that it will be executed within
that context.
Remove it by calling GLib.Source.destroy.
This function is safe to call from any thread, regardless of which thread
the context is running in.
Optionalcontext: GLib.MainContexta main context (if NULL, the global-default main context will be used)
the ID (greater than 0) for the source within the GLib.MainContext
Removes a source from its GLib.MainContext, if any, and marks it as destroyed.
The source cannot be subsequently added to another context. It is safe to call this on sources which have already been removed from their context.
This does not unref the GLib.Source: if you still hold a reference, use GLib.Source.unref to drop it.
This function is safe to call from any thread, regardless of which thread the GLib.MainContext is running in.
If the source is currently attached to a GLib.MainContext, destroying it will effectively unset the callback similar to calling GLib.Source.set_callback. This can mean, that the data’s GLib.DestroyNotify gets called right away.
Gets a reference to the GLib.MainContext with which the source is associated.
You can call this on a source that has been destroyed. You can always call this function on the source returned from GLib.main_current_source.
the GLib.MainContext with which the source is associated, or NULL if the context has not yet been added to a source
Checks whether a source is allowed to be called recursively.
whether recursion is allowed
Gets the GLib.MainContext with which the source is associated.
You can call this on a source that has been destroyed, provided that the GLib.MainContext it was attached to still exists (in which case it will return that GLib.MainContext). In particular, you can always call this function on the source returned from GLib.main_current_source. But calling this function on a source whose GLib.MainContext has been destroyed is an error.
If the associated GLib.MainContext could be destroy concurrently from a different thread, then this function is not safe to call and GLib.Source.dup_context should be used instead.
the main context with which the source is associated, or NULL if the context has not yet been added to a source
This function ignores source and is otherwise the same as
GLib.get_current_time.
GLib.TimeVal structure in which to store current time
Returns the numeric ID for a particular source.
The ID of a source is a positive integer which is unique within a particular main loop context. The reverse mapping from ID to source is done by GLib.MainContext.find_source_by_id.
You can only call this function while the source is associated to a GLib.MainContext instance; calling this function before GLib.Source.attach or after GLib.Source.destroy yields undefined behavior. The ID returned is unique within the GLib.MainContext instance passed to GLib.Source.attach.
the ID (greater than 0) for the source
Gets a name for the source, used in debugging and profiling.
The
name may be NULL if it has never been set with GLib.Source.set_name.
the name of the source
Gets the priority of a source.
the priority of the source
Gets the ‘ready time’ of source, as set by
GLib.Source.set_ready_time.
Any time before or equal to the current monotonic time (including zero) is an indication that the source will fire immediately.
the monotonic ready time, -1 for ‘never’
Gets the time to be used when checking this source.
The advantage of calling this function over calling GLib.get_monotonic_time directly is that when checking multiple sources, GLib can cache a single value instead of having to repeatedly get the system monotonic time.
The time here is the system monotonic time, if available, or some other reasonable alternative otherwise. See GLib.get_monotonic_time.
the monotonic time in microseconds
Returns whether source has been destroyed.
This is important when you operate upon your objects from within idle handlers, but may have freed the object before the dispatch of your idle handler.
static gboolean
idle_callback (gpointer data)
{
SomeWidget *self = data;
g_mutex_lock (&self->idle_id_mutex);
// do stuff with self
self->idle_id = 0;
g_mutex_unlock (&self->idle_id_mutex);
return G_SOURCE_REMOVE;
}
static void
some_widget_do_stuff_later (SomeWidget *self)
{
g_mutex_lock (&self->idle_id_mutex);
self->idle_id = g_idle_add (idle_callback, self);
g_mutex_unlock (&self->idle_id_mutex);
}
static void
some_widget_init (SomeWidget *self)
{
g_mutex_init (&self->idle_id_mutex);
// ...
}
static void
some_widget_finalize (GObject *object)
{
SomeWidget *self = SOME_WIDGET (object);
if (self->idle_id)
g_source_remove (self->idle_id);
g_mutex_clear (&self->idle_id_mutex);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
This will fail in a multi-threaded application if the widget is destroyed before the idle handler fires due to the use after free in the callback. A solution, to this particular problem, is to check to if the source has already been destroy within the callback.
static gboolean
idle_callback (gpointer data)
{
SomeWidget *self = data;
g_mutex_lock (&self->idle_id_mutex);
if (!g_source_is_destroyed (g_main_current_source ()))
{
// do stuff with self
}
g_mutex_unlock (&self->idle_id_mutex);
return FALSE;
}
Calls to this function from a thread other than the one acquired by the GLib.MainContext the GLib.Source is attached to are typically redundant, as the source could be destroyed immediately after this function returns. However, once a source is destroyed it cannot be un-destroyed, so this function can be used for opportunistic checks from any thread.
true if the source has been destroyed, false otherwise
Updates the event mask to watch for the file descriptor identified by tag.
The tag is the tag returned from GLib.Source.add_unix_fd.
If you want to remove a file descriptor, don’t set its event mask to zero. Instead, call GLib.Source.remove_unix_fd.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
As the name suggests, this function is not available on Windows.
the tag from GLib.Source.add_unix_fd
the new event mask to watch
Queries the events reported for the file descriptor corresponding to tag
on source during the last poll.
The return value of this function is only defined when the function
is called from the check or dispatch functions for source.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
As the name suggests, this function is not available on Windows.
the tag from GLib.Source.add_unix_fd
the conditions reported on the file descriptor
Detaches child_source from source and destroys it.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
a source previously passed to GLib.Source.add_child_source
Removes a file descriptor from the set of file descriptors polled for this source.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
a GLib.PollFD structure previously passed to GLib.Source.add_poll
Reverses the effect of a previous call to GLib.Source.add_unix_fd.
You only need to call this if you want to remove a file descriptor from being watched while keeping the same source around. In the normal case you will just want to destroy the source.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
As the name suggests, this function is not available on Windows.
the tag from GLib.Source.add_unix_fd
Sets the callback function for a source. The callback for a source is called from the source’s dispatch function.
The exact type of func depends on the type of source; ie. you
should not count on func being called with data as its first
parameter. Cast func with GLib.SOURCE_FUNC to avoid warnings about
incompatible function types.
See main loop memory management for details
on how to handle memory management of data.
Typically, you won’t use this function. Instead use functions specific to the type of source you are using, such as GLib.idle_add or GLib.timeout_add.
It is safe to call this function multiple times on a source which has already been attached to a context. The changes will take effect for the next time the source is dispatched after this call returns.
Note that GLib.Source.destroy for a currently attached source has the effect of also unsetting the callback.
a callback function
Optionalnotify: DestroyNotifya function to call when data is no longer in use
Sets the callback function storing the data as a reference counted callback ‘object’.
This is used internally. Note that calling
GLib.Source.set_callback_indirect assumes
an initial reference count on callback_data, and thus
callback_funcs->unref will eventually be called once more than
callback_funcs->ref.
It is safe to call this function multiple times on a source which has already been attached to a context. The changes will take effect for the next time the source is dispatched after this call returns.
pointer to callback data ‘object’
functions for reference counting callback_data and getting the callback and data
Sets whether a source can be called recursively.
If can_recurse is true, then while the source is being dispatched then this
source will be processed normally. Otherwise, all processing of this
source is blocked until the dispatch function returns.
whether recursion is allowed for this source
Sets the source functions of an unattached source.
These can be used to override the default implementations for the type
of source.
the new source functions
Sets a name for the source, used in debugging and profiling.
The name defaults to NULL.
The source name should describe in a human-readable way what the source does. For example, ‘X11 event queue’ or ‘GTK repaint idle handler’.
It is permitted to call this function multiple times, but is not
recommended due to the potential performance impact. For example,
one could change the name in the check function of a
GLib.SourceFuncs to include details like the event type in the
source name.
Use caution if changing the name while another thread may be accessing it with GLib.Source.get_name; that function does not copy the value, and changing the value will free it while the other thread may be attempting to use it.
Also see GLib.Source.set_static_name.
debug name for the source
Sets the priority of a source.
While the main loop is being run, a source will be dispatched if it is ready to be dispatched and no sources at a higher (numerically smaller) priority are ready to be dispatched.
A child source always has the same priority as its parent. It is not permitted to change the priority of a source once it has been added as a child of another source.
the new priority
Sets a source to be dispatched when the given monotonic time is reached (or passed).
If the monotonic time is in the past (as it
always will be if ready_time is 0) then the source will be
dispatched immediately.
If ready_time is -1 then the source is never woken up on the basis
of the passage of time.
Dispatching the source does not reset the ready time. You should do so yourself, from the source dispatch function.
Note that if you have a pair of sources where the ready time of one suggests that it will be delivered first but the priority for the other suggests that it would be delivered first, and the ready time for both sources is reached during the same main context iteration, then the order of dispatch is undefined.
It is a no-op to call this function on a GLib.Source which has already been destroyed with GLib.Source.destroy.
This API is only intended to be used by implementations of GLib.Source. Do not call this API on a GLib.Source that you did not create.
the monotonic time at which the source will be ready; 0 for ‘immediately’, -1 for ‘never’
A variant of GLib.Source.set_name that does not
duplicate the name, and can only be used with
string literals.
debug name for the source
Decreases the reference count of a source by one.
If the resulting reference count is zero the source and associated memory will be destroyed.
StaticnewStaticremoveRemoves the source with the given ID from the default main context.
You must use GLib.Source.destroy for sources added to a non-default main context.
The ID of a GLib.Source is given by GLib.Source.get_id, or will be returned by the functions GLib.Source.attach, GLib.idle_add, GLib.idle_add_full, GLib.timeout_add, GLib.timeout_add_full, GLib.child_watch_add, GLib.child_watch_add_full, GLib.io_add_watch, and GLib.io_add_watch_full.
It is a programmer error to attempt to remove a non-existent source.
More specifically: source IDs can be reissued after a source has been destroyed and therefore it is never valid to use this function with a source ID which may have already been removed. An example is when scheduling an idle to run in another thread with GLib.idle_add: the idle may already have run and been removed by the time this function is called on its (now invalid) source ID. This source ID may have been reissued, leading to the operation being performed against the wrong source.
the ID of the source to remove.
Staticremove_Removes a source from the default main loop context given the source functions and user data.
If multiple sources exist with the same source functions and user data, only one will be destroyed.
the source_funcs passed to GLib.Source.new
Optionaluser_data: anythe user data for the callback
Staticremove_Removes a source from the default main loop context given the user data for the callback.
If multiple sources exist with the same user data, only one will be destroyed.
Optionaluser_data: anythe user_data for the callback
Staticset_Sets the name of a source using its ID.
This is a convenience utility to set source names from the return value of GLib.idle_add, GLib.timeout_add, etc.
It is a programmer error to attempt to set the name of a non-existent source.
More specifically: source IDs can be reissued after a source has been destroyed and therefore it is never valid to use this function with a source ID which may have already been removed. An example is when scheduling an idle to run in another thread with GLib.idle_add: the idle may already have run and been removed by the time this function is called on its (now invalid) source ID. This source ID may have been reissued, leading to the operation being performed against the wrong source.
a source ID
debug name for the source
The GLib.Source struct is an opaque data type representing an event source.