gstreamer/gst/gsttask.h
Nicolas Dufresne e272ae281f task: Introduce gst_task_resume() API
This new API allow resuming a task if it was paused, while leaving it to
stopped stated if it was stopped or not started yet. This new API can be
useful for callback driver workflow, where you basically want to pause and
resume the task when buffers are notified while avoiding the race with a
gst_task_stop() coming from another thread.
2020-04-01 15:13:59 +00:00

220 lines
6.1 KiB
C

/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
* <2005> Wim Taymans <wim@fluendo.com>
*
* gsttask.h: Streaming tasks
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef __GST_TASK_H__
#define __GST_TASK_H__
#include <gst/gstobject.h>
#include <gst/gsttaskpool.h>
G_BEGIN_DECLS
/**
* GstTaskFunction:
* @user_data: user data passed to the function
*
* A function that will repeatedly be called in the thread created by
* a #GstTask.
*/
typedef void (*GstTaskFunction) (gpointer user_data);
/* --- standard type macros --- */
#define GST_TYPE_TASK (gst_task_get_type ())
#define GST_TASK(task) (G_TYPE_CHECK_INSTANCE_CAST ((task), GST_TYPE_TASK, GstTask))
#define GST_IS_TASK(task) (G_TYPE_CHECK_INSTANCE_TYPE ((task), GST_TYPE_TASK))
#define GST_TASK_CLASS(tclass) (G_TYPE_CHECK_CLASS_CAST ((tclass), GST_TYPE_TASK, GstTaskClass))
#define GST_IS_TASK_CLASS(tclass) (G_TYPE_CHECK_CLASS_TYPE ((tclass), GST_TYPE_TASK))
#define GST_TASK_GET_CLASS(task) (G_TYPE_INSTANCE_GET_CLASS ((task), GST_TYPE_TASK, GstTaskClass))
#define GST_TASK_CAST(task) ((GstTask*)(task))
typedef struct _GstTask GstTask;
typedef struct _GstTaskClass GstTaskClass;
typedef struct _GstTaskPrivate GstTaskPrivate;
/**
* GstTaskState:
* @GST_TASK_STARTED: the task is started and running
* @GST_TASK_STOPPED: the task is stopped
* @GST_TASK_PAUSED: the task is paused
*
* The different states a task can be in
*/
typedef enum {
GST_TASK_STARTED,
GST_TASK_STOPPED,
GST_TASK_PAUSED
} GstTaskState;
/**
* GST_TASK_STATE:
* @task: Task to get the state of
*
* Get access to the state of the task.
*/
#define GST_TASK_STATE(task) (GST_TASK_CAST(task)->state)
/**
* GST_TASK_GET_COND:
* @task: Task to get the cond of
*
* Get access to the cond of the task.
*/
#define GST_TASK_GET_COND(task) (&GST_TASK_CAST(task)->cond)
/**
* GST_TASK_WAIT:
* @task: Task to wait for
*
* Wait for the task cond to be signalled
*/
#define GST_TASK_WAIT(task) g_cond_wait(GST_TASK_GET_COND (task), GST_OBJECT_GET_LOCK (task))
/**
* GST_TASK_SIGNAL:
* @task: Task to signal
*
* Signal the task cond
*/
#define GST_TASK_SIGNAL(task) g_cond_signal(GST_TASK_GET_COND (task))
/**
* GST_TASK_BROADCAST:
* @task: Task to broadcast
*
* Send a broadcast signal to all waiting task conds
*/
#define GST_TASK_BROADCAST(task) g_cond_broadcast(GST_TASK_GET_COND (task))
/**
* GST_TASK_GET_LOCK:
* @task: Task to get the lock of
*
* Get access to the task lock.
*/
#define GST_TASK_GET_LOCK(task) (GST_TASK_CAST(task)->lock)
/**
* GstTaskThreadFunc:
* @task: The #GstTask
* @thread: The #GThread
* @user_data: user data
*
* Custom GstTask thread callback functions that can be installed.
*/
typedef void (*GstTaskThreadFunc) (GstTask *task, GThread *thread, gpointer user_data);
/**
* GstTask:
* @state: the state of the task
* @cond: used to pause/resume the task
* @lock: The lock taken when iterating the task function
* @func: the function executed by this task
* @user_data: user_data passed to the task function
* @notify: GDestroyNotify for @user_data
* @running: a flag indicating that the task is running
*
* The #GstTask object.
*/
struct _GstTask {
GstObject object;
/*< public >*/ /* with LOCK */
GstTaskState state;
GCond cond;
GRecMutex *lock;
GstTaskFunction func;
gpointer user_data;
GDestroyNotify notify;
gboolean running;
/*< private >*/
GThread *thread;
GstTaskPrivate *priv;
gpointer _gst_reserved[GST_PADDING];
};
struct _GstTaskClass {
GstObjectClass parent_class;
/*< private >*/
GstTaskPool *pool;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
GST_API
void gst_task_cleanup_all (void);
GST_API
GType gst_task_get_type (void);
GST_API
GstTask* gst_task_new (GstTaskFunction func,
gpointer user_data, GDestroyNotify notify);
GST_API
void gst_task_set_lock (GstTask *task, GRecMutex *mutex);
GST_API
GstTaskPool * gst_task_get_pool (GstTask *task);
GST_API
void gst_task_set_pool (GstTask *task, GstTaskPool *pool);
GST_API
void gst_task_set_enter_callback (GstTask *task,
GstTaskThreadFunc enter_func,
gpointer user_data,
GDestroyNotify notify);
GST_API
void gst_task_set_leave_callback (GstTask *task,
GstTaskThreadFunc leave_func,
gpointer user_data,
GDestroyNotify notify);
GST_API
GstTaskState gst_task_get_state (GstTask *task);
GST_API
gboolean gst_task_set_state (GstTask *task, GstTaskState state);
GST_API
gboolean gst_task_start (GstTask *task);
GST_API
gboolean gst_task_stop (GstTask *task);
GST_API
gboolean gst_task_pause (GstTask *task);
GST_API
gboolean gst_task_resume (GstTask *task);
GST_API
gboolean gst_task_join (GstTask *task);
G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstTask, gst_object_unref)
G_END_DECLS
#endif /* __GST_TASK_H__ */