gstreamer/omx/gstomxrecmutex.c
2012-11-12 11:29:48 +01:00

97 lines
2.5 KiB
C

/*
* Copyright (C) 2012, Collabora Ltd.
* Author: George Kiagiadakis <george.kiagiadakis@collabora.com>
*
* 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
* version 2.1 of the License.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstomxrecmutex.h"
void
gst_omx_rec_mutex_init (GstOMXRecMutex * mutex)
{
g_mutex_init (&mutex->lock);
g_mutex_init (&mutex->recursion_lock);
mutex->recursion_allowed = FALSE;
}
void
gst_omx_rec_mutex_clear (GstOMXRecMutex * mutex)
{
g_mutex_clear (&mutex->lock);
g_mutex_clear (&mutex->recursion_lock);
}
void
gst_omx_rec_mutex_lock (GstOMXRecMutex * mutex)
{
g_mutex_lock (&mutex->lock);
}
void
gst_omx_rec_mutex_unlock (GstOMXRecMutex * mutex)
{
g_mutex_unlock (&mutex->lock);
}
/* must be called with mutex->lock taken */
void
gst_omx_rec_mutex_begin_recursion (GstOMXRecMutex * mutex)
{
g_mutex_lock (&mutex->recursion_lock);
g_assert (mutex->recursion_allowed == FALSE);
mutex->recursion_allowed = TRUE;
g_mutex_unlock (&mutex->recursion_lock);
}
/* must be called with mutex->lock taken */
void
gst_omx_rec_mutex_end_recursion (GstOMXRecMutex * mutex)
{
g_mutex_lock (&mutex->recursion_lock);
g_assert (mutex->recursion_allowed == TRUE);
mutex->recursion_allowed = FALSE;
g_mutex_unlock (&mutex->recursion_lock);
}
void
gst_omx_rec_mutex_recursive_lock (GstOMXRecMutex * mutex)
{
g_mutex_lock (&mutex->recursion_lock);
if (!mutex->recursion_allowed) {
/* no recursion allowed, lock the proper mutex */
g_mutex_unlock (&mutex->recursion_lock);
g_mutex_lock (&mutex->lock);
}
}
void
gst_omx_rec_mutex_recursive_unlock (GstOMXRecMutex * mutex)
{
/* It is safe to check recursion_allowed here because
* we hold at least one of the two locks and
* either lock protects it from being changed.
*/
if (mutex->recursion_allowed) {
g_mutex_unlock (&mutex->recursion_lock);
} else {
g_mutex_unlock (&mutex->lock);
}
}