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/* -*- Mode: C ; c-basic-offset: 2 -*- */
/*****************************************************************************
*
* This file is part of lv2dynparam libraries
*
* Copyright (C) 2006,2007,2008,2009 Nedko Arnaudov <nedko@arnaudov.name>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
*****************************************************************************/
/* For supporting philosophy look at article at
* http://nedko.arnaudov.name/wiki/moin.cgi/Accessing_data_from_audio_process_thread_and_UI_thread */
#include <pthread.h>
#include <assert.h>
#include <stdlib.h>
#include <errno.h>
#include "audiolock.h"
struct audiolock
{
pthread_mutex_t mutex;
};
audiolock_handle audiolock_create_optimistic()
{
return AUDIOLOCK_HANDLE_INVALID_VALUE; /* not implemented */
}
audiolock_handle audiolock_create_pessimistic()
{
return AUDIOLOCK_HANDLE_INVALID_VALUE; /* not implemented */
}
audiolock_handle audiolock_create_slow()
{
struct audiolock * audiolock_ptr;
audiolock_ptr = malloc(sizeof(struct audiolock));
if (audiolock_ptr == NULL)
{
return AUDIOLOCK_HANDLE_INVALID_VALUE;
}
pthread_mutex_init(&audiolock_ptr->mutex, NULL);
return (audiolock_handle)audiolock_ptr;
}
#define audiolock_ptr ((struct audiolock *)lock)
int audiolock_enter_audio(audiolock_handle lock)
{
int error;
error = pthread_mutex_trylock(&audiolock_ptr->mutex);
if (error == 0)
{
return 1;
}
assert(error == EBUSY);
return 0;
}
void audiolock_leave_audio(audiolock_handle lock)
{
pthread_mutex_unlock(&audiolock_ptr->mutex);
}
void audiolock_enter_ui(audiolock_handle lock)
{
pthread_mutex_lock(&audiolock_ptr->mutex);
}
void audiolock_leave_ui(audiolock_handle lock)
{
pthread_mutex_unlock(&audiolock_ptr->mutex);
}
void audiolock_destroy(audiolock_handle lock)
{
int error;
error = pthread_mutex_destroy(&audiolock_ptr->mutex);
assert(error == 0); /* destroy should fail only if mutex is currently locked */
if (error != 0)
{
return;
}
free(audiolock_ptr);
}
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