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#ifndef PA_RINGBUFFER_H
#define PA_RINGBUFFER_H
/*
* Portable Audio I/O Library
* Ring Buffer utility.
*
* Author: Phil Burk, http://www.softsynth.com
* modified for SMP safety on OS X by Bjorn Roche.
* also allowed for const where possible.
*
* Note that this is safe only for a single-thread reader
* and a single-thread writer.
*
* This program is distributed with the PortAudio Portable Audio Library.
* For more information see: http://www.portaudio.com
* Copyright (c) 1999-2000 Ross Bencina and Phil Burk
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/* derived from http://www.portaudio.com/trac/browser/portaudio/branches/v19-devel/src/common/pa_ringbuffer.h */
#include <sys/types.h>
#if defined(__GNUC__)
# if defined(__PPC__)
# define ring_fmb() asm volatile("sync":::"memory")
# define ring_rmb() asm volatile("sync":::"memory")
# define ring_wmb() asm volatile("sync":::"memory")
# elif defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__) || defined(__x86_64__)
# define ring_fmb() asm volatile("mfence":::"memory")
# define ring_rmb() asm volatile("lfence":::"memory")
# define ring_wmb() asm volatile("sfence":::"memory")
# elif (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)
# define ring_fmb() __sync_synchronize()
# define ring_rmb() __sync_synchronize()
# define ring_wmb() __sync_synchronize()
# else
# define ring_fmb()
# define ring_rmb()
# define ring_wmb()
# endif
#endif
typedef struct ring
{
size_t buffer_size;
size_t write_idx;
size_t read_idx;
size_t big_mask;
size_t small_mask;
char *buffer;
} ring_t;
ring_t *ring_new(size_t sz);
size_t ring_advance_read_idx(ring_t *rbuf, size_t sz);
size_t ring_advance_write_idx(ring_t *rbuf, size_t sz);
size_t ring_get_read_regions(ring_t *rbuf, size_t sz, void **dataPtr1, size_t *sizePtr1, void **dataPtr2, size_t *sizePtr2);
size_t ring_get_write_regions(ring_t *rbuf, size_t sz, void **dataPtr1, size_t *sizePtr1, void **dataPtr2, size_t *sizePtr2);
size_t ring_read(ring_t *rbuf, void *data, size_t sz);
size_t ring_read_bytes_avail(ring_t *rbuf);
size_t ring_write(ring_t *rbuf, const void *data, size_t sz);
size_t ring_write_bytes_avail(ring_t *rbuf);
void ring_flush(ring_t *rbuf);
#endif
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