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/*
*
* AT chat library with GLib integration
*
* Copyright (C) 2008-2009 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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
*
*/
#ifndef __GATCHAT_RINGBUFFER_H
#define __GATCHAT_RINGBUFFER_H
#ifdef __cplusplus
extern "C" {
#endif
struct ring_buffer {
unsigned char *buffer;
unsigned int size;
unsigned int in;
unsigned int out;
};
/*!
* Creates a new ring buffer with capacity size
*/
struct ring_buffer *ring_buffer_new(unsigned int size);
/*!
* Frees the resources allocated for the ring buffer
*/
void ring_buffer_free(struct ring_buffer *buf);
/*!
* Returns the capacity of the ring buffer
*/
int ring_buffer_capacity(struct ring_buffer *buf);
/*!
* Resets the ring buffer, all data inside the buffer is lost
*/
void ring_buffer_reset(struct ring_buffer *buf);
/*!
* Writes data of size len into the ring buffer buf. Returns -1 if the
* write failed or the number of bytes written
*/
int ring_buffer_write(struct ring_buffer *buf, const void *data,
unsigned int len);
/*!
* Advances the write counter by len, this is meant to be used with
* the ring_buffer_write_ptr function. Returns the number of bytes
* actually advanced (the capacity of the buffer)
*/
int ring_buffer_write_advance(struct ring_buffer *buf, unsigned int len);
/*!
* Returns the write pointer. Careful not to write past the end of the
* buffer. Use the ring_buffer_avail_no_wrap function,
* ring_buffer_write_advance.
*/
unsigned char *ring_buffer_write_ptr(struct ring_buffer *buf);
/*!
* Returns the number of free bytes available in the buffer
*/
int ring_buffer_avail(struct ring_buffer *buf);
/*!
* Returns the number of free bytes available in the buffer without wrapping
*/
int ring_buffer_avail_no_wrap(struct ring_buffer *buf);
/*!
* Reads data from the ring buffer buf into memory region pointed to by data.
* A maximum of len bytes will be read. Returns -1 if the read failed or
* the number of bytes read
*/
int ring_buffer_read(struct ring_buffer *buf, void *data,
unsigned int len);
/*!
* Returns the read pointer with read offset specified by offset. No bounds
* checking is performed. Be careful not to read past the end of the buffer.
* Use the ring_buffer_len_no_wrap function, and ring_buffer_drain.
*/
unsigned char *ring_buffer_read_ptr(struct ring_buffer *buf,
unsigned int offset);
/*!
* Returns the number of bytes currently available to be read in the buffer
*/
int ring_buffer_len(struct ring_buffer *buf);
/*!
* Returns the number of bytes currently available to be read in the buffer
* without wrapping.
*/
int ring_buffer_len_no_wrap(struct ring_buffer *buf);
/*!
* Drains the ring buffer of len bytes. Returns the number of bytes the
* read counter was actually advanced.
*/
int ring_buffer_drain(struct ring_buffer *buf, unsigned int len);
#ifdef __cplusplus
}
#endif
#endif /* __GATCHAT_RINGBUFFER_H */
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