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/* Copyright (c) 2015, The Linux Foundation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
* * Neither the name of The Linux Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
* IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __RING_BUFFER_H
#define __RING_BUFFER_H
/* Ring buffer status codes */
enum rb_status {
RB_SUCCESS = 0,
RB_FAILURE = 1,
RB_FULL = 2,
RB_RETRY = 3,
};
struct rb_stats {
u32 total_bytes_written;
u32 total_bytes_read;
u32 cur_valid_bytes;
unsigned int max_num_bufs;
size_t each_buf_size;
};
typedef void (*threshold_call_back) (void *cb_ctx);
/* intiitalizes the ring buffer and returns the context to it */
void * ring_buffer_init(size_t size_of_buf, int num_bufs);
/* Frees up the mem allocated for this ring buffer operation */
void ring_buffer_deinit(void *ctx);
/* Writes writes length of bytes from buf to ring buffer */
enum rb_status rb_write(void *ctx, u8 *buf, size_t length, int overwrite,
size_t record_length);
/* Tries to read max_length of bytes from ring buffer to buf
* and returns actual length of bytes read from ring buffer
*/
size_t rb_read(void *ctx, u8 *buf, size_t max_length);
/* A buffer with possible maximum of bytes that can be read
* from a single buffer of ring buffer
* Ring buffer module looses the ownership of the buffer returned by this api,
* which means the caller has to make sure to free the buffer returned.
*/
u8 *rb_get_read_buf(void *ctx, size_t *length);
/* calls callback whenever ring_buffer reaches percent percentage of it'ss
* full size
*/
void rb_config_threshold(void *ctx,
unsigned int num_min_bytes,
threshold_call_back callback,
void *cb_ctx);
/* Get the current status of ring buffer */
void rb_get_stats(void *ctx, struct rb_stats *rbs);
#endif /* __RING_BUFFER_H */
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