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/*
* (C) COPYRIGHT ARM Limited. All rights reserved.
*
* This program is free software and is provided to you under the terms of the
* GNU General Public License version 2 as published by the Free Software
* Foundation, and any use by you of this program is subject to the terms
* of such GNU licence.
*
* A copy of the licence is included with the program, and can also be obtained
* from Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#ifndef MVE_RSRC_CIRCULAR_BUFFER
#define MVE_RSRC_CIRCULAR_BUFFER
#ifdef EMULATOR
#include "emulator_userspace.h"
#else
#include <linux/types.h>
#endif
/**
* Structure used to represent a circular buffer.
*/
struct mver_circular_buffer
{
uint32_t size; /**< Number of 32-bit entries in the circular buffer */
uint32_t r_pos; /**< Tail position (read position) */
uint32_t w_pos; /**< Head position (write position) */
void **data; /**< Pointer to the actual circular buffer */
};
/**
* Iterate over all elements in the circular buffer.
*/
#define mver_circular_buffer_for_each(index, ptr, type, cb) \
for (index = 0; ptr = (type)cb->data[(cb->r_pos + index) % cb->size], index < mver_circular_buffer_get_num_entries(cb); ++index)
/**
* Create a circular buffer of the given size.
* @param size Number of 32-bit elements in the circular buffer.
* @return Pointer to an initialized mver_circular_buffer, NULL on failure
*/
struct mver_circular_buffer *mver_circular_buffer_create(uint32_t size);
/**
* Destroy a circular buffer. Frees all resources that were allocated during
* the creation of the circular buffer. Note that the elements themselves are
* not freed.
* @param cb The circular buffer to destroy
*/
void mver_circular_buffer_destroy(struct mver_circular_buffer *cb);
/**
* Add an element to the circular buffer.
* @param cb The circular buffer to add the element to
* @param item The item to add to the circular buffer
* @return True on success, false if the element couldn't be added
*/
bool mver_circular_buffer_add(struct mver_circular_buffer *cb, void *item);
/**
* Remove the tail element in the circular buffer and return it.
* @param cb The circular buffer
* @param data This pointer will point to the removed element
* @return True if an element was removed. False if the circular buffer was empty
*/
bool mver_circular_buffer_remove(struct mver_circular_buffer *cb, void **data);
/**
* Get the number of items in the circular buffer.
* @param cb The circular buffer
* @return The number of items in the circular buffer
*/
uint32_t mver_circular_buffer_get_num_entries(struct mver_circular_buffer *cb);
/**
* Get the tail element without removing it from the circular buffer.
* @param cb The circular buffer
* @param data This pointer will point to the tail element
* @return True if the circular buffer contains atleast one element, false otherwise
*/
bool mver_circular_buffer_peek(struct mver_circular_buffer *cb, void **data);
/**
* Remove all occurances of a certain item.
* @param cb The circular buffer
* @param data The item to be removed
*/
void mver_circular_buffer_remove_all_occurences(struct mver_circular_buffer *cb, void *data);
#endif /* MVE_RSRC_CIRCULAR_BUFFER */
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