ring_buffer.h

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/* ring_buffer.h: Simple ring buffer API */
 
/*
 * Copyright (c) 2015 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#ifndef ZEPHYR_INCLUDE_SYS_RING_BUFFER_H_
#define ZEPHYR_INCLUDE_SYS_RING_BUFFER_H_
 
#include <kernel.h>
#include <sys/util.h>
#include <errno.h>
#include <string.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
#define SIZE32_OF(x) (sizeof((x))/sizeof(uint32_t))
 
/* The limit is used by algorithm for distinguishing between empty and full
 * state.
 */
#define RING_BUFFER_MAX_SIZE 0x80000000
 
#define RING_BUFFER_SIZE_ASSERT_MSG \
        "Size too big, if it is the ring buffer test check custom max size"
struct ring_buf {
        uint32_t head;   
        uint32_t tail;   
        union ring_buf_misc {
                struct ring_buf_misc_item_mode {
                        uint32_t dropped_put_count; 
                } item_mode;
                struct ring_buf_misc_byte_mode {
                        uint32_t tmp_tail;
                        uint32_t tmp_head;
                } byte_mode;
        } misc;
        uint32_t size;   
        union ring_buf_buffer {
                uint32_t *buf32; 
                uint8_t *buf8;
        } buf;
        uint32_t mask;   
        struct k_spinlock lock;
};
 
#define RING_BUF_ITEM_DECLARE_POW2(name, pow) \
        BUILD_ASSERT((1 << pow) < RING_BUFFER_MAX_SIZE,\
                RING_BUFFER_SIZE_ASSERT_MSG); \
        static uint32_t __noinit _ring_buffer_data_##name[BIT(pow)]; \
        struct ring_buf name = { \
                .size = (BIT(pow)),       \
                .mask = (BIT(pow)) - 1, \
                .buf = { .buf32 = _ring_buffer_data_##name } \
        }
 
#define RING_BUF_ITEM_DECLARE_SIZE(name, size32) \
        BUILD_ASSERT(size32 < RING_BUFFER_MAX_SIZE,\
                RING_BUFFER_SIZE_ASSERT_MSG); \
        static uint32_t __noinit _ring_buffer_data_##name[size32]; \
        struct ring_buf name = { \
                .size = size32, \
                .buf = { .buf32 = _ring_buffer_data_##name} \
        }
 
#define RING_BUF_DECLARE(name, size8) \
        BUILD_ASSERT(size8 < RING_BUFFER_MAX_SIZE,\
                RING_BUFFER_SIZE_ASSERT_MSG); \
        static uint8_t __noinit _ring_buffer_data_##name[size8]; \
        struct ring_buf name = { \
                .size = size8, \
                .buf = { .buf8 = _ring_buffer_data_##name} \
        }
 
 
static inline void ring_buf_init(struct ring_buf *buf,
                                 uint32_t size,
                                 void *data)
{
        __ASSERT(size < RING_BUFFER_MAX_SIZE, RING_BUFFER_SIZE_ASSERT_MSG);
 
        memset(buf, 0, sizeof(struct ring_buf));
        buf->size = size;
        buf->buf.buf32 = (uint32_t *)data;
        if (is_power_of_two(size)) {
                buf->mask = size - 1U;
        } else {
                buf->mask = 0U;
        }
}
 
int ring_buf_is_empty(struct ring_buf *buf);
 
static inline void ring_buf_reset(struct ring_buf *buf)
{
        buf->head = 0;
        buf->tail = 0;
        memset(&buf->misc, 0, sizeof(buf->misc));
}
 
uint32_t ring_buf_space_get(struct ring_buf *buf);
 
static inline uint32_t ring_buf_capacity_get(struct ring_buf *buf)
{
        return buf->size;
}
 
uint32_t ring_buf_size_get(struct ring_buf *buf);
 
int ring_buf_item_put(struct ring_buf *buf, uint16_t type, uint8_t value,
                      uint32_t *data, uint8_t size32);
 
int ring_buf_item_get(struct ring_buf *buf, uint16_t *type, uint8_t *value,
                      uint32_t *data, uint8_t *size32);
 
uint32_t ring_buf_put_claim(struct ring_buf *buf,
                            uint8_t **data,
                            uint32_t size);
 
int ring_buf_put_finish(struct ring_buf *buf, uint32_t size);
 
uint32_t ring_buf_put(struct ring_buf *buf, const uint8_t *data, uint32_t size);
 
uint32_t ring_buf_get_claim(struct ring_buf *buf,
                            uint8_t **data,
                            uint32_t size);
 
int ring_buf_get_finish(struct ring_buf *buf, uint32_t size);
 
uint32_t ring_buf_get(struct ring_buf *buf, uint8_t *data, uint32_t size);
 
uint32_t ring_buf_peek(struct ring_buf *buf, uint8_t *data, uint32_t size);
 
#ifdef __cplusplus
}
#endif
 
#endif /* ZEPHYR_INCLUDE_SYS_RING_BUFFER_H_ */