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/**
* @brief simple circular buffer
*/
#ifndef _RING_BUFFER_H_
#define _RING_BUFFER_H_
#ifdef __cplusplus
extern "C"{
#endif
/* The buffer is empty when head == tail.
* The buffer is full when the head is one byte in front of the tail
* The total buffer size must be a power of two
* One byte is left free to distinguish empty from full */
typedef struct ring_buffer {
uint32 head;
uint32 tail;
uint8 size;
uint8 *buf;
} ring_buffer;
static inline void rb_init(ring_buffer *rb, uint8 size, uint8 *buf) {
ASSERT(IS_POWER_OF_TWO(size));
rb->head = 0;
rb->tail = 0;
rb->size = size;
rb->buf = buf;
}
static inline void rb_insert(ring_buffer *rb, uint8 element) {
rb->buf[(rb->tail)++] = element;
rb->tail &= (rb->size - 1);
}
static inline uint8 rb_remove(ring_buffer *rb) {
uint8 ch = rb->buf[rb->head++];
rb->head &= (rb->size - 1);
return ch;
}
static inline uint32 rb_full_count(ring_buffer *rb) {
return rb->tail - rb->head;
}
static inline void rb_reset(ring_buffer *rb) {
rb->tail = rb->head;
}
#ifdef __cplusplus
} // extern "C"
#endif
#endif
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