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#ifndef FIFO_H
#define FIFO_H
#include "migration/vmstate.h"
typedef struct {
/* All fields are private */
uint8_t *data;
uint32_t capacity;
uint32_t head;
uint32_t num;
} Fifo8;
/**
* fifo8_create:
* @fifo: struct Fifo8 to initialise with new FIFO
* @capacity: capacity of the newly created FIFO
*
* Create a FIFO of the specified size. Clients should call fifo8_destroy()
* when finished using the fifo. The FIFO is initially empty.
*/
void fifo8_create(Fifo8 *fifo, uint32_t capacity);
/**
* fifo8_destroy:
* @fifo: FIFO to cleanup
*
* Cleanup a FIFO created with fifo8_create(). Frees memory created for FIFO
*storage. The FIFO is no longer usable after this has been called.
*/
void fifo8_destroy(Fifo8 *fifo);
/**
* fifo8_push:
* @fifo: FIFO to push to
* @data: data byte to push
*
* Push a data byte to the FIFO. Behaviour is undefined if the FIFO is full.
* Clients are responsible for checking for fullness using fifo8_is_full().
*/
void fifo8_push(Fifo8 *fifo, uint8_t data);
/**
* fifo8_push_all:
* @fifo: FIFO to push to
* @data: data to push
* @size: number of bytes to push
*
* Push a byte array to the FIFO. Behaviour is undefined if the FIFO is full.
* Clients are responsible for checking the space left in the FIFO using
* fifo8_num_free().
*/
void fifo8_push_all(Fifo8 *fifo, const uint8_t *data, uint32_t num);
/**
* fifo8_pop:
* @fifo: fifo to pop from
*
* Pop a data byte from the FIFO. Behaviour is undefined if the FIFO is empty.
* Clients are responsible for checking for emptyness using fifo8_is_empty().
*
* Returns: The popped data byte.
*/
uint8_t fifo8_pop(Fifo8 *fifo);
/**
* fifo8_pop_buf:
* @fifo: FIFO to pop from
* @max: maximum number of bytes to pop
* @num: actual number of returned bytes
*
* Pop a number of elements from the FIFO up to a maximum of max. The buffer
* containing the popped data is returned. This buffer points directly into
* the FIFO backing store and data is invalidated once any of the fifo8_* APIs
* are called on the FIFO.
*
* The function may return fewer bytes than requested when the data wraps
* around in the ring buffer; in this case only a contiguous part of the data
* is returned.
*
* The number of valid bytes returned is populated in *num; will always return
* at least 1 byte. max must not be 0 or greater than the number of bytes in
* the FIFO.
*
* Clients are responsible for checking the availability of requested data
* using fifo8_num_used().
*
* Returns: A pointer to popped data.
*/
const uint8_t *fifo8_pop_buf(Fifo8 *fifo, uint32_t max, uint32_t *num);
/**
* fifo8_reset:
* @fifo: FIFO to reset
*
* Reset a FIFO. All data is discarded and the FIFO is emptied.
*/
void fifo8_reset(Fifo8 *fifo);
/**
* fifo8_is_empty:
* @fifo: FIFO to check
*
* Check if a FIFO is empty.
*
* Returns: True if the fifo is empty, false otherwise.
*/
bool fifo8_is_empty(Fifo8 *fifo);
/**
* fifo8_is_full:
* @fifo: FIFO to check
*
* Check if a FIFO is full.
*
* Returns: True if the fifo is full, false otherwise.
*/
bool fifo8_is_full(Fifo8 *fifo);
/**
* fifo8_num_free:
* @fifo: FIFO to check
*
* Return the number of free bytes in the FIFO.
*
* Returns: Number of free bytes.
*/
uint32_t fifo8_num_free(Fifo8 *fifo);
/**
* fifo8_num_used:
* @fifo: FIFO to check
*
* Return the number of used bytes in the FIFO.
*
* Returns: Number of used bytes.
*/
uint32_t fifo8_num_used(Fifo8 *fifo);
extern const VMStateDescription vmstate_fifo8;
#define VMSTATE_FIFO8(_field, _state) { \
.name = (stringify(_field)), \
.size = sizeof(Fifo8), \
.vmsd = &vmstate_fifo8, \
.flags = VMS_STRUCT, \
.offset = vmstate_offset_value(_state, _field, Fifo8), \
}
#endif /* FIFO_H */
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