qemu-e2k/hw/fifo.h
Peter A. G. Crosthwaite a3578d4a51 hw: Added generic FIFO API.
Added a FIFO API that can be used to create and operate byte FIFOs.

Signed-off-by: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
2012-10-10 11:13:32 +10:00

100 lines
2.2 KiB
C

#ifndef FIFO_H
#define FIFO_H
#include "hw.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_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_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);
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 */