80 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			80 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * Generic FIFO component, implemented as a circular buffer.
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|  *
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|  * Copyright (c) 2012 Peter A. G. Crosthwaite
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License
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|  * as published by the Free Software Foundation; either version
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|  * 2 of the License, or (at your option) any later version.
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|  *
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|  * You should have received a copy of the GNU General Public License along
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|  * with this program; if not, see <http://www.gnu.org/licenses/>.
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|  */
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| 
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| #include "qemu-common.h"
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| #include "qemu/fifo8.h"
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| 
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| void fifo8_create(Fifo8 *fifo, uint32_t capacity)
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| {
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|     fifo->data = g_new(uint8_t, capacity);
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|     fifo->capacity = capacity;
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|     fifo->head = 0;
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|     fifo->num = 0;
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| }
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| 
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| void fifo8_destroy(Fifo8 *fifo)
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| {
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|     g_free(fifo->data);
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| }
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| 
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| void fifo8_push(Fifo8 *fifo, uint8_t data)
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| {
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|     if (fifo->num == fifo->capacity) {
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|         abort();
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|     }
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|     fifo->data[(fifo->head + fifo->num) % fifo->capacity] = data;
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|     fifo->num++;
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| }
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| 
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| uint8_t fifo8_pop(Fifo8 *fifo)
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| {
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|     uint8_t ret;
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| 
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|     if (fifo->num == 0) {
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|         abort();
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|     }
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|     ret = fifo->data[fifo->head++];
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|     fifo->head %= fifo->capacity;
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|     fifo->num--;
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|     return ret;
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| }
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| 
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| void fifo8_reset(Fifo8 *fifo)
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| {
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|     fifo->num = 0;
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| }
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| 
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| bool fifo8_is_empty(Fifo8 *fifo)
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| {
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|     return (fifo->num == 0);
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| }
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| 
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| bool fifo8_is_full(Fifo8 *fifo)
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| {
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|     return (fifo->num == fifo->capacity);
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| }
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| 
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| const VMStateDescription vmstate_fifo8 = {
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|     .name = "Fifo8",
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|     .version_id = 1,
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|     .minimum_version_id = 1,
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|     .minimum_version_id_old = 1,
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|     .fields      = (VMStateField[]) {
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|         VMSTATE_VBUFFER_UINT32(data, Fifo8, 1, NULL, 0, capacity),
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|         VMSTATE_UINT32(head, Fifo8),
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|         VMSTATE_UINT32(num, Fifo8),
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|         VMSTATE_END_OF_LIST()
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|     }
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| };
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