| /* |
| * Generic FIFO component, implemented as a circular buffer. |
| * |
| * Copyright (c) 2012 Peter A. G. Crosthwaite |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "migration/vmstate.h" |
| #include "qemu/fifo8.h" |
| |
| void fifo8_create(Fifo8 *fifo, uint32_t capacity) |
| { |
| fifo->data = g_new(uint8_t, capacity); |
| fifo->capacity = capacity; |
| fifo->head = 0; |
| fifo->num = 0; |
| } |
| |
| void fifo8_destroy(Fifo8 *fifo) |
| { |
| g_free(fifo->data); |
| } |
| |
| void fifo8_push(Fifo8 *fifo, uint8_t data) |
| { |
| if (fifo->num == fifo->capacity) { |
| abort(); |
| } |
| fifo->data[(fifo->head + fifo->num) % fifo->capacity] = data; |
| fifo->num++; |
| } |
| |
| void fifo8_push_all(Fifo8 *fifo, const uint8_t *data, uint32_t num) |
| { |
| uint32_t start, avail; |
| |
| if (fifo->num + num > fifo->capacity) { |
| abort(); |
| } |
| |
| start = (fifo->head + fifo->num) % fifo->capacity; |
| |
| if (start + num <= fifo->capacity) { |
| memcpy(&fifo->data[start], data, num); |
| } else { |
| avail = fifo->capacity - start; |
| memcpy(&fifo->data[start], data, avail); |
| memcpy(&fifo->data[0], &data[avail], num - avail); |
| } |
| |
| fifo->num += num; |
| } |
| |
| uint8_t fifo8_pop(Fifo8 *fifo) |
| { |
| uint8_t ret; |
| |
| if (fifo->num == 0) { |
| abort(); |
| } |
| ret = fifo->data[fifo->head++]; |
| fifo->head %= fifo->capacity; |
| fifo->num--; |
| return ret; |
| } |
| |
| const uint8_t *fifo8_pop_buf(Fifo8 *fifo, uint32_t max, uint32_t *num) |
| { |
| uint8_t *ret; |
| |
| if (max == 0 || max > fifo->num) { |
| abort(); |
| } |
| *num = MIN(fifo->capacity - fifo->head, max); |
| ret = &fifo->data[fifo->head]; |
| fifo->head += *num; |
| fifo->head %= fifo->capacity; |
| fifo->num -= *num; |
| return ret; |
| } |
| |
| void fifo8_reset(Fifo8 *fifo) |
| { |
| fifo->num = 0; |
| fifo->head = 0; |
| } |
| |
| bool fifo8_is_empty(Fifo8 *fifo) |
| { |
| return (fifo->num == 0); |
| } |
| |
| bool fifo8_is_full(Fifo8 *fifo) |
| { |
| return (fifo->num == fifo->capacity); |
| } |
| |
| uint32_t fifo8_num_free(Fifo8 *fifo) |
| { |
| return fifo->capacity - fifo->num; |
| } |
| |
| uint32_t fifo8_num_used(Fifo8 *fifo) |
| { |
| return fifo->num; |
| } |
| |
| const VMStateDescription vmstate_fifo8 = { |
| .name = "Fifo8", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .fields = (VMStateField[]) { |
| VMSTATE_VBUFFER_UINT32(data, Fifo8, 1, NULL, capacity), |
| VMSTATE_UINT32(head, Fifo8), |
| VMSTATE_UINT32(num, Fifo8), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |