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f71407ed2f
Developer errors are better represented with assert() rather than abort(). Also improve the strictness of the checks by using range checks within the assert() rather than converting the existing equality checks to inequality checks. Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Reviewed-by: Claudio Fontana <cfontana@suse.de> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20210121102518.20112-1-mark.cave-ayland@ilande.co.uk>
119 lines
2.6 KiB
C
119 lines
2.6 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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#include "qemu/osdep.h"
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#include "migration/vmstate.h"
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#include "qemu/fifo8.h"
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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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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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void fifo8_push(Fifo8 *fifo, uint8_t data)
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{
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assert(fifo->num < fifo->capacity);
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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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void fifo8_push_all(Fifo8 *fifo, const uint8_t *data, uint32_t num)
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{
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uint32_t start, avail;
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assert(fifo->num + num <= fifo->capacity);
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start = (fifo->head + fifo->num) % fifo->capacity;
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if (start + num <= fifo->capacity) {
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memcpy(&fifo->data[start], data, num);
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} else {
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avail = fifo->capacity - start;
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memcpy(&fifo->data[start], data, avail);
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memcpy(&fifo->data[0], &data[avail], num - avail);
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}
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fifo->num += num;
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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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assert(fifo->num > 0);
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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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const uint8_t *fifo8_pop_buf(Fifo8 *fifo, uint32_t max, uint32_t *num)
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{
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uint8_t *ret;
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assert(max > 0 && max <= fifo->num);
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*num = MIN(fifo->capacity - fifo->head, max);
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ret = &fifo->data[fifo->head];
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fifo->head += *num;
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fifo->head %= fifo->capacity;
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fifo->num -= *num;
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return ret;
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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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fifo->head = 0;
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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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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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uint32_t fifo8_num_free(Fifo8 *fifo)
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{
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return fifo->capacity - fifo->num;
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}
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uint32_t fifo8_num_used(Fifo8 *fifo)
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{
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return fifo->num;
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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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.fields = (VMStateField[]) {
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VMSTATE_VBUFFER_UINT32(data, Fifo8, 1, NULL, 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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