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/*-
* BSD 2-Clause License
*
* Copyright (c) 2012-2018, Jan Breuer
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "fifo_private.h"
/**
* Initialize fifo
* @param fifo
*/
void fifo_init(scpi_fifo_t * fifo, scpi_error_t * data, int16_t size) {
fifo->wr = 0;
fifo->rd = 0;
fifo->count = 0;
fifo->data = data;
fifo->size = size;
}
/**
* Empty fifo
* @param fifo
*/
void fifo_clear(scpi_fifo_t * fifo) {
fifo->wr = 0;
fifo->rd = 0;
fifo->count = 0;
}
/**
* Test if fifo is empty
* @param fifo
* @return
*/
scpi_bool_t fifo_is_empty(scpi_fifo_t * fifo) {
return fifo->count == 0;
}
/**
* Test if fifo is full
* @param fifo
* @return
*/
scpi_bool_t fifo_is_full(scpi_fifo_t * fifo) {
return fifo->count == fifo->size;
}
/**
* Add element to fifo. If fifo is full, return FALSE.
* @param fifo
* @param err
* @param info
* @return
*/
scpi_bool_t fifo_add(scpi_fifo_t * fifo, const scpi_error_t * value) {
/* FIFO full? */
if (fifo_is_full(fifo)) {
return FALSE;
}
if (!value) {
return FALSE;
}
fifo->data[fifo->wr] = *value;
fifo->wr = (fifo->wr + 1) % (fifo->size);
fifo->count += 1;
return TRUE;
}
/**
* Remove element form fifo
* @param fifo
* @param value
* @return FALSE - fifo is empty
*/
scpi_bool_t fifo_remove(scpi_fifo_t * fifo, scpi_error_t * value) {
/* FIFO empty? */
if (fifo_is_empty(fifo)) {
return FALSE;
}
if (value) {
*value = fifo->data[fifo->rd];
}
fifo->rd = (fifo->rd + 1) % (fifo->size);
fifo->count -= 1;
return TRUE;
}
/**
* Remove last element from fifo
* @param fifo
* @param value
* @return FALSE - fifo is empty
*/
scpi_bool_t fifo_remove_last(scpi_fifo_t * fifo, scpi_error_t * value) {
/* FIFO empty? */
if (fifo_is_empty(fifo)) {
return FALSE;
}
fifo->wr = (fifo->wr + fifo->size - 1) % (fifo->size);
if (value) {
*value = fifo->data[fifo->wr];
}
fifo->count -= 1;
return TRUE;
}
/**
* Retrive number of elements in fifo
* @param fifo
* @param value
* @return
*/
scpi_bool_t fifo_count(scpi_fifo_t * fifo, int16_t * value) {
*value = fifo->count;
return TRUE;
}