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/*
* Ring buffer helpers
*
* Copyright (c) 2020 Michael Buesch <m@bues.ch>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "compat.h"
#include "ring.h"
uint8_t ring_next(uint8_t current, uint8_t max_index)
{
uint8_t next;
next = (uint8_t)(current + 1u);
if (next > max_index)
next = 0u;
return next;
}
uint8_t ring_prev(uint8_t current, uint8_t max_index)
{
uint8_t prev;
prev = (uint8_t)(current - 1u);
if (prev > max_index)
prev = max_index;
return prev;
}
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