mirror of
https://github.com/qmk/qmk_firmware.git
synced 2024-11-25 12:46:41 +00:00
65 lines
2.3 KiB
C
65 lines
2.3 KiB
C
// this is a single reader [maybe multiple writer?] byte queue
|
|
// Copyright 2008 Alex Norman
|
|
// writen by Alex Norman
|
|
//
|
|
// This file is part of avr-bytequeue.
|
|
//
|
|
// avr-bytequeue 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 3 of the License, or
|
|
//(at your option) any later version.
|
|
//
|
|
// avr-bytequeue 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 avr-bytequeue. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
#include "bytequeue.h"
|
|
#include "interrupt_setting.h"
|
|
|
|
void bytequeue_init(byteQueue_t* queue, uint8_t* dataArray, byteQueueIndex_t arrayLen) {
|
|
queue->length = arrayLen;
|
|
queue->data = dataArray;
|
|
queue->start = queue->end = 0;
|
|
}
|
|
|
|
bool bytequeue_enqueue(byteQueue_t* queue, uint8_t item) {
|
|
interrupt_setting_t setting = store_and_clear_interrupt();
|
|
// full
|
|
if (((queue->end + 1) % queue->length) == queue->start) {
|
|
restore_interrupt_setting(setting);
|
|
return false;
|
|
} else {
|
|
queue->data[queue->end] = item;
|
|
queue->end = (queue->end + 1) % queue->length;
|
|
restore_interrupt_setting(setting);
|
|
return true;
|
|
}
|
|
}
|
|
|
|
byteQueueIndex_t bytequeue_length(byteQueue_t* queue) {
|
|
byteQueueIndex_t len;
|
|
interrupt_setting_t setting = store_and_clear_interrupt();
|
|
if (queue->end >= queue->start)
|
|
len = queue->end - queue->start;
|
|
else
|
|
len = (queue->length - queue->start) + queue->end;
|
|
restore_interrupt_setting(setting);
|
|
return len;
|
|
}
|
|
|
|
// we don't need to avoid interrupts if there is only one reader
|
|
uint8_t bytequeue_get(byteQueue_t* queue, byteQueueIndex_t index) {
|
|
return queue->data[(queue->start + index) % queue->length];
|
|
}
|
|
|
|
// we just update the start index to remove elements
|
|
void bytequeue_remove(byteQueue_t* queue, byteQueueIndex_t numToRemove) {
|
|
interrupt_setting_t setting = store_and_clear_interrupt();
|
|
queue->start = (queue->start + numToRemove) % queue->length;
|
|
restore_interrupt_setting(setting);
|
|
}
|