mirror of
https://github.com/DCC-EX/CommandStation-EX.git
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66 lines
1.6 KiB
C++
66 lines
1.6 KiB
C++
/*
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* © 2020, Chris Harlow. All rights reserved.
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*
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* This file is part of DCC-EX CommandStation-EX
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*
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* This is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* It is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with CommandStation. If not, see <https://www.gnu.org/licenses/>.
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*/
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#include "RingStream.h"
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#include "DIAG.h"
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RingStream::RingStream( const uint16_t len)
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{
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_len=len;
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_buffer=new byte[len];
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_pos_write=0;
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_pos_read=0;
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_buffer[0]=0;
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_overflow=false;
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}
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size_t RingStream::write(uint8_t byte) {
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if (_overflow) return 0;
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_buffer[_pos_write] = byte;
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++_pos_write;
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if (_pos_write>=_len) _pos_write=0;
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if (_pos_write==_pos_read) {
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_overflow=true;
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DIAG(F("\nRingStream(%d) OVERFLOW %d %d \n"),_len, _pos_write, _pos_read);
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return 0;
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}
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return 1;
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}
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int RingStream::read() {
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if (_pos_read==_pos_write) return -1;
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byte b=_buffer[_pos_read];
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_pos_read++;
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if (_pos_read>=_len) _pos_read=0;
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_overflow=false;
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return b;
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}
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int RingStream::count() {
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int peek=_pos_read;
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int counter=0;
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while(_buffer[peek]) {
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counter++;
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peek++;
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if (peek >= _len) peek=0;
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}
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return counter;
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}
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