portapack-mayhem/firmware/baseband/stream_output.cpp
2017-01-10 19:45:40 +00:00

77 lines
2.4 KiB
C++

/*
* Copyright (C) 2016 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2016 Furrtek
*
* This file is part of PortaPack.
*
* 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, 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; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#include "stream_output.hpp"
#include "lpc43xx_cpp.hpp"
using namespace lpc43xx;
StreamOutput::StreamOutput(ReplayConfig* const config) :
fifo_buffers_empty { buffers_empty.data(), buffer_count_max_log2 },
fifo_buffers_full { buffers_full.data(), buffer_count_max_log2 },
config { config },
data { std::make_unique<uint8_t[]>(config->read_size * config->buffer_count) }
{
config->fifo_buffers_empty = &fifo_buffers_empty;
config->fifo_buffers_full = &fifo_buffers_full;
for(size_t i=0; i<config->buffer_count; i++) {
buffers[i] = { &(data.get()[i * config->read_size]), config->read_size };
fifo_buffers_empty.in(&buffers[i]);
}
}
size_t StreamOutput::write(const void* const data, const size_t length) {
const uint8_t* p = static_cast<const uint8_t*>(data);
size_t written = 0;
while( written < length ) {
if( !active_buffer ) {
// We need an empty buffer...
if( !fifo_buffers_empty.out(active_buffer) ) {
// ...but none are available. Samples were dropped.
break;
}
}
const auto remaining = length - written;
written += active_buffer->write(&p[written], remaining);
if( active_buffer->is_full() ) {
if( !fifo_buffers_full.in(active_buffer) ) {
// FIFO is fuil of buffers, there's no place for this one.
// Bail out of the loop, and try submitting the buffer in the
// next pass.
// This should never happen if the number of buffers is less
// than the capacity of the FIFO.
break;
}
active_buffer = nullptr;
creg::m4txevent::assert();
}
}
config->baseband_bytes_sent += length;
return written;
}