diff options
Diffstat (limited to 'src/inputs/InputBuffered.cpp')
-rw-r--r-- | src/inputs/InputBuffered.cpp | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/src/inputs/InputBuffered.cpp b/src/inputs/InputBuffered.cpp new file mode 100644 index 0000000..9eea2a7 --- /dev/null +++ b/src/inputs/InputBuffered.cpp @@ -0,0 +1,131 @@ +/* + Copyright (C) 2009 Her Majesty the Queen in Right of Canada (Communications + Research Center Canada) + + Copyright (C) 2013 Matthias P. Braendli + http://mpb.li + + Base class for buffered inputs + + */ +/* + This file is part of CRC-DabMux. + + CRC-DabMux 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. + + CRC-DabMux 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 CRC-DabMux. If not, see <http://www.gnu.org/licenses/>. + */ + +#include "inputs/Input.h" + + +#include "TcpLog.h" + +#include <string> +#include <cstring> +#include <cstdlib> +#include <cstdio> +#include <fcntl.h> +#include <unistd.h> +#include <errno.h> + +#ifndef _WIN32 +# define O_BINARY 0 +#endif + +extern TcpLog etiLog; + +int InputBuffered::ReadFrame(void* buffer, int size) +{ + int retval = 0; + bool rc; + + switch (m_bufferstate) { + case PREBUFFERING: + rc = FillBuffer(); + if (rc) { + m_prebuffer_count--; + } + if (m_prebuffer_count == 0) { + etiLog.print(TcpLog::NOTICE, "input %s: pre-buffering complete\n", + GetName()); + m_bufferstate = RUNNING; + } + break; + + case RUNNING: + rc = FillBuffer(); + if (m_buffer.empty()) { + etiLog.print(TcpLog::WARNING, + "input %s input empty, re-enabling pre-buffering\n", + GetName()); + + // reinitialise prebuffering + m_bufferstate = PREBUFFERING; + m_prebuffer_count = m_prebuffer_stages; + } + else { + std::vector<char> &buffer_head = m_buffer.front(); + + memcpy(buffer, &buffer_head.front(), size); + etiLog.print(TcpLog::NOTICE, + "input %s got %d, %d\n", + GetName(), rc, m_buffer.size()); + + m_buffer.pop_front(); + retval = size; + } + break; + } + + // If we haven't filled buffer, return a nulled one + if (retval == 0) { + memset(buffer, 0, size); + retval = size; + } + + return retval; +} + +// This implemenation of FillBuffer assumes that +// input and output frames have same size. +// That's not the case with DAB+ superframes +bool InputBuffered::FillBuffer() +{ + if (m_buffer.size() > m_overfull_thresh) { + etiLog.print(TcpLog::WARNING, + "input %s buffer full, dropping frame !\n", + GetName()); + + // drop the surplus + int num_frames_to_drop = m_buffer.size() - m_overfull_thresh; + while (num_frames_to_drop--) + m_buffer.pop_front(); + + return true; + } + else { + // copy the input frame into the frame_buffer one to one + std::vector<char> frame(m_source_size); + int rc = ReadSource(&frame.front(), m_source_size); + if (rc == m_source_size) + { + m_buffer.push_back(frame); + return true; + } + else + { + return false; + } + } +} + |