mosesdecoder/phrase-extract/OutputFileStream.h
Jeroen Vermeulen ea9b097aba OutputFileStream: accept ‘-’ for “stdout”.
This is a common convention: when a program gets a dash as the path of a
file that it should write, it writes to standard output instead.

Enhances portability to systems that don't have /dev/stdout.
2015-05-26 15:06:04 +07:00

82 lines
2.6 KiB
C++

// $Id: InputFileStream.h 2939 2010-02-24 11:15:44Z jfouet $
/***********************************************************************
Moses - factored phrase-based language decoder
Copyright (C) 2006 University of Edinburgh
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
***********************************************************************/
#pragma once
#include <cstdlib>
#include <fstream>
#include <string>
#include <iostream>
#include <boost/iostreams/filtering_stream.hpp>
namespace Moses
{
/** Version of std::ostream with transparent compression.
*
* Transparently compresses output when writing to a file whose name ends in
* ".gz". Or, writes to stdout instead of a file when given a filename
* consisting of just a dash ("-").
*/
class OutputFileStream : public boost::iostreams::filtering_ostream
{
private:
/** File that needs flushing & closing when we close this stream.
*
* Is NULL when no file is opened, e.g. when writing to standard output.
*/
std::ofstream *m_outFile;
/// Is this stream open?
bool m_open;
public:
/** Create an unopened OutputFileStream.
*
* Until it's been opened, nothing can be done with this stream.
*/
OutputFileStream();
/// Create an OutputFileStream, and open it by calling Open().
OutputFileStream(const std::string &filePath);
virtual ~OutputFileStream();
// TODO: Can we please just always throw an exception when this fails?
/** Open stream.
*
* If filePath is "-" (just a dash), this opens the stream for writing to
* standard output. Otherwise, it opens the given file. If the filename
* has the ".gz" suffix, output will be transparently compressed.
*
* Call Close() to close the file.
*
* Returns whether opening the file was successful. It may also throw an
* exception on failure.
*/
bool Open(const std::string &filePath);
/// Flush and close stream. After this, the stream can be opened again.
void Close();
};
}