src/DLVProcess.cpp

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/* dlvhex -- Answer-Set Programming with external interfaces.
 * Copyright (C) 2005-2007 Roman Schindlauer
 * Copyright (C) 2006-2015 Thomas Krennwallner
 * Copyright (C) 2009-2016 Peter Schüller
 * Copyright (C) 2011-2016 Christoph Redl
 * Copyright (C) 2015-2016 Tobias Kaminski
 * Copyright (C) 2015-2016 Antonius Weinzierl
 *
 * This file is part of dlvhex.
 *
 * dlvhex 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.
 *
 * dlvhex 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 dlvhex; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif                           // HAVE_CONFIG_H

#include "dlvhex2/DLVProcess.h"
#include "dlvhex2/Logger.h"

#include <iostream>
#include <boost/iostreams/tee.hpp>
#include <boost/iostreams/filtering_stream.hpp>

DLVHEX_NAMESPACE_BEGIN

DLVProcess::DLVProcess()
: proc(), ipipe(0), opipe(0), executable(), argv()
{ }

DLVProcess::~DLVProcess()
{
    proc.close();
    delete opipe;
    delete ipipe;
}


void
DLVProcess::addOption(const std::string& option)
{
    argv.push_back(option);
}


void
DLVProcess::setPath(const std::string& path)
{
    executable = path;
}


std::string
DLVProcess::path() const
{
    return executable;
}


std::vector<std::string>
DLVProcess::commandline() const
{
    std::vector<std::string> tmp;

    assert(!path().empty());
    tmp.push_back(path());
    tmp.insert(tmp.end(), argv.begin(), argv.end());

    return tmp;
}


void
DLVProcess::setupStreams()
{
    if (ipipe == 0 && opipe == 0) {
        #ifndef NDEBUG
        if( Logger::Instance().shallPrint(Logger::DBG) ) {
            // setup iostreams to copy to log stream
            DBGLOG(DBG,"Setting up DLVProcess opipe to be verbose");

            boost::iostreams::filtering_ostream* tmpopipe = new boost::iostreams::filtering_ostream;

            tmpopipe->push(boost::iostreams::tee_filter<std::streambuf>(proc));
            tmpopipe->push(Logger::Instance().stream());

            opipe = tmpopipe;
        }
        else
        #endif
        {
            opipe = new std::iostream(&proc);
        }

        ipipe = new std::iostream(&proc);

        // let ProcessBuf throw std::ios_base::failure
        opipe->exceptions(std::ios_base::badbit);
        ipipe->exceptions(std::ios_base::badbit);
    }
}


void
DLVProcess::spawn()
{
    setupStreams();
    proc.open(commandline());
}


void
DLVProcess::spawn(const std::vector<std::string>& opt)
{
    setupStreams();
    std::vector<std::string> tmp(opt);
    assert(!path().empty());
    tmp.insert(tmp.begin(), path());
    proc.open(tmp);
}


void
DLVProcess::endoffile()
{
    proc.endoffile();
}


int
DLVProcess::close(bool kill)
{
    assert(ipipe != 0 && opipe != 0);

    // first reset the state of the iostreams in order to re-use them
    opipe->clear();
    ipipe->clear();
    // exit code of process
    return proc.close(kill);
}


std::ostream&
DLVProcess::getOutput()
{
    assert(opipe != 0);
    return *opipe;
}


std::istream&
DLVProcess::getInput()
{
    assert(ipipe != 0);
    return *ipipe;
}


DLVHEX_NAMESPACE_END


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