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** Copyright (C) 2016 The Qt Company Ltd.
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#include "sshremoteprocess.h"

#include "sshlogging_p.h"
#include "sshsettings.h"

#include <utils/fileutils.h>
#include <utils/qtcassert.h>

#include <QTimer>

#include <cstring>
#include <cstdlib>

/*!
    \class QSsh::SshRemoteProcess

    \brief The SshRemoteProcess class implements an SSH channel for running a
    remote process.

    Objects are created via SshConnection::createRemoteProcess.
    The process is started via the start() member function.
    If the process needs a pseudo terminal, you can request one
    via requestTerminal() before calling start().
 */

namespace QSsh {
using namespace Internal;

struct SshRemoteProcess::SshRemoteProcessPrivate
{
    QByteArray remoteCommand;
    QStringList connectionArgs;
    QString displayName;
    bool useTerminal = false;
};

SshRemoteProcess::SshRemoteProcess(const QByteArray &command, const QStringList &connectionArgs)
    : d(new SshRemoteProcessPrivate)
{
    d->remoteCommand = command;
    d->connectionArgs = connectionArgs;

    connect(this,
            static_cast<void (QProcess::*)(int, QProcess::ExitStatus)>(&QProcess::finished),
            [this] {
        QString error;
        if (exitStatus() == QProcess::CrashExit)
            error = tr("The ssh binary crashed: %1").arg(errorString());
        else if (exitCode() == 255)
            error = tr("Remote process crashed.");
        emit done(error);
    });
    connect(this, &QProcess::errorOccurred, [this](QProcess::ProcessError error) {
        if (error == QProcess::FailedToStart)
            emit done(errorString());
    });
}

void SshRemoteProcess::doStart()
{
    QTC_ASSERT(!isRunning(), return);
    QStringList args = QStringList("-q") << d->connectionArgs;
    if (d->useTerminal)
        args.prepend("-tt");
    if (!d->displayName.isEmpty()) {
        args.prepend("-X");
        QProcessEnvironment env = processEnvironment();
        env.insert("DISPLAY", d->displayName);
        setProcessEnvironment(env);
    }
    if (!d->remoteCommand.isEmpty())
        args << QLatin1String(d->remoteCommand);
    qCDebug(sshLog) << "starting remote process:" << SshSettings::sshFilePath().toUserOutput()
                    << args;
    QProcess::start(SshSettings::sshFilePath().toString(), args);
}

SshRemoteProcess::~SshRemoteProcess()
{
    delete d;
}

void SshRemoteProcess::requestTerminal()
{
    d->useTerminal = true;
}

void SshRemoteProcess::requestX11Forwarding(const QString &displayName)
{
    d->displayName = displayName;
}

void SshRemoteProcess::start()
{
    QTimer::singleShot(0, this, &SshRemoteProcess::doStart);
}

bool SshRemoteProcess::isRunning() const
{
    return state() == QProcess::Running;
}

} // namespace QSsh