gdbengine.cpp

/**************************************************************************
**
** This file is part of Qt Creator
**
** Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
**
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** Commercial Usage
**
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
**
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://qt.nokia.com/contact.
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#define QT_NO_CAST_FROM_ASCII

#include "gdbengine.h"

#include "gdboptionspage.h"
#include "debuggeruiswitcher.h"
#include "debuggermainwindow.h"
#include "debuggerplugin.h"

#include "attachgdbadapter.h"
#include "coregdbadapter.h"
#include "localplaingdbadapter.h"
#include "termgdbadapter.h"
#include "remotegdbserveradapter.h"
#include "remoteplaingdbadapter.h"
#include "trkgdbadapter.h"

#include "watchutils.h"
#include "debuggeractions.h"
#include "debuggeragents.h"
#include "debuggerconstants.h"
#include "debuggertooltip.h"
#include "debuggerstringutils.h"
#include "gdbmi.h"

#include "breakhandler.h"
#include "moduleshandler.h"
#include "registerhandler.h"
#include "snapshothandler.h"
#include "sourcefileshandler.h"
#include "stackhandler.h"
#include "threadshandler.h"
#include "watchhandler.h"

#include "sourcefileswindow.h"

#include "debuggerdialogs.h"

#include <utils/qtcassert.h>
#include <utils/fancymainwindow.h>
#include <texteditor/itexteditor.h>
#include <projectexplorer/toolchain.h>
#include <coreplugin/icore.h>
#include <coreplugin/progressmanager/progressmanager.h>
#include <coreplugin/progressmanager/futureprogress.h>

#include <QtCore/QCoreApplication>
#include <QtCore/QDebug>
#include <QtCore/QDir>
#include <QtCore/QFileInfo>
#include <QtCore/QMetaObject>
#include <QtCore/QTime>
#include <QtCore/QTimer>
#include <QtCore/QTemporaryFile>
#include <QtCore/QTextStream>

#include <QtGui/QAction>
#include <QtGui/QDialogButtonBox>
#include <QtGui/QLabel>
#include <QtGui/QMainWindow>
#include <QtGui/QMessageBox>
#include <QtGui/QPushButton>

#ifdef Q_OS_UNIX
#include <unistd.h>
#include <dlfcn.h>
#endif
#include <ctype.h>


namespace Debugger {
namespace Internal {

//#define DEBUG_PENDING  1

static const char winPythonVersionC[] = "python2.5";

#if DEBUG_PENDING
#   define PENDING_DEBUG(s) qDebug() << s
#else
#   define PENDING_DEBUG(s)
#endif
#define PENDING_DEBUGX(s) qDebug() << s

#define CB(callback) &GdbEngine::callback, STRINGIFY(callback)

QByteArray GdbEngine::tooltipINameForExpression(const QByteArray &exp)
{
    // FIXME: 'exp' can contain illegal characters
    //return "tooltip." + exp;
    Q_UNUSED(exp)
    return "tooltip.x";
}

static bool stateAcceptsGdbCommands(DebuggerState state)
{
    switch (state) {
    case AdapterStarting:
    case AdapterStarted:
    case AdapterStartFailed:
    case InferiorUnrunnable:
    case InferiorStarting:
    case InferiorStartFailed:
    case InferiorRunningRequested:
    case InferiorRunningRequested_Kill:
    case InferiorRunning:
    case InferiorStopping:
    case InferiorStopping_Kill:
    case InferiorStopped:
    case InferiorShuttingDown:
    case InferiorShutDown:
    case InferiorShutdownFailed:
        return true;
    case DebuggerNotReady:
    case EngineStarting:
    case InferiorStopFailed:
    case EngineShuttingDown:
        break;
    }
    return false;
}

static int &currentToken()
{
    static int token = 0;
    return token;
}

static QByteArray parsePlainConsoleStream(const GdbResponse &response)
{
    GdbMi output = response.data.findChild("consolestreamoutput");
    QByteArray out = output.data();
    // FIXME: proper decoding needed
    if (out.endsWith("\\n"))
        out.chop(2);
    while (out.endsWith('\n') || out.endsWith(' '))
        out.chop(1);
    int pos = out.indexOf(" = ");
    return out.mid(pos + 3);
}

///////////////////////////////////////////////////////////////////////
//
// GdbEngine
//
///////////////////////////////////////////////////////////////////////

GdbEngine::GdbEngine(const DebuggerStartParameters &startParameters)
  : DebuggerEngine(startParameters)
{
    m_gdbAdapter = 0;
    m_progress = 0;

    m_commandTimer = new QTimer(this);
    m_commandTimer->setSingleShot(true);
    connect(m_commandTimer, SIGNAL(timeout()), SLOT(commandTimeout()));

    // Needs no resetting in initializeVariables()
    m_busy = false;
    initializeVariables();

    connect(theDebuggerAction(AutoDerefPointers), SIGNAL(valueChanged(QVariant)),
            this, SLOT(setAutoDerefPointers(QVariant)));
    connect(theDebuggerAction(CreateFullBacktrace), SIGNAL(triggered()),
            this, SLOT(createFullBacktrace()));
}

void GdbEngine::connectDebuggingHelperActions()
{
    connect(theDebuggerAction(UseDebuggingHelpers), SIGNAL(valueChanged(QVariant)),
            this, SLOT(setUseDebuggingHelpers(QVariant)));
    connect(theDebuggerAction(DebugDebuggingHelpers), SIGNAL(valueChanged(QVariant)),
            this, SLOT(setDebugDebuggingHelpersClassic(QVariant)));
    connect(theDebuggerAction(RecheckDebuggingHelpers), SIGNAL(triggered()),
            this, SLOT(recheckDebuggingHelperAvailabilityClassic()));
}

void GdbEngine::disconnectDebuggingHelperActions()
{
    disconnect(theDebuggerAction(UseDebuggingHelpers), 0, this, 0);
    disconnect(theDebuggerAction(DebugDebuggingHelpers), 0, this, 0);
    disconnect(theDebuggerAction(RecheckDebuggingHelpers), 0, this, 0);
}

DebuggerStartMode GdbEngine::startMode() const
{
    return startParameters().startMode;
}

QMainWindow *GdbEngine::mainWindow() const
{
    return DebuggerUISwitcher::instance()->mainWindow();
}

AbstractGdbProcess *GdbEngine::gdbProc() const
{
    return m_gdbAdapter->gdbProc();
}

GdbEngine::~GdbEngine()
{
    // Prevent sending error messages afterwards.
    if (m_gdbAdapter)
        disconnect(gdbProc(), 0, this, 0);
    delete m_gdbAdapter;
    m_gdbAdapter = 0;
}

void GdbEngine::connectAdapter()
{
    connect(m_gdbAdapter, SIGNAL(adapterStarted()),
        this, SLOT(handleAdapterStarted()));
    connect(m_gdbAdapter, SIGNAL(adapterStartFailed(QString,QString)),
        this, SLOT(handleAdapterStartFailed(QString,QString)));
    connect(m_gdbAdapter, SIGNAL(inferiorPrepared()),
        this, SLOT(handleInferiorPrepared()));
    connect(m_gdbAdapter, SIGNAL(inferiorStartFailed(QString)),
        this, SLOT(handleInferiorStartFailed(QString)));
    connect(m_gdbAdapter, SIGNAL(adapterCrashed(QString)),
        this, SLOT(handleAdapterCrashed(QString)));
}

void GdbEngine::initializeVariables()
{
    m_debuggingHelperState = DebuggingHelperUninitialized;
    m_gdbVersion = 100;
    m_gdbBuildVersion = -1;
    m_isMacGdb = false;
    m_hasPython = false;
    m_registerNamesListed = false;

    m_fullToShortName.clear();
    m_shortToFullName.clear();

    invalidateSourcesList();
    m_sourcesListUpdating = false;
    m_oldestAcceptableToken = -1;
    m_outputCodec = QTextCodec::codecForLocale();
    m_pendingWatchRequests = 0;
    m_pendingBreakpointRequests = 0;
    m_commandsDoneCallback = 0;
    m_commandsToRunOnTemporaryBreak.clear();
    m_cookieForToken.clear();

    m_pendingConsoleStreamOutput.clear();
    m_pendingLogStreamOutput.clear();

    m_inbuffer.clear();
    m_resultVarName.clear();

    m_commandTimer->stop();

    // ConverterState has no reset() function.
    m_outputCodecState.~ConverterState();
    new (&m_outputCodecState) QTextCodec::ConverterState();

    m_currentFunctionArgs.clear();
    m_currentFrame.clear();
    m_dumperHelper.clear();
#ifdef Q_OS_LINUX
    m_entryPoint.clear();
#endif
    delete m_progress;
    m_progress = 0;
}

QString GdbEngine::errorMessage(QProcess::ProcessError error)
{
    switch (error) {
        case QProcess::FailedToStart:
            return tr("The Gdb process failed to start. Either the "
                "invoked program '%1' is missing, or you may have insufficient "
                "permissions to invoke the program.")
                .arg(m_gdb);
        case QProcess::Crashed:
            return tr("The Gdb process crashed some time after starting "
                "successfully.");
        case QProcess::Timedout:
            return tr("The last waitFor...() function timed out. "
                "The state of QProcess is unchanged, and you can try calling "
                "waitFor...() again.");
        case QProcess::WriteError:
            return tr("An error occurred when attempting to write "
                "to the Gdb process. For example, the process may not be running, "
                "or it may have closed its input channel.");
        case QProcess::ReadError:
            return tr("An error occurred when attempting to read from "
                "the Gdb process. For example, the process may not be running.");
        default:
            return tr("An unknown error in the Gdb process occurred. ");
    }
}

#if 0
static void dump(const char *first, const char *middle, const QString & to)
{
    QByteArray ba(first, middle - first);
    Q_UNUSED(to)
    // note that qDebug cuts off output after a certain size... (bug?)
    qDebug("\n>>>>> %s\n%s\n====\n%s\n<<<<<\n",
        qPrintable(currentTime()),
        qPrintable(QString(ba).trimmed()),
        qPrintable(to.trimmed()));
    //qDebug() << "";
    //qDebug() << qPrintable(currentTime())
    //    << " Reading response:  " << QString(ba).trimmed() << "\n";
}
#endif

void GdbEngine::readDebugeeOutput(const QByteArray &data)
{
    QString msg = m_outputCodec->toUnicode(data.constData(), data.length(),
        &m_outputCodecState);
    showMessage(msg, AppStuff);
}

void GdbEngine::handleResponse(const QByteArray &buff)
{
    static QTime lastTime;

    if (theDebuggerBoolSetting(LogTimeStamps))
        showMessage(currentTime(), LogTime);
    showMessage(QString::fromLocal8Bit(buff, buff.length()), LogOutput);

#if 0
    qDebug() // << "#### start response handling #### "
        << currentTime()
        << lastTime.msecsTo(QTime::currentTime()) << "ms,"
        << "buf:" << buff.left(1500) << "..."
        //<< "buf:" << buff
        << "size:" << buff.size();
#else
    //qDebug() << "buf:" << buff;
#endif

    lastTime = QTime::currentTime();

    if (buff.isEmpty() || buff == "(gdb) ")
        return;

    const char *from = buff.constData();
    const char *to = from + buff.size();
    const char *inner;

    int token = -1;
    // token is a sequence of numbers
    for (inner = from; inner != to; ++inner)
        if (*inner < '0' || *inner > '9')
            break;
    if (from != inner) {
        token = QByteArray(from, inner - from).toInt();
        from = inner;
        //qDebug() << "found token" << token;
    }

    // next char decides kind of response
    const char c = *from++;
    //qDebug() << "CODE:" << c;
    switch (c) {
        case '*':
        case '+':
        case '=': {
            QByteArray asyncClass;
            for (; from != to; ++from) {
                const char c = *from;
                if (!isNameChar(c))
                    break;
                asyncClass += *from;
            }
            //qDebug() << "ASYNCCLASS" << asyncClass;

            GdbMi result;
            while (from != to) {
                GdbMi data;
                if (*from != ',') {
                    // happens on archer where we get
                    // 23^running <NL> *running,thread-id="all" <NL> (gdb)
                    result.m_type = GdbMi::Tuple;
                    break;
                }
                ++from; // skip ','
                data.parseResultOrValue(from, to);
                if (data.isValid()) {
                    //qDebug() << "parsed result:" << data.toString();
                    result.m_children += data;
                    result.m_type = GdbMi::Tuple;
                }
            }
            if (asyncClass == "stopped") {
                handleStopResponse(result);
                m_pendingLogStreamOutput.clear();
                m_pendingConsoleStreamOutput.clear();
            } else if (asyncClass == "running") {
                // Archer has 'thread-id="all"' here
            } else if (asyncClass == "library-loaded") {
                // Archer has 'id="/usr/lib/libdrm.so.2",
                // target-name="/usr/lib/libdrm.so.2",
                // host-name="/usr/lib/libdrm.so.2",
                // symbols-loaded="0"
                QByteArray id = result.findChild("id").data();
                if (!id.isEmpty())
                    showStatusMessage(tr("Library %1 loaded").arg(_(id)), 1000);
                int progress = m_progress->progressValue();
                m_progress->setProgressValue(qMin(70, progress + 1));
                invalidateSourcesList();
            } else if (asyncClass == "library-unloaded") {
                // Archer has 'id="/usr/lib/libdrm.so.2",
                // target-name="/usr/lib/libdrm.so.2",
                // host-name="/usr/lib/libdrm.so.2"
                QByteArray id = result.findChild("id").data();
                showStatusMessage(tr("Library %1 unloaded").arg(_(id)), 1000);
                invalidateSourcesList();
            } else if (asyncClass == "thread-group-added") {
                // 7.1-symbianelf has "{id="i1"}"
            } else if (asyncClass == "thread-group-created"
                    || asyncClass == "thread-group-started") {
                // Archer had only "{id="28902"}" at some point of 6.8.x.
                // *-started seems to be standard in 7.1, but in early
                // 7.0.x, there was a *-created instead.
                const int progress = m_progress->progressValue();
                m_progress->setProgressValue(qMin(70, progress + 1));
                QByteArray id = result.findChild("id").data();
                showStatusMessage(tr("Thread group %1 created").arg(_(id)), 1000);
                const int pid = id.toInt();
                notifyInferiorPid(pid);
            } else if (asyncClass == "thread-created") {
                //"{id="1",group-id="28902"}"
                QByteArray id = result.findChild("id").data();
                showStatusMessage(tr("Thread %1 created").arg(_(id)), 1000);
            } else if (asyncClass == "thread-group-exited") {
                // Archer has "{id="28902"}"
                QByteArray id = result.findChild("id").data();
                showStatusMessage(tr("Thread group %1 exited").arg(_(id)), 1000);
            } else if (asyncClass == "thread-exited") {
                //"{id="1",group-id="28902"}"
                QByteArray id = result.findChild("id").data();
                QByteArray groupid = result.findChild("group-id").data();
                showStatusMessage(tr("Thread %1 in group %2 exited")
                    .arg(_(id)).arg(_(groupid)), 1000);
            } else if (asyncClass == "thread-selected") {
                QByteArray id = result.findChild("id").data();
                showStatusMessage(tr("Thread %1 selected").arg(_(id)), 1000);
                //"{id="2"}"
            } else if (m_isMacGdb && asyncClass == "shlibs-updated") {
                // Apple's gdb announces updated libs.
                invalidateSourcesList();
            } else if (m_isMacGdb && asyncClass == "shlibs-added") {
                // Apple's gdb announces added libs.
                // {shlib-info={num="2", name="libmathCommon.A_debug.dylib",
                // kind="-", dyld-addr="0x7f000", reason="dyld", requested-state="Y",
                // state="Y", path="/usr/lib/system/libmathCommon.A_debug.dylib",
                // description="/usr/lib/system/libmathCommon.A_debug.dylib",
                // loaded_addr="0x7f000", slide="0x7f000", prefix=""}}
                invalidateSourcesList();
            } else if (m_isMacGdb && asyncClass == "resolve-pending-breakpoint") {
                // Apple's gdb announces resolved breakpoints.
                // new_bp="1",pended_bp="1",new_expr="\"gdbengine.cpp\":1584",
                // bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
                // addr="0x0000000115cc3ddf",func="foo()",file="../foo.cpp",
                // line="1584",shlib="/../libFoo_debug.dylib",times="0"}
                const GdbMi bkpt = result.findChild("bkpt");
                const int number = bkpt.findChild("number").data().toInt();
                BreakpointData *data = breakHandler()->findBreakpointByNumber(number);
                setBreakpointDataFromOutput(data, bkpt);
                breakHandler()->updateMarkers();
            } else {
                qDebug() << "IGNORED ASYNC OUTPUT"
                    << asyncClass << result.toString();
            }
            break;
        }

        case '~': {
            QByteArray data = GdbMi::parseCString(from, to);
            m_pendingConsoleStreamOutput += data;

            // Parse pid from noise.
            if (!inferiorPid()) {
                // Linux/Mac gdb: [New [Tt]hread 0x545 (LWP 4554)]
                static QRegExp re1(_("New .hread 0x[0-9a-f]+ \\(LWP ([0-9]*)\\)"));
                // MinGW 6.8: [New thread 2437.0x435345]
                static QRegExp re2(_("New .hread ([0-9]+)\\.0x[0-9a-f]*"));
                // Mac: [Switching to process 9294 local thread 0x2e03] or
                // [Switching to process 31773]
                static QRegExp re3(_("Switching to process ([0-9]+)"));
                QTC_ASSERT(re1.isValid() && re2.isValid(), return);
                if (re1.indexIn(_(data)) != -1)
                    maybeHandleInferiorPidChanged(re1.cap(1));
                else if (re2.indexIn(_(data)) != -1)
                    maybeHandleInferiorPidChanged(re2.cap(1));
                else if (re3.indexIn(_(data)) != -1)
                    maybeHandleInferiorPidChanged(re3.cap(1));
            }

            // Show some messages to give the impression something happens.
            if (data.startsWith("Reading symbols from ")) {
                showStatusMessage(tr("Reading %1...").arg(_(data.mid(21))), 1000);
                invalidateSourcesList();
            } else if (data.startsWith("[New ") || data.startsWith("[Thread ")) {
                if (data.endsWith('\n'))
                    data.chop(1);
                showStatusMessage(_(data), 1000);
            }
            break;
        }

        case '@': {
            readDebugeeOutput(GdbMi::parseCString(from, to));
            break;
        }

        case '&': {
            QByteArray data = GdbMi::parseCString(from, to);
            m_pendingLogStreamOutput += data;
            // On Windows, the contents seem to depend on the debugger
            // version and/or OS version used.
            if (data.startsWith("warning:"))
                showMessage(_(data.mid(9)), AppStuff); // cut "warning: "
            break;
        }

        case '^': {
            GdbResponse response;

            response.token = token;

            for (inner = from; inner != to; ++inner)
                if (*inner < 'a' || *inner > 'z')
                    break;

            QByteArray resultClass = QByteArray::fromRawData(from, inner - from);
            if (resultClass == "done") {
                response.resultClass = GdbResultDone;
            } else if (resultClass == "running") {
                if (m_progress) {
                    m_progress->setProgressValue(100);
                    m_progress->reportFinished();
                }
                if (state() == InferiorStopped) { // Result of manual command.
                    resetLocation();
                    setTokenBarrier();
                    setState(InferiorRunningRequested);
                }
                setState(InferiorRunning);
                showStatusMessage(tr("Running..."));
                response.resultClass = GdbResultRunning;
            } else if (resultClass == "connected") {
                response.resultClass = GdbResultConnected;
            } else if (resultClass == "error") {
                response.resultClass = GdbResultError;
            } else if (resultClass == "exit") {
                response.resultClass = GdbResultExit;
            } else {
                response.resultClass = GdbResultUnknown;
            }

            from = inner;
            if (from != to) {
                if (*from == ',') {
                    ++from;
                    response.data.parseTuple_helper(from, to);
                    response.data.m_type = GdbMi::Tuple;
                    response.data.m_name = "data";
                } else {
                    // Archer has this
                    response.data.m_type = GdbMi::Tuple;
                    response.data.m_name = "data";
                }
            }

            //qDebug() << "\nLOG STREAM:" + m_pendingLogStreamOutput;
            //qDebug() << "\nCONSOLE STREAM:" + m_pendingConsoleStreamOutput;
            response.data.setStreamOutput("logstreamoutput",
                m_pendingLogStreamOutput);
            response.data.setStreamOutput("consolestreamoutput",
                m_pendingConsoleStreamOutput);
            m_pendingLogStreamOutput.clear();
            m_pendingConsoleStreamOutput.clear();

            handleResultRecord(&response);
            break;
        }
        default: {
            qDebug() << "UNKNOWN RESPONSE TYPE" << c;
            break;
        }
    }
}

void GdbEngine::readGdbStandardError()
{
    QByteArray err = gdbProc()->readAllStandardError();
    showMessage(_("UNEXPECTED GDB STDERR: " + err));
    if (err == "Undefined command: \"bb\".  Try \"help\".\n")
        return;
    if (err.startsWith("BFD: reopening"))
        return;
    qWarning() << "Unexpected gdb stderr:" << err;
}

void GdbEngine::readGdbStandardOutput()
{
    if (m_commandTimer->isActive())
        m_commandTimer->start(); // Retrigger

    int newstart = 0;
    int scan = m_inbuffer.size();

    m_inbuffer.append(gdbProc()->readAllStandardOutput());

    // This can trigger when a dialog starts a nested event loop
    if (m_busy)
        return;

    while (newstart < m_inbuffer.size()) {
        int start = newstart;
        int end = m_inbuffer.indexOf('\n', scan);
        if (end < 0) {
            m_inbuffer.remove(0, start);
            return;
        }
        newstart = end + 1;
        scan = newstart;
        if (end == start)
            continue;
#        if defined(Q_OS_WIN)
        if (m_inbuffer.at(end - 1) == '\r') {
            --end;
            if (end == start)
                continue;
        }
#        endif
        m_busy = true;
        handleResponse(QByteArray::fromRawData(m_inbuffer.constData() + start, end - start));
        m_busy = false;
    }
    m_inbuffer.clear();
}

void GdbEngine::interruptInferior()
{
    QTC_ASSERT(state() == InferiorRunning, qDebug() << state(); return);

    setState(InferiorStopping);
    showStatusMessage(tr("Stop requested..."), 5000);

    showMessage(_("TRYING TO INTERRUPT INFERIOR"));
    m_gdbAdapter->interruptInferior();
}

void GdbEngine::interruptInferiorTemporarily()
{
    interruptInferior();
    foreach (const GdbCommand &cmd, m_commandsToRunOnTemporaryBreak) {
        if (cmd.flags & LosesChild) {
            setState(InferiorStopping_Kill);
            break;
        }
    }
}

void GdbEngine::maybeHandleInferiorPidChanged(const QString &pid0)
{
    const qint64 pid = pid0.toLongLong();
    if (pid == 0) {
        showMessage(_("Cannot parse PID from %1").arg(pid0));
        return;
    }
    if (pid == inferiorPid())
        return;

    showMessage(_("FOUND PID %1").arg(pid));
    notifyInferiorPid(pid);
}

void GdbEngine::postCommand(const QByteArray &command, AdapterCallback callback,
                            const char *callbackName, const QVariant &cookie)
{
    postCommand(command, NoFlags, callback, callbackName, cookie);
}

void GdbEngine::postCommand(const QByteArray &command, GdbCommandFlags flags,
                            AdapterCallback callback,
                            const char *callbackName, const QVariant &cookie)
{
    GdbCommand cmd;
    cmd.command = command;
    cmd.flags = flags;
    cmd.adapterCallback = callback;
    cmd.callbackName = callbackName;
    cmd.cookie = cookie;
    postCommandHelper(cmd);
}

void GdbEngine::postCommand(const QByteArray &command, GdbCommandCallback callback,
                            const char *callbackName, const QVariant &cookie)
{
    postCommand(command, NoFlags, callback, callbackName, cookie);
}

void GdbEngine::postCommand(const QByteArray &command, GdbCommandFlags flags,
                            GdbCommandCallback callback, const char *callbackName,
                            const QVariant &cookie)
{
    GdbCommand cmd;
    cmd.command = command;
    cmd.flags = flags;
    cmd.callback = callback;
    cmd.callbackName = callbackName;
    cmd.cookie = cookie;
    postCommandHelper(cmd);
}

void GdbEngine::postCommandHelper(const GdbCommand &cmd)
{
    if (!stateAcceptsGdbCommands(state())) {
        PENDING_DEBUG(_("NO GDB PROCESS RUNNING, CMD IGNORED: " + cmd.command));
        showMessage(_("NO GDB PROCESS RUNNING, CMD IGNORED: %1 %2")
            .arg(_(cmd.command)).arg(state()));
        return;
    }

    if (cmd.flags & RebuildWatchModel) {
        ++m_pendingWatchRequests;
        PENDING_DEBUG("   WATCH MODEL:" << cmd.command << "=>" << cmd.callbackName
                      << "INCREMENTS PENDING TO" << m_pendingWatchRequests);
    } else if (cmd.flags & RebuildBreakpointModel) {
        ++m_pendingBreakpointRequests;
        PENDING_DEBUG("   BRWAKPOINT MODEL:" << cmd.command << "=>" << cmd.callbackName
                      << "INCREMENTS PENDING TO" << m_pendingBreakpointRequests);
    } else {
        PENDING_DEBUG("   OTHER (IN):" << cmd.command << "=>" << cmd.callbackName
                      << "LEAVES PENDING WATCH AT" << m_pendingWatchRequests
                      << "LEAVES PENDING BREAKPOINT AT" << m_pendingBreakpointRequests);
    }

    // FIXME: clean up logic below
    if (cmd.flags & Immediate) {
        // This should always be sent.
        flushCommand(cmd);
    } else if ((cmd.flags & NeedsStop)
            || !m_commandsToRunOnTemporaryBreak.isEmpty()) {
        if (state() == InferiorStopped || state() == InferiorUnrunnable
            || state() == InferiorStarting || state() == AdapterStarted) {
            // Can be safely sent now.
            flushCommand(cmd);
        } else {
            // Queue the commands that we cannot send at once.
            showMessage(_("QUEUING COMMAND " + cmd.command));
            m_commandsToRunOnTemporaryBreak.append(cmd);
            if (state() == InferiorStopping) {
                if (cmd.flags & LosesChild)
                    setState(InferiorStopping_Kill);
                showMessage(_("CHILD ALREADY BEING INTERRUPTED. STILL HOPING."));
                // Calling shutdown() here breaks all situations where two
                // NeedsStop commands are issued in quick succession.
            } else if (state() == InferiorStopping_Kill) {
                showMessage(_("CHILD ALREADY BEING INTERRUPTED (KILL PENDING)"));
                // FIXME
                shutdown();
            } else if (state() == InferiorRunningRequested) {
                if (cmd.flags & LosesChild)
                    setState(InferiorRunningRequested_Kill);
                showMessage(_("RUNNING REQUESTED; POSTPONING INTERRUPT"));
            } else if (state() == InferiorRunningRequested_Kill) {
                showMessage(_("RUNNING REQUESTED; POSTPONING INTERRUPT (KILL PENDING)"));
            } else if (state() == InferiorRunning) {
                showStatusMessage(tr("Stopping temporarily"), 1000);
                interruptInferiorTemporarily();
            } else {
                qDebug() << "ATTEMPTING TO QUEUE COMMAND IN INAPPROPRIATE STATE" << state();
            }
        }