gdbengine.cpp

/**************************************************************************
**
** This file is part of Qt Creator
**
** Copyright (c) 2012 Nokia Corporation and/or its subsidiary(-ies).
**
** Contact: http://www.qt-project.org/
**
**
** GNU Lesser General Public License Usage
**
** 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.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** Other Usage
**
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
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**************************************************************************/

#include "gdbengine.h"

#include "debuggerstartparameters.h"
#include "debuggerinternalconstants.h"
#include "debuggerruncontrolfactory.h"
#include "disassemblerlines.h"
#include "attachgdbadapter.h"
#include "coregdbadapter.h"
#include "localplaingdbadapter.h"
#include "termgdbadapter.h"
#include "remotegdbserveradapter.h"
#include "remoteplaingdbadapter.h"

#include "debuggeractions.h"
#include "debuggerconstants.h"
#include "debuggercore.h"
#include "debuggerplugin.h"
#include "debuggerrunner.h"
#include "debuggerstringutils.h"
#include "debuggertooltipmanager.h"
#include "disassembleragent.h"
#include "gdbmi.h"
#include "gdboptionspage.h"
#include "memoryagent.h"
#include "watchutils.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 "debuggersourcepathmappingwidget.h"
#include "hostutils.h"
#include "logwindow.h"
#include "procinterrupt.h"

#include <coreplugin/icore.h>
#include <coreplugin/idocument.h>
#include <extensionsystem/pluginmanager.h>
#include <projectexplorer/abi.h>
#include <projectexplorer/projectexplorerconstants.h>
#include <projectexplorer/taskhub.h>
#include <projectexplorer/itaskhandler.h>
#include <texteditor/itexteditor.h>
#include <utils/elfreader.h>
#include <utils/qtcassert.h>
#include <utils/qtcprocess.h>
#include <utils/savedaction.h>

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

#include <QAction>
#include <QDialogButtonBox>
#include <QLabel>
#include <QMessageBox>
#include <QPushButton>

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

using namespace ProjectExplorer;
using namespace Utils;

namespace Debugger {
namespace Internal {

class GdbToolTipContext : public DebuggerToolTipContext
{
public:
    GdbToolTipContext(const DebuggerToolTipContext &c) :
        DebuggerToolTipContext(c), editor(0) {}

    QPoint mousePosition;
    QString expression;
    QByteArray iname;
    Core::IEditor *editor;
};

enum { debugPending = 0 };

#define PENDING_DEBUG(s) do { if (debugPending) qDebug() << s; } while (0)

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

QByteArray GdbEngine::tooltipIName(const QString &exp)
{
    return "tooltip." + exp.toLatin1().toHex();
}

static bool stateAcceptsGdbCommands(DebuggerState state)
{
    switch (state) {
    case EngineSetupRequested:
    case EngineSetupOk:
    case EngineSetupFailed:
    case InferiorUnrunnable:
    case InferiorSetupRequested:
    case InferiorSetupFailed:
    case EngineRunRequested:
    case InferiorRunRequested:
    case InferiorRunOk:
    case InferiorStopRequested:
    case InferiorStopOk:
    case InferiorShutdownRequested:
    case EngineShutdownRequested:
    case InferiorShutdownOk:
    case InferiorShutdownFailed:
        return true;
    case DebuggerNotReady:
    case InferiorStopFailed:
    case InferiorSetupOk:
    case EngineRunFailed:
    case InferiorExitOk:
    case InferiorRunFailed:
    case EngineShutdownOk:
    case EngineShutdownFailed:
    case DebuggerFinished:
        return false;
    }
    return false;
}

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

static QByteArray parsePlainConsoleStream(const GdbResponse &response)
{
    QByteArray out = response.consoleStreamOutput;
    // 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);
}

///////////////////////////////////////////////////////////////////////
//
// Debuginfo Taskhandler
//
///////////////////////////////////////////////////////////////////////

class DebugInfoTask
{
public:
    QString command;
};

class DebugInfoTaskHandler : public  ProjectExplorer::ITaskHandler
{
public:
    explicit DebugInfoTaskHandler(GdbEngine *engine)
        : m_engine(engine)
    {}

    bool canHandle(const Task &task) const
    {
        return m_debugInfoTasks.contains(task.taskId);
    }

    void handle(const Task &task)
    {
        m_engine->requestDebugInformation(m_debugInfoTasks.value(task.taskId));
    }

    void addTask(unsigned id, const DebugInfoTask &task)
    {
        m_debugInfoTasks[id] = task;
    }

    QAction *createAction(QObject *parent) const
    {
        QAction *action = new QAction(DebuggerPlugin::tr("Install &Debug Information"), parent);
        action->setToolTip(DebuggerPlugin::tr("This tries to install missing debug information."));
        return action;
    }

private:
    GdbEngine *m_engine;
    QHash<unsigned, DebugInfoTask> m_debugInfoTasks;
};

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

GdbEngine::GdbEngine(const DebuggerStartParameters &startParameters)
  : DebuggerEngine(startParameters)
{
    setObjectName(_("GdbEngine"));

    m_busy = false;
    m_debuggingHelperState = DebuggingHelperUninitialized;
    m_gdbVersion = 100;
    m_gdbBuildVersion = -1;
    m_isMacGdb = false;
    m_isQnxGdb = false;
    m_hasBreakpointNotifications = false;
    m_hasPython = false;
    m_registerNamesListed = false;
    m_hasInferiorThreadList = false;
    m_sourcesListUpdating = false;
    m_oldestAcceptableToken = -1;
    m_nonDiscardableCount = 0;
    m_outputCodec = QTextCodec::codecForLocale();
    m_pendingBreakpointRequests = 0;
    m_commandsDoneCallback = 0;
    m_stackNeeded = false;
    m_preparedForQmlBreak = false;
    m_disassembleUsesComma = false;
    m_terminalTrap = startParameters.useTerminal;
    m_fullStartDone = false;
    m_forceAsyncModel = false;

    invalidateSourcesList();

    m_debugInfoTaskHandler = new DebugInfoTaskHandler(this);
    ExtensionSystem::PluginManager::addObject(m_debugInfoTaskHandler);

    m_commandTimer.setSingleShot(true);
    connect(&m_commandTimer, SIGNAL(timeout()), SLOT(commandTimeout()));

    connect(debuggerCore()->action(AutoDerefPointers), SIGNAL(valueChanged(QVariant)),
            SLOT(reloadLocals()));
    connect(debuggerCore()->action(CreateFullBacktrace), SIGNAL(triggered()),
            SLOT(createFullBacktrace()));
    connect(debuggerCore()->action(UseDebuggingHelpers), SIGNAL(valueChanged(QVariant)),
            SLOT(reloadLocals()));
    connect(debuggerCore()->action(UseDynamicType), SIGNAL(valueChanged(QVariant)),
            SLOT(reloadLocals()));
}

GdbEngine::~GdbEngine()
{
    ExtensionSystem::PluginManager::removeObject(m_debugInfoTaskHandler);
    delete m_debugInfoTaskHandler;
    m_debugInfoTaskHandler = 0;

    // Prevent sending error messages afterwards.
    disconnect();
}

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

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.\n%2")
                .arg(m_gdb, gdbProc()->errorString());
        case QProcess::Crashed:
            if (targetState() == DebuggerFinished)
                return tr("The gdb process crashed some time after starting "
                    "successfully.");
            else
                return tr("The gdb process was ended forcefully");
        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

// Parse "~:gdb: unknown target exception 0xc0000139 at 0x77bef04e\n"
// and return an exception message
static inline QString msgWinException(const QByteArray &data)
{
    const int exCodePos = data.indexOf("0x");
    const int blankPos = exCodePos != -1 ? data.indexOf(' ', exCodePos + 1) : -1;
    const int addressPos = blankPos != -1 ? data.indexOf("0x", blankPos + 1) : -1;
    if (addressPos < 0)
        return GdbEngine::tr("An exception was triggered.");
    const unsigned exCode = data.mid(exCodePos, blankPos - exCodePos).toUInt(0, 0);
    const quint64 address = data.mid(addressPos).trimmed().toULongLong(0, 0);
    QString rc;
    QTextStream str(&rc);
    str << GdbEngine::tr("An exception was triggered: ");
#ifdef Q_OS_WIN
    formatWindowsException(exCode, address, 0, 0, 0, str);
#else
    Q_UNUSED(exCode)
    Q_UNUSED(address)
#endif
    str << '.';
    return rc;
}

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

static bool isNameChar(char c)
{
    // could be 'stopped' or 'shlibs-added'
    return (c >= 'a' && c <= 'z') || c == '-';
}

static bool contains(const QByteArray &message, const char *pattern, int size)
{
    const int s = message.size();
    if (s < size)
        return false;
    const int pos = message.indexOf(pattern);
    if (pos == -1)
        return false;
    const bool beginFits = pos == 0 || message.at(pos - 1) == '\n';
    const bool endFits = pos + size == s || message.at(pos + size) == '\n';
    return beginFits && endFits;
}

static bool isGdbConnectionError(const QByteArray &message)
{
    // Handle messages gdb client produces when the target exits (gdbserver)
    //
    // we get this as response either to a specific command, e.g.
    //    31^error,msg="Remote connection closed"
    // or as informative output:
    //    &Remote connection closed

    const char msg1[] = "Remote connection closed";
    const char msg2[] = "Remote communication error.  Target disconnected.: No error.";
    const char msg3[] = "Quit";

    return contains(message, msg1, sizeof(msg1) - 1)
        || contains(message, msg2, sizeof(msg2) - 1)
        || contains(message, msg3, sizeof(msg3) - 1);
}

void GdbEngine::handleResponse(const QByteArray &buff)
{
    showMessage(QString::fromLocal8Bit(buff, buff.length()), LogOutput);

    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;
    }

    // Next char decides kind of response.
    const char c = *from++;
    switch (c) {
        case '*':
        case '+':
        case '=': {
            QByteArray asyncClass;
            for (; from != to; ++from) {
                const char c = *from;
                if (!isNameChar(c))
                    break;
                asyncClass += *from;
            }

            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") {
                if (state() == InferiorRunOk || state() == InferiorSetupRequested) {
                    // We get multiple *running after thread creation and in Windows terminals.
                    showMessage(QString::fromLatin1("NOTE: INFERIOR STILL RUNNING IN STATE %1.").
                                arg(QLatin1String(DebuggerEngine::stateName(state()))));
                } else {
                    notifyInferiorRunOk();
                }
            } 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"

                // id="/lib/i386-linux-gnu/libc.so.6"
                // target-name="/lib/i386-linux-gnu/libc.so.6"
                // host-name="/lib/i386-linux-gnu/libc.so.6"
                // symbols-loaded="0",thread-group="i1"
                QByteArray id = result.findChild("id").data();
                if (!id.isEmpty())
                    showStatusMessage(tr("Library %1 loaded").arg(_(id)), 1000);
                progressPing();
                invalidateSourcesList();
                Module module;
                module.startAddress = 0;
                module.endAddress = 0;
                module.hostPath = _(result.findChild("host-name").data());
                module.modulePath = _(result.findChild("target-name").data());
                module.moduleName = QFileInfo(module.hostPath).baseName();
                modulesHandler()->updateModule(module);
            } 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();
                progressPing();
                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.
                progressPing();
                // 7.1.50 has thread-group-started,id="i1",pid="3529"
                QByteArray id = result.findChild("id").data();
                showStatusMessage(tr("Thread group %1 created").arg(_(id)), 1000);
                int pid = id.toInt();
                if (!pid) {
                    id = result.findChild("pid").data();
                    pid = id.toInt();
                }
                if (pid)
                    notifyInferiorPid(pid);
                handleThreadGroupCreated(result);
            } 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);
                handleThreadGroupExited(result);
            } 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 BreakpointResponseId rid(bkpt.findChild("number").data());
                if (!isQmlStepBreakpoint(rid)) {
                    BreakHandler *handler = breakHandler();
                    BreakpointModelId id = handler->findBreakpointByResponseId(rid);
                    BreakpointResponse br = handler->response(id);
                    updateResponse(br, bkpt);
                    handler->setResponse(id, br);
                    attemptAdjustBreakpointLocation(id);
                }
            } else if (asyncClass == "breakpoint-modified") {
                // New in FSF gdb since 2011-04-27.
                // "{bkpt={number="3",type="breakpoint",disp="keep",
                // enabled="y",addr="<MULTIPLE>",times="1",
                // original-location="\\",simple_gdbtest_app.cpp\\":135"},
                // {number="3.1",enabled="y",addr="0x0805ff68",
                // func="Vector<int>::Vector(int)",
                // file="simple_gdbtest_app.cpp",
                // fullname="/data/...line="135"},{number="3.2"...}}"

                // Note the leading comma in original-location. Filter it out.
                // We don't need the field anyway.
                QByteArray ba = result.toString();
                ba = '[' + ba.mid(6, ba.size() - 7) + ']';
                const int pos1 = ba.indexOf(",original-location");
                const int pos2 = ba.indexOf("\":", pos1 + 2);
                const int pos3 = ba.indexOf('"', pos2 + 2);
                ba.remove(pos1, pos3 - pos1 + 1);
                result = GdbMi();
                result.fromString(ba);
                BreakHandler *handler = breakHandler();
                BreakpointModelId id;
                BreakpointResponse br;
                foreach (const GdbMi &bkpt, result.children()) {
                    const QByteArray nr = bkpt.findChild("number").data();
                    BreakpointResponseId rid(nr);
                    if (!isHiddenBreakpoint(rid)) {
                        if (nr.contains('.')) {
                            // A sub-breakpoint.
                            BreakpointResponse sub;
                            updateResponse(sub, bkpt);
                            sub.id = rid;
                            sub.type = br.type;
                            handler->insertSubBreakpoint(id, sub);
                        } else {
                            // A primary breakpoint.
                            id = handler->findBreakpointByResponseId(rid);
                            //qDebug() << "NR: " << nr << "RID: " << rid
                            //    << "ID: " << id;
                            //BreakpointModelId id =
                            //    handler->findBreakpointByResponseId(rid);
                            br = handler->response(id);
                            updateResponse(br, bkpt);
                            handler->setResponse(id, br);
                        }
                    }
                }
                m_hasBreakpointNotifications = true;
            } else if (asyncClass == "breakpoint-created") {
                // "{bkpt={number="1",type="breakpoint",disp="del",enabled="y",
                //  addr="<PENDING>",pending="main",times="0",
                //  original-location="main"}}" -- or --
                // {bkpt={number="2",type="hw watchpoint",disp="keep",enabled="y",
                //  what="*0xbfffed48",times="0",original-location="*0xbfffed48"
                BreakHandler *handler = breakHandler();
                foreach (const GdbMi &bkpt, result.children()) {
                    BreakpointResponse br;
                    br.type = BreakpointByFileAndLine;
                    updateResponse(br, bkpt);
                    handler->handleAlienBreakpoint(br, this);
                }
            } else if (asyncClass == "breakpoint-deleted") {
                // "breakpoint-deleted" "{id="1"}"
                // New in FSF gdb since 2011-04-27.
                BreakHandler *handler = breakHandler();
                QByteArray nr = result.findChild("id").data();
                BreakpointResponseId rid(nr);
                BreakpointModelId id = handler->findBreakpointByResponseId(rid);
                if (id.isValid()) {
                    // This also triggers when a temporary breakpoint is hit.
                    // We do not really want that, as this loses all information.
                    // FIXME: Use a special marker for this case?
                    if (!handler->isOneShot(id))
                        handler->removeAlienBreakpoint(id);
                }
            } 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);
                progressPing();
                invalidateSourcesList();
            } else if (data.startsWith("[New ") || data.startsWith("[Thread ")) {
                if (data.endsWith('\n'))
                    data.chop(1);
                progressPing();
                showStatusMessage(_(data), 1000);
            } else if (data.startsWith("gdb: unknown target exception 0x")) {
                // [Windows, most likely some DLL/Entry point not found]:
                // "gdb: unknown target exception 0xc0000139 at 0x77bef04e"
                // This may be fatal and cause the target to exit later
                m_lastWinException = msgWinException(data);
                showMessage(m_lastWinException, LogMisc);
            }

            if (data.startsWith("QMLBP:")) {
                int pos1 = 6;
                int pos2 = data.indexOf(' ', pos1);
                m_qmlBreakpointResponseId2 = BreakpointResponseId(data.mid(pos1, pos2 - pos1));
                //qDebug() << "FOUND QMLBP: " << m_qmlBreakpointNumbers[2];
                //qDebug() << "CURRENT: " << m_qmlBreakpointNumbers;
            }

            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: "

            if (isGdbConnectionError(data)) {
                notifyInferiorExited();
                break;
            }

            // From SuSE's gdb: >&"Missing separate debuginfo for ...\n"
            // ">&"Try: zypper install -C \"debuginfo(build-id)=c084ee5876ed1ac12730181c9f07c3e027d8e943\"\n"
            if (data.startsWith("Missing separate debuginfo for ")) {
                m_lastMissingDebugInfo = QString::fromLocal8Bit(data.mid(32));
            } else if (data.startsWith("Try: zypper")) {
                QString cmd = QString::fromLocal8Bit(data.mid(4));

                Task task(Task::Warning,
                    tr("Missing debug information for %1\nTry: %2")
                        .arg(m_lastMissingDebugInfo).arg(cmd),
                    FileName(), 0, Core::Id("Debuginfo"));

                taskHub()->addTask(task);

                DebugInfoTask dit;
                dit.command = cmd;
                m_debugInfoTaskHandler->addTask(task.taskId, dit);
            }

            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") {
                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.logStreamOutput = m_pendingLogStreamOutput;
            response.consoleStreamOutput =  m_pendingConsoleStreamOutput;
            m_pendingLogStreamOutput.clear();
            m_pendingConsoleStreamOutput.clear();

            handleResultRecord(&response);
            break;
        }
        default: {
            qDebug() << "UNKNOWN RESPONSE TYPE '" << c << "'. REST: " << from;
            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()
{
    m_commandTimer.start(); // Restart timer.

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

    QByteArray out = gdbProc()->readAllStandardOutput();
    m_inbuffer.append(out);

    // 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 (m_inbuffer.at(end - 1) == '\r') {
            --end;
            if (end == start)
                continue;
        }
        m_busy = true;
        QByteArray ba = QByteArray::fromRawData(m_inbuffer.constData() + start, end - start);
        handleResponse(ba);
        m_busy = false;
    }
    m_inbuffer.clear();
}

void GdbEngine::interruptInferior()
{
    QTC_ASSERT(state() == InferiorStopRequested,
        qDebug() << "INTERRUPT INFERIOR: " << state(); return);

    if (usesExecInterrupt()) {
        postCommand("-exec-interrupt", Immediate);
    } else {
        showStatusMessage(tr("Stop requested..."), 5000);
        showMessage(_("TRYING TO INTERRUPT INFERIOR"));
        interruptInferior2();
    }
}

void GdbEngine::interruptInferiorTemporarily()
{
    foreach (const GdbCommand &cmd, m_commandsToRunOnTemporaryBreak) {
        if (cmd.flags & LosesChild) {
            notifyInferiorIll();