Linux: Add a crash handler providing a backtrace for debug builds.

Use case: You're working with a debug version of Qt Creator and you're
interested in getting a backtrace displayed as soon as Qt Creator
crashes without searching for the core file, starting your debugger, ...

Once a 'serious signal' (currently SIGILL, SIGFPE, SIGSEGV, SIGBUS,
SIGPIPE) is delivered, a popup displays the following debug information:

 - Qt Creator version (same as in the about dialog)
 - Kernel version (uname -a)
 - GNU/Linux Distribution (/etc/lsb-release)
 - Backtrace (by gdb)

Please note that this crash handler is built and used only in debug mode
on GNU/Linux. It's solely meant as a convenience tool for the developer.

In contrast to the breakpad integration, this crash handler operates
'offline'. There is no network i/o involved.

Change-Id: Idcfb1bf1ad68942615ecfe0dffc0d03154455049
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
Reviewed-by: hjk <qthjk@ovi.com>

17 files changed, 1217 insertions, 2 deletions

diff --git a/src/app/app.pro b/src/app/app.pro
index 896b2cc884..85831adb6f 100644
--- a/src/app/app.pro
+++ b/src/app/app.pro
@@ -6,6 +6,13 @@ TARGET = $$IDE_APP_TARGET
 DESTDIR = $$IDE_APP_PATH
 
 SOURCES += main.cpp
+linux-* {
+    # Build only in debug mode.
+    debug_and_release|CONFIG(debug, debug|release) {
+        HEADERS += ../tools/qtcreatorcrashhandler/crashhandlersetup.h
+        SOURCES += ../tools/qtcreatorcrashhandler/crashhandlersetup.cpp
+    }
+}
 
 include(../rpath.pri)
 
diff --git a/src/app/main.cpp b/src/app/main.cpp
index 526ca15477..e96692b04f 100644
--- a/src/app/main.cpp
+++ b/src/app/main.cpp
@@ -29,6 +29,7 @@
 **************************************************************************/
 
 #include "qtsingleapplication.h"
+#include "../tools/qtcreatorcrashhandler/crashhandlersetup.h"
 
 #include <app/app_version.h>
 #include <extensionsystem/iplugin.h>
@@ -228,6 +229,8 @@ int main(int argc, char **argv)
     const int threadCount = QThreadPool::globalInstance()->maxThreadCount();
     QThreadPool::globalInstance()->setMaxThreadCount(qMax(4, 2 * threadCount));
 
+    setupCrashHandler(); // Display a backtrace once a serious signal is delivered.
+
 #ifdef ENABLE_QT_BREAKPAD
     QtSystemExceptionHandler systemExceptionHandler;
 #endif
@@ -432,5 +435,7 @@ int main(int argc, char **argv)
         QTimer::singleShot(100, &pluginManager, SLOT(startTests()));
 #endif
 
-    return app.exec();
+    const int r = app.exec();
+    cleanupCrashHandler();
+    return r;
 }
diff --git a/src/tools/qtcreatorcrashhandler/backtracecollector.cpp b/src/tools/qtcreatorcrashhandler/backtracecollector.cpp
new file mode 100644
index 0000000000..df8500000f
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/backtracecollector.cpp
@@ -0,0 +1,119 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#include "backtracecollector.h"
+
+#include <QDebug>
+#include <QScopedPointer>
+#include <QTemporaryFile>
+
+const char GdbBatchCommands[] =
+        "set height 0\n"
+        "set width 0\n"
+        "thread\n"
+        "thread apply all backtrace full\n";
+
+class BacktraceCollectorPrivate
+{
+public:
+    BacktraceCollectorPrivate() : errorOccurred(false) {}
+
+    bool errorOccurred;
+    QScopedPointer<QTemporaryFile> commandFile;
+    QProcess debugger;
+    QString output;
+};
+
+BacktraceCollector::BacktraceCollector(QObject *parent) :
+    QObject(parent), d(new BacktraceCollectorPrivate)
+{
+    connect(&d->debugger, SIGNAL(finished(int,QProcess::ExitStatus)),
+            SLOT(onDebuggerFinished(int,QProcess::ExitStatus)));
+    connect(&d->debugger, SIGNAL(error(QProcess::ProcessError)),
+            SLOT(onDebuggerError(QProcess::ProcessError)));
+    connect(&d->debugger, SIGNAL(readyRead()), SLOT(onDebuggerOutputAvailable()));
+    d->debugger.setProcessChannelMode(QProcess::MergedChannels);
+}
+
+BacktraceCollector::~BacktraceCollector()
+{
+    delete d;
+}
+
+void BacktraceCollector::run(Q_PID pid)
+{
+    d->debugger.start(QLatin1String("gdb"), QStringList()
+        << QLatin1String("--nw") // Do not use a window interface.
+        << QLatin1String("--nx") // Do not read .gdbinit file.
+        << QLatin1String("--batch") // Exit after processing options.
+        << QLatin1String("--command") << createTemporaryCommandFile()
+        << QLatin1String("--pid") << QString::number(pid)
+    );
+}
+
+void BacktraceCollector::onDebuggerFinished(int exitCode, QProcess::ExitStatus /*exitStatus*/)
+{
+    if (d->errorOccurred) {
+        emit error(QLatin1String("QProcess: ") + d->debugger.errorString());
+        return;
+    }
+    if (exitCode != 0) {
+        emit error(QString::fromLatin1("Debugger exited with code %1.").arg(exitCode));
+        return;
+    }
+    emit backtrace(d->output);
+}
+
+void BacktraceCollector::onDebuggerError(QProcess::ProcessError /*error*/)
+{
+    d->errorOccurred = true;
+}
+
+QString BacktraceCollector::createTemporaryCommandFile()
+{
+    d->commandFile.reset(new QTemporaryFile);
+    if (!d->commandFile->open()) {
+        emit error(QLatin1String("Error: Could not create temporary command file."));
+        return QString();
+    }
+    if (d->commandFile->write(GdbBatchCommands) == -1) {
+        emit error(QLatin1String("Error: Could not write temporary command file."));
+        return QString();
+    }
+    d->commandFile->close();
+    return d->commandFile->fileName();
+}
+
+void BacktraceCollector::onDebuggerOutputAvailable()
+{
+    const QString newChunk = d->debugger.readAll();
+    d->output.append(newChunk);
+    emit backtraceChunk(newChunk);
+}
diff --git a/src/tools/qtcreatorcrashhandler/backtracecollector.h b/src/tools/qtcreatorcrashhandler/backtracecollector.h
new file mode 100644
index 0000000000..151d7c09d1
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/backtracecollector.h
@@ -0,0 +1,63 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#ifndef BACKTRACECOLLECTOR_H
+#define BACKTRACECOLLECTOR_H
+
+#include <QProcess>
+
+class BacktraceCollectorPrivate;
+
+class BacktraceCollector : public QObject
+{
+    Q_OBJECT
+public:
+    explicit BacktraceCollector(QObject *parent = 0);
+    ~BacktraceCollector();
+
+    void run(Q_PID pid);
+
+signals:
+    void error(const QString &errorMessage);
+    void backtrace(const QString &backtrace);
+    void backtraceChunk(const QString &chunk);
+
+private slots:
+    void onDebuggerOutputAvailable();
+    void onDebuggerFinished(int exitCode, QProcess::ExitStatus exitStatus);
+    void onDebuggerError(QProcess::ProcessError err);
+
+private:
+    QString createTemporaryCommandFile();
+
+    BacktraceCollectorPrivate *d;
+};
+
+#endif // BACKTRACECOLLECTOR_H
diff --git a/src/tools/qtcreatorcrashhandler/crashhandler.cpp b/src/tools/qtcreatorcrashhandler/crashhandler.cpp
new file mode 100644
index 0000000000..dfc5e5012f
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/crashhandler.cpp
@@ -0,0 +1,250 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#include "crashhandler.h"
+#include "crashhandlerdialog.h"
+#include "backtracecollector.h"
+#include "utils.h"
+
+#include <QApplication>
+#include <QDebug>
+#include <QDesktopServices>
+#include <QFile>
+#include <QRegExp>
+#include <QTextStream>
+#include <QUrl>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <errno.h>
+#include <unistd.h>
+
+#include <sys/types.h>
+
+static const char FileDistroInformation[] = "/etc/lsb-release";
+static const char FileKernelVersion[] = "/proc/version";
+
+static QString collectLinuxDistributionInfo()
+{
+    return QString::fromLatin1(fileContents(QLatin1String(FileDistroInformation)));
+}
+
+static QString collectKernelVersionInfo()
+{
+    return QString::fromLatin1(fileContents(QLatin1String(FileKernelVersion)));
+}
+
+class CrashHandlerPrivate
+{
+public:
+    CrashHandlerPrivate(pid_t pid, CrashHandler *crashHandler)
+        : pid(pid), dialog(crashHandler), argv(0), envp(0) {}
+
+    ~CrashHandlerPrivate()
+    {
+        if (argv) {
+            for (int i = 0; argv[i]; ++i)
+                delete[] argv[i];
+        }
+        if (envp) {
+            for (int i = 0; envp[i]; ++i)
+                delete[] envp[i];
+        }
+        free(argv);
+        free(envp);
+    }
+
+    pid_t pid;
+    BacktraceCollector backtraceCollector;
+    CrashHandlerDialog dialog;
+
+    // For restarting the process.
+    char **argv;
+    char **envp;
+};
+
+CrashHandler::CrashHandler(pid_t pid, QObject *parent)
+    : QObject(parent), d(new CrashHandlerPrivate(pid, this))
+{
+    connect(&d->backtraceCollector, SIGNAL(error(QString)), SLOT(onError(QString)));
+    connect(&d->backtraceCollector, SIGNAL(backtraceChunk(QString)), SLOT(onBacktraceChunk(QString)));
+    connect(&d->backtraceCollector, SIGNAL(backtrace(QString)), SLOT(onBacktraceFinished(QString)));
+
+    d->dialog.appendDebugInfo(collectKernelVersionInfo());
+    d->dialog.appendDebugInfo(collectLinuxDistributionInfo());
+    d->dialog.show();
+
+    if (!collectRestartAppData()) // If we can't restart the app properly, ...
+        d->dialog.disableRestartAppButton();
+}
+
+CrashHandler::~CrashHandler()
+{
+    delete d;
+}
+
+void CrashHandler::run()
+{
+    d->backtraceCollector.run(d->pid);
+}
+
+void CrashHandler::onError(const QString &errorMessage)
+{
+    d->dialog.setToFinalState();
+
+    QTextStream(stderr) << errorMessage;
+    const QString text = QLatin1String("There occured a problem providing the backtrace. "
+        "Please make sure to have the debugger \"gdb\" installed.\n");
+    d->dialog.appendDebugInfo(text);
+    d->dialog.appendDebugInfo(errorMessage);
+}
+
+void CrashHandler::onBacktraceChunk(const QString &chunk)
+{
+    d->dialog.appendDebugInfo(chunk);
+    QTextStream out(stdout);
+    out << chunk;
+}
+
+void CrashHandler::onBacktraceFinished(const QString &backtrace)
+{
+    d->dialog.setToFinalState();
+
+    // Select first line of relevant thread.
+
+    // Example debugger output:
+    // ...
+    // [Current thread is 1 (Thread 0x7f1c33c79780 (LWP 975))]
+    // ...
+    // Thread 1 (Thread 0x7f1c33c79780 (LWP 975)):
+    // ...
+    QRegExp rx("\\[Current thread is (\\d+)");
+    const int pos = rx.indexIn(backtrace);
+    if (pos == -1)
+        return;
+    const QString threadNumber = rx.cap(1);
+    const QString textToSelect = QString::fromLatin1("Thread %1").arg(threadNumber);
+    d->dialog.selectLineWithContents(textToSelect);
+}
+
+void CrashHandler::openBugTracker()
+{
+    QDesktopServices::openUrl(QUrl(URL_BUGTRACKER));
+}
+
+bool CrashHandler::collectRestartAppData()
+{
+    const QString procDir = QString::fromLatin1("/proc/%1").arg(d->pid);
+
+    // Construct d->argv.
+    // man 5 proc: /proc/[pid]/cmdline
+    // The command-line arguments appear in this file as a set of strings separated by
+    // null bytes ('\0'), with a further null byte after the last string.
+    const QString procCmdFileName = procDir + QLatin1String("/cmdline");
+    QList<QByteArray> cmdEntries = fileContents(procCmdFileName).split('\0');
+    if (cmdEntries.size() < 2) {
+        qWarning("%s: Unexpected format in file '%s'.\n", Q_FUNC_INFO, qPrintable(procCmdFileName));
+        return false;
+    }
+    cmdEntries.removeLast();
+    char * const executable = qstrdup(qPrintable(cmdEntries.takeFirst()));
+    d->argv = (char **) malloc(sizeof(char*) * (cmdEntries.size() + 2));
+    if (d->argv == 0)
+        qFatal("%s: malloc() failed.\n", Q_FUNC_INFO);
+    d->argv[0] = executable;
+    int i;
+    for (i = 1; i <= cmdEntries.size(); ++i)
+        d->argv[i] = qstrdup(cmdEntries.at(i-1));
+    d->argv[i] = 0;
+
+    // Construct d->envp.
+    // man 5 proc: /proc/[pid]/environ
+    // The entries are separated by null bytes ('\0'), and there may be a null  byte at the end.
+    const QString procEnvFileName = procDir + QLatin1String("/environ");
+    QList<QByteArray> envEntries = fileContents(procEnvFileName).split('\0');
+    if (envEntries.isEmpty()) {
+        qWarning("%s: Unexpected format in file '%s'.\n", Q_FUNC_INFO, qPrintable(procEnvFileName));
+        return false;
+    }
+    if (envEntries.last().isEmpty())
+        envEntries.removeLast();
+    d->envp = (char **) malloc(sizeof(char*) * (envEntries.size() + 1));
+    if (d->envp == 0)
+        qFatal("%s: malloc() failed.\n", Q_FUNC_INFO);
+    for (i = 0; i < envEntries.size(); ++i)
+        d->envp[i] = qstrdup(envEntries.at(i));
+    d->envp[i] = 0;
+
+    return true;
+}
+
+void CrashHandler::restartApplication()
+{
+    // TODO: If QTBUG-2284 is resolved, use QProcess::startDetached() here.
+    // Close the crash handler and start the process again with same environment and
+    // command line arguments.
+    //
+    // We can't use QProcess::startDetached because of bug
+    //
+    //      QTBUG-2284
+    //      QProcess::startDetached does not support setting an environment for the new process
+    //
+    // therefore, we use fork-exec.
+
+    pid_t pid = fork();
+    switch (pid) {
+    case -1: // error
+        qFatal("%s: fork() failed.", Q_FUNC_INFO);
+        break;
+    case 0: // child
+        qDebug("Restarting Qt Creator with\n");
+        for (int i = 0; d->argv[i]; ++i)
+            qDebug("   %s", d->argv[i]);
+        qDebug("\nand environment\n");
+        for (int i = 0; d->envp[i]; ++i)
+            qDebug("   %s", d->envp[i]);
+
+        // The standards pipes must be open, otherwise the restarted Qt Creator will
+        // receive a SIGPIPE as soon as these are used.
+        if (freopen("/dev/null", "r", stdin) == 0)
+            qFatal("%s: freopen() failed for stdin: %s.\n", Q_FUNC_INFO, strerror(errno));
+        if (freopen("/dev/null", "w", stdout) == 0)
+            qFatal("%s: freopen() failed for stdout: %s.\n", Q_FUNC_INFO, strerror(errno));
+        if (freopen("/dev/null", "w", stderr) == 0)
+            qFatal("%s: freopen() failed for stderr: %s.\n.", Q_FUNC_INFO, strerror(errno));
+
+        execve(d->argv[0], d->argv, d->envp);
+        _exit(EXIT_FAILURE);
+    default: // parent
+        qApp->quit();
+        break;
+    }
+}
diff --git a/src/tools/qtcreatorcrashhandler/crashhandler.h b/src/tools/qtcreatorcrashhandler/crashhandler.h
new file mode 100644
index 0000000000..f834befb75
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/crashhandler.h
@@ -0,0 +1,66 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#ifndef CRASHHANDLER_H
+#define CRASHHANDLER_H
+
+#include <QObject>
+
+QT_BEGIN_NAMESPACE
+class QString;
+QT_END_NAMESPACE
+
+class ApplicationInfo;
+class CrashHandlerPrivate;
+
+class CrashHandler : public QObject
+{
+    Q_OBJECT
+public:
+    explicit CrashHandler(pid_t pid, QObject *parent = 0);
+    ~CrashHandler();
+
+    void run();
+
+public slots:
+    void onError(const QString &errorMessage);
+    void onBacktraceChunk(const QString &chunk);
+    void onBacktraceFinished(const QString &backtrace);
+
+    void openBugTracker();
+    void restartApplication();
+
+private:
+    bool collectRestartAppData();
+
+    CrashHandlerPrivate *d;
+};
+
+#endif // CRASHHANDLER_H
diff --git a/src/tools/qtcreatorcrashhandler/crashhandlerdialog.cpp b/src/tools/qtcreatorcrashhandler/crashhandlerdialog.cpp
new file mode 100644
index 0000000000..d1ff87d270
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/crashhandlerdialog.cpp
@@ -0,0 +1,132 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#include "crashhandler.h"
+#include "crashhandlerdialog.h"
+#include "ui_crashhandlerdialog.h"
+#include "utils.h"
+
+#include <app/app_version.h>
+
+#include <QClipboard>
+#include <QIcon>
+
+CrashHandlerDialog::CrashHandlerDialog(CrashHandler *handler, QWidget *parent) :
+    QDialog(parent),
+    m_crashHandler(handler),
+    m_ui(new Ui::CrashHandlerDialog)
+{
+    m_ui->setupUi(this);
+    m_ui->introLabel->setTextFormat(Qt::RichText);
+    m_ui->introLabel->setOpenExternalLinks(true);
+    m_ui->debugInfoEdit->setReadOnly(true);
+    m_ui->progressBar->setMinimum(0);
+    m_ui->progressBar->setMaximum(0);
+
+    const QStyle * const style = QApplication::style();
+    m_ui->closeButton->setIcon(style->standardIcon(QStyle::SP_DialogCloseButton));
+
+    const int iconSize = style->pixelMetric(QStyle::PM_MessageBoxIconSize, 0);
+    QIcon icon = style->standardIcon(QStyle::SP_MessageBoxCritical);
+    m_ui->iconLabel->setPixmap(icon.pixmap(iconSize, iconSize));
+
+    connect(m_ui->copyToClipBoardButton, SIGNAL(clicked()), this, SLOT(copyToClipboardClicked()));
+    connect(m_ui->reportBugButton, SIGNAL(clicked()), m_crashHandler, SLOT(openBugTracker()));
+    connect(m_ui->restartAppButton, SIGNAL(clicked()), m_crashHandler, SLOT(restartApplication()));
+    connect(m_ui->closeButton, SIGNAL(clicked()), qApp, SLOT(quit()));
+
+    setApplicationInfo();
+}
+
+CrashHandlerDialog::~CrashHandlerDialog()
+{
+    delete m_ui;
+}
+
+void CrashHandlerDialog::setToFinalState()
+{
+    m_ui->progressBar->hide();
+    m_ui->copyToClipBoardButton->setEnabled(true);
+    m_ui->reportBugButton->setEnabled(true);
+}
+
+void CrashHandlerDialog::disableRestartAppButton()
+{
+    m_ui->restartAppButton->setDisabled(true);
+}
+
+void CrashHandlerDialog::setApplicationInfo()
+{
+    const QString ideName = QLatin1String("Qt Creator");
+    const QString contents = tr(
+        "<p><b>%1 has closed unexpectedly.</b></p>"
+        "<p>Please file a <a href='%2'>bug report</a> with the debug information provided below.</p>")
+        .arg(ideName, QLatin1String(URL_BUGTRACKER));
+    m_ui->introLabel->setText(contents);
+
+    QString revision;
+#ifdef IDE_REVISION
+     revision = tr(" from revision %1").arg(QString::fromLatin1(Core::Constants::IDE_REVISION_STR).left(10));
+#endif
+    const QString versionInformation = tr(
+        "%1 %2%3, built on %4 at %5, based on Qt %6 (%7 bit)\n")
+            .arg(ideName, QLatin1String(Core::Constants::IDE_VERSION_LONG), revision,
+                 QLatin1String(__DATE__), QLatin1String(__TIME__), QLatin1String(QT_VERSION_STR),
+                 QString::number(QSysInfo::WordSize));
+    m_ui->debugInfoEdit->append(versionInformation);
+}
+
+void CrashHandlerDialog::appendDebugInfo(const QString &chunk)
+{
+    m_ui->debugInfoEdit->append(chunk);
+}
+
+void CrashHandlerDialog::selectLineWithContents(const QString &text)
+{
+    // The selected line will be the first line visible.
+
+    // Go to end.
+    QTextCursor cursor = m_ui->debugInfoEdit->textCursor();
+    cursor.movePosition(QTextCursor::End);
+    m_ui->debugInfoEdit->setTextCursor(cursor);
+
+    // Find text by searching backwards.
+    m_ui->debugInfoEdit->find(text, QTextDocument::FindCaseSensitively | QTextDocument::FindBackward);
+
+    // Highlight whole line.
+    cursor = m_ui->debugInfoEdit->textCursor();
+    cursor.select(QTextCursor::LineUnderCursor);
+    m_ui->debugInfoEdit->setTextCursor(cursor);
+}
+
+void CrashHandlerDialog::copyToClipboardClicked()
+{
+    QApplication::clipboard()->setText(m_ui->debugInfoEdit->toPlainText());
+}
diff --git a/src/tools/qtcreatorcrashhandler/crashhandlerdialog.h b/src/tools/qtcreatorcrashhandler/crashhandlerdialog.h
new file mode 100644
index 0000000000..ecee4cffa9
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/crashhandlerdialog.h
@@ -0,0 +1,67 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#ifndef CRASHHANDLERDIALOG_H
+#define CRASHHANDLERDIALOG_H
+
+#include <QDialog>
+
+QT_BEGIN_NAMESPACE
+namespace Ui {
+class CrashHandlerDialog;
+}
+QT_END_NAMESPACE
+
+class CrashHandler;
+
+class CrashHandlerDialog : public QDialog
+{
+    Q_OBJECT
+
+public:
+    explicit CrashHandlerDialog(CrashHandler *handler, QWidget *parent = 0);
+    ~CrashHandlerDialog();
+
+public:
+    void disableRestartAppButton();
+    void setApplicationInfo();
+    void setToFinalState();
+    void appendDebugInfo(const QString &chunk);
+    void selectLineWithContents(const QString &text);
+
+private slots:
+    void copyToClipboardClicked();
+
+private:
+    CrashHandler *m_crashHandler;
+    Ui::CrashHandlerDialog *m_ui;
+};
+
+#endif // CRASHHANDLERDIALOG_H
diff --git a/src/tools/qtcreatorcrashhandler/crashhandlerdialog.ui b/src/tools/qtcreatorcrashhandler/crashhandlerdialog.ui
new file mode 100644
index 0000000000..101efd2e48
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/crashhandlerdialog.ui
@@ -0,0 +1,122 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>CrashHandlerDialog</class>
+ <widget class="QDialog" name="CrashHandlerDialog">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>600</width>
+    <height>800</height>
+   </rect>
+  </property>
+  <property name="minimumSize">
+   <size>
+    <width>400</width>
+    <height>300</height>
+   </size>
+  </property>
+  <property name="windowTitle">
+   <string>Dialog</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout_2">
+     <property name="sizeConstraint">
+      <enum>QLayout::SetDefaultConstraint</enum>
+     </property>
+     <item>
+      <widget class="QLabel" name="iconLabel">
+       <property name="text">
+        <string>Icon</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QLabel" name="introLabel">
+       <property name="text">
+        <string>Some useful information here...</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <spacer name="horizontalSpacer_2">
+       <property name="orientation">
+        <enum>Qt::Horizontal</enum>
+       </property>
+       <property name="sizeHint" stdset="0">
+        <size>
+         <width>40</width>
+         <height>20</height>
+        </size>
+       </property>
+      </spacer>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <widget class="QProgressBar" name="progressBar">
+     <property name="value">
+      <number>24</number>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <widget class="QTextEdit" name="debugInfoEdit"/>
+   </item>
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout">
+     <item>
+      <widget class="QPushButton" name="copyToClipBoardButton">
+       <property name="enabled">
+        <bool>false</bool>
+       </property>
+       <property name="text">
+        <string>C&amp;opy to clipboard</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QPushButton" name="reportBugButton">
+       <property name="enabled">
+        <bool>false</bool>
+       </property>
+       <property name="text">
+        <string>Report this &amp;bug</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <spacer name="horizontalSpacer">
+       <property name="orientation">
+        <enum>Qt::Horizontal</enum>
+       </property>
+       <property name="sizeHint" stdset="0">
+        <size>
+         <width>40</width>
+         <height>20</height>
+        </size>
+       </property>
+      </spacer>
+     </item>
+     <item>
+      <widget class="QPushButton" name="restartAppButton">
+       <property name="text">
+        <string>&amp;Restart Qt Creator</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QPushButton" name="closeButton">
+       <property name="text">
+        <string>&amp;Close</string>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/src/tools/qtcreatorcrashhandler/crashhandlersetup.cpp b/src/tools/qtcreatorcrashhandler/crashhandlersetup.cpp
new file mode 100644
index 0000000000..658429aabb
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/crashhandlersetup.cpp
@@ -0,0 +1,133 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#include "crashhandlersetup.h"
+
+#include <QtGlobal>
+
+#if !defined(QT_NO_DEBUG) && defined(Q_OS_LINUX)
+#define BUILD_CRASH_HANDLER
+#endif
+
+#ifdef BUILD_CRASH_HANDLER
+
+#include <QApplication>
+#include <QDebug>
+#include <QString>
+
+#include <stdlib.h>
+
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#ifdef Q_WS_X11
+#include <qx11info_x11.h>
+#include <X11/Xlib.h>
+#endif
+
+static const char *crashHandlerPathC;
+static void *signalHandlerStack;
+
+extern "C" void signalHandler(int /*signal*/)
+{
+#ifdef Q_WS_X11
+    // Kill window since it's frozen anyway.
+    if (QX11Info::display())
+        close(ConnectionNumber(QX11Info::display()));
+#endif
+    pid_t pid = fork();
+    switch (pid) {
+    case -1: // error
+        break;
+    case 0: // child
+        execl(crashHandlerPathC, crashHandlerPathC, (char *) 0);
+        _exit(EXIT_FAILURE);
+    default: // parent
+        waitpid(pid, 0, 0);
+        _exit(EXIT_FAILURE);
+        break;
+    }
+}
+#endif // BUILD_CRASH_HANDLER
+
+void setupCrashHandler()
+{
+#ifdef BUILD_CRASH_HANDLER
+    const QString crashHandlerPath = qApp->applicationDirPath()
+        + QLatin1String("/qtcreator_crash_handler");
+    crashHandlerPathC = qstrdup(qPrintable(crashHandlerPath));
+
+    // Setup an alternative stack for the signal handler. This way we are able to handle SIGSEGV
+    // even if the normal process stack is exhausted.
+    stack_t ss;
+    ss.ss_sp = signalHandlerStack = malloc(SIGSTKSZ); // Usual requirements for alternative signal stack.
+    if (ss.ss_sp == 0) {
+        qWarning("Warning: Could not allocate space for alternative signal stack (%s).", Q_FUNC_INFO);
+        return;
+    }
+    ss.ss_size = SIGSTKSZ;
+    ss.ss_flags = 0;
+    if (sigaltstack(&ss, 0) == -1) {
+        qWarning("Warning: Failed to set alternative signal stack (%s).", Q_FUNC_INFO);
+        return;
+    }
+
+    // Install signal handler for calling the crash handler.
+    struct sigaction sa;
+    if (sigemptyset(&sa.sa_mask) == -1) {
+        qWarning("Warning: Failed to empty signal set (%s).", Q_FUNC_INFO);
+        return;
+    }
+    sa.sa_handler = &signalHandler;
+    // SA_RESETHAND - Restore signal action to default after signal handler has been called.
+    // SA_NODEFER - Don't block the signal after it was triggered (otherwise blocked signals get
+    // inherited via fork() and execve()). Without this the signal will not be delivered to the
+    // restarted Qt Creator.
+    // SA_ONSTACK - Use alternative stack.
+    sa.sa_flags = SA_RESETHAND | SA_NODEFER | SA_ONSTACK;
+    const int signalsToHandle[] = { SIGILL, SIGFPE, SIGSEGV, SIGBUS, SIGPIPE, 0 };
+    for (int i = 0; signalsToHandle[i]; ++i) {
+        if (sigaction(signalsToHandle[i], &sa, 0) == -1 )
+            qWarning("Warning: Failed to install signal handler for SIGILL (%s).", Q_FUNC_INFO);
+    }
+#endif // BUILD_CRASH_HANDLER
+}
+
+void cleanupCrashHandler()
+{
+#ifdef BUILD_CRASH_HANDLER
+    delete[] crashHandlerPathC;
+    free(signalHandlerStack);
+#endif
+}
diff --git a/src/tools/qtcreatorcrashhandler/crashhandlersetup.h b/src/tools/qtcreatorcrashhandler/crashhandlersetup.h
new file mode 100644
index 0000000000..698cd5f9a6
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/crashhandlersetup.h
@@ -0,0 +1,37 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#ifndef CRASHHANDLERSETUP_H
+#define CRASHHANDLERSETUP_H
+
+void setupCrashHandler();
+void cleanupCrashHandler();
+
+#endif // CRASHHANDLERSETUP_H
diff --git a/src/tools/qtcreatorcrashhandler/main.cpp b/src/tools/qtcreatorcrashhandler/main.cpp
new file mode 100644
index 0000000000..94c21db2db
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/main.cpp
@@ -0,0 +1,68 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#include "crashhandler.h"
+#include "utils.h"
+
+#include <QApplication>
+#include <QFile>
+#include <QProcess>
+#include <QString>
+#include <QStyle>
+#include <QTextStream>
+
+#include <stdlib.h>
+
+#include <sys/types.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[])
+{
+    QApplication app(argc, argv);
+    app.setApplicationName(QLatin1String(APPLICATION_NAME));
+    app.setWindowIcon(QApplication::style()->standardIcon(QStyle::SP_MessageBoxCritical));
+
+    // Check usage.
+    Q_PID parentPid = getppid();
+    QString parentExecutable = QFile::symLinkTarget(QString::fromLatin1("/proc/%1/exe")
+        .arg(QString::number(parentPid)));
+    if (argc > 1 || !parentExecutable.contains("qtcreator")) {
+        QTextStream err(stderr);
+        err << QString::fromLatin1("This crash handler will be called by Qt Creator itself. "
+                                   "Don't call this manually.\n");
+        return EXIT_FAILURE;
+    }
+
+    // Run.
+    CrashHandler *crashHandler = new CrashHandler(parentPid);
+    crashHandler->run();
+
+    return app.exec();
+}
diff --git a/src/tools/qtcreatorcrashhandler/qtcreatorcrashhandler.pro b/src/tools/qtcreatorcrashhandler/qtcreatorcrashhandler.pro
new file mode 100644
index 0000000000..551de3008d
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/qtcreatorcrashhandler.pro
@@ -0,0 +1,26 @@
+include(../../../qtcreator.pri)
+
+TARGET = qtcreator_crash_handler
+DESTDIR = $$IDE_BIN_PATH
+
+CONFIG -= app_bundle
+TEMPLATE = app
+
+SOURCES += \
+    main.cpp \
+    backtracecollector.cpp \
+    crashhandlerdialog.cpp \
+    crashhandler.cpp \
+    utils.cpp
+
+HEADERS += \
+    backtracecollector.h \
+    crashhandlerdialog.h \
+    crashhandler.h \
+    utils.h
+
+FORMS += \
+    crashhandlerdialog.ui
+
+target.path = /bin
+INSTALLS += target
diff --git a/src/tools/qtcreatorcrashhandler/qtcreatorcrashhandler.qbs b/src/tools/qtcreatorcrashhandler/qtcreatorcrashhandler.qbs
new file mode 100644
index 0000000000..820f26d68c
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/qtcreatorcrashhandler.qbs
@@ -0,0 +1,28 @@
+import qbs.base 1.0
+import "../QtcTool.qbs" as QtcTool
+
+QtcTool {
+    name: "qtcreator_crash_handler"
+    condition: qbs.targetOS == "linux" && qbs.buildVariant == "debug"
+
+    cpp.includePaths: [
+        buildDirectory
+    ]
+
+    Depends { name: "cpp" }
+    Depends { name: "Qt.widgets" }
+    Depends { name: "app_version_header" }
+
+    files: [
+        "main.cpp",
+        "backtracecollector.cpp",
+        "backtracecollector.h",
+        "crashhandlerdialog.cpp",
+        "crashhandlerdialog.h",
+        "crashhandler.cpp",
+        "crashhandler.h",
+        "utils.cpp",
+        "utils.h",
+        "crashhandlerdialog.ui"
+    ]
+}
diff --git a/src/tools/qtcreatorcrashhandler/utils.cpp b/src/tools/qtcreatorcrashhandler/utils.cpp
new file mode 100644
index 0000000000..aca361bab7
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/utils.cpp
@@ -0,0 +1,44 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#include "utils.h"
+
+#include <QDebug>
+#include <QFile>
+
+QByteArray fileContents(const QString &filePath)
+{
+    QFile file(filePath);
+    if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
+        qWarning("Warning: Could not open '%s'.", qPrintable(filePath));
+        return QByteArray();
+    }
+    return file.readAll();
+}
diff --git a/src/tools/qtcreatorcrashhandler/utils.h b/src/tools/qtcreatorcrashhandler/utils.h
new file mode 100644
index 0000000000..0979d248de
--- /dev/null
+++ b/src/tools/qtcreatorcrashhandler/utils.h
@@ -0,0 +1,42 @@
+/**************************************************************************
+**
+** 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.
+**
+**
+**************************************************************************/
+
+#ifndef UTILS_H
+#define UTILS_H
+
+#include <QByteArray>
+#include <QString>
+
+const char APPLICATION_NAME[] = "Qt Creator Crash Handler";
+const char URL_BUGTRACKER[] = "https://bugreports.qt-project.org/";
+
+QByteArray fileContents(const QString &filePath);
+
+#endif // UTILS_H
diff --git a/src/tools/tools.pro b/src/tools/tools.pro
index dcbb5bb6de..879144711b 100644
--- a/src/tools/tools.pro
+++ b/src/tools/tools.pro
@@ -21,5 +21,11 @@ win32 {
 QT_BREAKPAD_ROOT_PATH = $$(QT_BREAKPAD_ROOT_PATH)
 !isEmpty(QT_BREAKPAD_ROOT_PATH) {
     SUBDIRS += qtcrashhandler
+} else {
+    linux-* {
+        # Build only in debug mode.
+        debug_and_release|CONFIG(debug, debug|release) {
+            SUBDIRS += qtcreatorcrashhandler
+        }
+    }
 }
-