qt-creator/src/plugins/debugger/watchutils.cpp

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**
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// NOTE: Don't add dependencies to other files.
// This is used in the debugger auto-tests.

#include "watchutils.h"
#include "watchdata.h"

#include <QDebug>

#include <string.h>
#include <ctype.h>

enum { debug = 0 };

namespace Debugger {
namespace Internal {

QString removeObviousSideEffects(const QString &expIn)
{
    QString exp = expIn.trimmed();
    if (exp.isEmpty() || exp.startsWith(QLatin1Char('#')) || !hasLetterOrNumber(exp) || isKeyWord(exp))
        return QString();

    if (exp.startsWith(QLatin1Char('"')) && exp.endsWith(QLatin1Char('"')))
        return QString();

    if (exp.startsWith(QLatin1String("++")) || exp.startsWith(QLatin1String("--")))
        exp.remove(0, 2);

    if (exp.endsWith(QLatin1String("++")) || exp.endsWith(QLatin1String("--")))
        exp.truncate(exp.size() - 2);

    if (exp.startsWith(QLatin1Char('<')) || exp.startsWith(QLatin1Char('[')))
        return QString();

    if (hasSideEffects(exp) || exp.isEmpty())
        return QString();
    return exp;
}

bool isSkippableFunction(const QString &funcName, const QString &fileName)
{
    if (fileName.endsWith(QLatin1String("/qobject.cpp")))
        return true;
    if (fileName.endsWith(QLatin1String("/moc_qobject.cpp")))
        return true;
    if (fileName.endsWith(QLatin1String("/qmetaobject.cpp")))
        return true;
    if (fileName.endsWith(QLatin1String("/qmetaobject_p.h")))
        return true;
    if (fileName.endsWith(QLatin1String(".moc")))
        return true;

    if (funcName.endsWith(QLatin1String("::qt_metacall")))
        return true;
    if (funcName.endsWith(QLatin1String("::d_func")))
        return true;
    if (funcName.endsWith(QLatin1String("::q_func")))
        return true;

    return false;
}

bool isLeavableFunction(const QString &funcName, const QString &fileName)
{
    if (funcName.endsWith(QLatin1String("QObjectPrivate::setCurrentSender")))
        return true;
    if (funcName.endsWith(QLatin1String("QMutexPool::get")))
        return true;

    if (fileName.endsWith(QLatin1String(".cpp"))) {
        if (fileName.endsWith(QLatin1String("/qmetaobject.cpp"))
                && funcName.endsWith(QLatin1String("QMetaObject::methodOffset")))
            return true;
        if (fileName.endsWith(QLatin1String("/qobject.cpp"))
                && (funcName.endsWith(QLatin1String("QObjectConnectionListVector::at"))
                    || funcName.endsWith(QLatin1String("~QObject"))))
            return true;
        if (fileName.endsWith(QLatin1String("/qmutex.cpp")))
            return true;
        if (fileName.endsWith(QLatin1String("/qthread.cpp")))
            return true;
        if (fileName.endsWith(QLatin1String("/qthread_unix.cpp")))
            return true;
    } else if (fileName.endsWith(QLatin1String(".h"))) {

        if (fileName.endsWith(QLatin1String("/qobject.h")))
            return true;
        if (fileName.endsWith(QLatin1String("/qmutex.h")))
            return true;
        if (fileName.endsWith(QLatin1String("/qvector.h")))
            return true;
        if (fileName.endsWith(QLatin1String("/qlist.h")))
            return true;
        if (fileName.endsWith(QLatin1String("/qhash.h")))
            return true;
        if (fileName.endsWith(QLatin1String("/qmap.h")))
            return true;
        if (fileName.endsWith(QLatin1String("/qshareddata.h")))
            return true;
        if (fileName.endsWith(QLatin1String("/qstring.h")))
            return true;
        if (fileName.endsWith(QLatin1String("/qglobal.h")))
            return true;

    } else {

        if (fileName.contains(QLatin1String("/qbasicatomic")))
            return true;
        if (fileName.contains(QLatin1String("/qorderedmutexlocker_p")))
            return true;
        if (fileName.contains(QLatin1String("/qatomic")))
            return true;
    }

    return false;
}

bool isLetterOrNumber(char c)
{
    return (c >= 'a' && c <= 'z')
        || (c >= 'A' && c <= 'Z')
        || (c >= '0' && c <= '9');
}

bool hasLetterOrNumber(const QString &exp)
{
    const QChar underscore = QLatin1Char('_');
    for (int i = exp.size(); --i >= 0; )
        if (exp.at(i).isLetterOrNumber() || exp.at(i) == underscore)
            return true;
    return false;
}

bool hasSideEffects(const QString &exp)
{
    // FIXME: complete?
    return exp.contains(QLatin1String("-="))
        || exp.contains(QLatin1String("+="))
        || exp.contains(QLatin1String("/="))
        || exp.contains(QLatin1String("%="))
        || exp.contains(QLatin1String("*="))
        || exp.contains(QLatin1String("&="))
        || exp.contains(QLatin1String("|="))
        || exp.contains(QLatin1String("^="))
        || exp.contains(QLatin1String("--"))
        || exp.contains(QLatin1String("++"));
}

bool isKeyWord(const QString &exp)
{
    // FIXME: incomplete.
    if (!exp.isEmpty())
        return false;
    switch (exp.at(0).toLatin1()) {
    case 'a':
        return exp == QLatin1String("auto");
    case 'b':
        return exp == QLatin1String("break");
    case 'c':
        return exp == QLatin1String("case") || exp == QLatin1String("class")
               || exp == QLatin1String("const") || exp == QLatin1String("constexpr")
               || exp == QLatin1String("catch") || exp == QLatin1String("continue")
               || exp == QLatin1String("const_cast");
    case 'd':
        return exp == QLatin1String("do") || exp == QLatin1String("default")
               || exp == QLatin1String("delete") || exp == QLatin1String("decltype")
               || exp == QLatin1String("dynamic_cast");
    case 'e':
        return exp == QLatin1String("else") || exp == QLatin1String("extern")
               || exp == QLatin1String("enum") || exp == QLatin1String("explicit");
    case 'f':
        return exp == QLatin1String("for") || exp == QLatin1String("friend");  // 'final'?
    case 'g':
        return exp == QLatin1String("goto");
    case 'i':
        return exp == QLatin1String("if") || exp == QLatin1String("inline");
    case 'n':
        return exp == QLatin1String("new") || exp == QLatin1String("namespace")
               || exp == QLatin1String("noexcept");
    case 'm':
        return exp == QLatin1String("mutable");
    case 'o':
        return exp == QLatin1String("operator"); // 'override'?
    case 'p':
        return exp == QLatin1String("public") || exp == QLatin1String("protected")
               || exp == QLatin1String("private");
    case 'r':
        return exp == QLatin1String("return") || exp == QLatin1String("register")
               || exp == QLatin1String("reinterpret_cast");
    case 's':
        return exp == QLatin1String("struct") || exp == QLatin1String("switch")
               || exp == QLatin1String("static_cast");
    case 't':
        return exp == QLatin1String("template") || exp == QLatin1String("typename")
               || exp == QLatin1String("try") || exp == QLatin1String("throw")
               || exp == QLatin1String("typedef");
    case 'u':
        return exp == QLatin1String("union") || exp == QLatin1String("using");
    case 'v':
        return exp == QLatin1String("void") || exp == QLatin1String("volatile")
               || exp == QLatin1String("virtual");
    case 'w':
        return exp == QLatin1String("while");
    }
    return false;
}

bool startsWithDigit(const QString &str)
{
    return !str.isEmpty() && str.at(0).isDigit();
}

QByteArray stripPointerType(QByteArray type)
{
    if (type.endsWith('*'))
        type.chop(1);
    if (type.endsWith("* const"))
        type.chop(7);
    if (type.endsWith(' '))
        type.chop(1);
    return type;
}

// Format a hex address with colons as in the memory editor.
QString formatToolTipAddress(quint64 a)
{
    QString rc = QString::number(a, 16);
    if (a) {
        if (const int remainder = rc.size() % 4)
            rc.prepend(QString(4 - remainder, QLatin1Char('0')));
        const QChar colon = QLatin1Char(':');
        switch (rc.size()) {
        case 16:
            rc.insert(12, colon);
        case 12:
            rc.insert(8, colon);
        case 8:
            rc.insert(4, colon);
        }
    }
    return QLatin1String("0x") + rc;
}

QByteArray gdbQuoteTypes(const QByteArray &type)
{
    // gdb does not understand sizeof(Core::IDocument*).
    // "sizeof('Core::IDocument*')" is also not acceptable,
    // it needs to be "sizeof('Core::IDocument'*)"
    //
    // We never will have a perfect solution here (even if we had a full blown
    // C++ parser as we do not have information on what is a type and what is
    // a variable name. So "a<b>::c" could either be two comparisons of values
    // 'a', 'b' and '::c', or a nested type 'c' in a template 'a<b>'. We
    // assume here it is the latter.
    //return type;

    // (*('myns::QPointer<myns::QObject>*'*)0x684060)" is not acceptable
    // (*('myns::QPointer<myns::QObject>'**)0x684060)" is acceptable
    if (isPointerType(type))
        return gdbQuoteTypes(stripPointerType(type)) + '*';

    QByteArray accu;
    QByteArray result;
    int templateLevel = 0;

    const char colon = ':';
    const char singleQuote = '\'';
    const char lessThan = '<';
    const char greaterThan = '>';
    for (int i = 0; i != type.size(); ++i) {
        const char c = type.at(i);
        if (isLetterOrNumber(c) || c == '_' || c == colon || c == ' ') {
            accu += c;
        } else if (c == lessThan) {
            ++templateLevel;
            accu += c;
        } else if (c == greaterThan) {
            --templateLevel;
            accu += c;
        } else if (templateLevel > 0) {
            accu += c;
        } else {
            if (accu.contains(colon) || accu.contains(lessThan))
                result += singleQuote + accu + singleQuote;
            else
                result += accu;
            accu.clear();
            result += c;
        }
    }
    if (accu.contains(colon) || accu.contains(lessThan))
        result += singleQuote + accu + singleQuote;
    else
        result += accu;
    //qDebug() << "GDB_QUOTING" << type << " TO " << result;

    return result;
}


} // namespace Internal
} // namespace Debugger