// Copyright (C) 2016 The Qt Company Ltd. // Copyright (C) 2016 Intel Corporation. // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only #include "qdebug.h" #include "private/qdebug_p.h" #include "qmetaobject.h" #include #include #include #include #include QT_BEGIN_NAMESPACE using namespace QtMiscUtils; /* Returns a human readable representation of the first \a maxSize characters in \a data. The size, \a len, is a 64-bit quantity to avoid truncation due to implicit conversions in callers. */ QByteArray QtDebugUtils::toPrintable(const char *data, qint64 len, qsizetype maxSize) { if (!data) return "(null)"; QByteArray out; for (qsizetype i = 0; i < qMin(len, maxSize); ++i) { char c = data[i]; if (isAsciiPrintable(c)) { out += c; } else { switch (c) { case '\n': out += "\\n"; break; case '\r': out += "\\r"; break; case '\t': out += "\\t"; break; default: { const char buf[] = { '\\', 'x', toHexLower(uchar(c) / 16), toHexLower(uchar(c) % 16), 0 }; out += buf; } } } } if (maxSize < len) out += "..."; return out; } // This file is needed to force compilation of QDebug into the kernel library. /*! \class QDebug \inmodule QtCore \ingroup shared \brief The QDebug class provides an output stream for debugging information. QDebug is used whenever the developer needs to write out debugging or tracing information to a device, file, string or console. \section1 Basic Use In the common case, it is useful to call the qDebug() function to obtain a default QDebug object to use for writing debugging information. \snippet qdebug/qdebugsnippet.cpp 1 This constructs a QDebug object using the constructor that accepts a QtMsgType value of QtDebugMsg. Similarly, the qWarning(), qCritical() and qFatal() functions also return QDebug objects for the corresponding message types. The class also provides several constructors for other situations, including a constructor that accepts a QFile or any other QIODevice subclass that is used to write debugging information to files and other devices. The constructor that accepts a QString is used to write to a string for display or serialization. \section1 Formatting Options QDebug formats output so that it's easily readable. It automatically adds spaces between arguments, and adds quotes around QString, QByteArray, QChar arguments. You can tweak these options through the space(), nospace() and quote(), noquote() methods. Furthermore, \l{QTextStream manipulators} can be piped into a QDebug stream. QDebugStateSaver limits changes to the formatting to the current scope. resetFormat() resets the options to the default ones. \section1 Writing Custom Types to a Stream Many standard types can be written to QDebug objects, and Qt provides support for most Qt value types. To add support for custom types, you need to implement a streaming operator, as in the following example: \snippet qdebug/qdebugsnippet.cpp 0 This is described in the \l{Debugging Techniques} and \l{Creating Custom Qt Types#Making the Type Printable}{Creating Custom Qt Types} documents. */ /*! \fn QDebug::QDebug(QIODevice *device) Constructs a debug stream that writes to the given \a device. */ /*! \fn QDebug::QDebug(QString *string) Constructs a debug stream that writes to the given \a string. */ /*! \fn QDebug::QDebug(QtMsgType t) Constructs a debug stream that writes to the handler for the message type \a t. */ /*! \fn QDebug::QDebug(const QDebug &o) Constructs a copy of the other debug stream \a o. */ /*! \fn QDebug &QDebug::operator=(const QDebug &other) Assigns the \a other debug stream to this stream and returns a reference to this stream. */ /*! \fn QDebug::~QDebug() Flushes any pending data to be written and destroys the debug stream. */ QDebug::~QDebug() { if (stream && !--stream->ref) { if (stream->space && stream->buffer.endsWith(u' ')) stream->buffer.chop(1); if (stream->message_output) { QInternalMessageLogContext ctxt(stream->context); qt_message_output(stream->type, ctxt, stream->buffer); } delete stream; } } /*! \internal */ void QDebug::putUcs4(uint ucs4) { maybeQuote('\''); if (ucs4 < 0x20) { stream->ts << "\\x" << Qt::hex << ucs4 << Qt::reset; } else if (ucs4 < 0x80) { stream->ts << char(ucs4); } else { if (ucs4 < 0x10000) stream->ts << "\\u" << qSetFieldWidth(4); else stream->ts << "\\U" << qSetFieldWidth(8); stream->ts << Qt::hex << qSetPadChar(u'0') << ucs4 << Qt::reset; } maybeQuote('\''); } // These two functions return true if the character should be printed by QDebug. // For QByteArray, this is technically identical to US-ASCII isprint(); // for QString, we use QChar::isPrint, which requires a full UCS-4 decode. static inline bool isPrintable(char32_t ucs4) { return QChar::isPrint(ucs4); } static inline bool isPrintable(char16_t uc) { return QChar::isPrint(uc); } static inline bool isPrintable(uchar c) { return isAsciiPrintable(c); } template static inline void putEscapedString(QTextStreamPrivate *d, const Char *begin, size_t length, bool isUnicode = true) { QChar quote(u'"'); d->write("e, 1); bool lastWasHexEscape = false; const Char *end = begin + length; for (const Char *p = begin; p != end; ++p) { // check if we need to insert "" to break an hex escape sequence if (Q_UNLIKELY(lastWasHexEscape)) { if (fromHex(*p) != -1) { // yes, insert it QChar quotes[] = { quote, quote }; d->write(quotes, 2); } lastWasHexEscape = false; } if (sizeof(Char) == sizeof(QChar)) { // Surrogate characters are category Cs (Other_Surrogate), so isPrintable = false for them qsizetype runLength = 0; while (p + runLength != end && isPrintable(p[runLength]) && p[runLength] != '\\' && p[runLength] != '"') ++runLength; if (runLength) { d->write(reinterpret_cast(p), runLength); p += runLength - 1; continue; } } else if (isPrintable(*p) && *p != '\\' && *p != '"') { QChar c = QLatin1Char(*p); d->write(&c, 1); continue; } // print as an escape sequence (maybe, see below for surrogate pairs) qsizetype buflen = 2; char16_t buf[std::char_traits::length("\\U12345678")]; buf[0] = '\\'; switch (*p) { case '"': case '\\': buf[1] = *p; break; case '\b': buf[1] = 'b'; break; case '\f': buf[1] = 'f'; break; case '\n': buf[1] = 'n'; break; case '\r': buf[1] = 'r'; break; case '\t': buf[1] = 't'; break; default: if (!isUnicode) { // print as hex escape buf[1] = 'x'; buf[2] = toHexUpper(uchar(*p) >> 4); buf[3] = toHexUpper(uchar(*p)); buflen = 4; lastWasHexEscape = true; break; } if (QChar::isHighSurrogate(*p)) { if ((p + 1) != end && QChar::isLowSurrogate(p[1])) { // properly-paired surrogates char32_t ucs4 = QChar::surrogateToUcs4(*p, p[1]); if (isPrintable(ucs4)) { buf[0] = *p; buf[1] = p[1]; buflen = 2; } else { buf[1] = 'U'; buf[2] = '0'; // toHexUpper(ucs4 >> 32); buf[3] = '0'; // toHexUpper(ucs4 >> 28); buf[4] = toHexUpper(ucs4 >> 20); buf[5] = toHexUpper(ucs4 >> 16); buf[6] = toHexUpper(ucs4 >> 12); buf[7] = toHexUpper(ucs4 >> 8); buf[8] = toHexUpper(ucs4 >> 4); buf[9] = toHexUpper(ucs4); buflen = 10; } ++p; break; } // improperly-paired surrogates, fall through } buf[1] = 'u'; buf[2] = toHexUpper(char16_t(*p) >> 12); buf[3] = toHexUpper(char16_t(*p) >> 8); buf[4] = toHexUpper(*p >> 4); buf[5] = toHexUpper(*p); buflen = 6; } d->write(reinterpret_cast(buf), buflen); } d->write("e, 1); } /*! \internal Duplicated from QtTest::toPrettyUnicode(). */ void QDebug::putString(const QChar *begin, size_t length) { if (stream->noQuotes) { // no quotes, write the string directly too (no pretty-printing) // this respects the QTextStream state, though stream->ts.d_ptr->putString(begin, qsizetype(length)); } else { // we'll reset the QTextStream formatting mechanisms, so save the state QDebugStateSaver saver(*this); stream->ts.d_ptr->params.reset(); putEscapedString(stream->ts.d_ptr.data(), reinterpret_cast(begin), length); } } /*! \internal Duplicated from QtTest::toPrettyCString(). */ void QDebug::putByteArray(const char *begin, size_t length, Latin1Content content) { if (stream->noQuotes) { // no quotes, write the string directly too (no pretty-printing) // this respects the QTextStream state, though QString string = content == ContainsLatin1 ? QString::fromLatin1(begin, qsizetype(length)) : QString::fromUtf8(begin, qsizetype(length)); stream->ts.d_ptr->putString(string); } else { // we'll reset the QTextStream formatting mechanisms, so save the state QDebugStateSaver saver(*this); stream->ts.d_ptr->params.reset(); putEscapedString(stream->ts.d_ptr.data(), reinterpret_cast(begin), length, content == ContainsLatin1); } } static QByteArray timeUnit(qint64 num, qint64 den) { using namespace std::chrono; using namespace q20::chrono; if (num == 1 && den > 1) { // sub-multiple of seconds char prefix = '\0'; auto tryprefix = [&](auto d, char c) { static_assert(decltype(d)::num == 1, "not an SI prefix"); if (den == decltype(d)::den) prefix = c; }; // "u" should be "ยต", but debugging output is not always UTF-8-safe tryprefix(std::milli{}, 'm'); tryprefix(std::micro{}, 'u'); tryprefix(std::nano{}, 'n'); tryprefix(std::pico{}, 'p'); tryprefix(std::femto{}, 'f'); tryprefix(std::atto{}, 'a'); // uncommon ones later tryprefix(std::centi{}, 'c'); tryprefix(std::deci{}, 'd'); if (prefix) { char unit[3] = { prefix, 's' }; return QByteArray(unit, sizeof(unit) - 1); } } const char *unit = nullptr; if (num > 1 && den == 1) { // multiple of seconds - but we don't use SI prefixes auto tryunit = [&](auto d, const char *name) { static_assert(decltype(d)::period::den == 1, "not a multiple of a second"); if (unit || num % decltype(d)::period::num) return; unit = name; num /= decltype(d)::period::num; }; tryunit(years{}, "yr"); tryunit(weeks{}, "wk"); tryunit(days{}, "d"); tryunit(hours{}, "h"); tryunit(minutes{}, "min"); } if (!unit) unit = "s"; if (num == 1 && den == 1) return unit; if (Q_UNLIKELY(num < 1 || den < 1)) return QString::asprintf("", num, den).toLatin1(); // uncommon units: will return something like "[2/3]s" // strlen("[/]min") = 6 char buf[2 * (std::numeric_limits::digits10 + 2) + 10]; size_t len = 0; auto appendChar = [&](char c) { Q_ASSERT(len < sizeof(buf)); buf[len++] = c; }; auto appendNumber = [&](qint64 value) { if (value >= 10'000 && (value % 1000) == 0) len += qsnprintf(buf + len, sizeof(buf) - len, "%.6g", double(value)); // "1e+06" else len += qsnprintf(buf + len, sizeof(buf) - len, "%lld", value); }; appendChar('['); appendNumber(num); if (den != 1) { appendChar('/'); appendNumber(den); } appendChar(']'); memcpy(buf + len, unit, strlen(unit)); return QByteArray(buf, len + strlen(unit)); } /*! \since 6.6 \internal Helper to the std::chrono::duration debug streaming output. */ void QDebug::putTimeUnit(qint64 num, qint64 den) { stream->ts << timeUnit(num, den); // ### optimize } namespace { #ifdef QT_SUPPORTS_INT128 constexpr char Q_INT128_MIN_STR[] = "-170141183460469231731687303715884105728"; constexpr int Int128BufferSize = sizeof(Q_INT128_MIN_STR); using Int128Buffer = std::array; // numeric_limits::digits10 may not exist static char *i128ToStringHelper(Int128Buffer &buffer, quint128 n) { auto dst = buffer.data() + buffer.size(); *--dst = '\0'; // NUL-terminate if (n == 0) { *--dst = '0'; // and done } else { while (n != 0) { *--dst = "0123456789"[n % 10]; n /= 10; } } return dst; } #endif // QT_SUPPORTS_INT128 [[maybe_unused]] static const char *int128Warning() { const char *msg = "Qt was not compiled with int128 support."; qWarning("%s", msg); return msg; } } // unnamed namespace /*! \since 6.7 \internal Helper to the qint128 debug streaming output. */ void QDebug::putInt128([[maybe_unused]] const void *p) { #ifdef QT_SUPPORTS_INT128 Q_ASSERT(p); qint128 i; memcpy(&i, p, sizeof(i)); // alignment paranoia if (i == Q_INT128_MIN) { // -i is not representable, hardcode the result: stream->ts << Q_INT128_MIN_STR; } else { Int128Buffer buffer; auto dst = i128ToStringHelper(buffer, i < 0 ? -i : i); if (i < 0) *--dst = '-'; stream->ts << dst; } return; #endif // QT_SUPPORTS_INT128 stream->ts << int128Warning(); } /*! \since 6.7 \internal Helper to the quint128 debug streaming output. */ void QDebug::putUInt128([[maybe_unused]] const void *p) { #ifdef QT_SUPPORTS_INT128 Q_ASSERT(p); quint128 i; memcpy(&i, p, sizeof(i)); // alignment paranoia Int128Buffer buffer; stream->ts << i128ToStringHelper(buffer, i); return; #endif // QT_SUPPORTS_INT128 stream->ts << int128Warning(); } /*! \fn QDebug::swap(QDebug &other) \since 5.0 Swaps this debug stream instance with \a other. This function is very fast and never fails. */ /*! Resets the stream formatting options, bringing it back to its original constructed state. \sa space(), quote() \since 5.4 */ QDebug &QDebug::resetFormat() { stream->ts.reset(); stream->space = true; stream->noQuotes = false; stream->verbosity = DefaultVerbosity; return *this; } /*! \fn QDebug &QDebug::space() Writes a space character to the debug stream and returns a reference to the stream. The stream remembers that automatic insertion of spaces is enabled for future writes. \sa nospace(), maybeSpace() */ /*! \fn QDebug &QDebug::nospace() Disables automatic insertion of spaces and returns a reference to the stream. \sa space(), maybeSpace() */ /*! \fn QDebug &QDebug::maybeSpace() Writes a space character to the debug stream, depending on the current setting for automatic insertion of spaces, and returns a reference to the stream. \sa space(), nospace() */ /*! \fn bool QDebug::autoInsertSpaces() const Returns \c true if this QDebug instance will automatically insert spaces between writes. \since 5.0 \sa QDebugStateSaver */ /*! \fn void QDebug::setAutoInsertSpaces(bool b) Enables automatic insertion of spaces between writes if \a b is true; otherwise automatic insertion of spaces is disabled. \since 5.0 \sa QDebugStateSaver */ /*! \fn bool QDebug::quoteStrings() const \since 6.7 Returns \c true if this QDebug instance will quote strings streamed into it (which is the default). \sa QDebugStateSaver, quote(), noquote(), setQuoteStrings() */ /*! \fn void QDebug::setQuoteStrings(bool b) \since 6.7 Enables quoting of strings streamed into this QDebug instance if \a b is \c true; otherwise quoting is disabled. The default is to quote strings. \sa QDebugStateSaver, quote(), noquote(), quoteStrings() */ /*! \fn QDebug &QDebug::quote() \since 5.4 Enables automatic insertion of quotation characters around QChar, QString and QByteArray contents and returns a reference to the stream. Quoting is enabled by default. \sa noquote(), maybeQuote() */ /*! \fn QDebug &QDebug::noquote() \since 5.4 Disables automatic insertion of quotation characters around QChar, QString and QByteArray contents and returns a reference to the stream. When quoting is disabled, these types are printed without quotation characters and without escaping of non-printable characters. \sa quote(), maybeQuote() */ /*! \fn QDebug &QDebug::maybeQuote(char c) \since 5.4 Writes a character \a c to the debug stream, depending on the current setting for automatic insertion of quotes, and returns a reference to the stream. The default character is a double quote \c{"}. \sa quote(), noquote() */ /*! \fn int QDebug::verbosity() const \since 5.6 Returns the verbosity of the debug stream. Streaming operators can check the value to decide whether verbose output is desired and print more information depending on the level. Higher values indicate that more information is desired. The allowed range is from 0 to 7. The default value is 2. \sa setVerbosity(), VerbosityLevel */ /*! \fn void QDebug::setVerbosity(int verbosityLevel) \since 5.6 Sets the verbosity of the stream to \a verbosityLevel. The allowed range is from 0 to 7. The default value is 2. \sa verbosity(), VerbosityLevel */ /*! \fn QDebug &QDebug::verbosity(int verbosityLevel) \since 5.13 Sets the verbosity of the stream to \a verbosityLevel and returns a reference to the stream. The allowed range is from 0 to 7. The default value is 2. \sa verbosity(), setVerbosity(), VerbosityLevel */ /*! \enum QDebug::VerbosityLevel \since 5.13 This enum describes the range of verbosity levels. \value MinimumVerbosity \value DefaultVerbosity \value MaximumVerbosity \sa verbosity(), setVerbosity() */ /*! \fn QDebug &QDebug::operator<<(QChar t) Writes the character, \a t, to the stream and returns a reference to the stream. Normally, QDebug prints control characters and non-US-ASCII characters as their C escape sequences or their Unicode value (\\u1234). To print non-printable characters without transformation, enable the noquote() functionality, but note that some QDebug backends may not be 8-bit clean and may not be able to represent \c t. */ /*! \fn QDebug &QDebug::operator<<(bool t) Writes the boolean value, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(char t) Writes the character, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(signed short t) Writes the signed short integer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(unsigned short t) Writes then unsigned short integer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(signed int t) Writes the signed integer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(unsigned int t) Writes then unsigned integer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(signed long t) Writes the signed long integer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(unsigned long t) Writes then unsigned long integer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(qint64 t) Writes the signed 64-bit integer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(quint64 t) Writes then unsigned 64-bit integer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(float t) Writes the 32-bit floating point number, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(double t) Writes the 64-bit floating point number, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(const char *t) Writes the '\\0'-terminated UTF-8 string, \a t, to the stream and returns a reference to the stream. The string is never quoted or escaped for the output. Note that QDebug buffers internally as UTF-16 and may need to transform to 8-bit using the locale's codec in order to use some backends, which may cause garbled output (mojibake). Restricting to US-ASCII strings is recommended. */ /*! \fn QDebug &QDebug::operator<<(const char16_t *t) \since 6.0 Writes the u'\\0'-terminated UTF-16 string, \a t, to the stream and returns a reference to the stream. The string is never quoted or escaped for the output. Note that QDebug buffers internally as UTF-16 and may need to transform to 8-bit using the locale's codec in order to use some backends, which may cause garbled output (mojibake). Restricting to US-ASCII strings is recommended. */ /*! \fn QDebug &QDebug::operator<<(char16_t t) \since 5.5 Writes the UTF-16 character, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(char32_t t) \since 5.5 Writes the UTF-32 character, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(const QString &t) Writes the string, \a t, to the stream and returns a reference to the stream. Normally, QDebug prints the string inside quotes and transforms non-printable characters to their Unicode values (\\u1234). To print non-printable characters without transformation, enable the noquote() functionality. Note that some QDebug backends might not be 8-bit clean. Output examples: \snippet code/src_corelib_io_qdebug.cpp 0 */ /*! \since 5.10 \fn QDebug &QDebug::operator<<(QStringView s) Writes the string view, \a s, to the stream and returns a reference to the stream. Normally, QDebug prints the string inside quotes and transforms non-printable characters to their Unicode values (\\u1234). To print non-printable characters without transformation, enable the noquote() functionality. Note that some QDebug backends might not be 8-bit clean. See the QString overload for examples. */ /*! \since 6.0 \fn QDebug &QDebug::operator<<(QUtf8StringView s) Writes the string view, \a s, to the stream and returns a reference to the stream. Normally, QDebug prints the data inside quotes and transforms control or non-US-ASCII characters to their C escape sequences (\\xAB). This way, the output is always 7-bit clean and the string can be copied from the output and pasted back into C++ sources, if necessary. To print non-printable characters without transformation, enable the noquote() functionality. Note that some QDebug backends might not be 8-bit clean. */ /*! \fn QDebug &QDebug::operator<<(QLatin1StringView t) Writes the string, \a t, to the stream and returns a reference to the stream. Normally, QDebug prints the string inside quotes and transforms non-printable characters to their Unicode values (\\u1234). To print non-printable characters without transformation, enable the noquote() functionality. Note that some QDebug backends might not be 8-bit clean. See the QString overload for examples. */ /*! \fn QDebug &QDebug::operator<<(const QByteArray &t) Writes the byte array, \a t, to the stream and returns a reference to the stream. Normally, QDebug prints the array inside quotes and transforms control or non-US-ASCII characters to their C escape sequences (\\xAB). This way, the output is always 7-bit clean and the string can be copied from the output and pasted back into C++ sources, if necessary. To print non-printable characters without transformation, enable the noquote() functionality. Note that some QDebug backends might not be 8-bit clean. Output examples: \snippet code/src_corelib_io_qdebug.cpp 1 Note how QDebug needed to close and reopen the string in the way C and C++ languages concatenate string literals so that the letter 'b' is not interpreted as part of the previous hexadecimal escape sequence. */ /*! \since 6.0 \fn QDebug &QDebug::operator<<(QByteArrayView t) Writes the data of the observed byte array, \a t, to the stream and returns a reference to the stream. Normally, QDebug prints the data inside quotes and transforms control or non-US-ASCII characters to their C escape sequences (\\xAB). This way, the output is always 7-bit clean and the string can be copied from the output and pasted back into C++ sources, if necessary. To print non-printable characters without transformation, enable the noquote() functionality. Note that some QDebug backends might not be 8-bit clean. See the QByteArray overload for examples. */ /*! \fn QDebug &QDebug::operator<<(const void *t) Writes a pointer, \a t, to the stream and returns a reference to the stream. */ /*! \fn QDebug &QDebug::operator<<(QTextStreamFunction f) \internal */ /*! \fn QDebug &QDebug::operator<<(QTextStreamManipulator m) \internal */ /*! \since 6.5 \fn template QDebug &QDebug::operator<<(const std::basic_string &s) \fn template QDebug &QDebug::operator<<(std::basic_string_view s) Writes the string or string-view \a s to the stream and returns a reference to the stream. These operators only participate in overload resolution if \c Char is one of \list \li char \li char8_t (C++20 only) \li char16_t \li char32_t \li wchar_t \endlist */ /*! \since 6.6 \fn template QDebug &QDebug::operator<<(std::chrono::duration duration) Prints the time duration \a duration to the stream and returns a reference to the stream. The printed string is the numeric representation of the period followed by the time unit, similar to what the C++ Standard Library would produce with \c{std::ostream}. The unit is not localized. */ /*! \fn template > QDebug::operator<<(T i) \fn template > QDebug::operator<<(T i) \since 6.7 Prints the textual representation of the 128-bit integer \a i. \note This operator is only available if Qt supports 128-bit integer types. If 128-bit integer types are available in your build, but the Qt libraries were compiled without, the operator will print a warning instead. \note Because the operator is a function template, no implicit conversions are performed on its argument. It must be exactly qint128/quint128. \sa QT_SUPPORTS_INT128 */ /*! \fn template QString QDebug::toString(T &&object) \since 6.0 \include qdebug-toString.qdocinc */ /*! \fn template QDebug operator<<(QDebug debug, const QList &list) \relates QDebug Writes the contents of \a list to \a debug. \c T needs to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const QVarLengthArray &array) \relates QDebug \since 6.3 Writes the contents of \a array to \a debug. \c T needs to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const std::list &vec) \relates QDebug \since 5.7 Writes the contents of list \a vec to \a debug. \c T needs to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const std::vector &vec) \relates QDebug \since 5.7 Writes the contents of vector \a vec to \a debug. \c T needs to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const QSet &set) \relates QDebug Writes the contents of \a set to \a debug. \c T needs to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const QMap &map) \relates QDebug Writes the contents of \a map to \a debug. Both \c Key and \c T need to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const QMultiMap &map) \relates QDebug Writes the contents of \a map to \a debug. Both \c Key and \c T need to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const std::map &map) \relates QDebug \since 5.7 Writes the contents of \a map to \a debug. Both \c Key and \c T need to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const std::multimap &map) \relates QDebug \since 5.7 Writes the contents of \a map to \a debug. Both \c Key and \c T need to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const QHash &hash) \relates QDebug Writes the contents of \a hash to \a debug. Both \c Key and \c T need to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const QMultiHash &hash) \relates QDebug Writes the contents of \a hash to \a debug. Both \c Key and \c T need to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const std::pair &pair) \relates QDebug Writes the contents of \a pair to \a debug. Both \c T1 and \c T2 need to support streaming into QDebug. */ /*! \since 6.7 \fn template QDebug operator<<(QDebug debug, const std::optional &opt) \relates QDebug Writes the contents of \a opt (or \c nullopt if not set) to \a debug. \c T needs to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const QContiguousCache &cache) \relates QDebug Writes the contents of \a cache to \a debug. \c T needs to support streaming into QDebug. */ /*! \fn template QDebug operator<<(QDebug debug, const QFlags &flags) \relates QDebug \since 4.7 Writes \a flags to \a debug. */ /*! \fn template QDebug operator<<(QDebug debug, const QSharedPointer &ptr) \relates QSharedPointer \since 5.7 Writes the pointer tracked by \a ptr into the debug object \a debug for debugging purposes. \sa {Debugging Techniques} */ /*! \fn QDebug &QDebug::operator<<(std::nullptr_t) \internal */ /*! \since 6.7 \fn QDebug &QDebug::operator<<(std::nullopt_t) Writes nullopt to the stream. */ /*! \class QDebugStateSaver \inmodule QtCore \brief Convenience class for custom QDebug operators. Saves the settings used by QDebug, and restores them upon destruction, then calls \l {QDebug::maybeSpace()}{maybeSpace()}, to separate arguments with a space if \l {QDebug::autoInsertSpaces()}{autoInsertSpaces()} was true at the time of constructing the QDebugStateSaver. The automatic insertion of spaces between writes is one of the settings that QDebugStateSaver stores for the duration of the current block. The settings of the internal QTextStream are also saved and restored, so that using << Qt::hex in a QDebug operator doesn't affect other QDebug operators. QDebugStateSaver is typically used in the implementation of an operator<<() for debugging: \snippet customtype/customtypeexample.cpp custom type streaming operator \since 5.1 */ class QDebugStateSaverPrivate { public: QDebugStateSaverPrivate(QDebug::Stream *stream) : m_stream(stream), m_spaces(stream->space), m_noQuotes(stream->noQuotes), m_verbosity(stream->verbosity), m_streamParams(stream->ts.d_ptr->params) { } void restoreState() { const bool currentSpaces = m_stream->space; if (currentSpaces && !m_spaces) if (m_stream->buffer.endsWith(u' ')) m_stream->buffer.chop(1); m_stream->space = m_spaces; m_stream->noQuotes = m_noQuotes; m_stream->ts.d_ptr->params = m_streamParams; m_stream->verbosity = m_verbosity; if (!currentSpaces && m_spaces) m_stream->ts << ' '; } QDebug::Stream *m_stream; // QDebug state const bool m_spaces; const bool m_noQuotes; const int m_verbosity; // QTextStream state const QTextStreamPrivate::Params m_streamParams; }; /*! Creates a QDebugStateSaver instance, which saves the settings currently used by \a dbg. \sa QDebug::setAutoInsertSpaces(), QDebug::autoInsertSpaces() */ QDebugStateSaver::QDebugStateSaver(QDebug &dbg) : d(new QDebugStateSaverPrivate(dbg.stream)) { } /*! Destroys a QDebugStateSaver instance, which restores the settings used when the QDebugStateSaver instance was created. \sa QDebug::setAutoInsertSpaces(), QDebug::autoInsertSpaces() */ QDebugStateSaver::~QDebugStateSaver() { d->restoreState(); } /*! \internal Specialization of the primary template in qdebug.h to out-of-line the common case of QFlags::Int being int. Just call the generic version so the two don't get out of sync. */ void qt_QMetaEnum_flagDebugOperator(QDebug &debug, size_t sizeofT, int value) { qt_QMetaEnum_flagDebugOperator(debug, sizeofT, value); } #ifndef QT_NO_QOBJECT /*! \internal Formats the given enum \a value for debug output. The supported verbosity are: 0: Just the key, or value with enum name if no key is found: MyEnum2 MyEnum(123) MyScopedEnum::Enum3 MyScopedEnum(456) 1: Same as 0, but treating all enums as scoped: MyEnum::MyEnum2 MyEnum(123) MyScopedEnum::Enum3 MyScopedEnum(456) 2: The QDebug default. Same as 0, and includes class/namespace scope: MyNamespace::MyClass::MyEnum2 MyNamespace::MyClass::MyEnum(123) MyNamespace::MyClass::MyScopedEnum::Enum3 MyNamespace::MyClass::MyScopedEnum(456) 3: Same as 2, but treating all enums as scoped: MyNamespace::MyClass::MyEnum::MyEnum2 MyNamespace::MyClass::MyEnum(123) MyNamespace::MyClass::MyScopedEnum::Enum3 MyNamespace::MyClass::MyScopedEnum(456) */ QDebug qt_QMetaEnum_debugOperator(QDebug &dbg, qint64 value, const QMetaObject *meta, const char *name) { QDebugStateSaver saver(dbg); dbg.nospace(); QMetaEnum me = meta->enumerator(meta->indexOfEnumerator(name)); const int verbosity = dbg.verbosity(); if (verbosity >= QDebug::DefaultVerbosity) { if (const char *scope = me.scope()) dbg << scope << u"::"; } const char *key = me.valueToKey(static_cast(value)); const bool scoped = me.isScoped() || verbosity & 1; if (scoped || !key) dbg << me.enumName() << (!key ? u"(" : u"::"); if (key) dbg << key; else dbg << value << ')'; return dbg; } /*! \fn QDebug qt_QMetaEnum_flagDebugOperator(QDebug &, quint64 value, const QMetaObject *, const char *name) \internal Formats the given flag \a value for debug output. The supported verbosity are: 0: Just the key(s): MyFlag1 MyFlag2|MyFlag3 MyScopedFlag(MyFlag2) MyScopedFlag(MyFlag2|MyFlag3) 1: Same as 0, but treating all flags as scoped: MyFlag(MyFlag1) MyFlag(MyFlag2|MyFlag3) MyScopedFlag(MyFlag2) MyScopedFlag(MyFlag2|MyFlag3) 2: The QDebug default. Same as 1, and includes class/namespace scope: QFlags(MyFlag1) QFlags(MyFlag2|MyFlag3) QFlags(MyFlag2) QFlags(MyFlag2|MyFlag3) */ QDebug qt_QMetaEnum_flagDebugOperator(QDebug &debug, quint64 value, const QMetaObject *meta, const char *name) { const int verbosity = debug.verbosity(); QDebugStateSaver saver(debug); debug.resetFormat(); debug.noquote(); debug.nospace(); const QMetaEnum me = meta->enumerator(meta->indexOfEnumerator(name)); const bool classScope = verbosity >= QDebug::DefaultVerbosity; if (classScope) { debug << u"QFlags<"; if (const char *scope = me.scope()) debug << scope << u"::"; } const bool enumScope = me.isScoped() || verbosity > QDebug::MinimumVerbosity; if (enumScope) { debug << me.enumName(); if (classScope) debug << '>'; debug << '('; } debug << me.valueToKeys(static_cast(value)); if (enumScope) debug << ')'; return debug; } #endif // !QT_NO_QOBJECT QT_END_NAMESPACE