qlibrary.cpp

qt-x11-opensource-src-4.1.4.tar.gz源码

    QStringList suffixes = completeSuffix.split(QLatin1Char('.'));
    QString suffix = suffixes.first();
# if defined(Q_OS_DARWIN)
    
    // On Mac, libs look like libmylib.1.0.0.dylib
    const QString lastSuffix = suffixes.at(suffixes.count() - 1);
    const QString firstSuffix = suffixes.at(0);
        
    bool valid = (lastSuffix == "dylib"
            || firstSuffix == "so"
            || firstSuffix == "bundle");

    return valid;
# elif defined(Q_OS_HPUX)
/*  
    See "HP-UX Linker and Libraries User's Guide", section "Link-time Differences between PA-RISC and IPF":
    "In PA-RISC (PA-32 and PA-64) shared libraries are suffixed with .sl. In IPF (32-bit and 64-bit), 
    the shared libraries are suffixed with .so. For compatibility, the IPF linker also supports the .sl suffix."
 */
    bool valid = (suffix == "sl");
#  if defined __ia64
    valid |= (suffix == "so")
#  endif
# elif defined(Q_OS_UNIX)
    bool valid = (suffix == "so");
# elif defined(Q_OS_AIX)
	bool valid = (suffix == "a"
			|| suffix == "so");
# else
    bool valid = false;
# endif

    for (int i = 1; i < suffixes.count() && valid; ++i)
        suffixes.at(i).toInt(&valid);
    return valid;
#endif

}

bool QLibraryPrivate::isPlugin()
{
    if (pluginState != MightBeAPlugin)
        return pluginState == IsAPlugin;

    if (!QLibrary::isLibrary(fileName))
        return false;

    bool debug = !QLIBRARY_AS_DEBUG;
    QByteArray key;
    bool success = false;

    QFileInfo fileinfo(fileName);

#ifndef QT_NO_DATESTRING
    lastModified  = fileinfo.lastModified().toString(Qt::ISODate);
#endif
    QString regkey = QString::fromLatin1("Qt Plugin Cache %1.%2.%3/%4")
                     .arg((QT_VERSION & 0xff0000) >> 16)
                     .arg((QT_VERSION & 0xff00) >> 8)
                     .arg(QLIBRARY_AS_DEBUG ? "debug" : "false")
                     .arg(fileName);
    QStringList reg;

    QSettings settings(QSettings::UserScope, QLatin1String("Trolltech"));
    reg = settings.value(regkey).toStringList();
    if (reg.count() == 4 && lastModified == reg.at(3)) {
        qt_version = reg.at(0).toUInt(0, 16);
        debug = bool(reg.at(1).toInt());
        key = reg.at(2).toLatin1();
        success = qt_version != 0;
    } else {
#if defined(Q_OS_UNIX)
        if (!pHnd) {
            // use unix shortcut to avoid loading the library
            success = qt_unix_query(fileName, &qt_version, &debug, &key);
        } else
#endif
        {
            bool temporary_load = false;
            if (!pHnd)
                temporary_load =  load_sys();
#  ifdef Q_CC_BOR
            typedef const char * __stdcall (*QtPluginQueryVerificationDataFunction)();
#  else
            typedef const char * (*QtPluginQueryVerificationDataFunction)();
#  endif
            QtPluginQueryVerificationDataFunction qtPluginQueryVerificationDataFunction =
                (QtPluginQueryVerificationDataFunction) resolve("qt_plugin_query_verification_data");

            if (!qtPluginQueryVerificationDataFunction
                || !qt_parse_pattern(qtPluginQueryVerificationDataFunction(), &qt_version, &debug, &key)) {
                qt_version = 0;
                key = "unknown";
                if (temporary_load)
                    unload_sys();
            } else {
                success = true;
            }
        }

        QStringList queried;
        queried << QString::number(qt_version,16)
                << QString::number((int)debug)
                << QLatin1String(key)
                << lastModified;
        settings.setValue(regkey, queried);
    }

    if (!success)
        return false;

    pluginState = IsNotAPlugin; // be pessimistic

    if ((qt_version > QT_VERSION) || ((QT_VERSION & 0xff0000) > (qt_version & 0xff0000))) {
#if defined(QT_DEBUG_COMPONENT)
        qWarning("In %s:\n"
                 "  Plugin uses incompatible Qt library (%d.%d.%d) [%s]",
                 (const char*) QFile::encodeName(fileName),
                 (qt_version&0xff0000) >> 16, (qt_version&0xff00) >> 8, qt_version&0xff,
                 debug ? "debug" : "release");
#endif
    } else if (key != QT_BUILD_KEY) {
#if defined(QT_DEBUG_COMPONENT)
        qWarning("In %s:\n"
                 "  Plugin uses incompatible Qt library\n"
                 "  expected build key \"%s\", got \"%s\"",
                 (const char*) QFile::encodeName(fileName),
                 QT_BUILD_KEY,
                 key.isEmpty() ? "<null>" : (const char *) key);
#endif
#ifndef QT_NO_DEBUG_PLUGIN_CHECK
    } else if(debug != QLIBRARY_AS_DEBUG) {
        //don't issue a qWarning since we will hopefully find a non-debug? --Sam
#endif
    } else {
        pluginState = IsAPlugin;
    }

    return pluginState == IsAPlugin;
}

/*!
    Loads the library and returns true if the library was loaded
    successfully; otherwise returns false. Since resolve() always
    calls this function before resolving any symbols it is not
    necessary to call it explicitly. In some situations you might want
    the library loaded in advance, in which case you would use this
    function.

    On Mac OS X this function uses code from dlcompat, part of the
    OpenDarwin project.

    \sa unload()

    \legalese
    Copyright (c) 2002 Jorge Acereda and Peter O'Gorman.

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
    LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
    OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
bool QLibrary::load()
{
    if (!d)
        return false;
    if (did_load)
        return d->pHnd;
    did_load = true;
    return d->load();
}

/*!
    Unloads the library and returns true if the library could be
    unloaded; otherwise returns false.

    This happens automatically on application termination, so you
    shouldn't normally need to call this function.

    If other instances of QLibrary are using the same library, the
    call will fail, and unloading will only happen when every instance
    has called unload().

    Note that on Mac OS X, dynamic libraries cannot be unloaded.

    \sa resolve(), load()
*/
bool QLibrary::unload()
{
    if (did_load) {
        did_load = false;
        return d->unload();
    }
    return false;
}

/*!
    Returns true if the library is loaded; otherwise returns false.

    \sa load()
 */
bool QLibrary::isLoaded() const
{
    return d && d->pHnd;
}


/*!
    Constructs a library with the given \a parent.
 */
QLibrary::QLibrary(QObject *parent)
    :QObject(parent), d(0), did_load(false)
{
}


/*!
    Constructs a library object with the given \a parent that will
    load the library specified by \a fileName.

    We recommend omitting the file's suffix in \a fileName, since
    QLibrary will automatically look for the file with the appropriate
    suffix in accordance with the platform, e.g. ".so" on Unix,
    ".dylib" on Mac OS X, and ".dll" on Windows. (See \l{fileName}.)
 */
QLibrary::QLibrary(const QString& fileName, QObject *parent)
    :QObject(parent), d(0), did_load(false)
{
    setFileName(fileName);
}


/*!
    Constructs a library object with the given \a parent that will
    load the library specified by \a fileName and major version number \a verNum.

    We recommend omitting the file's suffix in \a fileName, since
    QLibrary will automatically look for the file with the appropriate
    suffix in accordance with the platform, e.g. ".so" on Unix,
    ".dylib" on Mac OS X, and ".dll" on Windows. (See \l{fileName}.)
 */
QLibrary::QLibrary(const QString& fileName, int verNum, QObject *parent)
    :QObject(parent), d(0), did_load(false)
{
    setFileNameAndVersion(fileName, verNum);
}

/*!
    Destroys the QLibrary object.

    Unless unload() was called explicitly, the library stays in memory
    until the application terminates.

    \sa isLoaded(), unload()
*/
QLibrary::~QLibrary()
{
    if (d)
        d->release();
}


/*!
    \property QLibrary::fileName
    \brief the file name of the library

    We recommend omitting the file's suffix in the file name, since
    QLibrary will automatically look for the file with the appropriate
    suffix (see isLibrary()).

    When loading the library, QLibrary searches in all system-specific
    library locations (e.g. \c LD_LIBRARY_PATH on Unix), unless the
    file name has an absolute path. After loading the library
    successfully, fileName() returns the fully qualified file name of
    the library. For example, after successfully loading the "GL"
    library on unix, fileName() will return "libGL.so".
*/

void QLibrary::setFileName(const QString &fileName)
{
    if (d) {
        d->release();
        d = 0;
        did_load = false;
    }
    d = QLibraryPrivate::findOrCreate(fileName);
    if (d && d->pHnd)
        did_load = true;

}

QString QLibrary::fileName() const
{
    if (d)
        return d->qualifiedFileName.isEmpty() ? d->fileName : d->qualifiedFileName;
    return QString();
}

/*!
    \fn void QLibrary::setFileNameAndVersion(const QString &fileName, int versionNumber)

    Sets the fileName property and major version number to \a fileName
    and \a versionNumber respectively.

    \sa setFileName()
*/
void QLibrary::setFileNameAndVersion(const QString &fileName, int verNum)
{
    if (d) {
        d->release();
        d = 0;
        did_load = false;
    }
    d = QLibraryPrivate::findOrCreate(fileName, verNum);
    if (d && d->pHnd)
        did_load = true;
}

/*!
    Returns the address of the exported symbol \a symbol. The library is
    loaded if necessary. The function returns 0 if the symbol could
    not be resolved or if the library could not be loaded.

    Example:
    \code
        typedef int (*AvgFunction)(int, int);

        AvgFunction avg = (AvgFunction) library->resolve("avg");
        if (avg)
            return avg(5, 8);
        else
            return -1;
    \endcode

    The symbol must be exported as a C function from the library. This
    means that the function must be wrapped in an \c{extern "C"} if
    the library is compiled with a C++ compiler. On Windows you must
    also explicitly export the function from the DLL using the
    \c{__declspec(dllexport)} compiler directive, for example:

    \code
        extern "C" MY_EXPORT int avg(int a, int b)
        {
            return (a + b) / 2;
        }
    \endcode

    with \c MY_EXPORT defined as

    \code
        #ifdef Q_WS_WIN
        #define MY_EXPORT __declspec(dllexport)
        #else
        #define MY_EXPORT
        #endif
    \endcode

    On Mac OS X this function uses code from dlcompat, part of the
    OpenDarwin project.

    \legalese
    Copyright (c) 2002 Jorge Acereda and Peter O'Gorman.

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
    LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
    OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
void *QLibrary::resolve(const char *symbol)
{
    if (!d)
        return 0;
    if (!d->pHnd)
        d->load();
    return d->resolve(symbol);
}

/*!
    \overload

    Loads the library \a fileName and returns the address of the
    exported symbol \a symbol. Note that \a fileName should not
    include the platform-specific file suffix; (see \l{fileName}). The
    library remains loaded until the application exits.

    The function returns 0 if the symbol could not be resolved or if
    the library could not be loaded.

    \sa resolve()
*/
void *QLibrary::resolve(const QString &fileName, const char *symbol)
{
    QLibrary library(fileName);
    return library.resolve(symbol);
}

/*!
    \overload

    Loads the library \a fileName with major version number \a verNum and
    returns the address of the exported symbol \a symbol.
    Note that \a fileName should not include the platform-specific file suffix;
    (see \l{fileName}). The library remains loaded until the application exits.

    The function returns 0 if the symbol could not be resolved or if
    the library could not be loaded.

    \sa resolve()
*/
void *QLibrary::resolve(const QString &fileName, int verNum, const char *symbol)
{
    QLibrary library(fileName, verNum);
    return library.resolve(symbol);
}

/*!
    \fn QString QLibrary::library() const

    Use fileName() instead.
*/

/*!
    \fn void QLibrary::setAutoUnload( bool b )

    Use load(), isLoaded(), and unload() as necessary instead.
*/

#endif // QT_NO_LIBRARY