qlibrary_win.cpp

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#include "qplatformdefs.h"
#include "qlibrary_p.h"
#include "qfile.h"
#include "qdir.h"
#include "qfileinfo.h"
#include "qdir.h"
#include <private/qfilesystementry_p.h>

#if defined(QT_NO_LIBRARY) && defined(Q_OS_WIN)
#undef QT_NO_LIBRARY
#pragma message("QT_NO_LIBRARY is not supported on Windows")
#endif

#include "qt_windows.h"

QT_BEGIN_NAMESPACE

extern QString qt_error_string(int code);

bool QLibraryPrivate::load_sys()
{
    //avoid 'Bad Image' message box
    UINT oldmode = SetErrorMode(SEM_FAILCRITICALERRORS|SEM_NOOPENFILEERRORBOX);

    // We make the following attempts at locating the library:
    //
    // WinCE
    // if (loadHints & QLibrary::ImprovedSearchHeuristics)
    //   if (absolute)
    //     fileName
    //     fileName + ".dll"
    //   else
    //     fileName + ".dll"
    //     fileName
    //     QFileInfo(fileName).absoluteFilePath()
    // else
    //   QFileInfo(fileName).absoluteFilePath();
    //   fileName
    //   fileName + ".dll"
    //
    // Windows
    // if (loadHints & QLibrary::ImprovedSearchHeuristics)
    //   if (absolute)
    //     fileName
    //     fileName + ".dll"
    //   else
    //     fileName + ".dll"
    //     fileName
    // else
    //   fileName
    //   fileName + ".dll"
    //
    // NB If it's a plugin we do not ever try the ".dll" extension
    QStringList attempts;
    QFileSystemEntry fsEntry(fileName);
    if (loadHints & QLibrary::ImprovedSearchHeuristics) {
        if (pluginState != IsAPlugin)
            attempts.append(fileName + QLatin1String(".dll"));

        // If the fileName is an absolute path we try that first, otherwise we
        // use the system-specific suffix first
        if (fsEntry.isAbsolute()) {
            attempts.prepend(fileName);
        } else {
            attempts.append(fileName);
#if defined(Q_OS_WINCE)
            attempts.append(QFileInfo(fileName).absoluteFilePath());
#endif
        }
    } else {
#ifdef Q_OS_WINCE
        attempts.append(QFileInfo(fileName).absoluteFilePath());
#else
        attempts.append(fileName);
#endif
        if (pluginState != IsAPlugin) {
#if defined(Q_OS_WINCE)
            attempts.append(fileName);
#endif
            attempts.append(fileName + QLatin1String(".dll"));
        }
    }

    Q_FOREACH (const QString &attempt, attempts) {
        pHnd = LoadLibrary((wchar_t*)QDir::toNativeSeparators(attempt).utf16());

        // If we have a handle or the last error is something other than "unable
        // to find the module", then bail out
        if (pHnd || ::GetLastError() != ERROR_MOD_NOT_FOUND)
            break;
    }

    SetErrorMode(oldmode);
    if (!pHnd) {
        errorString = QLibrary::tr("Cannot load library %1: %2").arg(fileName).arg(qt_error_string());
    } else {
        // Query the actual name of the library that was loaded
        errorString.clear();

        wchar_t buffer[MAX_PATH];
        ::GetModuleFileName(pHnd, buffer, MAX_PATH);

        QString moduleFileName = QString::fromWCharArray(buffer);
        moduleFileName.remove(0, 1 + moduleFileName.lastIndexOf(QLatin1Char('\\')));
        const QDir dir(fsEntry.path());
        if (dir.path() == QLatin1String("."))
            qualifiedFileName = moduleFileName;
        else
            qualifiedFileName = dir.filePath(moduleFileName);
    }
    return (pHnd != 0);
}

bool QLibraryPrivate::unload_sys()
{
    if (!FreeLibrary(pHnd)) {
        errorString = QLibrary::tr("Cannot unload library %1: %2").arg(fileName).arg(qt_error_string());
        return false;
    }
    errorString.clear();
    return true;
}

void* QLibraryPrivate::resolve_sys(const char* symbol)
{
#ifdef Q_OS_WINCE
    void* address = (void*)GetProcAddress(pHnd, (const wchar_t*)QString::fromLatin1(symbol).utf16());
#else
    void* address = (void*)GetProcAddress(pHnd, symbol);
#endif
    if (!address) {
        errorString = QLibrary::tr("Cannot resolve symbol \"%1\" in %2: %3").arg(
            QString::fromAscii(symbol)).arg(fileName).arg(qt_error_string());
    } else {
        errorString.clear();
    }
    return address;
}
QT_END_NAMESPACE