source: trunk/src/gui/kernel/qmime_pm.cpp@ 336

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#include "qmime.h"

#include "qimagereader.h"
#include "qimagewriter.h"
#include "qdatastream.h"
#include "qbuffer.h"
#include "qt_os2.h"
#include "qapplication_p.h"
#include "qtextcodec.h"
#include "qregexp.h"
#include "qalgorithms.h"
#include "qmap.h"
#include "qdnd_p.h"
#include "qurl.h"
#include "qvariant.h"
#include "qtextdocument.h"
#include "qdir.h"

#define QMIME_DEBUG

QT_BEGIN_NAMESPACE

class QPMMimeList
{
public:
    QPMMimeList();
    ~QPMMimeList();
    void addMime(QPMMime *mime);
    void removeMime(QPMMime *mime);
    QList<QPMMime*> mimes();

private:
    void init();
    bool initialized;
    QList<QPMMime*> list;
};

Q_GLOBAL_STATIC(QPMMimeList, theMimeList);


/*!
    \class QPMMime
    \brief The QMPMime class maps open-standard MIME to OS/2 PM Clipboard
    formats.
    \ingroup io
    \ingroup draganddrop
    \ingroup misc

    Qt's drag-and-drop and clipboard facilities use the MIME standard.
    On X11, this maps trivially to the Xdnd protocol, but on OS/2
    although some applications use MIME types to describe clipboard
    formats, others use arbitrary non-standardized naming conventions,
    or unnamed built-in formats of the Presentation Manager.

    By instantiating subclasses of QPMMime that provide conversions between OS/2
    PM Clipboard and MIME formats, you can convert proprietary clipboard formats
    to MIME formats.

    Qt has predefined support for the following PM Clipboard formats:

    \table
    \header \o PM Format \o Equivalent MIME type
    \row \o \c CF_TEXT        \o \c text/plain
    \row \o \c CF_BITMAP      \o \c{image/xyz}, where \c xyz is
                                 a \l{QImageWriter::supportedImageFormats()}{Qt image format}
    \endtable

    An example use of this class would be to map the PM Metafile
    clipboard format (\c CF_METAFILE) to and from the MIME type
    \c{image/x-metafile}. This conversion might simply be adding or removing a
    header, or even just passing on the data. See \l{Drag and Drop} for more
    information on choosing and definition MIME types.
*/

/*!
Constructs a new conversion object, adding it to the globally accessed
list of available converters.
*/
QPMMime::QPMMime()
{
    theMimeList()->addMime(this);
}

/*!
Destroys a conversion object, removing it from the global
list of available converters.
*/
QPMMime::~QPMMime()
{
    theMimeList()->removeMime(this);
}

/*!
    Registers the MIME type \a mime, and returns an ID number
    identifying the format on OS/2. Intended to be used by QPMMime
    implementations for registering custom clipboard formats they use.
*/
// static
ULONG QPMMime::registerMimeType(const QString &mime)
{
    ULONG cf = WinAddAtom(WinQuerySystemAtomTable(), mime.toLocal8Bit());
    if (!cf) {
#ifndef QT_NO_DEBUG
        qWarning("QPMMime: WinAddAtom failed with %lX",
                 WinGetLastError(NULLHANDLE));
#endif
        return 0;
    }

    return cf;
}

/*!
    Allocates a block of shared memory of the given size and returns the address
    of this block. This memory block may be then filled with data and returned
    by convertFromMimeData() as the value of the CFI_POINTER type.
*/
// static
ULONG QPMMime::allocateMemory(size_t size)
{
    if (size == 0)
        return 0;

    ULONG data = 0;

    // allocate giveable memory for the array + dword for its size
    APIRET arc = DosAllocSharedMem((PVOID *)&data, NULL, size + 4,
                                   PAG_WRITE  | PAG_COMMIT | OBJ_GIVEABLE);
    if (arc != NO_ERROR) {
#ifndef QT_NO_DEBUG
        qWarning("QPMMime::allocateMemory: DosAllocSharedMem failed with %lu", arc);
#endif
        return 0;
    }

    /// @todo I think we don't need it any more
#if 0
    // get the size rounded to the page boundary (4K)
    ULONG sz = ~0, flags = 0;
    arc = DosQueryMem((PVOID)(data + size - 1), &sz, &flags);
    if (arc != NO_ERROR) {
#ifndef QT_NO_DEBUG
        qWarning("QPMMime::allocateMemory: DosQueryMem failed with %lu", arc);
#endif
        DosFreeMem((PVOID)data);
        return 0;
    }
    sz += (size - 1);