/*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Author(s): Behdad Esfahbod
*/
#ifndef HB_DIRECTWRITE_HH
#define HB_DIRECTWRITE_HH
#include "hb.hh"
#include "hb-directwrite.h"
#include "hb-mutex.hh"
#include "hb-map.hh"
/*
* DirectWrite font stream helpers
*/
// Have a look at to NativeFontResourceDWrite.cpp in Mozilla
/* Declare object creator for dynamic support of DWRITE */
typedef HRESULT (WINAPI *t_DWriteCreateFactory)(
DWRITE_FACTORY_TYPE factoryType,
REFIID iid,
IUnknown **factory
);
class DWriteFontFileLoader : public IDWriteFontFileLoader
{
private:
hb_reference_count_t mRefCount;
hb_mutex_t mutex;
hb_hashmap_t<uint64_t, IDWriteFontFileStream *> mFontStreams;
uint64_t mNextFontFileKey = 0;
public:
DWriteFontFileLoader ()
{
mRefCount.init ();
}
uint64_t RegisterFontFileStream (IDWriteFontFileStream *fontFileStream)
{
fontFileStream->AddRef ();
hb_lock_t lock {mutex};
mFontStreams.set (mNextFontFileKey, fontFileStream);
return mNextFontFileKey++;
}
void UnregisterFontFileStream (uint64_t fontFileKey)
{
hb_lock_t lock {mutex};
IDWriteFontFileStream *stream = mFontStreams.get (fontFileKey);
if (stream)
{
mFontStreams.del (fontFileKey);
stream->Release ();
}
}
// IUnknown interface
IFACEMETHOD (QueryInterface) (IID const& iid, OUT void** ppObject)
{ return S_OK; }
IFACEMETHOD_ (ULONG, AddRef) ()
{
return mRefCount.inc () + 1;
}
IFACEMETHOD_ (ULONG, Release) ()
{
signed refCount = mRefCount.dec () - 1;
assert (refCount >= 0);
if (refCount)
return refCount;
delete this;
return 0;
}
// IDWriteFontFileLoader methods
virtual HRESULT STDMETHODCALLTYPE
CreateStreamFromKey (void const* fontFileReferenceKey,
uint32_t fontFileReferenceKeySize,
OUT IDWriteFontFileStream** fontFileStream)
{
if (fontFileReferenceKeySize != sizeof (uint64_t))
return E_INVALIDARG;
uint64_t fontFileKey = * (uint64_t *) fontFileReferenceKey;
IDWriteFontFileStream *stream = mFontStreams.get (fontFileKey);
if (!stream)
return E_FAIL;
stream->AddRef ();
*fontFileStream = stream;
return S_OK;
}
virtual ~DWriteFontFileLoader()
{
for (auto v : mFontStreams.values ())
v->Release ();
}
};
class DWriteFontFileStream : public IDWriteFontFileStream
{
private:
hb_reference_count_t mRefCount;
hb_blob_t *mBlob;
uint8_t *mData;
unsigned mSize;
DWriteFontFileLoader *mLoader;
public:
uint64_t fontFileKey;
public:
DWriteFontFileStream (hb_blob_t *blob);
// IUnknown interface
IFACEMETHOD (QueryInterface) (IID const& iid, OUT void** ppObject)
{ return S_OK; }
IFACEMETHOD_ (ULONG, AddRef) ()
{
return mRefCount.inc () + 1;
}
IFACEMETHOD_ (ULONG, Release) ()
{
signed refCount = mRefCount.dec () - 1;
assert (refCount >= 0);
if (refCount)
return refCount;
delete this;
return 0;
}
// IDWriteFontFileStream methods
virtual HRESULT STDMETHODCALLTYPE
ReadFileFragment (void const** fragmentStart,
UINT64 fileOffset,
UINT64 fragmentSize,
OUT void** fragmentContext)
{
// We are required to do bounds checking.
if (fileOffset + fragmentSize > mSize) return E_FAIL;
// truncate the 64 bit fileOffset to size_t sized index into mData
size_t index = static_cast<size_t> (fileOffset);
// We should be alive for the duration of this.
*fragmentStart = &mData[index];
*fragmentContext = nullptr;
return S_OK;
}
virtual void STDMETHODCALLTYPE
ReleaseFileFragment (void* fragmentContext) {}
virtual HRESULT STDMETHODCALLTYPE
GetFileSize (OUT UINT64* fileSize)
{
*fileSize = mSize;
return S_OK;
}
virtual HRESULT STDMETHODCALLTYPE
GetLastWriteTime (OUT UINT64* lastWriteTime) { return E_NOTIMPL; }
virtual ~DWriteFontFileStream();
};
struct hb_directwrite_global_t
{
hb_directwrite_global_t ()
{
HRESULT hr = DWriteCreateFactory (DWRITE_FACTORY_TYPE_SHARED, __uuidof (IDWriteFactory),
(IUnknown**) &dwriteFactory);
if (unlikely (hr != S_OK))
return;
fontFileLoader = new DWriteFontFileLoader ();
dwriteFactory->RegisterFontFileLoader (fontFileLoader);
success = true;
}
~hb_directwrite_global_t ()
{
if (fontFileLoader)
fontFileLoader->Release ();
if (dwriteFactory)
dwriteFactory->Release ();
}
bool success = false;
IDWriteFactory *dwriteFactory;
DWriteFontFileLoader *fontFileLoader;
};
HB_INTERNAL hb_directwrite_global_t *
get_directwrite_global ();
HB_INTERNAL IDWriteFontFace *
dw_face_create (hb_blob_t *blob, unsigned index);
#endif /* HB_DIRECTWRITE_HH */
