static void readGPOSTable(SFFontRef sfFont) {
CFDataRef gposTable = CGFontCopyTableForTag(sfFont->_cgFont, 'GPOS');
if (gposTable) {
const SFUByte * const tableBytes = CFDataGetBytePtr(gposTable);
SFReadGPOS(tableBytes, &sfFont->_gpos);
sfFont->_availableFontTables |= itGPOS;
CFRelease(gposTable);
}
}
static void readGSUBTable(SFFontRef sfFont) {
CFDataRef gsubTable = CGFontCopyTableForTag(sfFont->_cgFont, 'GSUB');
if (gsubTable) {
const SFUByte * const tableBytes = CFDataGetBytePtr(gsubTable);
SFReadGSUB(tableBytes, &sfFont->_gsub);
sfFont->_availableFontTables |= itGSUB;
CFRelease(gsubTable);
}
}
static void readGDEFTable(SFFontRef sfFont) {
CFDataRef gdefData = CGFontCopyTableForTag(sfFont->_cgFont, 'GDEF');
if (gdefData) {
const SFUByte * const tableBytes = CFDataGetBytePtr(gdefData);
SFReadGDEF(tableBytes, &sfFont->_gdef);
sfFont->_availableFontTables |= itGDEF;
CFRelease(gdefData);
}
}
static void readCMAPTable(SFFontRef sfFont) {
CFDataRef cmapData = CGFontCopyTableForTag(sfFont->_cgFont, 'cmap');
if (cmapData) {
const SFUByte * const tableBytes = CFDataGetBytePtr(cmapData);
SFReadCMAP(tableBytes, &sfFont->_cmap, CFDataGetLength(cmapData));
sfFont->_availableFontTables |= itCMAP;
CFRelease(cmapData);
}
}
static hb_blob_t* harfBuzzCoreTextGetTable(hb_face_t* face, hb_tag_t tag, void* userData)
{
CGFontRef cgFont = reinterpret_cast<CGFontRef>(userData);
CFDataRef cfData = CGFontCopyTableForTag(cgFont, tag);
if (!cfData)
return 0;
const char* data = reinterpret_cast<const char*>(CFDataGetBytePtr(cfData));
const size_t length = CFDataGetLength(cfData);
if (!data || !length)
return 0;
return hb_blob_create(data, length, HB_MEMORY_MODE_READONLY, reinterpret_cast<void*>(const_cast<__CFData*>(cfData)), releaseTableData);
}
bool
ScaledFontMac::GetFontFileData(FontFileDataOutput aDataCallback, void *aBaton)
{
// We'll reconstruct a TTF font from the tables we can get from the CGFont
CFArrayRef tags = CGFontCopyTableTags(mFont);
CFIndex count = CFArrayGetCount(tags);
TableRecord *records = new TableRecord[count];
uint32_t offset = 0;
offset += sizeof(uint32_t)*3;
offset += sizeof(uint32_t)*4*count;
bool CFF = false;
for (CFIndex i = 0; i<count; i++) {
uint32_t tag = (uint32_t)(uintptr_t)CFArrayGetValueAtIndex(tags, i);
if (tag == 0x43464620) // 'CFF '
CFF = true;
CFDataRef data = CGFontCopyTableForTag(mFont, tag);
records[i].tag = tag;
records[i].offset = offset;
records[i].data = data;
records[i].length = CFDataGetLength(data);
bool skipChecksumAdjust = (tag == 0x68656164); // 'head'
records[i].checkSum = CalcTableChecksum(reinterpret_cast<const uint32_t*>(CFDataGetBytePtr(data)),
records[i].length, skipChecksumAdjust);
offset += records[i].length;
// 32 bit align the tables
offset = (offset + 3) & ~3;
}
CFRelease(tags);
struct writeBuf buf(offset);
// write header/offset table
if (CFF) {
buf.writeElement(CFSwapInt32HostToBig(0x4f54544f));
} else {
buf.writeElement(CFSwapInt32HostToBig(0x00010000));
}
buf.writeElement(CFSwapInt16HostToBig(count));
buf.writeElement(CFSwapInt16HostToBig((1<<maxPow2LessThan(count))*16));
buf.writeElement(CFSwapInt16HostToBig(maxPow2LessThan(count)));
buf.writeElement(CFSwapInt16HostToBig(count*16-((1<<maxPow2LessThan(count))*16)));
// write table record entries
for (CFIndex i = 0; i<count; i++) {
buf.writeElement(CFSwapInt32HostToBig(records[i].tag));
buf.writeElement(CFSwapInt32HostToBig(records[i].checkSum));
buf.writeElement(CFSwapInt32HostToBig(records[i].offset));
buf.writeElement(CFSwapInt32HostToBig(records[i].length));
}
// write tables
int checkSumAdjustmentOffset = 0;
for (CFIndex i = 0; i<count; i++) {
if (records[i].tag == 0x68656164) {
checkSumAdjustmentOffset = buf.offset + 2*4;
}
buf.writeMem(CFDataGetBytePtr(records[i].data), CFDataGetLength(records[i].data));
buf.align();
CFRelease(records[i].data);
}
delete[] records;
// clear the checksumAdjust field before checksumming the whole font
memset(&buf.data[checkSumAdjustmentOffset], 0, sizeof(uint32_t));
uint32_t fontChecksum = CFSwapInt32HostToBig(0xb1b0afba - CalcTableChecksum(reinterpret_cast<const uint32_t*>(buf.data), offset));
// set checkSumAdjust to the computed checksum
memcpy(&buf.data[checkSumAdjustmentOffset], &fontChecksum, sizeof(fontChecksum));
// we always use an index of 0
aDataCallback(buf.data, buf.offset, 0, mSize, aBaton);
return true;
}
