/** Return the number of tables, or if this is a TTC (collection), return the
number of tables in the first element of the collection. In either case,
if offsetToDir is not-null, set it to the offset to the beginning of the
table headers (SkSFNTDirEntry), relative to the start of the stream.
On an error, return 0 for number of tables, and ignore offsetToDir
*/
static int count_tables(SkStream* stream, size_t* offsetToDir = NULL) {
SkSharedTTHeader shared;
if (stream->read(&shared, sizeof(shared)) != sizeof(shared)) {
return 0;
}
// by default, SkSFNTHeader is at the start of the stream
size_t offset = 0;
// if we're really a collection, the first 4-bytes will be 'ttcf'
uint32_t tag = SkEndian_SwapBE32(shared.fCollection.fTag);
if (SkSetFourByteTag('t', 't', 'c', 'f') == tag) {
if (shared.fCollection.fNumOffsets == 0) {
return 0;
}
// this is the offset to the first local SkSFNTHeader
offset = SkEndian_SwapBE32(shared.fCollection.fOffset0);
stream->rewind();
if (stream->skip(offset) != offset) {
return 0;
}
if (stream->read(&shared, sizeof(shared)) != sizeof(shared)) {
return 0;
}
}
if (offsetToDir) {
// add the size of the header, so we will point to the DirEntries
*offsetToDir = offset + sizeof(SkSFNTHeader);
}
return SkEndian_SwapBE16(shared.fSingle.fNumTables);
}
bool SkHeifCodec::IsHeif(const void* buffer, size_t bytesRead) {
// Parse the ftyp box up to bytesRead to determine if this is HEIF.
// Any valid ftyp box should have at least 8 bytes.
if (bytesRead < 8) {
return false;
}
uint32_t* ptr = (uint32_t*)buffer;
uint64_t chunkSize = SkEndian_SwapBE32(ptr[0]);
uint32_t chunkType = SkEndian_SwapBE32(ptr[1]);
if (chunkType != FOURCC('f', 't', 'y', 'p')) {
return false;
}
int64_t offset = 8;
if (chunkSize == 1) {
// This indicates that the next 8 bytes represent the chunk size,
// and chunk data comes after that.
if (bytesRead < 16) {
return false;
}
auto* chunkSizePtr = SkTAddOffset<const uint64_t>(buffer, offset);
chunkSize = SkEndian_SwapBE64(*chunkSizePtr);
if (chunkSize < 16) {
// The smallest valid chunk is 16 bytes long in this case.
return false;
}
offset += 8;
} else if (chunkSize < 8) {
// The smallest valid chunk is 8 bytes long.
return false;
}
if (chunkSize > bytesRead) {
chunkSize = bytesRead;
}
int64_t chunkDataSize = chunkSize - offset;
// It should at least have major brand (4-byte) and minor version (4-bytes).
// The rest of the chunk (if any) is a list of (4-byte) compatible brands.
if (chunkDataSize < 8) {
return false;
}
uint32_t numCompatibleBrands = (chunkDataSize - 8) / 4;
for (size_t i = 0; i < numCompatibleBrands + 2; ++i) {
if (i == 1) {
// Skip this index, it refers to the minorVersion,
// not a brand.
continue;
}
auto* brandPtr = SkTAddOffset<const uint32_t>(buffer, offset + 4 * i);
uint32_t brand = SkEndian_SwapBE32(*brandPtr);
if (brand == FOURCC('m', 'i', 'f', '1') || brand == FOURCC('h', 'e', 'i', 'c')
|| brand == FOURCC('m', 's', 'f', '1') || brand == FOURCC('h', 'e', 'v', 'c')) {
return true;
}
}
return false;
}
int SkFontStream::CountTTCEntries(SkStream* stream) {
stream->rewind();
SkSharedTTHeader shared;
if (!read(stream, &shared, sizeof(shared))) {
return 0;
}
// if we're really a collection, the first 4-bytes will be 'ttcf'
uint32_t tag = SkEndian_SwapBE32(shared.fCollection.fTag);
if (SkSetFourByteTag('t', 't', 'c', 'f') == tag) {
return SkEndian_SwapBE32(shared.fCollection.fNumOffsets);
} else {
return 1; // normal 'sfnt' has 1 dir entry
}
}
/** Return the number of tables, or if this is a TTC (collection), return the
number of tables in the first element of the collection. In either case,
if offsetToDir is not-null, set it to the offset to the beginning of the
table headers (SkSFNTDirEntry), relative to the start of the stream.
On an error, return 0 for number of tables, and ignore offsetToDir
*/
static int count_tables(SkStream* stream, int ttcIndex, size_t* offsetToDir) {
SkASSERT(ttcIndex >= 0);
SkAutoSMalloc<1024> storage(sizeof(SkSharedTTHeader));
SkSharedTTHeader* header = (SkSharedTTHeader*)storage.get();
if (!read(stream, header, sizeof(SkSharedTTHeader))) {
return 0;
}
// by default, SkSFNTHeader is at the start of the stream
size_t offset = 0;
// if we're really a collection, the first 4-bytes will be 'ttcf'
uint32_t tag = SkEndian_SwapBE32(header->fCollection.fTag);
if (SkSetFourByteTag('t', 't', 'c', 'f') == tag) {
unsigned count = SkEndian_SwapBE32(header->fCollection.fNumOffsets);
if ((unsigned)ttcIndex >= count) {
return 0;
}
if (ttcIndex > 0) { // need to read more of the shared header
stream->rewind();
size_t amount = sizeof(SkSharedTTHeader) + ttcIndex * sizeof(uint32_t);
header = (SkSharedTTHeader*)storage.reset(amount);
if (!read(stream, header, amount)) {
return 0;
}
}
// this is the offset to the local SkSFNTHeader
offset = SkEndian_SwapBE32((&header->fCollection.fOffset0)[ttcIndex]);
stream->rewind();
if (!skip(stream, offset)) {
return 0;
}
if (!read(stream, header, sizeof(SkSFNTHeader))) {
return 0;
}
}
if (offsetToDir) {
// add the size of the header, so we will point to the DirEntries
*offsetToDir = offset + sizeof(SkSFNTHeader);
}
return SkEndian_SwapBE16(header->fSingle.fNumTables);
}
uint32_t SkOTUtils::CalcTableChecksum(SK_OT_ULONG *data, size_t length) {
uint32_t sum = 0;
SK_OT_ULONG *dataEnd = data + ((length + 3) & ~3) / sizeof(SK_OT_ULONG);
for (; data < dataEnd; ++data) {
sum += SkEndian_SwapBE32(*data);
}
return sum;
}
size_t SkFontHost::GetTableData(SkFontID fontID, SkFontTableTag tag,
size_t offset, size_t length, void* data) {
SkStream* stream = SkFontHost::OpenStream(fontID);
if (NULL == stream) {
return 0;
}
SkAutoUnref au(stream);
SfntHeader header;
if (!header.init(stream)) {
return 0;
}
for (int i = 0; i < header.fCount; i++) {
if (SkEndian_SwapBE32(header.fDir[i].fTag) == tag) {
size_t realOffset = SkEndian_SwapBE32(header.fDir[i].fOffset);
size_t realLength = SkEndian_SwapBE32(header.fDir[i].fLength);
// now sanity check the caller's offset/length
if (offset >= realLength) {
return 0;
}
// if the caller is trusting the length from the file, then a
// hostile file might choose a value which would overflow offset +
// length.
if (offset + length < offset) {
return 0;
}
if (offset + length > realLength) {
length = realLength - offset;
}
// skip the stream to the part of the table we want to copy from
stream->rewind();
size_t bytesToSkip = realOffset + offset;
if (stream->skip(bytesToSkip) != bytesToSkip) {
return 0;
}
if (stream->read(data, length) != length) {
return 0;
}
return length;
}
}
return 0;
}
size_t SkFontHost::GetTableSize(SkFontID fontID, SkFontTableTag tag) {
SkStream* stream = SkFontHost::OpenStream(fontID);
if (NULL == stream) {
return 0;
}
SkAutoUnref au(stream);
SfntHeader header;
if (!header.init(stream)) {
return 0;
}
for (int i = 0; i < header.fCount; i++) {
if (SkEndian_SwapBE32(header.fDir[i].fTag) == tag) {
return SkEndian_SwapBE32(header.fDir[i].fLength);
}
}
return 0;
}
static void TypefaceStyle_test(skiatest::Reporter* reporter,
uint16_t weight, uint16_t width, SkData* data)
{
sk_sp<SkData> dataCopy;
SkData* dataToUse = data;
if (!dataToUse->unique()) {
dataCopy = SkData::MakeWithCopy(data->data(), data->size());
dataToUse = dataCopy.get();
}
SkSFNTHeader* sfntHeader = static_cast<SkSFNTHeader*>(dataToUse->writable_data());
SkSFNTHeader::TableDirectoryEntry* tableEntry =
SkTAfter<SkSFNTHeader::TableDirectoryEntry>(sfntHeader);
SkSFNTHeader::TableDirectoryEntry* os2TableEntry = nullptr;
int numTables = SkEndian_SwapBE16(sfntHeader->numTables);
for (int tableEntryIndex = 0; tableEntryIndex < numTables; ++tableEntryIndex) {
if (SkOTTableOS2::TAG == tableEntry[tableEntryIndex].tag) {
os2TableEntry = tableEntry + tableEntryIndex;
break;
}
}
SkASSERT_RELEASE(os2TableEntry);
size_t os2TableOffset = SkEndian_SwapBE32(os2TableEntry->offset);
SkOTTableOS2_V0* os2Table = SkTAddOffset<SkOTTableOS2_V0>(sfntHeader, os2TableOffset);
os2Table->usWeightClass.value = SkEndian_SwapBE16(weight);
using WidthType = SkOTTableOS2_V0::WidthClass::Value;
os2Table->usWidthClass.value = static_cast<WidthType>(SkEndian_SwapBE16(width));
sk_sp<SkTypeface> newTypeface(SkTypeface::MakeFromStream(new SkMemoryStream(dataToUse)));
SkASSERT_RELEASE(newTypeface);
SkFontStyle newStyle = newTypeface->fontStyle();
//printf("%d, %f\n", weight, (newStyle.weight() - (float)0x7FFF) / (float)0x7FFF);
//printf("%d, %f\n", width , (newStyle.width() - (float)0x7F) / (float)0x7F);
//printf("%d, %d\n", weight, newStyle.weight());
//printf("%d, %d\n", width , newStyle.width());
// Some back-ends (CG, GDI, DW) support OS/2 version A which uses 0 - 10 (but all differently).
REPORTER_ASSERT(reporter,
newStyle.weight() == weight ||
(weight <= 10 && newStyle.weight() == 100 * weight) ||
(weight == 4 && newStyle.weight() == 350) || // GDI weirdness
(weight == 5 && newStyle.weight() == 400) || // GDI weirdness
(weight == 0 && newStyle.weight() == 1) || // DW weirdness
(weight == 1000 && newStyle.weight() == 999) // DW weirdness
);
// Some back-ends (GDI) don't support width, ensure these always report 'medium'.
REPORTER_ASSERT(reporter,
newStyle.width() == width ||
newStyle.width() == 5);
}
size_t SkFontStream::GetTableData(SkStream* stream, int ttcIndex,
SkFontTableTag tag,
size_t offset, size_t length, void* data) {
SfntHeader header;
if (!header.init(stream, ttcIndex)) {
return 0;
}
for (int i = 0; i < header.fCount; i++) {
if (SkEndian_SwapBE32(header.fDir[i].fTag) == tag) {
size_t realOffset = SkEndian_SwapBE32(header.fDir[i].fOffset);
size_t realLength = SkEndian_SwapBE32(header.fDir[i].fLength);
// now sanity check the caller's offset/length
if (offset >= realLength) {
return 0;
}
// if the caller is trusting the length from the file, then a
// hostile file might choose a value which would overflow offset +
// length.
if (offset + length < offset) {
return 0;
}
if (length > realLength - offset) {
length = realLength - offset;
}
if (data) {
// skip the stream to the part of the table we want to copy from
stream->rewind();
size_t bytesToSkip = realOffset + offset;
if (!skip(stream, bytesToSkip)) {
return 0;
}
if (!read(stream, data, length)) {
return 0;
}
}
return length;
}
}
return 0;
}
int SkFontStream::GetTableTags(SkStream* stream, int ttcIndex,
SkFontTableTag tags[]) {
SfntHeader header;
if (!header.init(stream, ttcIndex)) {
return 0;
}
if (tags) {
for (int i = 0; i < header.fCount; i++) {
tags[i] = SkEndian_SwapBE32(header.fDir[i].fTag);
}
}
return header.fCount;
}
int SkFontHost::GetTableTags(SkFontID fontID, SkFontTableTag tags[]) {
SkStream* stream = SkFontHost::OpenStream(fontID);
if (NULL == stream) {
return 0;
}
SkAutoUnref au(stream);
SfntHeader header;
if (!header.init(stream)) {
return 0;
}
for (int i = 0; i < header.fCount; i++) {
tags[i] = SkEndian_SwapBE32(header.fDir[i].fTag);
}
return header.fCount;
}
size_t DWriteFontTypeface::onGetTableData(SkFontTableTag tag, size_t offset,
size_t length, void* data) const
{
AutoDWriteTable table(fDWriteFontFace.get(), SkEndian_SwapBE32(tag));
if (!table.fExists) {
return 0;
}
if (offset > table.fSize) {
return 0;
}
size_t size = SkTMin(length, table.fSize - offset);
if (data) {
memcpy(data, table.fData + offset, size);
}
return size;
}
SkData* SkOTUtils::RenameFont(SkStream* fontData, const char* fontName, int fontNameLen) {
// Get the sfnt header.
SkSFNTHeader sfntHeader;
if (fontData->read(&sfntHeader, sizeof(sfntHeader)) < sizeof(sfntHeader)) {
return NULL;
}
// Find the existing 'name' table.
int tableIndex;
SkSFNTHeader::TableDirectoryEntry tableEntry;
int numTables = SkEndian_SwapBE16(sfntHeader.numTables);
for (tableIndex = 0; tableIndex < numTables; ++tableIndex) {
if (fontData->read(&tableEntry, sizeof(tableEntry)) < sizeof(tableEntry)) {
return NULL;
}
if (SkOTTableName::TAG == tableEntry.tag) {
break;
}
}
if (tableIndex == numTables) {
return NULL;
}
if (!fontData->rewind()) {
return NULL;
}
// The required 'name' record types: Family, Style, Unique, Full and PostScript.
const SkOTTableName::Record::NameID::Predefined::Value namesToCreate[] = {
SkOTTableName::Record::NameID::Predefined::FontFamilyName,
SkOTTableName::Record::NameID::Predefined::FontSubfamilyName,
SkOTTableName::Record::NameID::Predefined::UniqueFontIdentifier,
SkOTTableName::Record::NameID::Predefined::FullFontName,
SkOTTableName::Record::NameID::Predefined::PostscriptName,
};
const int namesCount = SK_ARRAY_COUNT(namesToCreate);
// Copy the data, leaving out the old name table.
// In theory, we could also remove the DSIG table if it exists.
size_t nameTableLogicalSize = sizeof(SkOTTableName) + (namesCount * sizeof(SkOTTableName::Record)) + (fontNameLen * sizeof(wchar_t));
size_t nameTablePhysicalSize = (nameTableLogicalSize + 3) & ~3; // Rounded up to a multiple of 4.
size_t oldNameTablePhysicalSize = (SkEndian_SwapBE32(tableEntry.logicalLength) + 3) & ~3; // Rounded up to a multiple of 4.
size_t oldNameTableOffset = SkEndian_SwapBE32(tableEntry.offset);
//originalDataSize is the size of the original data without the name table.
size_t originalDataSize = fontData->getLength() - oldNameTablePhysicalSize;
size_t newDataSize = originalDataSize + nameTablePhysicalSize;
SK_OT_BYTE* data = static_cast<SK_OT_BYTE*>(sk_malloc_throw(newDataSize));
SkAutoTUnref<SkData> rewrittenFontData(SkData::NewFromMalloc(data, newDataSize));
if (fontData->read(data, oldNameTableOffset) < oldNameTableOffset) {
return NULL;
}
if (fontData->skip(oldNameTablePhysicalSize) < oldNameTablePhysicalSize) {
return NULL;
}
if (fontData->read(data + oldNameTableOffset, originalDataSize - oldNameTableOffset) < originalDataSize - oldNameTableOffset) {
return NULL;
}
//Fix up the offsets of the directory entries after the old 'name' table entry.
SkSFNTHeader::TableDirectoryEntry* currentEntry = reinterpret_cast<SkSFNTHeader::TableDirectoryEntry*>(data + sizeof(SkSFNTHeader));
SkSFNTHeader::TableDirectoryEntry* endEntry = currentEntry + numTables;
SkSFNTHeader::TableDirectoryEntry* headTableEntry = NULL;
for (; currentEntry < endEntry; ++currentEntry) {
uint32_t oldOffset = SkEndian_SwapBE32(currentEntry->offset);
if (oldOffset > oldNameTableOffset) {
currentEntry->offset = SkEndian_SwapBE32(oldOffset - oldNameTablePhysicalSize);
}
if (SkOTTableHead::TAG == currentEntry->tag) {
headTableEntry = currentEntry;
}
}
// Make the table directory entry point to the new 'name' table.
SkSFNTHeader::TableDirectoryEntry* nameTableEntry = reinterpret_cast<SkSFNTHeader::TableDirectoryEntry*>(data + sizeof(SkSFNTHeader)) + tableIndex;
nameTableEntry->logicalLength = SkEndian_SwapBE32(nameTableLogicalSize);
nameTableEntry->offset = SkEndian_SwapBE32(originalDataSize);
// Write the new 'name' table after the original font data.
SkOTTableName* nameTable = reinterpret_cast<SkOTTableName*>(data + originalDataSize);
unsigned short stringOffset = sizeof(SkOTTableName) + (namesCount * sizeof(SkOTTableName::Record));
nameTable->format = SkOTTableName::format_0;
nameTable->count = SkEndian_SwapBE16(namesCount);
nameTable->stringOffset = SkEndian_SwapBE16(stringOffset);
SkOTTableName::Record* nameRecords = reinterpret_cast<SkOTTableName::Record*>(data + originalDataSize + sizeof(SkOTTableName));
for (int i = 0; i < namesCount; ++i) {
nameRecords[i].platformID.value = SkOTTableName::Record::PlatformID::Windows;
nameRecords[i].encodingID.windows.value = SkOTTableName::Record::EncodingID::Windows::UnicodeBMPUCS2;
nameRecords[i].languageID.windows.value = SkOTTableName::Record::LanguageID::Windows::English_UnitedStates;
nameRecords[i].nameID.predefined.value = namesToCreate[i];
nameRecords[i].offset = SkEndian_SwapBE16(0);
nameRecords[i].length = SkEndian_SwapBE16(fontNameLen * sizeof(wchar_t));
}
SK_OT_USHORT* nameString = reinterpret_cast<SK_OT_USHORT*>(data + originalDataSize + stringOffset);
for (int i = 0; i < fontNameLen; ++i) {
nameString[i] = SkEndian_SwapBE16(fontName[i]);
}
unsigned char* logical = data + originalDataSize + nameTableLogicalSize;
unsigned char* physical = data + originalDataSize + nameTablePhysicalSize;
for (; logical < physical; ++logical) {
*logical = 0;
}
// Update the table checksum in the directory entry.
nameTableEntry->checksum = SkEndian_SwapBE32(SkOTUtils::CalcTableChecksum(reinterpret_cast<SK_OT_ULONG*>(nameTable), nameTableLogicalSize));
// Update the checksum adjustment in the head table.
if (headTableEntry) {
size_t headTableOffset = SkEndian_SwapBE32(headTableEntry->offset);
if (headTableOffset + sizeof(SkOTTableHead) < originalDataSize) {
SkOTTableHead* headTable = reinterpret_cast<SkOTTableHead*>(data + headTableOffset);
headTable->checksumAdjustment = SkEndian_SwapBE32(0);
uint32_t unadjustedFontChecksum = SkOTUtils::CalcTableChecksum(reinterpret_cast<SK_OT_ULONG*>(data), originalDataSize + nameTablePhysicalSize);
headTable->checksumAdjustment = SkEndian_SwapBE32(SkOTTableHead::fontChecksum - unadjustedFontChecksum);
}
}
return rewrittenFontData.detach();
}
