michael@0: /*
michael@0:  * Copyright 2012 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include "SkData.h"
michael@0: #include "SkEndian.h"
michael@0: #include "SkSFNTHeader.h"
michael@0: #include "SkStream.h"
michael@0: #include "SkOTTable_head.h"
michael@0: #include "SkOTTable_name.h"
michael@0: #include "SkOTTableTypes.h"
michael@0: #include "SkOTUtils.h"
michael@0: 
michael@0: extern const uint8_t SK_OT_GlyphData_NoOutline[] = {
michael@0:     0x0,0x0, //SkOTTableGlyphData::numberOfContours
michael@0:     0x0,0x0, //SkOTTableGlyphData::xMin
michael@0:     0x0,0x0, //SkOTTableGlyphData::yMin
michael@0:     0x0,0x0, //SkOTTableGlyphData::xMax
michael@0:     0x0,0x0, //SkOTTableGlyphData::yMax
michael@0: 
michael@0:     0x0,0x0, //SkOTTableGlyphDataInstructions::length
michael@0: };
michael@0: 
michael@0: uint32_t SkOTUtils::CalcTableChecksum(SK_OT_ULONG *data, size_t length) {
michael@0:     uint32_t sum = 0;
michael@0:     SK_OT_ULONG *dataEnd = data + ((length + 3) & ~3) / sizeof(SK_OT_ULONG);
michael@0:     for (; data < dataEnd; ++data) {
michael@0:         sum += SkEndian_SwapBE32(*data);
michael@0:     }
michael@0:     return sum;
michael@0: }
michael@0: 
michael@0: SkData* SkOTUtils::RenameFont(SkStream* fontData, const char* fontName, int fontNameLen) {
michael@0: 
michael@0:     // Get the sfnt header.
michael@0:     SkSFNTHeader sfntHeader;
michael@0:     if (fontData->read(&sfntHeader, sizeof(sfntHeader)) < sizeof(sfntHeader)) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     // Find the existing 'name' table.
michael@0:     int tableIndex;
michael@0:     SkSFNTHeader::TableDirectoryEntry tableEntry;
michael@0:     int numTables = SkEndian_SwapBE16(sfntHeader.numTables);
michael@0:     for (tableIndex = 0; tableIndex < numTables; ++tableIndex) {
michael@0:         if (fontData->read(&tableEntry, sizeof(tableEntry)) < sizeof(tableEntry)) {
michael@0:             return NULL;
michael@0:         }
michael@0:         if (SkOTTableName::TAG == tableEntry.tag) {
michael@0:             break;
michael@0:         }
michael@0:     }
michael@0:     if (tableIndex == numTables) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     if (!fontData->rewind()) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     // The required 'name' record types: Family, Style, Unique, Full and PostScript.
michael@0:     const SkOTTableName::Record::NameID::Predefined::Value namesToCreate[] = {
michael@0:         SkOTTableName::Record::NameID::Predefined::FontFamilyName,
michael@0:         SkOTTableName::Record::NameID::Predefined::FontSubfamilyName,
michael@0:         SkOTTableName::Record::NameID::Predefined::UniqueFontIdentifier,
michael@0:         SkOTTableName::Record::NameID::Predefined::FullFontName,
michael@0:         SkOTTableName::Record::NameID::Predefined::PostscriptName,
michael@0:     };
michael@0:     const int namesCount = SK_ARRAY_COUNT(namesToCreate);
michael@0: 
michael@0:     // Copy the data, leaving out the old name table.
michael@0:     // In theory, we could also remove the DSIG table if it exists.
michael@0:     size_t nameTableLogicalSize = sizeof(SkOTTableName) + (namesCount * sizeof(SkOTTableName::Record)) + (fontNameLen * sizeof(wchar_t));
michael@0:     size_t nameTablePhysicalSize = (nameTableLogicalSize + 3) & ~3; // Rounded up to a multiple of 4.
michael@0: 
michael@0:     size_t oldNameTablePhysicalSize = (SkEndian_SwapBE32(tableEntry.logicalLength) + 3) & ~3; // Rounded up to a multiple of 4.
michael@0:     size_t oldNameTableOffset = SkEndian_SwapBE32(tableEntry.offset);
michael@0: 
michael@0:     //originalDataSize is the size of the original data without the name table.
michael@0:     size_t originalDataSize = fontData->getLength() - oldNameTablePhysicalSize;
michael@0:     size_t newDataSize = originalDataSize + nameTablePhysicalSize;
michael@0: 
michael@0:     SK_OT_BYTE* data = static_cast<SK_OT_BYTE*>(sk_malloc_throw(newDataSize));
michael@0:     SkAutoTUnref<SkData> rewrittenFontData(SkData::NewFromMalloc(data, newDataSize));
michael@0: 
michael@0:     if (fontData->read(data, oldNameTableOffset) < oldNameTableOffset) {
michael@0:         return NULL;
michael@0:     }
michael@0:     if (fontData->skip(oldNameTablePhysicalSize) < oldNameTablePhysicalSize) {
michael@0:         return NULL;
michael@0:     }
michael@0:     if (fontData->read(data + oldNameTableOffset, originalDataSize - oldNameTableOffset) < originalDataSize - oldNameTableOffset) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     //Fix up the offsets of the directory entries after the old 'name' table entry.
michael@0:     SkSFNTHeader::TableDirectoryEntry* currentEntry = reinterpret_cast<SkSFNTHeader::TableDirectoryEntry*>(data + sizeof(SkSFNTHeader));
michael@0:     SkSFNTHeader::TableDirectoryEntry* endEntry = currentEntry + numTables;
michael@0:     SkSFNTHeader::TableDirectoryEntry* headTableEntry = NULL;
michael@0:     for (; currentEntry < endEntry; ++currentEntry) {
michael@0:         uint32_t oldOffset = SkEndian_SwapBE32(currentEntry->offset);
michael@0:         if (oldOffset > oldNameTableOffset) {
michael@0:             currentEntry->offset = SkEndian_SwapBE32(oldOffset - oldNameTablePhysicalSize);
michael@0:         }
michael@0:         if (SkOTTableHead::TAG == currentEntry->tag) {
michael@0:             headTableEntry = currentEntry;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // Make the table directory entry point to the new 'name' table.
michael@0:     SkSFNTHeader::TableDirectoryEntry* nameTableEntry = reinterpret_cast<SkSFNTHeader::TableDirectoryEntry*>(data + sizeof(SkSFNTHeader)) + tableIndex;
michael@0:     nameTableEntry->logicalLength = SkEndian_SwapBE32(nameTableLogicalSize);
michael@0:     nameTableEntry->offset = SkEndian_SwapBE32(originalDataSize);
michael@0: 
michael@0:     // Write the new 'name' table after the original font data.
michael@0:     SkOTTableName* nameTable = reinterpret_cast<SkOTTableName*>(data + originalDataSize);
michael@0:     unsigned short stringOffset = sizeof(SkOTTableName) + (namesCount * sizeof(SkOTTableName::Record));
michael@0:     nameTable->format = SkOTTableName::format_0;
michael@0:     nameTable->count = SkEndian_SwapBE16(namesCount);
michael@0:     nameTable->stringOffset = SkEndian_SwapBE16(stringOffset);
michael@0: 
michael@0:     SkOTTableName::Record* nameRecords = reinterpret_cast<SkOTTableName::Record*>(data + originalDataSize + sizeof(SkOTTableName));
michael@0:     for (int i = 0; i < namesCount; ++i) {
michael@0:         nameRecords[i].platformID.value = SkOTTableName::Record::PlatformID::Windows;
michael@0:         nameRecords[i].encodingID.windows.value = SkOTTableName::Record::EncodingID::Windows::UnicodeBMPUCS2;
michael@0:         nameRecords[i].languageID.windows.value = SkOTTableName::Record::LanguageID::Windows::English_UnitedStates;
michael@0:         nameRecords[i].nameID.predefined.value = namesToCreate[i];
michael@0:         nameRecords[i].offset = SkEndian_SwapBE16(0);
michael@0:         nameRecords[i].length = SkEndian_SwapBE16(fontNameLen * sizeof(wchar_t));
michael@0:     }
michael@0: 
michael@0:     SK_OT_USHORT* nameString = reinterpret_cast<SK_OT_USHORT*>(data + originalDataSize + stringOffset);
michael@0:     for (int i = 0; i < fontNameLen; ++i) {
michael@0:         nameString[i] = SkEndian_SwapBE16(fontName[i]);
michael@0:     }
michael@0: 
michael@0:     unsigned char* logical = data + originalDataSize + nameTableLogicalSize;
michael@0:     unsigned char* physical = data + originalDataSize + nameTablePhysicalSize;
michael@0:     for (; logical < physical; ++logical) {
michael@0:         *logical = 0;
michael@0:     }
michael@0: 
michael@0:     // Update the table checksum in the directory entry.
michael@0:     nameTableEntry->checksum = SkEndian_SwapBE32(SkOTUtils::CalcTableChecksum(reinterpret_cast<SK_OT_ULONG*>(nameTable), nameTableLogicalSize));
michael@0: 
michael@0:     // Update the checksum adjustment in the head table.
michael@0:     if (headTableEntry) {
michael@0:         size_t headTableOffset = SkEndian_SwapBE32(headTableEntry->offset);
michael@0:         if (headTableOffset + sizeof(SkOTTableHead) < originalDataSize) {
michael@0:             SkOTTableHead* headTable = reinterpret_cast<SkOTTableHead*>(data + headTableOffset);
michael@0:             headTable->checksumAdjustment = SkEndian_SwapBE32(0);
michael@0:             uint32_t unadjustedFontChecksum = SkOTUtils::CalcTableChecksum(reinterpret_cast<SK_OT_ULONG*>(data), originalDataSize + nameTablePhysicalSize);
michael@0:             headTable->checksumAdjustment = SkEndian_SwapBE32(SkOTTableHead::fontChecksum - unadjustedFontChecksum);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     return rewrittenFontData.detach();
michael@0: }
michael@0: 
michael@0: 
michael@0: SkOTUtils::LocalizedStrings_NameTable*
michael@0: SkOTUtils::LocalizedStrings_NameTable::CreateForFamilyNames(const SkTypeface& typeface) {
michael@0:     static const SkFontTableTag nameTag = SkSetFourByteTag('n','a','m','e');
michael@0:     size_t nameTableSize = typeface.getTableSize(nameTag);
michael@0:     if (0 == nameTableSize) {
michael@0:         return NULL;
michael@0:     }
michael@0:     SkAutoTDeleteArray<uint8_t> nameTableData(new uint8_t[nameTableSize]);
michael@0:     size_t copied = typeface.getTableData(nameTag, 0, nameTableSize, nameTableData.get());
michael@0:     if (copied != nameTableSize) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     return new SkOTUtils::LocalizedStrings_NameTable((SkOTTableName*)nameTableData.detach(),
michael@0:         SkOTUtils::LocalizedStrings_NameTable::familyNameTypes,
michael@0:         SK_ARRAY_COUNT(SkOTUtils::LocalizedStrings_NameTable::familyNameTypes));
michael@0: }
michael@0: 
michael@0: bool SkOTUtils::LocalizedStrings_NameTable::next(SkTypeface::LocalizedString* localizedString) {
michael@0:     do {
michael@0:         SkOTTableName::Iterator::Record record;
michael@0:         if (fFamilyNameIter.next(record)) {
michael@0:             localizedString->fString = record.name;
michael@0:             localizedString->fLanguage = record.language;
michael@0:             return true;
michael@0:         }
michael@0:         if (fTypesCount == fTypesIndex + 1) {
michael@0:             return false;
michael@0:         }
michael@0:         ++fTypesIndex;
michael@0:         fFamilyNameIter.reset(fTypes[fTypesIndex]);
michael@0:     } while (true);
michael@0: }
michael@0: 
michael@0: SkOTTableName::Record::NameID::Predefined::Value
michael@0: SkOTUtils::LocalizedStrings_NameTable::familyNameTypes[3] = {
michael@0:     SkOTTableName::Record::NameID::Predefined::FontFamilyName,
michael@0:     SkOTTableName::Record::NameID::Predefined::PreferredFamily,
michael@0:     SkOTTableName::Record::NameID::Predefined::WWSFamilyName,
michael@0: };