Add dynamic web font support to Chrome's port of Webkit. ...

third_party/WebKit/WebCore/platform/graphics/win/OpenTypeUtilities.cpp

Index: third_party/WebKit/WebCore/platform/graphics/win/OpenTypeUtilities.cpp
===================================================================
--- third_party/WebKit/WebCore/platform/graphics/win/OpenTypeUtilities.cpp	(revision 7512)
+++ third_party/WebKit/WebCore/platform/graphics/win/OpenTypeUtilities.cpp	(working copy)
@@ -1,387 +0,0 @@
-/*
- * Copyright (C) 2008 Apple Inc.  All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
- * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
- */
-
-#include "config.h"
-#include "OpenTypeUtilities.h"
-
-#include "SharedBuffer.h"
-
-namespace WebCore {
-
-struct BigEndianUShort { 
-    operator unsigned short() const { return (v & 0x00ff) << 8 | v >> 8; }
-    BigEndianUShort(unsigned short u) : v((u & 0x00ff) << 8 | u >> 8) { }
-    unsigned short v;
-};
-
-struct BigEndianULong { 
-    operator unsigned() const { return (v & 0xff) << 24 | (v & 0xff00) << 8 | (v & 0xff0000) >> 8 | v >> 24; }
-    BigEndianULong(unsigned u) : v((u & 0xff) << 24 | (u & 0xff00) << 8 | (u & 0xff0000) >> 8 | u >> 24) { }
-    unsigned v;
-};
-
-#pragma pack(1)
-
-struct EOTPrefix {
-    unsigned eotSize;
-    unsigned fontDataSize;
-    unsigned version;
-    unsigned flags;
-    UInt8 fontPANOSE[10];
-    UInt8 charset;
-    UInt8 italic;
-    unsigned weight;
-    unsigned short fsType;
-    unsigned short magicNumber;
-    unsigned unicodeRange[4];
-    unsigned codePageRange[2];
-    unsigned checkSumAdjustment;
-    unsigned reserved[4];
-    unsigned short padding1;
-};
-
-struct TableDirectoryEntry {
-    BigEndianULong tag;
-    BigEndianULong checkSum;
-    BigEndianULong offset;
-    BigEndianULong length;
-};
-
-struct sfntHeader {
-    Fixed version;
-    BigEndianUShort numTables;
-    BigEndianUShort searchRange;
-    BigEndianUShort entrySelector;
-    BigEndianUShort rangeShift;
-    TableDirectoryEntry tables[1];
-};
-
-struct OS2Table {
-    BigEndianUShort version;
-    BigEndianUShort avgCharWidth;
-    BigEndianUShort weightClass;
-    BigEndianUShort widthClass;
-    BigEndianUShort fsType;
-    BigEndianUShort subscriptXSize;
-    BigEndianUShort subscriptYSize;
-    BigEndianUShort subscriptXOffset;
-    BigEndianUShort subscriptYOffset;
-    BigEndianUShort superscriptXSize;
-    BigEndianUShort superscriptYSize;
-    BigEndianUShort superscriptXOffset;
-    BigEndianUShort superscriptYOffset;
-    BigEndianUShort strikeoutSize;
-    BigEndianUShort strikeoutPosition;
-    BigEndianUShort familyClass;
-    UInt8 panose[10];
-    BigEndianULong unicodeRange[4];
-    UInt8 vendID[4];
-    BigEndianUShort fsSelection;
-    BigEndianUShort firstCharIndex;
-    BigEndianUShort lastCharIndex;
-    BigEndianUShort typoAscender;
-    BigEndianUShort typoDescender;
-    BigEndianUShort typoLineGap;
-    BigEndianUShort winAscent;
-    BigEndianUShort winDescent;
-    BigEndianULong codePageRange[2];
-    BigEndianUShort xHeight;
-    BigEndianUShort capHeight;
-    BigEndianUShort defaultChar;
-    BigEndianUShort breakChar;
-    BigEndianUShort maxContext;
-};
-
-struct headTable {
-    Fixed version;
-    Fixed fontRevision;
-    BigEndianULong checkSumAdjustment;
-    BigEndianULong magicNumber;
-    BigEndianUShort flags;
-    BigEndianUShort unitsPerEm;
-    long long created;
-    long long modified;
-    BigEndianUShort xMin;
-    BigEndianUShort xMax;
-    BigEndianUShort yMin;
-    BigEndianUShort yMax;
-    BigEndianUShort macStyle;
-    BigEndianUShort lowestRectPPEM;
-    BigEndianUShort fontDirectionHint;
-    BigEndianUShort indexToLocFormat;
-    BigEndianUShort glyphDataFormat;
-};
-
-struct nameRecord {
-    BigEndianUShort platformID;
-    BigEndianUShort encodingID;
-    BigEndianUShort languageID;
-    BigEndianUShort nameID;
-    BigEndianUShort length;
-    BigEndianUShort offset;
-};
-
-struct nameTable {
-    BigEndianUShort format;
-    BigEndianUShort count;
-    BigEndianUShort stringOffset;
-    nameRecord nameRecords[1];
-};
-
-#pragma pack()
-
-static void appendBigEndianStringToEOTHeader(Vector<UInt8, 512>& eotHeader, const BigEndianUShort* string, unsigned short length)
-{
-    size_t size = eotHeader.size();
-    eotHeader.resize(size + length + 2 * sizeof(unsigned short));
-    UChar* dst = reinterpret_cast<UChar*>(eotHeader.data() + size);
-    unsigned i = 0;
-    dst[i++] = length;
-    unsigned numCharacters = length / 2;
-    for (unsigned j = 0; j < numCharacters; j++)
-        dst[i++] = string[j];
-    dst[i] = 0;
-}
-
-bool getEOTHeader(SharedBuffer* fontData, Vector<UInt8, 512>& eotHeader, size_t& overlayDst, size_t& overlaySrc, size_t& overlayLength)
-{
-    overlayDst = 0;
-    overlaySrc = 0;
-    overlayLength = 0;
-
-    size_t dataLength = fontData->size();
-    const char* data = fontData->data();
-
-    eotHeader.resize(sizeof(EOTPrefix));
-    EOTPrefix* prefix = reinterpret_cast<EOTPrefix*>(eotHeader.data());
-
-    prefix->fontDataSize = dataLength;
-    prefix->version = 0x00020001;
-    prefix->flags = 0;
-
-    if (dataLength < offsetof(sfntHeader, tables))
-        return false;
-
-    const sfntHeader* sfnt = reinterpret_cast<const sfntHeader*>(data);
-
-    if (dataLength < offsetof(sfntHeader, tables) + sfnt->numTables * sizeof(TableDirectoryEntry))
-        return false;
-
-    bool haveOS2 = false;
-    bool haveHead = false;
-    bool haveName = false;
-
-    const BigEndianUShort* familyName = 0;
-    unsigned short familyNameLength = 0;
-    const BigEndianUShort* subfamilyName = 0;
-    unsigned short subfamilyNameLength = 0;
-    const BigEndianUShort* fullName = 0;
-    unsigned short fullNameLength = 0;
-    const BigEndianUShort* versionString = 0;
-    unsigned short versionStringLength = 0;
-
-    for (unsigned i = 0; i < sfnt->numTables; i++) {
-        unsigned tableOffset = sfnt->tables[i].offset;
-        unsigned tableLength = sfnt->tables[i].length;
-
-        if (dataLength < tableOffset || dataLength < tableLength || dataLength < tableOffset + tableLength)
-            return false;
-
-        unsigned tableTag = sfnt->tables[i].tag;
-        switch (tableTag) {
-            case 'OS/2':
-                {
-                    if (dataLength < tableOffset + sizeof(OS2Table))
-                        return false;
-
-                    haveOS2 = true;
-                    const OS2Table* OS2 = reinterpret_cast<const OS2Table*>(data + tableOffset);
-                    for (unsigned j = 0; j < 10; j++)
-                        prefix->fontPANOSE[j] = OS2->panose[j];
-                    prefix->italic = OS2->fsSelection & 0x01;
-                    prefix->weight = OS2->weightClass;
-                    // FIXME: Should use OS2->fsType, but some TrueType fonts set it to an over-restrictive value.
-                    // Since ATS does not enforce this on Mac OS X, we do not enforce it either.
-                    prefix->fsType = 0;            
-                    for (unsigned j = 0; j < 4; j++)
-                        prefix->unicodeRange[j] = OS2->unicodeRange[j];
-                    for (unsigned j = 0; j < 2; j++)
-                        prefix->codePageRange[j] = OS2->codePageRange[j];
-                    break;
-                }
-            case 'head':
-                {
-                    if (dataLength < tableOffset + sizeof(headTable))
-                        return false;
-
-                    haveHead = true;
-                    const headTable* head = reinterpret_cast<const headTable*>(data + tableOffset);
-                    prefix->checkSumAdjustment = head->checkSumAdjustment;
-                    break;
-                }
-            case 'name':
-                {
-                    if (dataLength < tableOffset + offsetof(nameTable, nameRecords))
-                        return false;
-
-                    haveName = true;
-                    const nameTable* name = reinterpret_cast<const nameTable*>(data + tableOffset);
-                    for (int j = 0; j < name->count; j++) {
-                        if (dataLength < tableOffset + offsetof(nameTable, nameRecords) + (j + 1) * sizeof(nameRecord))
-                            return false;
-                        if (name->nameRecords[j].platformID == 3 && name->nameRecords[j].encodingID == 1 && name->nameRecords[j].languageID == 0x0409) {
-                            if (dataLength < tableOffset + name->stringOffset + name->nameRecords[j].offset + name->nameRecords[j].length)
-                                return false;
-
-                            unsigned short nameLength = name->nameRecords[j].length;
-                            const BigEndianUShort* nameString = reinterpret_cast<const BigEndianUShort*>(data + tableOffset + name->stringOffset + name->nameRecords[j].offset);
-                            
-                            switch (name->nameRecords[j].nameID) {
-                                case 1:
-                                    familyNameLength = nameLength;
-                                    familyName = nameString;
-                                    break;
-                                case 2:
-                                    subfamilyNameLength = nameLength;
-                                    subfamilyName = nameString;
-                                    break;
-                                case 4:
-                                    fullNameLength = nameLength;
-                                    fullName = nameString;
-                                    break;
-                                case 5:
-                                    versionStringLength = nameLength;
-                                    versionString = nameString;
-                                    break;
-                                default:
-                                    break;
-                            }
-                        }
-                    }
-                    break;
-                }
-            default:
-                break;
-        }
-        if (haveOS2 && haveHead && haveName)
-            break;
-    }
-
-    prefix->charset = DEFAULT_CHARSET;
-    prefix->magicNumber = 0x504c;
-    prefix->reserved[0] = 0;
-    prefix->reserved[1] = 0;
-    prefix->reserved[2] = 0;
-    prefix->reserved[3] = 0;
-    prefix->padding1 = 0;
-
-    appendBigEndianStringToEOTHeader(eotHeader, familyName, familyNameLength);
-    appendBigEndianStringToEOTHeader(eotHeader, subfamilyName, subfamilyNameLength);
-    appendBigEndianStringToEOTHeader(eotHeader, versionString, versionStringLength);
-
-    // If possible, ensure that the family name is a prefix of the full name.
-    if (fullNameLength >= familyNameLength && memcmp(familyName, fullName, familyNameLength)) {
-        overlaySrc = reinterpret_cast<const char*>(fullName) - data;
-        overlayDst = reinterpret_cast<const char*>(familyName) - data;
-        overlayLength = familyNameLength;
-    }
-
-    appendBigEndianStringToEOTHeader(eotHeader, fullName, fullNameLength);
-
-    unsigned short padding = 0;
-    eotHeader.append(reinterpret_cast<UInt8*>(&padding), sizeof(padding));
-
-    prefix->eotSize = eotHeader.size() + fontData->size();
-
-    return true;
-}
-
-HANDLE renameAndActivateFont(SharedBuffer* fontData, const String& fontName)
-{
-    size_t originalDataSize = fontData->size();
-    const sfntHeader* sfnt = reinterpret_cast<const sfntHeader*>(fontData->data());
-
-    unsigned t;
-    for (t = 0; t < sfnt->numTables; ++t) {
-        if (sfnt->tables[t].tag == 'name')
-            break;
-    }
-    if (t == sfnt->numTables)
-        return 0;
-
-    const int nameRecordCount = 5;
-
-    // Rounded up to a multiple of 4 to simplify the checksum calculation.
-    size_t nameTableSize = ((offsetof(nameTable, nameRecords) + nameRecordCount * sizeof(nameRecord) + fontName.length() * sizeof(UChar)) & ~3) + 4;
-
-    Vector<char> rewrittenFontData(fontData->size() + nameTableSize);
-    char* data = rewrittenFontData.data();
-    memcpy(data, fontData->data(), originalDataSize);
-
-    // Make the table directory entry point to the new 'name' table.
-    sfntHeader* rewrittenSfnt = reinterpret_cast<sfntHeader*>(data);
-    rewrittenSfnt->tables[t].length = nameTableSize;
-    rewrittenSfnt->tables[t].offset = originalDataSize;
-
-    // Write the new 'name' table after the original font data.
-    nameTable* name = reinterpret_cast<nameTable*>(data + originalDataSize);
-    name->format = 0;
-    name->count = nameRecordCount;
-    name->stringOffset = offsetof(nameTable, nameRecords) + nameRecordCount * sizeof(nameRecord);
-    for (unsigned i = 0; i < nameRecordCount; ++i) {
-        name->nameRecords[i].platformID = 3;
-        name->nameRecords[i].encodingID = 1;
-        name->nameRecords[i].languageID = 0x0409;
-        name->nameRecords[i].offset = 0;
-        name->nameRecords[i].length = fontName.length() * sizeof(UChar);
-    }
-
-    // The required 'name' record types: Family, Style, Unique, Full and PostScript.
-    name->nameRecords[0].nameID = 1;
-    name->nameRecords[1].nameID = 2;
-    name->nameRecords[2].nameID = 3;
-    name->nameRecords[3].nameID = 4;
-    name->nameRecords[4].nameID = 6;
-
-    for (unsigned i = 0; i < fontName.length(); ++i)
-        reinterpret_cast<BigEndianUShort*>(data + originalDataSize + name->stringOffset)[i] = fontName[i];
-
-    // Update the table checksum in the directory entry.
-    rewrittenSfnt->tables[t].checkSum = 0;
-    for (unsigned i = 0; i * sizeof(BigEndianULong) < nameTableSize; ++i)
-        rewrittenSfnt->tables[t].checkSum = rewrittenSfnt->tables[t].checkSum + reinterpret_cast<BigEndianULong*>(name)[i];
-
-    DWORD numFonts = 0;
-    HANDLE fontHandle = AddFontMemResourceEx(data, originalDataSize + nameTableSize, 0, &numFonts);
-
-    if (fontHandle && numFonts != 1) {
-        RemoveFontMemResourceEx(fontHandle);
-        return 0;
-    }
-
-    return fontHandle;
-}
-
-}