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gecko-dev/gfx/thebes/gfxFontUtils.cpp

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/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/ArrayUtils.h"
#include "mozilla/BinarySearch.h"
#include "gfxFontUtils.h"
#include "gfxFontEntry.h"
#include "gfxFontVariations.h"
#include "gfxUtils.h"
#include "nsServiceManagerUtils.h"
#include "mozilla/Preferences.h"
#include "mozilla/BinarySearch.h"
#include "mozilla/Sprintf.h"
#include "mozilla/Unused.h"
#include "nsCOMPtr.h"
#include "nsIUUIDGenerator.h"
#include "mozilla/Encoding.h"
#include "mozilla/ServoStyleSet.h"
#include "mozilla/dom/WorkerCommon.h"
#include "plbase64.h"
#include "mozilla/Logging.h"
#ifdef XP_DARWIN
# include <CoreFoundation/CoreFoundation.h>
#endif
#define LOG(log, args) MOZ_LOG(gfxPlatform::GetLog(log), LogLevel::Debug, args)
#define UNICODE_BMP_LIMIT 0x10000
using namespace mozilla;
#pragma pack(1)
typedef struct {
AutoSwap_PRUint16 format;
AutoSwap_PRUint16 reserved;
AutoSwap_PRUint32 length;
AutoSwap_PRUint32 language;
AutoSwap_PRUint32 startCharCode;
AutoSwap_PRUint32 numChars;
} Format10CmapHeader;
typedef struct {
AutoSwap_PRUint16 format;
AutoSwap_PRUint16 reserved;
AutoSwap_PRUint32 length;
AutoSwap_PRUint32 language;
AutoSwap_PRUint32 numGroups;
} Format12CmapHeader;
typedef struct {
AutoSwap_PRUint32 startCharCode;
AutoSwap_PRUint32 endCharCode;
AutoSwap_PRUint32 startGlyphId;
} Format12Group;
#pragma pack()
void gfxSparseBitSet::Dump(const char* aPrefix, eGfxLog aWhichLog) const {
uint32_t numBlocks = mBlockIndex.Length();
for (uint32_t b = 0; b < numBlocks; b++) {
if (mBlockIndex[b] == NO_BLOCK) {
continue;
}
const Block* block = &mBlocks[mBlockIndex[b]];
const int BUFSIZE = 256;
char outStr[BUFSIZE];
int index = 0;
index += snprintf(&outStr[index], BUFSIZE - index, "%s u+%6.6x [", aPrefix,
(b * BLOCK_SIZE_BITS));
for (int i = 0; i < 32; i += 4) {
for (int j = i; j < i + 4; j++) {
uint8_t bits = block->mBits[j];
uint8_t flip1 = ((bits & 0xaa) >> 1) | ((bits & 0x55) << 1);
uint8_t flip2 = ((flip1 & 0xcc) >> 2) | ((flip1 & 0x33) << 2);
uint8_t flipped = ((flip2 & 0xf0) >> 4) | ((flip2 & 0x0f) << 4);
index += snprintf(&outStr[index], BUFSIZE - index, "%2.2x", flipped);
}
if (i + 4 != 32) index += snprintf(&outStr[index], BUFSIZE - index, " ");
}
Unused << snprintf(&outStr[index], BUFSIZE - index, "]");
LOG(aWhichLog, ("%s", outStr));
}
}
nsresult gfxFontUtils::ReadCMAPTableFormat10(const uint8_t* aBuf,
uint32_t aLength,
gfxSparseBitSet& aCharacterMap) {
// Ensure table is large enough that we can safely read the header
NS_ENSURE_TRUE(aLength >= sizeof(Format10CmapHeader),
NS_ERROR_GFX_CMAP_MALFORMED);
// Sanity-check header fields
const Format10CmapHeader* cmap10 =
reinterpret_cast<const Format10CmapHeader*>(aBuf);
NS_ENSURE_TRUE(uint16_t(cmap10->format) == 10, NS_ERROR_GFX_CMAP_MALFORMED);
NS_ENSURE_TRUE(uint16_t(cmap10->reserved) == 0, NS_ERROR_GFX_CMAP_MALFORMED);
uint32_t tablelen = cmap10->length;
NS_ENSURE_TRUE(tablelen >= sizeof(Format10CmapHeader) && tablelen <= aLength,
NS_ERROR_GFX_CMAP_MALFORMED);
NS_ENSURE_TRUE(cmap10->language == 0, NS_ERROR_GFX_CMAP_MALFORMED);
uint32_t numChars = cmap10->numChars;
NS_ENSURE_TRUE(
tablelen == sizeof(Format10CmapHeader) + numChars * sizeof(uint16_t),
NS_ERROR_GFX_CMAP_MALFORMED);
uint32_t charCode = cmap10->startCharCode;
NS_ENSURE_TRUE(charCode <= CMAP_MAX_CODEPOINT &&
charCode + numChars <= CMAP_MAX_CODEPOINT,
NS_ERROR_GFX_CMAP_MALFORMED);
// glyphs[] array immediately follows the subtable header
const AutoSwap_PRUint16* glyphs =
reinterpret_cast<const AutoSwap_PRUint16*>(cmap10 + 1);
for (uint32_t i = 0; i < numChars; ++i) {
if (uint16_t(*glyphs) != 0) {
aCharacterMap.set(charCode);
}
++charCode;
++glyphs;
}
aCharacterMap.Compact();
return NS_OK;
}
nsresult gfxFontUtils::ReadCMAPTableFormat12or13(
const uint8_t* aBuf, uint32_t aLength, gfxSparseBitSet& aCharacterMap) {
// Format 13 has the same structure as format 12, the only difference is
// the interpretation of the glyphID field. So we can share the code here
// that reads the table and just records character coverage.
// Ensure table is large enough that we can safely read the header
NS_ENSURE_TRUE(aLength >= sizeof(Format12CmapHeader),
NS_ERROR_GFX_CMAP_MALFORMED);
// Sanity-check header fields
const Format12CmapHeader* cmap12 =
reinterpret_cast<const Format12CmapHeader*>(aBuf);
NS_ENSURE_TRUE(
uint16_t(cmap12->format) == 12 || uint16_t(cmap12->format) == 13,
NS_ERROR_GFX_CMAP_MALFORMED);
NS_ENSURE_TRUE(uint16_t(cmap12->reserved) == 0, NS_ERROR_GFX_CMAP_MALFORMED);
uint32_t tablelen = cmap12->length;
NS_ENSURE_TRUE(tablelen >= sizeof(Format12CmapHeader) && tablelen <= aLength,
NS_ERROR_GFX_CMAP_MALFORMED);
NS_ENSURE_TRUE(cmap12->language == 0, NS_ERROR_GFX_CMAP_MALFORMED);
// Check that the table is large enough for the group array
const uint32_t numGroups = cmap12->numGroups;
NS_ENSURE_TRUE(
(tablelen - sizeof(Format12CmapHeader)) / sizeof(Format12Group) >=
numGroups,
NS_ERROR_GFX_CMAP_MALFORMED);
// The array of groups immediately follows the subtable header.
const Format12Group* group =
reinterpret_cast<const Format12Group*>(aBuf + sizeof(Format12CmapHeader));
// Check that groups are in correct order and do not overlap,
// and record character coverage in aCharacterMap.
uint32_t prevEndCharCode = 0;
for (uint32_t i = 0; i < numGroups; i++, group++) {
uint32_t startCharCode = group->startCharCode;
const uint32_t endCharCode = group->endCharCode;
NS_ENSURE_TRUE((prevEndCharCode < startCharCode || i == 0) &&
startCharCode <= endCharCode &&
endCharCode <= CMAP_MAX_CODEPOINT,
NS_ERROR_GFX_CMAP_MALFORMED);
// don't include a character that maps to glyph ID 0 (.notdef)
if (group->startGlyphId == 0) {
startCharCode++;
}
if (startCharCode <= endCharCode) {
aCharacterMap.SetRange(startCharCode, endCharCode);
}
prevEndCharCode = endCharCode;
}
aCharacterMap.Compact();
return NS_OK;
}
nsresult gfxFontUtils::ReadCMAPTableFormat4(const uint8_t* aBuf,
uint32_t aLength,
gfxSparseBitSet& aCharacterMap,
bool aIsSymbolFont) {
enum {
OffsetFormat = 0,
OffsetLength = 2,
OffsetLanguage = 4,
OffsetSegCountX2 = 6
};
NS_ENSURE_TRUE(ReadShortAt(aBuf, OffsetFormat) == 4,
NS_ERROR_GFX_CMAP_MALFORMED);
uint16_t tablelen = ReadShortAt(aBuf, OffsetLength);
NS_ENSURE_TRUE(tablelen <= aLength, NS_ERROR_GFX_CMAP_MALFORMED);
NS_ENSURE_TRUE(tablelen > 16, NS_ERROR_GFX_CMAP_MALFORMED);
// This field should normally (except for Mac platform subtables) be zero
// according to the OT spec, but some buggy fonts have lang = 1 (which would
// be English for MacOS). E.g. Arial Narrow Bold, v. 1.1 (Tiger), Arial
// Unicode MS (see bug 530614). So accept either zero or one here; the error
// should be harmless.
NS_ENSURE_TRUE((ReadShortAt(aBuf, OffsetLanguage) & 0xfffe) == 0,
NS_ERROR_GFX_CMAP_MALFORMED);
uint16_t segCountX2 = ReadShortAt(aBuf, OffsetSegCountX2);
NS_ENSURE_TRUE(tablelen >= 16 + (segCountX2 * 4),
NS_ERROR_GFX_CMAP_MALFORMED);
const uint16_t segCount = segCountX2 / 2;
const uint16_t* endCounts = reinterpret_cast<const uint16_t*>(aBuf + 14);
const uint16_t* startCounts =
endCounts + 1 /* skip one uint16_t for reservedPad */ + segCount;
const uint16_t* idDeltas = startCounts + segCount;
const uint16_t* idRangeOffsets = idDeltas + segCount;
uint16_t prevEndCount = 0;
for (uint16_t i = 0; i < segCount; i++) {
const uint16_t endCount = ReadShortAt16(endCounts, i);
const uint16_t startCount = ReadShortAt16(startCounts, i);
const uint16_t idRangeOffset = ReadShortAt16(idRangeOffsets, i);
// sanity-check range
// This permits ranges to overlap by 1 character, which is strictly
// incorrect but occurs in Baskerville on OS X 10.7 (see bug 689087),
// and appears to be harmless in practice
NS_ENSURE_TRUE(startCount >= prevEndCount && startCount <= endCount,
NS_ERROR_GFX_CMAP_MALFORMED);
prevEndCount = endCount;
if (idRangeOffset == 0) {
// figure out if there's a code in the range that would map to
// glyph ID 0 (.notdef); if so, we need to skip setting that
// character code in the map
const uint16_t skipCode = 65536 - ReadShortAt16(idDeltas, i);
if (startCount < skipCode) {
aCharacterMap.SetRange(startCount,
std::min<uint16_t>(skipCode - 1, endCount));
}
if (skipCode < endCount) {
aCharacterMap.SetRange(std::max<uint16_t>(startCount, skipCode + 1),
endCount);
}
} else {
// Unused: self-documenting.
// const uint16_t idDelta = ReadShortAt16(idDeltas, i);
for (uint32_t c = startCount; c <= endCount; ++c) {
if (c == 0xFFFF) break;
const uint16_t* gdata =
(idRangeOffset / 2 + (c - startCount) + &idRangeOffsets[i]);
NS_ENSURE_TRUE(
(uint8_t*)gdata > aBuf && (uint8_t*)gdata < aBuf + aLength,
NS_ERROR_GFX_CMAP_MALFORMED);
// make sure we have a glyph
if (*gdata != 0) {
// The glyph index at this point is:
uint16_t glyph = ReadShortAt16(idDeltas, i) + *gdata;
if (glyph) {
aCharacterMap.set(c);
}
}
}
}
}
if (aIsSymbolFont) {
// For fonts with "MS Symbol" encoding, we duplicate character mappings in
// the U+F0xx range down to U+00xx codepoints, so as to support fonts such
// as Wingdings.
// Note that if the font actually has cmap coverage for the U+00xx range
// (either duplicating the PUA codepoints or mapping to separate glyphs),
// this will not affect it.
for (uint32_t c = 0x0020; c <= 0x00ff; ++c) {
if (aCharacterMap.test(0xf000 + c)) {
aCharacterMap.set(c);
}
}
}
aCharacterMap.Compact();
return NS_OK;
}
nsresult gfxFontUtils::ReadCMAPTableFormat14(const uint8_t* aBuf,
uint32_t aLength,
const uint8_t*& aTable) {
enum {
OffsetFormat = 0,
OffsetTableLength = 2,
OffsetNumVarSelectorRecords = 6,
OffsetVarSelectorRecords = 10,
SizeOfVarSelectorRecord = 11,
VSRecOffsetVarSelector = 0,
VSRecOffsetDefUVSOffset = 3,
VSRecOffsetNonDefUVSOffset = 7,
SizeOfDefUVSTable = 4,
DefUVSOffsetStartUnicodeValue = 0,
DefUVSOffsetAdditionalCount = 3,
SizeOfNonDefUVSTable = 5,
NonDefUVSOffsetUnicodeValue = 0,
NonDefUVSOffsetGlyphID = 3
};
NS_ENSURE_TRUE(aLength >= OffsetVarSelectorRecords,
NS_ERROR_GFX_CMAP_MALFORMED);
NS_ENSURE_TRUE(ReadShortAt(aBuf, OffsetFormat) == 14,
NS_ERROR_GFX_CMAP_MALFORMED);
uint32_t tablelen = ReadLongAt(aBuf, OffsetTableLength);
NS_ENSURE_TRUE(tablelen <= aLength, NS_ERROR_GFX_CMAP_MALFORMED);
NS_ENSURE_TRUE(tablelen >= OffsetVarSelectorRecords,
NS_ERROR_GFX_CMAP_MALFORMED);
const uint32_t numVarSelectorRecords =
ReadLongAt(aBuf, OffsetNumVarSelectorRecords);
NS_ENSURE_TRUE(
(tablelen - OffsetVarSelectorRecords) / SizeOfVarSelectorRecord >=
numVarSelectorRecords,
NS_ERROR_GFX_CMAP_MALFORMED);
const uint8_t* records = aBuf + OffsetVarSelectorRecords;
for (uint32_t i = 0; i < numVarSelectorRecords;
i++, records += SizeOfVarSelectorRecord) {
const uint32_t varSelector = ReadUint24At(records, VSRecOffsetVarSelector);
const uint32_t defUVSOffset = ReadLongAt(records, VSRecOffsetDefUVSOffset);
const uint32_t nonDefUVSOffset =
ReadLongAt(records, VSRecOffsetNonDefUVSOffset);
NS_ENSURE_TRUE(varSelector <= CMAP_MAX_CODEPOINT &&
defUVSOffset <= tablelen - 4 &&
nonDefUVSOffset <= tablelen - 4,
NS_ERROR_GFX_CMAP_MALFORMED);
if (defUVSOffset) {
const uint32_t numUnicodeValueRanges = ReadLongAt(aBuf, defUVSOffset);
NS_ENSURE_TRUE((tablelen - defUVSOffset) / SizeOfDefUVSTable >=
numUnicodeValueRanges,
NS_ERROR_GFX_CMAP_MALFORMED);
const uint8_t* tables = aBuf + defUVSOffset + 4;
uint32_t prevEndUnicode = 0;
for (uint32_t j = 0; j < numUnicodeValueRanges;
j++, tables += SizeOfDefUVSTable) {
const uint32_t startUnicode =
ReadUint24At(tables, DefUVSOffsetStartUnicodeValue);
const uint32_t endUnicode =
startUnicode + tables[DefUVSOffsetAdditionalCount];
NS_ENSURE_TRUE((prevEndUnicode < startUnicode || j == 0) &&
endUnicode <= CMAP_MAX_CODEPOINT,
NS_ERROR_GFX_CMAP_MALFORMED);
prevEndUnicode = endUnicode;
}
}
if (nonDefUVSOffset) {
const uint32_t numUVSMappings = ReadLongAt(aBuf, nonDefUVSOffset);
NS_ENSURE_TRUE(
(tablelen - nonDefUVSOffset) / SizeOfNonDefUVSTable >= numUVSMappings,
NS_ERROR_GFX_CMAP_MALFORMED);
const uint8_t* tables = aBuf + nonDefUVSOffset + 4;
uint32_t prevUnicode = 0;
for (uint32_t j = 0; j < numUVSMappings;
j++, tables += SizeOfNonDefUVSTable) {
const uint32_t unicodeValue =
ReadUint24At(tables, NonDefUVSOffsetUnicodeValue);
NS_ENSURE_TRUE((prevUnicode < unicodeValue || j == 0) &&
unicodeValue <= CMAP_MAX_CODEPOINT,
NS_ERROR_GFX_CMAP_MALFORMED);
prevUnicode = unicodeValue;
}
}
}
uint8_t* table = new uint8_t[tablelen];
memcpy(table, aBuf, tablelen);
aTable = static_cast<const uint8_t*>(table);
return NS_OK;
}
// For fonts with two format-4 tables, the first one (Unicode platform) is
// preferred on the Mac; on other platforms we allow the Microsoft-platform
// subtable to replace it.
#if defined(XP_MACOSX)
# define acceptableFormat4(p, e, k) \
(((p) == PLATFORM_ID_MICROSOFT && (e) == EncodingIDMicrosoft && !(k)) || \
((p) == PLATFORM_ID_UNICODE))
# define acceptableUCS4Encoding(p, e, k) \
(((p) == PLATFORM_ID_MICROSOFT && \
(e) == EncodingIDUCS4ForMicrosoftPlatform) && \
(k) != 12 || \
((p) == PLATFORM_ID_UNICODE && ((e) != EncodingIDUVSForUnicodePlatform)))
#else
# define acceptableFormat4(p, e, k) \
(((p) == PLATFORM_ID_MICROSOFT && (e) == EncodingIDMicrosoft) || \
((p) == PLATFORM_ID_UNICODE))
# define acceptableUCS4Encoding(p, e, k) \
((p) == PLATFORM_ID_MICROSOFT && (e) == EncodingIDUCS4ForMicrosoftPlatform)
#endif
#define acceptablePlatform(p) \
((p) == PLATFORM_ID_UNICODE || (p) == PLATFORM_ID_MICROSOFT)
#define isSymbol(p, e) ((p) == PLATFORM_ID_MICROSOFT && (e) == EncodingIDSymbol)
#define isUVSEncoding(p, e) \
((p) == PLATFORM_ID_UNICODE && (e) == EncodingIDUVSForUnicodePlatform)
uint32_t gfxFontUtils::FindPreferredSubtable(const uint8_t* aBuf,
uint32_t aBufLength,
uint32_t* aTableOffset,
uint32_t* aUVSTableOffset,
bool* aIsSymbolFont) {
enum {
OffsetVersion = 0,
OffsetNumTables = 2,
SizeOfHeader = 4,
TableOffsetPlatformID = 0,
TableOffsetEncodingID = 2,
TableOffsetOffset = 4,
SizeOfTable = 8,
SubtableOffsetFormat = 0
};
enum {
EncodingIDSymbol = 0,
EncodingIDMicrosoft = 1,
EncodingIDDefaultForUnicodePlatform = 0,
EncodingIDUCS4ForUnicodePlatform = 3,
EncodingIDUVSForUnicodePlatform = 5,
EncodingIDUCS4ForMicrosoftPlatform = 10
};
if (aUVSTableOffset) {
*aUVSTableOffset = 0;
}
if (aIsSymbolFont) {
*aIsSymbolFont = false;
}
if (!aBuf || aBufLength < SizeOfHeader) {
// cmap table is missing, or too small to contain header fields!
return 0;
}
// uint16_t version = ReadShortAt(aBuf, OffsetVersion); // Unused:
// self-documenting.
uint16_t numTables = ReadShortAt(aBuf, OffsetNumTables);
if (aBufLength < uint32_t(SizeOfHeader + numTables * SizeOfTable)) {
return 0;
}
// save the format we want here
uint32_t keepFormat = 0;
const uint8_t* table = aBuf + SizeOfHeader;
for (uint16_t i = 0; i < numTables; ++i, table += SizeOfTable) {
const uint16_t platformID = ReadShortAt(table, TableOffsetPlatformID);
if (!acceptablePlatform(platformID)) continue;
const uint16_t encodingID = ReadShortAt(table, TableOffsetEncodingID);
const uint32_t offset = ReadLongAt(table, TableOffsetOffset);
if (aBufLength - 2 < offset) {
// this subtable is not valid - beyond end of buffer
return 0;
}
const uint8_t* subtable = aBuf + offset;
const uint16_t format = ReadShortAt(subtable, SubtableOffsetFormat);
if (isSymbol(platformID, encodingID)) {
keepFormat = format;
*aTableOffset = offset;
if (aIsSymbolFont) {
*aIsSymbolFont = true;
}
break;
} else if (format == 4 &&
acceptableFormat4(platformID, encodingID, keepFormat)) {
keepFormat = format;
*aTableOffset = offset;
} else if ((format == 10 || format == 12 || format == 13) &&
acceptableUCS4Encoding(platformID, encodingID, keepFormat)) {
keepFormat = format;
*aTableOffset = offset;
if (platformID > PLATFORM_ID_UNICODE || !aUVSTableOffset ||
*aUVSTableOffset) {
break; // we don't want to try anything else when this format is
// available.
}
} else if (format == 14 && isUVSEncoding(platformID, encodingID) &&
aUVSTableOffset) {
*aUVSTableOffset = offset;
if (keepFormat == 10 || keepFormat == 12) {
break;
}
}
}
return keepFormat;
}
nsresult gfxFontUtils::ReadCMAP(const uint8_t* aBuf, uint32_t aBufLength,
gfxSparseBitSet& aCharacterMap,
uint32_t& aUVSOffset) {
uint32_t offset;
bool isSymbolFont;
uint32_t format = FindPreferredSubtable(aBuf, aBufLength, &offset,
&aUVSOffset, &isSymbolFont);
switch (format) {
case 4:
return ReadCMAPTableFormat4(aBuf + offset, aBufLength - offset,
aCharacterMap, isSymbolFont);
case 10:
return ReadCMAPTableFormat10(aBuf + offset, aBufLength - offset,
aCharacterMap);
case 12:
case 13:
return ReadCMAPTableFormat12or13(aBuf + offset, aBufLength - offset,
aCharacterMap);
default:
break;
}
return NS_ERROR_FAILURE;
}
#pragma pack(1)
typedef struct {
AutoSwap_PRUint16 format;
AutoSwap_PRUint16 length;
AutoSwap_PRUint16 language;
AutoSwap_PRUint16 segCountX2;
AutoSwap_PRUint16 searchRange;
AutoSwap_PRUint16 entrySelector;
AutoSwap_PRUint16 rangeShift;
AutoSwap_PRUint16 arrays[1];
} Format4Cmap;
typedef struct Format14Cmap {
AutoSwap_PRUint16 format;
AutoSwap_PRUint32 length;
AutoSwap_PRUint32 numVarSelectorRecords;
typedef struct {
AutoSwap_PRUint24 varSelector;
AutoSwap_PRUint32 defaultUVSOffset;
AutoSwap_PRUint32 nonDefaultUVSOffset;
} VarSelectorRecord;
VarSelectorRecord varSelectorRecords[1];
} Format14Cmap;
typedef struct NonDefUVSTable {
AutoSwap_PRUint32 numUVSMappings;
typedef struct {
AutoSwap_PRUint24 unicodeValue;
AutoSwap_PRUint16 glyphID;
} UVSMapping;
UVSMapping uvsMappings[1];
} NonDefUVSTable;
#pragma pack()
uint32_t gfxFontUtils::MapCharToGlyphFormat4(const uint8_t* aBuf,
uint32_t aLength, char16_t aCh) {
const Format4Cmap* cmap4 = reinterpret_cast<const Format4Cmap*>(aBuf);
uint16_t segCount = (uint16_t)(cmap4->segCountX2) / 2;
const AutoSwap_PRUint16* endCodes = &cmap4->arrays[0];
const AutoSwap_PRUint16* startCodes = &cmap4->arrays[segCount + 1];
const AutoSwap_PRUint16* idDelta = &startCodes[segCount];
const AutoSwap_PRUint16* idRangeOffset = &idDelta[segCount];
// Sanity-check that the fixed-size arrays don't exceed the buffer.
const uint8_t* const limit = aBuf + aLength;
if ((const uint8_t*)(&idRangeOffset[segCount]) > limit) {
return 0; // broken font, just bail out safely
}
// For most efficient binary search, we want to work on a range of segment
// indexes that is a power of 2 so that we can always halve it by shifting.
// So we find the largest power of 2 that is <= segCount.
// We will offset this range by segOffset so as to reach the end
// of the table, provided that doesn't put us beyond the target
// value from the outset.
uint32_t powerOf2 = mozilla::FindHighestBit(segCount);
uint32_t segOffset = segCount - powerOf2;
uint32_t idx = 0;
if (uint16_t(startCodes[segOffset]) <= aCh) {
idx = segOffset;
}
// Repeatedly halve the size of the range until we find the target group
while (powerOf2 > 1) {
powerOf2 >>= 1;
if (uint16_t(startCodes[idx + powerOf2]) <= aCh) {
idx += powerOf2;
}
}
if (aCh >= uint16_t(startCodes[idx]) && aCh <= uint16_t(endCodes[idx])) {
uint16_t result;
if (uint16_t(idRangeOffset[idx]) == 0) {
result = aCh;
} else {
uint16_t offset = aCh - uint16_t(startCodes[idx]);
const AutoSwap_PRUint16* glyphIndexTable =
(const AutoSwap_PRUint16*)((const char*)&idRangeOffset[idx] +
uint16_t(idRangeOffset[idx]));
if ((const uint8_t*)(glyphIndexTable + offset + 1) > limit) {
return 0; // broken font, just bail out safely
}
result = glyphIndexTable[offset];
}
// Note that this is unsigned 16-bit arithmetic, and may wrap around
// (which is required behavior per spec)
result += uint16_t(idDelta[idx]);
return result;
}
return 0;
}
uint32_t gfxFontUtils::MapCharToGlyphFormat10(const uint8_t* aBuf,
uint32_t aCh) {
const Format10CmapHeader* cmap10 =
reinterpret_cast<const Format10CmapHeader*>(aBuf);
uint32_t startChar = cmap10->startCharCode;
uint32_t numChars = cmap10->numChars;
if (aCh < startChar || aCh >= startChar + numChars) {
return 0;
}
const AutoSwap_PRUint16* glyphs =
reinterpret_cast<const AutoSwap_PRUint16*>(cmap10 + 1);
uint16_t glyph = glyphs[aCh - startChar];
return glyph;
}
uint32_t gfxFontUtils::MapCharToGlyphFormat12or13(const uint8_t* aBuf,
uint32_t aCh) {
// The only difference between formats 12 and 13 is the interpretation of
// the glyphId field. So the code here uses the same "Format12" structures,
// etc., to handle both subtable formats.
const Format12CmapHeader* cmap12 =
reinterpret_cast<const Format12CmapHeader*>(aBuf);
// We know that numGroups is within range for the subtable size
// because it was checked by ReadCMAPTableFormat12or13.
uint32_t numGroups = cmap12->numGroups;
// The array of groups immediately follows the subtable header.
const Format12Group* groups =
reinterpret_cast<const Format12Group*>(aBuf + sizeof(Format12CmapHeader));
// For most efficient binary search, we want to work on a range that
// is a power of 2 so that we can always halve it by shifting.
// So we find the largest power of 2 that is <= numGroups.
// We will offset this range by rangeOffset so as to reach the end
// of the table, provided that doesn't put us beyond the target
// value from the outset.
uint32_t powerOf2 = mozilla::FindHighestBit(numGroups);
uint32_t rangeOffset = numGroups - powerOf2;
uint32_t range = 0;
uint32_t startCharCode;
if (groups[rangeOffset].startCharCode <= aCh) {
range = rangeOffset;
}
// Repeatedly halve the size of the range until we find the target group
while (powerOf2 > 1) {
powerOf2 >>= 1;
if (groups[range + powerOf2].startCharCode <= aCh) {
range += powerOf2;
}
}
// Check if the character is actually present in the range and return
// the corresponding glyph ID. Here is where formats 12 and 13 interpret
// the startGlyphId (12) or glyphId (13) field differently
startCharCode = groups[range].startCharCode;
if (startCharCode <= aCh && groups[range].endCharCode >= aCh) {
return uint16_t(cmap12->format) == 12
? uint16_t(groups[range].startGlyphId) + aCh - startCharCode
: uint16_t(groups[range].startGlyphId);
}
// Else it's not present, so return the .notdef glyph
return 0;
}
namespace {
struct Format14CmapWrapper {
const Format14Cmap& mCmap14;
explicit Format14CmapWrapper(const Format14Cmap& cmap14) : mCmap14(cmap14) {}
uint32_t operator[](size_t index) const {
return mCmap14.varSelectorRecords[index].varSelector;
}
};
struct NonDefUVSTableWrapper {
const NonDefUVSTable& mTable;
explicit NonDefUVSTableWrapper(const NonDefUVSTable& table) : mTable(table) {}
uint32_t operator[](size_t index) const {
return mTable.uvsMappings[index].unicodeValue;
}
};
} // namespace
uint16_t gfxFontUtils::MapUVSToGlyphFormat14(const uint8_t* aBuf, uint32_t aCh,
uint32_t aVS) {
using mozilla::BinarySearch;
const Format14Cmap* cmap14 = reinterpret_cast<const Format14Cmap*>(aBuf);
size_t index;
if (!BinarySearch(Format14CmapWrapper(*cmap14), 0,
cmap14->numVarSelectorRecords, aVS, &index)) {
return 0;
}
const uint32_t nonDefUVSOffset =
cmap14->varSelectorRecords[index].nonDefaultUVSOffset;
if (!nonDefUVSOffset) {
return 0;
}
const NonDefUVSTable* table =
reinterpret_cast<const NonDefUVSTable*>(aBuf + nonDefUVSOffset);
if (BinarySearch(NonDefUVSTableWrapper(*table), 0, table->numUVSMappings, aCh,
&index)) {
return table->uvsMappings[index].glyphID;
}
return 0;
}
uint32_t gfxFontUtils::MapCharToGlyph(const uint8_t* aCmapBuf,
uint32_t aBufLength, uint32_t aUnicode,
uint32_t aVarSelector) {
uint32_t offset, uvsOffset;
bool isSymbolFont;
uint32_t format = FindPreferredSubtable(aCmapBuf, aBufLength, &offset,
&uvsOffset, &isSymbolFont);
uint32_t gid;
switch (format) {
case 4:
gid = aUnicode < UNICODE_BMP_LIMIT
? MapCharToGlyphFormat4(aCmapBuf + offset, aBufLength - offset,
char16_t(aUnicode))
: 0;
if (!gid && isSymbolFont) {
if (auto pua = MapLegacySymbolFontCharToPUA(aUnicode)) {
gid = MapCharToGlyphFormat4(aCmapBuf + offset, aBufLength - offset,
pua);
}
}
break;
case 10:
gid = MapCharToGlyphFormat10(aCmapBuf + offset, aUnicode);
break;
case 12:
case 13:
gid = MapCharToGlyphFormat12or13(aCmapBuf + offset, aUnicode);
break;
default:
NS_WARNING("unsupported cmap format, glyphs will be missing");
gid = 0;
}
if (aVarSelector && uvsOffset && gid) {
uint32_t varGID = gfxFontUtils::MapUVSToGlyphFormat14(
aCmapBuf + uvsOffset, aUnicode, aVarSelector);
if (!varGID) {
aUnicode = gfxFontUtils::GetUVSFallback(aUnicode, aVarSelector);
if (aUnicode) {
switch (format) {
case 4:
if (aUnicode < UNICODE_BMP_LIMIT) {
varGID = MapCharToGlyphFormat4(
aCmapBuf + offset, aBufLength - offset, char16_t(aUnicode));
}
break;
case 10:
varGID = MapCharToGlyphFormat10(aCmapBuf + offset, aUnicode);
break;
case 12:
case 13:
varGID = MapCharToGlyphFormat12or13(aCmapBuf + offset, aUnicode);
break;
}
}
}
if (varGID) {
gid = varGID;
}
// else the variation sequence was not supported, use default mapping
// of the character code alone
}
return gid;
}
void gfxFontUtils::ParseFontList(const nsACString& aFamilyList,
nsTArray<nsCString>& aFontList) {
const char kComma = ',';
// append each font name to the list
nsAutoCString fontname;
const char *p, *p_end;
aFamilyList.BeginReading(p);
aFamilyList.EndReading(p_end);
while (p < p_end) {
const char* nameStart = p;
while (++p != p_end && *p != kComma) /* nothing */
;
// pull out a single name and clean out leading/trailing whitespace
fontname = Substring(nameStart, p);
fontname.CompressWhitespace(true, true);
// append it to the list if it's not empty
if (!fontname.IsEmpty()) {
aFontList.AppendElement(fontname);
}
++p;
}
}
void gfxFontUtils::GetPrefsFontList(const char* aPrefName,
nsTArray<nsCString>& aFontList,
bool aLocalized) {
aFontList.Clear();
nsAutoCString fontlistValue;
nsresult rv = aLocalized
? Preferences::GetLocalizedCString(aPrefName, fontlistValue)
: Preferences::GetCString(aPrefName, fontlistValue);
if (NS_FAILED(rv)) {
return;
}
ParseFontList(fontlistValue, aFontList);
}
// produce a unique font name that is (1) a valid Postscript name and (2) less
// than 31 characters in length. Using AddFontMemResourceEx on Windows fails
// for names longer than 30 characters in length.
#define MAX_B64_LEN 32
nsresult gfxFontUtils::MakeUniqueUserFontName(nsAString& aName) {
nsCOMPtr<nsIUUIDGenerator> uuidgen =
do_GetService("@mozilla.org/uuid-generator;1");
NS_ENSURE_TRUE(uuidgen, NS_ERROR_OUT_OF_MEMORY);
nsID guid;
NS_ASSERTION(sizeof(guid) * 2 <= MAX_B64_LEN, "size of nsID has changed!");
nsresult rv = uuidgen->GenerateUUIDInPlace(&guid);
NS_ENSURE_SUCCESS(rv, rv);
char guidB64[MAX_B64_LEN] = {0};
if (!PL_Base64Encode(reinterpret_cast<char*>(&guid), sizeof(guid), guidB64))
return NS_ERROR_FAILURE;
// all b64 characters except for '/' are allowed in Postscript names, so
// convert / ==> -
char* p;
for (p = guidB64; *p; p++) {
if (*p == '/') *p = '-';
}
aName.AssignLiteral(u"uf");
aName.AppendASCII(guidB64);
return NS_OK;
}
// TrueType/OpenType table handling code
// need byte aligned structs
#pragma pack(1)
// name table stores set of name record structures, followed by
// large block containing all the strings. name record offset and length
// indicates the offset and length within that block.
// http://www.microsoft.com/typography/otspec/name.htm
struct NameRecordData {
uint32_t offset;
uint32_t length;
};
#pragma pack()
static bool IsValidSFNTVersion(uint32_t version) {
// normally 0x00010000, CFF-style OT fonts == 'OTTO' and Apple TT fonts =
// 'true' 'typ1' is also possible for old Type 1 fonts in a SFNT container but
// not supported
return version == 0x10000 || version == TRUETYPE_TAG('O', 'T', 'T', 'O') ||
version == TRUETYPE_TAG('t', 'r', 'u', 'e');
}
gfxUserFontType gfxFontUtils::DetermineFontDataType(const uint8_t* aFontData,
uint32_t aFontDataLength) {
// test for OpenType font data
// problem: EOT-Lite with 0x10000 length will look like TrueType!
if (aFontDataLength >= sizeof(SFNTHeader)) {
const SFNTHeader* sfntHeader =
reinterpret_cast<const SFNTHeader*>(aFontData);
uint32_t sfntVersion = sfntHeader->sfntVersion;
if (IsValidSFNTVersion(sfntVersion)) {
return GFX_USERFONT_OPENTYPE;
}
}
// test for WOFF or WOFF2
if (aFontDataLength >= sizeof(AutoSwap_PRUint32)) {
const AutoSwap_PRUint32* version =
reinterpret_cast<const AutoSwap_PRUint32*>(aFontData);
if (uint32_t(*version) == TRUETYPE_TAG('w', 'O', 'F', 'F')) {
return GFX_USERFONT_WOFF;
}
if (uint32_t(*version) == TRUETYPE_TAG('w', 'O', 'F', '2')) {
return GFX_USERFONT_WOFF2;
}
}
// tests for other formats here
return GFX_USERFONT_UNKNOWN;
}
static int DirEntryCmp(const void* aKey, const void* aItem) {
int32_t tag = *static_cast<const int32_t*>(aKey);
const TableDirEntry* entry = static_cast<const TableDirEntry*>(aItem);
return tag - int32_t(entry->tag);
}
/* static */
TableDirEntry* gfxFontUtils::FindTableDirEntry(const void* aFontData,
uint32_t aTableTag) {
const SFNTHeader* header = reinterpret_cast<const SFNTHeader*>(aFontData);
const TableDirEntry* dir = reinterpret_cast<const TableDirEntry*>(header + 1);
return static_cast<TableDirEntry*>(
bsearch(&aTableTag, dir, uint16_t(header->numTables),
sizeof(TableDirEntry), DirEntryCmp));
}
/* static */
hb_blob_t* gfxFontUtils::GetTableFromFontData(const void* aFontData,
uint32_t aTableTag) {
const TableDirEntry* dir = FindTableDirEntry(aFontData, aTableTag);
if (dir) {
return hb_blob_create(
reinterpret_cast<const char*>(aFontData) + dir->offset, dir->length,
HB_MEMORY_MODE_READONLY, nullptr, nullptr);
}
return nullptr;
}
nsresult gfxFontUtils::RenameFont(const nsAString& aName,
const uint8_t* aFontData,
uint32_t aFontDataLength,
FallibleTArray<uint8_t>* aNewFont) {
NS_ASSERTION(aNewFont, "null font data array");
uint64_t dataLength(aFontDataLength);
// new name table
static const uint32_t neededNameIDs[] = {NAME_ID_FAMILY, NAME_ID_STYLE,
NAME_ID_UNIQUE, NAME_ID_FULL,
NAME_ID_POSTSCRIPT};
// calculate new name table size
uint16_t nameCount = ArrayLength(neededNameIDs);
// leave room for null-terminator
uint32_t nameStrLength = (aName.Length() + 1) * sizeof(char16_t);
if (nameStrLength > 65535) {
// The name length _in bytes_ must fit in an unsigned short field;
// therefore, a name longer than this cannot be used.
return NS_ERROR_FAILURE;
}
// round name table size up to 4-byte multiple
uint32_t nameTableSize =
(sizeof(NameHeader) + sizeof(NameRecord) * nameCount + nameStrLength +
3) &
~3;
if (dataLength + nameTableSize > UINT32_MAX) return NS_ERROR_FAILURE;
// bug 505386 - need to handle unpadded font length
uint32_t paddedFontDataSize = (aFontDataLength + 3) & ~3;
uint32_t adjFontDataSize = paddedFontDataSize + nameTableSize;
// create new buffer: old font data plus new name table
if (!aNewFont->AppendElements(adjFontDataSize, fallible))
return NS_ERROR_OUT_OF_MEMORY;
// copy the old font data
uint8_t* newFontData = reinterpret_cast<uint8_t*>(aNewFont->Elements());
// null the last four bytes in case the font length is not a multiple of 4
memset(newFontData + aFontDataLength, 0,
paddedFontDataSize - aFontDataLength);
// copy font data
memcpy(newFontData, aFontData, aFontDataLength);
// null out the last 4 bytes for checksum calculations
memset(newFontData + adjFontDataSize - 4, 0, 4);
NameHeader* nameHeader =
reinterpret_cast<NameHeader*>(newFontData + paddedFontDataSize);
// -- name header
nameHeader->format = 0;
nameHeader->count = nameCount;
nameHeader->stringOffset =
sizeof(NameHeader) + nameCount * sizeof(NameRecord);
// -- name records
uint32_t i;
NameRecord* nameRecord = reinterpret_cast<NameRecord*>(nameHeader + 1);
for (i = 0; i < nameCount; i++, nameRecord++) {
nameRecord->platformID = PLATFORM_ID_MICROSOFT;
nameRecord->encodingID = ENCODING_ID_MICROSOFT_UNICODEBMP;
nameRecord->languageID = LANG_ID_MICROSOFT_EN_US;
nameRecord->nameID = neededNameIDs[i];
nameRecord->offset = 0;
nameRecord->length = nameStrLength;
}
// -- string data, located after the name records, stored in big-endian form
char16_t* strData = reinterpret_cast<char16_t*>(nameRecord);
mozilla::NativeEndian::copyAndSwapToBigEndian(strData, aName.BeginReading(),
aName.Length());
strData[aName.Length()] = 0; // add null termination
// adjust name table header to point to the new name table
SFNTHeader* sfntHeader = reinterpret_cast<SFNTHeader*>(newFontData);
// table directory entries begin immediately following SFNT header
TableDirEntry* dirEntry =
FindTableDirEntry(newFontData, TRUETYPE_TAG('n', 'a', 'm', 'e'));
// function only called if font validates, so this should always be true
MOZ_ASSERT(dirEntry, "attempt to rename font with no name table");
uint32_t numTables = sfntHeader->numTables;
// note: dirEntry now points to 'name' table record
// recalculate name table checksum
uint32_t checkSum = 0;
AutoSwap_PRUint32* nameData =
reinterpret_cast<AutoSwap_PRUint32*>(nameHeader);
AutoSwap_PRUint32* nameDataEnd = nameData + (nameTableSize >> 2);
while (nameData < nameDataEnd) checkSum = checkSum + *nameData++;
// adjust name table entry to point to new name table
dirEntry->offset = paddedFontDataSize;
dirEntry->length = nameTableSize;
dirEntry->checkSum = checkSum;
// fix up checksums
uint32_t checksum = 0;
// checksum for font = (checksum of header) + (checksum of tables)
uint32_t headerLen = sizeof(SFNTHeader) + sizeof(TableDirEntry) * numTables;
const AutoSwap_PRUint32* headerData =
reinterpret_cast<const AutoSwap_PRUint32*>(newFontData);
// header length is in bytes, checksum calculated in longwords
for (i = 0; i < (headerLen >> 2); i++, headerData++) {
checksum += *headerData;
}
uint32_t headOffset = 0;
dirEntry = reinterpret_cast<TableDirEntry*>(newFontData + sizeof(SFNTHeader));
for (i = 0; i < numTables; i++, dirEntry++) {
if (dirEntry->tag == TRUETYPE_TAG('h', 'e', 'a', 'd')) {
headOffset = dirEntry->offset;
}
checksum += dirEntry->checkSum;
}
NS_ASSERTION(headOffset != 0, "no head table for font");
HeadTable* headData = reinterpret_cast<HeadTable*>(newFontData + headOffset);
headData->checkSumAdjustment = HeadTable::HEAD_CHECKSUM_CALC_CONST - checksum;
return NS_OK;
}
// This is only called after the basic validity of the downloaded sfnt
// data has been checked, so it should never fail to find the name table
// (though it might fail to read it, if memory isn't available);
// other checks here are just for extra paranoia.
nsresult gfxFontUtils::GetFullNameFromSFNT(const uint8_t* aFontData,
uint32_t aLength,
nsACString& aFullName) {
aFullName = "(MISSING NAME)"; // should always get replaced
const TableDirEntry* dirEntry =
FindTableDirEntry(aFontData, TRUETYPE_TAG('n', 'a', 'm', 'e'));
// should never fail, as we're only called after font validation succeeded
NS_ENSURE_TRUE(dirEntry, NS_ERROR_NOT_AVAILABLE);
uint32_t len = dirEntry->length;
NS_ENSURE_TRUE(aLength > len && aLength - len >= dirEntry->offset,
NS_ERROR_UNEXPECTED);
AutoHBBlob nameBlob(hb_blob_create((const char*)aFontData + dirEntry->offset,
len, HB_MEMORY_MODE_READONLY, nullptr,
nullptr));
nsresult rv = GetFullNameFromTable(nameBlob, aFullName);
return rv;
}
nsresult gfxFontUtils::GetFullNameFromTable(hb_blob_t* aNameTable,
nsACString& aFullName) {
nsAutoCString name;
nsresult rv = gfxFontUtils::ReadCanonicalName(
aNameTable, gfxFontUtils::NAME_ID_FULL, name);
if (NS_SUCCEEDED(rv) && !name.IsEmpty()) {
aFullName = name;
return NS_OK;
}
rv = gfxFontUtils::ReadCanonicalName(aNameTable, gfxFontUtils::NAME_ID_FAMILY,
name);
if (NS_SUCCEEDED(rv) && !name.IsEmpty()) {
nsAutoCString styleName;
rv = gfxFontUtils::ReadCanonicalName(
aNameTable, gfxFontUtils::NAME_ID_STYLE, styleName);
if (NS_SUCCEEDED(rv) && !styleName.IsEmpty()) {
name.Append(' ');
name.Append(styleName);
aFullName = name;
}
return NS_OK;
}
return NS_ERROR_NOT_AVAILABLE;
}
nsresult gfxFontUtils::GetFamilyNameFromTable(hb_blob_t* aNameTable,
nsACString& aFamilyName) {
nsAutoCString name;
nsresult rv = gfxFontUtils::ReadCanonicalName(
aNameTable, gfxFontUtils::NAME_ID_FAMILY, name);
if (NS_SUCCEEDED(rv) && !name.IsEmpty()) {
aFamilyName = name;
return NS_OK;
}
return NS_ERROR_NOT_AVAILABLE;
}
enum {
#if defined(XP_MACOSX)
CANONICAL_LANG_ID = gfxFontUtils::LANG_ID_MAC_ENGLISH,
PLATFORM_ID = gfxFontUtils::PLATFORM_ID_MAC
#else
CANONICAL_LANG_ID = gfxFontUtils::LANG_ID_MICROSOFT_EN_US,
PLATFORM_ID = gfxFontUtils::PLATFORM_ID_MICROSOFT
#endif
};
nsresult gfxFontUtils::ReadNames(const char* aNameData, uint32_t aDataLen,
uint32_t aNameID, int32_t aPlatformID,
nsTArray<nsCString>& aNames) {
return ReadNames(aNameData, aDataLen, aNameID, LANG_ALL, aPlatformID, aNames);
}
nsresult gfxFontUtils::ReadCanonicalName(hb_blob_t* aNameTable,
uint32_t aNameID, nsCString& aName) {
uint32_t nameTableLen;
const char* nameTable = hb_blob_get_data(aNameTable, &nameTableLen);
return ReadCanonicalName(nameTable, nameTableLen, aNameID, aName);
}
nsresult gfxFontUtils::ReadCanonicalName(const char* aNameData,
uint32_t aDataLen, uint32_t aNameID,
nsCString& aName) {
nsresult rv;
nsTArray<nsCString> names;
// first, look for the English name (this will succeed 99% of the time)
rv = ReadNames(aNameData, aDataLen, aNameID, CANONICAL_LANG_ID, PLATFORM_ID,
names);
NS_ENSURE_SUCCESS(rv, rv);
// otherwise, grab names for all languages
if (names.Length() == 0) {
rv = ReadNames(aNameData, aDataLen, aNameID, LANG_ALL, PLATFORM_ID, names);
NS_ENSURE_SUCCESS(rv, rv);
}
#if defined(XP_MACOSX)
// may be dealing with font that only has Microsoft name entries
if (names.Length() == 0) {
rv = ReadNames(aNameData, aDataLen, aNameID, LANG_ID_MICROSOFT_EN_US,
PLATFORM_ID_MICROSOFT, names);
NS_ENSURE_SUCCESS(rv, rv);
// getting really desperate now, take anything!
if (names.Length() == 0) {
rv = ReadNames(aNameData, aDataLen, aNameID, LANG_ALL,
PLATFORM_ID_MICROSOFT, names);
NS_ENSURE_SUCCESS(rv, rv);
}
}
#endif
// return the first name (99.9% of the time names will
// contain a single English name)
if (names.Length()) {
aName.Assign(names[0]);
return NS_OK;
}
return NS_ERROR_FAILURE;
}
// Charsets to use for decoding Mac platform font names.
// This table is sorted by {encoding, language}, with the wildcard "ANY" being
// greater than any defined values for each field; we use a binary search on
// both fields, and fall back to matching only encoding if necessary
// Some "redundant" entries for specific combinations are included such as
// encoding=roman, lang=english, in order that common entries will be found
// on the first search.
const uint16_t ANY = 0xffff;
const gfxFontUtils::MacFontNameCharsetMapping
gfxFontUtils::gMacFontNameCharsets[] = {
{ENCODING_ID_MAC_ROMAN, LANG_ID_MAC_ENGLISH, MACINTOSH_ENCODING},
{ENCODING_ID_MAC_ROMAN, LANG_ID_MAC_ICELANDIC, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ROMAN, LANG_ID_MAC_TURKISH, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ROMAN, LANG_ID_MAC_POLISH, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ROMAN, LANG_ID_MAC_ROMANIAN, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ROMAN, LANG_ID_MAC_CZECH, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ROMAN, LANG_ID_MAC_SLOVAK, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ROMAN, ANY, MACINTOSH_ENCODING},
{ENCODING_ID_MAC_JAPANESE, LANG_ID_MAC_JAPANESE, SHIFT_JIS_ENCODING},
{ENCODING_ID_MAC_JAPANESE, ANY, SHIFT_JIS_ENCODING},
{ENCODING_ID_MAC_TRAD_CHINESE, LANG_ID_MAC_TRAD_CHINESE, BIG5_ENCODING},
{ENCODING_ID_MAC_TRAD_CHINESE, ANY, BIG5_ENCODING},
{ENCODING_ID_MAC_KOREAN, LANG_ID_MAC_KOREAN, EUC_KR_ENCODING},
{ENCODING_ID_MAC_KOREAN, ANY, EUC_KR_ENCODING},
{ENCODING_ID_MAC_ARABIC, LANG_ID_MAC_ARABIC, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ARABIC, LANG_ID_MAC_URDU, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ARABIC, LANG_ID_MAC_FARSI, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_ARABIC, ANY, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_HEBREW, LANG_ID_MAC_HEBREW, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_HEBREW, ANY, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_GREEK, ANY, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_CYRILLIC, ANY, X_MAC_CYRILLIC_ENCODING},
{ENCODING_ID_MAC_DEVANAGARI, ANY, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_GURMUKHI, ANY, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_GUJARATI, ANY, X_USER_DEFINED_ENCODING},
{ENCODING_ID_MAC_SIMP_CHINESE, LANG_ID_MAC_SIMP_CHINESE,
GB18030_ENCODING},
{ENCODING_ID_MAC_SIMP_CHINESE, ANY, GB18030_ENCODING}};
const Encoding* gfxFontUtils::gISOFontNameCharsets[] = {
/* 0 */ WINDOWS_1252_ENCODING, /* US-ASCII */
/* 1 */ nullptr, /* spec says "ISO 10646" but does not specify encoding
form! */
/* 2 */ WINDOWS_1252_ENCODING /* ISO-8859-1 */
};
const Encoding* gfxFontUtils::gMSFontNameCharsets[] = {
/* [0] ENCODING_ID_MICROSOFT_SYMBOL */ UTF_16BE_ENCODING,
/* [1] ENCODING_ID_MICROSOFT_UNICODEBMP */ UTF_16BE_ENCODING,
/* [2] ENCODING_ID_MICROSOFT_SHIFTJIS */ SHIFT_JIS_ENCODING,
/* [3] ENCODING_ID_MICROSOFT_PRC */ nullptr,
/* [4] ENCODING_ID_MICROSOFT_BIG5 */ BIG5_ENCODING,
/* [5] ENCODING_ID_MICROSOFT_WANSUNG */ nullptr,
/* [6] ENCODING_ID_MICROSOFT_JOHAB */ nullptr,
/* [7] reserved */ nullptr,
/* [8] reserved */ nullptr,
/* [9] reserved */ nullptr,
/*[10] ENCODING_ID_MICROSOFT_UNICODEFULL */ UTF_16BE_ENCODING};
struct MacCharsetMappingComparator {
typedef gfxFontUtils::MacFontNameCharsetMapping MacFontNameCharsetMapping;
const MacFontNameCharsetMapping& mSearchValue;
explicit MacCharsetMappingComparator(
const MacFontNameCharsetMapping& aSearchValue)
: mSearchValue(aSearchValue) {}
int operator()(const MacFontNameCharsetMapping& aEntry) const {
if (mSearchValue < aEntry) {
return -1;
}
if (aEntry < mSearchValue) {
return 1;
}
return 0;
}
};
// Return the Encoding object we should use to decode a font name
// given the name table attributes.
// Special return values:
// X_USER_DEFINED_ENCODING One of Mac legacy encodings that is not a part
// of Encoding Standard
// nullptr unknown charset, do not attempt conversion
const Encoding* gfxFontUtils::GetCharsetForFontName(uint16_t aPlatform,
uint16_t aScript,
uint16_t aLanguage) {
switch (aPlatform) {
case PLATFORM_ID_UNICODE:
return UTF_16BE_ENCODING;
case PLATFORM_ID_MAC: {
MacFontNameCharsetMapping searchValue = {aScript, aLanguage, nullptr};
for (uint32_t i = 0; i < 2; ++i) {
size_t idx;
if (BinarySearchIf(gMacFontNameCharsets, 0,
ArrayLength(gMacFontNameCharsets),
MacCharsetMappingComparator(searchValue), &idx)) {
return gMacFontNameCharsets[idx].mEncoding;
}
// no match, so try again finding one in any language
searchValue.mLanguage = ANY;
}
} break;
case PLATFORM_ID_ISO:
if (aScript < ArrayLength(gISOFontNameCharsets)) {
return gISOFontNameCharsets[aScript];
}
break;
case PLATFORM_ID_MICROSOFT:
if (aScript < ArrayLength(gMSFontNameCharsets)) {
return gMSFontNameCharsets[aScript];
}
break;
}
return nullptr;
}
template <int N>
static bool StartsWith(const nsACString& string, const char (&prefix)[N]) {
if (N - 1 > string.Length()) {
return false;
}
return memcmp(string.Data(), prefix, N - 1) == 0;
}
// convert a raw name from the name table to an nsString, if possible;
// return value indicates whether conversion succeeded
bool gfxFontUtils::DecodeFontName(const char* aNameData, int32_t aByteLen,
uint32_t aPlatformCode, uint32_t aScriptCode,
uint32_t aLangCode, nsACString& aName) {
if (aByteLen <= 0) {
NS_WARNING("empty font name");
aName.SetLength(0);
return true;
}
auto encoding = GetCharsetForFontName(aPlatformCode, aScriptCode, aLangCode);
if (!encoding) {
// nullptr -> unknown charset
#ifdef DEBUG
char warnBuf[128];
if (aByteLen > 64) aByteLen = 64;
SprintfLiteral(warnBuf,
"skipping font name, unknown charset %d:%d:%d for <%.*s>",
aPlatformCode, aScriptCode, aLangCode, aByteLen, aNameData);
NS_WARNING(warnBuf);
#endif
return false;
}
if (encoding == X_USER_DEFINED_ENCODING) {
#ifdef XP_DARWIN
// Special case for macOS only: support legacy Mac encodings
// that aren't part of the Encoding Standard.
if (aPlatformCode == PLATFORM_ID_MAC) {
CFStringRef str =
CFStringCreateWithBytes(kCFAllocatorDefault, (const UInt8*)aNameData,
aByteLen, aScriptCode, false);
if (str) {
CFIndex length = CFStringGetLength(str);
nsAutoString name16;
name16.SetLength(length);
CFStringGetCharacters(str, CFRangeMake(0, length),
(UniChar*)name16.BeginWriting());
CFRelease(str);
CopyUTF16toUTF8(name16, aName);
return true;
}
}
#endif
NS_WARNING("failed to get the decoder for a font name string");
return false;
}
auto rv = encoding->DecodeWithoutBOMHandling(
nsDependentCSubstring(aNameData, aByteLen), aName);
return NS_SUCCEEDED(rv);
}
nsresult gfxFontUtils::ReadNames(const char* aNameData, uint32_t aDataLen,
uint32_t aNameID, int32_t aLangID,
int32_t aPlatformID,
nsTArray<nsCString>& aNames) {
NS_ASSERTION(aDataLen != 0, "null name table");
if (!aDataLen) {
return NS_ERROR_FAILURE;
}
// -- name table data
const NameHeader* nameHeader = reinterpret_cast<const NameHeader*>(aNameData);
uint32_t nameCount = nameHeader->count;
// -- sanity check the number of name records
if (uint64_t(nameCount) * sizeof(NameRecord) > aDataLen) {
NS_WARNING("invalid font (name table data)");
return NS_ERROR_FAILURE;
}
// -- iterate through name records
const NameRecord* nameRecord =
reinterpret_cast<const NameRecord*>(aNameData + sizeof(NameHeader));
uint64_t nameStringsBase = uint64_t(nameHeader->stringOffset);
uint32_t i;
for (i = 0; i < nameCount; i++, nameRecord++) {
uint32_t platformID;
// skip over unwanted nameID's
if (uint32_t(nameRecord->nameID) != aNameID) {
continue;
}
// skip over unwanted platform data
platformID = nameRecord->platformID;
if (aPlatformID != PLATFORM_ALL && platformID != uint32_t(aPlatformID)) {
continue;
}
// skip over unwanted languages
if (aLangID != LANG_ALL &&
uint32_t(nameRecord->languageID) != uint32_t(aLangID)) {
continue;
}
// add name to names array
// -- calculate string location
uint32_t namelen = nameRecord->length;
uint32_t nameoff =
nameRecord->offset; // offset from base of string storage
if (nameStringsBase + uint64_t(nameoff) + uint64_t(namelen) > aDataLen) {
NS_WARNING("invalid font (name table strings)");
return NS_ERROR_FAILURE;
}
// -- decode if necessary and make nsString
nsAutoCString name;
DecodeFontName(aNameData + nameStringsBase + nameoff, namelen, platformID,
uint32_t(nameRecord->encodingID),
uint32_t(nameRecord->languageID), name);
uint32_t k, numNames;
bool foundName = false;
numNames = aNames.Length();
for (k = 0; k < numNames; k++) {
if (name.Equals(aNames[k])) {
foundName = true;
break;
}
}
if (!foundName) aNames.AppendElement(name);
}
return NS_OK;
}
void gfxFontUtils::GetVariationData(
gfxFontEntry* aFontEntry, nsTArray<gfxFontVariationAxis>* aAxes,
nsTArray<gfxFontVariationInstance>* aInstances) {
MOZ_ASSERT(!aAxes || aAxes->IsEmpty());
MOZ_ASSERT(!aInstances || aInstances->IsEmpty());
if (!aFontEntry->HasVariations()) {
return;
}
// Some platforms don't offer a simple API to return the list of instances,
// so we have to interpret the 'fvar' table ourselves.
// https://www.microsoft.com/typography/otspec/fvar.htm#fvarHeader
struct FvarHeader {
AutoSwap_PRUint16 majorVersion;
AutoSwap_PRUint16 minorVersion;
AutoSwap_PRUint16 axesArrayOffset;
AutoSwap_PRUint16 reserved;
AutoSwap_PRUint16 axisCount;
AutoSwap_PRUint16 axisSize;
AutoSwap_PRUint16 instanceCount;
AutoSwap_PRUint16 instanceSize;
};
// https://www.microsoft.com/typography/otspec/fvar.htm#variationAxisRecord
struct AxisRecord {
AutoSwap_PRUint32 axisTag;
AutoSwap_PRInt32 minValue;
AutoSwap_PRInt32 defaultValue;
AutoSwap_PRInt32 maxValue;
AutoSwap_PRUint16 flags;
AutoSwap_PRUint16 axisNameID;
};
const uint16_t HIDDEN_AXIS = 0x0001; // AxisRecord flags value
// https://www.microsoft.com/typography/otspec/fvar.htm#instanceRecord
struct InstanceRecord {
AutoSwap_PRUint16 subfamilyNameID;
AutoSwap_PRUint16 flags;
AutoSwap_PRInt32 coordinates[1]; // variable-size array [axisCount]
// The variable-length 'coordinates' array may be followed by an
// optional extra field 'postScriptNameID'. We can't directly
// represent this in the struct, because its offset varies depending
// on the number of axes present.
// (Not currently used by our code here anyhow.)
// AutoSwap_PRUint16 postScriptNameID;
};
// Load the two font tables we need as harfbuzz blobs; if either is absent,
// just bail out.
AutoHBBlob fvarTable(
aFontEntry->GetFontTable(TRUETYPE_TAG('f', 'v', 'a', 'r')));
AutoHBBlob nameTable(
aFontEntry->GetFontTable(TRUETYPE_TAG('n', 'a', 'm', 'e')));
if (!fvarTable || !nameTable) {
return;
}
unsigned int len;
const char* data = hb_blob_get_data(fvarTable, &len);
if (len < sizeof(FvarHeader)) {
return;
}
// Read the fields of the table header; bail out if it looks broken.
auto fvar = reinterpret_cast<const FvarHeader*>(data);
if (uint16_t(fvar->majorVersion) != 1 || uint16_t(fvar->minorVersion) != 0 ||
uint16_t(fvar->reserved) != 2) {
return;
}
uint16_t axisCount = fvar->axisCount;
uint16_t axisSize = fvar->axisSize;
uint16_t instanceCount = fvar->instanceCount;
uint16_t instanceSize = fvar->instanceSize;
if (axisCount ==
0 || // no axes?
// https://www.microsoft.com/typography/otspec/fvar.htm#axisSize
axisSize != 20 || // required value for current table version
// https://www.microsoft.com/typography/otspec/fvar.htm#instanceSize
(instanceSize != axisCount * sizeof(int32_t) + 4 &&
instanceSize != axisCount * sizeof(int32_t) + 6)) {
return;
}
// Check that axis array will not exceed table size
uint16_t axesOffset = fvar->axesArrayOffset;
if (axesOffset + uint32_t(axisCount) * axisSize > len) {
return;
}
// Get pointer to the array of axis records
auto axes = reinterpret_cast<const AxisRecord*>(data + axesOffset);
// Get address of instance array, and check it doesn't overflow table size.
// https://www.microsoft.com/typography/otspec/fvar.htm#axisAndInstanceArrays
auto instData = data + axesOffset + axisCount * axisSize;
if (instData + uint32_t(instanceCount) * instanceSize > data + len) {
return;
}
if (aInstances) {
aInstances->SetCapacity(instanceCount);
for (unsigned i = 0; i < instanceCount; ++i, instData += instanceSize) {
// Typed pointer to the current instance record, to read its fields.
auto inst = reinterpret_cast<const InstanceRecord*>(instData);
// Pointer to the coordinates array within the instance record.
// This array has axisCount elements, and is included in instanceSize
// (which depends on axisCount, and was validated above) so we know
// access to coords[j] below will not be outside the table bounds.
auto coords = &inst->coordinates[0];
gfxFontVariationInstance instance;
uint16_t nameID = inst->subfamilyNameID;
nsresult rv = ReadCanonicalName(nameTable, nameID, instance.mName);
if (NS_FAILED(rv)) {
// If no name was available for the instance, ignore it.
continue;
}
instance.mValues.SetCapacity(axisCount);
for (unsigned j = 0; j < axisCount; ++j) {
gfxFontVariationValue value = {axes[j].axisTag,
int32_t(coords[j]) / 65536.0f};
instance.mValues.AppendElement(value);
}
aInstances->AppendElement(std::move(instance));
}
}
if (aAxes) {
aAxes->SetCapacity(axisCount);
for (unsigned i = 0; i < axisCount; ++i) {
if (uint16_t(axes[i].flags) & HIDDEN_AXIS) {
continue;
}
gfxFontVariationAxis axis;
axis.mTag = axes[i].axisTag;
uint16_t nameID = axes[i].axisNameID;
nsresult rv = ReadCanonicalName(nameTable, nameID, axis.mName);
if (NS_FAILED(rv)) {
axis.mName.Truncate(0);
}
// Convert values from 16.16 fixed-point to float
axis.mMinValue = int32_t(axes[i].minValue) / 65536.0f;
axis.mDefaultValue = int32_t(axes[i].defaultValue) / 65536.0f;
axis.mMaxValue = int32_t(axes[i].maxValue) / 65536.0f;
aAxes->AppendElement(axis);
}
}
}
void gfxFontUtils::ReadOtherFamilyNamesForFace(
const nsACString& aFamilyName, const char* aNameData, uint32_t aDataLength,
nsTArray<nsCString>& aOtherFamilyNames, bool useFullName) {
const NameHeader* nameHeader = reinterpret_cast<const NameHeader*>(aNameData);
uint32_t nameCount = nameHeader->count;
if (nameCount * sizeof(NameRecord) > aDataLength) {
NS_WARNING("invalid font (name records)");
return;
}
const NameRecord* nameRecord =
reinterpret_cast<const NameRecord*>(aNameData + sizeof(NameHeader));
uint32_t stringsBase = uint32_t(nameHeader->stringOffset);
for (uint32_t i = 0; i < nameCount; i++, nameRecord++) {
uint32_t nameLen = nameRecord->length;
uint32_t nameOff =
nameRecord->offset; // offset from base of string storage
if (stringsBase + nameOff + nameLen > aDataLength) {
NS_WARNING("invalid font (name table strings)");
return;
}
uint16_t nameID = nameRecord->nameID;
if ((useFullName && nameID == NAME_ID_FULL) ||
(!useFullName &&
(nameID == NAME_ID_FAMILY || nameID == NAME_ID_PREFERRED_FAMILY))) {
nsAutoCString otherFamilyName;
bool ok = DecodeFontName(
aNameData + stringsBase + nameOff, nameLen,
uint32_t(nameRecord->platformID), uint32_t(nameRecord->encodingID),
uint32_t(nameRecord->languageID), otherFamilyName);
// add if not same as canonical family name
if (ok && otherFamilyName != aFamilyName &&
!aOtherFamilyNames.Contains(otherFamilyName)) {
aOtherFamilyNames.AppendElement(otherFamilyName);
}
}
}
}
#ifdef XP_WIN
/* static */
bool gfxFontUtils::IsCffFont(const uint8_t* aFontData) {
// this is only called after aFontData has passed basic validation,
// so we know there is enough data present to allow us to read the version!
const SFNTHeader* sfntHeader = reinterpret_cast<const SFNTHeader*>(aFontData);
return (sfntHeader->sfntVersion == TRUETYPE_TAG('O', 'T', 'T', 'O'));
}
#endif
/* static */ bool gfxFontUtils::IsInServoTraversal() {
if (NS_IsMainThread()) {
return ServoStyleSet::IsInServoTraversal();
}
if (dom::GetCurrentThreadWorkerPrivate()) {
return false;
}
// The only permissible threads are the main thread, the worker thread, the
// servo threads. If the latter, we must be traversing.
bool traversing = ServoStyleSet::IsInServoTraversal();
MOZ_ASSERT(traversing);
return traversing;
}
/* static */ ServoStyleSet* gfxFontUtils::CurrentServoStyleSet() {
// If we are on a worker thread, we must not check for the current set since
// the main/servo threads may be busy in parallel.
if (dom::GetCurrentThreadWorkerPrivate()) {
return nullptr;
}
return ServoStyleSet::Current();
}
#ifdef DEBUG
/* static */ void gfxFontUtils::AssertSafeThreadOrServoFontMetricsLocked() {
if (!dom::GetCurrentThreadWorkerPrivate()) {
AssertIsMainThreadOrServoFontMetricsLocked();
}
}
#endif
#undef acceptablePlatform
#undef isSymbol
#undef isUVSEncoding
#undef LOG
#undef LOG_ENABLED
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