mirror of
https://github.com/classilla/tenfourfox.git
synced 2024-06-09 11:29:39 +00:00
471 lines
16 KiB
C++
471 lines
16 KiB
C++
// Copyright 2014 Google Inc. All Rights Reserved.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
//
|
|
// Library for converting TTF format font files to their WOFF2 versions.
|
|
|
|
#include "./woff2_enc.h"
|
|
|
|
#include <stdlib.h>
|
|
#include <complex>
|
|
#include <cstring>
|
|
#include <limits>
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
#include "./brotli/encode.h"
|
|
#include "./buffer.h"
|
|
#include "./font.h"
|
|
#include "./normalize.h"
|
|
#include "./round.h"
|
|
#include "./store_bytes.h"
|
|
#include "./table_tags.h"
|
|
#include "./transform.h"
|
|
#include "./variable_length.h"
|
|
#include "./woff2_common.h"
|
|
|
|
namespace woff2 {
|
|
|
|
namespace {
|
|
|
|
|
|
using std::string;
|
|
using std::vector;
|
|
|
|
|
|
const size_t kWoff2HeaderSize = 48;
|
|
const size_t kWoff2EntrySize = 20;
|
|
|
|
bool Compress(const uint8_t* data, const size_t len, uint8_t* result,
|
|
uint32_t* result_len, BrotliEncoderMode mode, int quality) {
|
|
size_t compressed_len = *result_len;
|
|
if (BrotliEncoderCompress(quality, BROTLI_DEFAULT_WINDOW, mode, len, data,
|
|
&compressed_len, result) == 0) {
|
|
return false;
|
|
}
|
|
*result_len = compressed_len;
|
|
return true;
|
|
}
|
|
|
|
bool Woff2Compress(const uint8_t* data, const size_t len,
|
|
uint8_t* result, uint32_t* result_len,
|
|
int quality) {
|
|
return Compress(data, len, result, result_len,
|
|
BROTLI_MODE_FONT, quality);
|
|
}
|
|
|
|
bool TextCompress(const uint8_t* data, const size_t len,
|
|
uint8_t* result, uint32_t* result_len,
|
|
int quality) {
|
|
return Compress(data, len, result, result_len,
|
|
BROTLI_MODE_TEXT, quality);
|
|
}
|
|
|
|
int KnownTableIndex(uint32_t tag) {
|
|
for (int i = 0; i < 63; ++i) {
|
|
if (tag == kKnownTags[i]) return i;
|
|
}
|
|
return 63;
|
|
}
|
|
|
|
void StoreTableEntry(const Table& table, size_t* offset, uint8_t* dst) {
|
|
uint8_t flag_byte = (table.flags & 0xC0) | KnownTableIndex(table.tag);
|
|
dst[(*offset)++] = flag_byte;
|
|
// The index here is treated as a set of flag bytes because
|
|
// bits 6 and 7 of the byte are reserved for future use as flags.
|
|
// 0x3f or 63 means an arbitrary table tag.
|
|
if ((flag_byte & 0x3f) == 0x3f) {
|
|
StoreU32(table.tag, offset, dst);
|
|
}
|
|
StoreBase128(table.src_length, offset, dst);
|
|
if ((table.flags & kWoff2FlagsTransform) != 0) {
|
|
StoreBase128(table.transform_length, offset, dst);
|
|
}
|
|
}
|
|
|
|
size_t TableEntrySize(const Table& table) {
|
|
uint8_t flag_byte = KnownTableIndex(table.tag);
|
|
size_t size = ((flag_byte & 0x3f) != 0x3f) ? 1 : 5;
|
|
size += Base128Size(table.src_length);
|
|
if ((table.flags & kWoff2FlagsTransform) != 0) {
|
|
size += Base128Size(table.transform_length);
|
|
}
|
|
return size;
|
|
}
|
|
|
|
size_t ComputeWoff2Length(const FontCollection& font_collection,
|
|
const std::vector<Table>& tables,
|
|
std::map<std::pair<uint32_t, uint32_t>, uint16_t>
|
|
index_by_tag_offset,
|
|
size_t compressed_data_length,
|
|
size_t extended_metadata_length) {
|
|
size_t size = kWoff2HeaderSize;
|
|
|
|
for (const auto& table : tables) {
|
|
size += TableEntrySize(table);
|
|
}
|
|
|
|
// for collections only, collection tables
|
|
if (font_collection.flavor == kTtcFontFlavor) {
|
|
size += 4; // UInt32 Version of TTC Header
|
|
size += Size255UShort(font_collection.fonts.size()); // 255UInt16 numFonts
|
|
|
|
size += 4 * font_collection.fonts.size(); // UInt32 flavor for each
|
|
|
|
for (const auto& font : font_collection.fonts) {
|
|
size += Size255UShort(font.tables.size()); // 255UInt16 numTables
|
|
for (const auto& entry : font.tables) {
|
|
const Font::Table& table = entry.second;
|
|
// no collection entry for xform table
|
|
if (table.tag & 0x80808080) continue;
|
|
|
|
std::pair<uint32_t, uint32_t> tag_offset(table.tag, table.offset);
|
|
uint16_t table_index = index_by_tag_offset[tag_offset];
|
|
size += Size255UShort(table_index); // 255UInt16 index entry
|
|
}
|
|
}
|
|
}
|
|
|
|
// compressed data
|
|
size += compressed_data_length;
|
|
size = Round4(size);
|
|
|
|
size += extended_metadata_length;
|
|
return size;
|
|
}
|
|
|
|
size_t ComputeUncompressedLength(const Font& font) {
|
|
// sfnt header + offset table
|
|
size_t size = 12 + 16 * font.num_tables;
|
|
for (const auto& entry : font.tables) {
|
|
const Font::Table& table = entry.second;
|
|
if (table.tag & 0x80808080) continue; // xform tables don't stay
|
|
if (table.IsReused()) continue; // don't have to pay twice
|
|
size += Round4(table.length);
|
|
}
|
|
return size;
|
|
}
|
|
|
|
size_t ComputeUncompressedLength(const FontCollection& font_collection) {
|
|
if (font_collection.flavor != kTtcFontFlavor) {
|
|
return ComputeUncompressedLength(font_collection.fonts[0]);
|
|
}
|
|
size_t size = CollectionHeaderSize(font_collection.header_version,
|
|
font_collection.fonts.size());
|
|
for (const auto& font : font_collection.fonts) {
|
|
size += ComputeUncompressedLength(font);
|
|
}
|
|
return size;
|
|
}
|
|
|
|
size_t ComputeTotalTransformLength(const Font& font) {
|
|
size_t total = 0;
|
|
for (const auto& i : font.tables) {
|
|
const Font::Table& table = i.second;
|
|
if (table.IsReused()) {
|
|
continue;
|
|
}
|
|
if (table.tag & 0x80808080 || !font.FindTable(table.tag ^ 0x80808080)) {
|
|
// Count transformed tables and non-transformed tables that do not have
|
|
// transformed versions.
|
|
total += table.length;
|
|
}
|
|
}
|
|
return total;
|
|
}
|
|
|
|
} // namespace
|
|
|
|
size_t MaxWOFF2CompressedSize(const uint8_t* data, size_t length) {
|
|
return MaxWOFF2CompressedSize(data, length, "");
|
|
}
|
|
|
|
size_t MaxWOFF2CompressedSize(const uint8_t* data, size_t length,
|
|
const string& extended_metadata) {
|
|
// Except for the header size, which is 32 bytes larger in woff2 format,
|
|
// all other parts should be smaller (table header in short format,
|
|
// transformations and compression). Just to be sure, we will give some
|
|
// headroom anyway.
|
|
return length + 1024 + extended_metadata.length();
|
|
}
|
|
|
|
uint32_t CompressedBufferSize(uint32_t original_size) {
|
|
return 1.2 * original_size + 10240;
|
|
}
|
|
|
|
bool TransformFontCollection(FontCollection* font_collection) {
|
|
for (auto& font : font_collection->fonts) {
|
|
if (!TransformGlyfAndLocaTables(&font)) {
|
|
#ifdef FONT_COMPRESSION_BIN
|
|
fprintf(stderr, "glyf/loca transformation failed.\n");
|
|
#endif
|
|
return FONT_COMPRESSION_FAILURE();
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool ConvertTTFToWOFF2(const uint8_t *data, size_t length,
|
|
uint8_t *result, size_t *result_length) {
|
|
WOFF2Params params;
|
|
return ConvertTTFToWOFF2(data, length, result, result_length,
|
|
params);
|
|
}
|
|
|
|
bool ConvertTTFToWOFF2(const uint8_t *data, size_t length,
|
|
uint8_t *result, size_t *result_length,
|
|
const WOFF2Params& params) {
|
|
FontCollection font_collection;
|
|
if (!ReadFontCollection(data, length, &font_collection)) {
|
|
#ifdef FONT_COMPRESSION_BIN
|
|
fprintf(stderr, "Parsing of the input font failed.\n");
|
|
#endif
|
|
return FONT_COMPRESSION_FAILURE();
|
|
}
|
|
|
|
if (!NormalizeFontCollection(&font_collection)) {
|
|
return FONT_COMPRESSION_FAILURE();
|
|
}
|
|
|
|
if (params.allow_transforms && !TransformFontCollection(&font_collection)) {
|
|
return FONT_COMPRESSION_FAILURE();
|
|
} else {
|
|
// glyf/loca use 11 to flag "not transformed"
|
|
for (auto& font : font_collection.fonts) {
|
|
Font::Table* glyf_table = font.FindTable(kGlyfTableTag);
|
|
Font::Table* loca_table = font.FindTable(kLocaTableTag);
|
|
if (glyf_table) {
|
|
glyf_table->flag_byte |= 0xc0;
|
|
}
|
|
if (loca_table) {
|
|
loca_table->flag_byte |= 0xc0;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Although the compressed size of each table in the final woff2 file won't
|
|
// be larger than its transform_length, we have to allocate a large enough
|
|
// buffer for the compressor, since the compressor can potentially increase
|
|
// the size. If the compressor overflows this, it should return false and
|
|
// then this function will also return false.
|
|
|
|
size_t total_transform_length = 0;
|
|
for (const auto& font : font_collection.fonts) {
|
|
total_transform_length += ComputeTotalTransformLength(font);
|
|
}
|
|
size_t compression_buffer_size = CompressedBufferSize(total_transform_length);
|
|
std::vector<uint8_t> compression_buf(compression_buffer_size);
|
|
uint32_t total_compressed_length = compression_buffer_size;
|
|
|
|
// Collect all transformed data into one place in output order.
|
|
std::vector<uint8_t> transform_buf(total_transform_length);
|
|
size_t transform_offset = 0;
|
|
for (const auto& font : font_collection.fonts) {
|
|
for (const auto tag : font.OutputOrderedTags()) {
|
|
const Font::Table& original = font.tables.at(tag);
|
|
if (original.IsReused()) continue;
|
|
if (tag & 0x80808080) continue;
|
|
const Font::Table* table_to_store = font.FindTable(tag ^ 0x80808080);
|
|
if (table_to_store == NULL) table_to_store = &original;
|
|
|
|
StoreBytes(table_to_store->data, table_to_store->length,
|
|
&transform_offset, &transform_buf[0]);
|
|
}
|
|
}
|
|
|
|
// Compress all transformed data in one stream.
|
|
if (!Woff2Compress(transform_buf.data(), total_transform_length,
|
|
&compression_buf[0],
|
|
&total_compressed_length,
|
|
params.brotli_quality)) {
|
|
#ifdef FONT_COMPRESSION_BIN
|
|
fprintf(stderr, "Compression of combined table failed.\n");
|
|
#endif
|
|
return FONT_COMPRESSION_FAILURE();
|
|
}
|
|
|
|
#ifdef FONT_COMPRESSION_BIN
|
|
fprintf(stderr, "Compressed %zu to %u.\n", total_transform_length,
|
|
total_compressed_length);
|
|
#endif
|
|
|
|
// Compress the extended metadata
|
|
// TODO(user): how does this apply to collections
|
|
uint32_t compressed_metadata_buf_length =
|
|
CompressedBufferSize(params.extended_metadata.length());
|
|
std::vector<uint8_t> compressed_metadata_buf(compressed_metadata_buf_length);
|
|
|
|
if (params.extended_metadata.length() > 0) {
|
|
if (!TextCompress((const uint8_t*)params.extended_metadata.data(),
|
|
params.extended_metadata.length(),
|
|
compressed_metadata_buf.data(),
|
|
&compressed_metadata_buf_length,
|
|
params.brotli_quality)) {
|
|
#ifdef FONT_COMPRESSION_BIN
|
|
fprintf(stderr, "Compression of extended metadata failed.\n");
|
|
#endif
|
|
return FONT_COMPRESSION_FAILURE();
|
|
}
|
|
} else {
|
|
compressed_metadata_buf_length = 0;
|
|
}
|
|
|
|
std::vector<Table> tables;
|
|
std::map<std::pair<uint32_t, uint32_t>, uint16_t> index_by_tag_offset;
|
|
|
|
for (const auto& font : font_collection.fonts) {
|
|
|
|
for (const auto tag : font.OutputOrderedTags()) {
|
|
const Font::Table& src_table = font.tables.at(tag);
|
|
if (src_table.IsReused()) {
|
|
continue;
|
|
}
|
|
|
|
std::pair<uint32_t, uint32_t> tag_offset(src_table.tag, src_table.offset);
|
|
if (index_by_tag_offset.find(tag_offset) == index_by_tag_offset.end()) {
|
|
index_by_tag_offset[tag_offset] = tables.size();
|
|
} else {
|
|
return false;
|
|
}
|
|
|
|
Table table;
|
|
table.tag = src_table.tag;
|
|
table.flags = src_table.flag_byte;
|
|
table.src_length = src_table.length;
|
|
table.transform_length = src_table.length;
|
|
const uint8_t* transformed_data = src_table.data;
|
|
const Font::Table* transformed_table =
|
|
font.FindTable(src_table.tag ^ 0x80808080);
|
|
if (transformed_table != NULL) {
|
|
table.flags = transformed_table->flag_byte;
|
|
table.flags |= kWoff2FlagsTransform;
|
|
table.transform_length = transformed_table->length;
|
|
transformed_data = transformed_table->data;
|
|
|
|
}
|
|
tables.push_back(table);
|
|
}
|
|
}
|
|
|
|
size_t woff2_length = ComputeWoff2Length(font_collection, tables,
|
|
index_by_tag_offset, total_compressed_length,
|
|
compressed_metadata_buf_length);
|
|
if (woff2_length > *result_length) {
|
|
#ifdef FONT_COMPRESSION_BIN
|
|
fprintf(stderr, "Result allocation was too small (%zd vs %zd bytes).\n",
|
|
*result_length, woff2_length);
|
|
#endif
|
|
return FONT_COMPRESSION_FAILURE();
|
|
}
|
|
*result_length = woff2_length;
|
|
|
|
size_t offset = 0;
|
|
|
|
// start of woff2 header (http://www.w3.org/TR/WOFF2/#woff20Header)
|
|
StoreU32(kWoff2Signature, &offset, result);
|
|
if (font_collection.flavor != kTtcFontFlavor) {
|
|
StoreU32(font_collection.fonts[0].flavor, &offset, result);
|
|
} else {
|
|
StoreU32(kTtcFontFlavor, &offset, result);
|
|
}
|
|
StoreU32(woff2_length, &offset, result);
|
|
Store16(tables.size(), &offset, result);
|
|
Store16(0, &offset, result); // reserved
|
|
// totalSfntSize
|
|
StoreU32(ComputeUncompressedLength(font_collection), &offset, result);
|
|
StoreU32(total_compressed_length, &offset, result); // totalCompressedSize
|
|
|
|
// Let's just all be v1.0
|
|
Store16(1, &offset, result); // majorVersion
|
|
Store16(0, &offset, result); // minorVersion
|
|
if (compressed_metadata_buf_length > 0) {
|
|
StoreU32(woff2_length - compressed_metadata_buf_length,
|
|
&offset, result); // metaOffset
|
|
StoreU32(compressed_metadata_buf_length, &offset, result); // metaLength
|
|
StoreU32(params.extended_metadata.length(),
|
|
&offset, result); // metaOrigLength
|
|
} else {
|
|
StoreU32(0, &offset, result); // metaOffset
|
|
StoreU32(0, &offset, result); // metaLength
|
|
StoreU32(0, &offset, result); // metaOrigLength
|
|
}
|
|
StoreU32(0, &offset, result); // privOffset
|
|
StoreU32(0, &offset, result); // privLength
|
|
// end of woff2 header
|
|
|
|
// table directory (http://www.w3.org/TR/WOFF2/#table_dir_format)
|
|
for (const auto& table : tables) {
|
|
StoreTableEntry(table, &offset, result);
|
|
}
|
|
|
|
// for collections only, collection table directory
|
|
if (font_collection.flavor == kTtcFontFlavor) {
|
|
StoreU32(font_collection.header_version, &offset, result);
|
|
Store255UShort(font_collection.fonts.size(), &offset, result);
|
|
for (const Font& font : font_collection.fonts) {
|
|
|
|
uint16_t num_tables = 0;
|
|
for (const auto& entry : font.tables) {
|
|
const Font::Table& table = entry.second;
|
|
if (table.tag & 0x80808080) continue; // don't write xform tables
|
|
num_tables++;
|
|
}
|
|
Store255UShort(num_tables, &offset, result);
|
|
|
|
StoreU32(font.flavor, &offset, result);
|
|
for (const auto& entry : font.tables) {
|
|
const Font::Table& table = entry.second;
|
|
if (table.tag & 0x80808080) continue; // don't write xform tables
|
|
|
|
// for reused tables, only the original has an updated offset
|
|
uint32_t table_offset =
|
|
table.IsReused() ? table.reuse_of->offset : table.offset;
|
|
uint32_t table_length =
|
|
table.IsReused() ? table.reuse_of->length : table.length;
|
|
std::pair<uint32_t, uint32_t> tag_offset(table.tag, table_offset);
|
|
if (index_by_tag_offset.find(tag_offset) == index_by_tag_offset.end()) {
|
|
#ifdef FONT_COMPRESSION_BIN
|
|
fprintf(stderr, "Missing table index for offset 0x%08x\n",
|
|
table_offset);
|
|
#endif
|
|
return FONT_COMPRESSION_FAILURE();
|
|
}
|
|
uint16_t index = index_by_tag_offset[tag_offset];
|
|
Store255UShort(index, &offset, result);
|
|
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
// compressed data format (http://www.w3.org/TR/WOFF2/#table_format)
|
|
|
|
StoreBytes(&compression_buf[0], total_compressed_length, &offset, result);
|
|
offset = Round4(offset);
|
|
|
|
StoreBytes(compressed_metadata_buf.data(), compressed_metadata_buf_length,
|
|
&offset, result);
|
|
|
|
if (*result_length != offset) {
|
|
#ifdef FONT_COMPRESSION_BIN
|
|
fprintf(stderr, "Mismatch between computed and actual length "
|
|
"(%zd vs %zd)\n", *result_length, offset);
|
|
#endif
|
|
return FONT_COMPRESSION_FAILURE();
|
|
}
|
|
return true;
|
|
}
|
|
|
|
} // namespace woff2
|