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// Copyright (c) 2009-2017 The OTS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "glat.h"
#include "gloc.h"
#include "mozilla/Compression.h"
#include <list>
#include <memory>
namespace ots {
// -----------------------------------------------------------------------------
// OpenTypeGLAT_v1
// -----------------------------------------------------------------------------
bool OpenTypeGLAT_v1::Parse(const uint8_t* data, size_t length) {
Buffer table(data, length);
OpenTypeGLOC* gloc = static_cast<OpenTypeGLOC*>(
GetFont()->GetTypedTable(OTS_TAG_GLOC));
if (!gloc) {
return DropGraphite("Required Gloc table is missing");
}
if (!table.ReadU32(&this->version) || this->version >> 16 != 1) {
return DropGraphite("Failed to read version");
}
const std::vector<uint32_t>& locations = gloc->GetLocations();
if (locations.empty()) {
return DropGraphite("No locations from Gloc table");
}
std::list<uint32_t> unverified(locations.begin(), locations.end());
while (table.remaining()) {
GlatEntry entry(this);
if (table.offset() > unverified.front()) {
return DropGraphite("Offset check failed for a GlatEntry");
}
if (table.offset() == unverified.front()) {
unverified.pop_front();
}
if (unverified.empty()) {
return DropGraphite("Expected more locations");
}
if (!entry.ParsePart(table)) {
return DropGraphite("Failed to read a GlatEntry");
}
this->entries.push_back(entry);
}
if (unverified.size() != 1 || unverified.front() != table.offset()) {
return DropGraphite("%zu location(s) could not be verified", unverified.size());
}
if (table.remaining()) {
return Warning("%zu bytes unparsed", table.remaining());
}
return true;
}
bool OpenTypeGLAT_v1::Serialize(OTSStream* out) {
assert(ShouldSerialize());
if (!out->WriteU32(this->version) ||
!SerializeParts(this->entries, out)) {
return Error("Failed to write table");
}
return true;
}
bool OpenTypeGLAT_v1::GlatEntry::ParsePart(Buffer& table) {
if (!table.ReadU8(&this->attNum)) {
return parent->Error("GlatEntry: Failed to read attNum");
}
if (!table.ReadU8(&this->num)) {
return parent->Error("GlatEntry: Failed to read num");
}
//this->attributes.resize(this->num);
for (int i = 0; i < this->num; ++i) {
this->attributes.emplace_back();
if (!table.ReadS16(&this->attributes[i])) {
return parent->Error("GlatEntry: Failed to read attribute %u", i);
}
}
return true;
}
bool OpenTypeGLAT_v1::GlatEntry::SerializePart(OTSStream* out) const {
if (!out->WriteU8(this->attNum) ||
!out->WriteU8(this->num) ||
!SerializeParts(this->attributes, out)) {
return parent->Error("GlatEntry: Failed to write");
}
return true;
}
// -----------------------------------------------------------------------------
// OpenTypeGLAT_v2
// -----------------------------------------------------------------------------
bool OpenTypeGLAT_v2::Parse(const uint8_t* data, size_t length) {
Buffer table(data, length);
OpenTypeGLOC* gloc = static_cast<OpenTypeGLOC*>(
GetFont()->GetTypedTable(OTS_TAG_GLOC));
if (!gloc) {
return DropGraphite("Required Gloc table is missing");
}
if (!table.ReadU32(&this->version) || this->version >> 16 != 1) {
return DropGraphite("Failed to read version");
}
const std::vector<uint32_t>& locations = gloc->GetLocations();
if (locations.empty()) {
return DropGraphite("No locations from Gloc table");
}
std::list<uint32_t> unverified(locations.begin(), locations.end());
while (table.remaining()) {
GlatEntry entry(this);
if (table.offset() > unverified.front()) {
return DropGraphite("Offset check failed for a GlatEntry");
}
if (table.offset() == unverified.front()) {
unverified.pop_front();
}
if (unverified.empty()) {
return DropGraphite("Expected more locations");
}
if (!entry.ParsePart(table)) {
return DropGraphite("Failed to read a GlatEntry");
}
this->entries.push_back(entry);
}
if (unverified.size() != 1 || unverified.front() != table.offset()) {
return DropGraphite("%zu location(s) could not be verified", unverified.size());
}
if (table.remaining()) {
return Warning("%zu bytes unparsed", table.remaining());
}
return true;
}
bool OpenTypeGLAT_v2::Serialize(OTSStream* out) {
assert(ShouldSerialize());
if (!out->WriteU32(this->version) ||
!SerializeParts(this->entries, out)) {
return Error("Failed to write table");
}
return true;
}
bool OpenTypeGLAT_v2::GlatEntry::ParsePart(Buffer& table) {
if (!table.ReadS16(&this->attNum)) {
return parent->Error("GlatEntry: Failed to read attNum");
}
if (!table.ReadS16(&this->num) || this->num < 0) {
return parent->Error("GlatEntry: Failed to read valid num");
}
//this->attributes.resize(this->num);
for (int i = 0; i < this->num; ++i) {
this->attributes.emplace_back();
if (!table.ReadS16(&this->attributes[i])) {
return parent->Error("GlatEntry: Failed to read attribute %u", i);
}
}
return true;
}
bool OpenTypeGLAT_v2::GlatEntry::SerializePart(OTSStream* out) const {
if (!out->WriteS16(this->attNum) ||
!out->WriteS16(this->num) ||
!SerializeParts(this->attributes, out)) {
return parent->Error("GlatEntry: Failed to write");
}
return true;
}
// -----------------------------------------------------------------------------
// OpenTypeGLAT_v3
// -----------------------------------------------------------------------------
bool OpenTypeGLAT_v3::Parse(const uint8_t* data, size_t length,
bool prevent_decompression) {
Buffer table(data, length);
OpenTypeGLOC* gloc = static_cast<OpenTypeGLOC*>(
GetFont()->GetTypedTable(OTS_TAG_GLOC));
if (!gloc) {
return DropGraphite("Required Gloc table is missing");
}
if (!table.ReadU32(&this->version) || this->version >> 16 != 3) {
return DropGraphite("Failed to read version");
}
if (!table.ReadU32(&this->compHead)) {
return DropGraphite("Failed to read compression header");
}
switch ((this->compHead & SCHEME) >> 27) {
case 0: // uncompressed
break;
case 1: { // lz4
if (prevent_decompression) {
return DropGraphite("Illegal nested compression");
}
size_t decompressed_size = this->compHead & FULL_SIZE;
if (decompressed_size < length) {
return DropGraphite("Decompressed size is less than compressed size");
}
if (decompressed_size == 0) {
return DropGraphite("Decompressed size is set to 0");
}
// decompressed table must be <= OTS_MAX_DECOMPRESSED_TABLE_SIZE
if (decompressed_size > OTS_MAX_DECOMPRESSED_TABLE_SIZE) {
return DropGraphite("Decompressed size exceeds %gMB: %gMB",
OTS_MAX_DECOMPRESSED_TABLE_SIZE / (1024.0 * 1024.0),
decompressed_size / (1024.0 * 1024.0));
}
std::unique_ptr<uint8_t> decompressed(new uint8_t[decompressed_size]());
size_t outputSize = 0;
bool ret = mozilla::Compression::LZ4::decompressPartial(
reinterpret_cast<const char*>(data + table.offset()),
table.remaining(), // input buffer size (input size + padding)
reinterpret_cast<char*>(decompressed.get()),
decompressed_size, // target output size
&outputSize); // return output size
if (!ret || outputSize != decompressed_size) {
return DropGraphite("Decompression failed");
}
return this->Parse(decompressed.get(), decompressed_size, true);
}
default:
return DropGraphite("Unknown compression scheme");
}
if (this->compHead & RESERVED) {
Warning("Nonzero reserved");
}
const std::vector<uint32_t>& locations = gloc->GetLocations();
if (locations.empty()) {
return DropGraphite("No locations from Gloc table");
}
std::list<uint32_t> unverified(locations.begin(), locations.end());
//this->entries.resize(locations.size() - 1, this);
for (size_t i = 0; i < locations.size() - 1; ++i) {
this->entries.emplace_back(this);
if (table.offset() != unverified.front()) {
return DropGraphite("Offset check failed for a GlyphAttrs");
}
unverified.pop_front();
if (!this->entries[i].ParsePart(table,
unverified.front() - table.offset())) {
// unverified.front() is guaranteed to exist because of the number of
// iterations of this loop
return DropGraphite("Failed to read a GlyphAttrs");
}
}
if (unverified.size() != 1 || unverified.front() != table.offset()) {
return DropGraphite("%zu location(s) could not be verified", unverified.size());
}
if (table.remaining()) {
return Warning("%zu bytes unparsed", table.remaining());
}
return true;
}
bool OpenTypeGLAT_v3::Serialize(OTSStream* out) {
assert(ShouldSerialize());
if (!out->WriteU32(this->version) ||
!out->WriteU32(this->compHead) ||
!SerializeParts(this->entries, out)) {
return Error("Failed to write table");
}
return true;
}
bool OpenTypeGLAT_v3::GlyphAttrs::ParsePart(Buffer& table, const size_t size) {
size_t init_offset = table.offset();
if (parent->compHead & OCTABOXES && !octabox.ParsePart(table)) {
// parent->flags & 0b1: octaboxes are present flag
return parent->Error("GlyphAttrs: Failed to read octabox");
}
while (table.offset() < init_offset + size) {
GlatEntry entry(parent);
if (!entry.ParsePart(table)) {
return parent->Error("GlyphAttrs: Failed to read a GlatEntry");
}
this->entries.push_back(entry);
}
return true;
}
bool OpenTypeGLAT_v3::GlyphAttrs::SerializePart(OTSStream* out) const {
if ((parent->compHead & OCTABOXES && !octabox.SerializePart(out)) ||
!SerializeParts(this->entries, out)) {
return parent->Error("GlyphAttrs: Failed to write");
}
return true;
}
bool OpenTypeGLAT_v3::GlyphAttrs::
OctaboxMetrics::ParsePart(Buffer& table) {
if (!table.ReadU16(&this->subbox_bitmap)) {
return parent->Error("OctaboxMetrics: Failed to read subbox_bitmap");
}
if (!table.ReadU8(&this->diag_neg_min)) {
return parent->Error("OctaboxMetrics: Failed to read diag_neg_min");
}
if (!table.ReadU8(&this->diag_neg_max) ||
this->diag_neg_max < this->diag_neg_min) {
return parent->Error("OctaboxMetrics: Failed to read valid diag_neg_max");
}
if (!table.ReadU8(&this->diag_pos_min)) {
return parent->Error("OctaboxMetrics: Failed to read diag_pos_min");
}
if (!table.ReadU8(&this->diag_pos_max) ||
this->diag_pos_max < this->diag_pos_min) {
return parent->Error("OctaboxMetrics: Failed to read valid diag_pos_max");
}
unsigned subboxes_len = 0; // count of 1's in this->subbox_bitmap
for (uint16_t i = this->subbox_bitmap; i; i >>= 1) {
if (i & 0b1) {
++subboxes_len;
}
}
//this->subboxes.resize(subboxes_len, parent);
for (unsigned i = 0; i < subboxes_len; i++) {
this->subboxes.emplace_back(parent);
if (!this->subboxes[i].ParsePart(table)) {
return parent->Error("OctaboxMetrics: Failed to read subbox[%u]", i);
}
}
return true;
}
bool OpenTypeGLAT_v3::GlyphAttrs::
OctaboxMetrics::SerializePart(OTSStream* out) const {
if (!out->WriteU16(this->subbox_bitmap) ||
!out->WriteU8(this->diag_neg_min) ||
!out->WriteU8(this->diag_neg_max) ||
!out->WriteU8(this->diag_pos_min) ||
!out->WriteU8(this->diag_pos_max) ||
!SerializeParts(this->subboxes, out)) {
return parent->Error("OctaboxMetrics: Failed to write");
}
return true;
}
bool OpenTypeGLAT_v3::GlyphAttrs::OctaboxMetrics::
SubboxEntry::ParsePart(Buffer& table) {
if (!table.ReadU8(&this->left)) {
return parent->Error("SubboxEntry: Failed to read left");
}
if (!table.ReadU8(&this->right) || this->right < this->left) {
return parent->Error("SubboxEntry: Failed to read valid right");
}
if (!table.ReadU8(&this->bottom)) {
return parent->Error("SubboxEntry: Failed to read bottom");
}
if (!table.ReadU8(&this->top) || this->top < this->bottom) {
return parent->Error("SubboxEntry: Failed to read valid top");
}
if (!table.ReadU8(&this->diag_pos_min)) {
return parent->Error("SubboxEntry: Failed to read diag_pos_min");
}
if (!table.ReadU8(&this->diag_pos_max) ||
this->diag_pos_max < this->diag_pos_min) {
return parent->Error("SubboxEntry: Failed to read valid diag_pos_max");
}
if (!table.ReadU8(&this->diag_neg_min)) {
return parent->Error("SubboxEntry: Failed to read diag_neg_min");
}
if (!table.ReadU8(&this->diag_neg_max) ||
this->diag_neg_max < this->diag_neg_min) {
return parent->Error("SubboxEntry: Failed to read valid diag_neg_max");
}
return true;
}
bool OpenTypeGLAT_v3::GlyphAttrs::OctaboxMetrics::
SubboxEntry::SerializePart(OTSStream* out) const {
if (!out->WriteU8(this->left) ||
!out->WriteU8(this->right) ||
!out->WriteU8(this->bottom) ||
!out->WriteU8(this->top) ||
!out->WriteU8(this->diag_pos_min) ||
!out->WriteU8(this->diag_pos_max) ||
!out->WriteU8(this->diag_neg_min) ||
!out->WriteU8(this->diag_neg_max)) {
return parent->Error("SubboxEntry: Failed to write");
}
return true;
}
bool OpenTypeGLAT_v3::GlyphAttrs::
GlatEntry::ParsePart(Buffer& table) {
if (!table.ReadS16(&this->attNum)) {
return parent->Error("GlatEntry: Failed to read attNum");
}
if (!table.ReadS16(&this->num) || this->num < 0) {
return parent->Error("GlatEntry: Failed to read valid num");
}
//this->attributes.resize(this->num);
for (int i = 0; i < this->num; ++i) {
this->attributes.emplace_back();
if (!table.ReadS16(&this->attributes[i])) {
return parent->Error("GlatEntry: Failed to read attribute %u", i);
}
}
return true;
}
bool OpenTypeGLAT_v3::GlyphAttrs::
GlatEntry::SerializePart(OTSStream* out) const {
if (!out->WriteS16(this->attNum) ||
!out->WriteS16(this->num) ||
!SerializeParts(this->attributes, out)) {
return parent->Error("GlatEntry: Failed to write");
}
return true;
}
// -----------------------------------------------------------------------------
// OpenTypeGLAT
// -----------------------------------------------------------------------------
bool OpenTypeGLAT::Parse(const uint8_t* data, size_t length) {
Buffer table(data, length);
uint32_t version;
if (!table.ReadU32(&version)) {
return DropGraphite("Failed to read version");
}
switch (version >> 16) {
case 1:
this->handler = new OpenTypeGLAT_v1(this->font, this->tag);
break;
case 2:
this->handler = new OpenTypeGLAT_v2(this->font, this->tag);
break;
case 3: {
this->handler = new OpenTypeGLAT_v3(this->font, this->tag);
break;
}
default:
return DropGraphite("Unsupported table version: %u", version >> 16);
}
return this->handler->Parse(data, length);
}
bool OpenTypeGLAT::Serialize(OTSStream* out) {
if (!this->handler) {
return Error("No Glat table parsed");
}
return this->handler->Serialize(out);
}
} // namespace ots