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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 "feat.h"
#include "name.h"
namespace ots {
bool OpenTypeFEAT::Parse(const uint8_t* data, size_t length) {
if (GetFont()->dropped_graphite) {
return Drop("Skipping Graphite table");
}
Buffer table(data, length);
if (!table.ReadU32(&this->version)) {
return DropGraphite("Failed to read version");
}
if (this->version >> 16 != 1 && this->version >> 16 != 2) {
return DropGraphite("Unsupported table version: %u", this->version >> 16);
}
if (!table.ReadU16(&this->numFeat)) {
return DropGraphite("Failed to read numFeat");
}
if (!table.ReadU16(&this->reserved)) {
return DropGraphite("Failed to read reserved");
}
if (this->reserved != 0) {
Warning("Nonzero reserved");
}
if (!table.ReadU32(&this->reserved2)) {
return DropGraphite("Failed to read valid reserved2");
}
if (this->reserved2 != 0) {
Warning("Nonzero reserved2");
}
std::unordered_set<size_t> unverified;
//this->features.resize(this->numFeat, this);
for (unsigned i = 0; i < this->numFeat; ++i) {
this->features.emplace_back(this);
FeatureDefn& feature = this->features[i];
if (!feature.ParsePart(table)) {
return DropGraphite("Failed to read features[%u]", i);
}
this->feature_ids.insert(feature.id);
for (unsigned j = 0; j < feature.numSettings; ++j) {
size_t offset = feature.offset + j * 4;
if (offset < feature.offset || offset > length) {
return DropGraphite("Invalid FeatSettingDefn offset %zu/%zu",
offset, length);
}
unverified.insert(offset);
// need to verify that this FeatureDefn points to valid
// FeatureSettingDefn
}
}
while (table.remaining()) {
bool used = unverified.erase(table.offset());
FeatureSettingDefn featSetting(this);
if (!featSetting.ParsePart(table, used)) {
return DropGraphite("Failed to read a FeatureSettingDefn");
}
featSettings.push_back(featSetting);
}
if (!unverified.empty()) {
return DropGraphite("%zu incorrect offsets into featSettings",
unverified.size());
}
if (table.remaining()) {
return Warning("%zu bytes unparsed", table.remaining());
}
return true;
}
bool OpenTypeFEAT::Serialize(OTSStream* out) {
if (!out->WriteU32(this->version) ||
!out->WriteU16(this->numFeat) ||
!out->WriteU16(this->reserved) ||
!out->WriteU32(this->reserved2) ||
!SerializeParts(this->features, out) ||
!SerializeParts(this->featSettings, out)) {
return Error("Failed to write table");
}
return true;
}
bool OpenTypeFEAT::IsValidFeatureId(uint32_t id) const {
return feature_ids.count(id);
}
bool OpenTypeFEAT::FeatureDefn::ParsePart(Buffer& table) {
OpenTypeNAME* name = static_cast<OpenTypeNAME*>(
parent->GetFont()->GetTypedTable(OTS_TAG_NAME));
if (!name) {
return parent->Error("FeatureDefn: Required name table is missing");
}
if (parent->version >> 16 >= 2 && !table.ReadU32(&this->id)) {
return parent->Error("FeatureDefn: Failed to read id");
}
if (parent->version >> 16 == 1) {
uint16_t id;
if (!table.ReadU16(&id)) {
return parent->Error("FeatureDefn: Failed to read id");
}
this->id = id;
}
if (!table.ReadU16(&this->numSettings)) {
return parent->Error("FeatureDefn: Failed to read numSettings");
}
if (parent->version >> 16 >= 2) {
if (!table.ReadU16(&this->reserved)) {
return parent->Error("FeatureDefn: Failed to read reserved");
}
if (this->reserved != 0) {
parent->Warning("FeatureDefn: Nonzero reserved");
}
}
if (!table.ReadU32(&this->offset)) {
return parent->Error("FeatureDefn: Failed to read offset");
} // validity of offset verified in OpenTypeFEAT::Parse
if (!table.ReadU16(&this->flags)) {
return parent->Error("FeatureDefn: Failed to read flags");
}
if ((this->flags & RESERVED) != 0) {
this->flags &= ~RESERVED;
parent->Warning("FeatureDefn: Nonzero (flags & 0x%x) repaired", RESERVED);
}
if (this->flags & HAS_DEFAULT_SETTING &&
(this->flags & DEFAULT_SETTING) >= this->numSettings) {
return parent->Error("FeatureDefn: (flags & 0x%x) is set but (flags & 0x%x "
"is not a valid setting index", HAS_DEFAULT_SETTING,
DEFAULT_SETTING);
}
if (!table.ReadU16(&this->label)) {
return parent->Error("FeatureDefn: Failed to read label");
}
if (!name->IsValidNameId(this->label)) {
if (this->id == 1 && name->IsValidNameId(this->label, true)) {
parent->Warning("FeatureDefn: Missing NameRecord repaired for feature"
" with id=%u, label=%u", this->id, this->label);
}
else {
return parent->Error("FeatureDefn: Invalid label");
}
}
return true;
}
bool OpenTypeFEAT::FeatureDefn::SerializePart(OTSStream* out) const {
if ((parent->version >> 16 >= 2 && !out->WriteU32(this->id)) ||
(parent->version >> 16 == 1 &&
!out->WriteU16(static_cast<uint16_t>(this->id))) ||
!out->WriteU16(this->numSettings) ||
(parent->version >> 16 >= 2 && !out->WriteU16(this->reserved)) ||
!out->WriteU32(this->offset) ||
!out->WriteU16(this->flags) ||
!out->WriteU16(this->label)) {
return parent->Error("FeatureDefn: Failed to write");
}
return true;
}
bool OpenTypeFEAT::FeatureSettingDefn::ParsePart(Buffer& table, bool used) {
OpenTypeNAME* name = static_cast<OpenTypeNAME*>(
parent->GetFont()->GetTypedTable(OTS_TAG_NAME));
if (!name) {
return parent->Error("FeatureSettingDefn: Required name table is missing");
}
if (!table.ReadS16(&this->value)) {
return parent->Error("FeatureSettingDefn: Failed to read value");
}
if (!table.ReadU16(&this->label) ||
(used && !name->IsValidNameId(this->label))) {
return parent->Error("FeatureSettingDefn: Failed to read valid label");
}
return true;
}
bool OpenTypeFEAT::FeatureSettingDefn::SerializePart(OTSStream* out) const {
if (!out->WriteS16(this->value) ||
!out->WriteU16(this->label)) {
return parent->Error("FeatureSettingDefn: Failed to write");
}
return true;
}
} // namespace ots
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