1 files changed, 190 insertions, 0 deletions
diff --git a/gfx/ots/src/feat.cc b/gfx/ots/src/feat.cc
new file mode 100644
index 0000000000..19f22c3bc5
--- /dev/null
+++ b/gfx/ots/src/feat.cc
@@ -0,0 +1,190 @@
+// 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) {
+  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