1 files changed, 142 insertions, 0 deletions
diff --git a/extern/draco/draco/src/draco/metadata/metadata_decoder.cc b/extern/draco/draco/src/draco/metadata/metadata_decoder.cc
new file mode 100644
index 00000000000..e664e4fa524
--- /dev/null
+++ b/extern/draco/draco/src/draco/metadata/metadata_decoder.cc
@@ -0,0 +1,142 @@
+// Copyright 2017 The Draco Authors.
+//
+// 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.
+//
+#include "draco/metadata/metadata_decoder.h"
+
+#include <string>
+
+#include "draco/core/varint_decoding.h"
+
+namespace draco {
+
+MetadataDecoder::MetadataDecoder() : buffer_(nullptr) {}
+
+bool MetadataDecoder::DecodeMetadata(DecoderBuffer *in_buffer,
+                                     Metadata *metadata) {
+  if (!metadata) {
+    return false;
+  }
+  buffer_ = in_buffer;
+  return DecodeMetadata(metadata);
+}
+
+bool MetadataDecoder::DecodeGeometryMetadata(DecoderBuffer *in_buffer,
+                                             GeometryMetadata *metadata) {
+  if (!metadata) {
+    return false;
+  }
+  buffer_ = in_buffer;
+  uint32_t num_att_metadata = 0;
+  if (!DecodeVarint(&num_att_metadata, buffer_)) {
+    return false;
+  }
+  // Decode attribute metadata.
+  for (uint32_t i = 0; i < num_att_metadata; ++i) {
+    uint32_t att_unique_id;
+    if (!DecodeVarint(&att_unique_id, buffer_)) {
+      return false;
+    }
+    std::unique_ptr<AttributeMetadata> att_metadata =
+        std::unique_ptr<AttributeMetadata>(new AttributeMetadata());
+    att_metadata->set_att_unique_id(att_unique_id);
+    if (!DecodeMetadata(static_cast<Metadata *>(att_metadata.get()))) {
+      return false;
+    }
+    metadata->AddAttributeMetadata(std::move(att_metadata));
+  }
+  return DecodeMetadata(static_cast<Metadata *>(metadata));
+}
+
+bool MetadataDecoder::DecodeMetadata(Metadata *metadata) {
+  struct MetadataPair {
+    Metadata *parent_metadata;
+    Metadata *decoded_metadata;
+  };
+  std::vector<MetadataPair> metadata_stack;
+  metadata_stack.push_back({nullptr, metadata});
+  while (!metadata_stack.empty()) {
+    const MetadataPair mp = metadata_stack.back();
+    metadata_stack.pop_back();
+    metadata = mp.decoded_metadata;
+
+    if (mp.parent_metadata != nullptr) {
+      std::string sub_metadata_name;
+      if (!DecodeName(&sub_metadata_name)) {
+        return false;
+      }
+      std::unique_ptr<Metadata> sub_metadata =
+          std::unique_ptr<Metadata>(new Metadata());
+      metadata = sub_metadata.get();
+      mp.parent_metadata->AddSubMetadata(sub_metadata_name,
+                                         std::move(sub_metadata));
+    }
+    if (metadata == nullptr) {
+      return false;
+    }
+
+    uint32_t num_entries = 0;
+    if (!DecodeVarint(&num_entries, buffer_)) {
+      return false;
+    }
+    for (uint32_t i = 0; i < num_entries; ++i) {
+      if (!DecodeEntry(metadata)) {
+        return false;
+      }
+    }
+    uint32_t num_sub_metadata = 0;
+    if (!DecodeVarint(&num_sub_metadata, buffer_)) {
+      return false;
+    }
+    for (uint32_t i = 0; i < num_sub_metadata; ++i) {
+      metadata_stack.push_back({metadata, nullptr});
+    }
+  }
+  return true;
+}
+
+bool MetadataDecoder::DecodeEntry(Metadata *metadata) {
+  std::string entry_name;
+  if (!DecodeName(&entry_name)) {
+    return false;
+  }
+  uint32_t data_size = 0;
+  if (!DecodeVarint(&data_size, buffer_)) {
+    return false;
+  }
+  if (data_size == 0) {
+    return false;
+  }
+  std::vector<uint8_t> entry_value(data_size);
+  if (!buffer_->Decode(&entry_value[0], data_size)) {
+    return false;
+  }
+  metadata->AddEntryBinary(entry_name, entry_value);
+  return true;
+}
+
+bool MetadataDecoder::DecodeName(std::string *name) {
+  uint8_t name_len = 0;
+  if (!buffer_->Decode(&name_len)) {
+    return false;
+  }
+  name->resize(name_len);
+  if (name_len == 0) {
+    return true;
+  }
+  if (!buffer_->Decode(&name->at(0), name_len)) {
+    return false;
+  }
+  return true;
+}
+}  // namespace draco