Protocol Buffer runtime library and 'protoc' plugin

lib/protobuf/runtime/CodedBufferReader.dart

+// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class CodedBufferReader extends CodedReader {
+  PbByteBuffer _input;
+
+  CodedBufferReader.fromBuffer(List<int> _buffer, [
+      int recursionLimit = CodedReader.DEFAULT_RECURSION_LIMIT,
+      int sizeLimit = CodedReader.DEFAULT_SIZE_LIMIT]) :
+      super(recursionLimit, sizeLimit),
+      _input = new PbByteBuffer.fromList(_buffer);
+
+  bool isAtEnd() =>
+      (_currentLimit != -1 && _bufferPos >= _currentLimit) || _input.isEmpty;
+
+  void readGroup(int fieldNumber, Builder builder,
+      ExtensionRegistry extensionRegistry) {
+    if (_recursionDepth >= _recursionLimit) {
+      throw InvalidProtocolBufferException.recursionLimitExceeded();
+    }
+    ++_recursionDepth;
+    builder.mergeFromCodedBufferReader(this);
+    checkLastTagWas(WireFormat.makeTag(fieldNumber,
+        WireFormat.WIRETYPE_END_GROUP));
+    --_recursionDepth;
+  }
+
+  void readUnknownFieldSetGroup(int fieldNumber, UnknownFieldSet_Builder builder) {
+    if (_recursionDepth >= _recursionLimit) {
+      throw InvalidProtocolBufferException.recursionLimitExceeded();
+    }
+    ++_recursionDepth;
+    builder.mergeFromCodedBufferReader(this);
+    checkLastTagWas(WireFormat.makeTag(fieldNumber,
+        WireFormat.WIRETYPE_END_GROUP));
+    --_recursionDepth;
+  }
+
+  void readMessage(Builder builder, ExtensionRegistry extensionRegistry) {
+    int length = readInt32();
+    if (_recursionDepth >= _recursionLimit) {
+      throw InvalidProtocolBufferException.recursionLimitExceeded();
+    }
+    int oldLimit = _pushLimit(length);
+    ++_recursionDepth;
+    builder.mergeFromCodedBufferReader(this);
+    checkLastTagWas(0);
+    --_recursionDepth;
+    _popLimit(oldLimit);
+  }
+
+  int readEnum() => readInt32();
+  int readInt32() => PbCodec.toInt32(readRawVarint());
+  Dynamic readInt64() => PbCodec.toInt64(readRawVarint());
+  int readUint32() => PbCodec.toUint32(readRawVarint());
+  int readUint64() => PbCodec.toUint64(readRawVarint());
+  int readSint32() => PbCodec.toSint32(readRawVarint());
+  Dynamic readSint64() => PbCodec.toSint64(readRawVarint());
+  int readFixed32() => PbCodec.toFixed32(readRaw32());
+  Dynamic readFixed64() => PbCodec.toFixed64(readRaw64());
+  int readSfixed32() => PbCodec.toSfixed32(readRaw32());
+  Dynamic readSfixed64() => PbCodec.toSfixed64(readRaw64());
+  bool readBool() => PbCodec.toBool(readRawVarint());
+  List<int> readBytes() => readRawLengthDelimited();
+  String readString() => decodeUtf8(readRawLengthDelimited());
+  double readFloat() => PbCodec.toFloat(readRaw32());
+  double readDouble() => PbCodec.toDouble(readRaw64());
+
+  int readTag() {
+    if (isAtEnd()) {
+      _lastTag = 0;
+      return 0;
+    }
+
+    _lastTag = readInt32();
+    if (WireFormat.getTagFieldNumber(_lastTag) == 0) {
+      throw InvalidProtocolBufferException.invalidTag();
+    }
+    return _lastTag;
+  }
+
+  List<int> readRawVarint() {
+    List<int> rawBytes = [];
+    rawBytes.add(_readRawByte());
+    while (rawBytes.length < 10 && (rawBytes.last() & 0x80) != 0) {
+      int byte = _readRawByte();
+      if (byte == null) {
+        throw InvalidProtocolBufferException.truncatedMessage();
+      }
+      rawBytes.add(byte);
+    }
+    if ((rawBytes.last() & 0x80) != 0) {
+      throw InvalidProtocolBufferException.malformedVarint();
+    }
+    return rawBytes;
+  }
+
+  List<int> readRaw32() => readRawFixed(4);
+  List<int> readRaw64() => readRawFixed(8);
+  List<int> readRawFixed(int length) => _readRawBytes(length);
+
+  List<int> readRawLengthDelimited() {
+    int length = readInt32();
+    return _readRawBytes(length);
+  }
+
+  int _readRawByte() {
+    _bufferPos++;
+    _checkLimit();
+    int byte = _input.readByte();
+    if (byte == null) {
+      throw InvalidProtocolBufferException.truncatedMessage();
+    }
+    return byte;
+  }
+
+  List<int> _readRawBytes(int size) {
+    _bufferPos += size;
+    _checkLimit();
+    List<int> bytes = _input.readBytes(size);
+    return bytes;
+  }
+
+  void skipField(int tag) {
+    int number = tag >> 3;
+    int wireType = tag & 0x7;
+    switch (wireType) {
+      case WireFormat.WIRETYPE_VARINT:
+        readRawVarint();
+        return;
+      case WireFormat.WIRETYPE_FIXED64:
+        readRaw64();
+        return;
+      case WireFormat.WIRETYPE_LENGTH_DELIMITED:
+        readRawLengthDelimited();
+        return;
+      case WireFormat.WIRETYPE_START_GROUP:
+        UnknownFieldSet_Builder subBuilder = new UnknownFieldSet_Builder();
+        readUnknownFieldSetGroup(number, subBuilder);
+        return;
+      case WireFormat.WIRETYPE_END_GROUP: // should not happen, but ignore?
+        return;
+      case WireFormat.WIRETYPE_FIXED32:
+        readRaw32();
+        return;
+    }
+  }
+
+  void skipRawBytes(int number) {
+    _readRawBytes(number);
+  }
+}