mirror of
https://github.com/dart-lang/sdk
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42 lines
1.1 KiB
Dart
42 lines
1.1 KiB
Dart
// Copyright (c) 2011, the Dart project authors. Please see the AUTHORS file
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// for details. All rights reserved. Use of this source code is governed by a
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// BSD-style license that can be found in the LICENSE file.
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part of swarmlib;
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// TODO(jimhug): Fill out methods, add encoder, move to shared lib.
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class Decoder {
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int index;
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String data;
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Decoder(this.data) {
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this.index = 0;
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}
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// Reads numbers in variable-length 7-bit encoding. This matches the
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// varint encoding used by protobufs except that it only uses 7
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// bits per byte so it can be efficiently passed as UTF8.
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// For more info, see appengine/encoder.py.
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int readInt() {
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var r = 0;
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for (var i = 0;; i++) {
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var v = data.codeUnitAt(index++);
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r |= (v & 0x3F) << (6 * i);
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if ((v & 0x40) == 0) break;
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}
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return r.toInt();
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}
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bool readBool() {
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final ch = data[index++];
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assert(ch == 'T' || ch == 'F');
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return ch == 'T';
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}
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String readString() {
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int len = readInt();
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String s = data.substring(index, index + len);
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index += len;
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return s;
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}
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}
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