| // Copyright (c) 2015, 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. |
| |
| import 'huffman.dart'; |
| |
| /// The huffman codec for encoding/decoding HTTP/2 header blocks. |
| final HuffmanCodec http2HuffmanCodec = HuffmanCodec(HuffmanEncoder(_codeWords), |
| HuffmanDecoder(generateHuffmanTree(_codeWords))); |
| |
| /// This is the integer representing the End-of-String symbol |
| /// (it is not representable by a byte). |
| const int EOS_BYTE = 256; |
| |
| /// This list of byte encodings via huffman encoding was generated from the |
| /// HPACK specification. |
| const List<EncodedHuffmanValue> _codeWords = <EncodedHuffmanValue>[ |
| EncodedHuffmanValue(0x1ff8, 13), |
| EncodedHuffmanValue(0x7fffd8, 23), |
| EncodedHuffmanValue(0xfffffe2, 28), |
| EncodedHuffmanValue(0xfffffe3, 28), |
| EncodedHuffmanValue(0xfffffe4, 28), |
| EncodedHuffmanValue(0xfffffe5, 28), |
| EncodedHuffmanValue(0xfffffe6, 28), |
| EncodedHuffmanValue(0xfffffe7, 28), |
| EncodedHuffmanValue(0xfffffe8, 28), |
| EncodedHuffmanValue(0xffffea, 24), |
| EncodedHuffmanValue(0x3ffffffc, 30), |
| EncodedHuffmanValue(0xfffffe9, 28), |
| EncodedHuffmanValue(0xfffffea, 28), |
| EncodedHuffmanValue(0x3ffffffd, 30), |
| EncodedHuffmanValue(0xfffffeb, 28), |
| EncodedHuffmanValue(0xfffffec, 28), |
| EncodedHuffmanValue(0xfffffed, 28), |
| EncodedHuffmanValue(0xfffffee, 28), |
| EncodedHuffmanValue(0xfffffef, 28), |
| EncodedHuffmanValue(0xffffff0, 28), |
| EncodedHuffmanValue(0xffffff1, 28), |
| EncodedHuffmanValue(0xffffff2, 28), |
| EncodedHuffmanValue(0x3ffffffe, 30), |
| EncodedHuffmanValue(0xffffff3, 28), |
| EncodedHuffmanValue(0xffffff4, 28), |
| EncodedHuffmanValue(0xffffff5, 28), |
| EncodedHuffmanValue(0xffffff6, 28), |
| EncodedHuffmanValue(0xffffff7, 28), |
| EncodedHuffmanValue(0xffffff8, 28), |
| EncodedHuffmanValue(0xffffff9, 28), |
| EncodedHuffmanValue(0xffffffa, 28), |
| EncodedHuffmanValue(0xffffffb, 28), |
| EncodedHuffmanValue(0x14, 6), |
| EncodedHuffmanValue(0x3f8, 10), |
| EncodedHuffmanValue(0x3f9, 10), |
| EncodedHuffmanValue(0xffa, 12), |
| EncodedHuffmanValue(0x1ff9, 13), |
| EncodedHuffmanValue(0x15, 6), |
| EncodedHuffmanValue(0xf8, 8), |
| EncodedHuffmanValue(0x7fa, 11), |
| EncodedHuffmanValue(0x3fa, 10), |
| EncodedHuffmanValue(0x3fb, 10), |
| EncodedHuffmanValue(0xf9, 8), |
| EncodedHuffmanValue(0x7fb, 11), |
| EncodedHuffmanValue(0xfa, 8), |
| EncodedHuffmanValue(0x16, 6), |
| EncodedHuffmanValue(0x17, 6), |
| EncodedHuffmanValue(0x18, 6), |
| EncodedHuffmanValue(0x0, 5), |
| EncodedHuffmanValue(0x1, 5), |
| EncodedHuffmanValue(0x2, 5), |
| EncodedHuffmanValue(0x19, 6), |
| EncodedHuffmanValue(0x1a, 6), |
| EncodedHuffmanValue(0x1b, 6), |
| EncodedHuffmanValue(0x1c, 6), |
| EncodedHuffmanValue(0x1d, 6), |
| EncodedHuffmanValue(0x1e, 6), |
| EncodedHuffmanValue(0x1f, 6), |
| EncodedHuffmanValue(0x5c, 7), |
| EncodedHuffmanValue(0xfb, 8), |
| EncodedHuffmanValue(0x7ffc, 15), |
| EncodedHuffmanValue(0x20, 6), |
| EncodedHuffmanValue(0xffb, 12), |
| EncodedHuffmanValue(0x3fc, 10), |
| EncodedHuffmanValue(0x1ffa, 13), |
| EncodedHuffmanValue(0x21, 6), |
| EncodedHuffmanValue(0x5d, 7), |
| EncodedHuffmanValue(0x5e, 7), |
| EncodedHuffmanValue(0x5f, 7), |
| EncodedHuffmanValue(0x60, 7), |
| EncodedHuffmanValue(0x61, 7), |
| EncodedHuffmanValue(0x62, 7), |
| EncodedHuffmanValue(0x63, 7), |
| EncodedHuffmanValue(0x64, 7), |
| EncodedHuffmanValue(0x65, 7), |
| EncodedHuffmanValue(0x66, 7), |
| EncodedHuffmanValue(0x67, 7), |
| EncodedHuffmanValue(0x68, 7), |
| EncodedHuffmanValue(0x69, 7), |
| EncodedHuffmanValue(0x6a, 7), |
| EncodedHuffmanValue(0x6b, 7), |
| EncodedHuffmanValue(0x6c, 7), |
| EncodedHuffmanValue(0x6d, 7), |
| EncodedHuffmanValue(0x6e, 7), |
| EncodedHuffmanValue(0x6f, 7), |
| EncodedHuffmanValue(0x70, 7), |
| EncodedHuffmanValue(0x71, 7), |
| EncodedHuffmanValue(0x72, 7), |
| EncodedHuffmanValue(0xfc, 8), |
| EncodedHuffmanValue(0x73, 7), |
| EncodedHuffmanValue(0xfd, 8), |
| EncodedHuffmanValue(0x1ffb, 13), |
| EncodedHuffmanValue(0x7fff0, 19), |
| EncodedHuffmanValue(0x1ffc, 13), |
| EncodedHuffmanValue(0x3ffc, 14), |
| EncodedHuffmanValue(0x22, 6), |
| EncodedHuffmanValue(0x7ffd, 15), |
| EncodedHuffmanValue(0x3, 5), |
| EncodedHuffmanValue(0x23, 6), |
| EncodedHuffmanValue(0x4, 5), |
| EncodedHuffmanValue(0x24, 6), |
| EncodedHuffmanValue(0x5, 5), |
| EncodedHuffmanValue(0x25, 6), |
| EncodedHuffmanValue(0x26, 6), |
| EncodedHuffmanValue(0x27, 6), |
| EncodedHuffmanValue(0x6, 5), |
| EncodedHuffmanValue(0x74, 7), |
| EncodedHuffmanValue(0x75, 7), |
| EncodedHuffmanValue(0x28, 6), |
| EncodedHuffmanValue(0x29, 6), |
| EncodedHuffmanValue(0x2a, 6), |
| EncodedHuffmanValue(0x7, 5), |
| EncodedHuffmanValue(0x2b, 6), |
| EncodedHuffmanValue(0x76, 7), |
| EncodedHuffmanValue(0x2c, 6), |
| EncodedHuffmanValue(0x8, 5), |
| EncodedHuffmanValue(0x9, 5), |
| EncodedHuffmanValue(0x2d, 6), |
| EncodedHuffmanValue(0x77, 7), |
| EncodedHuffmanValue(0x78, 7), |
| EncodedHuffmanValue(0x79, 7), |
| EncodedHuffmanValue(0x7a, 7), |
| EncodedHuffmanValue(0x7b, 7), |
| EncodedHuffmanValue(0x7ffe, 15), |
| EncodedHuffmanValue(0x7fc, 11), |
| EncodedHuffmanValue(0x3ffd, 14), |
| EncodedHuffmanValue(0x1ffd, 13), |
| EncodedHuffmanValue(0xffffffc, 28), |
| EncodedHuffmanValue(0xfffe6, 20), |
| EncodedHuffmanValue(0x3fffd2, 22), |
| EncodedHuffmanValue(0xfffe7, 20), |
| EncodedHuffmanValue(0xfffe8, 20), |
| EncodedHuffmanValue(0x3fffd3, 22), |
| EncodedHuffmanValue(0x3fffd4, 22), |
| EncodedHuffmanValue(0x3fffd5, 22), |
| EncodedHuffmanValue(0x7fffd9, 23), |
| EncodedHuffmanValue(0x3fffd6, 22), |
| EncodedHuffmanValue(0x7fffda, 23), |
| EncodedHuffmanValue(0x7fffdb, 23), |
| EncodedHuffmanValue(0x7fffdc, 23), |
| EncodedHuffmanValue(0x7fffdd, 23), |
| EncodedHuffmanValue(0x7fffde, 23), |
| EncodedHuffmanValue(0xffffeb, 24), |
| EncodedHuffmanValue(0x7fffdf, 23), |
| EncodedHuffmanValue(0xffffec, 24), |
| EncodedHuffmanValue(0xffffed, 24), |
| EncodedHuffmanValue(0x3fffd7, 22), |
| EncodedHuffmanValue(0x7fffe0, 23), |
| EncodedHuffmanValue(0xffffee, 24), |
| EncodedHuffmanValue(0x7fffe1, 23), |
| EncodedHuffmanValue(0x7fffe2, 23), |
| EncodedHuffmanValue(0x7fffe3, 23), |
| EncodedHuffmanValue(0x7fffe4, 23), |
| EncodedHuffmanValue(0x1fffdc, 21), |
| EncodedHuffmanValue(0x3fffd8, 22), |
| EncodedHuffmanValue(0x7fffe5, 23), |
| EncodedHuffmanValue(0x3fffd9, 22), |
| EncodedHuffmanValue(0x7fffe6, 23), |
| EncodedHuffmanValue(0x7fffe7, 23), |
| EncodedHuffmanValue(0xffffef, 24), |
| EncodedHuffmanValue(0x3fffda, 22), |
| EncodedHuffmanValue(0x1fffdd, 21), |
| EncodedHuffmanValue(0xfffe9, 20), |
| EncodedHuffmanValue(0x3fffdb, 22), |
| EncodedHuffmanValue(0x3fffdc, 22), |
| EncodedHuffmanValue(0x7fffe8, 23), |
| EncodedHuffmanValue(0x7fffe9, 23), |
| EncodedHuffmanValue(0x1fffde, 21), |
| EncodedHuffmanValue(0x7fffea, 23), |
| EncodedHuffmanValue(0x3fffdd, 22), |
| EncodedHuffmanValue(0x3fffde, 22), |
| EncodedHuffmanValue(0xfffff0, 24), |
| EncodedHuffmanValue(0x1fffdf, 21), |
| EncodedHuffmanValue(0x3fffdf, 22), |
| EncodedHuffmanValue(0x7fffeb, 23), |
| EncodedHuffmanValue(0x7fffec, 23), |
| EncodedHuffmanValue(0x1fffe0, 21), |
| EncodedHuffmanValue(0x1fffe1, 21), |
| EncodedHuffmanValue(0x3fffe0, 22), |
| EncodedHuffmanValue(0x1fffe2, 21), |
| EncodedHuffmanValue(0x7fffed, 23), |
| EncodedHuffmanValue(0x3fffe1, 22), |
| EncodedHuffmanValue(0x7fffee, 23), |
| EncodedHuffmanValue(0x7fffef, 23), |
| EncodedHuffmanValue(0xfffea, 20), |
| EncodedHuffmanValue(0x3fffe2, 22), |
| EncodedHuffmanValue(0x3fffe3, 22), |
| EncodedHuffmanValue(0x3fffe4, 22), |
| EncodedHuffmanValue(0x7ffff0, 23), |
| EncodedHuffmanValue(0x3fffe5, 22), |
| EncodedHuffmanValue(0x3fffe6, 22), |
| EncodedHuffmanValue(0x7ffff1, 23), |
| EncodedHuffmanValue(0x3ffffe0, 26), |
| EncodedHuffmanValue(0x3ffffe1, 26), |
| EncodedHuffmanValue(0xfffeb, 20), |
| EncodedHuffmanValue(0x7fff1, 19), |
| EncodedHuffmanValue(0x3fffe7, 22), |
| EncodedHuffmanValue(0x7ffff2, 23), |
| EncodedHuffmanValue(0x3fffe8, 22), |
| EncodedHuffmanValue(0x1ffffec, 25), |
| EncodedHuffmanValue(0x3ffffe2, 26), |
| EncodedHuffmanValue(0x3ffffe3, 26), |
| EncodedHuffmanValue(0x3ffffe4, 26), |
| EncodedHuffmanValue(0x7ffffde, 27), |
| EncodedHuffmanValue(0x7ffffdf, 27), |
| EncodedHuffmanValue(0x3ffffe5, 26), |
| EncodedHuffmanValue(0xfffff1, 24), |
| EncodedHuffmanValue(0x1ffffed, 25), |
| EncodedHuffmanValue(0x7fff2, 19), |
| EncodedHuffmanValue(0x1fffe3, 21), |
| EncodedHuffmanValue(0x3ffffe6, 26), |
| EncodedHuffmanValue(0x7ffffe0, 27), |
| EncodedHuffmanValue(0x7ffffe1, 27), |
| EncodedHuffmanValue(0x3ffffe7, 26), |
| EncodedHuffmanValue(0x7ffffe2, 27), |
| EncodedHuffmanValue(0xfffff2, 24), |
| EncodedHuffmanValue(0x1fffe4, 21), |
| EncodedHuffmanValue(0x1fffe5, 21), |
| EncodedHuffmanValue(0x3ffffe8, 26), |
| EncodedHuffmanValue(0x3ffffe9, 26), |
| EncodedHuffmanValue(0xffffffd, 28), |
| EncodedHuffmanValue(0x7ffffe3, 27), |
| EncodedHuffmanValue(0x7ffffe4, 27), |
| EncodedHuffmanValue(0x7ffffe5, 27), |
| EncodedHuffmanValue(0xfffec, 20), |
| EncodedHuffmanValue(0xfffff3, 24), |
| EncodedHuffmanValue(0xfffed, 20), |
| EncodedHuffmanValue(0x1fffe6, 21), |
| EncodedHuffmanValue(0x3fffe9, 22), |
| EncodedHuffmanValue(0x1fffe7, 21), |
| EncodedHuffmanValue(0x1fffe8, 21), |
| EncodedHuffmanValue(0x7ffff3, 23), |
| EncodedHuffmanValue(0x3fffea, 22), |
| EncodedHuffmanValue(0x3fffeb, 22), |
| EncodedHuffmanValue(0x1ffffee, 25), |
| EncodedHuffmanValue(0x1ffffef, 25), |
| EncodedHuffmanValue(0xfffff4, 24), |
| EncodedHuffmanValue(0xfffff5, 24), |
| EncodedHuffmanValue(0x3ffffea, 26), |
| EncodedHuffmanValue(0x7ffff4, 23), |
| EncodedHuffmanValue(0x3ffffeb, 26), |
| EncodedHuffmanValue(0x7ffffe6, 27), |
| EncodedHuffmanValue(0x3ffffec, 26), |
| EncodedHuffmanValue(0x3ffffed, 26), |
| EncodedHuffmanValue(0x7ffffe7, 27), |
| EncodedHuffmanValue(0x7ffffe8, 27), |
| EncodedHuffmanValue(0x7ffffe9, 27), |
| EncodedHuffmanValue(0x7ffffea, 27), |
| EncodedHuffmanValue(0x7ffffeb, 27), |
| EncodedHuffmanValue(0xffffffe, 28), |
| EncodedHuffmanValue(0x7ffffec, 27), |
| EncodedHuffmanValue(0x7ffffed, 27), |
| EncodedHuffmanValue(0x7ffffee, 27), |
| EncodedHuffmanValue(0x7ffffef, 27), |
| EncodedHuffmanValue(0x7fffff0, 27), |
| EncodedHuffmanValue(0x3ffffee, 26), |
| EncodedHuffmanValue(0x3fffffff, 30), |
| ]; |
