�PNG  IHDR��;���IDATx��ܻn�0���K�� �)(�pA��� ���7�LeG{�� �§㻢|��ذaÆ 6lذaÆ 6lذaÆ 6lom��$^�y���ذag�5bÆ 6lذaÆ 6lذa{���� 6lذaÆ �`����}H�Fkm�,�m����Ӫ���ô�ô!� �x�|'ܢ˟;�E:���9�&ᶒ�}�{�v]�n&�6� �h��_��t�ڠ͵-ҫ���Z;��Z$�.�P���k�ž)�!��o���>}l�eQfJ�T��u і���چ��\��X=8��Rن4`Vw�l�>����n�G�^��i�s��"ms�$�u��i��?w�bs[m�6�K4���O���.�4��%����/����b�C%��t ��M�ז� �-l�G6�mrz2���s�%�9��s@���-�k�9�=���)������k�B5����\��+͂�Zsٲ ��Rn��~G���R���C����� �wIcI��n7jJ���hۛNCS|���j0��8y�iHKֶۛ�k�Ɉ+;Sz������L/��F�*\��Ԕ�#"5��m�2��[S��������=�g��n�a�P�e�ғ�L�� lذaÆ 6l�^k��̱aÆ 6lذaÆ 6lذa;���� �_��ذaÆ 6lذaÆ 6lذaÆ ���R���IEND�B` var hpack = require('../hpack'); var utils = hpack.utils; var huffman = hpack.huffman.encode; var assert = utils.assert; var WBuf = require('wbuf'); function Encoder() { this.buffer = new WBuf(); this.word = 0; this.bitOffset = 0; } module.exports = Encoder; Encoder.create = function create() { return new Encoder(); }; Encoder.prototype.render = function render() { return this.buffer.render(); }; Encoder.prototype.encodeBit = function encodeBit(bit) { var octet; this.word <<= 1; this.word |= bit; this.bitOffset++; if (this.bitOffset === 8) { this.buffer.writeUInt8(this.word); this.word = 0; this.bitOffset = 0; } }; Encoder.prototype.encodeBits = function encodeBits(bits, len) { var left = bits; var leftLen = len; while (leftLen > 0) { var avail = Math.min(leftLen, 8 - this.bitOffset); var toWrite = left >>> (leftLen - avail); if (avail === 8) { this.buffer.writeUInt8(toWrite); } else { this.word <<= avail; this.word |= toWrite; this.bitOffset += avail; if (this.bitOffset === 8) { this.buffer.writeUInt8(this.word); this.word = 0; this.bitOffset = 0; } } leftLen -= avail; left &= (1 << leftLen) - 1; } }; // Just for testing Encoder.prototype.skipBits = function skipBits(num) { this.bitOffset += num; this.buffer.skip(this.bitOffset >> 3); this.bitOffset &= 0x7; }; Encoder.prototype.encodeInt = function encodeInt(num) { var prefix = 8 - this.bitOffset; // We are going to end up octet-aligned this.bitOffset = 0; var max = (1 << prefix) - 1; // Fast case - int fits into the prefix if (num < max) { this.buffer.writeUInt8((this.word << prefix) | num); return octet; } var left = num - max; this.buffer.writeUInt8((this.word << prefix) | max); do { var octet = left & 0x7f; left >>= 7; if (left !== 0) octet |= 0x80; this.buffer.writeUInt8(octet); } while (left !== 0); }; Encoder.prototype.encodeStr = function encodeStr(value, isHuffman) { this.encodeBit(isHuffman ? 1 : 0); if (!isHuffman) { this.buffer.reserve(value.length + 1); this.encodeInt(value.length); for (var i = 0; i < value.length; i++) this.buffer.writeUInt8(value[i]); return; } var codes = []; var len = 0; var pad = 0; for (var i = 0; i < value.length; i++) { var code = huffman[value[i]]; codes.push(code); len += code[0]; } if (len % 8 !== 0) pad = 8 - (len % 8); len += pad; this.buffer.reserve((len / 8) + 1); this.encodeInt(len / 8); for (var i = 0; i < codes.length; i++) { var code = codes[i]; this.encodeBits(code[1], code[0]); } // Append padding this.encodeBits(0xff >>> (8 - pad), pad); };