first commit

app_vue/node_modules/hpack.js/lib/hpack/encoder.js

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+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);
+};