Revert "Add support for large integers"

lib/decode.js

@@ -0,0 +1,117 @@
+/**
+ * Decodes bencoded data.
+ *
+ * @param  {Buffer} data
+ * @param  {Number} start (optional)
+ * @param  {Number} end (optional)
+ * @param  {String} encoding (optional)
+ * @return {Object|Array|Buffer|String|Number}
+ */
+function decode (data, start, end, encoding) {
+  if (typeof start !== 'number' && encoding == null) {
+    encoding = start
+    start = undefined
+  }
+
+  if (typeof end !== 'number' && encoding == null) {
+    encoding = end
+    end = undefined
+  }
+
+  decode.position = 0
+  decode.encoding = encoding || null
+
+  decode.data = !(Buffer.isBuffer(data))
+    ? new Buffer(data)
+    : data.slice(start, end)
+
+  decode.bytes = decode.data.length
+
+  return decode.next()
+}
+
+decode.bytes = 0
+decode.position = 0
+decode.data = null
+decode.encoding = null
+
+decode.next = function () {
+  switch (decode.data[decode.position]) {
+    case 0x64:
+      return decode.dictionary()
+    case 0x6C:
+      return decode.list()
+    case 0x69:
+      return decode.integer()
+    default:
+      return decode.buffer()
+  }
+}
+
+decode.find = function (chr) {
+  var i = decode.position
+  var c = decode.data.length
+  var d = decode.data
+
+  while (i < c) {
+    if (d[i] === chr) return i
+    i++
+  }
+
+  throw new Error(
+    'Invalid data: Missing delimiter "' +
+    String.fromCharCode(chr) + '" [0x' +
+    chr.toString(16) + ']'
+  )
+}
+
+decode.dictionary = function () {
+  decode.position++
+
+  var dict = {}
+
+  while (decode.data[decode.position] !== 0x65) {
+    dict[decode.buffer()] = decode.next()
+  }
+
+  decode.position++
+
+  return dict
+}
+
+decode.list = function () {
+  decode.position++
+
+  var lst = []
+
+  while (decode.data[decode.position] !== 0x65) {
+    lst.push(decode.next())
+  }
+
+  decode.position++
+
+  return lst
+}
+
+decode.integer = function () {
+  var end = decode.find(0x65)
+  var number = decode.data.toString('ascii', decode.position + 1, end)
+
+  decode.position += end + 1 - decode.position
+
+  return parseInt(number, 10)
+}
+
+decode.buffer = function () {
+  var sep = decode.find(0x3A)
+  var length = parseInt(decode.data.toString('ascii', decode.position, sep), 10)
+  var end = ++sep + length
+
+  decode.position = end
+
+  return decode.encoding
+    ? decode.data.toString(decode.encoding, sep, end)
+    : decode.data.slice(sep, end)
+}
+
+module.exports = decode

lib/encode.js

@@ -0,0 +1,107 @@
+/**
+ * Encodes data in bencode.
+ *
+ * @param  {Buffer|Array|String|Object|Number|Boolean} data
+ * @return {Buffer}
+ */
+function encode (data, buffer, offset) {
+  var buffers = []
+  var result = null
+
+  encode._encode(buffers, data)
+  result = Buffer.concat(buffers)
+  encode.bytes = result.length
+
+  if (Buffer.isBuffer(buffer)) {
+    result.copy(buffer, offset)
+    return buffer
+  }
+
+  return result
+}
+
+encode.bytes = -1
+encode._floatConversionDetected = false
+
+encode._encode = function (buffers, data) {
+  if (Buffer.isBuffer(data)) {
+    buffers.push(new Buffer(data.length + ':'))
+    buffers.push(data)
+    return
+  }
+
+  switch (typeof data) {
+    case 'string':
+      encode.buffer(buffers, data)
+      break
+    case 'number':
+      encode.number(buffers, data)
+      break
+    case 'object':
+      data.constructor === Array
+        ? encode.list(buffers, data)
+        : encode.dict(buffers, data)
+      break
+    case 'boolean':
+      encode.number(buffers, data ? 1 : 0)
+      break
+  }
+}
+
+var buffE = new Buffer('e')
+var buffD = new Buffer('d')
+var buffL = new Buffer('l')
+
+encode.buffer = function (buffers, data) {
+  buffers.push(new Buffer(Buffer.byteLength(data) + ':' + data))
+}
+
+encode.number = function (buffers, data) {
+  var maxLo = 0x80000000
+  var hi = (data / maxLo) << 0
+  var lo = (data % maxLo) << 0
+  var val = hi * maxLo + lo
+
+  buffers.push(new Buffer('i' + val + 'e'))
+
+  if (val !== data && !encode._floatConversionDetected) {
+    encode._floatConversionDetected = true
+    console.warn(
+      'WARNING: Possible data corruption detected with value "' + data + '":',
+      'Bencoding only defines support for integers, value was converted to "' + val + '"'
+    )
+    console.trace()
+  }
+}
+
+encode.dict = function (buffers, data) {
+  buffers.push(buffD)
+
+  var j = 0
+  var k
+  // fix for issue #13 - sorted dicts
+  var keys = Object.keys(data).sort()
+  var kl = keys.length
+
+  for (; j < kl; j++) {
+    k = keys[j]
+    encode.buffer(buffers, k)
+    encode._encode(buffers, data[k])
+  }
+
+  buffers.push(buffE)
+}
+
+encode.list = function (buffers, data) {
+  var i = 0
+  var c = data.length
+  buffers.push(buffL)
+
+  for (; i < c; i++) {
+    encode._encode(buffers, data[i])
+  }
+
+  buffers.push(buffE)
+}
+
+module.exports = encode