Removes redundant convert functions

src/convert.js

@@ -24,15 +24,6 @@ function hexToBytes(hex) {
   })
 }
 
-/**
- * Create a byte array representing a number with the given length
- */
-function numToBytes(num, bytes) {
-  if (bytes === undefined) bytes = 8
-  if (bytes === 0) return []
-  return [num % 256].concat(numToBytes(Math.floor(num / 256), bytes - 1))
-}
-
 /**
  * Convert a byte array to the number that it represents
  */
@@ -41,42 +32,6 @@ function bytesToNum(bytes) {
   return bytes[0] + 256 * bytesToNum(bytes.slice(1))
 }
 
-/**
- * Turn an integer into a "var_int".
- *
- * "var_int" is a variable length integer used by Bitcoin's binary format.
- *
- * Returns a byte array.
- */
-function numToVarInt(num) {
-  if (num < 253) return [num]
-  if (num < 65536) return [253].concat(numToBytes(num, 2))
-  if (num < 4294967296) return [254].concat(numToBytes(num, 4))
-  return [255].concat(numToBytes(num, 8))
-}
-
-/**
- * Turn an VarInt into an integer
- *
- * "var_int" is a variable length integer used by Bitcoin's binary format.
- *
- * Returns { bytes: bytesUsed, number: theNumber }
- */
-function varIntToNum(bytes) {
-  var prefix = bytes[0]
-
-  var viBytes =
-      prefix < 253   ? bytes.slice(0, 1)
-    : prefix === 253 ? bytes.slice(1, 3)
-    : prefix === 254 ? bytes.slice(1, 5)
-    : bytes.slice(1, 9)
-
-  return {
-    bytes: prefix < 253 ? viBytes : bytes.slice(0, viBytes.length + 1),
-    number: bytesToNum(viBytes)
-  }
-}
-
 function bytesToWords(bytes) {
   assert(Array.isArray(bytes) || Buffer.isBuffer(bytes), 'Input must be a byte array')
   var words = []
@@ -110,10 +65,7 @@ module.exports = {
   lpad: lpad,
   bytesToHex: bytesToHex,
   hexToBytes: hexToBytes,
-  numToBytes: numToBytes,
   bytesToNum: bytesToNum,
-  numToVarInt: numToVarInt,
-  varIntToNum: varIntToNum,
   bytesToWords: bytesToWords,
   wordsToBytes: wordsToBytes,
   bytesToWordArray: bytesToWordArray,

src/hdwallet.js

@@ -179,10 +179,11 @@ HDWallet.prototype.toBase58 = function(priv) {
 }
 
 HDWallet.prototype.derive = function(i) {
-  var iBytes = convert.numToBytes(i, 4).reverse()
+  var IB = new Buffer(4)
-    , cPar = this.chaincode
+  IB.writeUInt32BE(i, 0)
-    , usePriv = i >= HDWallet.HIGHEST_BIT
+
-    , SHA512 = CJS.algo.SHA512
+  var cPar = this.chaincode
+  var usePriv = i >= HDWallet.HIGHEST_BIT
 
   var I
   if (usePriv) {
@@ -191,18 +192,18 @@ HDWallet.prototype.derive = function(i) {
     // If 1, private derivation is used:
     // let I = HMAC-SHA512(Key = cpar, Data = 0x00 || kpar || i) [Note:]
     var kPar = this.priv.toBuffer().slice(0, 32)
-    kPar = Array.prototype.slice.call(kPar)
+    IB = Buffer.concat([new Buffer([0]), kPar, IB], 37)
 
     // FIXME: Dislikes buffers
-    I = HmacFromBytesToBytes(SHA512, [0].concat(kPar, iBytes), cPar)
+    I = HmacFromBytesToBytes(CJS.algo.SHA512, Array.prototype.slice.call(IB), cPar)
   } else {
     // If 0, public derivation is used:
     // let I = HMAC-SHA512(Key = cpar, Data = χ(kpar*G) || i)
     var KPar = this.pub.toBuffer()
-    KPar = Array.prototype.slice.call(KPar)
+    IB = Buffer.concat([KPar, IB])
 
     // FIXME: Dislikes buffers
-    I = HmacFromBytesToBytes(SHA512, KPar.concat(iBytes), cPar)
+    I = HmacFromBytesToBytes(CJS.algo.SHA512, Array.prototype.slice.call(IB), cPar)
   }
 
 

src/message.js

@@ -1,24 +1,20 @@
 /// Implements Bitcoin's feature for signing arbitrary messages.
 
 var Address = require('./address')
-var convert = require('./convert')
+var BufferExt = require('./buffer')
 var crypto = require('./crypto')
 var ecdsa = require('./ecdsa')
 var ECPubKey = require('./eckey').ECPubKey
 
-// FIXME: magicHash is incompatible with other magic messages
+// FIXME: incompatible with other networks (Litecoin etc)
-var magicBytes = new Buffer('Bitcoin Signed Message:\n')
+var magicBuffer = new Buffer('\x18Bitcoin Signed Message:\n')
 
 function magicHash(message) {
-  var messageBytes = new Buffer(message)
+  var mB = new Buffer(message)
-
+  var mVI = new Buffer(BufferExt.varIntSize(mB.length))
-  var buffer = Buffer.concat([
+  BufferExt.writeVarInt(mVI, mB.length, 0)
-    new Buffer(convert.numToVarInt(magicBytes.length)),
-    magicBytes,
-    new Buffer(convert.numToVarInt(messageBytes.length)),
-    messageBytes
-  ])
 
+  var buffer = Buffer.concat([magicBuffer, mVI, mB])
   return crypto.hash256(buffer)
 }
 

test/convert.js

@@ -52,67 +52,6 @@ describe('convert', function() {
     })
   })
 
-  describe('numToVarInt', function() {
-    describe('works', function() {
-      var data = [
-        0, 128, 252, // 8-bit
-        256, 512, 1024, // 16-bit
-        65541, // 32-bit
-        4294967299, // 64-bit
-      ]
-      var expected = [
-        [0], [128], [252], // 8-bit
-        [253, 0, 1], [253, 0, 2], [253, 0, 4], // 16-bit
-        [254, 5, 0, 1, 0], // 32-bit
-        [255, 3, 0, 0, 0, 1, 0, 0, 0] // 64-bit
-      ]
-
-      for (var i = 0; i < data.length; ++i) {
-        var actual = convert.numToVarInt(data[i])
-        assert.deepEqual(actual, expected[i])
-      }
-    })
-  })
-
-  describe('varIntToNum', function() {
-    it('works on valid input', function() {
-      var data = [
-        [0], [128], [252], // 8-bit
-        [253, 0, 1], [253, 0, 2], [253, 0, 4], // 16-bit
-        [254, 5, 0, 1, 0], // 32-bit
-        [255, 3, 0, 0, 0, 1, 0, 0, 0] // 64-bit
-      ]
-      var expected = [
-        0, 128, 252, // 8-bit
-        256, 512, 1024, // 16-bit
-        65541, // 32-bit
-        4294967299, // 64-bit
-      ]
-
-      for (var i = 0; i < data.length; ++i) {
-        var actual = convert.varIntToNum(data[i])
-        assert.equal(actual.number, expected[i])
-        assert.deepEqual(actual.bytes, data[i])
-      }
-    })
-
-    it('uses only what is necessary', function() {
-      var data = [
-        [0, 99],
-        [253, 0, 1, 99],
-        [254, 5, 0, 1, 0, 99],
-        [255, 3, 0, 0, 0, 1, 0, 0, 0, 99]
-      ]
-      var expected = [0, 256, 65541, 4294967299]
-
-      for (var i = 0; i < data.length; ++i) {
-        var actual = convert.varIntToNum(data[i])
-        assert.equal(actual.number, expected[i])
-        assert.deepEqual(actual.bytes, data[i].slice(0, -1))
-      }
-    })
-  })
-
   describe('reverseEndian', function() {
     it('works', function() {
       var bigEndian = "6a4062273ac4f9ea4ffca52d9fd102b08f6c32faa0a4d1318e3a7b2e437bb9c7"