use varuint-bitcoin

This commit is contained in:
Daniel Cousens 2016-10-06 21:53:48 +11:00
parent 038c0f08d2
commit 29a865788d
5 changed files with 26 additions and 102 deletions

View file

@ -1,12 +1,5 @@
var opcodes = require('./opcodes.json')
// https://github.com/feross/buffer/blob/master/index.js#L1127
function verifuint (value, max) {
if (typeof value !== 'number') throw new Error('cannot write a non-number as a number')
if (value < 0) throw new Error('specified a negative value for writing an unsigned value')
if (value > max) throw new Error('value is larger than maximum value for type')
if (Math.floor(value) !== value) throw new Error('value has a fractional component')
}
var varuint = require('varuint-bitcoin')
function pushDataSize (i) {
return i < opcodes.OP_PUSHDATA1 ? 1
@ -52,6 +45,14 @@ function readPushDataInt (buffer, offset) {
}
}
// https://github.com/feross/buffer/blob/master/index.js#L1127
function verifuint (value, max) {
if (typeof value !== 'number') throw new Error('cannot write a non-number as a number')
if (value < 0) throw new Error('specified a negative value for writing an unsigned value')
if (value > max) throw new Error('RangeError: value out of range')
if (Math.floor(value) !== value) throw new Error('value has a fractional component')
}
function readUInt64LE (buffer, offset) {
var a = buffer.readUInt32LE(offset)
var b = buffer.readUInt32LE(offset + 4)
@ -62,37 +63,6 @@ function readUInt64LE (buffer, offset) {
return b + a
}
function readVarInt (buffer, offset) {
var t = buffer.readUInt8(offset)
var number, size
// 8 bit
if (t < 253) {
number = t
size = 1
// 16 bit
} else if (t < 254) {
number = buffer.readUInt16LE(offset + 1)
size = 3
// 32 bit
} else if (t < 255) {
number = buffer.readUInt32LE(offset + 1)
size = 5
// 64 bit
} else {
number = readUInt64LE(buffer, offset + 1)
size = 9
}
return {
number: number,
size: size
}
}
function writePushDataInt (buffer, number, offset) {
var size = pushDataSize(number)
@ -126,45 +96,20 @@ function writeUInt64LE (buffer, value, offset) {
buffer.writeUInt32LE(Math.floor(value / 0x100000000), offset + 4)
}
function varIntSize (i) {
return i < 253 ? 1
: i < 0x10000 ? 3
: i < 0x100000000 ? 5
: 9
}
// TODO: remove in 4.0.0?
function readVarInt (buffer, offset) {
var result = varuint.decode(buffer, offset)
function writeVarInt (buffer, number, offset) {
var size = varIntSize(number)
// 8 bit
if (size === 1) {
buffer.writeUInt8(number, offset)
// 16 bit
} else if (size === 3) {
buffer.writeUInt8(253, offset)
buffer.writeUInt16LE(number, offset + 1)
// 32 bit
} else if (size === 5) {
buffer.writeUInt8(254, offset)
buffer.writeUInt32LE(number, offset + 1)
// 64 bit
} else {
buffer.writeUInt8(255, offset)
writeUInt64LE(buffer, number, offset + 1)
return {
number: result,
size: varuint.decode.bytes
}
return size
}
function varIntBuffer (i) {
var size = varIntSize(i)
var buffer = new Buffer(size)
writeVarInt(buffer, i, 0)
return buffer
// TODO: remove in 4.0.0?
function writeVarInt (buffer, number, offset) {
varuint.encode(number, buffer, offset)
return varuint.encode.bytes
}
module.exports = {
@ -172,13 +117,9 @@ module.exports = {
readPushDataInt: readPushDataInt,
readUInt64LE: readUInt64LE,
readVarInt: readVarInt,
varIntBuffer: varIntBuffer,
varIntSize: varIntSize,
varIntBuffer: varuint.encode,
varIntSize: varuint.encodingLength,
writePushDataInt: writePushDataInt,
writeUInt64LE: writeUInt64LE,
writeVarInt: writeVarInt,
// TODO: remove in 3.0.0
equal: function BufferEquals (a, b) { return a.equals(b) },
reverse: require('buffer-reverse')
writeVarInt: writeVarInt
}