35 lines
1005 B
JavaScript
35 lines
1005 B
JavaScript
/**
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* Copyright (c) 2011-2016 bitcoinjs-lib contributors
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*/
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// https://github.com/feross/buffer/blob/master/index.js#L1127
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function verifuint (value, max) {
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if (typeof value !== 'number') throw new Error('cannot write a non-number as a number')
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if (value < 0) throw new Error('specified a negative value for writing an unsigned value')
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if (value > max) throw new Error('RangeError: value out of range')
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if (Math.floor(value) !== value) throw new Error('value has a fractional component')
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}
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function readUInt64LE (buffer, offset) {
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var a = buffer.readUInt32LE(offset)
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var b = buffer.readUInt32LE(offset + 4)
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b *= 0x100000000
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verifuint(b + a, 0x001fffffffffffff)
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return b + a
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}
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function writeUInt64LE (buffer, value, offset) {
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verifuint(value, 0x001fffffffffffff)
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buffer.writeInt32LE(value & -1, offset)
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buffer.writeUInt32LE(Math.floor(value / 0x100000000), offset + 4)
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return offset + 8
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}
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module.exports = {
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readUInt64LE: readUInt64LE,
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writeUInt64LE: writeUInt64LE
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}
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