37 lines
1.1 KiB
JavaScript
37 lines
1.1 KiB
JavaScript
/**
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* Implements proof of work.
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* @see {@link https://bitmessage.org/wiki/Proof_of_work}
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* @module bitmessage/pow
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*/
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"use strict";
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var platform = require("./platform");
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var DEFAULT_TRIALS_PER_BYTE = 1000;
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var DEFAULT_EXTRA_BYTES = 1000;
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/**
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* Calculate target
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* @param {{ttl: number, payloadLength: number}} opts - Target options
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* @return {number} Target.
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*/
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// Just a wrapper around platform-specific implementation.
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exports.getTarget = function(opts) {
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var nonceTrialsPerByte = opts.nonceTrialsPerByte;
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// Automatically raise lower values per spec.
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if (!nonceTrialsPerByte || nonceTrialsPerByte < DEFAULT_TRIALS_PER_BYTE) {
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nonceTrialsPerByte = DEFAULT_TRIALS_PER_BYTE;
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}
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var payloadLengthExtraBytes = opts.payloadLengthExtraBytes;
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if (!payloadLengthExtraBytes || payloadLengthExtraBytes < DEFAULT_EXTRA_BYTES) {
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payloadLengthExtraBytes = DEFAULT_EXTRA_BYTES;
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}
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return platform.getTarget({
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ttl: opts.ttl,
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payloadLength: opts.payloadLength,
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nonceTrialsPerByte: nonceTrialsPerByte,
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payloadLengthExtraBytes: payloadLengthExtraBytes,
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});
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};
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