26 lines
680 B
JavaScript
26 lines
680 B
JavaScript
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'use strict'
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const { MAX_MSGID } = require('../constants')
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/**
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* Compare a reference id with another id to determine "greater than or equal"
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* between the two values according to a sliding window.
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*
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* @param {integer} ref
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* @param {integer} comp
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*
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* @returns {boolean} `true` if the `comp` value is >= to the `ref` value
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* within the computed window, otherwise `false`.
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*/
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module.exports = function geWindow (ref, comp) {
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let max = ref + Math.floor(MAX_MSGID / 2)
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const min = ref
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if (max >= MAX_MSGID) {
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// Handle roll-over
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max = max - MAX_MSGID - 1
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return ((comp <= max) || (comp >= min))
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} else {
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return ((comp <= max) && (comp >= min))
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}
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}
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