Created
November 8, 2017 23:11
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Hashed port number collisions
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var crypto = require('crypto'); | |
function hash(s) { | |
return (parseInt(crypto.createHash('sha1').update(s || '').digest('hex'), 16) % 50000) + 10000; | |
} | |
var nums = {}; | |
var lookup = {}; | |
for (var i = 1; i <= 100; i++) { | |
var r = parseInt(Math.random() * 1e4); | |
if (nums[r]) { | |
i--; | |
continue; | |
} | |
var s = 'com.testapp' + r; | |
var port = hash(s.split().reverse().join()); | |
if (lookup[port]) { | |
console.log(s + '\t= ' + port + ' COLLISION! ' + lookup[port]); | |
} else { | |
console.log(s + '\t= ' + port); | |
lookup[port] = s; | |
} | |
} |
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