7d73e60f60
Adds Buffer.prototype.swap16() and Buffer.prototype.swap32() methods that mutate the Buffer instance in-place by swapping the 16-bit and 32-bit byte-order. Example: ```js const buf = Buffer([0x1, 0x2, 0x3, 0x4]); buf.swap16(); console.log(buf); // prints Buffer(0x2, 0x1, 0x4, 0x3); buf.swap32(); console.log(buf); // prints Buffer(0x3, 0x4, 0x1, 0x2); ``` PR-URL: https://github.com/nodejs/node/pull/5724 Reviewed-By: Trevor Norris <trev.norris@gmail.com>
61 lines
1.4 KiB
JavaScript
61 lines
1.4 KiB
JavaScript
'use strict';
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const common = require('../common.js');
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const bench = common.createBenchmark(main, {
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method: ['swap16', 'swap32', 'htons', 'htonl'],
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len: [4, 64, 512, 768, 1024, 1536, 2056, 4096, 8192],
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n: [1e6]
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});
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// The htons and htonl methods below are used to benchmark the
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// performance difference between doing the byteswap in pure
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// javascript regardless of Buffer size as opposed to dropping
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// down to the native layer for larger Buffer sizes.
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Buffer.prototype.htons = function htons() {
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if (this.length % 2 !== 0)
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throw new RangeError();
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for (var i = 0, n = 0; i < this.length; i += 2) {
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n = this[i];
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this[i] = this[i + 1];
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this[i + 1] = n;
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}
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return this;
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};
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Buffer.prototype.htonl = function htonl() {
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if (this.length % 2 !== 0)
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throw new RangeError();
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for (var i = 0, n = 0; i < this.length; i += 4) {
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n = this[i];
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this[i] = this[i + 3];
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this[i + 3] = n;
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n = this[i + 1];
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this[i + 1] = this[i + 2];
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this[i + 2] = n;
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}
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return this;
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};
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function createBuffer(len) {
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const buf = Buffer.allocUnsafe(len);
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for (var i = 1; i <= len; i++)
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buf[i - 1] = i;
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return buf;
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}
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function bufferSwap(n, buf, method) {
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for (var i = 1; i <= n; i++)
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buf[method]();
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}
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function main(conf) {
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const method = conf.method;
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const len = conf.len | 0;
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const n = conf.n | 0;
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const buf = createBuffer(len);
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bench.start();
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bufferSwap(n, buf, method);
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bench.end(n);
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}
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