appliedcrypto/z_associated/projects/node_modules/sha256/lib/nodecrypto.js

var crypto = require('crypto');

// Node.js has its own Crypto function that can handle this natively
var sha256 = module.exports = function(message, options) {
	var c = crypto.createHash('sha256');
	
	if (Buffer.isBuffer(message)) {
		c.update(message);
	} else if (Array.isArray(message)) {
		// Array of byte values
		c.update(new Buffer(message));
	} else {
		// Otherwise, treat as a binary string
		c.update(new Buffer(message, 'binary'));
	}
	var buf = c.digest();
	
	if (options && options.asBytes) {
		// Array of bytes as decimal integers
		var a = [];
		for(var i = 0; i < buf.length; i++) {
			a.push(buf[i]);
		}
		return a;
	} else if (options && options.asString) {
		// Binary string
		return buf.toString('binary');
	} else {
		// String of hex characters
		return buf.toString('hex');
	}
}

sha256.x2 = function(message, options) {
	return sha256(sha256(message, { asBytes:true }), options)
}