chat-server/node_modules/node-rsa/src/utils.js

108 lines
2.6 KiB
JavaScript

/*
* Utils functions
*
*/
var crypt = require('crypto');
/**
* Break string str each maxLen symbols
* @param str
* @param maxLen
* @returns {string}
*/
module.exports.linebrk = function (str, maxLen) {
var res = '';
var i = 0;
while (i + maxLen < str.length) {
res += str.substring(i, i + maxLen) + "\n";
i += maxLen;
}
return res + str.substring(i, str.length);
};
module.exports.detectEnvironment = function () {
if (typeof(window) !== 'undefined' && window && !(process && process.title === 'node')) {
return 'browser';
}
return 'node';
};
/**
* Trying get a 32-bit unsigned integer from the partial buffer
* @param buffer
* @param offset
* @returns {Number}
*/
module.exports.get32IntFromBuffer = function (buffer, offset) {
offset = offset || 0;
var size = 0;
if ((size = buffer.length - offset) > 0) {
if (size >= 4) {
return buffer.readUInt32BE(offset);
} else {
var res = 0;
for (var i = offset + size, d = 0; i > offset; i--, d += 2) {
res += buffer[i - 1] * Math.pow(16, d);
}
return res;
}
} else {
return NaN;
}
};
module.exports._ = {
isObject: function (value) {
var type = typeof value;
return !!value && (type == 'object' || type == 'function');
},
isString: function (value) {
return typeof value == 'string' || value instanceof String;
},
isNumber: function (value) {
return typeof value == 'number' || !isNaN(parseFloat(value)) && isFinite(value);
},
/**
* Returns copy of `obj` without `removeProp` field.
* @param obj
* @param removeProp
* @returns Object
*/
omit: function (obj, removeProp) {
var newObj = {};
for (var prop in obj) {
if (!obj.hasOwnProperty(prop) || prop === removeProp) {
continue;
}
newObj[prop] = obj[prop];
}
return newObj;
}
};
/**
* Strips everything around the opening and closing lines, including the lines
* themselves.
*/
module.exports.trimSurroundingText = function (data, opening, closing) {
var trimStartIndex = 0;
var trimEndIndex = data.length;
var openingBoundaryIndex = data.indexOf(opening);
if (openingBoundaryIndex >= 0) {
trimStartIndex = openingBoundaryIndex + opening.length;
}
var closingBoundaryIndex = data.indexOf(closing, openingBoundaryIndex);
if (closingBoundaryIndex >= 0) {
trimEndIndex = closingBoundaryIndex;
}
return data.substring(trimStartIndex, trimEndIndex);
}