thedesk/node_modules/jszip/lib/utils.js

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2018-08-05 02:26:34 +10:00
'use strict';
var support = require('./support');
var compressions = require('./compressions');
var nodeBuffer = require('./nodeBuffer');
/**
* Convert a string to a "binary string" : a string containing only char codes between 0 and 255.
* @param {string} str the string to transform.
* @return {String} the binary string.
*/
exports.string2binary = function(str) {
var result = "";
for (var i = 0; i < str.length; i++) {
result += String.fromCharCode(str.charCodeAt(i) & 0xff);
}
return result;
};
exports.arrayBuffer2Blob = function(buffer, mimeType) {
exports.checkSupport("blob");
mimeType = mimeType || 'application/zip';
try {
// Blob constructor
return new Blob([buffer], {
type: mimeType
});
}
catch (e) {
try {
// deprecated, browser only, old way
var Builder = window.BlobBuilder || window.WebKitBlobBuilder || window.MozBlobBuilder || window.MSBlobBuilder;
var builder = new Builder();
builder.append(buffer);
return builder.getBlob(mimeType);
}
catch (e) {
// well, fuck ?!
throw new Error("Bug : can't construct the Blob.");
}
}
};
/**
* The identity function.
* @param {Object} input the input.
* @return {Object} the same input.
*/
function identity(input) {
return input;
}
/**
* Fill in an array with a string.
* @param {String} str the string to use.
* @param {Array|ArrayBuffer|Uint8Array|Buffer} array the array to fill in (will be mutated).
* @return {Array|ArrayBuffer|Uint8Array|Buffer} the updated array.
*/
function stringToArrayLike(str, array) {
for (var i = 0; i < str.length; ++i) {
array[i] = str.charCodeAt(i) & 0xFF;
}
return array;
}
/**
* Transform an array-like object to a string.
* @param {Array|ArrayBuffer|Uint8Array|Buffer} array the array to transform.
* @return {String} the result.
*/
function arrayLikeToString(array) {
// Performances notes :
// --------------------
// String.fromCharCode.apply(null, array) is the fastest, see
// see http://jsperf.com/converting-a-uint8array-to-a-string/2
// but the stack is limited (and we can get huge arrays !).
//
// result += String.fromCharCode(array[i]); generate too many strings !
//
// This code is inspired by http://jsperf.com/arraybuffer-to-string-apply-performance/2
var chunk = 65536;
var result = [],
len = array.length,
type = exports.getTypeOf(array),
k = 0,
canUseApply = true;
try {
switch(type) {
case "uint8array":
String.fromCharCode.apply(null, new Uint8Array(0));
break;
case "nodebuffer":
String.fromCharCode.apply(null, nodeBuffer(0));
break;
}
} catch(e) {
canUseApply = false;
}
// no apply : slow and painful algorithm
// default browser on android 4.*
if (!canUseApply) {
var resultStr = "";
for(var i = 0; i < array.length;i++) {
resultStr += String.fromCharCode(array[i]);
}
return resultStr;
}
while (k < len && chunk > 1) {
try {
if (type === "array" || type === "nodebuffer") {
result.push(String.fromCharCode.apply(null, array.slice(k, Math.min(k + chunk, len))));
}
else {
result.push(String.fromCharCode.apply(null, array.subarray(k, Math.min(k + chunk, len))));
}
k += chunk;
}
catch (e) {
chunk = Math.floor(chunk / 2);
}
}
return result.join("");
}
exports.applyFromCharCode = arrayLikeToString;
/**
* Copy the data from an array-like to an other array-like.
* @param {Array|ArrayBuffer|Uint8Array|Buffer} arrayFrom the origin array.
* @param {Array|ArrayBuffer|Uint8Array|Buffer} arrayTo the destination array which will be mutated.
* @return {Array|ArrayBuffer|Uint8Array|Buffer} the updated destination array.
*/
function arrayLikeToArrayLike(arrayFrom, arrayTo) {
for (var i = 0; i < arrayFrom.length; i++) {
arrayTo[i] = arrayFrom[i];
}
return arrayTo;
}
// a matrix containing functions to transform everything into everything.
var transform = {};
// string to ?
transform["string"] = {
"string": identity,
"array": function(input) {
return stringToArrayLike(input, new Array(input.length));
},
"arraybuffer": function(input) {
return transform["string"]["uint8array"](input).buffer;
},
"uint8array": function(input) {
return stringToArrayLike(input, new Uint8Array(input.length));
},
"nodebuffer": function(input) {
return stringToArrayLike(input, nodeBuffer(input.length));
}
};
// array to ?
transform["array"] = {
"string": arrayLikeToString,
"array": identity,
"arraybuffer": function(input) {
return (new Uint8Array(input)).buffer;
},
"uint8array": function(input) {
return new Uint8Array(input);
},
"nodebuffer": function(input) {
return nodeBuffer(input);
}
};
// arraybuffer to ?
transform["arraybuffer"] = {
"string": function(input) {
return arrayLikeToString(new Uint8Array(input));
},
"array": function(input) {
return arrayLikeToArrayLike(new Uint8Array(input), new Array(input.byteLength));
},
"arraybuffer": identity,
"uint8array": function(input) {
return new Uint8Array(input);
},
"nodebuffer": function(input) {
return nodeBuffer(new Uint8Array(input));
}
};
// uint8array to ?
transform["uint8array"] = {
"string": arrayLikeToString,
"array": function(input) {
return arrayLikeToArrayLike(input, new Array(input.length));
},
"arraybuffer": function(input) {
return input.buffer;
},
"uint8array": identity,
"nodebuffer": function(input) {
return nodeBuffer(input);
}
};
// nodebuffer to ?
transform["nodebuffer"] = {
"string": arrayLikeToString,
"array": function(input) {
return arrayLikeToArrayLike(input, new Array(input.length));
},
"arraybuffer": function(input) {
return transform["nodebuffer"]["uint8array"](input).buffer;
},
"uint8array": function(input) {
return arrayLikeToArrayLike(input, new Uint8Array(input.length));
},
"nodebuffer": identity
};
/**
* Transform an input into any type.
* The supported output type are : string, array, uint8array, arraybuffer, nodebuffer.
* If no output type is specified, the unmodified input will be returned.
* @param {String} outputType the output type.
* @param {String|Array|ArrayBuffer|Uint8Array|Buffer} input the input to convert.
* @throws {Error} an Error if the browser doesn't support the requested output type.
*/
exports.transformTo = function(outputType, input) {
if (!input) {
// undefined, null, etc
// an empty string won't harm.
input = "";
}
if (!outputType) {
return input;
}
exports.checkSupport(outputType);
var inputType = exports.getTypeOf(input);
var result = transform[inputType][outputType](input);
return result;
};
/**
* Return the type of the input.
* The type will be in a format valid for JSZip.utils.transformTo : string, array, uint8array, arraybuffer.
* @param {Object} input the input to identify.
* @return {String} the (lowercase) type of the input.
*/
exports.getTypeOf = function(input) {
if (typeof input === "string") {
return "string";
}
if (Object.prototype.toString.call(input) === "[object Array]") {
return "array";
}
if (support.nodebuffer && nodeBuffer.test(input)) {
return "nodebuffer";
}
if (support.uint8array && input instanceof Uint8Array) {
return "uint8array";
}
if (support.arraybuffer && input instanceof ArrayBuffer) {
return "arraybuffer";
}
};
/**
* Throw an exception if the type is not supported.
* @param {String} type the type to check.
* @throws {Error} an Error if the browser doesn't support the requested type.
*/
exports.checkSupport = function(type) {
var supported = support[type.toLowerCase()];
if (!supported) {
throw new Error(type + " is not supported by this browser");
}
};
exports.MAX_VALUE_16BITS = 65535;
exports.MAX_VALUE_32BITS = -1; // well, "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF" is parsed as -1
/**
* Prettify a string read as binary.
* @param {string} str the string to prettify.
* @return {string} a pretty string.
*/
exports.pretty = function(str) {
var res = '',
code, i;
for (i = 0; i < (str || "").length; i++) {
code = str.charCodeAt(i);
res += '\\x' + (code < 16 ? "0" : "") + code.toString(16).toUpperCase();
}
return res;
};
/**
* Find a compression registered in JSZip.
* @param {string} compressionMethod the method magic to find.
* @return {Object|null} the JSZip compression object, null if none found.
*/
exports.findCompression = function(compressionMethod) {
for (var method in compressions) {
if (!compressions.hasOwnProperty(method)) {
continue;
}
if (compressions[method].magic === compressionMethod) {
return compressions[method];
}
}
return null;
};
/**
* Cross-window, cross-Node-context regular expression detection
* @param {Object} object Anything
* @return {Boolean} true if the object is a regular expression,
* false otherwise
*/
exports.isRegExp = function (object) {
return Object.prototype.toString.call(object) === "[object RegExp]";
};