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- var Utils = require("./util"),
- Headers = require("./headers"),
- Constants = Utils.Constants,
- Methods = require("./methods");
- module.exports = function (/*Buffer*/input) {
- var _entryHeader = new Headers.EntryHeader(),
- _entryName = Buffer.alloc(0),
- _comment = Buffer.alloc(0),
- _isDirectory = false,
- uncompressedData = null,
- _extra = Buffer.alloc(0);
- function getCompressedDataFromZip() {
- if (!input || !Buffer.isBuffer(input)) {
- return Buffer.alloc(0);
- }
- _entryHeader.loadDataHeaderFromBinary(input);
- return input.slice(_entryHeader.realDataOffset, _entryHeader.realDataOffset + _entryHeader.compressedSize)
- }
- function crc32OK(data) {
- // if bit 3 (0x08) of the general-purpose flags field is set, then the CRC-32 and file sizes are not known when the header is written
- if ((_entryHeader.flags & 0x8) !== 0x8) {
- if (Utils.crc32(data) !== _entryHeader.crc) {
- return false;
- }
- } else {
- // @TODO: load and check data descriptor header
- // The fields in the local header are filled with zero, and the CRC-32 and size are appended in a 12-byte structure
- // (optionally preceded by a 4-byte signature) immediately after the compressed data:
- }
- return true;
- }
- function decompress(/*Boolean*/async, /*Function*/callback, /*String*/pass) {
- if(typeof callback === 'undefined' && typeof async === 'string') {
- pass=async;
- async=void 0;
- }
- if (_isDirectory) {
- if (async && callback) {
- callback(Buffer.alloc(0), Utils.Errors.DIRECTORY_CONTENT_ERROR); //si added error.
- }
- return Buffer.alloc(0);
- }
- var compressedData = getCompressedDataFromZip();
-
- if (compressedData.length === 0) {
- if (async && callback) callback(compressedData, Utils.Errors.NO_DATA);//si added error.
- return compressedData;
- }
- var data = Buffer.alloc(_entryHeader.size);
- switch (_entryHeader.method) {
- case Utils.Constants.STORED:
- compressedData.copy(data);
- if (!crc32OK(data)) {
- if (async && callback) callback(data, Utils.Errors.BAD_CRC);//si added error
- return Utils.Errors.BAD_CRC;
- } else {//si added otherwise did not seem to return data.
- if (async && callback) callback(data);
- return data;
- }
- case Utils.Constants.DEFLATED:
- var inflater = new Methods.Inflater(compressedData);
- if (!async) {
- inflater.inflate(data);
- if (!crc32OK(data)) {
- console.warn(Utils.Errors.BAD_CRC + " " + _entryName.toString())
- }
- return data;
- } else {
- inflater.inflateAsync(function(result) {
- result.copy(data, 0);
- if (!crc32OK(data)) {
- if (callback) callback(data, Utils.Errors.BAD_CRC); //si added error
- } else { //si added otherwise did not seem to return data.
- if (callback) callback(data);
- }
- })
- }
- break;
- default:
- if (async && callback) callback(Buffer.alloc(0), Utils.Errors.UNKNOWN_METHOD);
- return Utils.Errors.UNKNOWN_METHOD;
- }
- }
- function compress(/*Boolean*/async, /*Function*/callback) {
- if ((!uncompressedData || !uncompressedData.length) && Buffer.isBuffer(input)) {
- // no data set or the data wasn't changed to require recompression
- if (async && callback) callback(getCompressedDataFromZip());
- return getCompressedDataFromZip();
- }
- if (uncompressedData.length && !_isDirectory) {
- var compressedData;
- // Local file header
- switch (_entryHeader.method) {
- case Utils.Constants.STORED:
- _entryHeader.compressedSize = _entryHeader.size;
- compressedData = Buffer.alloc(uncompressedData.length);
- uncompressedData.copy(compressedData);
- if (async && callback) callback(compressedData);
- return compressedData;
- default:
- case Utils.Constants.DEFLATED:
- var deflater = new Methods.Deflater(uncompressedData);
- if (!async) {
- var deflated = deflater.deflate();
- _entryHeader.compressedSize = deflated.length;
- return deflated;
- } else {
- deflater.deflateAsync(function(data) {
- compressedData = Buffer.alloc(data.length);
- _entryHeader.compressedSize = data.length;
- data.copy(compressedData);
- callback && callback(compressedData);
- })
- }
- deflater = null;
- break;
- }
- } else {
- if (async && callback) {
- callback(Buffer.alloc(0));
- } else {
- return Buffer.alloc(0);
- }
- }
- }
- function readUInt64LE(buffer, offset) {
- return (buffer.readUInt32LE(offset + 4) << 4) + buffer.readUInt32LE(offset);
- }
- function parseExtra(data) {
- var offset = 0;
- var signature, size, part;
- while(offset<data.length) {
- signature = data.readUInt16LE(offset);
- offset += 2;
- size = data.readUInt16LE(offset);
- offset += 2;
- part = data.slice(offset, offset+size);
- offset += size;
- if(Constants.ID_ZIP64 === signature) {
- parseZip64ExtendedInformation(part);
- }
- }
- }
- //Override header field values with values from the ZIP64 extra field
- function parseZip64ExtendedInformation(data) {
- var size, compressedSize, offset, diskNumStart;
- if(data.length >= Constants.EF_ZIP64_SCOMP) {
- size = readUInt64LE(data, Constants.EF_ZIP64_SUNCOMP);
- if(_entryHeader.size === Constants.EF_ZIP64_OR_32) {
- _entryHeader.size = size;
- }
- }
- if(data.length >= Constants.EF_ZIP64_RHO) {
- compressedSize = readUInt64LE(data, Constants.EF_ZIP64_SCOMP);
- if(_entryHeader.compressedSize === Constants.EF_ZIP64_OR_32) {
- _entryHeader.compressedSize = compressedSize;
- }
- }
- if(data.length >= Constants.EF_ZIP64_DSN) {
- offset = readUInt64LE(data, Constants.EF_ZIP64_RHO);
- if(_entryHeader.offset === Constants.EF_ZIP64_OR_32) {
- _entryHeader.offset = offset;
- }
- }
- if(data.length >= Constants.EF_ZIP64_DSN+4) {
- diskNumStart = data.readUInt32LE(Constants.EF_ZIP64_DSN);
- if(_entryHeader.diskNumStart === Constants.EF_ZIP64_OR_16) {
- _entryHeader.diskNumStart = diskNumStart;
- }
- }
- }
- return {
- get entryName () { return _entryName.toString(); },
- get rawEntryName() { return _entryName; },
- set entryName (val) {
- _entryName = Utils.toBuffer(val);
- var lastChar = _entryName[_entryName.length - 1];
- _isDirectory = (lastChar === 47) || (lastChar === 92);
- _entryHeader.fileNameLength = _entryName.length;
- },
- get extra () { return _extra; },
- set extra (val) {
- _extra = val;
- _entryHeader.extraLength = val.length;
- parseExtra(val);
- },
- get comment () { return _comment.toString(); },
- set comment (val) {
- _comment = Utils.toBuffer(val);
- _entryHeader.commentLength = _comment.length;
- },
- get name () { var n = _entryName.toString(); return _isDirectory ? n.substr(n.length - 1).split("/").pop() : n.split("/").pop(); },
- get isDirectory () { return _isDirectory },
- getCompressedData : function() {
- return compress(false, null)
- },
- getCompressedDataAsync : function(/*Function*/callback) {
- compress(true, callback)
- },
- setData : function(value) {
- uncompressedData = Utils.toBuffer(value);
- if (!_isDirectory && uncompressedData.length) {
- _entryHeader.size = uncompressedData.length;
- _entryHeader.method = Utils.Constants.STORED;
- _entryHeader.crc = Utils.crc32(value);
- _entryHeader.changed = true;
- } else { // folders and blank files should be stored
- _entryHeader.method = Utils.Constants.STORED;
- }
- },
- getData : function(pass) {
- if (_entryHeader.changed) {
- return uncompressedData;
- } else {
- return decompress(false, null, pass);
- }
- },
- getDataAsync : function(/*Function*/callback, pass) {
- if (_entryHeader.changed) {
- callback(uncompressedData)
- } else {
- decompress(true, callback, pass)
- }
- },
- set attr(attr) { _entryHeader.attr = attr; },
- get attr() { return _entryHeader.attr; },
- set header(/*Buffer*/data) {
- _entryHeader.loadFromBinary(data);
- },
- get header() {
- return _entryHeader;
- },
- packHeader : function() {
- var header = _entryHeader.entryHeaderToBinary();
- // add
- _entryName.copy(header, Utils.Constants.CENHDR);
- if (_entryHeader.extraLength) {
- _extra.copy(header, Utils.Constants.CENHDR + _entryName.length)
- }
- if (_entryHeader.commentLength) {
- _comment.copy(header, Utils.Constants.CENHDR + _entryName.length + _entryHeader.extraLength, _comment.length);
- }
- return header;
- },
- toString : function() {
- return '{\n' +
- '\t"entryName" : "' + _entryName.toString() + "\",\n" +
- '\t"name" : "' + (_isDirectory ? _entryName.toString().replace(/\/$/, '').split("/").pop() : _entryName.toString().split("/").pop()) + "\",\n" +
- '\t"comment" : "' + _comment.toString() + "\",\n" +
- '\t"isDirectory" : ' + _isDirectory + ",\n" +
- '\t"header" : ' + _entryHeader.toString().replace(/\t/mg, "\t\t").replace(/}/mg, "\t}") + ",\n" +
- '\t"compressedData" : <' + (input && input.length + " bytes buffer" || "null") + ">\n" +
- '\t"data" : <' + (uncompressedData && uncompressedData.length + " bytes buffer" || "null") + ">\n" +
- '}';
- }
- }
- };
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