1 /**
  2  * Copyright (C) 2012 KO GmbH <copyright@kogmbh.com>
  3  *
  4  * @licstart
  5  * This file is part of WebODF.
  6  *
  7  * WebODF is free software: you can redistribute it and/or modify it
  8  * under the terms of the GNU Affero General Public License (GNU AGPL)
  9  * as published by the Free Software Foundation, either version 3 of
 10  * the License, or (at your option) any later version.
 11  *
 12  * WebODF is distributed in the hope that it will be useful, but
 13  * WITHOUT ANY WARRANTY; without even the implied warranty of
 14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15  * GNU Affero General Public License for more details.
 16  *
 17  * You should have received a copy of the GNU Affero General Public License
 18  * along with WebODF.  If not, see <http://www.gnu.org/licenses/>.
 19  * @licend
 20  *
 21  * @source: http://www.webodf.org/
 22  * @source: https://github.com/kogmbh/WebODF/
 23  */
 24 
 25 /*global runtime, core, DOMParser*/
 26 /*jslint bitwise: true*/
 27 
 28 /**
 29  * @constructor
 30  * @param {!string} url path to zip file, should be readable by the runtime
 31  * @param {?function(?string, !core.Zip):undefined} entriesReadCallback callback
 32  *        indicating the zip
 33  *        has loaded this list of entries, the arguments are a string that
 34  *        indicates error if present and the created object
 35  */
 36 core.Zip = function Zip(url, entriesReadCallback) {
 37     "use strict";
 38     var /**@type{Array.<!ZipEntry>}*/
 39         entries,
 40         /**@type{?Uint8Array}*/
 41         fileData,
 42         /**@type{number}*/
 43         filesize,
 44         /**@type{number}*/
 45         nEntries,
 46         /**@type{!function(!Uint8Array,number):!Uint8Array}*/
 47         inflate = core.RawInflate.inflate,
 48         /**@type{!core.Zip}*/
 49         zip = this,
 50         base64 = new core.Base64();
 51 
 52     /**
 53      * @param {!number} offset
 54      * @param {!number} length
 55      * @param {!function(?string,?Uint8Array):undefined} callback
 56      * @return {undefined}
 57      */
 58     function read(offset, length, callback) {
 59         if (fileData) {
 60             callback(null, fileData.subarray(offset, offset + length));
 61         } else {
 62             callback("File data not loaded", null);
 63         }
 64     }
 65 
 66     /**
 67      * @param {!Uint8Array} data
 68      * @return {!number}
 69      */
 70     function crc32(data) {
 71         // Calculate the crc32 polynomial of a string
 72         //
 73         // version: 1009.2513
 74         // discuss at: http:\/\/phpjs.org\/functions\/crc32
 75         // +   original by: Webtoolkit.info (http:\/\/www.webtoolkit.info\/)
 76         // +   improved by: T0bsn
 77         // -    depends on: utf8_encode
 78         // *     example 1: crc32('Kevin van Zonneveld');
 79         // *     returns 1: 1249991249
 80         var /**@const
 81                @type{!Array.<!number>}*/
 82             table = [0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F, 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433, 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01, 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F, 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD, 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79, 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D, 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713, 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777, 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF, 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D],
 83             /**@type{!number}*/
 84             crc = 0,
 85             /**@type{!number}*/
 86             i,
 87             /**@const@type{!number}*/
 88             iTop = data.length,
 89             /**@type{!number}*/
 90             x = 0,
 91             /**@type{!number}*/
 92             y = 0;
 93         crc = crc ^ (-1);
 94         for (i = 0; i < iTop; i += 1) {
 95             y = (crc ^ data[i]) & 0xFF;
 96             x = table[y];
 97             crc = (crc >>> 8) ^ x;
 98         }
 99         return crc ^ (-1);
100     }
101 
102     /**
103      * @param {!number} dostime
104      * @return {!Date}
105      */
106     function dosTime2Date(dostime) {
107         var /**@const@type{!number}*/
108             year = ((dostime >> 25) & 0x7f) + 1980,
109             /**@const@type{!number}*/
110             month = ((dostime >> 21) & 0x0f) - 1,
111             /**@const@type{!number}*/
112             mday = (dostime >> 16) & 0x1f,
113             /**@const@type{!number}*/
114             hour = (dostime >> 11) & 0x0f,
115             /**@const@type{!number}*/
116             min = (dostime >> 5) & 0x3f,
117             /**@const@type{!number}*/
118             sec = (dostime & 0x1f) << 1,
119             /**@const@type{!Date}*/
120             d = new Date(year, month, mday, hour, min, sec);
121         return d;
122     }
123     /**
124      * @param {!Date} date
125      * @return {!number}
126      */
127     function date2DosTime(date) {
128         var /**@const@type{!number}*/ y = date.getFullYear();
129         return y < 1980 ? 0 :
130                 ((y - 1980) << 25) | ((date.getMonth() + 1) << 21) |
131                 (date.getDate() << 16) | (date.getHours() << 11) |
132                 (date.getMinutes() << 5) | (date.getSeconds() >> 1);
133     }
134     /**
135      * Create a new ZipEntry.
136      * If the stream is not provided, the object should be initialized
137      * with ZipEntry.set()
138      * @constructor
139      * @param {!string} url
140      * @param {!core.ByteArray=} stream
141      */
142     function ZipEntry(url, stream) {
143         var /**@const
144                @type{!number}*/
145             sig,
146             /**@const
147                @type{!number}*/
148             namelen,
149             /**@const
150                @type{!number}*/
151             extralen,
152             /**@const
153                @type{!number}*/
154             commentlen,
155             /**@const
156                @type{!number}*/
157             compressionMethod,
158             /**@const
159                @type{!number}*/
160             compressedSize,
161             /**@const
162                @type{!number}*/
163             uncompressedSize,
164             /**@const
165                @type{!number}*/
166             offset,
167             /**@const
168                @type{!ZipEntry}*/
169             entry = this;
170 
171         /**
172          * @param {!Uint8Array} data
173          * @param {!function(?string, ?Uint8Array)} callback
174          * @return {undefined}
175          */
176         function handleEntryData(data, callback) {
177             var /**@const
178                    @type{!core.ByteArray}*/
179                 estream = new core.ByteArray(data),
180                 /**@const
181                    @type{!number}*/
182                 esig = estream.readUInt32LE(),
183                 /**@const
184                    @type{!number}*/
185                 filenamelen,
186                 /**@const
187                    @type{!number}*/
188                 eextralen;
189             if (esig !== 0x04034b50) {
190                 callback('File entry signature is wrong.' + esig.toString() +
191                         ' ' + data.length.toString(), null);
192                 return;
193             }
194             estream.pos += 22;
195             filenamelen = estream.readUInt16LE();
196             eextralen = estream.readUInt16LE();
197             estream.pos += filenamelen + eextralen;
198             if (compressionMethod) {
199                 data = data.subarray(estream.pos, estream.pos + compressedSize);
200                 if (compressedSize !== data.length) {
201                     callback("The amount of compressed bytes read was " +
202                         data.length.toString() + " instead of " +
203                         compressedSize.toString() + " for " + entry.filename +
204                         " in " + url + ".", null);
205                     return;
206                 }
207                 data = inflate(data, uncompressedSize);
208             } else {
209                 data = data.subarray(estream.pos, estream.pos + uncompressedSize);
210             }
211             if (uncompressedSize !== data.length) {
212                 callback("The amount of bytes read was " +
213                         data.length.toString() +
214                         " instead of " + uncompressedSize.toString() + " for " +
215                         entry.filename + " in " + url + ".", null);
216                 return;
217             }
218 /*
219  * This check is disabled for performance reasons
220             if (crc !== crc32(data)) {
221                 runtime.log("Warning: CRC32 for " + entry.filename +
222                     " is wrong.");
223             }
224 */
225             entry.data = data;
226             callback(null, data);
227         }
228         /**
229          * @param {!function(?string, ?Uint8Array)} callback
230          * @return {undefined}
231          */
232         function load(callback) {
233             // if data has already been downloaded, use that
234             if (entry.data !== null) {
235                 callback(null, entry.data);
236                 return;
237             }
238             // the 256 at the end is security for when local extra field is
239             // larger
240             var /**@type{!number}*/ size
241                 = compressedSize + 34 + namelen + extralen + 256;
242             if (size + offset > filesize) {
243                 size = filesize - offset;
244             }
245             read(offset, size, function (err, data) {
246                 if (err || data === null) {
247                     callback(err, data);
248                 } else {
249                     handleEntryData(data, callback);
250                 }
251             });
252         }
253         this.load = load;
254         /**
255          * @param {!string} filename
256          * @param {!Uint8Array} data
257          * @param {!boolean} compressed
258          * @param {!Date} date
259          * @return {undefined}
260          */
261         function set(filename, data, compressed, date) {
262             entry.filename = filename;
263             entry.data = data;
264             entry.compressed = compressed;
265             entry.date = date;
266         }
267         this.set = set;
268         /**
269          * @type {?string}
270          */
271         this.error = null;
272 
273         if (!stream) {
274             return;
275         }
276         sig = stream.readUInt32LE();
277 
278         if (sig !== 0x02014b50) {
279             this.error =
280                 "Central directory entry has wrong signature at position " +
281                 (stream.pos - 4).toString() + ' for file "' + url + '": ' +
282                 stream.data.length.toString();
283             return;
284         }
285         // stream should be positioned at the start of the CDS entry for the
286         // file
287         stream.pos += 6;
288         compressionMethod = stream.readUInt16LE();
289         this.date = dosTime2Date(stream.readUInt32LE());
290         stream.readUInt32LE();
291         compressedSize = stream.readUInt32LE();
292         uncompressedSize = stream.readUInt32LE();
293         namelen = stream.readUInt16LE();
294         extralen = stream.readUInt16LE();
295         commentlen = stream.readUInt16LE();
296         stream.pos += 8;
297         offset = stream.readUInt32LE();
298         this.filename = runtime.byteArrayToString(
299             stream.data.subarray(stream.pos, stream.pos + namelen),
300             "utf8"
301         );
302         /**@type{?Uint8Array}*/
303         this.data = null;
304         stream.pos += namelen + extralen + commentlen;
305     }
306     /**
307      * @param {!Uint8Array} data
308      * @param {!function(?string, !core.Zip)} callback
309      * @return {undefined}
310      */
311     function handleCentralDirectory(data, callback) {
312         // parse the central directory
313         var stream = new core.ByteArray(data), i, e;
314         entries = [];
315         for (i = 0; i < nEntries; i += 1) {
316             e = new ZipEntry(url, stream);
317             if (e.error) {
318                 callback(e.error, zip);
319                 return;
320             }
321             entries[entries.length] = e;
322         }
323         // report that entries are listed and no error occured
324         callback(null, zip);
325     }
326     /**
327      * @param {!Uint8Array} data
328      * @param {!function(?string, !core.Zip)} callback
329      * @return {undefined}
330      */
331     function handleCentralDirectoryEnd(data, callback) {
332         if (data.length !== 22) {
333             callback("Central directory length should be 22.", zip);
334             return;
335         }
336         var stream = new core.ByteArray(data), sig, disk, cddisk, diskNEntries,
337             cdsSize, cdsOffset;
338         sig = stream.readUInt32LE();
339         if (sig !== 0x06054b50) {
340             callback('Central directory signature is wrong: ' + sig.toString(),
341                     zip);
342             return;
343         }
344         disk = stream.readUInt16LE();
345         if (disk !== 0) {
346             callback('Zip files with non-zero disk numbers are not supported.',
347                     zip);
348             return;
349         }
350         cddisk = stream.readUInt16LE();
351         if (cddisk !== 0) {
352             callback('Zip files with non-zero disk numbers are not supported.',
353                     zip);
354             return;
355         }
356         diskNEntries = stream.readUInt16LE();
357         nEntries = stream.readUInt16LE();
358         if (diskNEntries !== nEntries) {
359             callback('Number of entries is inconsistent.', zip);
360             return;
361         }
362         cdsSize = stream.readUInt32LE();
363         cdsOffset = stream.readUInt16LE();
364         cdsOffset = filesize - 22 - cdsSize;
365 
366         // for some reason cdsOffset is not always equal to offset calculated
367         // from the central directory size. The latter is reliable.
368         read(cdsOffset, filesize - cdsOffset,
369             function (err, data) {
370                 if (err || data === null) {
371                     callback(err, zip);
372                 } else {
373                     handleCentralDirectory(data, callback);
374                 }
375             });
376     }
377     /**
378      * @param {!string} filename
379      * @param {!function(?string, ?Uint8Array)} callback receiving err and data
380      * @return {undefined}
381      */
382     function load(filename, callback) {
383         var entry = null,
384             e,
385             i;
386         for (i = 0; i < entries.length; i += 1) {
387             e = entries[i];
388             if (e.filename === filename) {
389                 entry = e;
390                 break;
391             }
392         }
393         if (entry) {
394             if (entry.data) {
395                 callback(null, entry.data);
396             } else {
397                 entry.load(callback);
398             }
399         } else {
400             callback(filename + " not found.", null);
401         }
402     }
403     /**
404      * @param {!string} filename
405      * @param {!function(?string, ?string):undefined} callback receiving err and data
406      * @return {undefined}
407      */
408     function loadAsString(filename, callback) {
409         // the javascript implementation simply reads the file and converts to
410         // string
411         load(filename, function (err, data) {
412             if (err || data === null) {
413                 return callback(err, null);
414             }
415             var d = runtime.byteArrayToString(data, "utf8");
416             callback(null, d);
417         });
418     }
419     /**
420      * @param {!string} filename
421      * @param {!{rootElementReady: function(?string, ?string=, boolean=):undefined}} handler
422      * @return {undefined}
423      */
424     function loadContentXmlAsFragments(filename, handler) {
425         // the javascript implementation simply reads the file
426         zip.loadAsString(filename, function (err, data) {
427             if (err) {
428                 return handler.rootElementReady(err);
429             }
430             handler.rootElementReady(null, data, true);
431         });
432     }
433     /**
434      * @param {!string} filename
435      * @param {!string} mimetype
436      * @param {!function(?string,?string):undefined} callback
437      */
438     function loadAsDataURL(filename, mimetype, callback) {
439         load(filename, function (err, data) {
440             if (err || !data) {
441                 return callback(err, null);
442             }
443             var /**@const@type{!Uint8Array}*/p = data,
444                 chunksize = 45000, // must be multiple of 3 and less than 50000
445                 i = 0,
446                 dataurl;
447             if (!mimetype) {
448                 if (p[1] === 0x50 && p[2] === 0x4E && p[3] === 0x47) {
449                     mimetype = "image/png";
450                 } else if (p[0] === 0xFF && p[1] === 0xD8 && p[2] === 0xFF) {
451                     mimetype = "image/jpeg";
452                 } else if (p[0] === 0x47 && p[1] === 0x49 && p[2] === 0x46) {
453                     mimetype = "image/gif";
454                 } else {
455                     mimetype = "";
456                 }
457             }
458             dataurl = 'data:' + mimetype + ';base64,';
459             // to avoid exceptions, base64 encoding is done in chunks
460             // it would make sense to move this to base64.toBase64
461             while (i < data.length) {
462                 dataurl += base64.convertUTF8ArrayToBase64(
463                     p.subarray(i, Math.min(i + chunksize, p.length))
464                 );
465                 i += chunksize;
466             }
467             callback(null, dataurl);
468         });
469     }
470     /**
471      * @param {!string} filename
472      * @param {function(?string,?Document):undefined} callback
473      * @return {undefined}
474      */
475     function loadAsDOM(filename, callback) {
476         zip.loadAsString(filename, function (err, xmldata) {
477             if (err || xmldata === null) {
478                 callback(err, null);
479                 return;
480             }
481             var parser = new DOMParser(),
482                 dom = parser.parseFromString(xmldata, "text/xml");
483             callback(null, dom);
484         });
485     }
486     /**
487      * Add or replace an entry to the zip file.
488      * This data is not stored to disk yet, and therefore, no callback is
489      * necessary.
490      * @param {!string} filename
491      * @param {!Uint8Array} data
492      * @param {!boolean} compressed
493      * @param {!Date} date
494      * @return {undefined}
495      */
496     function save(filename, data, compressed, date) {
497         var i,
498             entry;
499         for (i = 0; i < entries.length; i += 1) {
500             entry = entries[i];
501             if (entry.filename === filename) {
502                 entry.set(filename, data, compressed, date);
503                 return;
504             }
505         }
506         entry = new ZipEntry(url);
507         entry.set(filename, data, compressed, date);
508         entries.push(entry);
509     }
510     /**
511      * Removes entry from the zip.
512      * @param {!string} filename
513      * @return {!boolean} return false if entry is not found; otherwise true.
514      */
515     function remove(filename) {
516         var i, entry;
517         for (i = 0; i < entries.length; i += 1) {
518             entry = entries[i];
519             if (entry.filename === filename) {
520                 entries.splice(i, 1);
521                 return true;
522             }
523         }
524         return false;
525     }
526     /**
527      * @param {!ZipEntry} entry
528      * @return {!core.ByteArrayWriter}
529      */
530     function writeEntry(entry) {
531         // each entry is currently stored uncompressed
532         var data = new core.ByteArrayWriter("utf8"),
533             length = 0;
534         data.appendArray([0x50, 0x4B, 0x03, 0x04, 0x14, 0, 0, 0, 0, 0]);
535         if (entry.data) {
536             length = entry.data.length;
537         }
538         data.appendUInt32LE(date2DosTime(entry.date));
539         data.appendUInt32LE(entry.data ? crc32(entry.data) : 0);
540         data.appendUInt32LE(length); // compressedSize
541         data.appendUInt32LE(length); // uncompressedSize
542         data.appendUInt16LE(entry.filename.length); // namelen
543         data.appendUInt16LE(0); // extralen
544         data.appendString(entry.filename);
545         if (entry.data) {
546             data.appendByteArray(entry.data);
547         }
548         return data;
549     }
550     /**
551      * @param {!ZipEntry} entry
552      * @param {!number} offset
553      * @return {!core.ByteArrayWriter}
554      */
555     function writeCODEntry(entry, offset) {
556         // each entry is currently stored uncompressed
557         var data = new core.ByteArrayWriter("utf8"),
558             length = 0;
559         data.appendArray([0x50, 0x4B, 0x01, 0x02, 0x14, 0x00, 0x14, 0x00,
560                 0, 0, 0, 0]);
561         if (entry.data) {
562             length = entry.data.length;
563         }
564         data.appendUInt32LE(date2DosTime(entry.date));
565         data.appendUInt32LE(entry.data ? crc32(entry.data) : 0);
566         data.appendUInt32LE(length); // compressedSize
567         data.appendUInt32LE(length); // uncompressedSize
568         data.appendUInt16LE(entry.filename.length); // namelen
569         // extralen, commalen, diskno, file attributes
570         data.appendArray([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]);
571         data.appendUInt32LE(offset);
572         data.appendString(entry.filename);
573         return data;
574     }
575     /**
576      * @param {!number} position
577      * @param {!function(?string):undefined} callback
578      * @return {undefined}
579      */
580     function loadAllEntries(position, callback) {
581         if (position === entries.length) {
582             callback(null);
583             return;
584         }
585         var entry = entries[position];
586         if (entry.data !== null) {
587             loadAllEntries(position + 1, callback);
588             return;
589         }
590         entry.load(function (err) {
591             if (err) {
592                 callback(err);
593                 return;
594             }
595             loadAllEntries(position + 1, callback);
596         });
597     }
598     /**
599      * Create a bytearray from the zipfile.
600      * @param {!function(!Uint8Array):undefined} successCallback receiving zip as bytearray
601      * @param {!function(?string):undefined} errorCallback receiving possible err
602      * @return {undefined}
603      */
604     function createByteArray(successCallback, errorCallback) {
605         // make sure all data is in memory, for each entry that has data
606         // undefined, try to load the entry
607         loadAllEntries(0, function (err) {
608             if (err) {
609                 errorCallback(err);
610                 return;
611             }
612             var i, e, codoffset, codsize,
613                 data = new core.ByteArrayWriter("utf8"),
614                 offsets = [0];
615             // write entries
616             for (i = 0; i < entries.length; i += 1) {
617                 data.appendByteArrayWriter(writeEntry(entries[i]));
618                 offsets.push(data.getLength());
619             }
620             // write central directory
621             codoffset = data.getLength();
622             for (i = 0; i < entries.length; i += 1) {
623                 e = entries[i];
624                 data.appendByteArrayWriter(writeCODEntry(e, offsets[i]));
625             }
626             codsize = data.getLength() - codoffset;
627             data.appendArray([0x50, 0x4B, 0x05, 0x06, 0, 0, 0, 0]);
628             data.appendUInt16LE(entries.length);
629             data.appendUInt16LE(entries.length);
630             data.appendUInt32LE(codsize);
631             data.appendUInt32LE(codoffset);
632             data.appendArray([0, 0]);
633 
634             successCallback(data.getByteArray());
635         });
636     }
637     /**
638      * Write the zipfile to the given path.
639      * @param {!string} newurl
640      * @param {!function(?string):undefined} callback receiving possible err
641      * @return {undefined}
642      */
643     function writeAs(newurl, callback) {
644         // make sure all data is in memory, for each entry that has data
645         // undefined, try to load the entry
646         createByteArray(function (data) {
647             runtime.writeFile(newurl, data, function (err) {
648                 if (!err) {
649                     fileData = data;
650                     filesize = fileData.length;
651                 }
652                 callback(err);
653             });
654         }, callback);
655     }
656     /**
657      * Write the zipfile to the given path.
658      * @param {!function(?string):undefined} callback receiving possible err
659      * @return {undefined}
660      */
661     function write(callback) {
662         writeAs(url, callback);
663     }
664     this.load = load;
665     this.save = save;
666     this.remove = remove;
667     this.write = write;
668     this.writeAs = writeAs;
669     this.createByteArray = createByteArray;
670     // a special function that makes faster odf loading possible
671     this.loadContentXmlAsFragments = loadContentXmlAsFragments;
672     this.loadAsString = loadAsString;
673     this.loadAsDOM = loadAsDOM;
674     this.loadAsDataURL = loadAsDataURL;
675     this.getEntries = function () {
676         return entries.slice();
677     };
678 
679     // determine the file size
680     filesize = -1;
681     // if no callback is defined, this is a new file
682     if (entriesReadCallback === null) {
683         entries = [];
684         return;
685     }
686     runtime.readFile(url, "binary", function (err, result) {
687         if (typeof result === "string") {
688             err = "file was read as a string. Should be Uint8Array.";
689         }
690         if (err || !result || result.length === 0) {
691             entriesReadCallback("File '" + url + "' cannot be read. Err: " + (err || "[none]"), zip);
692         } else {
693             fileData = /**@type{!Uint8Array}*/(result);
694             filesize = fileData.length;
695             read(filesize - 22, 22, function (err, data) {
696                 // todo: refactor entire zip class
697                 if (err || data === null) {
698                     entriesReadCallback(err, zip);
699                 } else {
700                     handleCentralDirectoryEnd(data, /**@type{!function(?string, !core.Zip):undefined}*/(entriesReadCallback));
701                 }
702             });
703         }
704     });
705 };
706