1 /*
2 * Copyright (C) 2006 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 //
18 // Access to Zip archives.
19 //
20
21 #define LOG_TAG "zip"
22
23 #include <utils/ZipUtils.h>
24 #include <utils/Log.h>
25
26 #include "ZipFile.h"
27
28 #include <zlib.h>
29 #define DEF_MEM_LEVEL 8 // normally in zutil.h?
30
31 #include <memory.h>
32 #include <sys/stat.h>
33 #include <errno.h>
34 #include <assert.h>
35
36 using namespace android;
37
38 /*
39 * Some environments require the "b", some choke on it.
40 */
41 #define FILE_OPEN_RO "rb"
42 #define FILE_OPEN_RW "r+b"
43 #define FILE_OPEN_RW_CREATE "w+b"
44
45 /* should live somewhere else? */
errnoToStatus(int err)46 static status_t errnoToStatus(int err)
47 {
48 if (err == ENOENT)
49 return NAME_NOT_FOUND;
50 else if (err == EACCES)
51 return PERMISSION_DENIED;
52 else
53 return UNKNOWN_ERROR;
54 }
55
56 /*
57 * Open a file and parse its guts.
58 */
open(const char * zipFileName,int flags)59 status_t ZipFile::open(const char* zipFileName, int flags)
60 {
61 bool newArchive = false;
62
63 assert(mZipFp == NULL); // no reopen
64
65 if ((flags & kOpenTruncate))
66 flags |= kOpenCreate; // trunc implies create
67
68 if ((flags & kOpenReadOnly) && (flags & kOpenReadWrite))
69 return INVALID_OPERATION; // not both
70 if (!((flags & kOpenReadOnly) || (flags & kOpenReadWrite)))
71 return INVALID_OPERATION; // not neither
72 if ((flags & kOpenCreate) && !(flags & kOpenReadWrite))
73 return INVALID_OPERATION; // create requires write
74
75 if (flags & kOpenTruncate) {
76 newArchive = true;
77 } else {
78 newArchive = (access(zipFileName, F_OK) != 0);
79 if (!(flags & kOpenCreate) && newArchive) {
80 /* not creating, must already exist */
81 LOGD("File %s does not exist", zipFileName);
82 return NAME_NOT_FOUND;
83 }
84 }
85
86 /* open the file */
87 const char* openflags;
88 if (flags & kOpenReadWrite) {
89 if (newArchive)
90 openflags = FILE_OPEN_RW_CREATE;
91 else
92 openflags = FILE_OPEN_RW;
93 } else {
94 openflags = FILE_OPEN_RO;
95 }
96 mZipFp = fopen(zipFileName, openflags);
97 if (mZipFp == NULL) {
98 int err = errno;
99 LOGD("fopen failed: %d\n", err);
100 return errnoToStatus(err);
101 }
102
103 status_t result;
104 if (!newArchive) {
105 /*
106 * Load the central directory. If that fails, then this probably
107 * isn't a Zip archive.
108 */
109 result = readCentralDir();
110 } else {
111 /*
112 * Newly-created. The EndOfCentralDir constructor actually
113 * sets everything to be the way we want it (all zeroes). We
114 * set mNeedCDRewrite so that we create *something* if the
115 * caller doesn't add any files. (We could also just unlink
116 * the file if it's brand new and nothing was added, but that's
117 * probably doing more than we really should -- the user might
118 * have a need for empty zip files.)
119 */
120 mNeedCDRewrite = true;
121 result = NO_ERROR;
122 }
123
124 if (flags & kOpenReadOnly)
125 mReadOnly = true;
126 else
127 assert(!mReadOnly);
128
129 return result;
130 }
131
132 /*
133 * Return the Nth entry in the archive.
134 */
getEntryByIndex(int idx) const135 ZipEntry* ZipFile::getEntryByIndex(int idx) const
136 {
137 if (idx < 0 || idx >= (int) mEntries.size())
138 return NULL;
139
140 return mEntries[idx];
141 }
142
143 /*
144 * Find an entry by name.
145 */
getEntryByName(const char * fileName) const146 ZipEntry* ZipFile::getEntryByName(const char* fileName) const
147 {
148 /*
149 * Do a stupid linear string-compare search.
150 *
151 * There are various ways to speed this up, especially since it's rare
152 * to intermingle changes to the archive with "get by name" calls. We
153 * don't want to sort the mEntries vector itself, however, because
154 * it's used to recreate the Central Directory.
155 *
156 * (Hash table works, parallel list of pointers in sorted order is good.)
157 */
158 int idx;
159
160 for (idx = mEntries.size()-1; idx >= 0; idx--) {
161 ZipEntry* pEntry = mEntries[idx];
162 if (!pEntry->getDeleted() &&
163 strcmp(fileName, pEntry->getFileName()) == 0)
164 {
165 return pEntry;
166 }
167 }
168
169 return NULL;
170 }
171
172 /*
173 * Empty the mEntries vector.
174 */
discardEntries(void)175 void ZipFile::discardEntries(void)
176 {
177 int count = mEntries.size();
178
179 while (--count >= 0)
180 delete mEntries[count];
181
182 mEntries.clear();
183 }
184
185
186 /*
187 * Find the central directory and read the contents.
188 *
189 * The fun thing about ZIP archives is that they may or may not be
190 * readable from start to end. In some cases, notably for archives
191 * that were written to stdout, the only length information is in the
192 * central directory at the end of the file.
193 *
194 * Of course, the central directory can be followed by a variable-length
195 * comment field, so we have to scan through it backwards. The comment
196 * is at most 64K, plus we have 18 bytes for the end-of-central-dir stuff
197 * itself, plus apparently sometimes people throw random junk on the end
198 * just for the fun of it.
199 *
200 * This is all a little wobbly. If the wrong value ends up in the EOCD
201 * area, we're hosed. This appears to be the way that everbody handles
202 * it though, so we're in pretty good company if this fails.
203 */
readCentralDir(void)204 status_t ZipFile::readCentralDir(void)
205 {
206 status_t result = NO_ERROR;
207 unsigned char* buf = NULL;
208 off_t fileLength, seekStart;
209 long readAmount;
210 int i;
211
212 fseek(mZipFp, 0, SEEK_END);
213 fileLength = ftell(mZipFp);
214 rewind(mZipFp);
215
216 /* too small to be a ZIP archive? */
217 if (fileLength < EndOfCentralDir::kEOCDLen) {
218 LOGD("Length is %ld -- too small\n", (long)fileLength);
219 result = INVALID_OPERATION;
220 goto bail;
221 }
222
223 buf = new unsigned char[EndOfCentralDir::kMaxEOCDSearch];
224 if (buf == NULL) {
225 LOGD("Failure allocating %d bytes for EOCD search",
226 EndOfCentralDir::kMaxEOCDSearch);
227 result = NO_MEMORY;
228 goto bail;
229 }
230
231 if (fileLength > EndOfCentralDir::kMaxEOCDSearch) {
232 seekStart = fileLength - EndOfCentralDir::kMaxEOCDSearch;
233 readAmount = EndOfCentralDir::kMaxEOCDSearch;
234 } else {
235 seekStart = 0;
236 readAmount = (long) fileLength;
237 }
238 if (fseek(mZipFp, seekStart, SEEK_SET) != 0) {
239 LOGD("Failure seeking to end of zip at %ld", (long) seekStart);
240 result = UNKNOWN_ERROR;
241 goto bail;
242 }
243
244 /* read the last part of the file into the buffer */
245 if (fread(buf, 1, readAmount, mZipFp) != (size_t) readAmount) {
246 LOGD("short file? wanted %ld\n", readAmount);
247 result = UNKNOWN_ERROR;
248 goto bail;
249 }
250
251 /* find the end-of-central-dir magic */
252 for (i = readAmount - 4; i >= 0; i--) {
253 if (buf[i] == 0x50 &&
254 ZipEntry::getLongLE(&buf[i]) == EndOfCentralDir::kSignature)
255 {
256 LOGV("+++ Found EOCD at buf+%d\n", i);
257 break;
258 }
259 }
260 if (i < 0) {
261 LOGD("EOCD not found, not Zip\n");
262 result = INVALID_OPERATION;
263 goto bail;
264 }
265
266 /* extract eocd values */
267 result = mEOCD.readBuf(buf + i, readAmount - i);
268 if (result != NO_ERROR) {
269 LOGD("Failure reading %ld bytes of EOCD values", readAmount - i);
270 goto bail;
271 }
272 //mEOCD.dump();
273
274 if (mEOCD.mDiskNumber != 0 || mEOCD.mDiskWithCentralDir != 0 ||
275 mEOCD.mNumEntries != mEOCD.mTotalNumEntries)
276 {
277 LOGD("Archive spanning not supported\n");
278 result = INVALID_OPERATION;
279 goto bail;
280 }
281
282 /*
283 * So far so good. "mCentralDirSize" is the size in bytes of the
284 * central directory, so we can just seek back that far to find it.
285 * We can also seek forward mCentralDirOffset bytes from the
286 * start of the file.
287 *
288 * We're not guaranteed to have the rest of the central dir in the
289 * buffer, nor are we guaranteed that the central dir will have any
290 * sort of convenient size. We need to skip to the start of it and
291 * read the header, then the other goodies.
292 *
293 * The only thing we really need right now is the file comment, which
294 * we're hoping to preserve.
295 */
296 if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
297 LOGD("Failure seeking to central dir offset %ld\n",
298 mEOCD.mCentralDirOffset);
299 result = UNKNOWN_ERROR;
300 goto bail;
301 }
302
303 /*
304 * Loop through and read the central dir entries.
305 */
306 LOGV("Scanning %d entries...\n", mEOCD.mTotalNumEntries);
307 int entry;
308 for (entry = 0; entry < mEOCD.mTotalNumEntries; entry++) {
309 ZipEntry* pEntry = new ZipEntry;
310
311 result = pEntry->initFromCDE(mZipFp);
312 if (result != NO_ERROR) {
313 LOGD("initFromCDE failed\n");
314 delete pEntry;
315 goto bail;
316 }
317
318 mEntries.add(pEntry);
319 }
320
321
322 /*
323 * If all went well, we should now be back at the EOCD.
324 */
325 {
326 unsigned char checkBuf[4];
327 if (fread(checkBuf, 1, 4, mZipFp) != 4) {
328 LOGD("EOCD check read failed\n");
329 result = INVALID_OPERATION;
330 goto bail;
331 }
332 if (ZipEntry::getLongLE(checkBuf) != EndOfCentralDir::kSignature) {
333 LOGD("EOCD read check failed\n");
334 result = UNKNOWN_ERROR;
335 goto bail;
336 }
337 LOGV("+++ EOCD read check passed\n");
338 }
339
340 bail:
341 delete[] buf;
342 return result;
343 }
344
345
346 /*
347 * Add a new file to the archive.
348 *
349 * This requires creating and populating a ZipEntry structure, and copying
350 * the data into the file at the appropriate position. The "appropriate
351 * position" is the current location of the central directory, which we
352 * casually overwrite (we can put it back later).
353 *
354 * If we were concerned about safety, we would want to make all changes
355 * in a temp file and then overwrite the original after everything was
356 * safely written. Not really a concern for us.
357 */
addCommon(const char * fileName,const void * data,size_t size,const char * storageName,int sourceType,int compressionMethod,ZipEntry ** ppEntry)358 status_t ZipFile::addCommon(const char* fileName, const void* data, size_t size,
359 const char* storageName, int sourceType, int compressionMethod,
360 ZipEntry** ppEntry)
361 {
362 ZipEntry* pEntry = NULL;
363 status_t result = NO_ERROR;
364 long lfhPosn, startPosn, endPosn, uncompressedLen;
365 FILE* inputFp = NULL;
366 unsigned long crc;
367 time_t modWhen;
368
369 if (mReadOnly)
370 return INVALID_OPERATION;
371
372 assert(compressionMethod == ZipEntry::kCompressDeflated ||
373 compressionMethod == ZipEntry::kCompressStored);
374
375 /* make sure we're in a reasonable state */
376 assert(mZipFp != NULL);
377 assert(mEntries.size() == mEOCD.mTotalNumEntries);
378
379 /* make sure it doesn't already exist */
380 if (getEntryByName(storageName) != NULL)
381 return ALREADY_EXISTS;
382
383 if (!data) {
384 inputFp = fopen(fileName, FILE_OPEN_RO);
385 if (inputFp == NULL)
386 return errnoToStatus(errno);
387 }
388
389 if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
390 result = UNKNOWN_ERROR;
391 goto bail;
392 }
393
394 pEntry = new ZipEntry;
395 pEntry->initNew(storageName, NULL);
396
397 /*
398 * From here on out, failures are more interesting.
399 */
400 mNeedCDRewrite = true;
401
402 /*
403 * Write the LFH, even though it's still mostly blank. We need it
404 * as a place-holder. In theory the LFH isn't necessary, but in
405 * practice some utilities demand it.
406 */
407 lfhPosn = ftell(mZipFp);
408 pEntry->mLFH.write(mZipFp);
409 startPosn = ftell(mZipFp);
410
411 /*
412 * Copy the data in, possibly compressing it as we go.
413 */
414 if (sourceType == ZipEntry::kCompressStored) {
415 if (compressionMethod == ZipEntry::kCompressDeflated) {
416 bool failed = false;
417 result = compressFpToFp(mZipFp, inputFp, data, size, &crc);
418 if (result != NO_ERROR) {
419 LOGD("compression failed, storing\n");
420 failed = true;
421 } else {
422 /*
423 * Make sure it has compressed "enough". This probably ought
424 * to be set through an API call, but I don't expect our
425 * criteria to change over time.
426 */
427 long src = inputFp ? ftell(inputFp) : size;
428 long dst = ftell(mZipFp) - startPosn;
429 if (dst + (dst / 10) > src) {
430 LOGD("insufficient compression (src=%ld dst=%ld), storing\n",
431 src, dst);
432 failed = true;
433 }
434 }
435
436 if (failed) {
437 compressionMethod = ZipEntry::kCompressStored;
438 if (inputFp) rewind(inputFp);
439 fseek(mZipFp, startPosn, SEEK_SET);
440 /* fall through to kCompressStored case */
441 }
442 }
443 /* handle "no compression" request, or failed compression from above */
444 if (compressionMethod == ZipEntry::kCompressStored) {
445 if (inputFp) {
446 result = copyFpToFp(mZipFp, inputFp, &crc);
447 } else {
448 result = copyDataToFp(mZipFp, data, size, &crc);
449 }
450 if (result != NO_ERROR) {
451 // don't need to truncate; happens in CDE rewrite
452 LOGD("failed copying data in\n");
453 goto bail;
454 }
455 }
456
457 // currently seeked to end of file
458 uncompressedLen = inputFp ? ftell(inputFp) : size;
459 } else if (sourceType == ZipEntry::kCompressDeflated) {
460 /* we should support uncompressed-from-compressed, but it's not
461 * important right now */
462 assert(compressionMethod == ZipEntry::kCompressDeflated);
463
464 bool scanResult;
465 int method;
466 long compressedLen;
467
468 scanResult = ZipUtils::examineGzip(inputFp, &method, &uncompressedLen,
469 &compressedLen, &crc);
470 if (!scanResult || method != ZipEntry::kCompressDeflated) {
471 LOGD("this isn't a deflated gzip file?");
472 result = UNKNOWN_ERROR;
473 goto bail;
474 }
475
476 result = copyPartialFpToFp(mZipFp, inputFp, compressedLen, NULL);
477 if (result != NO_ERROR) {
478 LOGD("failed copying gzip data in\n");
479 goto bail;
480 }
481 } else {
482 assert(false);
483 result = UNKNOWN_ERROR;
484 goto bail;
485 }
486
487 /*
488 * We could write the "Data Descriptor", but there doesn't seem to
489 * be any point since we're going to go back and write the LFH.
490 *
491 * Update file offsets.
492 */
493 endPosn = ftell(mZipFp); // seeked to end of compressed data
494
495 /*
496 * Success! Fill out new values.
497 */
498 pEntry->setDataInfo(uncompressedLen, endPosn - startPosn, crc,
499 compressionMethod);
500 modWhen = getModTime(inputFp ? fileno(inputFp) : fileno(mZipFp));
501 pEntry->setModWhen(modWhen);
502 pEntry->setLFHOffset(lfhPosn);
503 mEOCD.mNumEntries++;
504 mEOCD.mTotalNumEntries++;
505 mEOCD.mCentralDirSize = 0; // mark invalid; set by flush()
506 mEOCD.mCentralDirOffset = endPosn;
507
508 /*
509 * Go back and write the LFH.
510 */
511 if (fseek(mZipFp, lfhPosn, SEEK_SET) != 0) {
512 result = UNKNOWN_ERROR;
513 goto bail;
514 }
515 pEntry->mLFH.write(mZipFp);
516
517 /*
518 * Add pEntry to the list.
519 */
520 mEntries.add(pEntry);
521 if (ppEntry != NULL)
522 *ppEntry = pEntry;
523 pEntry = NULL;
524
525 bail:
526 if (inputFp != NULL)
527 fclose(inputFp);
528 delete pEntry;
529 return result;
530 }
531
532 /*
533 * Add an entry by copying it from another zip file. If "padding" is
534 * nonzero, the specified number of bytes will be added to the "extra"
535 * field in the header.
536 *
537 * If "ppEntry" is non-NULL, a pointer to the new entry will be returned.
538 */
add(const ZipFile * pSourceZip,const ZipEntry * pSourceEntry,int padding,ZipEntry ** ppEntry)539 status_t ZipFile::add(const ZipFile* pSourceZip, const ZipEntry* pSourceEntry,
540 int padding, ZipEntry** ppEntry)
541 {
542 ZipEntry* pEntry = NULL;
543 status_t result;
544 long lfhPosn, endPosn;
545
546 if (mReadOnly)
547 return INVALID_OPERATION;
548
549 /* make sure we're in a reasonable state */
550 assert(mZipFp != NULL);
551 assert(mEntries.size() == mEOCD.mTotalNumEntries);
552
553 if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
554 result = UNKNOWN_ERROR;
555 goto bail;
556 }
557
558 pEntry = new ZipEntry;
559 if (pEntry == NULL) {
560 result = NO_MEMORY;
561 goto bail;
562 }
563
564 result = pEntry->initFromExternal(pSourceZip, pSourceEntry);
565 if (result != NO_ERROR)
566 goto bail;
567 if (padding != 0) {
568 result = pEntry->addPadding(padding);
569 if (result != NO_ERROR)
570 goto bail;
571 }
572
573 /*
574 * From here on out, failures are more interesting.
575 */
576 mNeedCDRewrite = true;
577
578 /*
579 * Write the LFH. Since we're not recompressing the data, we already
580 * have all of the fields filled out.
581 */
582 lfhPosn = ftell(mZipFp);
583 pEntry->mLFH.write(mZipFp);
584
585 /*
586 * Copy the data over.
587 *
588 * If the "has data descriptor" flag is set, we want to copy the DD
589 * fields as well. This is a fixed-size area immediately following
590 * the data.
591 */
592 if (fseek(pSourceZip->mZipFp, pSourceEntry->getFileOffset(), SEEK_SET) != 0)
593 {
594 result = UNKNOWN_ERROR;
595 goto bail;
596 }
597
598 off_t copyLen;
599 copyLen = pSourceEntry->getCompressedLen();
600 if ((pSourceEntry->mLFH.mGPBitFlag & ZipEntry::kUsesDataDescr) != 0)
601 copyLen += ZipEntry::kDataDescriptorLen;
602
603 if (copyPartialFpToFp(mZipFp, pSourceZip->mZipFp, copyLen, NULL)
604 != NO_ERROR)
605 {
606 LOGW("copy of '%s' failed\n", pEntry->mCDE.mFileName);
607 result = UNKNOWN_ERROR;
608 goto bail;
609 }
610
611 /*
612 * Update file offsets.
613 */
614 endPosn = ftell(mZipFp);
615
616 /*
617 * Success! Fill out new values.
618 */
619 pEntry->setLFHOffset(lfhPosn); // sets mCDE.mLocalHeaderRelOffset
620 mEOCD.mNumEntries++;
621 mEOCD.mTotalNumEntries++;
622 mEOCD.mCentralDirSize = 0; // mark invalid; set by flush()
623 mEOCD.mCentralDirOffset = endPosn;
624
625 /*
626 * Add pEntry to the list.
627 */
628 mEntries.add(pEntry);
629 if (ppEntry != NULL)
630 *ppEntry = pEntry;
631 pEntry = NULL;
632
633 result = NO_ERROR;
634
635 bail:
636 delete pEntry;
637 return result;
638 }
639
640 /*
641 * Copy all of the bytes in "src" to "dst".
642 *
643 * On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
644 * will be seeked immediately past the data.
645 */
copyFpToFp(FILE * dstFp,FILE * srcFp,unsigned long * pCRC32)646 status_t ZipFile::copyFpToFp(FILE* dstFp, FILE* srcFp, unsigned long* pCRC32)
647 {
648 unsigned char tmpBuf[32768];
649 size_t count;
650
651 *pCRC32 = crc32(0L, Z_NULL, 0);
652
653 while (1) {
654 count = fread(tmpBuf, 1, sizeof(tmpBuf), srcFp);
655 if (ferror(srcFp) || ferror(dstFp))
656 return errnoToStatus(errno);
657 if (count == 0)
658 break;
659
660 *pCRC32 = crc32(*pCRC32, tmpBuf, count);
661
662 if (fwrite(tmpBuf, 1, count, dstFp) != count) {
663 LOGD("fwrite %d bytes failed\n", (int) count);
664 return UNKNOWN_ERROR;
665 }
666 }
667
668 return NO_ERROR;
669 }
670
671 /*
672 * Copy all of the bytes in "src" to "dst".
673 *
674 * On exit, "dstFp" will be seeked immediately past the data.
675 */
copyDataToFp(FILE * dstFp,const void * data,size_t size,unsigned long * pCRC32)676 status_t ZipFile::copyDataToFp(FILE* dstFp,
677 const void* data, size_t size, unsigned long* pCRC32)
678 {
679 size_t count;
680
681 *pCRC32 = crc32(0L, Z_NULL, 0);
682 if (size > 0) {
683 *pCRC32 = crc32(*pCRC32, (const unsigned char*)data, size);
684 if (fwrite(data, 1, size, dstFp) != size) {
685 LOGD("fwrite %d bytes failed\n", (int) size);
686 return UNKNOWN_ERROR;
687 }
688 }
689
690 return NO_ERROR;
691 }
692
693 /*
694 * Copy some of the bytes in "src" to "dst".
695 *
696 * If "pCRC32" is NULL, the CRC will not be computed.
697 *
698 * On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
699 * will be seeked immediately past the data just written.
700 */
copyPartialFpToFp(FILE * dstFp,FILE * srcFp,long length,unsigned long * pCRC32)701 status_t ZipFile::copyPartialFpToFp(FILE* dstFp, FILE* srcFp, long length,
702 unsigned long* pCRC32)
703 {
704 unsigned char tmpBuf[32768];
705 size_t count;
706
707 if (pCRC32 != NULL)
708 *pCRC32 = crc32(0L, Z_NULL, 0);
709
710 while (length) {
711 long readSize;
712
713 readSize = sizeof(tmpBuf);
714 if (readSize > length)
715 readSize = length;
716
717 count = fread(tmpBuf, 1, readSize, srcFp);
718 if ((long) count != readSize) { // error or unexpected EOF
719 LOGD("fread %d bytes failed\n", (int) readSize);
720 return UNKNOWN_ERROR;
721 }
722
723 if (pCRC32 != NULL)
724 *pCRC32 = crc32(*pCRC32, tmpBuf, count);
725
726 if (fwrite(tmpBuf, 1, count, dstFp) != count) {
727 LOGD("fwrite %d bytes failed\n", (int) count);
728 return UNKNOWN_ERROR;
729 }
730
731 length -= readSize;
732 }
733
734 return NO_ERROR;
735 }
736
737 /*
738 * Compress all of the data in "srcFp" and write it to "dstFp".
739 *
740 * On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
741 * will be seeked immediately past the compressed data.
742 */
compressFpToFp(FILE * dstFp,FILE * srcFp,const void * data,size_t size,unsigned long * pCRC32)743 status_t ZipFile::compressFpToFp(FILE* dstFp, FILE* srcFp,
744 const void* data, size_t size, unsigned long* pCRC32)
745 {
746 status_t result = NO_ERROR;
747 const size_t kBufSize = 32768;
748 unsigned char* inBuf = NULL;
749 unsigned char* outBuf = NULL;
750 z_stream zstream;
751 bool atEof = false; // no feof() aviailable yet
752 unsigned long crc;
753 int zerr;
754
755 /*
756 * Create an input buffer and an output buffer.
757 */
758 inBuf = new unsigned char[kBufSize];
759 outBuf = new unsigned char[kBufSize];
760 if (inBuf == NULL || outBuf == NULL) {
761 result = NO_MEMORY;
762 goto bail;
763 }
764
765 /*
766 * Initialize the zlib stream.
767 */
768 memset(&zstream, 0, sizeof(zstream));
769 zstream.zalloc = Z_NULL;
770 zstream.zfree = Z_NULL;
771 zstream.opaque = Z_NULL;
772 zstream.next_in = NULL;
773 zstream.avail_in = 0;
774 zstream.next_out = outBuf;
775 zstream.avail_out = kBufSize;
776 zstream.data_type = Z_UNKNOWN;
777
778 zerr = deflateInit2(&zstream, Z_BEST_COMPRESSION,
779 Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY);
780 if (zerr != Z_OK) {
781 result = UNKNOWN_ERROR;
782 if (zerr == Z_VERSION_ERROR) {
783 LOGE("Installed zlib is not compatible with linked version (%s)\n",
784 ZLIB_VERSION);
785 } else {
786 LOGD("Call to deflateInit2 failed (zerr=%d)\n", zerr);
787 }
788 goto bail;
789 }
790
791 crc = crc32(0L, Z_NULL, 0);
792
793 /*
794 * Loop while we have data.
795 */
796 do {
797 size_t getSize;
798 int flush;
799
800 /* only read if the input buffer is empty */
801 if (zstream.avail_in == 0 && !atEof) {
802 LOGV("+++ reading %d bytes\n", (int)kBufSize);
803 if (data) {
804 getSize = size > kBufSize ? kBufSize : size;
805 memcpy(inBuf, data, getSize);
806 data = ((const char*)data) + getSize;
807 size -= getSize;
808 } else {
809 getSize = fread(inBuf, 1, kBufSize, srcFp);
810 if (ferror(srcFp)) {
811 LOGD("deflate read failed (errno=%d)\n", errno);
812 goto z_bail;
813 }
814 }
815 if (getSize < kBufSize) {
816 LOGV("+++ got %d bytes, EOF reached\n",
817 (int)getSize);
818 atEof = true;
819 }
820
821 crc = crc32(crc, inBuf, getSize);
822
823 zstream.next_in = inBuf;
824 zstream.avail_in = getSize;
825 }
826
827 if (atEof)
828 flush = Z_FINISH; /* tell zlib that we're done */
829 else
830 flush = Z_NO_FLUSH; /* more to come! */
831
832 zerr = deflate(&zstream, flush);
833 if (zerr != Z_OK && zerr != Z_STREAM_END) {
834 LOGD("zlib deflate call failed (zerr=%d)\n", zerr);
835 result = UNKNOWN_ERROR;
836 goto z_bail;
837 }
838
839 /* write when we're full or when we're done */
840 if (zstream.avail_out == 0 ||
841 (zerr == Z_STREAM_END && zstream.avail_out != (uInt) kBufSize))
842 {
843 LOGV("+++ writing %d bytes\n", (int) (zstream.next_out - outBuf));
844 if (fwrite(outBuf, 1, zstream.next_out - outBuf, dstFp) !=
845 (size_t)(zstream.next_out - outBuf))
846 {
847 LOGD("write %d failed in deflate\n",
848 (int) (zstream.next_out - outBuf));
849 goto z_bail;
850 }
851
852 zstream.next_out = outBuf;
853 zstream.avail_out = kBufSize;
854 }
855 } while (zerr == Z_OK);
856
857 assert(zerr == Z_STREAM_END); /* other errors should've been caught */
858
859 *pCRC32 = crc;
860
861 z_bail:
862 deflateEnd(&zstream); /* free up any allocated structures */
863
864 bail:
865 delete[] inBuf;
866 delete[] outBuf;
867
868 return result;
869 }
870
871 /*
872 * Mark an entry as deleted.
873 *
874 * We will eventually need to crunch the file down, but if several files
875 * are being removed (perhaps as part of an "update" process) we can make
876 * things considerably faster by deferring the removal to "flush" time.
877 */
remove(ZipEntry * pEntry)878 status_t ZipFile::remove(ZipEntry* pEntry)
879 {
880 /*
881 * Should verify that pEntry is actually part of this archive, and
882 * not some stray ZipEntry from a different file.
883 */
884
885 /* mark entry as deleted, and mark archive as dirty */
886 pEntry->setDeleted();
887 mNeedCDRewrite = true;
888 return NO_ERROR;
889 }
890
891 /*
892 * Flush any pending writes.
893 *
894 * In particular, this will crunch out deleted entries, and write the
895 * Central Directory and EOCD if we have stomped on them.
896 */
flush(void)897 status_t ZipFile::flush(void)
898 {
899 status_t result = NO_ERROR;
900 long eocdPosn;
901 int i, count;
902
903 if (mReadOnly)
904 return INVALID_OPERATION;
905 if (!mNeedCDRewrite)
906 return NO_ERROR;
907
908 assert(mZipFp != NULL);
909
910 result = crunchArchive();
911 if (result != NO_ERROR)
912 return result;
913
914 if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0)
915 return UNKNOWN_ERROR;
916
917 count = mEntries.size();
918 for (i = 0; i < count; i++) {
919 ZipEntry* pEntry = mEntries[i];
920 pEntry->mCDE.write(mZipFp);
921 }
922
923 eocdPosn = ftell(mZipFp);
924 mEOCD.mCentralDirSize = eocdPosn - mEOCD.mCentralDirOffset;
925
926 mEOCD.write(mZipFp);
927
928 /*
929 * If we had some stuff bloat up during compression and get replaced
930 * with plain files, or if we deleted some entries, there's a lot
931 * of wasted space at the end of the file. Remove it now.
932 */
933 if (ftruncate(fileno(mZipFp), ftell(mZipFp)) != 0) {
934 LOGW("ftruncate failed %ld: %s\n", ftell(mZipFp), strerror(errno));
935 // not fatal
936 }
937
938 /* should we clear the "newly added" flag in all entries now? */
939
940 mNeedCDRewrite = false;
941 return NO_ERROR;
942 }
943
944 /*
945 * Crunch deleted files out of an archive by shifting the later files down.
946 *
947 * Because we're not using a temp file, we do the operation inside the
948 * current file.
949 */
crunchArchive(void)950 status_t ZipFile::crunchArchive(void)
951 {
952 status_t result = NO_ERROR;
953 int i, count;
954 long delCount, adjust;
955
956 #if 0
957 printf("CONTENTS:\n");
958 for (i = 0; i < (int) mEntries.size(); i++) {
959 printf(" %d: lfhOff=%ld del=%d\n",
960 i, mEntries[i]->getLFHOffset(), mEntries[i]->getDeleted());
961 }
962 printf(" END is %ld\n", (long) mEOCD.mCentralDirOffset);
963 #endif
964
965 /*
966 * Roll through the set of files, shifting them as appropriate. We
967 * could probably get a slight performance improvement by sliding
968 * multiple files down at once (because we could use larger reads
969 * when operating on batches of small files), but it's not that useful.
970 */
971 count = mEntries.size();
972 delCount = adjust = 0;
973 for (i = 0; i < count; i++) {
974 ZipEntry* pEntry = mEntries[i];
975 long span;
976
977 if (pEntry->getLFHOffset() != 0) {
978 long nextOffset;
979
980 /* Get the length of this entry by finding the offset
981 * of the next entry. Directory entries don't have
982 * file offsets, so we need to find the next non-directory
983 * entry.
984 */
985 nextOffset = 0;
986 for (int ii = i+1; nextOffset == 0 && ii < count; ii++)
987 nextOffset = mEntries[ii]->getLFHOffset();
988 if (nextOffset == 0)
989 nextOffset = mEOCD.mCentralDirOffset;
990 span = nextOffset - pEntry->getLFHOffset();
991
992 assert(span >= ZipEntry::LocalFileHeader::kLFHLen);
993 } else {
994 /* This is a directory entry. It doesn't have
995 * any actual file contents, so there's no need to
996 * move anything.
997 */
998 span = 0;
999 }
1000
1001 //printf("+++ %d: off=%ld span=%ld del=%d [count=%d]\n",
1002 // i, pEntry->getLFHOffset(), span, pEntry->getDeleted(), count);
1003
1004 if (pEntry->getDeleted()) {
1005 adjust += span;
1006 delCount++;
1007
1008 delete pEntry;
1009 mEntries.removeAt(i);
1010
1011 /* adjust loop control */
1012 count--;
1013 i--;
1014 } else if (span != 0 && adjust > 0) {
1015 /* shuffle this entry back */
1016 //printf("+++ Shuffling '%s' back %ld\n",
1017 // pEntry->getFileName(), adjust);
1018 result = filemove(mZipFp, pEntry->getLFHOffset() - adjust,
1019 pEntry->getLFHOffset(), span);
1020 if (result != NO_ERROR) {
1021 /* this is why you use a temp file */
1022 LOGE("error during crunch - archive is toast\n");
1023 return result;
1024 }
1025
1026 pEntry->setLFHOffset(pEntry->getLFHOffset() - adjust);
1027 }
1028 }
1029
1030 /*
1031 * Fix EOCD info. We have to wait until the end to do some of this
1032 * because we use mCentralDirOffset to determine "span" for the
1033 * last entry.
1034 */
1035 mEOCD.mCentralDirOffset -= adjust;
1036 mEOCD.mNumEntries -= delCount;
1037 mEOCD.mTotalNumEntries -= delCount;
1038 mEOCD.mCentralDirSize = 0; // mark invalid; set by flush()
1039
1040 assert(mEOCD.mNumEntries == mEOCD.mTotalNumEntries);
1041 assert(mEOCD.mNumEntries == count);
1042
1043 return result;
1044 }
1045
1046 /*
1047 * Works like memmove(), but on pieces of a file.
1048 */
filemove(FILE * fp,off_t dst,off_t src,size_t n)1049 status_t ZipFile::filemove(FILE* fp, off_t dst, off_t src, size_t n)
1050 {
1051 if (dst == src || n <= 0)
1052 return NO_ERROR;
1053
1054 unsigned char readBuf[32768];
1055
1056 if (dst < src) {
1057 /* shift stuff toward start of file; must read from start */
1058 while (n != 0) {
1059 size_t getSize = sizeof(readBuf);
1060 if (getSize > n)
1061 getSize = n;
1062
1063 if (fseek(fp, (long) src, SEEK_SET) != 0) {
1064 LOGD("filemove src seek %ld failed\n", (long) src);
1065 return UNKNOWN_ERROR;
1066 }
1067
1068 if (fread(readBuf, 1, getSize, fp) != getSize) {
1069 LOGD("filemove read %ld off=%ld failed\n",
1070 (long) getSize, (long) src);
1071 return UNKNOWN_ERROR;
1072 }
1073
1074 if (fseek(fp, (long) dst, SEEK_SET) != 0) {
1075 LOGD("filemove dst seek %ld failed\n", (long) dst);
1076 return UNKNOWN_ERROR;
1077 }
1078
1079 if (fwrite(readBuf, 1, getSize, fp) != getSize) {
1080 LOGD("filemove write %ld off=%ld failed\n",
1081 (long) getSize, (long) dst);
1082 return UNKNOWN_ERROR;
1083 }
1084
1085 src += getSize;
1086 dst += getSize;
1087 n -= getSize;
1088 }
1089 } else {
1090 /* shift stuff toward end of file; must read from end */
1091 assert(false); // write this someday, maybe
1092 return UNKNOWN_ERROR;
1093 }
1094
1095 return NO_ERROR;
1096 }
1097
1098
1099 /*
1100 * Get the modification time from a file descriptor.
1101 */
getModTime(int fd)1102 time_t ZipFile::getModTime(int fd)
1103 {
1104 struct stat sb;
1105
1106 if (fstat(fd, &sb) < 0) {
1107 LOGD("HEY: fstat on fd %d failed\n", fd);
1108 return (time_t) -1;
1109 }
1110
1111 return sb.st_mtime;
1112 }
1113
1114
1115 #if 0 /* this is a bad idea */
1116 /*
1117 * Get a copy of the Zip file descriptor.
1118 *
1119 * We don't allow this if the file was opened read-write because we tend
1120 * to leave the file contents in an uncertain state between calls to
1121 * flush(). The duplicated file descriptor should only be valid for reads.
1122 */
1123 int ZipFile::getZipFd(void) const
1124 {
1125 if (!mReadOnly)
1126 return INVALID_OPERATION;
1127 assert(mZipFp != NULL);
1128
1129 int fd;
1130 fd = dup(fileno(mZipFp));
1131 if (fd < 0) {
1132 LOGD("didn't work, errno=%d\n", errno);
1133 }
1134
1135 return fd;
1136 }
1137 #endif
1138
1139
1140 #if 0
1141 /*
1142 * Expand data.
1143 */
1144 bool ZipFile::uncompress(const ZipEntry* pEntry, void* buf) const
1145 {
1146 return false;
1147 }
1148 #endif
1149
1150 // free the memory when you're done
uncompress(const ZipEntry * entry)1151 void* ZipFile::uncompress(const ZipEntry* entry)
1152 {
1153 size_t unlen = entry->getUncompressedLen();
1154 size_t clen = entry->getCompressedLen();
1155
1156 void* buf = malloc(unlen);
1157 if (buf == NULL) {
1158 return NULL;
1159 }
1160
1161 fseek(mZipFp, 0, SEEK_SET);
1162
1163 off_t offset = entry->getFileOffset();
1164 if (fseek(mZipFp, offset, SEEK_SET) != 0) {
1165 goto bail;
1166 }
1167
1168 switch (entry->getCompressionMethod())
1169 {
1170 case ZipEntry::kCompressStored: {
1171 ssize_t amt = fread(buf, 1, unlen, mZipFp);
1172 if (amt != (ssize_t)unlen) {
1173 goto bail;
1174 }
1175 #if 0
1176 printf("data...\n");
1177 const unsigned char* p = (unsigned char*)buf;
1178 const unsigned char* end = p+unlen;
1179 for (int i=0; i<32 && p < end; i++) {
1180 printf("0x%08x ", (int)(offset+(i*0x10)));
1181 for (int j=0; j<0x10 && p < end; j++) {
1182 printf(" %02x", *p);
1183 p++;
1184 }
1185 printf("\n");
1186 }
1187 #endif
1188
1189 }
1190 break;
1191 case ZipEntry::kCompressDeflated: {
1192 if (!ZipUtils::inflateToBuffer(mZipFp, buf, unlen, clen)) {
1193 goto bail;
1194 }
1195 }
1196 break;
1197 default:
1198 goto bail;
1199 }
1200 return buf;
1201
1202 bail:
1203 free(buf);
1204 return NULL;
1205 }
1206
1207
1208 /*
1209 * ===========================================================================
1210 * ZipFile::EndOfCentralDir
1211 * ===========================================================================
1212 */
1213
1214 /*
1215 * Read the end-of-central-dir fields.
1216 *
1217 * "buf" should be positioned at the EOCD signature, and should contain
1218 * the entire EOCD area including the comment.
1219 */
readBuf(const unsigned char * buf,int len)1220 status_t ZipFile::EndOfCentralDir::readBuf(const unsigned char* buf, int len)
1221 {
1222 /* don't allow re-use */
1223 assert(mComment == NULL);
1224
1225 if (len < kEOCDLen) {
1226 /* looks like ZIP file got truncated */
1227 LOGD(" Zip EOCD: expected >= %d bytes, found %d\n",
1228 kEOCDLen, len);
1229 return INVALID_OPERATION;
1230 }
1231
1232 /* this should probably be an assert() */
1233 if (ZipEntry::getLongLE(&buf[0x00]) != kSignature)
1234 return UNKNOWN_ERROR;
1235
1236 mDiskNumber = ZipEntry::getShortLE(&buf[0x04]);
1237 mDiskWithCentralDir = ZipEntry::getShortLE(&buf[0x06]);
1238 mNumEntries = ZipEntry::getShortLE(&buf[0x08]);
1239 mTotalNumEntries = ZipEntry::getShortLE(&buf[0x0a]);
1240 mCentralDirSize = ZipEntry::getLongLE(&buf[0x0c]);
1241 mCentralDirOffset = ZipEntry::getLongLE(&buf[0x10]);
1242 mCommentLen = ZipEntry::getShortLE(&buf[0x14]);
1243
1244 // TODO: validate mCentralDirOffset
1245
1246 if (mCommentLen > 0) {
1247 if (kEOCDLen + mCommentLen > len) {
1248 LOGD("EOCD(%d) + comment(%d) exceeds len (%d)\n",
1249 kEOCDLen, mCommentLen, len);
1250 return UNKNOWN_ERROR;
1251 }
1252 mComment = new unsigned char[mCommentLen];
1253 memcpy(mComment, buf + kEOCDLen, mCommentLen);
1254 }
1255
1256 return NO_ERROR;
1257 }
1258
1259 /*
1260 * Write an end-of-central-directory section.
1261 */
write(FILE * fp)1262 status_t ZipFile::EndOfCentralDir::write(FILE* fp)
1263 {
1264 unsigned char buf[kEOCDLen];
1265
1266 ZipEntry::putLongLE(&buf[0x00], kSignature);
1267 ZipEntry::putShortLE(&buf[0x04], mDiskNumber);
1268 ZipEntry::putShortLE(&buf[0x06], mDiskWithCentralDir);
1269 ZipEntry::putShortLE(&buf[0x08], mNumEntries);
1270 ZipEntry::putShortLE(&buf[0x0a], mTotalNumEntries);
1271 ZipEntry::putLongLE(&buf[0x0c], mCentralDirSize);
1272 ZipEntry::putLongLE(&buf[0x10], mCentralDirOffset);
1273 ZipEntry::putShortLE(&buf[0x14], mCommentLen);
1274
1275 if (fwrite(buf, 1, kEOCDLen, fp) != kEOCDLen)
1276 return UNKNOWN_ERROR;
1277 if (mCommentLen > 0) {
1278 assert(mComment != NULL);
1279 if (fwrite(mComment, mCommentLen, 1, fp) != mCommentLen)
1280 return UNKNOWN_ERROR;
1281 }
1282
1283 return NO_ERROR;
1284 }
1285
1286 /*
1287 * Dump the contents of an EndOfCentralDir object.
1288 */
dump(void) const1289 void ZipFile::EndOfCentralDir::dump(void) const
1290 {
1291 LOGD(" EndOfCentralDir contents:\n");
1292 LOGD(" diskNum=%u diskWCD=%u numEnt=%u totalNumEnt=%u\n",
1293 mDiskNumber, mDiskWithCentralDir, mNumEntries, mTotalNumEntries);
1294 LOGD(" centDirSize=%lu centDirOff=%lu commentLen=%u\n",
1295 mCentralDirSize, mCentralDirOffset, mCommentLen);
1296 }
1297
1298