/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
//
// Access to Zip archives.
//
#define LOG_TAG "zip"
#include <androidfw/ZipUtils.h>
#include <utils/Log.h>
#include "ZipFile.h"
#include <zlib.h>
#define DEF_MEM_LEVEL 8 // normally in zutil.h?
#include <memory.h>
#include <sys/stat.h>
#include <errno.h>
#include <assert.h>
using namespace android;
/*
* Some environments require the "b", some choke on it.
*/
#define FILE_OPEN_RO "rb"
#define FILE_OPEN_RW "r+b"
#define FILE_OPEN_RW_CREATE "w+b"
/* should live somewhere else? */
static status_t errnoToStatus(int err)
{
if (err == ENOENT)
return NAME_NOT_FOUND;
else if (err == EACCES)
return PERMISSION_DENIED;
else
return UNKNOWN_ERROR;
}
/*
* Open a file and parse its guts.
*/
status_t ZipFile::open(const char* zipFileName, int flags)
{
bool newArchive = false;
assert(mZipFp == NULL); // no reopen
if ((flags & kOpenTruncate))
flags |= kOpenCreate; // trunc implies create
if ((flags & kOpenReadOnly) && (flags & kOpenReadWrite))
return INVALID_OPERATION; // not both
if (!((flags & kOpenReadOnly) || (flags & kOpenReadWrite)))
return INVALID_OPERATION; // not neither
if ((flags & kOpenCreate) && !(flags & kOpenReadWrite))
return INVALID_OPERATION; // create requires write
if (flags & kOpenTruncate) {
newArchive = true;
} else {
newArchive = (access(zipFileName, F_OK) != 0);
if (!(flags & kOpenCreate) && newArchive) {
/* not creating, must already exist */
ALOGD("File %s does not exist", zipFileName);
return NAME_NOT_FOUND;
}
}
/* open the file */
const char* openflags;
if (flags & kOpenReadWrite) {
if (newArchive)
openflags = FILE_OPEN_RW_CREATE;
else
openflags = FILE_OPEN_RW;
} else {
openflags = FILE_OPEN_RO;
}
mZipFp = fopen(zipFileName, openflags);
if (mZipFp == NULL) {
int err = errno;
ALOGD("fopen failed: %d\n", err);
return errnoToStatus(err);
}
status_t result;
if (!newArchive) {
/*
* Load the central directory. If that fails, then this probably
* isn't a Zip archive.
*/
result = readCentralDir();
} else {
/*
* Newly-created. The EndOfCentralDir constructor actually
* sets everything to be the way we want it (all zeroes). We
* set mNeedCDRewrite so that we create *something* if the
* caller doesn't add any files. (We could also just unlink
* the file if it's brand new and nothing was added, but that's
* probably doing more than we really should -- the user might
* have a need for empty zip files.)
*/
mNeedCDRewrite = true;
result = NO_ERROR;
}
if (flags & kOpenReadOnly)
mReadOnly = true;
else
assert(!mReadOnly);
return result;
}
/*
* Return the Nth entry in the archive.
*/
ZipEntry* ZipFile::getEntryByIndex(int idx) const
{
if (idx < 0 || idx >= (int) mEntries.size())
return NULL;
return mEntries[idx];
}
/*
* Find an entry by name.
*/
ZipEntry* ZipFile::getEntryByName(const char* fileName) const
{
/*
* Do a stupid linear string-compare search.
*
* There are various ways to speed this up, especially since it's rare
* to intermingle changes to the archive with "get by name" calls. We
* don't want to sort the mEntries vector itself, however, because
* it's used to recreate the Central Directory.
*
* (Hash table works, parallel list of pointers in sorted order is good.)
*/
int idx;
for (idx = mEntries.size()-1; idx >= 0; idx--) {
ZipEntry* pEntry = mEntries[idx];
if (!pEntry->getDeleted() &&
strcmp(fileName, pEntry->getFileName()) == 0)
{
return pEntry;
}
}
return NULL;
}
/*
* Empty the mEntries vector.
*/
void ZipFile::discardEntries(void)
{
int count = mEntries.size();
while (--count >= 0)
delete mEntries[count];
mEntries.clear();
}
/*
* Find the central directory and read the contents.
*
* The fun thing about ZIP archives is that they may or may not be
* readable from start to end. In some cases, notably for archives
* that were written to stdout, the only length information is in the
* central directory at the end of the file.
*
* Of course, the central directory can be followed by a variable-length
* comment field, so we have to scan through it backwards. The comment
* is at most 64K, plus we have 18 bytes for the end-of-central-dir stuff
* itself, plus apparently sometimes people throw random junk on the end
* just for the fun of it.
*
* This is all a little wobbly. If the wrong value ends up in the EOCD
* area, we're hosed. This appears to be the way that everbody handles
* it though, so we're in pretty good company if this fails.
*/
status_t ZipFile::readCentralDir(void)
{
status_t result = NO_ERROR;
unsigned char* buf = NULL;
off_t fileLength, seekStart;
long readAmount;
int i;
fseek(mZipFp, 0, SEEK_END);
fileLength = ftell(mZipFp);
rewind(mZipFp);
/* too small to be a ZIP archive? */
if (fileLength < EndOfCentralDir::kEOCDLen) {
ALOGD("Length is %ld -- too small\n", (long)fileLength);
result = INVALID_OPERATION;
goto bail;
}
buf = new unsigned char[EndOfCentralDir::kMaxEOCDSearch];
if (buf == NULL) {
ALOGD("Failure allocating %d bytes for EOCD search",
EndOfCentralDir::kMaxEOCDSearch);
result = NO_MEMORY;
goto bail;
}
if (fileLength > EndOfCentralDir::kMaxEOCDSearch) {
seekStart = fileLength - EndOfCentralDir::kMaxEOCDSearch;
readAmount = EndOfCentralDir::kMaxEOCDSearch;
} else {
seekStart = 0;
readAmount = (long) fileLength;
}
if (fseek(mZipFp, seekStart, SEEK_SET) != 0) {
ALOGD("Failure seeking to end of zip at %ld", (long) seekStart);
result = UNKNOWN_ERROR;
goto bail;
}
/* read the last part of the file into the buffer */
if (fread(buf, 1, readAmount, mZipFp) != (size_t) readAmount) {
ALOGD("short file? wanted %ld\n", readAmount);
result = UNKNOWN_ERROR;
goto bail;
}
/* find the end-of-central-dir magic */
for (i = readAmount - 4; i >= 0; i--) {
if (buf[i] == 0x50 &&
ZipEntry::getLongLE(&buf[i]) == EndOfCentralDir::kSignature)
{
ALOGV("+++ Found EOCD at buf+%d\n", i);
break;
}
}
if (i < 0) {
ALOGD("EOCD not found, not Zip\n");
result = INVALID_OPERATION;
goto bail;
}
/* extract eocd values */
result = mEOCD.readBuf(buf + i, readAmount - i);
if (result != NO_ERROR) {
ALOGD("Failure reading %ld bytes of EOCD values", readAmount - i);
goto bail;
}
//mEOCD.dump();
if (mEOCD.mDiskNumber != 0 || mEOCD.mDiskWithCentralDir != 0 ||
mEOCD.mNumEntries != mEOCD.mTotalNumEntries)
{
ALOGD("Archive spanning not supported\n");
result = INVALID_OPERATION;
goto bail;
}
/*
* So far so good. "mCentralDirSize" is the size in bytes of the
* central directory, so we can just seek back that far to find it.
* We can also seek forward mCentralDirOffset bytes from the
* start of the file.
*
* We're not guaranteed to have the rest of the central dir in the
* buffer, nor are we guaranteed that the central dir will have any
* sort of convenient size. We need to skip to the start of it and
* read the header, then the other goodies.
*
* The only thing we really need right now is the file comment, which
* we're hoping to preserve.
*/
if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
ALOGD("Failure seeking to central dir offset %ld\n",
mEOCD.mCentralDirOffset);
result = UNKNOWN_ERROR;
goto bail;
}
/*
* Loop through and read the central dir entries.
*/
ALOGV("Scanning %d entries...\n", mEOCD.mTotalNumEntries);
int entry;
for (entry = 0; entry < mEOCD.mTotalNumEntries; entry++) {
ZipEntry* pEntry = new ZipEntry;
result = pEntry->initFromCDE(mZipFp);
if (result != NO_ERROR) {
ALOGD("initFromCDE failed\n");
delete pEntry;
goto bail;
}
mEntries.add(pEntry);
}
/*
* If all went well, we should now be back at the EOCD.
*/
{
unsigned char checkBuf[4];
if (fread(checkBuf, 1, 4, mZipFp) != 4) {
ALOGD("EOCD check read failed\n");
result = INVALID_OPERATION;
goto bail;
}
if (ZipEntry::getLongLE(checkBuf) != EndOfCentralDir::kSignature) {
ALOGD("EOCD read check failed\n");
result = UNKNOWN_ERROR;
goto bail;
}
ALOGV("+++ EOCD read check passed\n");
}
bail:
delete[] buf;
return result;
}
/*
* Add a new file to the archive.
*
* This requires creating and populating a ZipEntry structure, and copying
* the data into the file at the appropriate position. The "appropriate
* position" is the current location of the central directory, which we
* casually overwrite (we can put it back later).
*
* If we were concerned about safety, we would want to make all changes
* in a temp file and then overwrite the original after everything was
* safely written. Not really a concern for us.
*/
status_t ZipFile::addCommon(const char* fileName, const void* data, size_t size,
const char* storageName, int sourceType, int compressionMethod,
ZipEntry** ppEntry)
{
ZipEntry* pEntry = NULL;
status_t result = NO_ERROR;
long lfhPosn, startPosn, endPosn, uncompressedLen;
FILE* inputFp = NULL;
unsigned long crc;
time_t modWhen;
if (mReadOnly)
return INVALID_OPERATION;
assert(compressionMethod == ZipEntry::kCompressDeflated ||
compressionMethod == ZipEntry::kCompressStored);
/* make sure we're in a reasonable state */
assert(mZipFp != NULL);
assert(mEntries.size() == mEOCD.mTotalNumEntries);
/* make sure it doesn't already exist */
if (getEntryByName(storageName) != NULL)
return ALREADY_EXISTS;
if (!data) {
inputFp = fopen(fileName, FILE_OPEN_RO);
if (inputFp == NULL)
return errnoToStatus(errno);
}
if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
result = UNKNOWN_ERROR;
goto bail;
}
pEntry = new ZipEntry;
pEntry->initNew(storageName, NULL);
/*
* From here on out, failures are more interesting.
*/
mNeedCDRewrite = true;
/*
* Write the LFH, even though it's still mostly blank. We need it
* as a place-holder. In theory the LFH isn't necessary, but in
* practice some utilities demand it.
*/
lfhPosn = ftell(mZipFp);
pEntry->mLFH.write(mZipFp);
startPosn = ftell(mZipFp);
/*
* Copy the data in, possibly compressing it as we go.
*/
if (sourceType == ZipEntry::kCompressStored) {
if (compressionMethod == ZipEntry::kCompressDeflated) {
bool failed = false;
result = compressFpToFp(mZipFp, inputFp, data, size, &crc);
if (result != NO_ERROR) {
ALOGD("compression failed, storing\n");
failed = true;
} else {
/*
* Make sure it has compressed "enough". This probably ought
* to be set through an API call, but I don't expect our
* criteria to change over time.
*/
long src = inputFp ? ftell(inputFp) : size;
long dst = ftell(mZipFp) - startPosn;
if (dst + (dst / 10) > src) {
ALOGD("insufficient compression (src=%ld dst=%ld), storing\n",
src, dst);
failed = true;
}
}
if (failed) {
compressionMethod = ZipEntry::kCompressStored;
if (inputFp) rewind(inputFp);
fseek(mZipFp, startPosn, SEEK_SET);
/* fall through to kCompressStored case */
}
}
/* handle "no compression" request, or failed compression from above */
if (compressionMethod == ZipEntry::kCompressStored) {
if (inputFp) {
result = copyFpToFp(mZipFp, inputFp, &crc);
} else {
result = copyDataToFp(mZipFp, data, size, &crc);
}
if (result != NO_ERROR) {
// don't need to truncate; happens in CDE rewrite
ALOGD("failed copying data in\n");
goto bail;
}
}
// currently seeked to end of file
uncompressedLen = inputFp ? ftell(inputFp) : size;
} else if (sourceType == ZipEntry::kCompressDeflated) {
/* we should support uncompressed-from-compressed, but it's not
* important right now */
assert(compressionMethod == ZipEntry::kCompressDeflated);
bool scanResult;
int method;
long compressedLen;
scanResult = ZipUtils::examineGzip(inputFp, &method, &uncompressedLen,
&compressedLen, &crc);
if (!scanResult || method != ZipEntry::kCompressDeflated) {
ALOGD("this isn't a deflated gzip file?");
result = UNKNOWN_ERROR;
goto bail;
}
result = copyPartialFpToFp(mZipFp, inputFp, compressedLen, NULL);
if (result != NO_ERROR) {
ALOGD("failed copying gzip data in\n");
goto bail;
}
} else {
assert(false);
result = UNKNOWN_ERROR;
goto bail;
}
/*
* We could write the "Data Descriptor", but there doesn't seem to
* be any point since we're going to go back and write the LFH.
*
* Update file offsets.
*/
endPosn = ftell(mZipFp); // seeked to end of compressed data
/*
* Success! Fill out new values.
*/
pEntry->setDataInfo(uncompressedLen, endPosn - startPosn, crc,
compressionMethod);
modWhen = getModTime(inputFp ? fileno(inputFp) : fileno(mZipFp));
pEntry->setModWhen(modWhen);
pEntry->setLFHOffset(lfhPosn);
mEOCD.mNumEntries++;
mEOCD.mTotalNumEntries++;
mEOCD.mCentralDirSize = 0; // mark invalid; set by flush()
mEOCD.mCentralDirOffset = endPosn;
/*
* Go back and write the LFH.
*/
if (fseek(mZipFp, lfhPosn, SEEK_SET) != 0) {
result = UNKNOWN_ERROR;
goto bail;
}
pEntry->mLFH.write(mZipFp);
/*
* Add pEntry to the list.
*/
mEntries.add(pEntry);
if (ppEntry != NULL)
*ppEntry = pEntry;
pEntry = NULL;
bail:
if (inputFp != NULL)
fclose(inputFp);
delete pEntry;
return result;
}
/*
* Add an entry by copying it from another zip file. If "padding" is
* nonzero, the specified number of bytes will be added to the "extra"
* field in the header.
*
* If "ppEntry" is non-NULL, a pointer to the new entry will be returned.
*/
status_t ZipFile::add(const ZipFile* pSourceZip, const ZipEntry* pSourceEntry,
int padding, ZipEntry** ppEntry)
{
ZipEntry* pEntry = NULL;
status_t result;
long lfhPosn, endPosn;
if (mReadOnly)
return INVALID_OPERATION;
/* make sure we're in a reasonable state */
assert(mZipFp != NULL);
assert(mEntries.size() == mEOCD.mTotalNumEntries);
if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0) {
result = UNKNOWN_ERROR;
goto bail;
}
pEntry = new ZipEntry;
if (pEntry == NULL) {
result = NO_MEMORY;
goto bail;
}
result = pEntry->initFromExternal(pSourceZip, pSourceEntry);
if (result != NO_ERROR)
goto bail;
if (padding != 0) {
result = pEntry->addPadding(padding);
if (result != NO_ERROR)
goto bail;
}
/*
* From here on out, failures are more interesting.
*/
mNeedCDRewrite = true;
/*
* Write the LFH. Since we're not recompressing the data, we already
* have all of the fields filled out.
*/
lfhPosn = ftell(mZipFp);
pEntry->mLFH.write(mZipFp);
/*
* Copy the data over.
*
* If the "has data descriptor" flag is set, we want to copy the DD
* fields as well. This is a fixed-size area immediately following
* the data.
*/
if (fseek(pSourceZip->mZipFp, pSourceEntry->getFileOffset(), SEEK_SET) != 0)
{
result = UNKNOWN_ERROR;
goto bail;
}
off_t copyLen;
copyLen = pSourceEntry->getCompressedLen();
if ((pSourceEntry->mLFH.mGPBitFlag & ZipEntry::kUsesDataDescr) != 0)
copyLen += ZipEntry::kDataDescriptorLen;
if (copyPartialFpToFp(mZipFp, pSourceZip->mZipFp, copyLen, NULL)
!= NO_ERROR)
{
ALOGW("copy of '%s' failed\n", pEntry->mCDE.mFileName);
result = UNKNOWN_ERROR;
goto bail;
}
/*
* Update file offsets.
*/
endPosn = ftell(mZipFp);
/*
* Success! Fill out new values.
*/
pEntry->setLFHOffset(lfhPosn); // sets mCDE.mLocalHeaderRelOffset
mEOCD.mNumEntries++;
mEOCD.mTotalNumEntries++;
mEOCD.mCentralDirSize = 0; // mark invalid; set by flush()
mEOCD.mCentralDirOffset = endPosn;
/*
* Add pEntry to the list.
*/
mEntries.add(pEntry);
if (ppEntry != NULL)
*ppEntry = pEntry;
pEntry = NULL;
result = NO_ERROR;
bail:
delete pEntry;
return result;
}
/*
* Copy all of the bytes in "src" to "dst".
*
* On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
* will be seeked immediately past the data.
*/
status_t ZipFile::copyFpToFp(FILE* dstFp, FILE* srcFp, unsigned long* pCRC32)
{
unsigned char tmpBuf[32768];
size_t count;
*pCRC32 = crc32(0L, Z_NULL, 0);
while (1) {
count = fread(tmpBuf, 1, sizeof(tmpBuf), srcFp);
if (ferror(srcFp) || ferror(dstFp))
return errnoToStatus(errno);
if (count == 0)
break;
*pCRC32 = crc32(*pCRC32, tmpBuf, count);
if (fwrite(tmpBuf, 1, count, dstFp) != count) {
ALOGD("fwrite %d bytes failed\n", (int) count);
return UNKNOWN_ERROR;
}
}
return NO_ERROR;
}
/*
* Copy all of the bytes in "src" to "dst".
*
* On exit, "dstFp" will be seeked immediately past the data.
*/
status_t ZipFile::copyDataToFp(FILE* dstFp,
const void* data, size_t size, unsigned long* pCRC32)
{
size_t count;
*pCRC32 = crc32(0L, Z_NULL, 0);
if (size > 0) {
*pCRC32 = crc32(*pCRC32, (const unsigned char*)data, size);
if (fwrite(data, 1, size, dstFp) != size) {
ALOGD("fwrite %d bytes failed\n", (int) size);
return UNKNOWN_ERROR;
}
}
return NO_ERROR;
}
/*
* Copy some of the bytes in "src" to "dst".
*
* If "pCRC32" is NULL, the CRC will not be computed.
*
* On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
* will be seeked immediately past the data just written.
*/
status_t ZipFile::copyPartialFpToFp(FILE* dstFp, FILE* srcFp, long length,
unsigned long* pCRC32)
{
unsigned char tmpBuf[32768];
size_t count;
if (pCRC32 != NULL)
*pCRC32 = crc32(0L, Z_NULL, 0);
while (length) {
long readSize;
readSize = sizeof(tmpBuf);
if (readSize > length)
readSize = length;
count = fread(tmpBuf, 1, readSize, srcFp);
if ((long) count != readSize) { // error or unexpected EOF
ALOGD("fread %d bytes failed\n", (int) readSize);
return UNKNOWN_ERROR;
}
if (pCRC32 != NULL)
*pCRC32 = crc32(*pCRC32, tmpBuf, count);
if (fwrite(tmpBuf, 1, count, dstFp) != count) {
ALOGD("fwrite %d bytes failed\n", (int) count);
return UNKNOWN_ERROR;
}
length -= readSize;
}
return NO_ERROR;
}
/*
* Compress all of the data in "srcFp" and write it to "dstFp".
*
* On exit, "srcFp" will be seeked to the end of the file, and "dstFp"
* will be seeked immediately past the compressed data.
*/
status_t ZipFile::compressFpToFp(FILE* dstFp, FILE* srcFp,
const void* data, size_t size, unsigned long* pCRC32)
{
status_t result = NO_ERROR;
const size_t kBufSize = 32768;
unsigned char* inBuf = NULL;
unsigned char* outBuf = NULL;
z_stream zstream;
bool atEof = false; // no feof() aviailable yet
unsigned long crc;
int zerr;
/*
* Create an input buffer and an output buffer.
*/
inBuf = new unsigned char[kBufSize];
outBuf = new unsigned char[kBufSize];
if (inBuf == NULL || outBuf == NULL) {
result = NO_MEMORY;
goto bail;
}
/*
* Initialize the zlib stream.
*/
memset(&zstream, 0, sizeof(zstream));
zstream.zalloc = Z_NULL;
zstream.zfree = Z_NULL;
zstream.opaque = Z_NULL;
zstream.next_in = NULL;
zstream.avail_in = 0;
zstream.next_out = outBuf;
zstream.avail_out = kBufSize;
zstream.data_type = Z_UNKNOWN;
zerr = deflateInit2(&zstream, Z_BEST_COMPRESSION,
Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY);
if (zerr != Z_OK) {
result = UNKNOWN_ERROR;
if (zerr == Z_VERSION_ERROR) {
ALOGE("Installed zlib is not compatible with linked version (%s)\n",
ZLIB_VERSION);
} else {
ALOGD("Call to deflateInit2 failed (zerr=%d)\n", zerr);
}
goto bail;
}
crc = crc32(0L, Z_NULL, 0);
/*
* Loop while we have data.
*/
do {
size_t getSize;
int flush;
/* only read if the input buffer is empty */
if (zstream.avail_in == 0 && !atEof) {
ALOGV("+++ reading %d bytes\n", (int)kBufSize);
if (data) {
getSize = size > kBufSize ? kBufSize : size;
memcpy(inBuf, data, getSize);
data = ((const char*)data) + getSize;
size -= getSize;
} else {
getSize = fread(inBuf, 1, kBufSize, srcFp);
if (ferror(srcFp)) {
ALOGD("deflate read failed (errno=%d)\n", errno);
goto z_bail;
}
}
if (getSize < kBufSize) {
ALOGV("+++ got %d bytes, EOF reached\n",
(int)getSize);
atEof = true;
}
crc = crc32(crc, inBuf, getSize);
zstream.next_in = inBuf;
zstream.avail_in = getSize;
}
if (atEof)
flush = Z_FINISH; /* tell zlib that we're done */
else
flush = Z_NO_FLUSH; /* more to come! */
zerr = deflate(&zstream, flush);
if (zerr != Z_OK && zerr != Z_STREAM_END) {
ALOGD("zlib deflate call failed (zerr=%d)\n", zerr);
result = UNKNOWN_ERROR;
goto z_bail;
}
/* write when we're full or when we're done */
if (zstream.avail_out == 0 ||
(zerr == Z_STREAM_END && zstream.avail_out != (uInt) kBufSize))
{
ALOGV("+++ writing %d bytes\n", (int) (zstream.next_out - outBuf));
if (fwrite(outBuf, 1, zstream.next_out - outBuf, dstFp) !=
(size_t)(zstream.next_out - outBuf))
{
ALOGD("write %d failed in deflate\n",
(int) (zstream.next_out - outBuf));
goto z_bail;
}
zstream.next_out = outBuf;
zstream.avail_out = kBufSize;
}
} while (zerr == Z_OK);
assert(zerr == Z_STREAM_END); /* other errors should've been caught */
*pCRC32 = crc;
z_bail:
deflateEnd(&zstream); /* free up any allocated structures */
bail:
delete[] inBuf;
delete[] outBuf;
return result;
}
/*
* Mark an entry as deleted.
*
* We will eventually need to crunch the file down, but if several files
* are being removed (perhaps as part of an "update" process) we can make
* things considerably faster by deferring the removal to "flush" time.
*/
status_t ZipFile::remove(ZipEntry* pEntry)
{
/*
* Should verify that pEntry is actually part of this archive, and
* not some stray ZipEntry from a different file.
*/
/* mark entry as deleted, and mark archive as dirty */
pEntry->setDeleted();
mNeedCDRewrite = true;
return NO_ERROR;
}
/*
* Flush any pending writes.
*
* In particular, this will crunch out deleted entries, and write the
* Central Directory and EOCD if we have stomped on them.
*/
status_t ZipFile::flush(void)
{
status_t result = NO_ERROR;
long eocdPosn;
int i, count;
if (mReadOnly)
return INVALID_OPERATION;
if (!mNeedCDRewrite)
return NO_ERROR;
assert(mZipFp != NULL);
result = crunchArchive();
if (result != NO_ERROR)
return result;
if (fseek(mZipFp, mEOCD.mCentralDirOffset, SEEK_SET) != 0)
return UNKNOWN_ERROR;
count = mEntries.size();
for (i = 0; i < count; i++) {
ZipEntry* pEntry = mEntries[i];
pEntry->mCDE.write(mZipFp);
}
eocdPosn = ftell(mZipFp);
mEOCD.mCentralDirSize = eocdPosn - mEOCD.mCentralDirOffset;
mEOCD.write(mZipFp);
/*
* If we had some stuff bloat up during compression and get replaced
* with plain files, or if we deleted some entries, there's a lot
* of wasted space at the end of the file. Remove it now.
*/
if (ftruncate(fileno(mZipFp), ftell(mZipFp)) != 0) {
ALOGW("ftruncate failed %ld: %s\n", ftell(mZipFp), strerror(errno));
// not fatal
}
/* should we clear the "newly added" flag in all entries now? */
mNeedCDRewrite = false;
return NO_ERROR;
}
/*
* Crunch deleted files out of an archive by shifting the later files down.
*
* Because we're not using a temp file, we do the operation inside the
* current file.
*/
status_t ZipFile::crunchArchive(void)
{
status_t result = NO_ERROR;
int i, count;
long delCount, adjust;
#if 0
printf("CONTENTS:\n");
for (i = 0; i < (int) mEntries.size(); i++) {
printf(" %d: lfhOff=%ld del=%d\n",
i, mEntries[i]->getLFHOffset(), mEntries[i]->getDeleted());
}
printf(" END is %ld\n", (long) mEOCD.mCentralDirOffset);
#endif
/*
* Roll through the set of files, shifting them as appropriate. We
* could probably get a slight performance improvement by sliding
* multiple files down at once (because we could use larger reads
* when operating on batches of small files), but it's not that useful.
*/
count = mEntries.size();
delCount = adjust = 0;
for (i = 0; i < count; i++) {
ZipEntry* pEntry = mEntries[i];
long span;
if (pEntry->getLFHOffset() != 0) {
long nextOffset;
/* Get the length of this entry by finding the offset
* of the next entry. Directory entries don't have
* file offsets, so we need to find the next non-directory
* entry.
*/
nextOffset = 0;
for (int ii = i+1; nextOffset == 0 && ii < count; ii++)
nextOffset = mEntries[ii]->getLFHOffset();
if (nextOffset == 0)
nextOffset = mEOCD.mCentralDirOffset;
span = nextOffset - pEntry->getLFHOffset();
assert(span >= ZipEntry::LocalFileHeader::kLFHLen);
} else {
/* This is a directory entry. It doesn't have
* any actual file contents, so there's no need to
* move anything.
*/
span = 0;
}
//printf("+++ %d: off=%ld span=%ld del=%d [count=%d]\n",
// i, pEntry->getLFHOffset(), span, pEntry->getDeleted(), count);
if (pEntry->getDeleted()) {
adjust += span;
delCount++;
delete pEntry;
mEntries.removeAt(i);
/* adjust loop control */
count--;
i--;
} else if (span != 0 && adjust > 0) {
/* shuffle this entry back */
//printf("+++ Shuffling '%s' back %ld\n",
// pEntry->getFileName(), adjust);
result = filemove(mZipFp, pEntry->getLFHOffset() - adjust,
pEntry->getLFHOffset(), span);
if (result != NO_ERROR) {
/* this is why you use a temp file */
ALOGE("error during crunch - archive is toast\n");
return result;
}
pEntry->setLFHOffset(pEntry->getLFHOffset() - adjust);
}
}
/*
* Fix EOCD info. We have to wait until the end to do some of this
* because we use mCentralDirOffset to determine "span" for the
* last entry.
*/
mEOCD.mCentralDirOffset -= adjust;
mEOCD.mNumEntries -= delCount;
mEOCD.mTotalNumEntries -= delCount;
mEOCD.mCentralDirSize = 0; // mark invalid; set by flush()
assert(mEOCD.mNumEntries == mEOCD.mTotalNumEntries);
assert(mEOCD.mNumEntries == count);
return result;
}
/*
* Works like memmove(), but on pieces of a file.
*/
status_t ZipFile::filemove(FILE* fp, off_t dst, off_t src, size_t n)
{
if (dst == src || n <= 0)
return NO_ERROR;
unsigned char readBuf[32768];
if (dst < src) {
/* shift stuff toward start of file; must read from start */
while (n != 0) {
size_t getSize = sizeof(readBuf);
if (getSize > n)
getSize = n;
if (fseek(fp, (long) src, SEEK_SET) != 0) {
ALOGD("filemove src seek %ld failed\n", (long) src);
return UNKNOWN_ERROR;
}
if (fread(readBuf, 1, getSize, fp) != getSize) {
ALOGD("filemove read %ld off=%ld failed\n",
(long) getSize, (long) src);
return UNKNOWN_ERROR;
}
if (fseek(fp, (long) dst, SEEK_SET) != 0) {
ALOGD("filemove dst seek %ld failed\n", (long) dst);
return UNKNOWN_ERROR;
}
if (fwrite(readBuf, 1, getSize, fp) != getSize) {
ALOGD("filemove write %ld off=%ld failed\n",
(long) getSize, (long) dst);
return UNKNOWN_ERROR;
}
src += getSize;
dst += getSize;
n -= getSize;
}
} else {
/* shift stuff toward end of file; must read from end */
assert(false); // write this someday, maybe
return UNKNOWN_ERROR;
}
return NO_ERROR;
}
/*
* Get the modification time from a file descriptor.
*/
time_t ZipFile::getModTime(int fd)
{
struct stat sb;
if (fstat(fd, &sb) < 0) {
ALOGD("HEY: fstat on fd %d failed\n", fd);
return (time_t) -1;
}
return sb.st_mtime;
}
#if 0 /* this is a bad idea */
/*
* Get a copy of the Zip file descriptor.
*
* We don't allow this if the file was opened read-write because we tend
* to leave the file contents in an uncertain state between calls to
* flush(). The duplicated file descriptor should only be valid for reads.
*/
int ZipFile::getZipFd(void) const
{
if (!mReadOnly)
return INVALID_OPERATION;
assert(mZipFp != NULL);
int fd;
fd = dup(fileno(mZipFp));
if (fd < 0) {
ALOGD("didn't work, errno=%d\n", errno);
}
return fd;
}
#endif
#if 0
/*
* Expand data.
*/
bool ZipFile::uncompress(const ZipEntry* pEntry, void* buf) const
{
return false;
}
#endif
// free the memory when you're done
void* ZipFile::uncompress(const ZipEntry* entry)
{
size_t unlen = entry->getUncompressedLen();
size_t clen = entry->getCompressedLen();
void* buf = malloc(unlen);
if (buf == NULL) {
return NULL;
}
fseek(mZipFp, 0, SEEK_SET);
off_t offset = entry->getFileOffset();
if (fseek(mZipFp, offset, SEEK_SET) != 0) {
goto bail;
}
switch (entry->getCompressionMethod())
{
case ZipEntry::kCompressStored: {
ssize_t amt = fread(buf, 1, unlen, mZipFp);
if (amt != (ssize_t)unlen) {
goto bail;
}
#if 0
printf("data...\n");
const unsigned char* p = (unsigned char*)buf;
const unsigned char* end = p+unlen;
for (int i=0; i<32 && p < end; i++) {
printf("0x%08x ", (int)(offset+(i*0x10)));
for (int j=0; j<0x10 && p < end; j++) {
printf(" %02x", *p);
p++;
}
printf("\n");
}
#endif
}
break;
case ZipEntry::kCompressDeflated: {
if (!ZipUtils::inflateToBuffer(mZipFp, buf, unlen, clen)) {
goto bail;
}
}
break;
default:
goto bail;
}
return buf;
bail:
free(buf);
return NULL;
}
/*
* ===========================================================================
* ZipFile::EndOfCentralDir
* ===========================================================================
*/
/*
* Read the end-of-central-dir fields.
*
* "buf" should be positioned at the EOCD signature, and should contain
* the entire EOCD area including the comment.
*/
status_t ZipFile::EndOfCentralDir::readBuf(const unsigned char* buf, int len)
{
/* don't allow re-use */
assert(mComment == NULL);
if (len < kEOCDLen) {
/* looks like ZIP file got truncated */
ALOGD(" Zip EOCD: expected >= %d bytes, found %d\n",
kEOCDLen, len);
return INVALID_OPERATION;
}
/* this should probably be an assert() */
if (ZipEntry::getLongLE(&buf[0x00]) != kSignature)
return UNKNOWN_ERROR;
mDiskNumber = ZipEntry::getShortLE(&buf[0x04]);
mDiskWithCentralDir = ZipEntry::getShortLE(&buf[0x06]);
mNumEntries = ZipEntry::getShortLE(&buf[0x08]);
mTotalNumEntries = ZipEntry::getShortLE(&buf[0x0a]);
mCentralDirSize = ZipEntry::getLongLE(&buf[0x0c]);
mCentralDirOffset = ZipEntry::getLongLE(&buf[0x10]);
mCommentLen = ZipEntry::getShortLE(&buf[0x14]);
// TODO: validate mCentralDirOffset
if (mCommentLen > 0) {
if (kEOCDLen + mCommentLen > len) {
ALOGD("EOCD(%d) + comment(%d) exceeds len (%d)\n",
kEOCDLen, mCommentLen, len);
return UNKNOWN_ERROR;
}
mComment = new unsigned char[mCommentLen];
memcpy(mComment, buf + kEOCDLen, mCommentLen);
}
return NO_ERROR;
}
/*
* Write an end-of-central-directory section.
*/
status_t ZipFile::EndOfCentralDir::write(FILE* fp)
{
unsigned char buf[kEOCDLen];
ZipEntry::putLongLE(&buf[0x00], kSignature);
ZipEntry::putShortLE(&buf[0x04], mDiskNumber);
ZipEntry::putShortLE(&buf[0x06], mDiskWithCentralDir);
ZipEntry::putShortLE(&buf[0x08], mNumEntries);
ZipEntry::putShortLE(&buf[0x0a], mTotalNumEntries);
ZipEntry::putLongLE(&buf[0x0c], mCentralDirSize);
ZipEntry::putLongLE(&buf[0x10], mCentralDirOffset);
ZipEntry::putShortLE(&buf[0x14], mCommentLen);
if (fwrite(buf, 1, kEOCDLen, fp) != kEOCDLen)
return UNKNOWN_ERROR;
if (mCommentLen > 0) {
assert(mComment != NULL);
if (fwrite(mComment, mCommentLen, 1, fp) != mCommentLen)
return UNKNOWN_ERROR;
}
return NO_ERROR;
}
/*
* Dump the contents of an EndOfCentralDir object.
*/
void ZipFile::EndOfCentralDir::dump(void) const
{
ALOGD(" EndOfCentralDir contents:\n");
ALOGD(" diskNum=%u diskWCD=%u numEnt=%u totalNumEnt=%u\n",
mDiskNumber, mDiskWithCentralDir, mNumEntries, mTotalNumEntries);
ALOGD(" centDirSize=%lu centDirOff=%lu commentLen=%u\n",
mCentralDirSize, mCentralDirOffset, mCommentLen);
}