gecko/netwerk/cache/nsCacheEntryDescriptor.cpp

993 lines
28 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsICache.h"
#include "nsCache.h"
#include "nsCacheService.h"
#include "nsCacheEntryDescriptor.h"
#include "nsCacheEntry.h"
#include "nsReadableUtils.h"
#include "nsIOutputStream.h"
#include "nsCRT.h"
#define kMinDecompressReadBufLen 1024
#define kMinCompressWriteBufLen 1024
NS_IMPL_THREADSAFE_ISUPPORTS2(nsCacheEntryDescriptor,
nsICacheEntryDescriptor,
nsICacheEntryInfo)
nsCacheEntryDescriptor::nsCacheEntryDescriptor(nsCacheEntry * entry,
nsCacheAccessMode accessGranted)
: mCacheEntry(entry),
mAccessGranted(accessGranted),
mOutput(nsnull)
{
PR_INIT_CLIST(this);
NS_ADDREF(nsCacheService::GlobalInstance()); // ensure it lives for the lifetime of the descriptor
}
nsCacheEntryDescriptor::~nsCacheEntryDescriptor()
{
// No need to close if the cache entry has already been severed. This
// helps avoid a shutdown assertion (bug 285519) that is caused when
// consumers end up holding onto these objects past xpcom-shutdown. It's
// okay for them to do that because the cache service calls our Close
// method during xpcom-shutdown, so we don't need to complain about it.
if (mCacheEntry)
Close();
nsCacheService * service = nsCacheService::GlobalInstance();
NS_RELEASE(service);
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetClientID(char ** result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
return ClientIDFromCacheKey(*(mCacheEntry->Key()), result);
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetDeviceID(char ** aDeviceID)
{
NS_ENSURE_ARG_POINTER(aDeviceID);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
const char* deviceID = mCacheEntry->GetDeviceID();
if (!deviceID) {
*aDeviceID = nsnull;
return NS_OK;
}
*aDeviceID = NS_strdup(deviceID);
return *aDeviceID ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetKey(nsACString &result)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
return ClientKeyFromCacheKey(*(mCacheEntry->Key()), result);
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetFetchCount(PRInt32 *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->FetchCount();
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetLastFetched(PRUint32 *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->LastFetched();
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetLastModified(PRUint32 *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->LastModified();
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetExpirationTime(PRUint32 *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->ExpirationTime();
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::SetExpirationTime(PRUint32 expirationTime)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
mCacheEntry->SetExpirationTime(expirationTime);
mCacheEntry->MarkEntryDirty();
return NS_OK;
}
NS_IMETHODIMP nsCacheEntryDescriptor::IsStreamBased(bool *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->IsStreamData();
return NS_OK;
}
NS_IMETHODIMP nsCacheEntryDescriptor::GetPredictedDataSize(PRInt64 *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->PredictedDataSize();
return NS_OK;
}
NS_IMETHODIMP nsCacheEntryDescriptor::SetPredictedDataSize(PRInt64
predictedSize)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
mCacheEntry->SetPredictedDataSize(predictedSize);
return NS_OK;
}
NS_IMETHODIMP nsCacheEntryDescriptor::GetDataSize(PRUint32 *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
const char* val = mCacheEntry->GetMetaDataElement("uncompressed-len");
if (!val) {
*result = mCacheEntry->DataSize();
} else {
*result = atol(val);
}
return NS_OK;
}
NS_IMETHODIMP nsCacheEntryDescriptor::GetStorageDataSize(PRUint32 *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->DataSize();
return NS_OK;
}
nsresult
nsCacheEntryDescriptor::RequestDataSizeChange(PRInt32 deltaSize)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
nsresult rv;
rv = nsCacheService::OnDataSizeChange(mCacheEntry, deltaSize);
if (NS_SUCCEEDED(rv)) {
// XXX review for signed/unsigned math errors
PRUint32 newDataSize = mCacheEntry->DataSize() + deltaSize;
mCacheEntry->SetDataSize(newDataSize);
mCacheEntry->TouchData();
}
return rv;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::SetDataSize(PRUint32 dataSize)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
// XXX review for signed/unsigned math errors
PRInt32 deltaSize = dataSize - mCacheEntry->DataSize();
nsresult rv;
rv = nsCacheService::OnDataSizeChange(mCacheEntry, deltaSize);
// this had better be NS_OK, this call instance is advisory for memory cache objects
if (NS_SUCCEEDED(rv)) {
// XXX review for signed/unsigned math errors
PRUint32 newDataSize = mCacheEntry->DataSize() + deltaSize;
mCacheEntry->SetDataSize(newDataSize);
mCacheEntry->TouchData();
} else {
NS_WARNING("failed SetDataSize() on memory cache object!");
}
return rv;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::OpenInputStream(PRUint32 offset, nsIInputStream ** result)
{
NS_ENSURE_ARG_POINTER(result);
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
if (!mCacheEntry->IsStreamData()) return NS_ERROR_CACHE_DATA_IS_NOT_STREAM;
// ensure valid permissions
if (!(mAccessGranted & nsICache::ACCESS_READ))
return NS_ERROR_CACHE_READ_ACCESS_DENIED;
}
nsInputStreamWrapper* cacheInput = nsnull;
const char *val;
val = mCacheEntry->GetMetaDataElement("uncompressed-len");
if (val) {
cacheInput = new nsDecompressInputStreamWrapper(this, offset);
} else {
cacheInput = new nsInputStreamWrapper(this, offset);
}
if (!cacheInput) return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(*result = cacheInput);
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::OpenOutputStream(PRUint32 offset, nsIOutputStream ** result)
{
NS_ENSURE_ARG_POINTER(result);
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
if (!mCacheEntry->IsStreamData()) return NS_ERROR_CACHE_DATA_IS_NOT_STREAM;
// ensure valid permissions
if (!(mAccessGranted & nsICache::ACCESS_WRITE))
return NS_ERROR_CACHE_WRITE_ACCESS_DENIED;
}
nsOutputStreamWrapper* cacheOutput = nsnull;
PRInt32 compressionLevel = nsCacheService::CacheCompressionLevel();
const char *val;
val = mCacheEntry->GetMetaDataElement("uncompressed-len");
if ((compressionLevel > 0) && val) {
cacheOutput = new nsCompressOutputStreamWrapper(this, offset);
} else {
// clear compression flag when compression disabled - see bug #715198
if (val) {
mCacheEntry->SetMetaDataElement("uncompressed-len", nsnull);
}
cacheOutput = new nsOutputStreamWrapper(this, offset);
}
if (!cacheOutput) return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(*result = cacheOutput);
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetCacheElement(nsISupports ** result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
if (mCacheEntry->IsStreamData()) return NS_ERROR_CACHE_DATA_IS_STREAM;
NS_IF_ADDREF(*result = mCacheEntry->Data());
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::SetCacheElement(nsISupports * cacheElement)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
if (mCacheEntry->IsStreamData()) return NS_ERROR_CACHE_DATA_IS_STREAM;
return nsCacheService::SetCacheElement(mCacheEntry, cacheElement);
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetAccessGranted(nsCacheAccessMode *result)
{
NS_ENSURE_ARG_POINTER(result);
*result = mAccessGranted;
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetStoragePolicy(nsCacheStoragePolicy *result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->StoragePolicy();
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::SetStoragePolicy(nsCacheStoragePolicy policy)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
// XXX validate policy against session?
bool storageEnabled = false;
storageEnabled = nsCacheService::IsStorageEnabledForPolicy_Locked(policy);
if (!storageEnabled) return NS_ERROR_FAILURE;
// Don't change the storage policy of entries we can't write
if (!(mAccessGranted & nsICache::ACCESS_WRITE))
return NS_ERROR_NOT_AVAILABLE;
// Don't allow a cache entry to move from memory-only to anything else
if (mCacheEntry->StoragePolicy() == nsICache::STORE_IN_MEMORY &&
policy != nsICache::STORE_IN_MEMORY)
return NS_ERROR_NOT_AVAILABLE;
mCacheEntry->SetStoragePolicy(policy);
mCacheEntry->MarkEntryDirty();
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetFile(nsIFile ** result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
return nsCacheService::GetFileForEntry(mCacheEntry, result);
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetSecurityInfo(nsISupports ** result)
{
NS_ENSURE_ARG_POINTER(result);
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
*result = mCacheEntry->SecurityInfo();
NS_IF_ADDREF(*result);
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::SetSecurityInfo(nsISupports * securityInfo)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
mCacheEntry->SetSecurityInfo(securityInfo);
mCacheEntry->MarkEntryDirty();
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::Doom()
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
return nsCacheService::DoomEntry(mCacheEntry);
}
NS_IMETHODIMP
nsCacheEntryDescriptor::DoomAndFailPendingRequests(nsresult status)
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::MarkValid()
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
nsresult rv = nsCacheService::ValidateEntry(mCacheEntry);
return rv;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::Close()
{
nsCacheServiceAutoLock lock;
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
// XXX perhaps closing descriptors should clear/sever transports
// tell nsCacheService we're going away
nsCacheService::CloseDescriptor(this);
NS_ASSERTION(mCacheEntry == nsnull, "mCacheEntry not null");
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::GetMetaDataElement(const char *key, char **result)
{
NS_ENSURE_ARG_POINTER(key);
*result = nsnull;
nsCacheServiceAutoLock lock;
NS_ENSURE_TRUE(mCacheEntry, NS_ERROR_NOT_AVAILABLE);
const char *value;
value = mCacheEntry->GetMetaDataElement(key);
if (!value) return NS_ERROR_NOT_AVAILABLE;
*result = NS_strdup(value);
if (!*result) return NS_ERROR_OUT_OF_MEMORY;
return NS_OK;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::SetMetaDataElement(const char *key, const char *value)
{
NS_ENSURE_ARG_POINTER(key);
nsCacheServiceAutoLock lock;
NS_ENSURE_TRUE(mCacheEntry, NS_ERROR_NOT_AVAILABLE);
// XXX allow null value, for clearing key?
nsresult rv = mCacheEntry->SetMetaDataElement(key, value);
if (NS_SUCCEEDED(rv))
mCacheEntry->TouchMetaData();
return rv;
}
NS_IMETHODIMP
nsCacheEntryDescriptor::VisitMetaData(nsICacheMetaDataVisitor * visitor)
{
nsCacheServiceAutoLock lock; // XXX check callers, we're calling out of module
NS_ENSURE_ARG_POINTER(visitor);
if (!mCacheEntry) return NS_ERROR_NOT_AVAILABLE;
return mCacheEntry->VisitMetaDataElements(visitor);
}
/******************************************************************************
* nsCacheInputStream - a wrapper for nsIInputStream keeps the cache entry
* open while referenced.
******************************************************************************/
NS_IMPL_THREADSAFE_ISUPPORTS1(nsCacheEntryDescriptor::nsInputStreamWrapper,
nsIInputStream)
nsresult nsCacheEntryDescriptor::
nsInputStreamWrapper::LazyInit()
{
nsCacheServiceAutoLock lock;
nsCacheAccessMode mode;
nsresult rv = mDescriptor->GetAccessGranted(&mode);
if (NS_FAILED(rv)) return rv;
NS_ENSURE_TRUE(mode & nsICache::ACCESS_READ, NS_ERROR_UNEXPECTED);
nsCacheEntry* cacheEntry = mDescriptor->CacheEntry();
if (!cacheEntry) return NS_ERROR_NOT_AVAILABLE;
rv = nsCacheService::OpenInputStreamForEntry(cacheEntry, mode,
mStartOffset,
getter_AddRefs(mInput));
CACHE_LOG_DEBUG(("nsInputStreamWrapper::LazyInit "
"[entry=%p, wrapper=%p, mInput=%p, rv=%d]",
mDescriptor, this, mInput.get(), PRIntn(rv)));
if (NS_FAILED(rv)) return rv;
mInitialized = true;
return NS_OK;
}
nsresult nsCacheEntryDescriptor::
nsInputStreamWrapper::Close()
{
nsresult rv = EnsureInit();
if (NS_FAILED(rv)) return rv;
return mInput->Close();
}
nsresult nsCacheEntryDescriptor::
nsInputStreamWrapper::Available(PRUint32 *avail)
{
nsresult rv = EnsureInit();
if (NS_FAILED(rv)) return rv;
return mInput->Available(avail);
}
nsresult nsCacheEntryDescriptor::
nsInputStreamWrapper::Read(char *buf, PRUint32 count, PRUint32 *countRead)
{
nsresult rv = EnsureInit();
if (NS_SUCCEEDED(rv))
rv = mInput->Read(buf, count, countRead);
CACHE_LOG_DEBUG(("nsInputStreamWrapper::Read "
"[entry=%p, wrapper=%p, mInput=%p, rv=%d]",
mDescriptor, this, mInput.get(), rv));
return rv;
}
nsresult nsCacheEntryDescriptor::
nsInputStreamWrapper::ReadSegments(nsWriteSegmentFun writer, void *closure,
PRUint32 count, PRUint32 *countRead)
{
// cache stream not buffered
return NS_ERROR_NOT_IMPLEMENTED;
}
nsresult nsCacheEntryDescriptor::
nsInputStreamWrapper::IsNonBlocking(bool *result)
{
// cache streams will never return NS_BASE_STREAM_WOULD_BLOCK
*result = false;
return NS_OK;
}
/******************************************************************************
* nsDecompressInputStreamWrapper - an input stream wrapper that decompresses
******************************************************************************/
NS_IMPL_THREADSAFE_ISUPPORTS1(nsCacheEntryDescriptor::nsDecompressInputStreamWrapper,
nsIInputStream)
NS_IMETHODIMP nsCacheEntryDescriptor::
nsDecompressInputStreamWrapper::Read(char * buf,
PRUint32 count,
PRUint32 *countRead)
{
int zerr = Z_OK;
nsresult rv = NS_OK;
if (!mStreamInitialized) {
rv = InitZstream();
if (NS_FAILED(rv)) {
return rv;
}
}
mZstream.next_out = (Bytef*)buf;
mZstream.avail_out = count;
if (mReadBufferLen < count) {
// Allocate a buffer for reading from the input stream. This will
// determine the max number of compressed bytes read from the
// input stream at one time. Making the buffer size proportional
// to the request size is not necessary, but helps minimize the
// number of read requests to the input stream.
PRUint32 newBufLen = NS_MAX(count, (PRUint32)kMinDecompressReadBufLen);
unsigned char* newBuf;
newBuf = (unsigned char*)nsMemory::Realloc(mReadBuffer,
newBufLen);
if (newBuf) {
mReadBuffer = newBuf;
mReadBufferLen = newBufLen;
}
if (!mReadBuffer) {
mReadBufferLen = 0;
return NS_ERROR_OUT_OF_MEMORY;
}
}
// read and inflate data until the output buffer is full, or
// there is no more data to read
while (NS_SUCCEEDED(rv) &&
zerr == Z_OK &&
mZstream.avail_out > 0 &&
count > 0) {
if (mZstream.avail_in == 0) {
rv = nsInputStreamWrapper::Read((char*)mReadBuffer,
mReadBufferLen,
&mZstream.avail_in);
if (NS_FAILED(rv) || !mZstream.avail_in) {
break;
}
mZstream.next_in = mReadBuffer;
}
zerr = inflate(&mZstream, Z_NO_FLUSH);
if (zerr == Z_STREAM_END) {
// The compressed data may have been stored in multiple
// chunks/streams. To allow for this case, re-initialize
// the inflate stream and continue decompressing from
// the next byte.
Bytef * saveNextIn = mZstream.next_in;
unsigned int saveAvailIn = mZstream.avail_in;
Bytef * saveNextOut = mZstream.next_out;
unsigned int saveAvailOut = mZstream.avail_out;
inflateReset(&mZstream);
mZstream.next_in = saveNextIn;
mZstream.avail_in = saveAvailIn;
mZstream.next_out = saveNextOut;
mZstream.avail_out = saveAvailOut;
zerr = Z_OK;
} else if (zerr != Z_OK) {
rv = NS_ERROR_INVALID_CONTENT_ENCODING;
}
}
if (NS_SUCCEEDED(rv)) {
*countRead = count - mZstream.avail_out;
}
return rv;
}
nsresult nsCacheEntryDescriptor::
nsDecompressInputStreamWrapper::Close()
{
EndZstream();
if (mReadBuffer) {
nsMemory::Free(mReadBuffer);
mReadBuffer = 0;
mReadBufferLen = 0;
}
return nsInputStreamWrapper::Close();
}
nsresult nsCacheEntryDescriptor::
nsDecompressInputStreamWrapper::InitZstream()
{
// Initialize zlib inflate stream
mZstream.zalloc = Z_NULL;
mZstream.zfree = Z_NULL;
mZstream.opaque = Z_NULL;
mZstream.next_out = Z_NULL;
mZstream.avail_out = 0;
mZstream.next_in = Z_NULL;
mZstream.avail_in = 0;
if (inflateInit(&mZstream) != Z_OK) {
return NS_ERROR_FAILURE;
}
mStreamInitialized = true;
return NS_OK;
}
nsresult nsCacheEntryDescriptor::
nsDecompressInputStreamWrapper::EndZstream()
{
if (mStreamInitialized && !mStreamEnded) {
inflateEnd(&mZstream);
mStreamEnded = true;
}
return NS_OK;
}
/******************************************************************************
* nsOutputStreamWrapper - a wrapper for nsIOutputstream to track the amount of
* data written to a cache entry.
* - also keeps the cache entry open while referenced.
******************************************************************************/
NS_IMPL_THREADSAFE_ISUPPORTS1(nsCacheEntryDescriptor::nsOutputStreamWrapper,
nsIOutputStream)
nsresult nsCacheEntryDescriptor::
nsOutputStreamWrapper::LazyInit()
{
nsCacheServiceAutoLock lock;
nsCacheAccessMode mode;
nsresult rv = mDescriptor->GetAccessGranted(&mode);
if (NS_FAILED(rv)) return rv;
NS_ENSURE_TRUE(mode & nsICache::ACCESS_WRITE, NS_ERROR_UNEXPECTED);
nsCacheEntry* cacheEntry = mDescriptor->CacheEntry();
if (!cacheEntry) return NS_ERROR_NOT_AVAILABLE;
NS_ASSERTION(mOutput == nsnull, "mOutput set in LazyInit");
nsCOMPtr<nsIOutputStream> stream;
rv = nsCacheService::OpenOutputStreamForEntry(cacheEntry, mode, mStartOffset,
getter_AddRefs(stream));
if (NS_FAILED(rv))
return rv;
nsCacheDevice* device = cacheEntry->CacheDevice();
if (device) {
// the entry has been truncated to mStartOffset bytes, inform device
PRInt32 size = cacheEntry->DataSize();
rv = device->OnDataSizeChange(cacheEntry, mStartOffset - size);
if (NS_SUCCEEDED(rv))
cacheEntry->SetDataSize(mStartOffset);
} else {
rv = NS_ERROR_NOT_AVAILABLE;
}
// If anything above failed, clean up internal state and get out of here
// (see bug #654926)...
if (NS_FAILED(rv)) {
mDescriptor->InternalCleanup(stream);
return rv;
}
// ... otherwise, set members and mark initialized
mDescriptor->mOutput = mOutput = stream;
mInitialized = true;
return NS_OK;
}
nsresult nsCacheEntryDescriptor::
nsOutputStreamWrapper::OnWrite(PRUint32 count)
{
if (count > PR_INT32_MAX) return NS_ERROR_UNEXPECTED;
return mDescriptor->RequestDataSizeChange((PRInt32)count);
}
NS_IMETHODIMP nsCacheEntryDescriptor::
nsOutputStreamWrapper::Close()
{
nsresult rv = EnsureInit();
if (NS_FAILED(rv)) return rv;
return mOutput->Close();
}
NS_IMETHODIMP nsCacheEntryDescriptor::
nsOutputStreamWrapper::Flush()
{
nsresult rv = EnsureInit();
if (NS_FAILED(rv)) return rv;
return mOutput->Flush();
}
NS_IMETHODIMP nsCacheEntryDescriptor::
nsOutputStreamWrapper::Write(const char * buf,
PRUint32 count,
PRUint32 * result)
{
nsresult rv = EnsureInit();
if (NS_FAILED(rv)) return rv;
rv = OnWrite(count);
if (NS_FAILED(rv)) return rv;
return mOutput->Write(buf, count, result);
}
NS_IMETHODIMP nsCacheEntryDescriptor::
nsOutputStreamWrapper::WriteFrom(nsIInputStream * inStr,
PRUint32 count,
PRUint32 * result)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP nsCacheEntryDescriptor::
nsOutputStreamWrapper::WriteSegments(nsReadSegmentFun reader,
void * closure,
PRUint32 count,
PRUint32 * result)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP nsCacheEntryDescriptor::
nsOutputStreamWrapper::IsNonBlocking(bool *result)
{
// cache streams will never return NS_BASE_STREAM_WOULD_BLOCK
*result = false;
return NS_OK;
}
/******************************************************************************
* nsCompressOutputStreamWrapper - an output stream wrapper that compresses
* data before it is written
******************************************************************************/
NS_IMPL_THREADSAFE_ISUPPORTS1(nsCacheEntryDescriptor::nsCompressOutputStreamWrapper,
nsIOutputStream)
NS_IMETHODIMP nsCacheEntryDescriptor::
nsCompressOutputStreamWrapper::Write(const char * buf,
PRUint32 count,
PRUint32 * result)
{
int zerr = Z_OK;
nsresult rv = NS_OK;
if (!mStreamInitialized) {
rv = InitZstream();
if (NS_FAILED(rv)) {
return rv;
}
}
if (!mWriteBuffer) {
// Once allocated, this buffer is referenced by the zlib stream and
// cannot be grown. We use 2x(initial write request) to approximate
// a stream buffer size proportional to request buffers.
mWriteBufferLen = NS_MAX(count*2, (PRUint32)kMinCompressWriteBufLen);
mWriteBuffer = (unsigned char*)nsMemory::Alloc(mWriteBufferLen);
if (!mWriteBuffer) {
mWriteBufferLen = 0;
return NS_ERROR_OUT_OF_MEMORY;
}
mZstream.next_out = mWriteBuffer;
mZstream.avail_out = mWriteBufferLen;
}
// Compress (deflate) the requested buffer. Keep going
// until the entire buffer has been deflated.
mZstream.avail_in = count;
mZstream.next_in = (Bytef*)buf;
while (mZstream.avail_in > 0) {
zerr = deflate(&mZstream, Z_NO_FLUSH);
if (zerr == Z_STREAM_ERROR) {
deflateEnd(&mZstream);
mStreamInitialized = false;
return NS_ERROR_FAILURE;
}
// Note: Z_BUF_ERROR is non-fatal and sometimes expected here.
// If the compression stream output buffer is filled, write
// it out to the underlying stream wrapper.
if (mZstream.avail_out == 0) {
rv = WriteBuffer();
if (NS_FAILED(rv)) {
deflateEnd(&mZstream);
mStreamInitialized = false;
return rv;
}
}
}
*result = count;
mUncompressedCount += *result;
return NS_OK;
}
NS_IMETHODIMP nsCacheEntryDescriptor::
nsCompressOutputStreamWrapper::Close()
{
nsresult rv = NS_OK;
int zerr = 0;
if (mStreamInitialized) {
// complete compression of any data remaining in the zlib stream
do {
zerr = deflate(&mZstream, Z_FINISH);
rv = WriteBuffer();
} while (zerr == Z_OK && rv == NS_OK);
deflateEnd(&mZstream);
}
if (mDescriptor->CacheEntry()) {
nsCAutoString uncompressedLenStr;
rv = mDescriptor->GetMetaDataElement("uncompressed-len",
getter_Copies(uncompressedLenStr));
if (NS_SUCCEEDED(rv)) {
PRInt32 oldCount = uncompressedLenStr.ToInteger(&rv);
if (NS_SUCCEEDED(rv)) {
mUncompressedCount += oldCount;
}
}
uncompressedLenStr.Adopt(0);
uncompressedLenStr.AppendInt(mUncompressedCount);
rv = mDescriptor->SetMetaDataElement("uncompressed-len",
uncompressedLenStr.get());
}
if (mWriteBuffer) {
nsMemory::Free(mWriteBuffer);
mWriteBuffer = 0;
mWriteBufferLen = 0;
}
return nsOutputStreamWrapper::Close();
}
nsresult nsCacheEntryDescriptor::
nsCompressOutputStreamWrapper::InitZstream()
{
// Determine compression level: Aggressive compression
// may impact performance on mobile devices, while a
// lower compression level still provides substantial
// space savings for many text streams.
PRInt32 compressionLevel = nsCacheService::CacheCompressionLevel();
// Initialize zlib deflate stream
mZstream.zalloc = Z_NULL;
mZstream.zfree = Z_NULL;
mZstream.opaque = Z_NULL;
if (deflateInit2(&mZstream, compressionLevel, Z_DEFLATED,
MAX_WBITS, 8, Z_DEFAULT_STRATEGY) != Z_OK) {
return NS_ERROR_FAILURE;
}
mZstream.next_in = Z_NULL;
mZstream.avail_in = 0;
mStreamInitialized = true;
return NS_OK;
}
nsresult nsCacheEntryDescriptor::
nsCompressOutputStreamWrapper::WriteBuffer()
{
PRUint32 bytesToWrite = mWriteBufferLen - mZstream.avail_out;
PRUint32 result = 0;
nsresult rv = nsCacheEntryDescriptor::nsOutputStreamWrapper::Write(
(const char *)mWriteBuffer, bytesToWrite, &result);
mZstream.next_out = mWriteBuffer;
mZstream.avail_out = mWriteBufferLen;
return rv;
}