gecko-dev/netwerk/base/nsIncrementalStreamLoader.cpp

214 строки
6.1 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 "nsIncrementalStreamLoader.h"
#include "nsIInputStream.h"
#include "nsIChannel.h"
#include "nsError.h"
#include "GeckoProfiler.h"
#include <limits>
nsIncrementalStreamLoader::nsIncrementalStreamLoader()
: mData(), mBytesConsumed(0)
{
}
nsIncrementalStreamLoader::~nsIncrementalStreamLoader()
{
}
NS_IMETHODIMP
nsIncrementalStreamLoader::Init(nsIIncrementalStreamLoaderObserver* observer)
{
NS_ENSURE_ARG_POINTER(observer);
mObserver = observer;
return NS_OK;
}
nsresult
nsIncrementalStreamLoader::Create(nsISupports *aOuter, REFNSIID aIID, void **aResult)
{
if (aOuter) return NS_ERROR_NO_AGGREGATION;
nsIncrementalStreamLoader* it = new nsIncrementalStreamLoader();
if (it == nullptr)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(it);
nsresult rv = it->QueryInterface(aIID, aResult);
NS_RELEASE(it);
return rv;
}
NS_IMPL_ISUPPORTS(nsIncrementalStreamLoader, nsIIncrementalStreamLoader,
nsIRequestObserver, nsIStreamListener,
nsIThreadRetargetableStreamListener)
NS_IMETHODIMP
nsIncrementalStreamLoader::GetNumBytesRead(uint32_t* aNumBytes)
{
*aNumBytes = mBytesConsumed + mData.length();
return NS_OK;
}
/* readonly attribute nsIRequest request; */
NS_IMETHODIMP
nsIncrementalStreamLoader::GetRequest(nsIRequest **aRequest)
{
NS_IF_ADDREF(*aRequest = mRequest);
return NS_OK;
}
NS_IMETHODIMP
nsIncrementalStreamLoader::OnStartRequest(nsIRequest* request, nsISupports *ctxt)
{
nsCOMPtr<nsIChannel> chan( do_QueryInterface(request) );
if (chan) {
int64_t contentLength = -1;
chan->GetContentLength(&contentLength);
if (contentLength >= 0) {
if (uint64_t(contentLength) > std::numeric_limits<size_t>::max()) {
// Too big to fit into size_t, so let's bail.
return NS_ERROR_OUT_OF_MEMORY;
}
// preallocate buffer
if (!mData.initCapacity(contentLength)) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
}
mContext = ctxt;
return NS_OK;
}
NS_IMETHODIMP
nsIncrementalStreamLoader::OnStopRequest(nsIRequest* request, nsISupports *ctxt,
nsresult aStatus)
{
AUTO_PROFILER_LABEL("nsIncrementalStreamLoader::OnStopRequest", NETWORK);
if (mObserver) {
// provide nsIIncrementalStreamLoader::request during call to OnStreamComplete
mRequest = request;
size_t length = mData.length();
uint8_t* elems = mData.extractOrCopyRawBuffer();
nsresult rv = mObserver->OnStreamComplete(this, mContext, aStatus,
length, elems);
if (rv != NS_SUCCESS_ADOPTED_DATA) {
// The observer didn't take ownership of the extracted data buffer, so
// put it back into mData.
mData.replaceRawBuffer(elems, length);
}
// done.. cleanup
ReleaseData();
mRequest = nullptr;
mObserver = nullptr;
mContext = nullptr;
}
return NS_OK;
}
nsresult
nsIncrementalStreamLoader::WriteSegmentFun(nsIInputStream *inStr,
void *closure,
const char *fromSegment,
uint32_t toOffset,
uint32_t count,
uint32_t *writeCount)
{
nsIncrementalStreamLoader *self = (nsIncrementalStreamLoader *) closure;
const uint8_t *data = reinterpret_cast<const uint8_t *>(fromSegment);
uint32_t consumedCount = 0;
nsresult rv;
if (self->mData.empty()) {
// Shortcut when observer wants to keep the listener's buffer empty.
rv = self->mObserver->OnIncrementalData(self, self->mContext,
count, data, &consumedCount);
if (rv != NS_OK) {
return rv;
}
if (consumedCount > count) {
return NS_ERROR_INVALID_ARG;
}
if (consumedCount < count) {
if (!self->mData.append(fromSegment + consumedCount,
count - consumedCount)) {
self->mData.clearAndFree();
return NS_ERROR_OUT_OF_MEMORY;
}
}
} else {
// We have some non-consumed data from previous OnIncrementalData call,
// appending new data and reporting combined data.
if (!self->mData.append(fromSegment, count)) {
self->mData.clearAndFree();
return NS_ERROR_OUT_OF_MEMORY;
}
size_t length = self->mData.length();
uint32_t reportCount = length > UINT32_MAX ? UINT32_MAX : (uint32_t)length;
uint8_t* elems = self->mData.extractOrCopyRawBuffer();
rv = self->mObserver->OnIncrementalData(self, self->mContext,
reportCount, elems, &consumedCount);
// We still own elems, freeing its memory when exiting scope.
if (rv != NS_OK) {
free(elems);
return rv;
}
if (consumedCount > reportCount) {
free(elems);
return NS_ERROR_INVALID_ARG;
}
if (consumedCount == length) {
free(elems); // good case -- fully consumed data
} else {
// Adopting elems back (at least its portion).
self->mData.replaceRawBuffer(elems, length);
if (consumedCount > 0) {
self->mData.erase(self->mData.begin() + consumedCount);
}
}
}
self->mBytesConsumed += consumedCount;
*writeCount = count;
return NS_OK;
}
NS_IMETHODIMP
nsIncrementalStreamLoader::OnDataAvailable(nsIRequest* request, nsISupports *ctxt,
nsIInputStream *inStr,
uint64_t sourceOffset, uint32_t count)
{
if (mObserver) {
// provide nsIIncrementalStreamLoader::request during call to OnStreamComplete
mRequest = request;
}
uint32_t countRead;
nsresult rv = inStr->ReadSegments(WriteSegmentFun, this, count, &countRead);
mRequest = nullptr;
return rv;
}
void
nsIncrementalStreamLoader::ReleaseData()
{
mData.clearAndFree();
}
NS_IMETHODIMP
nsIncrementalStreamLoader::CheckListenerChain()
{
return NS_OK;
}