netwerk/base/MemoryDownloader.cpp

   1 /* -*- Mode: C++; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "MemoryDownloader.h"
   7
   8 #include "mozilla/Assertions.h"
   9 #include "nsIInputStream.h"
  10
  11 namespace mozilla {
  12 namespace net {
  13
  14 NS_IMPL_ISUPPORTS(MemoryDownloader, nsIStreamListener, nsIRequestObserver)
  15
  16 MemoryDownloader::MemoryDownloader(IObserver* aObserver)
  17     : mObserver(aObserver), mStatus(NS_ERROR_NOT_INITIALIZED) {}
  18
  19 NS_IMETHODIMP
  20 MemoryDownloader::OnStartRequest(nsIRequest* aRequest) {
  21   MOZ_ASSERT(!mData);
  22   mData.reset(new FallibleTArray<uint8_t>());
  23   mStatus = NS_OK;
  24   return NS_OK;
  25 }
  26
  27 NS_IMETHODIMP
  28 MemoryDownloader::OnStopRequest(nsIRequest* aRequest, nsresult aStatus) {
  29   MOZ_ASSERT_IF(NS_FAILED(mStatus), NS_FAILED(aStatus));
  30   MOZ_ASSERT(!mData == NS_FAILED(mStatus));
  31   Data data;
  32   data.swap(mData);
  33   RefPtr<IObserver> observer;
  34   observer.swap(mObserver);
  35   observer->OnDownloadComplete(this, aRequest, aStatus, std::move(data));
  36   return NS_OK;
  37 }
  38
  39 nsresult MemoryDownloader::ConsumeData(nsIInputStream* aIn, void* aClosure,
  40                                        const char* aFromRawSegment,
  41                                        uint32_t aToOffset, uint32_t aCount,
  42                                        uint32_t* aWriteCount) {
  43   MemoryDownloader* self = static_cast<MemoryDownloader*>(aClosure);
  44   if (!self->mData->AppendElements(aFromRawSegment, aCount, fallible)) {
  45     // The error returned by ConsumeData isn't propagated to the
  46     // return of ReadSegments, so it has to be passed as state.
  47     self->mStatus = NS_ERROR_OUT_OF_MEMORY;
  48     return NS_ERROR_OUT_OF_MEMORY;
  49   }
  50   *aWriteCount = aCount;
  51   return NS_OK;
  52 }
  53
  54 NS_IMETHODIMP
  55 MemoryDownloader::OnDataAvailable(nsIRequest* aRequest, nsIInputStream* aInStr,
  56                                   uint64_t aSourceOffset, uint32_t aCount) {
  57   uint32_t n;
  58   MOZ_ASSERT(mData);
  59   nsresult rv = aInStr->ReadSegments(ConsumeData, this, aCount, &n);
  60   if (NS_SUCCEEDED(mStatus) && NS_FAILED(rv)) {
  61     mStatus = rv;
  62   }
  63   if (NS_WARN_IF(NS_FAILED(mStatus))) {
  64     mData.reset(nullptr);
  65     return mStatus;
  66   }
  67   return NS_OK;
  68 }
  69
  70 }  // namespace net
  71 }  // namespace mozilla