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, nsISupports* aCtxt) {
  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, nsISupports* aCtxt,
  29                                 nsresult aStatus) {
  30   MOZ_ASSERT_IF(NS_FAILED(mStatus), NS_FAILED(aStatus));
  31   MOZ_ASSERT(!mData == NS_FAILED(mStatus));
  32   Data data;
  33   data.swap(mData);
  34   RefPtr<IObserver> observer;
  35   observer.swap(mObserver);
  36   observer->OnDownloadComplete(this, aRequest, aCtxt, aStatus, std::move(data));
  37   return NS_OK;
  38 }
  39
  40 nsresult MemoryDownloader::ConsumeData(nsIInputStream* aIn, void* aClosure,
  41                                        const char* aFromRawSegment,
  42                                        uint32_t aToOffset, uint32_t aCount,
  43                                        uint32_t* aWriteCount) {
  44   MemoryDownloader* self = static_cast<MemoryDownloader*>(aClosure);
  45   if (!self->mData->AppendElements(aFromRawSegment, aCount, fallible)) {
  46     // The error returned by ConsumeData isn't propagated to the
  47     // return of ReadSegments, so it has to be passed as state.
  48     self->mStatus = NS_ERROR_OUT_OF_MEMORY;
  49     return NS_ERROR_OUT_OF_MEMORY;
  50   }
  51   *aWriteCount = aCount;
  52   return NS_OK;
  53 }
  54
  55 NS_IMETHODIMP
  56 MemoryDownloader::OnDataAvailable(nsIRequest* aRequest, nsISupports* aCtxt,
  57                                   nsIInputStream* aInStr,
  58                                   uint64_t aSourceOffset, uint32_t aCount) {
  59   uint32_t n;
  60   MOZ_ASSERT(mData);
  61   nsresult rv = aInStr->ReadSegments(ConsumeData, this, aCount, &n);
  62   if (NS_SUCCEEDED(mStatus) && NS_FAILED(rv)) {
  63     mStatus = rv;
  64   }
  65   if (NS_WARN_IF(NS_FAILED(mStatus))) {
  66     mData.reset(nullptr);
  67     return mStatus;
  68   }
  69   return NS_OK;
  70 }
  71
  72 }  // namespace net
  73 }  // namespace mozilla