ipc/glue/RandomAccessStreamUtils.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "RandomAccessStreamUtils.h"
   8
   9 #include "mozilla/NotNull.h"
  10 #include "mozilla/Result.h"
  11 #include "mozilla/ResultVariant.h"
  12 #include "mozilla/dom/quota/FileStreams.h"
  13 #include "mozilla/ipc/RandomAccessStreamParams.h"
  14 #include "nsFileStreams.h"
  15 #include "nsIInterfaceRequestor.h"
  16 #include "nsIRandomAccessStream.h"
  17
  18 namespace mozilla::ipc {
  19
  20 RandomAccessStreamParams SerializeRandomAccessStream(
  21     MovingNotNull<nsCOMPtr<nsIRandomAccessStream>> aStream,
  22     nsIInterfaceRequestor* aCallbacks) {
  23   NotNull<nsCOMPtr<nsIRandomAccessStream>> stream = std::move(aStream);
  24
  25   RandomAccessStreamParams streamParams = stream->Serialize(aCallbacks);
  26
  27   MOZ_ASSERT(streamParams.type() != RandomAccessStreamParams::T__None);
  28
  29   return streamParams;
  30 }
  31
  32 Maybe<RandomAccessStreamParams> SerializeRandomAccessStream(
  33     nsCOMPtr<nsIRandomAccessStream> aStream,
  34     nsIInterfaceRequestor* aCallbacks) {
  35   if (!aStream) {
  36     return Nothing();
  37   }
  38
  39   return Some(SerializeRandomAccessStream(
  40       WrapMovingNotNullUnchecked(std::move(aStream)), aCallbacks));
  41 }
  42
  43 Result<MovingNotNull<nsCOMPtr<nsIRandomAccessStream>>, bool>
  44 DeserializeRandomAccessStream(RandomAccessStreamParams& aStreamParams) {
  45   nsCOMPtr<nsIRandomAccessStream> stream;
  46
  47   switch (aStreamParams.type()) {
  48     case RandomAccessStreamParams::TFileRandomAccessStreamParams:
  49       nsFileRandomAccessStream::Create(NS_GET_IID(nsIFileRandomAccessStream),
  50                                        getter_AddRefs(stream));
  51       break;
  52
  53     case RandomAccessStreamParams::TLimitingFileRandomAccessStreamParams:
  54       stream = new dom::quota::FileRandomAccessStream();
  55       break;
  56
  57     default:
  58       MOZ_ASSERT_UNREACHABLE("Unknown params!");
  59       return Err(false);
  60   }
  61
  62   MOZ_ASSERT(stream);
  63
  64   if (!stream->Deserialize(aStreamParams)) {
  65     MOZ_ASSERT_UNREACHABLE("Deserialize failed!");
  66     return Err(false);
  67   }
  68
  69   return WrapMovingNotNullUnchecked(std::move(stream));
  70 }
  71
  72 Result<nsCOMPtr<nsIRandomAccessStream>, bool> DeserializeRandomAccessStream(
  73     Maybe<RandomAccessStreamParams>& aStreamParams) {
  74   if (aStreamParams.isNothing()) {
  75     return nsCOMPtr<nsIRandomAccessStream>();
  76   }
  77
  78   auto res = DeserializeRandomAccessStream(aStreamParams.ref());
  79   if (res.isErr()) {
  80     return res.propagateErr();
  81   }
  82
  83   MovingNotNull<nsCOMPtr<nsIRandomAccessStream>> stream = res.unwrap();
  84
  85   return std::move(stream).unwrapBasePtr();
  86 }
  87
  88 }  // namespace mozilla::ipc