gfx/layers/ImageDataSerializer.cpp@97036ab72558 (annotated)
gfx/layers/ImageDataSerializer.cpp
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- |
| michael@0 | 2 | * This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 3 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 4 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 5 | |
| michael@0 | 6 | #include "ImageDataSerializer.h" |
| michael@0 | 7 | #include "gfx2DGlue.h" // for SurfaceFormatToImageFormat |
| michael@0 | 8 | #include "gfxImageSurface.h" // for gfxImageSurface |
| michael@0 | 9 | #include "gfxPoint.h" // for gfxIntSize |
| michael@0 | 10 | #include "mozilla/Assertions.h" // for MOZ_ASSERT, etc |
| michael@0 | 11 | #include "mozilla/gfx/2D.h" // for DataSourceSurface, Factory |
| michael@0 | 12 | #include "mozilla/gfx/Tools.h" // for GetAlignedStride, etc |
| michael@0 | 13 | #include "mozilla/mozalloc.h" // for operator delete, etc |
| michael@0 | 14 | |
| michael@0 | 15 | namespace mozilla { |
| michael@0 | 16 | namespace layers { |
| michael@0 | 17 | |
| michael@0 | 18 | using namespace gfx; |
| michael@0 | 19 | |
| michael@0 | 20 | // The Data is layed out as follows: |
| michael@0 | 21 | // |
| michael@0 | 22 | // +-------------------+ -++ --+ <-- ImageDataSerializerBase::mData pointer |
| michael@0 | 23 | // | SurfaceBufferInfo | | | |
| michael@0 | 24 | // +-------------------+ --+ | offset |
| michael@0 | 25 | // | ... | | |
| michael@0 | 26 | // +-------------------+ ------+ |
| michael@0 | 27 | // | | |
| michael@0 | 28 | // | data | |
| michael@0 | 29 | // | | |
| michael@0 | 30 | // +-------------------+ |
| michael@0 | 31 | |
| michael@0 | 32 | // Structure written at the beginning of the data blob containing the image |
| michael@0 | 33 | // (as shown in the figure above). It contains the necessary informations to |
| michael@0 | 34 | // read the image in the blob. |
| michael@0 | 35 | namespace { |
| michael@0 | 36 | struct SurfaceBufferInfo |
| michael@0 | 37 | { |
| michael@0 | 38 | uint32_t width; |
| michael@0 | 39 | uint32_t height; |
| michael@0 | 40 | SurfaceFormat format; |
| michael@0 | 41 | |
| michael@0 | 42 | static uint32_t GetOffset() |
| michael@0 | 43 | { |
| michael@0 | 44 | return GetAlignedStride<16>(sizeof(SurfaceBufferInfo)); |
| michael@0 | 45 | } |
| michael@0 | 46 | }; |
| michael@0 | 47 | } // anonymous namespace |
| michael@0 | 48 | |
| michael@0 | 49 | static SurfaceBufferInfo* |
| michael@0 | 50 | GetBufferInfo(uint8_t* aData, size_t aDataSize) |
| michael@0 | 51 | { |
| michael@0 | 52 | return aDataSize >= sizeof(SurfaceBufferInfo) |
| michael@0 | 53 | ? reinterpret_cast<SurfaceBufferInfo*>(aData) |
| michael@0 | 54 | : nullptr; |
| michael@0 | 55 | } |
| michael@0 | 56 | |
| michael@0 | 57 | void |
| michael@0 | 58 | ImageDataSerializer::InitializeBufferInfo(IntSize aSize, |
| michael@0 | 59 | SurfaceFormat aFormat) |
| michael@0 | 60 | { |
| michael@0 | 61 | SurfaceBufferInfo* info = GetBufferInfo(mData, mDataSize); |
| michael@0 | 62 | MOZ_ASSERT(info); // OK to assert here, this method is client-side-only |
| michael@0 | 63 | info->width = aSize.width; |
| michael@0 | 64 | info->height = aSize.height; |
| michael@0 | 65 | info->format = aFormat; |
| michael@0 | 66 | Validate(); |
| michael@0 | 67 | } |
| michael@0 | 68 | |
| michael@0 | 69 | static inline uint32_t |
| michael@0 | 70 | ComputeStride(SurfaceFormat aFormat, uint32_t aWidth) |
| michael@0 | 71 | { |
| michael@0 | 72 | return GetAlignedStride<4>(BytesPerPixel(aFormat) * aWidth); |
| michael@0 | 73 | } |
| michael@0 | 74 | |
| michael@0 | 75 | uint32_t |
| michael@0 | 76 | ImageDataSerializerBase::ComputeMinBufferSize(IntSize aSize, |
| michael@0 | 77 | SurfaceFormat aFormat) |
| michael@0 | 78 | { |
| michael@0 | 79 | uint32_t bufsize = aSize.height * ComputeStride(aFormat, aSize.width); |
| michael@0 | 80 | return SurfaceBufferInfo::GetOffset() |
| michael@0 | 81 | + GetAlignedStride<16>(bufsize); |
| michael@0 | 82 | } |
| michael@0 | 83 | |
| michael@0 | 84 | void |
| michael@0 | 85 | ImageDataSerializerBase::Validate() |
| michael@0 | 86 | { |
| michael@0 | 87 | mIsValid = false; |
| michael@0 | 88 | if (!mData) { |
| michael@0 | 89 | return; |
| michael@0 | 90 | } |
| michael@0 | 91 | SurfaceBufferInfo* info = GetBufferInfo(mData, mDataSize); |
| michael@0 | 92 | if (!info) { |
| michael@0 | 93 | return; |
| michael@0 | 94 | } |
| michael@0 | 95 | size_t requiredSize = |
| michael@0 | 96 | ComputeMinBufferSize(IntSize(info->width, info->height), info->format); |
| michael@0 | 97 | mIsValid = requiredSize <= mDataSize; |
| michael@0 | 98 | } |
| michael@0 | 99 | |
| michael@0 | 100 | uint8_t* |
| michael@0 | 101 | ImageDataSerializerBase::GetData() |
| michael@0 | 102 | { |
| michael@0 | 103 | MOZ_ASSERT(IsValid()); |
| michael@0 | 104 | return mData + SurfaceBufferInfo::GetOffset(); |
| michael@0 | 105 | } |
| michael@0 | 106 | |
| michael@0 | 107 | uint32_t |
| michael@0 | 108 | ImageDataSerializerBase::GetStride() const |
| michael@0 | 109 | { |
| michael@0 | 110 | MOZ_ASSERT(IsValid()); |
| michael@0 | 111 | SurfaceBufferInfo* info = GetBufferInfo(mData, mDataSize); |
| michael@0 | 112 | return ComputeStride(GetFormat(), info->width); |
| michael@0 | 113 | } |
| michael@0 | 114 | |
| michael@0 | 115 | IntSize |
| michael@0 | 116 | ImageDataSerializerBase::GetSize() const |
| michael@0 | 117 | { |
| michael@0 | 118 | MOZ_ASSERT(IsValid()); |
| michael@0 | 119 | SurfaceBufferInfo* info = GetBufferInfo(mData, mDataSize); |
| michael@0 | 120 | return IntSize(info->width, info->height); |
| michael@0 | 121 | } |
| michael@0 | 122 | |
| michael@0 | 123 | SurfaceFormat |
| michael@0 | 124 | ImageDataSerializerBase::GetFormat() const |
| michael@0 | 125 | { |
| michael@0 | 126 | MOZ_ASSERT(IsValid()); |
| michael@0 | 127 | return GetBufferInfo(mData, mDataSize)->format; |
| michael@0 | 128 | } |
| michael@0 | 129 | |
| michael@0 | 130 | TemporaryRef<gfxImageSurface> |
| michael@0 | 131 | ImageDataSerializerBase::GetAsThebesSurface() |
| michael@0 | 132 | { |
| michael@0 | 133 | MOZ_ASSERT(IsValid()); |
| michael@0 | 134 | IntSize size = GetSize(); |
| michael@0 | 135 | return new gfxImageSurface(GetData(), |
| michael@0 | 136 | gfxIntSize(size.width, size.height), |
| michael@0 | 137 | GetStride(), |
| michael@0 | 138 | SurfaceFormatToImageFormat(GetFormat())); |
| michael@0 | 139 | } |
| michael@0 | 140 | |
| michael@0 | 141 | TemporaryRef<DrawTarget> |
| michael@0 | 142 | ImageDataSerializerBase::GetAsDrawTarget(gfx::BackendType aBackend) |
| michael@0 | 143 | { |
| michael@0 | 144 | MOZ_ASSERT(IsValid()); |
| michael@0 | 145 | return gfx::Factory::CreateDrawTargetForData(aBackend, |
| michael@0 | 146 | GetData(), GetSize(), |
| michael@0 | 147 | GetStride(), GetFormat()); |
| michael@0 | 148 | } |
| michael@0 | 149 | |
| michael@0 | 150 | TemporaryRef<gfx::DataSourceSurface> |
| michael@0 | 151 | ImageDataSerializerBase::GetAsSurface() |
| michael@0 | 152 | { |
| michael@0 | 153 | MOZ_ASSERT(IsValid()); |
| michael@0 | 154 | return Factory::CreateWrappingDataSourceSurface(GetData(), |
| michael@0 | 155 | GetStride(), |
| michael@0 | 156 | GetSize(), |
| michael@0 | 157 | GetFormat()); |
| michael@0 | 158 | } |
| michael@0 | 159 | |
| michael@0 | 160 | } // namespace layers |
| michael@0 | 161 | } // namespace mozilla |
