The Tor Browser: widget/gonk/HwcComposer2D.cpp@ac0c01689b40 (annotated)

widget/gonk/HwcComposer2D.cpp@ac0c01689b40 (annotated)

widget/gonk/HwcComposer2D.cpp

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rw-r--r--

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /*
  * Copyright (c) 2012, 2013 The Linux Foundation. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 #include <android/log.h>
 #include <string.h>
 #include "libdisplay/GonkDisplay.h"
 #include "Framebuffer.h"
 #include "GLContext.h"                  // for GLContext
 #include "HwcUtils.h"
 #include "HwcComposer2D.h"
 #include "mozilla/layers/LayerManagerComposite.h"
 #include "mozilla/layers/PLayerTransaction.h"
 #include "mozilla/layers/ShadowLayerUtilsGralloc.h"
 #include "mozilla/layers/TextureHostOGL.h"  // for TextureHostOGL
 #include "mozilla/StaticPtr.h"
 #include "cutils/properties.h"
 #include "gfx2DGlue.h"
 #if ANDROID_VERSION >= 17
 #include "libdisplay/FramebufferSurface.h"
 #ifndef HWC_BLIT
 #define HWC_BLIT (HWC_FRAMEBUFFER_TARGET + 1)
 #endif
 #endif
 #ifdef LOG_TAG
 #undef LOG_TAG
 #endif
 #define LOG_TAG "HWComposer"
 /*
  * By default the debug message of hwcomposer (LOG_DEBUG level) are undefined,
  * but can be enabled by uncommenting HWC_DEBUG below.
  */
 //#define HWC_DEBUG
 #ifdef HWC_DEBUG
 #define LOGD(args...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, ## args)
 #else
 #define LOGD(args...) ((void)0)
 #endif
 #define LOGI(args...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, ## args)
 #define LOGE(args...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, ## args)
 #define LAYER_COUNT_INCREMENTS 5
 using namespace android;
 using namespace mozilla::layers;
 namespace mozilla {
 static StaticRefPtr<HwcComposer2D> sInstance;
 HwcComposer2D::HwcComposer2D()
     : mHwc(nullptr)
     , mList(nullptr)
     , mMaxLayerCount(0)
     , mColorFill(false)
     , mRBSwapSupport(false)
 #if ANDROID_VERSION >= 17
     , mPrevRetireFence(Fence::NO_FENCE)
     , mPrevDisplayFence(Fence::NO_FENCE)
 #endif
     , mPrepared(false)
 {
 }
 HwcComposer2D::~HwcComposer2D() {
     free(mList);
 }
 int
 HwcComposer2D::Init(hwc_display_t dpy, hwc_surface_t sur)
 {
     MOZ_ASSERT(!Initialized());
     mHwc = (HwcDevice*)GetGonkDisplay()->GetHWCDevice();
     if (!mHwc) {
         LOGE("Failed to initialize hwc");
         return -1;
     }
     nsIntSize screenSize;
     mozilla::Framebuffer::GetSize(&screenSize);
     mScreenRect  = nsIntRect(nsIntPoint(0, 0), screenSize);
 #if ANDROID_VERSION >= 17
     int supported = 0;
     if (mHwc->query) {
         if (mHwc->query(mHwc, HwcUtils::HWC_COLOR_FILL, &supported) == NO_ERROR) {
             mColorFill = !!supported;
         }
         if (mHwc->query(mHwc, HwcUtils::HWC_FORMAT_RB_SWAP, &supported) == NO_ERROR) {
             mRBSwapSupport = !!supported;
         }
     } else {
         mColorFill = false;
         mRBSwapSupport = false;
     }
 #else
     char propValue[PROPERTY_VALUE_MAX];
     property_get("ro.display.colorfill", propValue, "0");
     mColorFill = (atoi(propValue) == 1) ? true : false;
     mRBSwapSupport = true;
 #endif
     mDpy = dpy;
     mSur = sur;
     return 0;
 }
 HwcComposer2D*
 HwcComposer2D::GetInstance()
 {
     if (!sInstance) {
         LOGI("Creating new instance");
         sInstance = new HwcComposer2D();
     }
     return sInstance;
 }
 bool
 HwcComposer2D::ReallocLayerList()
 {
     int size = sizeof(HwcList) +
         ((mMaxLayerCount + LAYER_COUNT_INCREMENTS) * sizeof(HwcLayer));
     HwcList* listrealloc = (HwcList*)realloc(mList, size);
     if (!listrealloc) {
         return false;
     }
     if (!mList) {
         //first alloc, initialize
         listrealloc->numHwLayers = 0;
         listrealloc->flags = 0;
     }
     mList = listrealloc;
     mMaxLayerCount += LAYER_COUNT_INCREMENTS;
     return true;
 }
 void
 HwcComposer2D::setCrop(HwcLayer* layer, hwc_rect_t srcCrop)
 {
 #if ANDROID_VERSION >= 19
     if (mHwc->common.version >= HWC_DEVICE_API_VERSION_1_3) {
         layer->sourceCropf.left = srcCrop.left;
         layer->sourceCropf.top = srcCrop.top;
         layer->sourceCropf.right = srcCrop.right;
         layer->sourceCropf.bottom = srcCrop.bottom;
     } else {
         layer->sourceCrop = srcCrop;
     }
 #else
     layer->sourceCrop = srcCrop;
 #endif
 }
 void
 HwcComposer2D::setHwcGeometry(bool aGeometryChanged)
 {
 #if ANDROID_VERSION >= 19
     mList->flags = aGeometryChanged ? HWC_GEOMETRY_CHANGED : 0;
 #else
     mList->flags = HWC_GEOMETRY_CHANGED;
 #endif
 }
 bool
 HwcComposer2D::PrepareLayerList(Layer* aLayer,
                                 const nsIntRect& aClip,
                                 const gfxMatrix& aParentTransform,
                                 const gfxMatrix& aGLWorldTransform)
 {
     // NB: we fall off this path whenever there are container layers
     // that require intermediate surfaces.  That means all the
     // GetEffective*() coordinates are relative to the framebuffer.
     bool fillColor = false;
     const nsIntRegion& visibleRegion = aLayer->GetEffectiveVisibleRegion();
     if (visibleRegion.IsEmpty()) {
         return true;
     }
     uint8_t opacity = std::min(0xFF, (int)(aLayer->GetEffectiveOpacity() * 256.0));
 #if ANDROID_VERSION < 18
     if (opacity < 0xFF) {
         LOGD("%s Layer has planar semitransparency which is unsupported", aLayer->Name());
         return false;
     }
 #endif
     nsIntRect clip;
     if (!HwcUtils::CalculateClipRect(aParentTransform * aGLWorldTransform,
                                      aLayer->GetEffectiveClipRect(),
                                      aClip,
                                      &clip))
     {
         LOGD("%s Clip rect is empty. Skip layer", aLayer->Name());
         return true;
     }
     // HWC supports only the following 2D transformations:
     //
     // Scaling via the sourceCrop and displayFrame in HwcLayer
     // Translation via the sourceCrop and displayFrame in HwcLayer
     // Rotation (in square angles only) via the HWC_TRANSFORM_ROT_* flags
     // Reflection (horizontal and vertical) via the HWC_TRANSFORM_FLIP_* flags
     //
     // A 2D transform with PreservesAxisAlignedRectangles() has all the attributes
     // above
     gfxMatrix transform;
     gfx3DMatrix transform3D;
     gfx::To3DMatrix(aLayer->GetEffectiveTransform(), transform3D);
     if (!transform3D.Is2D(&transform) || !transform.PreservesAxisAlignedRectangles()) {
         LOGD("Layer has a 3D transform or a non-square angle rotation");
         return false;
     }
     if (ContainerLayer* container = aLayer->AsContainerLayer()) {
         nsAutoTArray<Layer*, 12> children;
         container->SortChildrenBy3DZOrder(children);
         for (uint32_t i = 0; i < children.Length(); i++) {
             if (!PrepareLayerList(children[i], clip, transform, aGLWorldTransform)) {
                 return false;
             }
         }
         return true;
     }
     LayerRenderState state = aLayer->GetRenderState();
     nsIntSize surfaceSize;
     if (state.mSurface.get()) {
         surfaceSize = state.mSize;
     } else {
         if (aLayer->AsColorLayer() && mColorFill) {
             fillColor = true;
         } else {
             LOGD("%s Layer doesn't have a gralloc buffer", aLayer->Name());
             return false;
         }
     }
     // Buffer rotation is not to be confused with the angled rotation done by a transform matrix
     // It's a fancy ThebesLayer feature used for scrolling
     if (state.BufferRotated()) {
         LOGD("%s Layer has a rotated buffer", aLayer->Name());
         return false;
     }
     nsIntRect visibleRect = visibleRegion.GetBounds();
     nsIntRect bufferRect;
     if (fillColor) {
         bufferRect = nsIntRect(visibleRect);
     } else {
         if(state.mHasOwnOffset) {
             bufferRect = nsIntRect(state.mOffset.x, state.mOffset.y,
                                    state.mSize.width, state.mSize.height);
         } else {
             //Since the buffer doesn't have its own offset, assign the whole
             //surface size as its buffer bounds
             bufferRect = nsIntRect(0, 0, state.mSize.width, state.mSize.height);
         }
     }
     hwc_rect_t sourceCrop, displayFrame;
     if(!HwcUtils::PrepareLayerRects(visibleRect,
                           transform * aGLWorldTransform,
                           clip,
                           bufferRect,
                           state.YFlipped(),
                           &(sourceCrop),
                           &(displayFrame)))
     {
         return true;
     }
     // OK!  We can compose this layer with hwc.
     int current = mList ? mList->numHwLayers : 0;
     // Do not compose any layer below full-screen Opaque layer
     // Note: It can be generalized to non-fullscreen Opaque layers.
     bool isOpaque = (opacity == 0xFF) && (aLayer->GetContentFlags() & Layer::CONTENT_OPAQUE);
     if (current && isOpaque) {
         nsIntRect displayRect = nsIntRect(displayFrame.left, displayFrame.top,
             displayFrame.right - displayFrame.left, displayFrame.bottom - displayFrame.top);
         if (displayRect.Contains(mScreenRect)) {
             // In z-order, all previous layers are below
             // the current layer. We can ignore them now.
             mList->numHwLayers = current = 0;
             mHwcLayerMap.Clear();
         }
     }
     if (!mList || current >= mMaxLayerCount) {
         if (!ReallocLayerList() || current >= mMaxLayerCount) {
             LOGE("PrepareLayerList failed! Could not increase the maximum layer count");
             return false;
         }
     }
     HwcLayer& hwcLayer = mList->hwLayers[current];
     hwcLayer.flags = 0;
     if (ContainerLayer* parent = aLayer->GetParent()) {
         if (parent->UseIntermediateSurface()) {
             LOGD("Parent container needs intermediate surface");
             hwcLayer.flags = HWC_SKIP_LAYER;
 #if ANDROID_VERSION < 18
             // No partial HWC Composition on older versions
             return false;
 #endif
         }
     }
     hwcLayer.displayFrame = displayFrame;
     setCrop(&hwcLayer, sourceCrop);
     buffer_handle_t handle = fillColor ? nullptr : state.mSurface->getNativeBuffer()->handle;
     hwcLayer.handle = handle;
     hwcLayer.hints = 0;
     hwcLayer.blending = isOpaque ? HWC_BLENDING_NONE : HWC_BLENDING_PREMULT;
 #if ANDROID_VERSION >= 17
     hwcLayer.compositionType = HWC_FRAMEBUFFER;
     hwcLayer.acquireFenceFd = -1;
     hwcLayer.releaseFenceFd = -1;
 #if ANDROID_VERSION >= 18
     hwcLayer.planeAlpha = opacity;
 #endif
 #else
     hwcLayer.compositionType = HwcUtils::HWC_USE_COPYBIT;
 #endif
     if (!fillColor) {
         if (state.FormatRBSwapped()) {
             if (!mRBSwapSupport) {
                 LOGD("No R/B swap support in H/W Composer");
                 return false;
             }
             hwcLayer.flags |= HwcUtils::HWC_FORMAT_RB_SWAP;
         }
         // Translation and scaling have been addressed in PrepareLayerRects().
         // Given the above and that we checked for PreservesAxisAlignedRectangles()
         // the only possible transformations left to address are
         // square angle rotation and horizontal/vertical reflection.
         //
         // The rotation and reflection permutations total 16 but can be
         // reduced to 8 transformations after eliminating redundancies.
         //
         // All matrices represented here are in the form
         //
         // | xx  xy |
         // | yx  yy |
         //
         // And ignore scaling.
         //
         // Reflection is applied before rotation
         gfxMatrix rotation = transform * aGLWorldTransform;
         // Compute fuzzy zero like PreservesAxisAlignedRectangles()
         if (fabs(rotation.xx) < 1e-6) {
             if (rotation.xy < 0) {
                 if (rotation.yx > 0) {
                     // 90 degree rotation
                     //
                     // |  0  -1  |
                     // |  1   0  |
                     //
                     hwcLayer.transform = HWC_TRANSFORM_ROT_90;
                     LOGD("Layer rotated 90 degrees");
                 }
                 else {
                     // Horizontal reflection then 90 degree rotation
                     //
                     // |  0  -1  | | -1   0  | = |  0  -1  |
                     // |  1   0  | |  0   1  |   | -1   0  |
                     //
                     // same as vertical reflection then 270 degree rotation
                     //
                     // |  0   1  | |  1   0  | = |  0  -1  |
                     // | -1   0  | |  0  -1  |   | -1   0  |
                     //
                     hwcLayer.transform = HWC_TRANSFORM_ROT_90 | HWC_TRANSFORM_FLIP_H;
                     LOGD("Layer vertically reflected then rotated 270 degrees");
                 }
             } else {
                 if (rotation.yx < 0) {
                     // 270 degree rotation
                     //
                     // |  0   1  |
                     // | -1   0  |
                     //
                     hwcLayer.transform = HWC_TRANSFORM_ROT_270;
                     LOGD("Layer rotated 270 degrees");
                 }
                 else {
                     // Vertical reflection then 90 degree rotation
                     //
                     // |  0   1  | | -1   0  | = |  0   1  |
                     // | -1   0  | |  0   1  |   |  1   0  |
                     //
                     // Same as horizontal reflection then 270 degree rotation
                     //
                     // |  0  -1  | |  1   0  | = |  0   1  |
                     // |  1   0  | |  0  -1  |   |  1   0  |
                     //
                     hwcLayer.transform = HWC_TRANSFORM_ROT_90 | HWC_TRANSFORM_FLIP_V;
                     LOGD("Layer horizontally reflected then rotated 270 degrees");
                 }
             }
         } else if (rotation.xx < 0) {
             if (rotation.yy > 0) {
                 // Horizontal reflection
                 //
                 // | -1   0  |
                 // |  0   1  |
                 //
                 hwcLayer.transform = HWC_TRANSFORM_FLIP_H;
                 LOGD("Layer rotated 180 degrees");
             }
             else {
                 // 180 degree rotation
                 //
                 // | -1   0  |
                 // |  0  -1  |
                 //
                 // Same as horizontal and vertical reflection
                 //
                 // | -1   0  | |  1   0  | = | -1   0  |
                 // |  0   1  | |  0  -1  |   |  0  -1  |
                 //
                 hwcLayer.transform = HWC_TRANSFORM_ROT_180;
                 LOGD("Layer rotated 180 degrees");
             }
         } else {
             if (rotation.yy < 0) {
                 // Vertical reflection
                 //
                 // |  1   0  |
                 // |  0  -1  |
                 //
                 hwcLayer.transform = HWC_TRANSFORM_FLIP_V;
                 LOGD("Layer rotated 180 degrees");
             }
             else {
                 // No rotation or reflection
                 //
                 // |  1   0  |
                 // |  0   1  |
                 //
                 hwcLayer.transform = 0;
             }
         }
         if (state.YFlipped()) {
            // Invert vertical reflection flag if it was already set
            hwcLayer.transform ^= HWC_TRANSFORM_FLIP_V;
         }
         hwc_region_t region;
         if (visibleRegion.GetNumRects() > 1) {
             mVisibleRegions.push_back(HwcUtils::RectVector());
             HwcUtils::RectVector* visibleRects = &(mVisibleRegions.back());
             if(!HwcUtils::PrepareVisibleRegion(visibleRegion,
                                      transform * aGLWorldTransform,
                                      clip,
                                      bufferRect,
                                      visibleRects)) {
                 return true;
             }
             region.numRects = visibleRects->size();
             region.rects = &((*visibleRects)[0]);
         } else {
             region.numRects = 1;
             region.rects = &(hwcLayer.displayFrame);
         }
         hwcLayer.visibleRegionScreen = region;
     } else {
         hwcLayer.flags |= HwcUtils::HWC_COLOR_FILL;
         ColorLayer* colorLayer = aLayer->AsColorLayer();
         if (colorLayer->GetColor().a < 1.0) {
             LOGD("Color layer has semitransparency which is unsupported");
             return false;
         }
         hwcLayer.transform = colorLayer->GetColor().Packed();
     }
     mHwcLayerMap.AppendElement(static_cast<LayerComposite*>(aLayer->ImplData()));
     mList->numHwLayers++;
     return true;
 }
 #if ANDROID_VERSION >= 17
 bool
 HwcComposer2D::TryHwComposition()
 {
     FramebufferSurface* fbsurface = (FramebufferSurface*)(GetGonkDisplay()->GetFBSurface());
     if (!(fbsurface && fbsurface->lastHandle)) {
         LOGD("H/W Composition failed. FBSurface not initialized.");
         return false;
     }
     // Add FB layer
     int idx = mList->numHwLayers++;
     if (idx >= mMaxLayerCount) {
         if (!ReallocLayerList() || idx >= mMaxLayerCount) {
             LOGE("TryHwComposition failed! Could not add FB layer");
             return false;
         }
     }
     Prepare(fbsurface->lastHandle, -1);
     /* Possible composition paths, after hwc prepare:
 . GPU Composition
 . BLIT Composition
 . Full OVERLAY Composition
 . Partial OVERLAY Composition (GPU + OVERLAY) */
     bool gpuComposite = false;
     bool blitComposite = false;
     bool overlayComposite = true;
     for (int j=0; j < idx; j++) {
         if (mList->hwLayers[j].compositionType == HWC_FRAMEBUFFER ||
             mList->hwLayers[j].compositionType == HWC_BLIT) {
             // Full OVERLAY composition is not possible on this frame
             // It is either GPU / BLIT / partial OVERLAY composition.
             overlayComposite = false;
             break;
         }
     }
     if (!overlayComposite) {
         for (int k=0; k < idx; k++) {
             switch (mList->hwLayers[k].compositionType) {
                 case HWC_FRAMEBUFFER:
                     gpuComposite = true;
                     break;
                 case HWC_BLIT:
                     blitComposite = true;
                     break;
                 case HWC_OVERLAY:
                     // HWC will compose HWC_OVERLAY layers in partial
                     // Overlay Composition, set layer composition flag
                     // on mapped LayerComposite to skip GPU composition
                     mHwcLayerMap[k]->SetLayerComposited(true);
                     if ((mList->hwLayers[k].hints & HWC_HINT_CLEAR_FB) &&
                         (mList->hwLayers[k].blending == HWC_BLENDING_NONE)) {
                         // Clear visible rect on FB with transparent pixels.
                         hwc_rect_t r = mList->hwLayers[k].displayFrame;
                         mHwcLayerMap[k]->SetClearRect(nsIntRect(r.left, r.top,
                                                                 r.right - r.left,
                                                                 r.bottom - r.top));
                     }
                     break;
                 default:
                     break;
             }
         }
         if (gpuComposite) {
             // GPU or partial OVERLAY Composition
             return false;
         } else if (blitComposite) {
             // BLIT Composition, flip FB target
             GetGonkDisplay()->UpdateFBSurface(mDpy, mSur);
             FramebufferSurface* fbsurface = (FramebufferSurface*)(GetGonkDisplay()->GetFBSurface());
             if (!fbsurface) {
                 LOGE("H/W Composition failed. NULL FBSurface.");
                 return false;
             }
             mList->hwLayers[idx].handle = fbsurface->lastHandle;
             mList->hwLayers[idx].acquireFenceFd = fbsurface->GetPrevFBAcquireFd();
         }
     }
     // BLIT or full OVERLAY Composition
     Commit();
     GetGonkDisplay()->SetFBReleaseFd(mList->hwLayers[idx].releaseFenceFd);
     return true;
 }
 bool
 HwcComposer2D::Render(EGLDisplay dpy, EGLSurface sur)
 {
     if (!mList) {
         // After boot, HWC list hasn't been created yet
         return GetGonkDisplay()->SwapBuffers(dpy, sur);
     }
     GetGonkDisplay()->UpdateFBSurface(dpy, sur);
     FramebufferSurface* fbsurface = (FramebufferSurface*)(GetGonkDisplay()->GetFBSurface());
     if (!fbsurface) {
         LOGE("H/W Composition failed. FBSurface not initialized.");
         return false;
     }
     if (mPrepared) {
         // No mHwc prepare, if already prepared in current draw cycle
         mList->hwLayers[mList->numHwLayers - 1].handle = fbsurface->lastHandle;
         mList->hwLayers[mList->numHwLayers - 1].acquireFenceFd = fbsurface->GetPrevFBAcquireFd();
     } else {
         mList->flags = HWC_GEOMETRY_CHANGED;
         mList->numHwLayers = 2;
         mList->hwLayers[0].hints = 0;
         mList->hwLayers[0].compositionType = HWC_FRAMEBUFFER;
         mList->hwLayers[0].flags = HWC_SKIP_LAYER;
         mList->hwLayers[0].backgroundColor = {0};
         mList->hwLayers[0].acquireFenceFd = -1;
         mList->hwLayers[0].releaseFenceFd = -1;
         mList->hwLayers[0].displayFrame = {0, 0, mScreenRect.width, mScreenRect.height};
         Prepare(fbsurface->lastHandle, fbsurface->GetPrevFBAcquireFd());
     }
     // GPU or partial HWC Composition
     Commit();
     GetGonkDisplay()->SetFBReleaseFd(mList->hwLayers[mList->numHwLayers - 1].releaseFenceFd);
     return true;
 }
 void
 HwcComposer2D::Prepare(buffer_handle_t fbHandle, int fence)
 {
     int idx = mList->numHwLayers - 1;
     const hwc_rect_t r = {0, 0, mScreenRect.width, mScreenRect.height};
     hwc_display_contents_1_t *displays[HWC_NUM_DISPLAY_TYPES] = { nullptr };
     displays[HWC_DISPLAY_PRIMARY] = mList;
     mList->outbufAcquireFenceFd = -1;
     mList->outbuf = nullptr;
     mList->retireFenceFd = -1;
     mList->hwLayers[idx].hints = 0;
     mList->hwLayers[idx].flags = 0;
     mList->hwLayers[idx].transform = 0;
     mList->hwLayers[idx].handle = fbHandle;
     mList->hwLayers[idx].blending = HWC_BLENDING_PREMULT;
     mList->hwLayers[idx].compositionType = HWC_FRAMEBUFFER_TARGET;
     setCrop(&mList->hwLayers[idx], r);
     mList->hwLayers[idx].displayFrame = r;
     mList->hwLayers[idx].visibleRegionScreen.numRects = 1;
     mList->hwLayers[idx].visibleRegionScreen.rects = &mList->hwLayers[idx].displayFrame;
     mList->hwLayers[idx].acquireFenceFd = fence;
     mList->hwLayers[idx].releaseFenceFd = -1;
 #if ANDROID_VERSION >= 18
     mList->hwLayers[idx].planeAlpha = 0xFF;
 #endif
     if (mPrepared) {
         LOGE("Multiple hwc prepare calls!");
     }
     mHwc->prepare(mHwc, HWC_NUM_DISPLAY_TYPES, displays);
     mPrepared = true;
 }
 bool
 HwcComposer2D::Commit()
 {
     hwc_display_contents_1_t *displays[HWC_NUM_DISPLAY_TYPES] = { nullptr };
     displays[HWC_DISPLAY_PRIMARY] = mList;
     int err = mHwc->set(mHwc, HWC_NUM_DISPLAY_TYPES, displays);
     mPrevDisplayFence = mPrevRetireFence;
     mPrevRetireFence = Fence::NO_FENCE;
     for (uint32_t j=0; j < (mList->numHwLayers - 1); j++) {
         if (mList->hwLayers[j].releaseFenceFd >= 0) {
             int fd = mList->hwLayers[j].releaseFenceFd;
             mList->hwLayers[j].releaseFenceFd = -1;
             sp<Fence> fence = new Fence(fd);
             LayerRenderState state = mHwcLayerMap[j]->GetLayer()->GetRenderState();
             if (!state.mTexture) {
                 continue;
             }
             TextureHostOGL* texture = state.mTexture->AsHostOGL();
             if (!texture) {
                 continue;
             }
             texture->SetReleaseFence(fence);
        }
    }
     if (mList->retireFenceFd >= 0) {
         mPrevRetireFence = new Fence(mList->retireFenceFd);
     }
     mPrepared = false;
     return !err;
 }
 void
 HwcComposer2D::Reset()
 {
     LOGD("hwcomposer is already prepared, reset with null set");
     hwc_display_contents_1_t *displays[HWC_NUM_DISPLAY_TYPES] = { nullptr };
     displays[HWC_DISPLAY_PRIMARY] = nullptr;
     mHwc->set(mHwc, HWC_DISPLAY_PRIMARY, displays);
     mPrepared = false;
 }
 #else
 bool
 HwcComposer2D::TryHwComposition()
 {
     return !mHwc->set(mHwc, mDpy, mSur, mList);
 }
 bool
 HwcComposer2D::Render(EGLDisplay dpy, EGLSurface sur)
 {
     return GetGonkDisplay()->SwapBuffers(dpy, sur);
 }
 void
 HwcComposer2D::Reset()
 {
     mPrepared = false;
 }
 #endif
 bool
 HwcComposer2D::TryRender(Layer* aRoot,
                          const gfx::Matrix& GLWorldTransform,
                          bool aGeometryChanged)
 {
     gfxMatrix aGLWorldTransform = ThebesMatrix(GLWorldTransform);
     if (!aGLWorldTransform.PreservesAxisAlignedRectangles()) {
         LOGD("Render aborted. World transform has non-square angle rotation");
         return false;
     }
     MOZ_ASSERT(Initialized());
     if (mList) {
         setHwcGeometry(aGeometryChanged);
         mList->numHwLayers = 0;
         mHwcLayerMap.Clear();
     }
     if (mPrepared) {
         Reset();
     }
     // XXX: The clear() below means all rect vectors will be have to be
     // reallocated. We may want to avoid this if possible
     mVisibleRegions.clear();
     MOZ_ASSERT(mHwcLayerMap.IsEmpty());
     if (!PrepareLayerList(aRoot,
                           mScreenRect,
                           gfxMatrix(),
                           aGLWorldTransform))
     {
         LOGD("Render aborted. Nothing was drawn to the screen");
         return false;
     }
     if (!TryHwComposition()) {
         LOGD("H/W Composition failed");
         return false;
     }
     LOGD("Frame rendered");
     return true;
 }
 } // namespace mozilla

The Tor Browser / annotate

widget/gonk/HwcComposer2D.cpp@ac0c01689b40 (annotated)

widget/gonk/HwcComposer2D.cpp