libs/surfaceflinger/Layer.cpp - SHIFTPHONES/android_frameworks_native - Gitiles

 /*
  * Copyright (C) 2007 The Android Open Source Project
  *
  * 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 <stdlib.h>
 #include <stdint.h>
 #include <sys/types.h>

 #include <cutils/properties.h>
 #include <cutils/native_handle.h>

 #include <utils/Errors.h>
 #include <utils/Log.h>
 #include <utils/StopWatch.h>

 #include <ui/PixelFormat.h>
 #include <ui/Surface.h>

 #include "Buffer.h"
 #include "clz.h"
 #include "Layer.h"
 #include "SurfaceFlinger.h"
 #include "DisplayHardware/DisplayHardware.h"


 #define DEBUG_RESIZE    0


 namespace android {

 // ---------------------------------------------------------------------------

 const uint32_t Layer::typeInfo = LayerBaseClient::typeInfo | 4;
 const char* const Layer::typeID = "Layer";

 // ---------------------------------------------------------------------------

 Layer::Layer(SurfaceFlinger* flinger, DisplayID display,
         const sp<Client>& c, int32_t i)
     :   LayerBaseClient(flinger, display, c, i),
         mSecure(false),
         mNeedsBlending(true)
 {
     // no OpenGL operation is possible here, since we might not be
     // in the OpenGL thread.
     mFrontBufferIndex = lcblk->getFrontBuffer();
 }

 Layer::~Layer()
 {
     destroy();
     // the actual buffers will be destroyed here
 }

 // called with SurfaceFlinger::mStateLock as soon as the layer is entered
 // in the purgatory list
 void Layer::onRemoved()
 {
     // wake up the condition
     lcblk->setStatus(NO_INIT);
 }

 void Layer::destroy()
 {
     for (size_t i=0 ; i<NUM_BUFFERS ; i++) {
         if (mTextures[i].name != -1U) {
             glDeleteTextures(1, &mTextures[i].name);
             mTextures[i].name = -1U;
         }
         if (mTextures[i].image != EGL_NO_IMAGE_KHR) {
             EGLDisplay dpy(mFlinger->graphicPlane(0).getEGLDisplay());
             eglDestroyImageKHR(dpy, mTextures[i].image);
             mTextures[i].image = EGL_NO_IMAGE_KHR;
         }
         Mutex::Autolock _l(mLock);
         mBuffers[i].clear();
         mWidth = mHeight = 0;
     }
     mSurface.clear();
 }

 sp<LayerBaseClient::Surface> Layer::createSurface() const
 {
     return mSurface;
 }

 status_t Layer::ditch()
 {
     // the layer is not on screen anymore. free as much resources as possible
     destroy();
     return NO_ERROR;
 }

 status_t Layer::setBuffers( uint32_t w, uint32_t h,
                             PixelFormat format, uint32_t flags)
 {
     PixelFormatInfo info;
     status_t err = getPixelFormatInfo(format, &info);
     if (err) return err;

     uint32_t bufferFlags = 0;
     if (flags & ISurfaceComposer::eSecure)
         bufferFlags |= Buffer::SECURE;

     mFormat = format;
     mWidth = w;
     mHeight = h;
     mSecure = (bufferFlags & Buffer::SECURE) ? true : false;
     mNeedsBlending = (info.h_alpha - info.l_alpha) > 0;
     mBufferFlags = bufferFlags;
     for (size_t i=0 ; i<NUM_BUFFERS ; i++) {
         mBuffers[i] = new Buffer();
     }
     mSurface = new SurfaceLayer(mFlinger, clientIndex(), this);
     return NO_ERROR;
 }

 void Layer::reloadTexture(const Region& dirty)
 {
     Mutex::Autolock _l(mLock);
     sp<Buffer> buffer(getFrontBuffer());
     if (LIKELY(mFlags & DisplayHardware::DIRECT_TEXTURE)) {
         int index = mFrontBufferIndex;
         if (LIKELY(!mTextures[index].dirty)) {
             glBindTexture(GL_TEXTURE_2D, mTextures[index].name);
         } else {
             // we need to recreate the texture
             EGLDisplay dpy(mFlinger->graphicPlane(0).getEGLDisplay());

             // create the new texture name if needed
             if (UNLIKELY(mTextures[index].name == -1U)) {
                 mTextures[index].name = createTexture();
             } else {
                 glBindTexture(GL_TEXTURE_2D, mTextures[index].name);
             }

             // free the previous image
             if (mTextures[index].image != EGL_NO_IMAGE_KHR) {
                 eglDestroyImageKHR(dpy, mTextures[index].image);
                 mTextures[index].image = EGL_NO_IMAGE_KHR;
             }

             // construct an EGL_NATIVE_BUFFER_ANDROID
             android_native_buffer_t* clientBuf = buffer->getNativeBuffer();

             // create the new EGLImageKHR
             const EGLint attrs[] = {
                     EGL_IMAGE_PRESERVED_KHR,    EGL_TRUE,
                     EGL_NONE,                   EGL_NONE
             };
             mTextures[index].image = eglCreateImageKHR(
                     dpy, EGL_NO_CONTEXT, EGL_NATIVE_BUFFER_ANDROID,
                     (EGLClientBuffer)clientBuf, attrs);

             LOGE_IF(mTextures[index].image == EGL_NO_IMAGE_KHR,
                     "eglCreateImageKHR() failed. err=0x%4x",
                     eglGetError());

             if (mTextures[index].image != EGL_NO_IMAGE_KHR) {
                 glEGLImageTargetTexture2DOES(GL_TEXTURE_2D,
                         (GLeglImageOES)mTextures[index].image);
                 GLint error = glGetError();
                 if (UNLIKELY(error != GL_NO_ERROR)) {
                     // this failed, for instance, because we don't support
                     // NPOT.
                     // FIXME: do something!
                     LOGD("layer=%p, glEGLImageTargetTexture2DOES(%p) "
                          "failed err=0x%04x",
                          this, mTextures[index].image, error);
                     mFlags &= ~DisplayHardware::DIRECT_TEXTURE;
                 } else {
                     // Everything went okay!
                     mTextures[index].dirty  = false;
                     mTextures[index].width  = clientBuf->width;
                     mTextures[index].height = clientBuf->height;
                 }
             }
         }
     } else {
         GGLSurface t;
         status_t res = buffer->lock(&t, GRALLOC_USAGE_SW_READ_RARELY);
         LOGE_IF(res, "error %d (%s) locking buffer %p",
                 res, strerror(res), buffer.get());
         if (res == NO_ERROR) {
             if (UNLIKELY(mTextures[0].name == -1U)) {
                 mTextures[0].name = createTexture();
             }
             loadTexture(&mTextures[0], mTextures[0].name, dirty, t);
             buffer->unlock();
         }
     }
 }


 void Layer::onDraw(const Region& clip) const
 {
     const int index = (mFlags & DisplayHardware::DIRECT_TEXTURE) ?
             mFrontBufferIndex : 0;
     GLuint textureName = mTextures[index].name;
     if (UNLIKELY(textureName == -1LU)) {
         //LOGW("Layer %p doesn't have a texture", this);
         // the texture has not been created yet, this Layer has
         // in fact never been drawn into. this happens frequently with
         // SurfaceView.
         clearWithOpenGL(clip);
         return;
     }

     drawWithOpenGL(clip, mTextures[index]);
 }

 sp<SurfaceBuffer> Layer::requestBuffer(int index, int usage)
 {
     sp<Buffer> buffer;

     // this ensures our client doesn't go away while we're accessing
     // the shared area.
     sp<Client> ourClient(client.promote());
     if (ourClient == 0) {
         // oops, the client is already gone
         return buffer;
     }

     /*
      * This is called from the client's Surface::dequeue(). This can happen
      * at any time, especially while we're in the middle of using the
      * buffer 'index' as our front buffer.
      *
      * Make sure the buffer we're resizing is not the front buffer and has been
      * dequeued. Once this condition is asserted, we are guaranteed that this
      * buffer cannot become the front buffer under our feet, since we're called
      * from Surface::dequeue()
      */
     status_t err = lcblk->assertReallocate(index);
     LOGE_IF(err, "assertReallocate(%d) failed (%s)", index, strerror(-err));
     if (err != NO_ERROR) {
         // the surface may have died
         return buffer;
     }

     uint32_t w, h;
     { // scope for the lock
         Mutex::Autolock _l(mLock);
         w = mWidth;
         h = mHeight;
         buffer = mBuffers[index];

         // destroy() could have been called before we get here, we log it
         // because it's uncommon, and the code below should handle it
         LOGW_IF(buffer==0,
                 "mBuffers[%d] is null (mWidth=%d, mHeight=%d)",
                 index, w, h);

         mBuffers[index].clear();
     }

     if (buffer!=0 && buffer->getStrongCount() == 1) {
         err = buffer->reallocate(w, h, mFormat, usage, mBufferFlags);
     } else {
         // here we have to reallocate a new buffer because we could have a
         // client in our process with a reference to it (eg: status bar),
         // and we can't release the handle under its feet.
         buffer.clear();
         buffer = new Buffer(w, h, mFormat, usage, mBufferFlags);
         err = buffer->initCheck();
     }

     if (err || buffer->handle == 0) {
         LOGE_IF(err || buffer->handle == 0,
                 "Layer::requestBuffer(this=%p), index=%d, w=%d, h=%d failed (%s)",
                 this, index, w, h, strerror(-err));
     } else {
         LOGD_IF(DEBUG_RESIZE,
                 "Layer::requestBuffer(this=%p), index=%d, w=%d, h=%d",
                 this, index, w, h);
     }

     if (err == NO_ERROR && buffer->handle != 0) {
         Mutex::Autolock _l(mLock);
         if (mWidth && mHeight) {
             // and we have new buffer
             mBuffers[index] = buffer;
             // texture is now dirty...
             mTextures[index].dirty = true;
         } else {
             // oops we got killed while we were allocating the buffer
             buffer.clear();
         }
     }
     return buffer;
 }

 uint32_t Layer::doTransaction(uint32_t flags)
 {
     const Layer::State& front(drawingState());
     const Layer::State& temp(currentState());

     // Index of the back buffer
     const bool backbufferChanged = (front.w != temp.w) || (front.h != temp.h);
     if (backbufferChanged) {
         // the size changed, we need to ask our client to request a new buffer
         LOGD_IF(DEBUG_RESIZE,
                     "resize (layer=%p), requested (%dx%d), "
                     "drawing (%d,%d), (%dx%d), (%dx%d)",
                     this, int(temp.w), int(temp.h),
                     int(drawingState().w), int(drawingState().h),
                     int(mBuffers[0]->getWidth()), int(mBuffers[0]->getHeight()),
                     int(mBuffers[1]->getWidth()), int(mBuffers[1]->getHeight()));

         // record the new size, form this point on, when the client request a
         // buffer, it'll get the new size.
         setDrawingSize(temp.w, temp.h);

         // we're being resized and there is a freeze display request,
         // acquire a freeze lock, so that the screen stays put
         // until we've redrawn at the new size; this is to avoid
         // glitches upon orientation changes.
         if (mFlinger->hasFreezeRequest()) {
             // if the surface is hidden, don't try to acquire the
             // freeze lock, since hidden surfaces may never redraw
             if (!(front.flags & ISurfaceComposer::eLayerHidden)) {
                 mFreezeLock = mFlinger->getFreezeLock();
             }
         }

         // recompute the visible region
         flags |= Layer::eVisibleRegion;
         this->contentDirty = true;
         // all buffers need reallocation
         lcblk->reallocate();
     }

     if (temp.sequence != front.sequence) {
         if (temp.flags & ISurfaceComposer::eLayerHidden || temp.alpha == 0) {
             // this surface is now hidden, so it shouldn't hold a freeze lock
             // (it may never redraw, which is fine if it is hidden)
             mFreezeLock.clear();
         }
     }

     return LayerBase::doTransaction(flags);
 }

 void Layer::setDrawingSize(uint32_t w, uint32_t h) {
     Mutex::Autolock _l(mLock);
     mWidth = w;
     mHeight = h;
 }

 // ----------------------------------------------------------------------------
 // pageflip handling...
 // ----------------------------------------------------------------------------

 void Layer::lockPageFlip(bool& recomputeVisibleRegions)
 {
     ssize_t buf = lcblk->retireAndLock();
     if (buf < NO_ERROR) {
         //LOGW("nothing to retire (%s)", strerror(-buf));
         // NOTE: here the buffer is locked because we will used
         // for composition later in the loop
         return;
     }

     // we retired a buffer, which becomes the new front buffer
     mFrontBufferIndex = buf;

     // get the dirty region
     sp<Buffer> newFrontBuffer(getBuffer(buf));
     const Region dirty(lcblk->getDirtyRegion(buf));
     mPostedDirtyRegion = dirty.intersect( newFrontBuffer->getBounds() );


     const Layer::State& front(drawingState());
     if (newFrontBuffer->getWidth() == front.w &&
         newFrontBuffer->getHeight() ==front.h) {
         mFreezeLock.clear();
     }

     // FIXME: signal an event if we have more buffers waiting
     // mFlinger->signalEvent();

     reloadTexture( mPostedDirtyRegion );
 }

 void Layer::unlockPageFlip(
         const Transform& planeTransform, Region& outDirtyRegion)
 {
     Region dirtyRegion(mPostedDirtyRegion);
     if (!dirtyRegion.isEmpty()) {
         mPostedDirtyRegion.clear();
         // The dirty region is given in the layer's coordinate space
         // transform the dirty region by the surface's transformation
         // and the global transformation.
         const Layer::State& s(drawingState());
         const Transform tr(planeTransform * s.transform);
         dirtyRegion = tr.transform(dirtyRegion);

         // At this point, the dirty region is in screen space.
         // Make sure it's constrained by the visible region (which
         // is in screen space as well).
         dirtyRegion.andSelf(visibleRegionScreen);
         outDirtyRegion.orSelf(dirtyRegion);
     }
 }

 void Layer::finishPageFlip()
 {
     status_t err = lcblk->unlock( mFrontBufferIndex );
     LOGE_IF(err!=NO_ERROR,
             "layer %p, buffer=%d wasn't locked!",
             this, mFrontBufferIndex);
 }

 // ---------------------------------------------------------------------------

 Layer::SurfaceLayer::SurfaceLayer(const sp<SurfaceFlinger>& flinger,
         SurfaceID id, const sp<Layer>& owner)
     : Surface(flinger, id, owner->getIdentity(), owner)
 {
 }

 Layer::SurfaceLayer::~SurfaceLayer()
 {
 }

 sp<SurfaceBuffer> Layer::SurfaceLayer::requestBuffer(int index, int usage)
 {
     sp<SurfaceBuffer> buffer;
     sp<Layer> owner(getOwner());
     if (owner != 0) {
         LOGE_IF(uint32_t(index)>=NUM_BUFFERS,
                 "getBuffer() index (%d) out of range", index);
         if (uint32_t(index) < NUM_BUFFERS) {
             buffer = owner->requestBuffer(index, usage);
         }
     }
     return buffer;
 }

 // ---------------------------------------------------------------------------


 }; // namespace android
	/*
	* Copyright (C) 2007 The Android Open Source Project
	*
	* 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 <stdlib.h>
	#include <stdint.h>
	#include <sys/types.h>

	#include <cutils/properties.h>
	#include <cutils/native_handle.h>

	#include <utils/Errors.h>
	#include <utils/Log.h>
	#include <utils/StopWatch.h>

	#include <ui/PixelFormat.h>
	#include <ui/Surface.h>

	#include "Buffer.h"
	#include "clz.h"
	#include "Layer.h"
	#include "SurfaceFlinger.h"
	#include "DisplayHardware/DisplayHardware.h"


	#define DEBUG_RESIZE 0


	namespace android {

	// ---------------------------------------------------------------------------

	const uint32_t Layer::typeInfo = LayerBaseClient::typeInfo \| 4;
	const char* const Layer::typeID = "Layer";

	// ---------------------------------------------------------------------------

	Layer::Layer(SurfaceFlinger* flinger, DisplayID display,
	const sp<Client>& c, int32_t i)
	: LayerBaseClient(flinger, display, c, i),
	mSecure(false),
	mNeedsBlending(true)
	{
	// no OpenGL operation is possible here, since we might not be
	// in the OpenGL thread.
	mFrontBufferIndex = lcblk->getFrontBuffer();
	}

	Layer::~Layer()
	{
	destroy();
	// the actual buffers will be destroyed here
	}

	// called with SurfaceFlinger::mStateLock as soon as the layer is entered
	// in the purgatory list
	void Layer::onRemoved()
	{
	// wake up the condition
	lcblk->setStatus(NO_INIT);
	}

	void Layer::destroy()
	{
	for (size_t i=0 ; i<NUM_BUFFERS ; i++) {
	if (mTextures[i].name != -1U) {
	glDeleteTextures(1, &mTextures[i].name);
	mTextures[i].name = -1U;
	}
	if (mTextures[i].image != EGL_NO_IMAGE_KHR) {
	EGLDisplay dpy(mFlinger->graphicPlane(0).getEGLDisplay());
	eglDestroyImageKHR(dpy, mTextures[i].image);
	mTextures[i].image = EGL_NO_IMAGE_KHR;
	}
	Mutex::Autolock _l(mLock);
	mBuffers[i].clear();
	mWidth = mHeight = 0;
	}
	mSurface.clear();
	}

	sp<LayerBaseClient::Surface> Layer::createSurface() const
	{
	return mSurface;
	}

	status_t Layer::ditch()
	{
	// the layer is not on screen anymore. free as much resources as possible
	destroy();
	return NO_ERROR;
	}

	status_t Layer::setBuffers( uint32_t w, uint32_t h,
	PixelFormat format, uint32_t flags)
	{
	PixelFormatInfo info;
	status_t err = getPixelFormatInfo(format, &info);
	if (err) return err;

	uint32_t bufferFlags = 0;
	if (flags & ISurfaceComposer::eSecure)
	bufferFlags \|= Buffer::SECURE;

	mFormat = format;
	mWidth = w;
	mHeight = h;
	mSecure = (bufferFlags & Buffer::SECURE) ? true : false;
	mNeedsBlending = (info.h_alpha - info.l_alpha) > 0;
	mBufferFlags = bufferFlags;
	for (size_t i=0 ; i<NUM_BUFFERS ; i++) {
	mBuffers[i] = new Buffer();
	}
	mSurface = new SurfaceLayer(mFlinger, clientIndex(), this);
	return NO_ERROR;
	}

	void Layer::reloadTexture(const Region& dirty)
	{
	Mutex::Autolock _l(mLock);
	sp<Buffer> buffer(getFrontBuffer());
	if (LIKELY(mFlags & DisplayHardware::DIRECT_TEXTURE)) {
	int index = mFrontBufferIndex;
	if (LIKELY(!mTextures[index].dirty)) {
	glBindTexture(GL_TEXTURE_2D, mTextures[index].name);
	} else {
	// we need to recreate the texture
	EGLDisplay dpy(mFlinger->graphicPlane(0).getEGLDisplay());

	// create the new texture name if needed
	if (UNLIKELY(mTextures[index].name == -1U)) {
	mTextures[index].name = createTexture();
	} else {
	glBindTexture(GL_TEXTURE_2D, mTextures[index].name);
	}

	// free the previous image
	if (mTextures[index].image != EGL_NO_IMAGE_KHR) {
	eglDestroyImageKHR(dpy, mTextures[index].image);
	mTextures[index].image = EGL_NO_IMAGE_KHR;
	}

	// construct an EGL_NATIVE_BUFFER_ANDROID
	android_native_buffer_t* clientBuf = buffer->getNativeBuffer();

	// create the new EGLImageKHR
	const EGLint attrs[] = {
	EGL_IMAGE_PRESERVED_KHR, EGL_TRUE,
	EGL_NONE, EGL_NONE
	};
	mTextures[index].image = eglCreateImageKHR(
	dpy, EGL_NO_CONTEXT, EGL_NATIVE_BUFFER_ANDROID,
	(EGLClientBuffer)clientBuf, attrs);

	LOGE_IF(mTextures[index].image == EGL_NO_IMAGE_KHR,
	"eglCreateImageKHR() failed. err=0x%4x",
	eglGetError());

	if (mTextures[index].image != EGL_NO_IMAGE_KHR) {
	glEGLImageTargetTexture2DOES(GL_TEXTURE_2D,
	(GLeglImageOES)mTextures[index].image);
	GLint error = glGetError();
	if (UNLIKELY(error != GL_NO_ERROR)) {
	// this failed, for instance, because we don't support
	// NPOT.
	// FIXME: do something!
	LOGD("layer=%p, glEGLImageTargetTexture2DOES(%p) "
	"failed err=0x%04x",
	this, mTextures[index].image, error);
	mFlags &= ~DisplayHardware::DIRECT_TEXTURE;
	} else {
	// Everything went okay!
	mTextures[index].dirty = false;
	mTextures[index].width = clientBuf->width;
	mTextures[index].height = clientBuf->height;
	}
	}
	}
	} else {
	GGLSurface t;
	status_t res = buffer->lock(&t, GRALLOC_USAGE_SW_READ_RARELY);
	LOGE_IF(res, "error %d (%s) locking buffer %p",
	res, strerror(res), buffer.get());
	if (res == NO_ERROR) {
	if (UNLIKELY(mTextures[0].name == -1U)) {
	mTextures[0].name = createTexture();
	}
	loadTexture(&mTextures[0], mTextures[0].name, dirty, t);
	buffer->unlock();
	}
	}
	}


	void Layer::onDraw(const Region& clip) const
	{
	const int index = (mFlags & DisplayHardware::DIRECT_TEXTURE) ?
	mFrontBufferIndex : 0;
	GLuint textureName = mTextures[index].name;
	if (UNLIKELY(textureName == -1LU)) {
	//LOGW("Layer %p doesn't have a texture", this);
	// the texture has not been created yet, this Layer has
	// in fact never been drawn into. this happens frequently with
	// SurfaceView.
	clearWithOpenGL(clip);
	return;
	}

	drawWithOpenGL(clip, mTextures[index]);
	}

	sp<SurfaceBuffer> Layer::requestBuffer(int index, int usage)
	{
	sp<Buffer> buffer;

	// this ensures our client doesn't go away while we're accessing
	// the shared area.
	sp<Client> ourClient(client.promote());
	if (ourClient == 0) {
	// oops, the client is already gone
	return buffer;
	}

	/*
	* This is called from the client's Surface::dequeue(). This can happen
	* at any time, especially while we're in the middle of using the
	* buffer 'index' as our front buffer.
	*
	* Make sure the buffer we're resizing is not the front buffer and has been
	* dequeued. Once this condition is asserted, we are guaranteed that this
	* buffer cannot become the front buffer under our feet, since we're called
	* from Surface::dequeue()
	*/
	status_t err = lcblk->assertReallocate(index);
	LOGE_IF(err, "assertReallocate(%d) failed (%s)", index, strerror(-err));
	if (err != NO_ERROR) {
	// the surface may have died
	return buffer;
	}

	uint32_t w, h;
	{ // scope for the lock
	Mutex::Autolock _l(mLock);
	w = mWidth;
	h = mHeight;
	buffer = mBuffers[index];

	// destroy() could have been called before we get here, we log it
	// because it's uncommon, and the code below should handle it
	LOGW_IF(buffer==0,
	"mBuffers[%d] is null (mWidth=%d, mHeight=%d)",
	index, w, h);

	mBuffers[index].clear();
	}

	if (buffer!=0 && buffer->getStrongCount() == 1) {
	err = buffer->reallocate(w, h, mFormat, usage, mBufferFlags);
	} else {
	// here we have to reallocate a new buffer because we could have a
	// client in our process with a reference to it (eg: status bar),
	// and we can't release the handle under its feet.
	buffer.clear();
	buffer = new Buffer(w, h, mFormat, usage, mBufferFlags);
	err = buffer->initCheck();
	}

	if (err \|\| buffer->handle == 0) {
	LOGE_IF(err \|\| buffer->handle == 0,
	"Layer::requestBuffer(this=%p), index=%d, w=%d, h=%d failed (%s)",
	this, index, w, h, strerror(-err));
	} else {
	LOGD_IF(DEBUG_RESIZE,
	"Layer::requestBuffer(this=%p), index=%d, w=%d, h=%d",
	this, index, w, h);
	}

	if (err == NO_ERROR && buffer->handle != 0) {
	Mutex::Autolock _l(mLock);
	if (mWidth && mHeight) {
	// and we have new buffer
	mBuffers[index] = buffer;
	// texture is now dirty...
	mTextures[index].dirty = true;
	} else {
	// oops we got killed while we were allocating the buffer
	buffer.clear();
	}
	}
	return buffer;
	}

	uint32_t Layer::doTransaction(uint32_t flags)
	{
	const Layer::State& front(drawingState());
	const Layer::State& temp(currentState());

	// Index of the back buffer
	const bool backbufferChanged = (front.w != temp.w) \|\| (front.h != temp.h);
	if (backbufferChanged) {
	// the size changed, we need to ask our client to request a new buffer
	LOGD_IF(DEBUG_RESIZE,
	"resize (layer=%p), requested (%dx%d), "
	"drawing (%d,%d), (%dx%d), (%dx%d)",
	this, int(temp.w), int(temp.h),
	int(drawingState().w), int(drawingState().h),
	int(mBuffers[0]->getWidth()), int(mBuffers[0]->getHeight()),
	int(mBuffers[1]->getWidth()), int(mBuffers[1]->getHeight()));

	// record the new size, form this point on, when the client request a
	// buffer, it'll get the new size.
	setDrawingSize(temp.w, temp.h);

	// we're being resized and there is a freeze display request,
	// acquire a freeze lock, so that the screen stays put
	// until we've redrawn at the new size; this is to avoid
	// glitches upon orientation changes.
	if (mFlinger->hasFreezeRequest()) {
	// if the surface is hidden, don't try to acquire the
	// freeze lock, since hidden surfaces may never redraw
	if (!(front.flags & ISurfaceComposer::eLayerHidden)) {
	mFreezeLock = mFlinger->getFreezeLock();
	}
	}

	// recompute the visible region
	flags \|= Layer::eVisibleRegion;
	this->contentDirty = true;
	// all buffers need reallocation
	lcblk->reallocate();
	}

	if (temp.sequence != front.sequence) {
	if (temp.flags & ISurfaceComposer::eLayerHidden \|\| temp.alpha == 0) {
	// this surface is now hidden, so it shouldn't hold a freeze lock
	// (it may never redraw, which is fine if it is hidden)
	mFreezeLock.clear();
	}
	}

	return LayerBase::doTransaction(flags);
	}

	void Layer::setDrawingSize(uint32_t w, uint32_t h) {
	Mutex::Autolock _l(mLock);
	mWidth = w;
	mHeight = h;
	}

	// ----------------------------------------------------------------------------
	// pageflip handling...
	// ----------------------------------------------------------------------------

	void Layer::lockPageFlip(bool& recomputeVisibleRegions)
	{
	ssize_t buf = lcblk->retireAndLock();
	if (buf < NO_ERROR) {
	//LOGW("nothing to retire (%s)", strerror(-buf));
	// NOTE: here the buffer is locked because we will used
	// for composition later in the loop
	return;
	}

	// we retired a buffer, which becomes the new front buffer
	mFrontBufferIndex = buf;

	// get the dirty region
	sp<Buffer> newFrontBuffer(getBuffer(buf));
	const Region dirty(lcblk->getDirtyRegion(buf));
	mPostedDirtyRegion = dirty.intersect( newFrontBuffer->getBounds() );


	const Layer::State& front(drawingState());
	if (newFrontBuffer->getWidth() == front.w &&
	newFrontBuffer->getHeight() ==front.h) {
	mFreezeLock.clear();
	}

	// FIXME: signal an event if we have more buffers waiting
	// mFlinger->signalEvent();

	reloadTexture( mPostedDirtyRegion );
	}

	void Layer::unlockPageFlip(
	const Transform& planeTransform, Region& outDirtyRegion)
	{
	Region dirtyRegion(mPostedDirtyRegion);
	if (!dirtyRegion.isEmpty()) {
	mPostedDirtyRegion.clear();
	// The dirty region is given in the layer's coordinate space
	// transform the dirty region by the surface's transformation
	// and the global transformation.
	const Layer::State& s(drawingState());
	const Transform tr(planeTransform * s.transform);
	dirtyRegion = tr.transform(dirtyRegion);

	// At this point, the dirty region is in screen space.
	// Make sure it's constrained by the visible region (which
	// is in screen space as well).
	dirtyRegion.andSelf(visibleRegionScreen);
	outDirtyRegion.orSelf(dirtyRegion);
	}
	}

	void Layer::finishPageFlip()
	{
	status_t err = lcblk->unlock( mFrontBufferIndex );
	LOGE_IF(err!=NO_ERROR,
	"layer %p, buffer=%d wasn't locked!",
	this, mFrontBufferIndex);
	}

	// ---------------------------------------------------------------------------

	Layer::SurfaceLayer::SurfaceLayer(const sp<SurfaceFlinger>& flinger,
	SurfaceID id, const sp<Layer>& owner)
	: Surface(flinger, id, owner->getIdentity(), owner)
	{
	}

	Layer::SurfaceLayer::~SurfaceLayer()
	{
	}

	sp<SurfaceBuffer> Layer::SurfaceLayer::requestBuffer(int index, int usage)
	{
	sp<SurfaceBuffer> buffer;
	sp<Layer> owner(getOwner());
	if (owner != 0) {
	LOGE_IF(uint32_t(index)>=NUM_BUFFERS,
	"getBuffer() index (%d) out of range", index);
	if (uint32_t(index) < NUM_BUFFERS) {
	buffer = owner->requestBuffer(index, usage);
	}
	}
	return buffer;
	}

	// ---------------------------------------------------------------------------


	}; // namespace android