src/core/SkWriteBuffer.cpp - skia - Git at Google


 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "SkWriteBuffer.h"
 #include "SkBitmap.h"
 #include "SkBitmapHeap.h"
 #include "SkData.h"
 #include "SkPixelRef.h"
 #include "SkPtrRecorder.h"
 #include "SkStream.h"
 #include "SkTypeface.h"

 SkWriteBuffer::SkWriteBuffer(uint32_t flags)
     : fFlags(flags)
     , fFactorySet(NULL)
     , fNamedFactorySet(NULL)
     , fBitmapHeap(NULL)
     , fTFSet(NULL) {
 }

 SkWriteBuffer::SkWriteBuffer(void* storage, size_t storageSize, uint32_t flags)
     : fFlags(flags)
     , fFactorySet(NULL)
     , fNamedFactorySet(NULL)
     , fWriter(storage, storageSize)
     , fBitmapHeap(NULL)
     , fTFSet(NULL) {
 }

 SkWriteBuffer::~SkWriteBuffer() {
     SkSafeUnref(fFactorySet);
     SkSafeUnref(fNamedFactorySet);
     SkSafeUnref(fBitmapHeap);
     SkSafeUnref(fTFSet);
 }

 void SkWriteBuffer::writeByteArray(const void* data, size_t size) {
     fWriter.write32(SkToU32(size));
     fWriter.writePad(data, size);
 }

 void SkWriteBuffer::writeBool(bool value) {
     fWriter.writeBool(value);
 }

 void SkWriteBuffer::writeFixed(SkFixed value) {
     fWriter.write32(value);
 }

 void SkWriteBuffer::writeScalar(SkScalar value) {
     fWriter.writeScalar(value);
 }

 void SkWriteBuffer::writeScalarArray(const SkScalar* value, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(value, count * sizeof(SkScalar));
 }

 void SkWriteBuffer::writeInt(int32_t value) {
     fWriter.write32(value);
 }

 void SkWriteBuffer::writeIntArray(const int32_t* value, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(value, count * sizeof(int32_t));
 }

 void SkWriteBuffer::writeUInt(uint32_t value) {
     fWriter.write32(value);
 }

 void SkWriteBuffer::write32(int32_t value) {
     fWriter.write32(value);
 }

 void SkWriteBuffer::writeString(const char* value) {
     fWriter.writeString(value);
 }

 void SkWriteBuffer::writeEncodedString(const void* value, size_t byteLength,
                                               SkPaint::TextEncoding encoding) {
     fWriter.writeInt(encoding);
     fWriter.writeInt(SkToU32(byteLength));
     fWriter.write(value, byteLength);
 }


 void SkWriteBuffer::writeColor(const SkColor& color) {
     fWriter.write32(color);
 }

 void SkWriteBuffer::writeColorArray(const SkColor* color, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(color, count * sizeof(SkColor));
 }

 void SkWriteBuffer::writePoint(const SkPoint& point) {
     fWriter.writeScalar(point.fX);
     fWriter.writeScalar(point.fY);
 }

 void SkWriteBuffer::writePointArray(const SkPoint* point, uint32_t count) {
     fWriter.write32(count);
     fWriter.write(point, count * sizeof(SkPoint));
 }

 void SkWriteBuffer::writeMatrix(const SkMatrix& matrix) {
     fWriter.writeMatrix(matrix);
 }

 void SkWriteBuffer::writeIRect(const SkIRect& rect) {
     fWriter.write(&rect, sizeof(SkIRect));
 }

 void SkWriteBuffer::writeRect(const SkRect& rect) {
     fWriter.writeRect(rect);
 }

 void SkWriteBuffer::writeRegion(const SkRegion& region) {
     fWriter.writeRegion(region);
 }

 void SkWriteBuffer::writePath(const SkPath& path) {
     fWriter.writePath(path);
 }

 size_t SkWriteBuffer::writeStream(SkStream* stream, size_t length) {
     fWriter.write32(SkToU32(length));
     size_t bytesWritten = fWriter.readFromStream(stream, length);
     if (bytesWritten < length) {
         fWriter.reservePad(length - bytesWritten);
     }
     return bytesWritten;
 }

 bool SkWriteBuffer::writeToStream(SkWStream* stream) {
     return fWriter.writeToStream(stream);
 }

 static void write_encoded_bitmap(SkWriteBuffer* buffer, SkData* data,
                                  const SkIPoint& origin) {
     buffer->writeUInt(SkToU32(data->size()));
     buffer->getWriter32()->writePad(data->data(), data->size());
     buffer->write32(origin.fX);
     buffer->write32(origin.fY);
 }

 void SkWriteBuffer::writeBitmap(const SkBitmap& bitmap) {
     // Record the width and height. This way if readBitmap fails a dummy bitmap can be drawn at the
     // right size.
     this->writeInt(bitmap.width());
     this->writeInt(bitmap.height());

     // Record information about the bitmap in one of three ways, in order of priority:
     // 1. If there is an SkBitmapHeap, store it in the heap. The client can avoid serializing the
     //    bitmap entirely or serialize it later as desired. A boolean value of true will be written
     //    to the stream to signify that a heap was used.
     // 2. If there is a function for encoding bitmaps, use it to write an encoded version of the
     //    bitmap. After writing a boolean value of false, signifying that a heap was not used, write
     //    the size of the encoded data. A non-zero size signifies that encoded data was written.
     // 3. Call SkBitmap::flatten. After writing a boolean value of false, signifying that a heap was
     //    not used, write a zero to signify that the data was not encoded.
     bool useBitmapHeap = fBitmapHeap != NULL;
     // Write a bool: true if the SkBitmapHeap is to be used, in which case the reader must use an
     // SkBitmapHeapReader to read the SkBitmap. False if the bitmap was serialized another way.
     this->writeBool(useBitmapHeap);
     if (useBitmapHeap) {
         SkASSERT(NULL == fPixelSerializer);
         int32_t slot = fBitmapHeap->insert(bitmap);
         fWriter.write32(slot);
         // crbug.com/155875
         // The generation ID is not required information. We write it to prevent collisions
         // in SkFlatDictionary.  It is possible to get a collision when a previously
         // unflattened (i.e. stale) instance of a similar flattenable is in the dictionary
         // and the instance currently being written is re-using the same slot from the
         // bitmap heap.
         fWriter.write32(bitmap.getGenerationID());
         return;
     }

     SkPixelRef* pixelRef = bitmap.pixelRef();
     if (pixelRef) {
         // see if the pixelref already has an encoded version
         SkAutoDataUnref existingData(pixelRef->refEncodedData());
         if (existingData.get() != NULL) {
             // Assumes that if the client did not set a serializer, they are
             // happy to get the encoded data.
             if (!fPixelSerializer || fPixelSerializer->useEncodedData(existingData->data(),
                                                                       existingData->size())) {
                 write_encoded_bitmap(this, existingData, bitmap.pixelRefOrigin());
                 return;
             }
         }

         // see if the caller wants to manually encode
         if (fPixelSerializer) {
             SkASSERT(NULL == fBitmapHeap);
             SkAutoLockPixels alp(bitmap);
             SkAutoDataUnref data(fPixelSerializer->encodePixels(bitmap.info(),
                                                                 bitmap.getPixels(),
                                                                 bitmap.rowBytes()));
             if (data.get() != NULL) {
                 // if we have to "encode" the bitmap, then we assume there is no
                 // offset to share, since we are effectively creating a new pixelref
                 write_encoded_bitmap(this, data, SkIPoint::Make(0, 0));
                 return;
             }
         }
     }

     this->writeUInt(0); // signal raw pixels
     SkBitmap::WriteRawPixels(this, bitmap);
 }

 void SkWriteBuffer::writeTypeface(SkTypeface* obj) {
     if (NULL == obj || NULL == fTFSet) {
         fWriter.write32(0);
     } else {
         fWriter.write32(fTFSet->add(obj));
     }
 }

 SkFactorySet* SkWriteBuffer::setFactoryRecorder(SkFactorySet* rec) {
     SkRefCnt_SafeAssign(fFactorySet, rec);
     if (fNamedFactorySet != NULL) {
         fNamedFactorySet->unref();
         fNamedFactorySet = NULL;
     }
     return rec;
 }

 SkNamedFactorySet* SkWriteBuffer::setNamedFactoryRecorder(SkNamedFactorySet* rec) {
     SkRefCnt_SafeAssign(fNamedFactorySet, rec);
     if (fFactorySet != NULL) {
         fFactorySet->unref();
         fFactorySet = NULL;
     }
     return rec;
 }

 SkRefCntSet* SkWriteBuffer::setTypefaceRecorder(SkRefCntSet* rec) {
     SkRefCnt_SafeAssign(fTFSet, rec);
     return rec;
 }

 void SkWriteBuffer::setBitmapHeap(SkBitmapHeap* bitmapHeap) {
     SkRefCnt_SafeAssign(fBitmapHeap, bitmapHeap);
     if (bitmapHeap != NULL) {
         SkASSERT(NULL == fPixelSerializer);
         fPixelSerializer.reset(NULL);
     }
 }

 void SkWriteBuffer::setPixelSerializer(SkPixelSerializer* serializer) {
     fPixelSerializer.reset(serializer);
     if (serializer) {
         serializer->ref();
         SkASSERT(NULL == fBitmapHeap);
         SkSafeUnref(fBitmapHeap);
         fBitmapHeap = NULL;
     }
 }

 void SkWriteBuffer::writeFlattenable(const SkFlattenable* flattenable) {
     /*
      *  If we have a factoryset, then the first 32bits tell us...
      *       0: failure to write the flattenable
      *      >0: (1-based) index into the SkFactorySet or SkNamedFactorySet
      *  If we don't have a factoryset, then the first "ptr" is either the
      *  factory, or null for failure.
      *
      *  The distinction is important, since 0-index is 32bits (always), but a
      *  0-functionptr might be 32 or 64 bits.
      */
     if (NULL == flattenable) {
         if (this->isValidating()) {
             this->writeString("");
         } else if (fFactorySet != NULL || fNamedFactorySet != NULL) {
             this->write32(0);
         } else {
             this->writeFunctionPtr(NULL);
         }
         return;
     }

     SkFlattenable::Factory factory = flattenable->getFactory();
     SkASSERT(factory != NULL);

     /*
      *  We can write 1 of 3 versions of the flattenable:
      *  1.  function-ptr : this is the fastest for the reader, but assumes that
      *      the writer and reader are in the same process.
      *  2.  index into fFactorySet : This is assumes the writer will later
      *      resolve the function-ptrs into strings for its reader. SkPicture
      *      does exactly this, by writing a table of names (matching the indices)
      *      up front in its serialized form.
      *  3.  index into fNamedFactorySet. fNamedFactorySet will also store the
      *      name. SkGPipe uses this technique so it can write the name to its
      *      stream before writing the flattenable.
      */
     if (this->isValidating()) {
         this->writeString(flattenable->getTypeName());
     } else if (fFactorySet) {
         this->write32(fFactorySet->add(factory));
     } else if (fNamedFactorySet) {
         int32_t index = fNamedFactorySet->find(factory);
         this->write32(index);
         if (0 == index) {
             return;
         }
     } else {
         this->writeFunctionPtr((void*)factory);
     }

     // make room for the size of the flattened object
     (void)fWriter.reserve(sizeof(uint32_t));
     // record the current size, so we can subtract after the object writes.
     size_t offset = fWriter.bytesWritten();
     // now flatten the object
     flattenable->flatten(*this);
     size_t objSize = fWriter.bytesWritten() - offset;
     // record the obj's size
     fWriter.overwriteTAt(offset - sizeof(uint32_t), SkToU32(objSize));
 }

	/*
	* Copyright 2012 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "SkWriteBuffer.h"
	#include "SkBitmap.h"
	#include "SkBitmapHeap.h"
	#include "SkData.h"
	#include "SkPixelRef.h"
	#include "SkPtrRecorder.h"
	#include "SkStream.h"
	#include "SkTypeface.h"

	SkWriteBuffer::SkWriteBuffer(uint32_t flags)
	: fFlags(flags)
	, fFactorySet(NULL)
	, fNamedFactorySet(NULL)
	, fBitmapHeap(NULL)
	, fTFSet(NULL) {
	}

	SkWriteBuffer::SkWriteBuffer(void* storage, size_t storageSize, uint32_t flags)
	: fFlags(flags)
	, fFactorySet(NULL)
	, fNamedFactorySet(NULL)
	, fWriter(storage, storageSize)
	, fBitmapHeap(NULL)
	, fTFSet(NULL) {
	}

	SkWriteBuffer::~SkWriteBuffer() {
	SkSafeUnref(fFactorySet);
	SkSafeUnref(fNamedFactorySet);
	SkSafeUnref(fBitmapHeap);
	SkSafeUnref(fTFSet);
	}

	void SkWriteBuffer::writeByteArray(const void* data, size_t size) {
	fWriter.write32(SkToU32(size));
	fWriter.writePad(data, size);
	}

	void SkWriteBuffer::writeBool(bool value) {
	fWriter.writeBool(value);
	}

	void SkWriteBuffer::writeFixed(SkFixed value) {
	fWriter.write32(value);
	}

	void SkWriteBuffer::writeScalar(SkScalar value) {
	fWriter.writeScalar(value);
	}

	void SkWriteBuffer::writeScalarArray(const SkScalar* value, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(value, count * sizeof(SkScalar));
	}

	void SkWriteBuffer::writeInt(int32_t value) {
	fWriter.write32(value);
	}

	void SkWriteBuffer::writeIntArray(const int32_t* value, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(value, count * sizeof(int32_t));
	}

	void SkWriteBuffer::writeUInt(uint32_t value) {
	fWriter.write32(value);
	}

	void SkWriteBuffer::write32(int32_t value) {
	fWriter.write32(value);
	}

	void SkWriteBuffer::writeString(const char* value) {
	fWriter.writeString(value);
	}

	void SkWriteBuffer::writeEncodedString(const void* value, size_t byteLength,
	SkPaint::TextEncoding encoding) {
	fWriter.writeInt(encoding);
	fWriter.writeInt(SkToU32(byteLength));
	fWriter.write(value, byteLength);
	}


	void SkWriteBuffer::writeColor(const SkColor& color) {
	fWriter.write32(color);
	}

	void SkWriteBuffer::writeColorArray(const SkColor* color, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(color, count * sizeof(SkColor));
	}

	void SkWriteBuffer::writePoint(const SkPoint& point) {
	fWriter.writeScalar(point.fX);
	fWriter.writeScalar(point.fY);
	}

	void SkWriteBuffer::writePointArray(const SkPoint* point, uint32_t count) {
	fWriter.write32(count);
	fWriter.write(point, count * sizeof(SkPoint));
	}

	void SkWriteBuffer::writeMatrix(const SkMatrix& matrix) {
	fWriter.writeMatrix(matrix);
	}

	void SkWriteBuffer::writeIRect(const SkIRect& rect) {
	fWriter.write(&rect, sizeof(SkIRect));
	}

	void SkWriteBuffer::writeRect(const SkRect& rect) {
	fWriter.writeRect(rect);
	}

	void SkWriteBuffer::writeRegion(const SkRegion& region) {
	fWriter.writeRegion(region);
	}

	void SkWriteBuffer::writePath(const SkPath& path) {
	fWriter.writePath(path);
	}

	size_t SkWriteBuffer::writeStream(SkStream* stream, size_t length) {
	fWriter.write32(SkToU32(length));
	size_t bytesWritten = fWriter.readFromStream(stream, length);
	if (bytesWritten < length) {
	fWriter.reservePad(length - bytesWritten);
	}
	return bytesWritten;
	}

	bool SkWriteBuffer::writeToStream(SkWStream* stream) {
	return fWriter.writeToStream(stream);
	}

	static void write_encoded_bitmap(SkWriteBuffer* buffer, SkData* data,
	const SkIPoint& origin) {
	buffer->writeUInt(SkToU32(data->size()));
	buffer->getWriter32()->writePad(data->data(), data->size());
	buffer->write32(origin.fX);
	buffer->write32(origin.fY);
	}

	void SkWriteBuffer::writeBitmap(const SkBitmap& bitmap) {
	// Record the width and height. This way if readBitmap fails a dummy bitmap can be drawn at the
	// right size.
	this->writeInt(bitmap.width());
	this->writeInt(bitmap.height());

	// Record information about the bitmap in one of three ways, in order of priority:
	// 1. If there is an SkBitmapHeap, store it in the heap. The client can avoid serializing the
	// bitmap entirely or serialize it later as desired. A boolean value of true will be written
	// to the stream to signify that a heap was used.
	// 2. If there is a function for encoding bitmaps, use it to write an encoded version of the
	// bitmap. After writing a boolean value of false, signifying that a heap was not used, write
	// the size of the encoded data. A non-zero size signifies that encoded data was written.
	// 3. Call SkBitmap::flatten. After writing a boolean value of false, signifying that a heap was
	// not used, write a zero to signify that the data was not encoded.
	bool useBitmapHeap = fBitmapHeap != NULL;
	// Write a bool: true if the SkBitmapHeap is to be used, in which case the reader must use an
	// SkBitmapHeapReader to read the SkBitmap. False if the bitmap was serialized another way.
	this->writeBool(useBitmapHeap);
	if (useBitmapHeap) {
	SkASSERT(NULL == fPixelSerializer);
	int32_t slot = fBitmapHeap->insert(bitmap);
	fWriter.write32(slot);
	// crbug.com/155875
	// The generation ID is not required information. We write it to prevent collisions
	// in SkFlatDictionary. It is possible to get a collision when a previously
	// unflattened (i.e. stale) instance of a similar flattenable is in the dictionary
	// and the instance currently being written is re-using the same slot from the
	// bitmap heap.
	fWriter.write32(bitmap.getGenerationID());
	return;
	}

	SkPixelRef* pixelRef = bitmap.pixelRef();
	if (pixelRef) {
	// see if the pixelref already has an encoded version
	SkAutoDataUnref existingData(pixelRef->refEncodedData());
	if (existingData.get() != NULL) {
	// Assumes that if the client did not set a serializer, they are
	// happy to get the encoded data.
	if (!fPixelSerializer \|\| fPixelSerializer->useEncodedData(existingData->data(),
	existingData->size())) {
	write_encoded_bitmap(this, existingData, bitmap.pixelRefOrigin());
	return;
	}
	}

	// see if the caller wants to manually encode
	if (fPixelSerializer) {
	SkASSERT(NULL == fBitmapHeap);
	SkAutoLockPixels alp(bitmap);
	SkAutoDataUnref data(fPixelSerializer->encodePixels(bitmap.info(),
	bitmap.getPixels(),
	bitmap.rowBytes()));
	if (data.get() != NULL) {
	// if we have to "encode" the bitmap, then we assume there is no
	// offset to share, since we are effectively creating a new pixelref
	write_encoded_bitmap(this, data, SkIPoint::Make(0, 0));
	return;
	}
	}
	}

	this->writeUInt(0); // signal raw pixels
	SkBitmap::WriteRawPixels(this, bitmap);
	}

	void SkWriteBuffer::writeTypeface(SkTypeface* obj) {
	if (NULL == obj \|\| NULL == fTFSet) {
	fWriter.write32(0);
	} else {
	fWriter.write32(fTFSet->add(obj));
	}
	}

	SkFactorySet* SkWriteBuffer::setFactoryRecorder(SkFactorySet* rec) {
	SkRefCnt_SafeAssign(fFactorySet, rec);
	if (fNamedFactorySet != NULL) {
	fNamedFactorySet->unref();
	fNamedFactorySet = NULL;
	}
	return rec;
	}

	SkNamedFactorySet* SkWriteBuffer::setNamedFactoryRecorder(SkNamedFactorySet* rec) {
	SkRefCnt_SafeAssign(fNamedFactorySet, rec);
	if (fFactorySet != NULL) {
	fFactorySet->unref();
	fFactorySet = NULL;
	}
	return rec;
	}

	SkRefCntSet* SkWriteBuffer::setTypefaceRecorder(SkRefCntSet* rec) {
	SkRefCnt_SafeAssign(fTFSet, rec);
	return rec;
	}

	void SkWriteBuffer::setBitmapHeap(SkBitmapHeap* bitmapHeap) {
	SkRefCnt_SafeAssign(fBitmapHeap, bitmapHeap);
	if (bitmapHeap != NULL) {
	SkASSERT(NULL == fPixelSerializer);
	fPixelSerializer.reset(NULL);
	}
	}

	void SkWriteBuffer::setPixelSerializer(SkPixelSerializer* serializer) {
	fPixelSerializer.reset(serializer);
	if (serializer) {
	serializer->ref();
	SkASSERT(NULL == fBitmapHeap);
	SkSafeUnref(fBitmapHeap);
	fBitmapHeap = NULL;
	}
	}

	void SkWriteBuffer::writeFlattenable(const SkFlattenable* flattenable) {
	/*
	* If we have a factoryset, then the first 32bits tell us...
	* 0: failure to write the flattenable
	* >0: (1-based) index into the SkFactorySet or SkNamedFactorySet
	* If we don't have a factoryset, then the first "ptr" is either the
	* factory, or null for failure.
	*
	* The distinction is important, since 0-index is 32bits (always), but a
	* 0-functionptr might be 32 or 64 bits.
	*/
	if (NULL == flattenable) {
	if (this->isValidating()) {
	this->writeString("");
	} else if (fFactorySet != NULL \|\| fNamedFactorySet != NULL) {
	this->write32(0);
	} else {
	this->writeFunctionPtr(NULL);
	}
	return;
	}

	SkFlattenable::Factory factory = flattenable->getFactory();
	SkASSERT(factory != NULL);

	/*
	* We can write 1 of 3 versions of the flattenable:
	* 1. function-ptr : this is the fastest for the reader, but assumes that
	* the writer and reader are in the same process.
	* 2. index into fFactorySet : This is assumes the writer will later
	* resolve the function-ptrs into strings for its reader. SkPicture
	* does exactly this, by writing a table of names (matching the indices)
	* up front in its serialized form.
	* 3. index into fNamedFactorySet. fNamedFactorySet will also store the
	* name. SkGPipe uses this technique so it can write the name to its
	* stream before writing the flattenable.
	*/
	if (this->isValidating()) {
	this->writeString(flattenable->getTypeName());
	} else if (fFactorySet) {
	this->write32(fFactorySet->add(factory));
	} else if (fNamedFactorySet) {
	int32_t index = fNamedFactorySet->find(factory);
	this->write32(index);
	if (0 == index) {
	return;
	}
	} else {
	this->writeFunctionPtr((void*)factory);
	}

	// make room for the size of the flattened object
	(void)fWriter.reserve(sizeof(uint32_t));
	// record the current size, so we can subtract after the object writes.
	size_t offset = fWriter.bytesWritten();
	// now flatten the object
	flattenable->flatten(*this);
	size_t objSize = fWriter.bytesWritten() - offset;
	// record the obj's size
	fWriter.overwriteTAt(offset - sizeof(uint32_t), SkToU32(objSize));
	}