Refactor read and write buffers.

include/core/SkReadBuffer.h

+
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkReadBuffer_DEFINED
+#define SkReadBuffer_DEFINED
+
+#include "SkBitmapHeap.h"
+#include "SkColorFilter.h"
+#include "SkData.h"
+#include "SkDrawLooper.h"
+#include "SkImageFilter.h"
+#include "SkMaskFilter.h"
+#include "SkPath.h"
+#include "SkPathEffect.h"
+#include "SkPicture.h"
+#include "SkPixelRef.h"
+#include "SkRasterizer.h"
+#include "SkReadBuffer.h"
+#include "SkReader32.h"
+#include "SkRefCnt.h"
+#include "SkShader.h"
+#include "SkUnitMapper.h"
+#include "SkWriteBuffer.h"
+#include "SkXfermode.h"
+
+class SkBitmap;
+
+#if defined(SK_DEBUG) && defined(SK_BUILD_FOR_MAC)
+    #define DEBUG_NON_DETERMINISTIC_ASSERT
+#endif
+
+class SkReadBuffer {
+public:
+    SkReadBuffer();
+    SkReadBuffer(const void* data, size_t size);
+    SkReadBuffer(SkStream* stream);
+    virtual ~SkReadBuffer();
+
+    enum Flags {
+        kCrossProcess_Flag  = 1 << 0,
+        kScalarIsFloat_Flag = 1 << 1,
+        kPtrIs64Bit_Flag    = 1 << 2,
+        kValidation_Flag    = 1 << 3,
+    };
+
+    void setFlags(uint32_t flags) { fFlags = flags; }
+    uint32_t getFlags() const { return fFlags; }
+
+    bool isCrossProcess() const {
+        return this->isValidating() || SkToBool(fFlags & kCrossProcess_Flag);
+    }
+    bool isScalarFloat() const { return SkToBool(fFlags & kScalarIsFloat_Flag); }
+    bool isPtr64Bit() const { return SkToBool(fFlags & kPtrIs64Bit_Flag); }
+    bool isValidating() const { return SkToBool(fFlags & kValidation_Flag); }
+
+    SkReader32* getReader32() { return &fReader; }
+
+    uint32_t size() { return fReader.size(); }
+    uint32_t offset() { return fReader.offset(); }
+    bool eof() { return fReader.eof(); }
+    const void* skip(size_t size) { return fReader.skip(size); }
+
+    // primitives
+    virtual bool readBool();
+    virtual SkColor readColor();
+    virtual SkFixed readFixed();
+    virtual int32_t readInt();
+    virtual SkScalar readScalar();
+    virtual uint32_t readUInt();
+    virtual int32_t read32();
+
+    void* readFunctionPtr() {
+        void* ptr;
+        this->readByteArray(&ptr, sizeof(ptr));
+        return ptr;
+    }
+
+    // strings -- the caller is responsible for freeing the string contents
+    virtual void readString(SkString* string);
+    virtual void* readEncodedString(size_t* length, SkPaint::TextEncoding encoding);
+
+    // common data structures
+    virtual void readPoint(SkPoint* point);
+    SkPoint readPoint() { SkPoint p; this->readPoint(&p); return p; }
+    virtual void readMatrix(SkMatrix* matrix);
+    virtual void readIRect(SkIRect* rect);
+    virtual void readRect(SkRect* rect);
+    virtual void readRegion(SkRegion* region);
+    virtual void readPath(SkPath* path);
+    void readPaint(SkPaint* paint) { paint->unflatten(*this); }
+
+    virtual SkFlattenable* readFlattenable(SkFlattenable::Type);
+    template <typename T> T* readFlattenable() {
+        return (T*) this->readFlattenable(T::GetFlattenableType());
+    }
+    SkColorFilter* readColorFilter() { return this->readFlattenable<SkColorFilter>(); }
+    SkDrawLooper*  readDrawLooper()  { return this->readFlattenable<SkDrawLooper>(); }
+    SkImageFilter* readImageFilter() { return this->readFlattenable<SkImageFilter>(); }
+    SkMaskFilter*  readMaskFilter()  { return this->readFlattenable<SkMaskFilter>(); }
+    SkPathEffect*  readPathEffect()  { return this->readFlattenable<SkPathEffect>(); }
+    SkPixelRef*    readPixelRef()    { return this->readFlattenable<SkPixelRef>(); }
+    SkRasterizer*  readRasterizer()  { return this->readFlattenable<SkRasterizer>(); }
+    SkShader*      readShader()      { return this->readFlattenable<SkShader>(); }
+    SkUnitMapper*  readUnitMapper()  { return this->readFlattenable<SkUnitMapper>(); }
+    SkXfermode*    readXfermode()    { return this->readFlattenable<SkXfermode>(); }
+
+
+    // binary data and arrays
+    virtual bool readByteArray(void* value, size_t size);
+    virtual bool readColorArray(SkColor* colors, size_t size);
+    virtual bool readIntArray(int32_t* values, size_t size);
+    virtual bool readPointArray(SkPoint* points, size_t size);
+    virtual bool readScalarArray(SkScalar* values, size_t size);
+
+    SkData* readByteArrayAsData() {
+        size_t len = this->getArrayCount();
+        if (!this->validateAvailable(len)) {
+            return SkData::NewEmpty();
+        }
+        void* buffer = sk_malloc_throw(len);
+        this->readByteArray(buffer, len);
+        return SkData::NewFromMalloc(buffer, len);
+    }
+
+    // helpers to get info about arrays and binary data
+    virtual uint32_t getArrayCount();
+
+    virtual void readBitmap(SkBitmap* bitmap);
+    virtual SkTypeface* readTypeface();
+
+    void setBitmapStorage(SkBitmapHeapReader* bitmapStorage) {
+        SkRefCnt_SafeAssign(fBitmapStorage, bitmapStorage);
+    }
+
+    void setTypefaceArray(SkTypeface* array[], int count) {
+        fTFArray = array;
+        fTFCount = count;
+    }
+
+    /**
+     *  Call this with a pre-loaded array of Factories, in the same order as
+     *  were created/written by the writer. SkPicture uses this.
+     */
+    void setFactoryPlayback(SkFlattenable::Factory array[], int count) {
+        fFactoryTDArray = NULL;
+        fFactoryArray = array;
+        fFactoryCount = count;
+    }
+
+    /**
+     *  Call this with an initially empty array, so the reader can cache each
+     *  factory it sees by name. Used by the pipe code in conjunction with
+     *  SkWriteBuffer::setNamedFactoryRecorder.
+     */
+    void setFactoryArray(SkTDArray<SkFlattenable::Factory>* array) {
+        fFactoryTDArray = array;
+        fFactoryArray = NULL;
+        fFactoryCount = 0;
+    }
+
+    /**
+     *  Provide a function to decode an SkBitmap from encoded data. Only used if the writer
+     *  encoded the SkBitmap. If the proper decoder cannot be used, a red bitmap with the
+     *  appropriate size will be used.
+     */
+    void setBitmapDecoder(SkPicture::InstallPixelRefProc bitmapDecoder) {
+        fBitmapDecoder = bitmapDecoder;
+    }
+
+    // Default impelementations don't check anything.
+    virtual bool validate(bool isValid) { return true; }
+    virtual bool isValid() const { return true; }
+    virtual bool validateAvailable(size_t size) { return true; }
+
+private:
+    bool readArray(void* value, size_t size, size_t elementSize);
+
+    uint32_t fFlags;
+
+    SkReader32 fReader;
+    void* fMemoryPtr;
+
+    SkBitmapHeapReader* fBitmapStorage;
+    SkTypeface** fTFArray;
+    int        fTFCount;
+
+    SkTDArray<SkFlattenable::Factory>* fFactoryTDArray;
+    SkFlattenable::Factory* fFactoryArray;
+    int                     fFactoryCount;
+
+    SkPicture::InstallPixelRefProc fBitmapDecoder;
+
+#ifdef DEBUG_NON_DETERMINISTIC_ASSERT
+    // Debugging counter to keep track of how many bitmaps we
+    // have decoded.
+    int fDecodedBitmapIndex;
+#endif // DEBUG_NON_DETERMINISTIC_ASSERT
+};
+
+#endif // SkReadBuffer_DEFINED