1 /*
2  * Copyright 2011 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #ifndef SkReadBuffer_DEFINED
9 #define SkReadBuffer_DEFINED
10 
11 #include "SkBitmapHeap.h"
12 #include "SkColorFilter.h"
13 #include "SkData.h"
14 #include "SkDrawLooper.h"
15 #include "SkImageFilter.h"
16 #include "SkMaskFilter.h"
17 #include "SkPath.h"
18 #include "SkPathEffect.h"
19 #include "SkPicture.h"
20 #include "SkRasterizer.h"
21 #include "SkReadBuffer.h"
22 #include "SkReader32.h"
23 #include "SkRefCnt.h"
24 #include "SkShader.h"
25 #include "SkWriteBuffer.h"
26 #include "SkXfermode.h"
27 
28 class SkBitmap;
29 
30 #if defined(SK_DEBUG) && defined(SK_BUILD_FOR_MAC)
31     #define DEBUG_NON_DETERMINISTIC_ASSERT
32 #endif
33 
34 class SkReadBuffer {
35 public:
36     SkReadBuffer();
37     SkReadBuffer(const void* data, size_t size);
38     SkReadBuffer(SkStream* stream);
39     virtual ~SkReadBuffer();
40 
41     enum Version {
42         /*
43         kFilterLevelIsEnum_Version         = 23,
44         kGradientFlippedFlag_Version       = 24,
45         kDashWritesPhaseIntervals_Version  = 25,
46         kColorShaderNoBool_Version         = 26,
47         kNoUnitMappers_Version             = 27,
48         kNoMoreBitmapFlatten_Version       = 28,
49         kSimplifyLocalMatrix_Version       = 30,
50         kImageFilterUniqueID_Version       = 31,
51         kRemoveAndroidPaintOpts_Version    = 32,
52         kFlattenCreateProc_Version         = 33,
53         */
54         kRemoveColorTableAlpha_Version     = 36,
55         kDropShadowMode_Version            = 37,
56         kPictureImageFilterResolution_Version = 38,
57         kPictureImageFilterLevel_Version   = 39,
58         kImageFilterNoUniqueID_Version     = 40,
59         kBitmapSourceFilterQuality_Version = 41
60     };
61 
62     /**
63      *  Returns true IFF the version is older than the specified version.
64      */
isVersionLT(Version targetVersion)65     bool isVersionLT(Version targetVersion) const {
66         SkASSERT(targetVersion > 0);
67         return fVersion > 0 && fVersion < targetVersion;
68     }
69 
70     /** This may be called at most once; most clients of SkReadBuffer should not mess with it. */
setVersion(int version)71     void setVersion(int version) {
72         SkASSERT(0 == fVersion || version == fVersion);
73         fVersion = version;
74     }
75 
76     enum Flags {
77         kCrossProcess_Flag  = 1 << 0,
78         kScalarIsFloat_Flag = 1 << 1,
79         kPtrIs64Bit_Flag    = 1 << 2,
80         kValidation_Flag    = 1 << 3,
81     };
82 
setFlags(uint32_t flags)83     void setFlags(uint32_t flags) { fFlags = flags; }
getFlags()84     uint32_t getFlags() const { return fFlags; }
85 
isCrossProcess()86     bool isCrossProcess() const {
87         return this->isValidating() || SkToBool(fFlags & kCrossProcess_Flag);
88     }
isScalarFloat()89     bool isScalarFloat() const { return SkToBool(fFlags & kScalarIsFloat_Flag); }
isPtr64Bit()90     bool isPtr64Bit() const { return SkToBool(fFlags & kPtrIs64Bit_Flag); }
isValidating()91     bool isValidating() const { return SkToBool(fFlags & kValidation_Flag); }
92 
getReader32()93     SkReader32* getReader32() { return &fReader; }
94 
size()95     size_t size() { return fReader.size(); }
offset()96     size_t offset() { return fReader.offset(); }
eof()97     bool eof() { return fReader.eof(); }
skip(size_t size)98     virtual const void* skip(size_t size) { return fReader.skip(size); }
readFunctionPtr()99     void* readFunctionPtr() { return fReader.readPtr(); }
100 
101     // primitives
102     virtual bool readBool();
103     virtual SkColor readColor();
104     virtual SkFixed readFixed();
105     virtual int32_t readInt();
106     virtual SkScalar readScalar();
107     virtual uint32_t readUInt();
108     virtual int32_t read32();
109 
110     // strings -- the caller is responsible for freeing the string contents
111     virtual void readString(SkString* string);
112     virtual void* readEncodedString(size_t* length, SkPaint::TextEncoding encoding);
113 
114     // common data structures
115     virtual void readPoint(SkPoint* point);
readPoint()116     SkPoint readPoint() { SkPoint p; this->readPoint(&p); return p; }
117     virtual void readMatrix(SkMatrix* matrix);
118     virtual void readIRect(SkIRect* rect);
119     virtual void readRect(SkRect* rect);
120     virtual void readRegion(SkRegion* region);
121 
122     virtual void readPath(SkPath* path);
readPaint(SkPaint * paint)123     void readPaint(SkPaint* paint) { paint->unflatten(*this); }
124 
125     virtual SkFlattenable* readFlattenable(SkFlattenable::Type);
readFlattenable()126     template <typename T> T* readFlattenable() {
127         return (T*) this->readFlattenable(T::GetFlattenableType());
128     }
readColorFilter()129     SkColorFilter* readColorFilter() { return this->readFlattenable<SkColorFilter>(); }
readDrawLooper()130     SkDrawLooper*  readDrawLooper()  { return this->readFlattenable<SkDrawLooper>(); }
readImageFilter()131     SkImageFilter* readImageFilter() { return this->readFlattenable<SkImageFilter>(); }
readMaskFilter()132     SkMaskFilter*  readMaskFilter()  { return this->readFlattenable<SkMaskFilter>(); }
readPathEffect()133     SkPathEffect*  readPathEffect()  { return this->readFlattenable<SkPathEffect>(); }
readRasterizer()134     SkRasterizer*  readRasterizer()  { return this->readFlattenable<SkRasterizer>(); }
readShader()135     SkShader*      readShader()      { return this->readFlattenable<SkShader>(); }
readXfermode()136     SkXfermode*    readXfermode()    { return this->readFlattenable<SkXfermode>(); }
137 
138     /**
139      *  Like readFlattenable() but explicitly just skips the data that was written for the
140      *  flattenable (or the sentinel that there wasn't one).
141      */
142     virtual void skipFlattenable();
143 
144     // binary data and arrays
145     virtual bool readByteArray(void* value, size_t size);
146     virtual bool readColorArray(SkColor* colors, size_t size);
147     virtual bool readIntArray(int32_t* values, size_t size);
148     virtual bool readPointArray(SkPoint* points, size_t size);
149     virtual bool readScalarArray(SkScalar* values, size_t size);
150 
readByteArrayAsData()151     SkData* readByteArrayAsData() {
152         size_t len = this->getArrayCount();
153         if (!this->validateAvailable(len)) {
154             return SkData::NewEmpty();
155         }
156         void* buffer = sk_malloc_throw(len);
157         this->readByteArray(buffer, len);
158         return SkData::NewFromMalloc(buffer, len);
159     }
160 
161     // helpers to get info about arrays and binary data
162     virtual uint32_t getArrayCount();
163 
164     /**
165      *  Returns false if the bitmap could not be completely read. In that case, it will be set
166      *  to have width/height, but no pixels.
167      */
168     bool readBitmap(SkBitmap* bitmap);
169 
170     virtual SkTypeface* readTypeface();
171 
setBitmapStorage(SkBitmapHeapReader * bitmapStorage)172     void setBitmapStorage(SkBitmapHeapReader* bitmapStorage) {
173         SkRefCnt_SafeAssign(fBitmapStorage, bitmapStorage);
174     }
175 
setTypefaceArray(SkTypeface * array[],int count)176     void setTypefaceArray(SkTypeface* array[], int count) {
177         fTFArray = array;
178         fTFCount = count;
179     }
180 
181     /**
182      *  Call this with a pre-loaded array of Factories, in the same order as
183      *  were created/written by the writer. SkPicture uses this.
184      */
setFactoryPlayback(SkFlattenable::Factory array[],int count)185     void setFactoryPlayback(SkFlattenable::Factory array[], int count) {
186         fFactoryTDArray = NULL;
187         fFactoryArray = array;
188         fFactoryCount = count;
189     }
190 
191     /**
192      *  Call this with an initially empty array, so the reader can cache each
193      *  factory it sees by name. Used by the pipe code in conjunction with
194      *  SkWriteBuffer::setNamedFactoryRecorder.
195      */
setFactoryArray(SkTDArray<SkFlattenable::Factory> * array)196     void setFactoryArray(SkTDArray<SkFlattenable::Factory>* array) {
197         fFactoryTDArray = array;
198         fFactoryArray = NULL;
199         fFactoryCount = 0;
200     }
201 
202     /**
203      *  Provide a function to decode an SkBitmap from encoded data. Only used if the writer
204      *  encoded the SkBitmap. If the proper decoder cannot be used, a red bitmap with the
205      *  appropriate size will be used.
206      */
setBitmapDecoder(SkPicture::InstallPixelRefProc bitmapDecoder)207     void setBitmapDecoder(SkPicture::InstallPixelRefProc bitmapDecoder) {
208         fBitmapDecoder = bitmapDecoder;
209     }
210 
211     // Default impelementations don't check anything.
validate(bool isValid)212     virtual bool validate(bool isValid) { return true; }
isValid()213     virtual bool isValid() const { return true; }
validateAvailable(size_t size)214     virtual bool validateAvailable(size_t size) { return true; }
215 
216 protected:
217     SkReader32 fReader;
218 
219 private:
220     bool readArray(void* value, size_t size, size_t elementSize);
221 
222     uint32_t fFlags;
223     int fVersion;
224 
225     void* fMemoryPtr;
226 
227     SkBitmapHeapReader* fBitmapStorage;
228     SkTypeface** fTFArray;
229     int        fTFCount;
230 
231     SkTDArray<SkFlattenable::Factory>* fFactoryTDArray;
232     SkFlattenable::Factory* fFactoryArray;
233     int                     fFactoryCount;
234 
235     SkPicture::InstallPixelRefProc fBitmapDecoder;
236 
237 #ifdef DEBUG_NON_DETERMINISTIC_ASSERT
238     // Debugging counter to keep track of how many bitmaps we
239     // have decoded.
240     int fDecodedBitmapIndex;
241 #endif // DEBUG_NON_DETERMINISTIC_ASSERT
242 };
243 
244 #endif // SkReadBuffer_DEFINED
245