Changes to preserve backwards compatibility for serialization

Skia's serialize methods are not intended for backwards compatibility,
but the browser used it to implement saved pages. As a result the
revision of Skia used for ICS (r1562) is not compatible with the
revision of Skia used in JB (r3000+). This CL attempts to make pages
saved in ICS render in JB while still allowing JB pages to be saved
and displayed.

bug: 6025365
Change-Id: I9983517b46d2dedf31c6d90f48f6cf00ec042bc2

10 files changed, 89 insertions, 12 deletions

diff --git a/include/core/SkFlattenable.h b/include/core/SkFlattenable.h
index a66638e..34ca34e 100644
--- a/include/core/SkFlattenable.h
+++ b/include/core/SkFlattenable.h
@@ -161,6 +161,9 @@ public:
     void* readFunctionPtr();
     SkFlattenable* readFlattenable();
     
+    void setPictureVersion(uint32_t version) { fPictureVersion = version; }
+    uint32_t getPictureVersion() { return fPictureVersion; }
+
 private:
     SkRefCnt** fRCArray;
     int        fRCCount;
@@ -172,6 +175,8 @@ private:
     SkFlattenable::Factory* fFactoryArray;
     int                     fFactoryCount;
     
+    uint32_t fPictureVersion;
+
     typedef SkReader32 INHERITED;
 };
 
diff --git a/include/core/SkUserConfig.h b/include/core/SkUserConfig.h
index b409e82..4bcf2e3 100644
--- a/include/core/SkUserConfig.h
+++ b/include/core/SkUserConfig.h
@@ -41,6 +41,9 @@
 // ANDROID Specific changes - NO NOT CHECK BACK INTO code.google.com/p/skia
 //
 
+#define PICTURE_VERSION_ICS 1 // r1562 of Skia
+#define PICTURE_VERSION_JB  2
+
 // do this build check for other tools that still read this header
 #ifdef ANDROID
     #include <utils/misc.h>
diff --git a/src/core/SkFlattenable.cpp b/src/core/SkFlattenable.cpp
index 59a262a..131cf4f 100644
--- a/src/core/SkFlattenable.cpp
+++ b/src/core/SkFlattenable.cpp
@@ -58,6 +58,7 @@ SkFlattenableReadBuffer::SkFlattenableReadBuffer() {
     fFactoryTDArray = NULL;
     fFactoryArray = NULL;
     fFactoryCount = 0;
+    fPictureVersion = PICTURE_VERSION_JB;
 }
 
 SkFlattenableReadBuffer::SkFlattenableReadBuffer(const void* data) :
@@ -71,6 +72,7 @@ SkFlattenableReadBuffer::SkFlattenableReadBuffer(const void* data) :
     fFactoryTDArray = NULL;
     fFactoryArray = NULL;
     fFactoryCount = 0;
+    fPictureVersion = PICTURE_VERSION_JB;
 }
 
 SkFlattenableReadBuffer::SkFlattenableReadBuffer(const void* data, size_t size)
@@ -84,6 +86,7 @@ SkFlattenableReadBuffer::SkFlattenableReadBuffer(const void* data, size_t size)
     fFactoryTDArray = NULL;
     fFactoryArray = NULL;
     fFactoryCount = 0;
+    fPictureVersion = PICTURE_VERSION_JB;
 }
 
 SkTypeface* SkFlattenableReadBuffer::readTypeface() {
@@ -110,6 +113,43 @@ SkRefCnt* SkFlattenableReadBuffer::readRefCnt() {
 }
 
 SkFlattenable* SkFlattenableReadBuffer::readFlattenable() {
+
+    if(fPictureVersion == PICTURE_VERSION_ICS) {
+        SkFlattenable::Factory factory = NULL;
+
+        if (fFactoryCount > 0) {
+            uint32_t index = this->readU32();
+            if (index > 0) {
+                index -= 1;
+                SkASSERT(index < (unsigned)fFactoryCount);
+                factory = fFactoryArray[index];
+                // if we recorded an index, but failed to get a factory, we need
+                // to skip the flattened data in the buffer
+                if (NULL == factory) {
+                    uint32_t size = this->readU32();
+                    this->skip(size);
+                    // fall through and return NULL for the object
+                }
+            }
+        } else {
+            factory = (SkFlattenable::Factory)readFunctionPtr();
+        }
+
+        SkFlattenable* obj = NULL;
+        if (factory) {
+            uint32_t sizeRecorded = this->readU32();
+            uint32_t offset = this->offset();
+            obj = (*factory)(*this);
+            // check that we read the amount we expected
+            uint32_t sizeRead = this->offset() - offset;
+            if (sizeRecorded != sizeRead) {
+                // we could try to fix up the offset...
+                sk_throw();
+            }
+        }
+        return obj;
+    }
+
     SkFlattenable::Factory factory = NULL;
 
     if (fFactoryCount > 0) {
diff --git a/src/core/SkPaint.cpp b/src/core/SkPaint.cpp
index a6d30c9..ea5e876 100644
--- a/src/core/SkPaint.cpp
+++ b/src/core/SkPaint.cpp
@@ -1722,11 +1722,16 @@ void SkPaint::unflatten(SkFlattenableReadBuffer& buffer) {
     uint32_t tmp = *pod++;
     this->setFlags(tmp >> 16);
 
-    // hinting added later. 0 in this nibble means use the default.
-    uint32_t hinting = (tmp >> 12) & 0xF;
-    this->setHinting(0 == hinting ? kNormal_Hinting : static_cast<Hinting>(hinting-1));
+    if (buffer.getPictureVersion() == PICTURE_VERSION_ICS) {
+        this->setTextAlign(static_cast<Align>((tmp >> 8) & 0xFF));
+        this->setHinting(kNormal_Hinting);
+    } else {
+        // hinting added later. 0 in this nibble means use the default.
+        uint32_t hinting = (tmp >> 12) & 0xF;
+        this->setHinting(0 == hinting ? kNormal_Hinting : static_cast<Hinting>(hinting-1));
 
-    this->setTextAlign(static_cast<Align>((tmp >> 8) & 0xF));
+        this->setTextAlign(static_cast<Align>((tmp >> 8) & 0xF));
+    }
 
     uint8_t flatFlags = tmp & 0xFF;
 
@@ -1750,7 +1755,10 @@ void SkPaint::unflatten(SkFlattenableReadBuffer& buffer) {
         SkSafeUnref(this->setColorFilter((SkColorFilter*) buffer.readFlattenable()));
         SkSafeUnref(this->setRasterizer((SkRasterizer*) buffer.readFlattenable()));
         SkSafeUnref(this->setLooper((SkDrawLooper*) buffer.readFlattenable()));
-        SkSafeUnref(this->setImageFilter((SkImageFilter*) buffer.readFlattenable()));
+        if (buffer.getPictureVersion() != PICTURE_VERSION_ICS)
+            SkSafeUnref(this->setImageFilter((SkImageFilter*) buffer.readFlattenable()));
+        else
+            this->setImageFilter(NULL);
     } else {
         this->setPathEffect(NULL);
         this->setShader(NULL);
diff --git a/src/core/SkPicture.cpp b/src/core/SkPicture.cpp
index a3b7396..6aaaf2d 100644
--- a/src/core/SkPicture.cpp
+++ b/src/core/SkPicture.cpp
@@ -192,7 +192,9 @@ void SkPicture::draw(SkCanvas* surface) {
 #define PICTURE_VERSION     1
 
 SkPicture::SkPicture(SkStream* stream) : SkRefCnt() {
-    if (stream->readU32() != PICTURE_VERSION) {
+    const uint32_t  pictureVersion = stream->readU32();
+    if (pictureVersion != PICTURE_VERSION_ICS &&
+        pictureVersion != PICTURE_VERSION_JB) {
         sk_throw();
     }
 
@@ -203,7 +205,7 @@ SkPicture::SkPicture(SkStream* stream) : SkRefCnt() {
     fPlayback = NULL;
 
     if (stream->readBool()) {
-        fPlayback = SkNEW_ARGS(SkPicturePlayback, (stream));
+        fPlayback = SkNEW_ARGS(SkPicturePlayback, (stream, pictureVersion));
     }
 }
 
@@ -214,7 +216,7 @@ void SkPicture::serialize(SkWStream* stream) const {
         playback = SkNEW_ARGS(SkPicturePlayback, (*fRecord));
     }
 
-    stream->write32(PICTURE_VERSION);
+    stream->write32(PICTURE_VERSION_JB);
     stream->write32(fWidth);
     stream->write32(fHeight);
     if (playback) {
diff --git a/src/core/SkPictureFlat.h b/src/core/SkPictureFlat.h
index 983bfc5..bfd253a 100644
--- a/src/core/SkPictureFlat.h
+++ b/src/core/SkPictureFlat.h
@@ -24,7 +24,6 @@ enum DrawType {
     CONCAT,
     DRAW_BITMAP,
     DRAW_BITMAP_MATRIX,
-    DRAW_BITMAP_NINE,
     DRAW_BITMAP_RECT,
     DRAW_CLEAR,
     DRAW_DATA,
@@ -37,6 +36,7 @@ enum DrawType {
     DRAW_POS_TEXT_H,
     DRAW_POS_TEXT_H_TOP_BOTTOM, // fast variant of DRAW_POS_TEXT_H
     DRAW_RECT,
+    DRAW_SHAPE,
     DRAW_SPRITE,
     DRAW_TEXT,
     DRAW_TEXT_ON_PATH,
@@ -49,7 +49,8 @@ enum DrawType {
     SCALE,
     SET_MATRIX,
     SKEW,
-    TRANSLATE
+    TRANSLATE,
+    DRAW_BITMAP_NINE
 };
 
 enum DrawVertexFlags {
diff --git a/src/core/SkPicturePlayback.cpp b/src/core/SkPicturePlayback.cpp
index c2082c7..f5756a3 100644
--- a/src/core/SkPicturePlayback.cpp
+++ b/src/core/SkPicturePlayback.cpp
@@ -263,6 +263,7 @@ void SkPicturePlayback::dumpSize() const {
 #define PICT_PAINT_TAG      SkSetFourByteTag('p', 'n', 't', ' ')
 #define PICT_PATH_TAG       SkSetFourByteTag('p', 't', 'h', ' ')
 #define PICT_REGION_TAG     SkSetFourByteTag('r', 'g', 'n', ' ')
+#define PICT_SHAPE_TAG      SkSetFourByteTag('s', 'h', 'p', ' ')
 
 #include "SkStream.h"
 
@@ -391,7 +392,7 @@ static int readTagSize(SkStream* stream, uint32_t expectedTag) {
     return stream->readU32();
 }
 
-SkPicturePlayback::SkPicturePlayback(SkStream* stream) {
+SkPicturePlayback::SkPicturePlayback(SkStream* stream, uint32_t pictureVersion) {
     this->init();
 
     int i;
@@ -401,6 +402,7 @@ SkPicturePlayback::SkPicturePlayback(SkStream* stream) {
         void* storage = sk_malloc_throw(size);
         stream->read(storage, size);
         fReader.setMemory(storage, size);
+        fReader.setPictureVersion(pictureVersion);
     }
 
     int factoryCount = readTagSize(stream, PICT_FACTORY_TAG);
@@ -434,6 +436,7 @@ SkPicturePlayback::SkPicturePlayback(SkStream* stream) {
     stream->read(storage.get(), size);
 
     SkFlattenableReadBuffer buffer(storage.get(), size);
+    buffer.setPictureVersion(pictureVersion);
     fFactoryPlayback->setupBuffer(buffer);
     fTFPlayback.setupBuffer(buffer);
 
@@ -467,6 +470,13 @@ SkPicturePlayback::SkPicturePlayback(SkStream* stream) {
         SkDEBUGCODE(uint32_t bytes =) fRegions[i].unflatten(buffer.skip(size));
         SkASSERT(size == bytes);
     }
+
+    if (pictureVersion == PICTURE_VERSION_ICS) {
+        int shapeCount = readTagSize(buffer, PICT_SHAPE_TAG);
+        for (i = 0; i < shapeCount; i++) {
+            buffer.readFlattenable();
+        }
+    }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
diff --git a/src/core/SkPicturePlayback.h b/src/core/SkPicturePlayback.h
index 88f86e2..16ac0b8 100644
--- a/src/core/SkPicturePlayback.h
+++ b/src/core/SkPicturePlayback.h
@@ -32,7 +32,7 @@ public:
     SkPicturePlayback();
     SkPicturePlayback(const SkPicturePlayback& src);
     explicit SkPicturePlayback(const SkPictureRecord& record);
-    explicit SkPicturePlayback(SkStream*);
+    explicit SkPicturePlayback(SkStream*, uint32_t pictureVersion = PICTURE_VERSION_JB);
 
     virtual ~SkPicturePlayback();
 
diff --git a/src/core/SkXfermode.cpp b/src/core/SkXfermode.cpp
index fdf1798..4e1e539 100644
--- a/src/core/SkXfermode.cpp
+++ b/src/core/SkXfermode.cpp
@@ -755,6 +755,12 @@ protected:
             : INHERITED(buffer) {
         fMode = (SkXfermode::Mode)buffer.readU32();
 
+        if (buffer.getPictureVersion() == PICTURE_VERSION_ICS) {
+            fSrcCoeff = (Coeff)buffer.readU32();
+            fDstCoeff = (Coeff)buffer.readU32();
+            return;
+        }
+
         const ProcCoeff& rec = gProcCoeffs[fMode];
         // these may be valid, or may be CANNOT_USE_COEFF
         fSrcCoeff = rec.fSC;
diff --git a/src/effects/SkLayerDrawLooper.cpp b/src/effects/SkLayerDrawLooper.cpp
index acb3e88..16636dc 100644
--- a/src/effects/SkLayerDrawLooper.cpp
+++ b/src/effects/SkLayerDrawLooper.cpp
@@ -218,6 +218,8 @@ SkLayerDrawLooper::SkLayerDrawLooper(SkFlattenableReadBuffer& buffer)
 
     for (int i = 0; i < count; i++) {
         LayerInfo info;
+        if (buffer.getPictureVersion() == PICTURE_VERSION_ICS)
+            info.fFlagsMask = buffer.readInt();
         info.fPaintBits = buffer.readInt();
         info.fColorMode = (SkXfermode::Mode)buffer.readInt();
         info.fOffset.fX = buffer.readScalar();