Initial error handling code

src/effects/SkMatrixConvolutionImageFilter.cpp

 /*
  * Copyright 2012 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkMatrixConvolutionImageFilter.h"
 #include "SkBitmap.h"
 #include "SkColorPriv.h"
 #include "SkFlattenableBuffers.h"
 #include "SkRect.h"
 #include "SkUnPreMultiply.h"
 
 #if SK_SUPPORT_GPU
 #include "gl/GrGLEffect.h"
 #include "effects/GrSingleTextureEffect.h"
 #include "GrTBackendEffectFactory.h"
 #include "GrTexture.h"
 #include "SkMatrix.h"
 #endif
 
+static bool tile_mode_is_valid(SkMatrixConvolutionImageFilter::TileMode tileMode) {
+    switch (tileMode) {
+    case SkMatrixConvolutionImageFilter::kClamp_TileMode:
+    case SkMatrixConvolutionImageFilter::kRepeat_TileMode:
+    case SkMatrixConvolutionImageFilter::kClampToBlack_TileMode:
+        return true;
+    default:
+        break;
+    }
+    return false;
+}
+
 SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(
     const SkISize& kernelSize,
     const SkScalar* kernel,
     SkScalar gain,
     SkScalar bias,
     const SkIPoint& target,
     TileMode tileMode,
     bool convolveAlpha,
     SkImageFilter* input,
     const CropRect* cropRect)
@@ skipping 19 matching lines @@
     uint32_t size = fKernelSize.fWidth * fKernelSize.fHeight;
     fKernel = SkNEW_ARRAY(SkScalar, size);
     SkDEBUGCODE(uint32_t readSize = )buffer.readScalarArray(fKernel);
     SkASSERT(readSize == size);
     fGain = buffer.readScalar();
     fBias = buffer.readScalar();
     fTarget.fX = buffer.readInt();
     fTarget.fY = buffer.readInt();
     fTileMode = (TileMode) buffer.readInt();
     fConvolveAlpha = buffer.readBool();
+    buffer.validate(SkScalarIsFinite(fGain) &&
+                    SkScalarIsFinite(fBias) &&
+                    tile_mode_is_valid(fTileMode));
 }
 
 void SkMatrixConvolutionImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeInt(fKernelSize.fWidth);
     buffer.writeInt(fKernelSize.fHeight);
     buffer.writeScalarArray(fKernel, fKernelSize.fWidth * fKernelSize.fHeight);
     buffer.writeScalar(fGain);
     buffer.writeScalar(fBias);
     buffer.writeInt(fTarget.fX);
@@ skipping 558 matching lines @@
                                                 fBias,
                                                 fTarget,
                                                 fTileMode,
                                                 fConvolveAlpha);
     return true;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #endif