Initial error handling code

src/effects/SkMagnifierImageFilter.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 "SkBitmap.h"
 #include "SkMagnifierImageFilter.h"
 #include "SkColorPriv.h"
@@ skipping 234 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 SkMagnifierImageFilter::SkMagnifierImageFilter(SkFlattenableReadBuffer& buffer)
   : INHERITED(buffer) {
     float x = buffer.readScalar();
     float y = buffer.readScalar();
     float width = buffer.readScalar();
     float height = buffer.readScalar();
     fSrcRect = SkRect::MakeXYWH(x, y, width, height);
     fInset = buffer.readScalar();
+
+    buffer.validateData(fSrcRect.isValid() && SkScalarIsFinite(fInset));
 }
 
 // FIXME:  implement single-input semantics
 SkMagnifierImageFilter::SkMagnifierImageFilter(SkRect srcRect, SkScalar inset)
     : INHERITED(0), fSrcRect(srcRect), fInset(inset) {
     SkASSERT(srcRect.x() >= 0 && srcRect.y() >= 0 && inset >= 0);
 }
 
 #if SK_SUPPORT_GPU
 bool SkMagnifierImageFilter::asNewEffect(GrEffectRef** effect, GrTexture* texture, const SkMatrix&) const {
@@ skipping 77 matching lines @@
 
             int x_val = SkMin32(SkScalarFloorToInt(x_interp), width - 1);
             int y_val = SkMin32(SkScalarFloorToInt(y_interp), height - 1);
 
             *dptr = sptr[y_val * width + x_val];
             dptr++;
         }
     }
     return true;
 }