Sanitize SkMatrixConvolutionImageFilter creation params.

tests/ImageFilterTest.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkBitmapDevice.h"
 #include "SkBitmapSource.h"
@@ skipping 877 matching lines @@
     canvas.drawSprite(bitmap, 0, 0, &paint);
 }
 
 DEF_TEST(HugeBlurImageFilter, reporter) {
     SkBitmap temp;
     temp.allocN32Pixels(100, 100);
     SkBitmapDevice device(temp);
     test_huge_blur(&device, reporter);
 }
 
+DEF_TEST(MatrixConvolutionSanityTest, reporter) {
+    SkScalar kernel[1] = { 0 };
+    SkScalar gain = SK_Scalar1, bias = 0;
+    SkIPoint kernelOffset = SkIPoint::Make(1, 1);
+
+    // Check that an enormous (non-allocatable) kernel gives a NULL filter.
+    SkAutoTUnref<SkImageFilter> conv(SkMatrixConvolutionImageFilter::Create(
+        SkISize::Make(1<<30, 1<<30),
+        kernel,
+        gain,
+        bias,
+        kernelOffset,
+        SkMatrixConvolutionImageFilter::kRepeat_TileMode,
+        false));
+
+    REPORTER_ASSERT(reporter, NULL == conv.get());
+
+    // Check that a NULL kernel gives a NULL filter.
+    conv.reset(SkMatrixConvolutionImageFilter::Create(
+        SkISize::Make(1, 1),
+        NULL,
+        gain,
+        bias,
+        kernelOffset,
+        SkMatrixConvolutionImageFilter::kRepeat_TileMode,
+        false));
+
+    REPORTER_ASSERT(reporter, NULL == conv.get());
+
+    // Check that a kernel width < 1 gives a NULL filter.
+    conv.reset(SkMatrixConvolutionImageFilter::Create(
+        SkISize::Make(0, 1),
+        kernel,
+        gain,
+        bias,
+        kernelOffset,
+        SkMatrixConvolutionImageFilter::kRepeat_TileMode,
+        false));
+
+    REPORTER_ASSERT(reporter, NULL == conv.get());
+
+    // Check that kernel height < 1 gives a NULL filter.
+    conv.reset(SkMatrixConvolutionImageFilter::Create(
+        SkISize::Make(1, -1),
+        kernel,
+        gain,
+        bias,
+        kernelOffset,
+        SkMatrixConvolutionImageFilter::kRepeat_TileMode,
+        false));
+
+    REPORTER_ASSERT(reporter, NULL == conv.get());
+}
+
 static void test_xfermode_cropped_input(SkBaseDevice* device, skiatest::Reporter* reporter) {
     SkCanvas canvas(device);
     canvas.clear(0);
 
     SkBitmap bitmap;
     bitmap.allocN32Pixels(1, 1);
     bitmap.eraseARGB(255, 255, 255, 255);
 
     SkAutoTUnref<SkColorFilter> green(
         SkColorFilter::CreateModeFilter(SK_ColorGREEN, SkXfermode::kSrcIn_Mode));
@@ skipping 123 matching lines @@
 
 DEF_GPUTEST(TestNegativeBlurSigmaGPU, reporter, factory) {
     GrContext* context = factory->get(static_cast<GrContextFactory::GLContextType>(0));
     SkAutoTUnref<SkGpuDevice> device(SkGpuDevice::Create(context,
                                                          SkImageInfo::MakeN32Premul(1, 1),
                                                          gProps,
                                                          0));
     test_negative_blur_sigma(device, reporter);
 }
 #endif