Adding error checks to SkRBuffer

tests/SerializationTest.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 "SkOrderedWriteBuffer.h"
 #include "SkValidatingReadBuffer.h"
 #include "Test.h"
@@ skipping 91 matching lines @@
     writer.setFlags(SkOrderedWriteBuffer::kValidation_Flag);
     SerializationUtils<T>::Write(writer, testObj);
     size_t bytesWritten = writer.bytesWritten();
     REPORTER_ASSERT(reporter, SkAlign4(bytesWritten) == bytesWritten);
 
     unsigned char dataWritten[1024];
     writer.writeToMemory(dataWritten);
 
     // Make sure this fails when it should (test with smaller size, but still multiple of 4)
     SkValidatingReadBuffer buffer(dataWritten, bytesWritten - 4);
-    const unsigned char* peekBefore = static_cast<const unsigned char*>(buffer.skip(0));
-    SerializationUtils<T>::Read(buffer, testObj);
-    const unsigned char* peekAfter = static_cast<const unsigned char*>(buffer.skip(0));
-    // This should have failed, since the buffer is too small to read a matrix from it
-    REPORTER_ASSERT(reporter, peekBefore == peekAfter);
+    T obj;
+    SerializationUtils<T>::Read(buffer, &obj);
+    REPORTER_ASSERT(reporter, !buffer.validate(true));
 
     // Make sure this succeeds when it should
     SkValidatingReadBuffer buffer2(dataWritten, bytesWritten);
-    peekBefore = static_cast<const unsigned char*>(buffer2.skip(0));
-    SerializationUtils<T>::Read(buffer2, testObj);
-    peekAfter = static_cast<const unsigned char*>(buffer2.skip(0));
+    const unsigned char* peekBefore = static_cast<const unsigned char*>(buffer2.skip(0));
+    T obj2;
+    SerializationUtils<T>::Read(buffer2, &obj2);
+    const unsigned char* peekAfter = static_cast<const unsigned char*>(buffer2.skip(0));
     // This should have succeeded, since there are enough bytes to read this
+    REPORTER_ASSERT(reporter, buffer2.validate(true));
     REPORTER_ASSERT(reporter, static_cast<size_t>(peekAfter - peekBefore) == bytesWritten);
 
     TestAlignment(testObj, reporter);
 }
 
 template<typename T>
 static void TestArraySerialization(T* data, skiatest::Reporter* reporter) {
     SkOrderedWriteBuffer writer(1024);
     writer.setFlags(SkOrderedWriteBuffer::kValidation_Flag);
     SerializationUtils<T>::Write(writer, data, kArraySize);
@@ skipping 69 matching lines @@
 
     // Test readScalarArray
     {
         SkScalar data[kArraySize];
         TestArraySerialization(data, reporter);
     }
 }
 
 #include "TestClassDef.h"
 DEFINE_TESTCLASS("Serialization", SerializationClass, Tests)