Fix out-of-memory crashes related to ArrayBuffer allocation

third_party/WebKit/Source/core/dom/DOMArrayBuffer.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef DOMArrayBuffer_h
 #define DOMArrayBuffer_h
 
 #include "core/CoreExport.h"
 #include "core/dom/DOMArrayBufferBase.h"
 #include "wtf/ArrayBuffer.h"
 
 namespace blink {
 
 class CORE_EXPORT DOMArrayBuffer final : public DOMArrayBufferBase {
     DEFINE_WRAPPERTYPEINFO();
 public:
-    static PassRefPtr<DOMArrayBuffer> create(PassRefPtr<WTF::ArrayBuffer> buffer)
+    static PassRefPtr<DOMArrayBuffer> createOrNull(PassRefPtr<WTF::ArrayBuffer> buffer)
     {
+        if (!buffer)
+            return nullptr;
         return adoptRef(new DOMArrayBuffer(buffer));
     }
-    static PassRefPtr<DOMArrayBuffer> create(unsigned numElements, unsigned elementByteSize)
+    static PassRefPtr<DOMArrayBuffer> createOrNull(unsigned numElements, unsigned elementByteSize)
     {
-        return create(WTF::ArrayBuffer::create(numElements, elementByteSize));
+        return createOrNull(WTF::ArrayBuffer::createOrNull(numElements, elementByteSize));
     }
-    static PassRefPtr<DOMArrayBuffer> create(const void* source, unsigned byteLength)
+    static PassRefPtr<DOMArrayBuffer> createOrNull(const void* source, unsigned byteLength)
     {
-        return create(WTF::ArrayBuffer::create(source, byteLength));
+        return createOrNull(WTF::ArrayBuffer::createOrNull(source, byteLength));
+    }
+    static PassRefPtr<DOMArrayBuffer> deprecatedCreateOrCrash(const void* source, unsigned byteLength)
+    {
+        return create(WTF::ArrayBuffer::deprecatedCreateOrCrash(source, byteLength));
+    }
+    static PassRefPtr<DOMArrayBuffer> deprecatedCreateOrCrash(unsigned numElements, unsigned elementByteSize)
+    {
+        return create(WTF::ArrayBuffer::deprecatedCreateOrCrash(numElements, elementByteSize));
     }
     static PassRefPtr<DOMArrayBuffer> create(WTF::ArrayBufferContents& contents)

[binji, 2015/10/16 22:12:39]

it almost feels like these functions that don't allocate should have a different
name. Not sure if that's overkill though

[Justin Novosad, 2015/10/19 16:42:52]

They still construct a DOMArrayBuffer object. So "create" is still appropriate
IMHO. In theory this method can still yield an OOM crash, though very unlikely.

     {
-        return create(WTF::ArrayBuffer::create(contents));
+        return adoptRef(new DOMArrayBuffer(WTF::ArrayBuffer::create(contents)));
+    }
+    static PassRefPtr<DOMArrayBuffer> create(PassRefPtr<WTF::ArrayBuffer> buffer)
+    {
+        ASSERT(buffer);
+        return adoptRef(new DOMArrayBuffer(buffer));
+    }
+    // Only for use by XMLHttpRequest::responseArrayBuffer and
+    // Internals::serializeObject.
+    static PassRefPtr<DOMArrayBuffer> createUninitializedOrNull(unsigned numElements, unsigned elementByteSize)
+    {
+        return createOrNull(WTF::ArrayBuffer::createUninitializedOrNull(numElements, elementByteSize));
     }
 
-    // Only for use by XMLHttpRequest::responseArrayBuffer and
-    // Internals::serializeObject.
-    static PassRefPtr<DOMArrayBuffer> createUninitialized(unsigned numElements, unsigned elementByteSize)
+    PassRefPtr<DOMArrayBuffer> sliceOrNull(int begin, int end) const
     {
-        return create(WTF::ArrayBuffer::createUninitialized(numElements, elementByteSize));
+        return createOrNull(buffer()->sliceOrNull(begin, end));
     }
-
-    PassRefPtr<DOMArrayBuffer> slice(int begin, int end) const
+    PassRefPtr<DOMArrayBuffer> sliceOrNull(int begin) const
     {
-        return create(buffer()->slice(begin, end));
-    }
-    PassRefPtr<DOMArrayBuffer> slice(int begin) const
-    {
-        return create(buffer()->slice(begin));
+        return createOrNull(buffer()->sliceOrNull(begin));
     }
 
     v8::Local<v8::Object> wrap(v8::Isolate*, v8::Local<v8::Object> creationContext) override;
 
 private:
     explicit DOMArrayBuffer(PassRefPtr<WTF::ArrayBuffer> buffer)
         : DOMArrayBufferBase(buffer)
     {
     }
 };
 
 } // namespace blink
 
 #endif // DOMArrayBuffer_h