Implement Blob.close().

Source/core/fileapi/Blob.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/fileapi/Blob.h"
 
+#include "core/dom/ExecutionContext.h"
+#include "core/html/PublicURLManager.h"
 #include "platform/blob/BlobRegistry.h"
 #include "platform/blob/BlobURL.h"
 
 namespace WebCore {
 
 namespace {
 
 class BlobURLRegistry FINAL : public URLRegistry {
 public:
     virtual void registerURL(SecurityOrigin*, const KURL&, URLRegistrable*) OVERRIDE;
     virtual void unregisterURL(const KURL&) OVERRIDE;
 
     static URLRegistry& registry();
 };
 
-void BlobURLRegistry::registerURL(SecurityOrigin* origin, const KURL& publicURL, URLRegistrable* blob)
+void BlobURLRegistry::registerURL(SecurityOrigin* origin, const KURL& publicURL, URLRegistrable* registrableObject)
 {
-    ASSERT(&blob->registry() == this);
-    BlobRegistry::registerPublicBlobURL(origin, publicURL, static_cast<Blob*>(blob)->blobDataHandle());
+    ASSERT(&registrableObject->registry() == this);
+    Blob* blob = static_cast<Blob*>(registrableObject);
+    BlobRegistry::registerPublicBlobURL(origin, publicURL, blob->blobDataHandle());
 }
 
 void BlobURLRegistry::unregisterURL(const KURL& publicURL)
 {
     BlobRegistry::revokePublicBlobURL(publicURL);
 }
 
 URLRegistry& BlobURLRegistry::registry()
 {
     DEFINE_STATIC_LOCAL(BlobURLRegistry, instance, ());
     return instance;
 }
 
 } // namespace
 
 Blob::Blob(PassRefPtr<BlobDataHandle> dataHandle)
     : m_blobDataHandle(dataHandle)
+    , m_hasBeenClosed(false)
 {
     ScriptWrappable::init(this);
 }
 
 Blob::~Blob()
 {
 }
 
 void Blob::clampSliceOffsets(long long size, long long& start, long long& end)
 {
@@ skipping 24 matching lines @@
     long long size = this->size();
     clampSliceOffsets(size, start, end);
 
     long long length = end - start;
     OwnPtr<BlobData> blobData = BlobData::create();
     blobData->setContentType(contentType);
     blobData->appendBlob(m_blobDataHandle, start, length);
     return Blob::create(BlobDataHandle::create(blobData.release(), length));
 }
 
+void Blob::close(ExecutionContext* executionContext)
+{
+    if (!hasBeenClosed()) {
+        // Dereferencing a Blob that has been closed should result in
+        // a network error. Revoke URLs registered against it through
+        // its UUID.
+        executionContext->publicURLManager().revoke(uuid());
+
+        // A closed Blob should have size zero, which most consumers
+        // will treat as an empty Blob. The exception being the FileReader
+        // read operations which will throw.
+        OwnPtr<BlobData> blobData = BlobData::create();
+        blobData->setContentType(type());
+        m_blobDataHandle = BlobDataHandle::create(blobData.release(), 0);

[michaeln, 2014/02/12 20:33:04]

nice and safe :)

+        m_hasBeenClosed = true;
+    }
+}
+
 void Blob::appendTo(BlobData& blobData) const
 {
     blobData.appendBlob(m_blobDataHandle, 0, m_blobDataHandle->size());
 }
 
 URLRegistry& Blob::registry() const
 {
     return BlobURLRegistry::registry();
 }
 
-
 } // namespace WebCore