[webcrypto] Fix TODO regarding asynchronous completion of crypto operations.

Source/modules/crypto/CryptoResultImpl.cpp

 /*
  * Copyright (C) 2013 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 14 matching lines @@
  * 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 "modules/crypto/CryptoResultImpl.h"
 
 #include "bindings/v8/ScriptPromiseResolver.h"
+#include "bindings/v8/ScriptScope.h"
+#include "bindings/v8/ScriptState.h"
+#include "core/dom/ExecutionContext.h"
 #include "modules/crypto/Key.h"
 #include "modules/crypto/KeyPair.h"
 #include "modules/crypto/NormalizeAlgorithm.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebArrayBuffer.h"
 #include "public/platform/WebCryptoAlgorithm.h"
 #include "wtf/ArrayBufferView.h"
 
 namespace WebCore {
 
 CryptoResultImpl::~CryptoResultImpl()
 {
     ASSERT(m_finished);
 }
 
 PassRefPtr<CryptoResultImpl> CryptoResultImpl::create(ScriptPromise promise)
 {
-    return adoptRef(new CryptoResultImpl(promise));
+    return adoptRef(new CryptoResultImpl(activeExecutionContext(), DOMWrapperWorld::current(), promise));
 }
 
 void CryptoResultImpl::completeWithError()
 {
+    CheckValidThread();
+
+    if (!canCompletePromise())
+        return;
+
+    // Set up V8
+    v8::HandleScope handleScope(toIsolate(executionContext()));
+    v8::Handle<v8::Context> v8Context = toV8Context(executionContext(), m_world.get());
+    if (v8Context.IsEmpty())
+        return;
+    v8::Context::Scope scope(v8Context);

[abarth-chromium, 2014/01/16 04:41:08]

Maybe DOMRequestState would be helpful here?

https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...

Feel free to generalize it for your use case.

[eroman, 2014/01/16 20:24:16]

Perfect, just what I needed!

Updated, PTAL.

+
     m_promiseResolver->reject(ScriptValue::createNull());
     finish();
 }
 
 void CryptoResultImpl::completeWithBuffer(const blink::WebArrayBuffer& buffer)
 {
+    CheckValidThread();
+
+    if (!canCompletePromise())
+        return;
+
+    // Set up V8
+    v8::HandleScope handleScope(toIsolate(executionContext()));
+    v8::Handle<v8::Context> v8Context = toV8Context(executionContext(), m_world.get());
+    if (v8Context.IsEmpty())
+        return;
+    v8::Context::Scope scope(v8Context);
+
     m_promiseResolver->resolve(PassRefPtr<ArrayBuffer>(buffer));
     finish();
 }
 
 void CryptoResultImpl::completeWithBoolean(bool b)
 {
+    CheckValidThread();
+
+    if (!canCompletePromise())
+        return;
+
+    // Set up V8
+    v8::HandleScope handleScope(toIsolate(executionContext()));
+    v8::Handle<v8::Context> v8Context = toV8Context(executionContext(), m_world.get());
+    if (v8Context.IsEmpty())
+        return;
+    v8::Context::Scope scope(v8Context);
+
     m_promiseResolver->resolve(ScriptValue::createBoolean(b));
     finish();
 }
 
 void CryptoResultImpl::completeWithKey(const blink::WebCryptoKey& key)
 {
+    CheckValidThread();
+
+    if (!canCompletePromise())
+        return;
+
+    // Set up V8
+    v8::HandleScope handleScope(toIsolate(executionContext()));
+    v8::Handle<v8::Context> v8Context = toV8Context(executionContext(), m_world.get());
+    if (v8Context.IsEmpty())
+        return;
+    v8::Context::Scope scope(v8Context);
+
     m_promiseResolver->resolve(Key::create(key));
     finish();
 }
 
 void CryptoResultImpl::completeWithKeyPair(const blink::WebCryptoKey& publicKey, const blink::WebCryptoKey& privateKey)
 {
+    CheckValidThread();
+
+    if (!canCompletePromise())
+        return;
+
+    // Set up V8
+    v8::HandleScope handleScope(toIsolate(executionContext()));
+    v8::Handle<v8::Context> v8Context = toV8Context(executionContext(), m_world.get());
+    if (v8Context.IsEmpty())
+        return;
+    v8::Context::Scope scope(v8Context);
+
     m_promiseResolver->resolve(KeyPair::create(publicKey, privateKey));
+
     finish();
 }
 
-CryptoResultImpl::CryptoResultImpl(ScriptPromise promise)
-    : m_promiseResolver(ScriptPromiseResolver::create(promise))
-    , m_finished(false) { }
+CryptoResultImpl::CryptoResultImpl(ExecutionContext* context, DOMWrapperWorld* world, ScriptPromise promise)
+    : ContextLifecycleObserver(context)
+    , m_promiseResolver(ScriptPromiseResolver::create(promise))
+    , m_world(world)
+#if !ASSERT_DISABLED
+    , m_owningThread(currentThread())
+    , m_finished(false)
+#endif
+{
+    ASSERT(toIsolate(context) == promise.isolate());
+}
 
 void CryptoResultImpl::finish()
 {
     ASSERT(!m_finished);
+#if !ASSERT_DISABLED
     m_finished = true;
+#endif
+    m_promiseResolver.clear();
+    m_world.clear();
+}
+
+void CryptoResultImpl::CheckValidThread() const
+{
+    ASSERT(m_owningThread == currentThread());
+}
+
+void CryptoResultImpl::contextDestroyed()
+{
+    ContextLifecycleObserver::contextDestroyed();
+
+    // Abandon the promise without completing it when the context goes away.
+    // The CryptoResultImpl will live on until the operation is completed by
+    // the embedder (currently not cancellable). Once it does complete
+    // canCompletePromise() will be false.
+    m_promiseResolver.clear();
+    m_world.clear();
+
+    ASSERT(!canCompletePromise());
+}
+
+bool CryptoResultImpl::canCompletePromise() const
+{
+    ExecutionContext* context = executionContext();
+    return context && !context->activeDOMObjectsAreSuspended() && !context->activeDOMObjectsAreStopped();
 }
 
 } // namespace WebCore