Initial import of the Chrome Frame codebase. Integration in chrome.gyp coming...

chrome_frame/ns_isupports_impl.h

+// Copyright (c) 2009 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 CHROME_FRAME_NS_ISUPPORTS_IMPL_H_
+#define CHROME_FRAME_NS_ISUPPORTS_IMPL_H_
+
+#include "base/basictypes.h"
+#include "base/logging.h"
+#include "base/platform_thread.h"
+#include "chrome_frame/utils.h"
+#include "third_party/xulrunner-sdk/win/include/xpcom/nscore.h"
+#include "third_party/xulrunner-sdk/win/include/xpcom/nsid.h"
+#include "third_party/xulrunner-sdk/win/include/xpcom/nsISupportsBase.h"
+
+// A simple single-threaded implementation of methods needed to support
+// nsISupports. Must be inherited by classes that also inherit from nsISupports.
+template<class Derived>
+class NsISupportsImplBase {
+ public:
+  NsISupportsImplBase() : nsiimpl_ref_count_(0) {
+    nsiimpl_thread_id_ = PlatformThread::CurrentId();
+  }
+
+  virtual ~NsISupportsImplBase() {
+    DCHECK(nsiimpl_thread_id_ == PlatformThread::CurrentId());
+  }
+
+  NS_IMETHOD QueryInterface(REFNSIID iid, void** ptr) {
+    DCHECK(nsiimpl_thread_id_ == PlatformThread::CurrentId());
+    nsresult res = NS_NOINTERFACE;
+
+    if (memcmp(&iid, &__uuidof(nsISupports), sizeof(nsIID)) == 0) {
+      *ptr = static_cast<nsISupports*>(static_cast<typename Derived*>(this));
+      AddRef();
+      res = NS_OK;
+    }
+
+    return res;
+  }
+
+  NS_IMETHOD_(nsrefcnt) AddRef() {
+    DCHECK(nsiimpl_thread_id_ == PlatformThread::CurrentId());
+    nsiimpl_ref_count_++;
+    return nsiimpl_ref_count_;
+  }
+
+  NS_IMETHOD_(nsrefcnt) Release() {
+    DCHECK(nsiimpl_thread_id_ == PlatformThread::CurrentId());
+    nsiimpl_ref_count_--;
+
+    if (!nsiimpl_ref_count_) {
+      Derived* me = static_cast<Derived*>(this);
+      delete me;
+      return 0;
+    }
+
+    return nsiimpl_ref_count_;
+  }
+
+ protected:
+  nsrefcnt nsiimpl_ref_count_;
+  AddRefModule nsiimpl_module_ref_;
+  // used to DCHECK on expected single-threaded usage
+  uint64 nsiimpl_thread_id_;
+};
+
+#endif  // CHROME_FRAME_NS_ISUPPORTS_IMPL_H_