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-rw-r--r--layout/build/nsLayoutStatics.h71
1 files changed, 71 insertions, 0 deletions
diff --git a/layout/build/nsLayoutStatics.h b/layout/build/nsLayoutStatics.h
new file mode 100644
index 000000000..76663cff5
--- /dev/null
+++ b/layout/build/nsLayoutStatics.h
@@ -0,0 +1,71 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsLayoutStatics_h__
+#define nsLayoutStatics_h__
+
+#include "nscore.h"
+#include "MainThreadUtils.h"
+#include "nsISupportsImpl.h"
+#include "nsDebug.h"
+
+// This isn't really a class, it's a namespace for static methods.
+// Documents and other objects can hold a reference to the layout static
+// objects so that they last past the xpcom-shutdown notification.
+
+class nsLayoutStatics
+{
+public:
+ // Called by the layout module constructor. This call performs an AddRef()
+ // internally.
+ static nsresult Initialize();
+
+ static void AddRef()
+ {
+ NS_ASSERTION(NS_IsMainThread(),
+ "nsLayoutStatics reference counting must be on main thread");
+
+ NS_ASSERTION(sLayoutStaticRefcnt,
+ "nsLayoutStatics already dropped to zero!");
+
+ ++sLayoutStaticRefcnt;
+ NS_LOG_ADDREF(&sLayoutStaticRefcnt, sLayoutStaticRefcnt,
+ "nsLayoutStatics", 1);
+ }
+ static void Release()
+ {
+ NS_ASSERTION(NS_IsMainThread(),
+ "nsLayoutStatics reference counting must be on main thread");
+
+ --sLayoutStaticRefcnt;
+ NS_LOG_RELEASE(&sLayoutStaticRefcnt, sLayoutStaticRefcnt,
+ "nsLayoutStatics");
+
+ if (!sLayoutStaticRefcnt)
+ Shutdown();
+ }
+
+private:
+ // not to be called!
+ nsLayoutStatics();
+
+ static void Shutdown();
+
+ static nsrefcnt sLayoutStaticRefcnt;
+};
+
+class nsLayoutStaticsRef
+{
+public:
+ nsLayoutStaticsRef()
+ {
+ nsLayoutStatics::AddRef();
+ }
+ ~nsLayoutStaticsRef()
+ {
+ nsLayoutStatics::Release();
+ }
+};
+
+#endif // nsLayoutStatics_h__