add experimental tls (for font cache eventually)

git-svn-id: http://skia.googlecode.com/svn/trunk@3748 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 36 insertions, 0 deletions

diff --git a/src/core/SkTLS.h b/src/core/SkTLS.h
new file mode 100644
index 0000000000..86886f0080
--- /dev/null
+++ b/src/core/SkTLS.h
@@ -0,0 +1,36 @@
+//
+//  SkTLS.h
+//  
+//
+//  Created by Mike Reed on 4/21/12.
+//  Copyright (c) 2012 __MyCompanyName__. All rights reserved.
+//
+
+#ifndef SkTLS_DEFINED
+#define SkTLS_DEFINED
+
+#include "SkTypes.h"
+
+class SkTLS {
+public:
+    typedef void* (*CreateProc)();
+    typedef void  (*DeleteProc)(void*);
+
+    /**
+     *  Create proc is called once per thread, and its return value is cached
+     *  and returned by this call, treating the proc as a key. When this thread
+     *  exists, if DeleteProc is not NULL, it is called and passed the value
+     *  that was returned by CreateProc.
+     */
+    static void* Get(CreateProc, DeleteProc);
+
+    /**
+     *  If Get() has previously been called with this CreateProc, then this
+     *  returns its cached data, otherwise it returns NULL. The CreateProc is
+     *  never invoked in Find, it is only used as a key for searching the
+     *  cache.
+     */
+    static void* Find(CreateProc);
+};
+
+#endif