1 files changed, 54 insertions, 0 deletions
diff --git a/src/mongo/db/globals.h b/src/mongo/db/globals.h
new file mode 100644
index 00000000000..093bec76a0e
--- /dev/null
+++ b/src/mongo/db/globals.h
@@ -0,0 +1,54 @@
+// @file globals.h
+// grouping of global variables to make concurrency work clearer
+
+#pragma once
+
+namespace mongo {
+
+    void assertStartingUp();
+
+    // this is prototype for now, we'll see if it is helpful
+
+    /** "value is Const After Server Init" helper
+    *
+    * Example:
+    *
+    *  casi<int> foo = 3;
+    *  foo.ref() = 4; // asserts if not still in server init
+    *  int x = foo+1; // ok anytime
+    *
+    */
+    template< class T >
+    class casi : boost::noncopyable {
+        T val;
+    public:
+        casi(const T& t) : val(t) { 
+            DEV assertStartingUp();
+        }
+        operator const T& () { return val; }
+        T& ref() { 
+            DEV assertStartingUp();
+            return val; 
+        }
+    };
+
+    /** partially specialized for cases where out global variable is a pointer -- we want the value
+     * pointed at to be constant, not just the pointer itself
+     */
+    template< typename T >
+    class casi<T*> : boost::noncopyable {
+        T * val;
+        void operator=(T*);
+    public:
+        casi(T* t) : val(t) { 
+            DEV assertStartingUp();
+        }
+        operator const T* () { return val; }
+        const T* get() { return val; }
+        T*& ref() { 
+            DEV assertStartingUp();
+            return val; 
+        }
+    };
+
+}