Added a facility for handling scoped executions.

1 files changed, 73 insertions, 0 deletions

diff --git a/src/scoped_execute.h b/src/scoped_execute.h
new file mode 100644
index 00000000..da3f388e
--- /dev/null
+++ b/src/scoped_execute.h
@@ -0,0 +1,73 @@
+#ifndef _SCOPE_EXECUTE_H
+#define _SCOPE_EXECUTE_H
+
+template <typename T>
+class scoped_variable : public boost::noncopyable
+{
+  T&   var;
+  T    prev;
+  bool enabled;
+
+public:
+  explicit scoped_variable(T& _var)
+    : var(_var), prev(var), enabled(true) {}
+  explicit scoped_variable(T& _var, const T& value)
+    : var(_var), prev(var), enabled(true) {
+    var = value;
+  }
+  ~scoped_variable() {
+    if (enabled)
+      var = prev;
+  }
+
+  void clear() {
+    enabled = false;
+  }
+};
+
+template <typename T>
+class scoped_execute : public boost::noncopyable
+{
+  typedef boost::function<void (T)> function_t;
+
+  function_t code;
+  T	     arg;
+  bool       enabled;
+
+public:
+  explicit scoped_execute(const function_t& _code, T _arg)
+    : code(_code), arg(_arg), enabled(true) {}
+
+  ~scoped_execute() {
+    if (enabled)
+      code(arg);
+  }
+
+  void clear() {
+    enabled = false;
+  }
+};
+
+template <>
+class scoped_execute<void> : public boost::noncopyable
+{
+  typedef boost::function<void ()> function_t;
+
+  function_t code;
+  bool       enabled;
+
+public:
+  explicit scoped_execute(const function_t& _code)
+    : code(_code), enabled(true) {}
+
+  ~scoped_execute() {
+    if (enabled)
+      code();
+  }
+
+  void clear() {
+    enabled = false;
+  }
+};
+
+#endif // _SCOPE_EXECUTE_H