Extract TempSet from llcallbacklist.cpp into its own tempset.h.

1 files changed, 41 insertions, 0 deletions

diff --git a/indra/llcommon/tempset.h b/indra/llcommon/tempset.h
new file mode 100755
index 0000000000..e1496bd5fc
--- /dev/null
+++ b/indra/llcommon/tempset.h
@@ -0,0 +1,41 @@
+/**
+ * @file   tempset.h
+ * @author Nat Goodspeed
+ * @date   2024-06-12
+ * @brief  Temporarily override a variable for scope duration, then restore
+ * 
+ * $LicenseInfo:firstyear=2024&license=viewerlgpl$
+ * Copyright (c) 2024, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_TEMPSET_H)
+#define LL_TEMPSET_H
+
+// RAII class to set specified variable to specified value
+// only for the duration of containing scope
+template <typename VAR, typename VALUE>
+class TempSet
+{
+public:
+    TempSet(VAR& var, const VALUE& value):
+        mVar(var),
+        mOldValue(mVar)
+    {
+        mVar = value;
+    }
+
+    TempSet(const TempSet&) = delete;
+    TempSet& operator=(const TempSet&) = delete;
+
+    ~TempSet()
+    {
+        mVar = mOldValue;
+    }
+
+private:
+    VAR& mVar;
+    VALUE mOldValue;
+};
+
+#endif /* ! defined(LL_TEMPSET_H) */