Minor improvement to path_traits::find_extension()

1 files changed, 5 insertions, 2 deletions

diff --git a/libbutl/path.mxx b/libbutl/path.mxx
index 685e15a..ca034c9 100644
--- a/libbutl/path.mxx
+++ b/libbutl/path.mxx
@@ -317,9 +317,12 @@ LIBBUTL_MODEXPORT namespace butl
     // Return the position of '.' or npos if there is no extension.
     //
     static size_type
-    find_extension (string_type const& s)
+    find_extension (string_type const& s, size_type n = string_type::npos)
     {
-      const C* r (find_extension (s.c_str (), s.size ()));
+      if (n == string_type::npos)
+        n = s.size ();
+
+      const C* r (find_extension (s.c_str (), n));
       return r != nullptr ? r - s.c_str () : string_type::npos;
     }