enhance: Add util::BitSet

1 files changed, 121 insertions, 0 deletions

diff --git a/src/util/BitSet.hpp b/src/util/BitSet.hpp
new file mode 100644
index 00000000..9cf146dc
--- /dev/null
+++ b/src/util/BitSet.hpp
@@ -0,0 +1,121 @@
+// Copyright (C) 2023 Joel Rosdahl and other contributors
+//
+// See doc/AUTHORS.adoc for a complete list of contributors.
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3 of the License, or (at your option)
+// any later version.
+//
+// This program is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+// more details.
+//
+// You should have received a copy of the GNU General Public License along with
+// this program; if not, write to the Free Software Foundation, Inc., 51
+// Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+#pragma once
+
+#include <type_traits>
+
+namespace util {
+
+template<typename T> class BitSet
+{
+public:
+  explicit BitSet(T value = {});
+  BitSet(const BitSet& set);
+
+  BitSet& operator=(const BitSet& set);
+
+  bool contains(T value) const;
+  bool empty() const;
+
+  void clear();
+  void insert(T value);
+  void insert(const BitSet& set);
+  void erase(T value);
+
+  template<typename U> static BitSet<T> from_bitmask(U mask);
+  typename std::underlying_type<T>::type to_bitmask() const;
+
+private:
+  typename std::underlying_type<T>::type m_value;
+};
+
+// --- Inline implementations ---
+
+template<typename T>
+inline BitSet<T>::BitSet(T value)
+  : m_value(static_cast<typename std::underlying_type<T>::type>(value))
+{
+}
+
+template<typename T>
+inline BitSet<T>::BitSet(const BitSet& set) : m_value(set.m_value)
+{
+}
+
+template<typename T>
+inline BitSet<T>&
+BitSet<T>::operator=(const BitSet& set)
+{
+  m_value = set.m_value;
+  return *this;
+}
+
+template<typename T>
+inline bool
+BitSet<T>::contains(T value) const
+{
+  return m_value & static_cast<typename std::underlying_type<T>::type>(value);
+}
+
+template<typename T>
+inline bool
+BitSet<T>::empty() const
+{
+  return to_bitmask() == 0;
+}
+
+template<typename T>
+inline void
+BitSet<T>::insert(T value)
+{
+  m_value |= static_cast<typename std::underlying_type<T>::type>(value);
+}
+
+template<typename T>
+inline void
+BitSet<T>::insert(const BitSet& set)
+{
+  m_value |= static_cast<typename std::underlying_type<T>::type>(set.m_value);
+}
+
+template<typename T>
+inline void
+BitSet<T>::erase(T value)
+{
+  m_value &= ~static_cast<typename std::underlying_type<T>::type>(value);
+}
+
+template<typename T>
+template<typename U>
+inline BitSet<T>
+BitSet<T>::from_bitmask(U mask)
+{
+  BitSet result;
+  result.m_value = mask;
+  return result;
+}
+
+template<typename T>
+inline typename std::underlying_type<T>::type
+BitSet<T>::to_bitmask() const
+{
+  return m_value;
+}
+
+} // namespace util