Create unique_ptr for Spot.

* src/misc/unique_ptr.hh: Create unique_ptr for Spot.
* src/misc/Makefile.am: Register this new file.
* src/tgbatest/ltl2tgba.cc: Replace two calls to delete by the
utilisation of unique_ptr.
* src/tgbaalgos/simulation.cc: Replace two calls to delete by the
utilisation of unique_ptr.

src/misc/Makefile.am

@@ -52,6 +52,7 @@ misc_HEADERS = \
   optionmap.hh \
   random.hh \
   timer.hh \
+  unique_ptr.hh \
   version.hh
 
 noinst_LTLIBRARIES = libmisc.la

src/misc/unique_ptr.hh

@@ -0,0 +1,83 @@
+// -*- coding: utf-8 -*-
+// Copyright (C) 2012 Laboratoire de Recherche et
+// Développement de l'Epita (LRDE).
+//
+// This file is part of Spot, a model checking library.
+//
+// Spot 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 2 of the License, or
+// (at your option) any later version.
+//
+// Spot 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 Spot; see the file COPYING.  If not, write to the Free
+// Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+
+#ifndef SPOT_MISC_UNIQUE_PTR_HH
+# define SPOT_MISC_UNIQUE_PTR_HH
+
+namespace spot
+{
+  /// \brief Take ownership of a pointer at its construction, and
+  /// destroy it at the end of the scope.
+  template <typename T>
+  class unique_ptr
+  {
+    typedef T* pointer;
+  public:
+    unique_ptr(pointer ptr)
+      : ptr_(ptr)
+    {
+    }
+
+    ~unique_ptr()
+    {
+      delete ptr_;
+    }
+
+    operator pointer()
+    {
+      return ptr_;
+    }
+
+    pointer
+    operator->()
+    {
+      return ptr_;
+    }
+
+  private:
+    pointer ptr_;
+
+    // This copy gives the ownership of the pointer to the new copy.
+    // Can only be used by make_unique.
+    unique_ptr(const unique_ptr& up)
+    {
+      unique_ptr& non_const_up = const_cast<unique_ptr&>(up);
+      ptr_ = non_const_up.ptr_;
+      non_const_up.ptr_ = 0;
+    }
+
+    // Allow `make_unique' to have an access to the private copy.
+    template <typename V> friend unique_ptr<V> make_unique(V* ptr);
+
+    unique_ptr& operator=(const unique_ptr&);
+  };
+
+
+  /// \brief Change a pointer into a unique_ptr.
+  template <typename T>
+  inline unique_ptr<T> make_unique(T* ptr)
+  {
+    return unique_ptr<T>(ptr);
+  }
+}
+
+
+#endif // !SPOT_MISC_UNIQUE_PTR_HH