Reorganizing source code. Created util dir

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/util/scoped_numeral_buffer.h

@@ -0,0 +1,68 @@
+/*++
+Copyright (c) 2012 Microsoft Corporation
+
+Module Name:
+
+    scoped_numeral_buffer.h
+
+Abstract:
+
+    Wrapper for easying the pain when using buffers of numerals.
+
+Author:
+
+    Leonardo de Moura (leonardo) 2012-01-23
+
+Revision History:
+
+--*/
+#ifndef _SCOPED_NUMERAL_BUFFER_H_
+#define _SCOPED_NUMERAL_BUFFER_H_
+
+#include"buffer.h"
+
+template<typename Manager, unsigned INITIAL_SIZE = 16>
+class _scoped_numeral_buffer : public sbuffer<typename Manager::numeral, INITIAL_SIZE> {
+    typedef sbuffer<typename Manager::numeral, INITIAL_SIZE> super;
+    Manager & m_manager;
+    _scoped_numeral_buffer(_scoped_numeral_buffer const & v);
+public:
+    _scoped_numeral_buffer(Manager & m):m_manager(m) {}
+    ~_scoped_numeral_buffer() {
+        reset();
+    }
+
+    void reset() {
+        unsigned sz = this->size();
+        for (unsigned i = 0; i < sz; i++) {
+            m().del(this->operator[](i));
+        }
+        super::reset();
+    }
+
+    Manager & m() const { return m_manager; }
+
+    void push_back(typename Manager::numeral const & v) {
+        super::push_back(typename Manager::numeral());
+        m_manager.set(this->back(), v);
+    }
+
+    void shrink(unsigned sz) {
+        unsigned old_sz = this->size();
+        if (old_sz == sz)
+            return;
+        for (unsigned i = sz; i < old_sz; i++)
+            m().del(this->operator[](i));
+        super::shrink(sz);
+    }
+
+    void resize(unsigned sz) {
+        unsigned old_sz = this->size();
+        if (sz <= old_sz)
+            shrink(sz);
+        typename Manager::numeral zero(0);
+        super::resize(sz, zero);
+    }
+};
+
+#endif