Initial revision

From-SVN: r22179

libstdc++/stl/char_traits.h

+/*
+ * Copyright (c) 1997
+ * Silicon Graphics Computer Systems, Inc.
+ *
+ * Permission to use, copy, modify, distribute and sell this software
+ * and its documentation for any purpose is hereby granted without fee,
+ * provided that the above copyright notice appear in all copies and
+ * that both that copyright notice and this permission notice appear
+ * in supporting documentation.  Silicon Graphics makes no
+ * representations about the suitability of this software for any
+ * purpose.  It is provided "as is" without express or implied warranty.
+ */ 
+
+#ifndef __SGI_STL_CHAR_TRAITS_H
+#define __SGI_STL_CHAR_TRAITS_H
+
+#include <string.h>
+#include <wchar.h>
+
+__STL_BEGIN_NAMESPACE
+
+// Class __char_traits_base.
+
+template <class _CharT, class _IntT> struct __char_traits_base {
+  typedef _CharT char_type;
+  typedef _IntT int_type;
+  // typedef streamoff off_type;
+  // typedef streampos pos_type;
+  // typedef mbstate_t state_type;
+
+  static void assign(char_type& __c1, const char_type& __c2) { __c1 = __c2; }
+  static bool eq(const _CharT& __c1, const _CharT& __c2) 
+    { return __c1 == __c2; }
+  static bool lt(const _CharT& __c1, const _CharT& __c2) 
+    { return __c1 < __c2; }
+
+  static int compare(const _CharT* __s1, const _CharT* __s2, size_t __n) {
+    for (size_t __i = 0; __i < __n; ++__i)
+      if (!eq(__s1[__i], __s2[__i]))
+        return __s1[__i] < __s2[__i] ? -1 : 1;
+    return 0;
+  }
+
+  static size_t length(const _CharT* __s) {
+    const _CharT __null = _CharT();
+    size_t __i;
+    for (__i = 0; !eq(__s[__i], __null); ++__i)
+      {}
+    return __i;
+  }
+
+  static const _CharT* find(const _CharT* __s, size_t __n, const _CharT& __c)
+  {
+    for ( ; __n > 0 ; ++__s, --__n)
+      if (eq(*__s, __c))
+        return __s;
+    return 0;
+  }
+
+  static _CharT* move(_CharT* __s1, const _CharT* __s2, size_t __n) {
+    memmove(__s1, __s2, __n * sizeof(_CharT));
+    return __s1;
+  }
+    
+  static _CharT* copy(_CharT* __s1, const _CharT* __s2, size_t __n) {
+    memcpy(__s1, __s2, __n * sizeof(_CharT));
+    return __s1;
+  } 
+
+  static _CharT* assign(_CharT* __s, size_t __n, _CharT __c) {
+    for (size_t __i = 0; __i < __n; ++__i)
+      __s[__i] = __c;
+    return __s;
+  }
+
+  static int_type not_eof(const int_type& __c) {
+    return !eq(__c, eof()) ? __c : 0;
+  }
+
+  static char_type to_char_type(const int_type& __c) {
+    return static_cast<char_type>(__c);
+  }
+
+  static int_type to_int_type(const char_type& __c) {
+    return static_cast<int_type>(__c);
+  }
+
+  static bool eq_int_type(const int_type& __c1, const int_type& __c2) {
+    return __c1 == __c2;
+  }
+
+  static int_type eof() {
+    return static_cast<int_type>(-1);
+  }
+};
+
+// Generic char_traits class.  Note that this class is provided only
+//  as a base for explicit specialization; it is unlikely to be useful
+//  as is for any particular user-defined type.  In particular, it 
+//  *will not work* for a non-POD type.
+
+template <class _CharT> struct char_traits
+  : public __char_traits_base<_CharT, _CharT>
+{};
+
+// Specialization for char.
+
+template<> struct char_traits<char> 
+  : public __char_traits_base<char, int>
+{
+  static int compare(const char* __s1, const char* __s2, size_t __n) 
+    { return memcmp(__s1, __s2, __n); }
+  
+  static size_t length(const char* __s) { return strlen(__s); }
+
+  static void assign(char& __c1, const char& __c2) { __c1 = __c2; }
+
+  static char* assign(char* __s, size_t __n, char __c)
+    { memset(__s, __c, __n); return __s; }
+};
+
+// Specialization for wchar_t.
+
+template<> struct char_traits<wchar_t>
+  : public __char_traits_base<wchar_t, wint_t>
+{};
+
+__STL_END_NAMESPACE
+
+#endif /* __SGI_STL_CHAR_TRAITS_H */
+
+// Local Variables:
+// mode:C++
+// End:
+