libcxx/test/support/constexpr_char_traits.h

   1 // -*- C++ -*-
   2 //===-------------------- constexpr_char_traits ---------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef _CONSTEXPR_CHAR_TRAITS
  11 #define _CONSTEXPR_CHAR_TRAITS
  12
  13 #include <string>
  14 #include <cassert>
  15
  16 #include "test_macros.h"
  17
  18 template <class _CharT>
  19 struct constexpr_char_traits
  20 {
  21     typedef _CharT    char_type;
  22     typedef int       int_type;
  23     typedef std::streamoff off_type;
  24     typedef std::streampos pos_type;
  25     typedef std::mbstate_t state_type;
  26
  27     static TEST_CONSTEXPR_CXX14 void assign(char_type& __c1, const char_type& __c2) TEST_NOEXCEPT
  28         {__c1 = __c2;}
  29
  30     static TEST_CONSTEXPR bool eq(char_type __c1, char_type __c2) TEST_NOEXCEPT
  31         {return __c1 == __c2;}
  32
  33     static TEST_CONSTEXPR  bool lt(char_type __c1, char_type __c2) TEST_NOEXCEPT
  34         {return __c1 < __c2;}
  35
  36     static TEST_CONSTEXPR_CXX14 int              compare(const char_type* __s1, const char_type* __s2, size_t __n);
  37     static TEST_CONSTEXPR_CXX14 size_t           length(const char_type* __s);
  38     static TEST_CONSTEXPR_CXX14 const char_type* find(const char_type* __s, size_t __n, const char_type& __a);
  39     static TEST_CONSTEXPR_CXX14 char_type*       move(char_type* __s1, const char_type* __s2, size_t __n);
  40     static TEST_CONSTEXPR_CXX14 char_type*       copy(char_type* __s1, const char_type* __s2, size_t __n);
  41     static TEST_CONSTEXPR_CXX14 char_type*       assign(char_type* __s, size_t __n, char_type __a);
  42
  43     static TEST_CONSTEXPR int_type  not_eof(int_type __c) TEST_NOEXCEPT
  44         {return eq_int_type(__c, eof()) ? ~eof() : __c;}
  45
  46     static TEST_CONSTEXPR char_type to_char_type(int_type __c) TEST_NOEXCEPT
  47         {return char_type(__c);}
  48
  49     static TEST_CONSTEXPR int_type  to_int_type(char_type __c) TEST_NOEXCEPT
  50         {return int_type(__c);}
  51
  52     static TEST_CONSTEXPR bool      eq_int_type(int_type __c1, int_type __c2) TEST_NOEXCEPT
  53         {return __c1 == __c2;}
  54
  55     static TEST_CONSTEXPR int_type  eof() TEST_NOEXCEPT
  56         {return int_type(EOF);}
  57 };
  58
  59
  60 template <class _CharT>
  61 TEST_CONSTEXPR_CXX14 int
  62 constexpr_char_traits<_CharT>::compare(const char_type* __s1, const char_type* __s2, size_t __n)
  63 {
  64     for (; __n; --__n, ++__s1, ++__s2)
  65     {
  66         if (lt(*__s1, *__s2))
  67             return -1;
  68         if (lt(*__s2, *__s1))
  69             return 1;
  70     }
  71     return 0;
  72 }
  73
  74 template <class _CharT>
  75 TEST_CONSTEXPR_CXX14 size_t
  76 constexpr_char_traits<_CharT>::length(const char_type* __s)
  77 {
  78     size_t __len = 0;
  79     for (; !eq(*__s, char_type(0)); ++__s)
  80         ++__len;
  81     return __len;
  82 }
  83
  84 template <class _CharT>
  85 TEST_CONSTEXPR_CXX14 const _CharT*
  86 constexpr_char_traits<_CharT>::find(const char_type* __s, size_t __n, const char_type& __a)
  87 {
  88     for (; __n; --__n)
  89     {
  90         if (eq(*__s, __a))
  91             return __s;
  92         ++__s;
  93     }
  94     return 0;
  95 }
  96
  97 template <class _CharT>
  98 TEST_CONSTEXPR_CXX14 _CharT*
  99 constexpr_char_traits<_CharT>::move(char_type* __s1, const char_type* __s2, size_t __n)
 100 {
 101     char_type* __r = __s1;
 102     if (__s1 < __s2)
 103     {
 104         for (; __n; --__n, ++__s1, ++__s2)
 105             assign(*__s1, *__s2);
 106     }
 107     else if (__s2 < __s1)
 108     {
 109         __s1 += __n;
 110         __s2 += __n;
 111         for (; __n; --__n)
 112             assign(*--__s1, *--__s2);
 113     }
 114     return __r;
 115 }
 116
 117 template <class _CharT>
 118 TEST_CONSTEXPR_CXX14 _CharT*
 119 constexpr_char_traits<_CharT>::copy(char_type* __s1, const char_type* __s2, size_t __n)
 120 {
 121     assert(__s2 < __s1 || __s2 >= __s1+__n);
 122     char_type* __r = __s1;
 123     for (; __n; --__n, ++__s1, ++__s2)
 124         assign(*__s1, *__s2);
 125     return __r;
 126 }
 127
 128 template <class _CharT>
 129 TEST_CONSTEXPR_CXX14 _CharT*
 130 constexpr_char_traits<_CharT>::assign(char_type* __s, size_t __n, char_type __a)
 131 {
 132     char_type* __r = __s;
 133     for (; __n; --__n, ++__s)
 134         assign(*__s, __a);
 135     return __r;
 136 }
 137
 138 #endif // _CONSTEXPR_CHAR_TRAITS