1 //
2 // Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
3 //
4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 //
7 // Official repository: https://github.com/boostorg/beast
8 //
9
10 #ifndef BOOST_BEAST_DETAIL_STATIC_STRING_HPP
11 #define BOOST_BEAST_DETAIL_STATIC_STRING_HPP
12
13 #include <boost/beast/core/string.hpp>
14 #include <boost/assert.hpp>
15 #include <iterator>
16 #include <type_traits>
17
18 namespace boost {
19 namespace beast {
20 namespace detail {
21
22 // Because k-ballo said so
23 template<class T>
24 using is_input_iterator =
25 std::integral_constant<bool,
26 ! std::is_integral<T>::value>;
27
28 template<class CharT, class Traits>
29 int
lexicographical_compare(CharT const * s1,std::size_t n1,CharT const * s2,std::size_t n2)30 lexicographical_compare(
31 CharT const* s1, std::size_t n1,
32 CharT const* s2, std::size_t n2)
33 {
34 if(n1 < n2)
35 return Traits::compare(
36 s1, s2, n1) <= 0 ? -1 : 1;
37 if(n1 > n2)
38 return Traits::compare(
39 s1, s2, n2) >= 0 ? 1 : -1;
40 return Traits::compare(s1, s2, n1);
41 }
42
43 template<class CharT, class Traits>
44 int
lexicographical_compare(basic_string_view<CharT,Traits> s1,CharT const * s2,std::size_t n2)45 lexicographical_compare(
46 basic_string_view<CharT, Traits> s1,
47 CharT const* s2, std::size_t n2)
48 {
49 return detail::lexicographical_compare<
50 CharT, Traits>(s1.data(), s1.size(), s2, n2);
51 }
52
53 template<class CharT, class Traits>
54 int
lexicographical_compare(basic_string_view<CharT,Traits> s1,basic_string_view<CharT,Traits> s2)55 lexicographical_compare(
56 basic_string_view<CharT, Traits> s1,
57 basic_string_view<CharT, Traits> s2)
58 {
59 return detail::lexicographical_compare<CharT, Traits>(
60 s1.data(), s1.size(), s2.data(), s2.size());
61 }
62
63 // Maximum number of characters in the decimal
64 // representation of a binary number. This includes
65 // the potential minus sign.
66 //
67 inline
68 std::size_t constexpr
max_digits(std::size_t bytes)69 max_digits(std::size_t bytes)
70 {
71 return static_cast<std::size_t>(
72 bytes * 2.41) + 1 + 1;
73 }
74
75 template<class CharT, class Integer, class Traits>
76 CharT*
raw_to_string(CharT * buf,Integer x,std::true_type)77 raw_to_string(
78 CharT* buf, Integer x, std::true_type)
79 {
80 if(x == 0)
81 {
82 Traits::assign(*--buf, '0');
83 return buf;
84 }
85 if(x < 0)
86 {
87 x = -x;
88 for(;x > 0; x /= 10)
89 Traits::assign(*--buf ,
90 "0123456789"[x % 10]);
91 Traits::assign(*--buf, '-');
92 return buf;
93 }
94 for(;x > 0; x /= 10)
95 Traits::assign(*--buf ,
96 "0123456789"[x % 10]);
97 return buf;
98 }
99
100 template<class CharT, class Integer, class Traits>
101 CharT*
raw_to_string(CharT * buf,Integer x,std::false_type)102 raw_to_string(
103 CharT* buf, Integer x, std::false_type)
104 {
105 if(x == 0)
106 {
107 *--buf = '0';
108 return buf;
109 }
110 for(;x > 0; x /= 10)
111 Traits::assign(*--buf ,
112 "0123456789"[x % 10]);
113 return buf;
114 }
115
116 template<
117 class CharT,
118 class Integer,
119 class Traits = std::char_traits<CharT>>
120 CharT*
121 raw_to_string(CharT* last, std::size_t size, Integer i)
122 {
123 boost::ignore_unused(size);
124 BOOST_ASSERT(size >= max_digits(sizeof(Integer)));
125 return raw_to_string<CharT, Integer, Traits>(
126 last, i, std::is_signed<Integer>{});
127 }
128
129 } // detail
130 } // beast
131 } // boost
132
133 #endif
134