1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
//-----------------------------------------------------------------------------
// boost detail/templated_streams.hpp header file
// See http://www.boost.org for updates, documentation, and revision history.
//-----------------------------------------------------------------------------
//
// Copyright (c) 2013 John Maddock, Antony Polukhin
//
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_DETAIL_BASIC_POINTERBUF_HPP
#define BOOST_DETAIL_BASIC_POINTERBUF_HPP
// MS compatible compilers support #pragma once
#if defined(_MSC_VER)
# pragma once
#endif
#include "boost/config.hpp"
#include <streambuf>
namespace boost { namespace detail {
//
// class basic_pointerbuf:
// acts as a stream buffer which wraps around a pair of pointers:
//
template <class charT, class BufferT >
class basic_pointerbuf : public BufferT {
protected:
typedef BufferT base_type;
typedef basic_pointerbuf<charT, BufferT> this_type;
typedef typename base_type::int_type int_type;
typedef typename base_type::char_type char_type;
typedef typename base_type::pos_type pos_type;
typedef ::std::streamsize streamsize;
typedef typename base_type::off_type off_type;
public:
basic_pointerbuf() : base_type() { setbuf(0, 0); }
const charT* getnext() { return this->gptr(); }
#ifndef BOOST_NO_USING_TEMPLATE
using base_type::pptr;
using base_type::pbase;
#else
charT* pptr() const { return base_type::pptr(); }
charT* pbase() const { return base_type::pbase(); }
#endif
protected:
// VC mistakenly assumes that `setbuf` and other functions are not referenced.
// Marking those functions with `inline` suppresses the warnings.
// There must be no harm from marking virtual functions as inline: inline virtual
// call can be inlined ONLY when the compiler knows the "exact class".
inline base_type* setbuf(char_type* s, streamsize n);
inline typename this_type::pos_type seekpos(pos_type sp, ::std::ios_base::openmode which);
inline typename this_type::pos_type seekoff(off_type off, ::std::ios_base::seekdir way, ::std::ios_base::openmode which);
private:
basic_pointerbuf& operator=(const basic_pointerbuf&);
basic_pointerbuf(const basic_pointerbuf&);
};
template<class charT, class BufferT>
BufferT*
basic_pointerbuf<charT, BufferT>::setbuf(char_type* s, streamsize n)
{
this->setg(s, s, s + n);
return this;
}
template<class charT, class BufferT>
typename basic_pointerbuf<charT, BufferT>::pos_type
basic_pointerbuf<charT, BufferT>::seekoff(off_type off, ::std::ios_base::seekdir way, ::std::ios_base::openmode which)
{
typedef typename boost::int_t<sizeof(way) * CHAR_BIT>::least cast_type;
if(which & ::std::ios_base::out)
return pos_type(off_type(-1));
std::ptrdiff_t size = this->egptr() - this->eback();
std::ptrdiff_t pos = this->gptr() - this->eback();
charT* g = this->eback();
switch(static_cast<cast_type>(way))
{
case ::std::ios_base::beg:
if((off < 0) || (off > size))
return pos_type(off_type(-1));
else
this->setg(g, g + off, g + size);
break;
case ::std::ios_base::end:
if((off < 0) || (off > size))
return pos_type(off_type(-1));
else
this->setg(g, g + size - off, g + size);
break;
case ::std::ios_base::cur:
{
std::ptrdiff_t newpos = static_cast<std::ptrdiff_t>(pos + off);
if((newpos < 0) || (newpos > size))
return pos_type(off_type(-1));
else
this->setg(g, g + newpos, g + size);
break;
}
default: ;
}
#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable:4244)
#endif
return static_cast<pos_type>(this->gptr() - this->eback());
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif
}
template<class charT, class BufferT>
typename basic_pointerbuf<charT, BufferT>::pos_type
basic_pointerbuf<charT, BufferT>::seekpos(pos_type sp, ::std::ios_base::openmode which)
{
if(which & ::std::ios_base::out)
return pos_type(off_type(-1));
off_type size = static_cast<off_type>(this->egptr() - this->eback());
charT* g = this->eback();
if(off_type(sp) <= size)
{
this->setg(g, g + off_type(sp), g + size);
}
return pos_type(off_type(-1));
}
}} // namespace boost::detail
#endif // BOOST_DETAIL_BASIC_POINTERBUF_HPP
|