1 // File descriptor layer for filebuf -*- C++ -*-
3 // Copyright (C) 2002, 2003, 2004, 2005, 2009 Free Software Foundation, Inc.
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
25 /** @file ext/stdio_filebuf.h
26 * This file is a GNU extension to the Standard C++ Library.
29 #ifndef _STDIO_FILEBUF_H
30 #define _STDIO_FILEBUF_H 1
32 #pragma GCC system_header
36 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx
)
39 * @brief Provides a layer of compatibility for C/POSIX.
41 * This GNU extension provides extensions for working with standard C
42 * FILE*'s and POSIX file descriptors. It must be instantiated by the
43 * user with the type of character used in the file stream, e.g.,
44 * stdio_filebuf<char>.
46 template<typename _CharT
, typename _Traits
= std::char_traits
<_CharT
> >
47 class stdio_filebuf
: public std::basic_filebuf
<_CharT
, _Traits
>
51 typedef _CharT char_type
;
52 typedef _Traits traits_type
;
53 typedef typename
traits_type::int_type int_type
;
54 typedef typename
traits_type::pos_type pos_type
;
55 typedef typename
traits_type::off_type off_type
;
56 typedef std::size_t size_t;
60 * deferred initialization
62 stdio_filebuf() : std::basic_filebuf
<_CharT
, _Traits
>() {}
65 * @param fd An open file descriptor.
66 * @param mode Same meaning as in a standard filebuf.
67 * @param size Optimal or preferred size of internal buffer, in chars.
69 * This constructor associates a file stream buffer with an open
70 * POSIX file descriptor. The file descriptor will be automatically
71 * closed when the stdio_filebuf is closed/destroyed.
73 stdio_filebuf(int __fd
, std::ios_base::openmode __mode
,
74 size_t __size
= static_cast<size_t>(BUFSIZ
));
77 * @param f An open @c FILE*.
78 * @param mode Same meaning as in a standard filebuf.
79 * @param size Optimal or preferred size of internal buffer, in chars.
80 * Defaults to system's @c BUFSIZ.
82 * This constructor associates a file stream buffer with an open
83 * C @c FILE*. The @c FILE* will not be automatically closed when the
84 * stdio_filebuf is closed/destroyed.
86 stdio_filebuf(std::__c_file
* __f
, std::ios_base::openmode __mode
,
87 size_t __size
= static_cast<size_t>(BUFSIZ
));
90 * Closes the external data stream if the file descriptor constructor
97 * @return The underlying file descriptor.
99 * Once associated with an external data stream, this function can be
100 * used to access the underlying POSIX file descriptor. Note that
101 * there is no way for the library to track what you do with the
102 * descriptor, so be careful.
105 fd() { return this->_M_file
.fd(); }
108 * @return The underlying FILE*.
110 * This function can be used to access the underlying "C" file pointer.
111 * Note that there is no way for the library to track what you do
112 * with the file, so be careful.
115 file() { return this->_M_file
.file(); }
118 template<typename _CharT
, typename _Traits
>
119 stdio_filebuf
<_CharT
, _Traits
>::~stdio_filebuf()
122 template<typename _CharT
, typename _Traits
>
123 stdio_filebuf
<_CharT
, _Traits
>::
124 stdio_filebuf(int __fd
, std::ios_base::openmode __mode
, size_t __size
)
126 this->_M_file
.sys_open(__fd
, __mode
);
129 this->_M_mode
= __mode
;
130 this->_M_buf_size
= __size
;
131 this->_M_allocate_internal_buffer();
132 this->_M_reading
= false;
133 this->_M_writing
= false;
134 this->_M_set_buffer(-1);
138 template<typename _CharT
, typename _Traits
>
139 stdio_filebuf
<_CharT
, _Traits
>::
140 stdio_filebuf(std::__c_file
* __f
, std::ios_base::openmode __mode
,
143 this->_M_file
.sys_open(__f
, __mode
);
146 this->_M_mode
= __mode
;
147 this->_M_buf_size
= __size
;
148 this->_M_allocate_internal_buffer();
149 this->_M_reading
= false;
150 this->_M_writing
= false;
151 this->_M_set_buffer(-1);
155 _GLIBCXX_END_NAMESPACE