gcc/libstdc++-v3/config/io/basic_file_stdio.h

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// Wrapper of C-language FILE struct -*- C++ -*-
// Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING. If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
//
// ISO C++ 14882: 27.8 File-based streams
//
/** @file basic_file.h
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
*/
#ifndef _CPP_BASIC_FILE
#define _CPP_BASIC_FILE 1
#pragma GCC system_header
#include <bits/c++config.h>
#include <ios>
porting.texi: Add documentation about libstdc++-v3-specific macros that are currently... libstdc++/2071 * porting.texi: Add documentation about libstdc++-v3-specific macros that are currently included in os_defines.h files. * config/basic_file_stdio.h (sys_getc): New method. (sys_ungetc): New method. * include/bits/basic_file.h: (sys_getc): New method signature. (sys_ungetc): New method signature. * include/bits/fstream.tcc (underflow): Add conditional code paths which avoid using short seeks on streams (especially useful when the stream might be interactive or a pipe). At the moment, this alternate path only avoids seeking when the ``buffer size'' of underflow() is 1 since the C standard only guarantees buffer space for one ungetc (this technique could be extended since *-*-solaris* supports buffering for 4 calls to ungetc and *-*-*bsd* supports buffering limited only by memory resources). Also, _GLIBCPP_AVOID_FSEEK must be defined in a port's os_defines.h file for this alternate path to even be considered. As a bonus, the idiom of using getc/ungetc requires no system calls whereas fseek maps to one or two system call(s) on many platforms. * config/os/bsd/freebsd/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Define it. * config/os/solaris/solaris2.5/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.6/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.7/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. From-SVN: r43278
2001-06-13 07:09:09 +08:00
namespace std
{
// Generic declaration.
porting.texi: Add documentation about libstdc++-v3-specific macros that are currently... libstdc++/2071 * porting.texi: Add documentation about libstdc++-v3-specific macros that are currently included in os_defines.h files. * config/basic_file_stdio.h (sys_getc): New method. (sys_ungetc): New method. * include/bits/basic_file.h: (sys_getc): New method signature. (sys_ungetc): New method signature. * include/bits/fstream.tcc (underflow): Add conditional code paths which avoid using short seeks on streams (especially useful when the stream might be interactive or a pipe). At the moment, this alternate path only avoids seeking when the ``buffer size'' of underflow() is 1 since the C standard only guarantees buffer space for one ungetc (this technique could be extended since *-*-solaris* supports buffering for 4 calls to ungetc and *-*-*bsd* supports buffering limited only by memory resources). Also, _GLIBCPP_AVOID_FSEEK must be defined in a port's os_defines.h file for this alternate path to even be considered. As a bonus, the idiom of using getc/ungetc requires no system calls whereas fseek maps to one or two system call(s) on many platforms. * config/os/bsd/freebsd/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Define it. * config/os/solaris/solaris2.5/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.6/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.7/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. From-SVN: r43278
2001-06-13 07:09:09 +08:00
template<typename _CharT>
class __basic_file;
porting.texi: Add documentation about libstdc++-v3-specific macros that are currently... libstdc++/2071 * porting.texi: Add documentation about libstdc++-v3-specific macros that are currently included in os_defines.h files. * config/basic_file_stdio.h (sys_getc): New method. (sys_ungetc): New method. * include/bits/basic_file.h: (sys_getc): New method signature. (sys_ungetc): New method signature. * include/bits/fstream.tcc (underflow): Add conditional code paths which avoid using short seeks on streams (especially useful when the stream might be interactive or a pipe). At the moment, this alternate path only avoids seeking when the ``buffer size'' of underflow() is 1 since the C standard only guarantees buffer space for one ungetc (this technique could be extended since *-*-solaris* supports buffering for 4 calls to ungetc and *-*-*bsd* supports buffering limited only by memory resources). Also, _GLIBCPP_AVOID_FSEEK must be defined in a port's os_defines.h file for this alternate path to even be considered. As a bonus, the idiom of using getc/ungetc requires no system calls whereas fseek maps to one or two system call(s) on many platforms. * config/os/bsd/freebsd/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Define it. * config/os/solaris/solaris2.5/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.6/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.7/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. From-SVN: r43278
2001-06-13 07:09:09 +08:00
// Specialization.
template<>
class __basic_file<char>
porting.texi: Add documentation about libstdc++-v3-specific macros that are currently... libstdc++/2071 * porting.texi: Add documentation about libstdc++-v3-specific macros that are currently included in os_defines.h files. * config/basic_file_stdio.h (sys_getc): New method. (sys_ungetc): New method. * include/bits/basic_file.h: (sys_getc): New method signature. (sys_ungetc): New method signature. * include/bits/fstream.tcc (underflow): Add conditional code paths which avoid using short seeks on streams (especially useful when the stream might be interactive or a pipe). At the moment, this alternate path only avoids seeking when the ``buffer size'' of underflow() is 1 since the C standard only guarantees buffer space for one ungetc (this technique could be extended since *-*-solaris* supports buffering for 4 calls to ungetc and *-*-*bsd* supports buffering limited only by memory resources). Also, _GLIBCPP_AVOID_FSEEK must be defined in a port's os_defines.h file for this alternate path to even be considered. As a bonus, the idiom of using getc/ungetc requires no system calls whereas fseek maps to one or two system call(s) on many platforms. * config/os/bsd/freebsd/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Define it. * config/os/solaris/solaris2.5/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.6/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.7/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. From-SVN: r43278
2001-06-13 07:09:09 +08:00
{
// Underlying data source/sink.
__c_file_type* _M_cfile;
// True iff we opened _M_cfile, and thus must close it ourselves.
bool _M_cfile_created;
public:
__basic_file(__c_lock* __lock = 0);
void
_M_open_mode(ios_base::openmode __mode, int& __p_mode, int& __rw_mode,
char* __c_mode);
__basic_file*
open(const char* __name, ios_base::openmode __mode, int __prot = 0664);
__basic_file*
sys_open(__c_file_type* __file, ios_base::openmode __mode);
char
sys_getc();
char
sys_ungetc(char);
__basic_file*
close();
bool
is_open();
int
fd();
~__basic_file();
streamsize
xsputn(const char* __s, streamsize __n);
streamsize
xsgetn(char* __s, streamsize __n);
streamoff
seekoff(streamoff __off, ios_base::seekdir __way,
ios_base::openmode __mode = ios_base::in | ios_base::out);
streamoff
seekpos(streamoff __pos,
ios_base::openmode __mode = ios_base::in | ios_base::out);
int
sync();
};
} // namespace std
#endif // _CPP_BASIC_FILE