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// Wrapper of C-language FILE struct -*- C++ -*-
// Copyright (C) 2000, 2001, 2002, 2003, 2004, 2006
// 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// 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
//
#include <bits/basic_file.h>
#include <fcntl.h>
#include <errno.h>
#ifdef _GLIBCXX_HAVE_POLL
#include <poll.h>
#endif
// Pick up ioctl on Solaris 2.8
#ifdef _GLIBCXX_HAVE_UNISTD_H
#include <unistd.h>
#endif
// Pick up FIONREAD on Solaris 2
#ifdef _GLIBCXX_HAVE_SYS_IOCTL_H
#define BSD_COMP
#include <sys/ioctl.h>
#endif
// Pick up FIONREAD on Solaris 2.5.
#ifdef _GLIBCXX_HAVE_SYS_FILIO_H
#include <sys/filio.h>
#endif
#ifdef _GLIBCXX_HAVE_SYS_UIO_H
#include <sys/uio.h>
#endif
#if defined(_GLIBCXX_HAVE_S_ISREG) || defined(_GLIBCXX_HAVE_S_IFREG)
# include <sys/stat.h>
# ifdef _GLIBCXX_HAVE_S_ISREG
# define _GLIBCXX_ISREG(x) S_ISREG(x)
# else
# define _GLIBCXX_ISREG(x) (((x) & S_IFMT) == S_IFREG)
# endif
#endif
#include <limits> // For <off_t>::max() and min() and <streamsize>::max()
namespace
{
// Map ios_base::openmode flags to a string for use in fopen().
// Table of valid combinations as given in [lib.filebuf.members]/2.
static const char*
fopen_mode(std::ios_base::openmode mode)
{
enum
{
in = std::ios_base::in,
out = std::ios_base::out,
trunc = std::ios_base::trunc,
app = std::ios_base::app,
binary = std::ios_base::binary
};
switch (mode & (in|out|trunc|app|binary))
{
case ( out ): return "w";
case ( out |app ): return "a";
case ( out|trunc ): return "w";
case (in ): return "r";
case (in|out ): return "r+";
case (in|out|trunc ): return "w+";
// Extension to Table 92.
case (in|out |app ): return "a+";
case ( out |binary): return "wb";
case ( out |app|binary): return "ab";
case ( out|trunc |binary): return "wb";
case (in |binary): return "rb";
case (in|out |binary): return "r+b";
case (in|out|trunc |binary): return "w+b";
// Extension to Table 92.
case (in|out |app|binary): return "a+b";
default: return 0; // invalid
}
}
// Wrapper handling partial write.
static std::streamsize
xwrite(int __fd, const char* __s, std::streamsize __n)
{
std::streamsize __nleft = __n;
for (;;)
{
const std::streamsize __ret = write(__fd, __s, __nleft);
if (__ret == -1L && errno == EINTR)
continue;
if (__ret == -1L)
break;
__nleft -= __ret;
if (__nleft == 0)
break;
__s += __ret;
}
return __n - __nleft;
}
#ifdef _GLIBCXX_HAVE_WRITEV
// Wrapper handling partial writev.
static std::streamsize
xwritev(int __fd, const char* __s1, std::streamsize __n1,
const char* __s2, std::streamsize __n2)
{
std::streamsize __nleft = __n1 + __n2;
std::streamsize __n1_left = __n1;
struct iovec __iov[2];
__iov[1].iov_base = const_cast<char*>(__s2);
__iov[1].iov_len = __n2;
for (;;)
{
__iov[0].iov_base = const_cast<char*>(__s1);
__iov[0].iov_len = __n1_left;
const std::streamsize __ret = writev(__fd, __iov, 2);
if (__ret == -1L && errno == EINTR)
continue;
if (__ret == -1L)
break;
__nleft -= __ret;
if (__nleft == 0)
break;
const std::streamsize __off = __ret - __n1_left;
if (__off >= 0)
{
__nleft -= xwrite(__fd, __s2 + __off, __n2 - __off);
break;
}
__s1 += __ret;
__n1_left -= __ret;
}
return __n1 + __n2 - __nleft;
}
#endif
} // anonymous namespace
_GLIBCXX_BEGIN_NAMESPACE(std)
// Definitions for __basic_file<char>.
__basic_file<char>::__basic_file(__c_lock* /*__lock*/)
: _M_cfile(NULL), _M_cfile_created(false) { }
__basic_file<char>::~__basic_file()
{ this->close(); }
__basic_file<char>*
__basic_file<char>::sys_open(__c_file* __file, ios_base::openmode)
{
__basic_file* __ret = NULL;
if (!this->is_open() && __file)
{
int __err;
errno = 0;
do
__err = this->sync();
while (__err && errno == EINTR);
if (!__err)
{
_M_cfile = __file;
_M_cfile_created = false;
__ret = this;
}
}
return __ret;
}
__basic_file<char>*
__basic_file<char>::sys_open(int __fd, ios_base::openmode __mode)
{
__basic_file* __ret = NULL;
const char* __c_mode = fopen_mode(__mode);
if (__c_mode && !this->is_open() && (_M_cfile = fdopen(__fd, __c_mode)))
{
char* __buf = NULL;
_M_cfile_created = true;
if (__fd == 0)
setvbuf(_M_cfile, __buf, _IONBF, 0);
__ret = this;
}
return __ret;
}
__basic_file<char>*
__basic_file<char>::open(const char* __name, ios_base::openmode __mode,
int /*__prot*/)
{
__basic_file* __ret = NULL;
const char* __c_mode = fopen_mode(__mode);
if (__c_mode && !this->is_open())
{
#ifdef _GLIBCXX_USE_LFS
if ((_M_cfile = fopen64(__name, __c_mode)))
#else
if ((_M_cfile = fopen(__name, __c_mode)))
#endif
{
_M_cfile_created = true;
__ret = this;
}
}
return __ret;
}
bool
__basic_file<char>::is_open() const
{ return _M_cfile != 0; }
int
__basic_file<char>::fd()
{ return fileno(_M_cfile); }
__c_file*
__basic_file<char>::file()
{ return _M_cfile; }
__basic_file<char>*
__basic_file<char>::close()
{
__basic_file* __ret = static_cast<__basic_file*>(NULL);
if (this->is_open())
{
int __err = 0;
if (_M_cfile_created)
{
// In general, no need to zero errno in advance if checking
// for error first. However, C89/C99 (at variance with IEEE
// 1003.1, f.i.) do not mandate that fclose must set errno
// upon error.
errno = 0;
do
__err = fclose(_M_cfile);
while (__err && errno == EINTR);
}
_M_cfile = 0;
if (!__err)
__ret = this;
}
return __ret;
}
streamsize
__basic_file<char>::xsgetn(char* __s, streamsize __n)
{
streamsize __ret;
do
__ret = read(this->fd(), __s, __n);
while (__ret == -1L && errno == EINTR);
return __ret;
}
streamsize
__basic_file<char>::xsputn(const char* __s, streamsize __n)
{ return xwrite(this->fd(), __s, __n); }
streamsize
__basic_file<char>::xsputn_2(const char* __s1, streamsize __n1,
const char* __s2, streamsize __n2)
{
streamsize __ret = 0;
#ifdef _GLIBCXX_HAVE_WRITEV
__ret = xwritev(this->fd(), __s1, __n1, __s2, __n2);
#else
if (__n1)
__ret = xwrite(this->fd(), __s1, __n1);
if (__ret == __n1)
__ret += xwrite(this->fd(), __s2, __n2);
#endif
return __ret;
}
streamoff
__basic_file<char>::seekoff(streamoff __off, ios_base::seekdir __way)
{
#ifdef _GLIBCXX_USE_LFS
return lseek64(this->fd(), __off, __way);
#else
if (__off > numeric_limits<off_t>::max()
|| __off < numeric_limits<off_t>::min())
return -1L;
return lseek(this->fd(), __off, __way);
#endif
}
int
__basic_file<char>::sync()
{ return fflush(_M_cfile); }
streamsize
__basic_file<char>::showmanyc()
{
#ifdef FIONREAD
// Pipes and sockets.
#ifdef _GLIBCXX_FIONREAD_TAKES_OFF_T
off_t __num = 0;
#else
int __num = 0;
#endif
int __r = ioctl(this->fd(), FIONREAD, &__num);
if (!__r && __num >= 0)
return __num;
#endif
#ifdef _GLIBCXX_HAVE_POLL
// Cheap test.
struct pollfd __pfd[1];
__pfd[0].fd = this->fd();
__pfd[0].events = POLLIN;
if (poll(__pfd, 1, 0) <= 0)
return 0;
#endif
#if defined(_GLIBCXX_HAVE_S_ISREG) || defined(_GLIBCXX_HAVE_S_IFREG)
// Regular files.
#ifdef _GLIBCXX_USE_LFS
struct stat64 __buffer;
const int __err = fstat64(this->fd(), &__buffer);
if (!__err && _GLIBCXX_ISREG(__buffer.st_mode))
{
const streamoff __off = __buffer.st_size - lseek64(this->fd(), 0,
ios_base::cur);
return std::min(__off, streamoff(numeric_limits<streamsize>::max()));
}
#else
struct stat __buffer;
const int __err = fstat(this->fd(), &__buffer);
if (!__err && _GLIBCXX_ISREG(__buffer.st_mode))
return __buffer.st_size - lseek(this->fd(), 0, ios_base::cur);
#endif
#endif
return 0;
}
_GLIBCXX_END_NAMESPACE