72 lines
1.9 KiB
C
72 lines
1.9 KiB
C
|
/* An lseek() function that detects pipes.
|
||
|
|
Copyright (C) 2007, 2009-2020 Free Software Foundation, Inc.
|
||
|
|
|
||
|
|
This program 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 3, or (at your option)
|
||
|
|
any later version.
|
||
|
|
|
||
|
|
This program 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 program; if not, see <https://www.gnu.org/licenses/>. */
|
||
|
|
|
||
|
|
#include <config.h>
|
||
|
|
|
||
|
|
/* Specification. */
|
||
|
|
#include <unistd.h>
|
||
|
|
|
||
|
|
#if defined _WIN32 && ! defined __CYGWIN__
|
||
|
|
/* Windows platforms. */
|
||
|
|
/* Get GetFileType. */
|
||
|
|
# include <windows.h>
|
||
|
|
/* Get _get_osfhandle. */
|
||
|
|
# if GNULIB_MSVC_NOTHROW
|
||
|
|
# include "msvc-nothrow.h"
|
||
|
|
# else
|
||
|
|
# include <io.h>
|
||
|
|
# endif
|
||
|
|
#else
|
||
|
|
# include <sys/stat.h>
|
||
|
|
#endif
|
||
|
|
#include <errno.h>
|
||
|
|
|
||
|
|
#undef lseek
|
||
|
|
|
||
|
|
off_t
|
||
|
|
rpl_lseek (int fd, off_t offset, int whence)
|
||
|
|
{
|
||
|
|
#if defined _WIN32 && ! defined __CYGWIN__
|
||
|
|
/* mingw lseek mistakenly succeeds on pipes, sockets, and terminals. */
|
||
|
|
HANDLE h = (HANDLE) _get_osfhandle (fd);
|
||
|
|
if (h == INVALID_HANDLE_VALUE)
|
||
|
|
{
|
||
|
|
errno = EBADF;
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
if (GetFileType (h) != FILE_TYPE_DISK)
|
||
|
|
{
|
||
|
|
errno = ESPIPE;
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
#else
|
||
|
|
/* BeOS lseek mistakenly succeeds on pipes... */
|
||
|
|
struct stat statbuf;
|
||
|
|
if (fstat (fd, &statbuf) < 0)
|
||
|
|
return -1;
|
||
|
|
if (!S_ISREG (statbuf.st_mode))
|
||
|
|
{
|
||
|
|
errno = ESPIPE;
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
#if _GL_WINDOWS_64_BIT_OFF_T || (defined __MINGW32__ && defined _FILE_OFFSET_BITS && (_FILE_OFFSET_BITS == 64))
|
||
|
|
return _lseeki64 (fd, offset, whence);
|
||
|
|
#else
|
||
|
|
return lseek (fd, offset, whence);
|
||
|
|
#endif
|
||
|
|
}
|