| /* An lseek() function that detects pipes. |
| Copyright (C) 2007, 2009-2021 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 |
| } |