| /* An fseeko() function that, together with fflush(), is POSIX compliant. |
| Copyright (C) 2007-2020 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 2, 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 <stdio.h> |
| |
| /* Get off_t, lseek, _POSIX_VERSION. */ |
| #include <unistd.h> |
| |
| #include "stdio-impl.h" |
| |
| int |
| fseeko (FILE *fp, off_t offset, int whence) |
| #undef fseeko |
| #if !HAVE_FSEEKO |
| # undef fseek |
| # define fseeko fseek |
| #endif |
| #if _GL_WINDOWS_64_BIT_OFF_T |
| # undef fseeko |
| # if HAVE__FSEEKI64 && HAVE_DECL__FSEEKI64 /* msvc, mingw since msvcrt8.0, mingw64 */ |
| # define fseeko _fseeki64 |
| # else /* mingw before msvcrt8.0 */ |
| # define fseeko fseeko64 |
| # endif |
| #endif |
| { |
| #if LSEEK_PIPE_BROKEN |
| /* mingw gives bogus answers rather than failure on non-seekable files. */ |
| if (lseek (fileno (fp), 0, SEEK_CUR) == -1) |
| return EOF; |
| #endif |
| |
| /* These tests are based on fpurge.c. */ |
| #if defined _IO_EOF_SEEN || defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 |
| /* GNU libc, BeOS, Haiku, Linux libc5 */ |
| if (fp->_IO_read_end == fp->_IO_read_ptr |
| && fp->_IO_write_ptr == fp->_IO_write_base |
| && fp->_IO_save_base == NULL) |
| #elif defined __sferror || defined __DragonFly__ || defined __ANDROID__ |
| /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin, Minix 3, Android */ |
| # if defined __SL64 && defined __SCLE /* Cygwin */ |
| if ((fp->_flags & __SL64) == 0) |
| { |
| /* Cygwin 1.5.0 through 1.5.24 failed to open stdin in 64-bit |
| mode; but has an fseeko that requires 64-bit mode. */ |
| FILE *tmp = fopen ("/dev/null", "r"); |
| if (!tmp) |
| return -1; |
| fp->_flags |= __SL64; |
| fp->_seek64 = tmp->_seek64; |
| fclose (tmp); |
| } |
| # endif |
| if (fp_->_p == fp_->_bf._base |
| && fp_->_r == 0 |
| && fp_->_w == ((fp_->_flags & (__SLBF | __SNBF | __SRD)) == 0 /* fully buffered and not currently reading? */ |
| ? fp_->_bf._size |
| : 0) |
| && fp_ub._base == NULL) |
| #elif defined __EMX__ /* emx+gcc */ |
| if (fp->_ptr == fp->_buffer |
| && fp->_rcount == 0 |
| && fp->_wcount == 0 |
| && fp->_ungetc_count == 0) |
| #elif defined __minix /* Minix */ |
| if (fp_->_ptr == fp_->_buf |
| && (fp_->_ptr == NULL || fp_->_count == 0)) |
| #elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw, MSVC, NonStop Kernel, OpenVMS */ |
| if (fp_->_ptr == fp_->_base |
| && (fp_->_ptr == NULL || fp_->_cnt == 0)) |
| #elif defined __UCLIBC__ /* uClibc */ |
| if (((fp->__modeflags & __FLAG_WRITING) == 0 |
| || fp->__bufpos == fp->__bufstart) |
| && ((fp->__modeflags & (__FLAG_READONLY | __FLAG_READING)) == 0 |
| || fp->__bufpos == fp->__bufread)) |
| #elif defined __QNX__ /* QNX */ |
| if ((fp->_Mode & 0x2000 /* _MWRITE */ ? fp->_Next == fp->_Buf : fp->_Next == fp->_Rend) |
| && fp->_Rback == fp->_Back + sizeof (fp->_Back) |
| && fp->_Rsave == NULL) |
| #elif defined __MINT__ /* Atari FreeMiNT */ |
| if (fp->__bufp == fp->__buffer |
| && fp->__get_limit == fp->__bufp |
| && fp->__put_limit == fp->__bufp |
| && !fp->__pushed_back) |
| #elif defined EPLAN9 /* Plan9 */ |
| if (fp->rp == fp->buf |
| && fp->wp == fp->buf) |
| #elif FUNC_FFLUSH_STDIN < 0 && 200809 <= _POSIX_VERSION |
| /* Cross-compiling to some other system advertising conformance to |
| POSIX.1-2008 or later. Assume fseeko and fflush work as advertised. |
| If this assumption is incorrect, please report the bug to |
| bug-gnulib. */ |
| if (0) |
| #else |
| #error "Please port gnulib fseeko.c to your platform! Look at the code in fseeko.c, then report this to bug-gnulib." |
| #endif |
| { |
| /* We get here when an fflush() call immediately preceded this one (or |
| if ftell() has created buffers but no I/O has occurred on a |
| newly-opened stream). We know there are no buffers. */ |
| off_t pos = lseek (fileno (fp), offset, whence); |
| if (pos == -1) |
| { |
| #if defined __sferror || defined __DragonFly__ || defined __ANDROID__ |
| /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin, Minix 3, Android */ |
| fp_->_flags &= ~__SOFF; |
| #endif |
| return -1; |
| } |
| |
| #if defined _IO_EOF_SEEN || defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 |
| /* GNU libc, BeOS, Haiku, Linux libc5 */ |
| fp->_flags &= ~_IO_EOF_SEEN; |
| fp->_offset = pos; |
| #elif defined __sferror || defined __DragonFly__ || defined __ANDROID__ |
| /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin, Minix 3, Android */ |
| # if defined __CYGWIN__ || (defined __NetBSD__ && __NetBSD_Version__ >= 600000000) || defined __minix |
| /* fp_->_offset is typed as an integer. */ |
| fp_->_offset = pos; |
| # else |
| /* fp_->_offset is an fpos_t. */ |
| { |
| /* Use a union, since on NetBSD, the compilation flags |
| determine whether fpos_t is typedef'd to off_t or a struct |
| containing a single off_t member. */ |
| union |
| { |
| fpos_t f; |
| off_t o; |
| } u; |
| u.o = pos; |
| fp_->_offset = u.f; |
| } |
| # endif |
| fp_->_flags |= __SOFF; |
| fp_->_flags &= ~__SEOF; |
| #elif defined __EMX__ /* emx+gcc */ |
| fp->_flags &= ~_IOEOF; |
| #elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw, MSVC, NonStop Kernel, OpenVMS */ |
| fp_->_flag &= ~_IOEOF; |
| #elif defined __MINT__ /* Atari FreeMiNT */ |
| fp->__offset = pos; |
| fp->__eof = 0; |
| #endif |
| return 0; |
| } |
| return fseeko (fp, offset, whence); |
| } |