1 /* An fseeko() function that, together with fflush(), is POSIX compliant.
2 Copyright (C) 2007-2008 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License along
15 with this program; if not, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
23 /* Get off_t and lseek. */
33 rpl_fseeko (FILE *fp, off_t offset, int whence)
36 /* mingw gives bogus answers rather than failure on non-seekable files. */
37 if (lseek (fileno (fp), 0, SEEK_CUR) == -1)
41 /* These tests are based on fpurge.c. */
42 #if defined _IO_ferror_unlocked /* GNU libc, BeOS */
43 if (fp->_IO_read_end == fp->_IO_read_ptr
44 && fp->_IO_write_ptr == fp->_IO_write_base
45 && fp->_IO_save_base == NULL)
46 #elif defined __sferror /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
47 # if defined __NetBSD__ || defined __OpenBSD__ /* NetBSD, OpenBSD */
48 /* See <http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup>
49 and <http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup> */
50 # define fp_ub ((struct { struct __sbuf _ub; } *) fp->_ext._base)->_ub
51 # else /* FreeBSD, MacOS X, Cygwin */
52 # define fp_ub fp->_ub
54 # if defined __SL64 && defined __SCLE /* Cygwin */
55 if ((fp->_flags & __SL64) == 0)
57 /* Cygwin 1.5.0 through 1.5.24 failed to open stdin in 64-bit
58 mode; but has an fseeko that requires 64-bit mode. */
59 FILE *tmp = fopen ("/dev/null", "r");
63 fp->_seek64 = tmp->_seek64;
67 if (fp->_p == fp->_bf._base
69 && fp->_w == ((fp->_flags & (__SLBF | __SNBF | __SRD)) == 0 /* fully buffered and not currently reading? */
72 && fp_ub._base == NULL)
73 #elif defined __EMX__ /* emx+gcc */
74 if (fp->_ptr == fp->_buffer
77 && fp->_ungetc_count == 0)
78 #elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw */
79 # if defined __sun && defined _LP64 /* Solaris/{SPARC,AMD64} 64-bit */
80 # define fp_ ((struct { unsigned char *_ptr; \
81 unsigned char *_base; \
82 unsigned char *_end; \
87 if (fp_->_ptr == fp_->_base
88 && (fp_->_ptr == NULL || fp_->_cnt == 0))
90 # if defined _SCO_DS /* OpenServer */
95 if (fp->_ptr == fp->_base
96 && (fp->_ptr == NULL || fp->_cnt == 0))
98 #elif defined __UCLIBC__ /* uClibc */
99 if (((fp->__modeflags & __FLAG_WRITING) == 0
100 || fp->__bufpos == fp->__bufstart)
101 && ((fp->__modeflags & (__FLAG_READONLY | __FLAG_READING)) == 0
102 || fp->__bufpos == fp->__bufread))
103 #elif defined __QNX__ /* QNX */
104 if ((fp->_Mode & _MWRITE ? fp->_Next == fp->_Buf : fp->_Next == fp->_Rend)
105 && fp->_Rback == fp->_Back + sizeof (fp->_Back)
106 && fp->_Rsave == NULL)
108 #error "Please port gnulib fseeko.c to your platform! Look at the code in fpurge.c, then report this to bug-gnulib."
111 off_t pos = lseek (fileno (fp), offset, whence);
114 #if defined __sferror /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
115 fp->_flags &= ~__SOFF;
121 #if defined __sferror /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
123 fp->_flags |= __SOFF;
124 fp->_flags &= ~__SEOF;
125 #elif defined __EMX__ /* emx+gcc */
126 fp->_flags &= ~_IOEOF;
127 #elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw */
128 # if defined _SCO_DS /* OpenServer */
129 # define _flag __flag
131 fp->_flag &= ~_IOEOF;
137 return fseeko (fp, offset, whence);