/* Retrieve information about a FILE stream.
- Copyright (C) 2007 Free Software Foundation, Inc.
+ Copyright (C) 2007-2010 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ 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.
+ the Free Software Foundation; either version 3 of the License, 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, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include "freadahead.h"
+#include <stdlib.h>
+#include "stdio-impl.h"
+
size_t
freadahead (FILE *fp)
{
-#if defined _IO_ferror_unlocked /* GNU libc, BeOS */
+#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
if (fp->_IO_write_ptr > fp->_IO_write_base)
return 0;
- return fp->_IO_read_end - fp->_IO_read_ptr;
-#elif defined __sferror /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
- if ((fp->_flags & __SWR) != 0 || fp->_r < 0)
+ return (fp->_IO_read_end - fp->_IO_read_ptr)
+ + (fp->_flags & _IO_IN_BACKUP ? fp->_IO_save_end - fp->_IO_save_base :
+ 0);
+#elif defined __sferror || defined __DragonFly__ /* FreeBSD, NetBSD, OpenBSD, DragonFly, MacOS X, Cygwin */
+ if ((fp_->_flags & __SWR) != 0 || fp_->_r < 0)
return 0;
- return fp->_r;
-#elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, mingw */
-# if defined __sun && defined _LP64 /* Solaris/{SPARC,AMD64} 64-bit */
-# define fp_ ((struct { unsigned char *_ptr; \
- unsigned char *_base; \
- unsigned char *_end; \
- long _cnt; \
- int _file; \
- unsigned int _flag; \
- } *) fp)
+# if defined __DragonFly__
+ return __sreadahead (fp);
+# else
+ return fp_->_r
+ + (HASUB (fp) ? fp_->_ur : 0);
+# endif
+#elif defined __EMX__ /* emx+gcc */
+ if ((fp->_flags & _IOWRT) != 0)
+ return 0;
+ /* Note: fp->_ungetc_count > 0 implies fp->_rcount <= 0,
+ fp->_ungetc_count = 0 implies fp->_rcount >= 0. */
+ /* equivalent to
+ (fp->_ungetc_count == 0 ? fp->_rcount : fp->_ungetc_count - fp->_rcount) */
+ return (fp->_rcount > 0 ? fp->_rcount : fp->_ungetc_count - fp->_rcount);
+#elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw */
if ((fp_->_flag & _IOWRT) != 0)
return 0;
return fp_->_cnt;
-# else
- if ((fp->_flag & _IOWRT) != 0)
- return 0;
- return fp->_cnt;
-# endif
#elif defined __UCLIBC__ /* uClibc */
# ifdef __STDIO_BUFFERS
if (fp->__modeflags & __FLAG_WRITING)
return 0;
- return fp->__bufread - fp->__bufpos;
+ return (fp->__bufread - fp->__bufpos)
+ + (fp->__modeflags & __FLAG_UNGOT ? 1 : 0);
# else
return 0;
# endif
#elif defined __QNX__ /* QNX */
- if ((fp->_Mode & _MWRITE) != 0)
+ if ((fp->_Mode & 0x2000 /* _MWRITE */) != 0)
return 0;
- /* fp->_Buf <= fp->_Next <= fp->_Rend */
- return fp->_Rend - fp->_Next;
+ /* fp->_Buf <= fp->_Next <= fp->_Rend,
+ and fp->_Rend may be overridden by fp->_Rsave. */
+ return ((fp->_Rsave ? fp->_Rsave : fp->_Rend) - fp->_Next)
+ + (fp->_Mode & 0x4000 /* _MBYTE */
+ ? (fp->_Back + sizeof (fp->_Back)) - fp->_Rback
+ : 0);
+#elif defined __MINT__ /* Atari FreeMiNT */
+ if (!fp->__mode.__read)
+ return 0;
+ return (fp->__pushed_back
+ ? fp->__get_limit - fp->__pushback_bufp + 1
+ : fp->__get_limit - fp->__bufp);
+#elif defined SLOW_BUT_NO_HACKS /* users can define this */
+ abort ();
+ return 0;
#else
- #error "Please port gnulib freadahead.c to your platform! Look at the definition of fflush, fread on your system, then report this to bug-gnulib."
+ #error "Please port gnulib freadahead.c to your platform! Look at the definition of fflush, fread, ungetc on your system, then report this to bug-gnulib."
#endif
}