/* Flushing buffers of a FILE stream.
Copyright (C) 2007 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 "fpurge.h"
+#if HAVE___FPURGE /* glibc >= 2.2, Solaris >= 7 */
+# include <stdio_ext.h>
+#endif
+#include <stdlib.h>
+
int
fpurge (FILE *fp)
{
+#if HAVE___FPURGE /* glibc >= 2.2, Solaris >= 7 */
+
+ __fpurge (fp);
+ /* The __fpurge function does not have a return value. */
+ return 0;
+
+#elif HAVE_FPURGE /* FreeBSD, NetBSD, OpenBSD, MacOS X */
+
+ /* Call the system's fpurge function. */
+# undef fpurge
+# if !HAVE_DECL_FPURGE
+ extern int fpurge (FILE *);
+# endif
+ int result = fpurge (fp);
+# if defined __sferror /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
+ if (result == 0)
+ /* Correct the invariants that fpurge broke.
+ <stdio.h> on BSD systems says:
+ "The following always hold: if _flags & __SRD, _w is 0."
+ If this invariant is not fulfilled and the stream is read-write but
+ currently writing, subsequent putc or fputc calls will write directly
+ into the buffer, although they shouldn't be allowed to. */
+ if ((fp->_flags & __SRD) != 0)
+ fp->_w = 0;
+# endif
+ return result;
+
+#else
+
/* Most systems provide FILE as a struct and the necessary bitmask in
<stdio.h>, because they need it for implementing getc() and putc() as
fast macros. */
-#if defined _IO_ferror_unlocked /* GNU libc, BeOS */
+# if defined _IO_ferror_unlocked /* GNU libc, BeOS */
fp->_IO_read_end = fp->_IO_read_ptr;
fp->_IO_write_ptr = fp->_IO_write_base;
+ /* Avoid memory leak when there is an active ungetc buffer. */
+ if (fp->_IO_save_base != NULL)
+ {
+ free (fp->_IO_save_base);
+ fp->_IO_save_base = NULL;
+ }
return 0;
-#elif defined __sferror /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
+# elif defined __sferror /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
fp->_p = fp->_bf._base;
fp->_r = 0;
- fp->_w = ((fp->_flags & (__SLBF | __SNBF)) == 0 /* fully buffered? */
+ fp->_w = ((fp->_flags & (__SLBF | __SNBF | __SRD)) == 0 /* fully buffered and not currently reading? */
? fp->_bf._size
: 0);
+ /* Avoid memory leak when there is an active ungetc buffer. */
+# if defined __NetBSD__ || defined __OpenBSD__ /* NetBSD, OpenBSD */
+ /* See <http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup>
+ and <http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup> */
+# define fp_ub ((struct { struct __sbuf _ub; } *) fp->_ext._base)->_ub
+# else /* FreeBSD, MacOS X, Cygwin */
+# define fp_ub fp->_ub
+# endif
+ if (fp_ub._base != NULL)
+ {
+ if (fp_ub._base != fp->_ubuf)
+ free (fp_ub._base);
+ fp_ub._base = NULL;
+ }
return 0;
-#elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, mingw */
+# elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, mingw */
fp->_ptr = fp->_base;
if (fp->_ptr != NULL)
fp->_cnt = 0;
return 0;
-#else
- #error "Please port gnulib fpurge.c to your platform!"
+# elif defined __UCLIBC__ /* uClibc */
+# ifdef __STDIO_BUFFERS
+ if (fp->__modeflags & __FLAG_WRITING)
+ fp->__bufpos = fp->__bufstart;
+ else if (fp->__modeflags & (__FLAG_READONLY | __FLAG_READING))
+ fp->__bufpos = fp->__bufread;
+# endif
+ return 0;
+# elif defined __QNX__ /* QNX */
+ fp->_Rback = fp->_Back + sizeof (fp->_Back);
+ fp->_Rsave = NULL;
+ if (fp->_Mode & 0x2000 /* _MWRITE */)
+ /* fp->_Buf <= fp->_Next <= fp->_Wend */
+ fp->_Next = fp->_Buf;
+ else
+ /* fp->_Buf <= fp->_Next <= fp->_Rend */
+ fp->_Rend = fp->_Next;
+ return 0;
+# else
+ #error "Please port gnulib fpurge.c to your platform! Look at the definitions of fflush, setvbuf and ungetc on your system, then report this to bug-gnulib."
+# endif
+
#endif
}