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+/* Retrieve information about a FILE stream.
+ Copyright (C) 2007-2016 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 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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include "freading.h"
+
+#include "stdio-impl.h"
+
+/* Don't use glibc's __freading function in glibc < 2.7, see
+ <http://sourceware.org/bugzilla/show_bug.cgi?id=4359> */
+#if !(HAVE___FREADING && (!defined __GLIBC__ || defined __UCLIBC__ || __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 7)))
+
+bool
+freading (FILE *fp)
+{
+ /* 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_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+ return ((fp->_flags & _IO_NO_WRITES) != 0
+ || ((fp->_flags & (_IO_NO_READS | _IO_CURRENTLY_PUTTING)) == 0
+ && fp->_IO_read_base != NULL));
+# elif defined __sferror || defined __DragonFly__ || defined __ANDROID__
+ /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin, Android */
+ return (fp_->_flags & __SRD) != 0;
+# elif defined __EMX__ /* emx+gcc */
+ return (fp->_flags & _IOREAD) != 0;
+# elif defined __minix /* Minix */
+ return (fp->_flags & _IOREADING) != 0;
+# elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw, NonStop Kernel */
+# if defined __sun /* Solaris */
+ return (fp->_flag & _IOREAD) != 0 && (fp->_flag & _IOWRT) == 0;
+# else
+ return (fp->_flag & _IOREAD) != 0;
+# endif
+# elif defined __UCLIBC__ /* uClibc */
+ return (fp->__modeflags & (__FLAG_READONLY | __FLAG_READING)) != 0;
+# elif defined __QNX__ /* QNX */
+ return ((fp->_Mode & 0x2 /* _MOPENW */) == 0
+ || (fp->_Mode & 0x1000 /* _MREAD */) != 0);
+# elif defined __MINT__ /* Atari FreeMiNT */
+ if (!fp->__mode.__write)
+ return 1;
+ if (!fp->__mode.__read)
+ return 0;
+# ifdef _IO_CURRENTLY_GETTING /* Flag added on 2009-02-28 */
+ return (fp->__flags & _IO_CURRENTLY_GETTING) != 0;
+# else
+ return (fp->__buffer < fp->__get_limit /*|| fp->__bufp == fp->__put_limit ??*/);
+# endif
+# elif defined EPLAN9 /* Plan9 */
+ if (fp->state == 0 /* CLOSED */ || fp->state == 4 /* WR */)
+ return 0;
+ return (fp->state == 3 /* RD */ && (fp->bufl == 0 || fp->rp < fp->wp));
+# else
+# error "Please port gnulib freading.c to your platform!"
+# endif
+}
+
+#endif