Imported Upstream version 1.3.14

[debian/gzip] / lib / freading.c

diff --git a/lib/freading.c b/lib/freading.c
new file mode 100644 (file)
index 0000000..4da0e31
--- /dev/null
+++ b/lib/freading.c
@@ -0,0 +1,64 @@
+/* Retrieve information about a FILE stream.
+   Copyright (C) 2007-2009 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__ || __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__ /* FreeBSD, NetBSD, OpenBSD, DragonFly, MacOS X, Cygwin */
+  return (fp_->_flags & __SRD) != 0;
+#elif defined __EMX__               /* emx+gcc */
+  return (fp->_flags & _IOREAD) != 0;
+#elif defined _IOERR                /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw */
+  return (fp->_flag & _IOREAD) != 0;
+#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
+#else
+ #error "Please port gnulib freading.c to your platform!"
+#endif
+}
+
+#endif