# HG changeset patch
# User Bruno Haible <bruno@clisp.org>
# Date 1204201157 -3600
# Node ID 7c1260f0aac3946844623c13461125c22d51d67c
# Parent  4f5ee8490cd3b7ac82e60be409498814b5a985e5
New module 'freadptr'.

diff --git a/ChangeLog b/ChangeLog
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2008-02-28  Bruno Haible  <bruno@clisp.org>
+
+	New module 'freadptr'.
+	* modules/freadptr: New file.
+	* lib/freadptr.h: New file.
+	* lib/freadptr.c: New file.
+	* MODULES.html.sh (File stream based Input/Output): Add freadptr.
+
 2008-02-26  Karl Berry  <karl@freefriends.org>
 
 	Sync from Libtool:
diff --git a/MODULES.html.sh b/MODULES.html.sh
--- a/MODULES.html.sh
+++ b/MODULES.html.sh
@@ -2282,6 +2282,7 @@
   func_module freadable
   func_module freadahead
   func_module freading
+  func_module freadptr
   func_module fwritable
   func_module fwriting
   func_module getpass
diff --git a/lib/freadptr.c b/lib/freadptr.c
new file mode 100644
--- /dev/null
+++ b/lib/freadptr.c
@@ -0,0 +1,54 @@
+/* Retrieve information about a FILE stream.
+   Copyright (C) 2007-2008 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 "freadahead.h"
+
+const char *
+freadptr (FILE *fp)
+{
+  /* Keep this code in sync with freadahead!  */
+#if defined _IO_ferror_unlocked     /* GNU libc, BeOS */
+  return (const char *) fp->_IO_read_ptr;
+#elif defined __sferror             /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
+  return (const char *) fp->_p;
+#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)
+  return (const char *) fp_->_ptr;
+# else
+  return (const char *) fp->_ptr;
+# endif
+#elif defined __UCLIBC__            /* uClibc */
+# ifdef __STDIO_BUFFERS
+  return (const char *) fp->__bufpos;
+# else
+  return NULL;
+# endif
+#elif defined __QNX__               /* QNX */
+  return (const char *) fp->_Next;
+#else
+ #error "Please port gnulib freadptr.c to your platform! Look at the definition of getc, getc_unlocked on your system, then report this to bug-gnulib."
+#endif
+}
diff --git a/lib/freadptr.h b/lib/freadptr.h
new file mode 100644
--- /dev/null
+++ b/lib/freadptr.h
@@ -0,0 +1,40 @@
+/* Retrieve information about a FILE stream.
+   Copyright (C) 2007-2008 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 <stddef.h>
+#include <stdio.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Assuming the stream STREAM is open for reading:
+   Return a pointer to the input buffer of STREAM.
+   If freadahead (STREAM) > 0, the result is a pointer to freadahead (STREAM)
+   bytes.
+   If freadahead (STREAM) == 0, the result is not usable; it may be NULL.
+   In this case, you should use getc (STREAM), fgetc (STREAM), or
+   fread (..., STREAM) to access the input from STREAM.
+
+   The resulting pointer becomes invalid upon any operation on STREAM.
+
+   STREAM must not be wide-character oriented.  */
+
+extern const char * freadptr (FILE *stream);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/modules/freadptr b/modules/freadptr
new file mode 100644
--- /dev/null
+++ b/modules/freadptr
@@ -0,0 +1,23 @@
+Description:
+freadptr() function: Pointer to the input buffer of a stream.
+
+Files:
+lib/freadptr.h
+lib/freadptr.c
+
+Depends-on:
+
+configure.ac:
+
+Makefile.am:
+lib_SOURCES += freadptr.c
+
+Include:
+"freadptr.h"
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
+