1 files changed, 49 insertions, 0 deletions
diff --git a/libnetfs/io-readable.c b/libnetfs/io-readable.c
new file mode 100644
index 00000000..ad6bf3c1
--- /dev/null
+++ b/libnetfs/io-readable.c
@@ -0,0 +1,49 @@
+
+/* 
+   Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+   Written by Michael I. Bushnell, p/BSG.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd 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 GNU Hurd 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., 59 Temple Place - Suite 330, Boston, MA  02111, USA. */
+
+#include <fcntl.h>
+#include "netfs.h"
+#include "io_S.h"
+
+error_t
+netfs_S_io_readable (struct protid *user,
+		     mach_msg_type_number_t *amount)
+{
+  error_t err;
+  
+  if (!user)
+    return EOPNOTSUPP;
+  
+  if (!(user->po->openstat & O_READ))
+    return EINVAL;
+  
+  mutex_lock (&user->po->np->lock);
+  err = netfs_validate_stat (user->po->np, user->user);
+  if (!err)
+    {
+      if (user->po->np->nn_stat.st_size > user->po->filepointer)
+	*amount = user->po->np->nn_stat.st_size - user->po->filepointer;
+      else
+	*amount = 0;
+    }
+  mutex_unlock (&user->po->np->lock);
+  return err;
+}