1 files changed, 75 insertions, 0 deletions
diff --git a/unionfs/ulfs.h b/unionfs/ulfs.h
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+++ b/unionfs/ulfs.h
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+/* Hurd unionfs
+   Copyright (C) 2001, 2002, 2005 Free Software Foundation, Inc.
+   Written by Moritz Schulte <moritz@duesseldorf.ccc.de>.
+
+   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 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+   USA.  */
+
+/* Underlying filesystem management.  */
+
+#ifndef INCLUDED_ULFS_H
+#define INCLUDED_ULFS_H
+
+/* The structure for each registered underlying filesystem.  */
+typedef struct ulfs
+{
+  char *path;
+  int flags;
+  int priority;
+  struct ulfs *next, *prev;
+} ulfs_t;
+
+/* Flags.  */
+
+/* The according ulfs is marked writable.  */
+#define FLAG_ULFS_WRITABLE 0x00000001
+
+/* The start of the ulfs chain.  */
+extern ulfs_t *ulfs_chain_start;
+
+/* The end of the ulfs chain, we need this, to go through the chain in
+   reversed order.  */
+extern ulfs_t *ulfs_chain_end;
+
+/* Number of registered underlying filesystems.  */
+extern unsigned int ulfs_num;
+
+/* The lock protecting the ulfs data structures.  */
+extern struct mutex ulfs_lock;
+
+/* Register a new underlying filesystem.  */
+error_t ulfs_register (char *path, int flags, int priority);
+
+/* Unregister an underlying filesystem.  */
+error_t ulfs_unregister (char *path);
+
+/* Get an ULFS element by it's index.  */
+error_t ulfs_get_num (int num, ulfs_t **ulfs);
+
+/* Removes invalid ulfs entries.  */
+void ulfs_check (void);
+
+#define ulfs_iterate                             \
+  for (ulfs_t *ulfs = (mutex_lock (&ulfs_lock),  \
+		       ulfs_chain_start);          \
+       ulfs || (mutex_unlock (&ulfs_lock), 0);   \
+       ulfs = ulfs->next) 
+
+#define ulfs_iterate_unlocked                    \
+  for (ulfs_t *ulfs = ulfs_chain_start;            \
+       ulfs;                                     \
+       ulfs = ulfs->next)
+
+#endif