Merge procfs into the Hurd repository

1 files changed, 99 insertions, 0 deletions

diff --git a/procfs/procfs.h b/procfs/procfs.h
new file mode 100644
index 00000000..d04bbad7
--- /dev/null
+++ b/procfs/procfs.h
@@ -0,0 +1,99 @@
+/* Hurd /proc filesystem, basic infrastructure.
+   Copyright (C) 2010 Free Software Foundation, Inc.
+
+   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., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include <hurd/hurd_types.h>
+#include <hurd/netfs.h>
+
+
+/* Interface for the procfs side. */
+
+/* Any of these callback functions can be omitted, in which case
+   reasonable defaults will be used.  The initial file mode and type
+   depend on whether a lookup function is provided, but can be
+   overridden in update_stat().  */
+struct procfs_node_ops
+{
+  /* Fetch the contents of a node.  A pointer to the contents should be
+     returned in *CONTENTS and their length in *CONTENTS_LEN.  The exact
+     nature of these data depends on whether the node is a regular file,
+     symlink or directory, as determined by the file mode in
+     netnode->nn_stat.  For regular files and symlinks, they are what
+     you would expect; for directories, they are an argz vector of the
+     names of the entries.  If upon return, *CONTENTS_LEN is negative or
+     unchanged, the call is considered to have failed because of a memory
+     allocation error.  */
+  error_t (*get_contents) (void *hook, char **contents, ssize_t *contents_len);
+  void (*cleanup_contents) (void *hook, char *contents, ssize_t contents_len);
+
+  /* Lookup NAME in this directory, and store the result in *np.  The
+     returned node should be created by lookup() using procfs_make_node() 
+     or a derived function.  Note that the parent will be kept alive as
+     long as the child exists, so you can safely reference the parent's
+     data from the child.  You may want to consider locking if there's
+     any mutation going on, though.  */
+  error_t (*lookup) (void *hook, const char *name, struct node **np);
+
+  /* Destroy this node.  */
+  void (*cleanup) (void *hook);
+
+  /* Get the passive translator record.  */
+  error_t (*get_translator) (void *hook, char **argz, size_t *argz_len);
+};
+
+/* These helper functions can be used as procfs_node_ops.cleanup_contents. */
+void procfs_cleanup_contents_with_free (void *, char *, ssize_t);
+void procfs_cleanup_contents_with_vm_deallocate (void *, char *, ssize_t);
+
+/* Create a new node and return it.  Returns NULL if it fails to allocate
+   enough memory.  In this case, ops->cleanup will be invoked.  */
+struct node *procfs_make_node (const struct procfs_node_ops *ops, void *hook);
+
+/* Set the owner of the node NP.  Must be called right after the node
+   has been created.  */
+void procfs_node_chown (struct node *np, uid_t owner);
+
+/* Set the permission bits of the node NP.  Must be called right after
+   the node has been created.  */
+void procfs_node_chmod (struct node *np, mode_t mode);
+
+/* Set the type of the node NP.  If type is S_IFLNK, appropriate
+   permission bits will be set as well.  Must be called right after the
+   node has been created.  */
+void procfs_node_chtype (struct node *np, mode_t type);
+
+
+/* Interface for the libnetfs side. */
+
+/* Get the inode number which will be given to a child of NP named FILENAME.
+   This allows us to retreive them for readdir() without creating the
+   corresponding child nodes.  */
+ino64_t procfs_make_ino (struct node *np, const char *filename);
+
+/* Forget the current cached contents for the node.  This is done before reads
+   from offset 0, to ensure that the data are recent even for utilities such as
+   top which keep some nodes open.  */
+void procfs_refresh (struct node *np);
+
+error_t procfs_get_contents (struct node *np, char **data, ssize_t *data_len);
+error_t procfs_lookup (struct node *np, const char *name, struct node **npp);
+void procfs_cleanup (struct node *np);
+
+/* Get the passive translator record if any.  */
+error_t procfs_get_translator (struct node *np, char **argz, size_t *argz_len);
+