NAME
puffs_path —
puffs pathbuilding
routines
LIBRARY
puffs Convenience Library (libpuffs, -lpuffs)
SYNOPSIS
#include <puffs.h>
int
pu_pathbuild_fn(
struct puffs_usermount
*pu,
const struct puffs_pathobj *po_dir,
const struct puffs_pathobj *po_comp,
size_t offset,
struct puffs_pathobj
*po_new);
int
pu_pathtransform_fn(
struct puffs_usermount
*pu,
const struct puffs_pathobj *po_base,
const struct puffs_cn *pcn,
struct
puffs_pathobj *po_new);
int
pu_pathcmp_fn(
struct puffs_usermount
*pu,
struct puffs_pathobj *po1,
struct puffs_pathobj *po2,
size_t
checklen,
int checkprefix);
void
pu_pathfree_fn(
struct
puffs_usermount *pu,
struct
puffs_pathobj *po);
int
pu_namemod_fn(
struct puffs_usermount
*pu,
struct puffs_pathobj *po_dir,
struct puffs_cn *pcn);
struct puffs_pathobj *
puffs_getrootpathobj(
struct
puffs_usermount *pu);
DESCRIPTION
The puffs library has the ability to provide full pathnames for backends which
require them. Normal file systems should be constructed without the file
system node tied to a file name and should not used routines described herein.
An example of a file system where the backend requires filenames is
mount_psshfs(8).
The features described here are enabled by passing
PUFFS_FLAG_BUILDPATH
to
puffs_init(). This facility requires to use puffs nodes to
store the contents of the pathname. Either the address of the operation cookie
must directly be that of the puffs node, or
puffs_set_cmap()
must be used to set a mapping function from the cookie to the puffs node
associated with the cookie. Finally, the root node for the file system must be
set using
puffs_setroot() and the root path object retrieved
using
puffs_getrootpathobj() and initialized.
There are two different places a filename can be retrieved from. It is available
for each puffs node after the node has been registered with the framework,
i.e.
after the routine creating the node returns. In other
words, there is a window between the node is created and when the pathname is
available and multithreaded file systems must take this into account. The
second place where a pathname is available is from the componentname
struct puffs_pcn in operations which are passed one.
These can be retrieved using the convenience macros
PNPATH()
and
PCNPATH() for node and componentname, respectively. The
type of object they return is
void *.
By default the framework manages "regular" filenames, which consist of
directory names separated by "/" and a final component. If the file
system wishes to use pathnames of this format, all it has to do it enable the
feature. Everything else, including bookkeeping for node and directory
renames, is done by the library. The callback routines described next provide
the ability to build non-standard pathnames. A
pu_foo_fn()
callback is set using the
puffs_set_foo() routine.
This manual page is still unfinished. Please take a number and wait in line.
SEE ALSO
puffs(3),
puffs_node(3),
mount_psshfs(8),
mount_sysctlfs(8)