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PUFFS_PATH(3)	      DragonFly Library Functions Manual	 PUFFS_PATH(3)

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 path-
     name is available and multithreaded file systems must take this into
     account.  The second place where a pathname is available is from the com-
     ponentname 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 sys-
     tem wishes to use pathnames of this format, all it has to do it enable
     the feature.  Everything else, including bookkeeping for node and direc-
     tory 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)

DragonFly 5.5		       February 5, 2012 		 DragonFly 5.5