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diff --git a/doc/filesystem/patheval.t b/doc/filesystem/patheval.t deleted file mode 100644 index 37d1a9a5e6..0000000000 --- a/doc/filesystem/patheval.t +++ /dev/null @@ -1,106 +0,0 @@ -@c -@c COPYRIGHT (c) 1988-2002. -@c On-Line Applications Research Corporation (OAR). -@c All rights reserved. - -@chapter Pathname Evaluation - -This chapter describes the pathname evaluation process for the -RTEMS Filesystem Infrastructure. - -@example -XXX Include graphic of the path evaluation process -@end example - -@section Pathname Evaluation Handlers - -There are two pathname evaluation routines. The handler patheval() -is called to find, verify privlages on and return information on a node -that exists. The handler evalformake() is called to find, verify -permissions, and return information on a node that is to become a parent. -Additionally, evalformake() returns a pointer to the start of the name of -the new node to be created. - -Pathname evaluation is specific to a filesystem. -Each filesystem is required to provide both a patheval() and an evalformake() -routine. Both of these routines gets a name to evaluate and a node indicating -where to start the evaluation. - -@section Crossing a Mount Point During Path Evaluation - -If the filesystem supports the mount command, the evaluate routines -must handle crossing the mountpoint. The evaluate routine should evaluate -the name upto the first directory node where the new filesystem is mounted. -The filesystem may process terminator characters prior to calling the -evaluate routine for the new filesystem. A pointer to the portion of the -name which has not been evaluated along with the root node of the new -file system ( gotten from the mount table entry ) is passed to the correct -mounted filesystem evaluate routine. - - -@section The rtems_filesystem_location_info_t Structure - -The @code{rtems_filesystem_location_info_t} structure contains all information -necessary for identification of a node. - -The generic rtems filesystem code defines two global -rtems_filesystem_location_info_t structures, the -@code{rtems_filesystem_root} and the @code{rtems_filesystem_current}. -Both are initially defined to be the root node of the base filesystem. -Once the chdir command is correctly used the @code{rtems_filesystem_current} -is set to the location specified by the command. - -The filesystem generic code peeks at the first character in the name to be -evaluated. If this character is a valid seperator, the -@code{rtems_filesystem_root} is used as the node to start the evaluation -with. Otherwise, the @code{rtems_filesystem_current} node is used as the -node to start evaluating with. Therefore, a valid -rtems_filesystem_location_info_t is given to the evaluate routine to start -evaluation with. The evaluate routines are then responsible for making -any changes necessary to this structure to correspond to the name being -parsed. - -@example -struct rtems_filesystem_location_info_tt @{ - void *node_access; - rtems_filesystem_file_handlers_r *handlers; - rtems_filesystem_operations_table *ops; - rtems_filesystem_mount_table_entry_t *mt_entry; -@}; -@end example - -@table @b - -@item node_access -This element is filesystem specific. A filesystem can define and store -any information necessary to identify a node at this location. This element -is normally filled in by the filesystem's evaluate routine. For the -filesystem's root node, the filesystem's initilization routine should -fill this in, and it should remain valid until the instance of the -filesystem is unmounted. - -@item handlers -This element is defined as a set of routines that may change within a -given filesystem based upon node type. For example a directory and a -memory file may have to completely different read routines. This element -is set to an initialization state defined by the mount table, and may -be set to the desired state by the evaluation routines. - -@item ops -This element is defined as a set of routines that remain static for the -filesystem. This element identifies entry points into the filesystem -to the generic code. - -@item mt_entry -This element identifies the mount table entry for this instance of the -filesystem. - -@end table - - - - - - - - |