/**
* @file
*
* @brief IMFS Create a New Link Node
* @ingroup IMFS
*/
/*
* COPYRIGHT (c) 1989-2010.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include "imfs.h"
static const IMFS_node_control IMFS_node_control_hard_link;
int IMFS_link(
const rtems_filesystem_location_info_t *parentloc,
const rtems_filesystem_location_info_t *targetloc,
const char *name,
size_t namelen
)
{
IMFS_jnode_t *new_node;
IMFS_jnode_t *target;
target = targetloc->node_access;
/*
* Verify this node can be linked to.
*/
if ( target->st_nlink >= LINK_MAX )
rtems_set_errno_and_return_minus_one( EMLINK );
/*
* Create a new link node.
*/
new_node = IMFS_create_node(
parentloc,
&IMFS_node_control_hard_link,
sizeof( IMFS_link_t ),
name,
namelen,
IMFS_STAT_FMT_HARD_LINK | ( S_IRWXU | S_IRWXG | S_IRWXO ),
target
);
if ( !new_node )
rtems_set_errno_and_return_minus_one( ENOMEM );
/*
* Increment the link count of the node being pointed to.
*/
target->reference_count++;
target->st_nlink++;
IMFS_update_ctime( target );
return 0;
}
static int IMFS_stat_hard_link(
const rtems_filesystem_location_info_t *loc,
struct stat *buf
)
{
const IMFS_link_t *hard_link = loc->node_access;
rtems_filesystem_location_info_t targetloc = *loc;
targetloc.node_access = hard_link->link_node;
IMFS_Set_handlers( &targetloc );
return (targetloc.handlers->fstat_h)( &targetloc, buf );
}
static const rtems_filesystem_file_handlers_r IMFS_link_handlers = {
.open_h = rtems_filesystem_default_open,
.close_h = rtems_filesystem_default_close,
.read_h = rtems_filesystem_default_read,
.write_h = rtems_filesystem_default_write,
.ioctl_h = rtems_filesystem_default_ioctl,
.lseek_h = rtems_filesystem_default_lseek,
.fstat_h = IMFS_stat_hard_link,
.ftruncate_h = rtems_filesystem_default_ftruncate,
.fsync_h = rtems_filesystem_default_fsync_or_fdatasync,
.fdatasync_h = rtems_filesystem_default_fsync_or_fdatasync,
.fcntl_h = rtems_filesystem_default_fcntl,
.kqfilter_h = rtems_filesystem_default_kqfilter,
.mmap_h = rtems_filesystem_default_mmap,
.poll_h = rtems_filesystem_default_poll,
.readv_h = rtems_filesystem_default_readv,
.writev_h = rtems_filesystem_default_writev
};
static IMFS_jnode_t *IMFS_node_initialize_hard_link(
IMFS_jnode_t *node,
void *arg
)
{
IMFS_link_t *hard_link = (IMFS_link_t *) node;
hard_link->link_node = arg;
return node;
}
static IMFS_jnode_t *IMFS_node_remove_hard_link(
IMFS_jnode_t *node
)
{
IMFS_link_t *hard_link = (IMFS_link_t *) node;
IMFS_jnode_t *target = hard_link->link_node;
_Assert( target != NULL );
if ( target->st_nlink == 1 ) {
target = (*target->control->node_remove)( target );
if ( target == NULL ) {
node = NULL;
}
} else {
--target->st_nlink;
IMFS_update_ctime( target );
}
if ( target != NULL ) {
--target->reference_count;
if ( target->reference_count == 0 ) {
IMFS_node_destroy( target );
}
}
return node;
}
static const IMFS_node_control IMFS_node_control_hard_link = {
.handlers = &IMFS_link_handlers,
.node_initialize = IMFS_node_initialize_hard_link,
.node_remove = IMFS_node_remove_hard_link,
.node_destroy = IMFS_node_destroy_default
};