source: rtems/c/src/exec/libfs/src/imfs/deviceio.c @ b568ccb

/*
 *  IMFS Device Node Handlers
 *
 *  This file contains the set of handlers used to map operations on
 *  IMFS device nodes onto calls to the RTEMS Classic API IO Manager.
 *
 *  COPYRIGHT (c) 1989-1998.
 *  On-Line Applications Research Corporation (OAR).
 *  Copyright assigned to U.S. Government, 1994.
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.OARcorp.com/rtems/license.html.
 *
 *  $Id$
 */

#include <rtems.h>
#include <rtems/libio.h>
#include "libio_.h"

#include "imfs.h"

/*
 *  device_open
 *
 *  This handler maps an open() operation onto rtems_io_open().
 */

int device_open(
  rtems_libio_t *iop,
  const char    *pathname,
  unsigned32     flag,
  unsigned32     mode
)
{
  rtems_libio_open_close_args_t  args;
  rtems_status_code              status;
  IMFS_jnode_t                  *the_jnode;

  the_jnode  = iop->file_info;

  args.iop   = iop;
  args.flags = iop->flags;
  args.mode  = mode;

  status = rtems_io_open(
    the_jnode->info.device.major,
    the_jnode->info.device.minor,
    (void *) &args
  );
  if ( status )
    return RTEMS_UNSATISFIED;

  return 0;
}

/*
 *  device_close
 *
 *  This handler maps a close() operation onto rtems_io_close().
 */

int device_close(
  rtems_libio_t *iop
)
{
  rtems_libio_open_close_args_t  args;
  rtems_status_code              status;
  IMFS_jnode_t                  *the_jnode;

  the_jnode = iop->file_info;

  args.iop   = iop;
  args.flags = 0;
  args.mode  = 0;

  status = rtems_io_close(
    the_jnode->info.device.major,
    the_jnode->info.device.minor,
    (void *) &args
  );
  if ( status )
    return RTEMS_UNSATISFIED;

  return 0;
}

/*
 *  device_read
 *
 *  This handler maps a read() operation onto rtems_io_read().
 */

int device_read(
  rtems_libio_t *iop,
  void          *buffer,
  unsigned32     count
)
{
  rtems_libio_rw_args_t   args;
  rtems_status_code       status;
  IMFS_jnode_t           *the_jnode;

  the_jnode = iop->file_info;

  args.iop         = iop;
  args.offset      = iop->offset;
  args.buffer      = buffer;
  args.count       = count;
  args.flags       = iop->flags;
  args.bytes_moved = 0;

  status = rtems_io_read(
    the_jnode->info.device.major,
    the_jnode->info.device.minor,
    (void *) &args
  );

  if ( status )
    return -1;

  return args.bytes_moved;
}

/*
 *  device_write
 *
 *  This handler maps a write() operation onto rtems_io_write().
 */

int device_write(
  rtems_libio_t *iop,
  const void    *buffer,
  unsigned32     count
)
{
  rtems_libio_rw_args_t   args;
  rtems_status_code       status;
  IMFS_jnode_t           *the_jnode;

  the_jnode = iop->file_info;

  args.iop         = iop;
  args.offset      = iop->offset;
  args.buffer      = (void *) buffer;
  args.count       = count;
  args.flags       = iop->flags;
  args.bytes_moved = 0;

  status = rtems_io_write(
    the_jnode->info.device.major,
    the_jnode->info.device.minor,
    (void *) &args
  );

  if ( status )
    return -1;

  return args.bytes_moved;
}

/*
 *  device_ioctl
 *
 *  This handler maps an ioctl() operation onto rtems_io_ioctl().
 */

int device_ioctl(
  rtems_libio_t *iop,
  unsigned32     command,
  void          *buffer
)
{
  rtems_libio_ioctl_args_t  args;
  rtems_status_code         status;
  IMFS_jnode_t             *the_jnode;

  args.iop     = iop;
  args.command = command;
  args.buffer  = buffer;

  the_jnode = iop->file_info;

  status = rtems_io_control(
    the_jnode->info.device.major,
    the_jnode->info.device.minor,
    (void *) &args
  );

  if ( status )
    return -1;

  return args.ioctl_return;
}

/*
 *  device_lseek
 *
 *  This handler eats all lseek() operations.
 */

int device_lseek(
  rtems_libio_t *iop,
  off_t          offset,
  int            whence
)
{
  return 0;
}

/*
 *  device_stat
 *
 *  This IMFS_stat() is used.
 */

/*
 *  device_rmnod
 */

int device_rmnod(
  rtems_filesystem_location_info_t      *pathloc       /* IN */
)
{
  IMFS_jnode_t *the_jnode;  

  the_jnode = (IMFS_jnode_t *) pathloc->node_access;

  /* 
   * Take the node out of the parent's chain that contains this node 
   */

  if ( the_jnode->Parent != NULL ) {
    Chain_Extract( (Chain_Node *) the_jnode );
    the_jnode->Parent = NULL;
  }

  /*
   * Decrement the link counter and see if we can free the space.
   */

  the_jnode->st_nlink--;
  IMFS_update_ctime( the_jnode );

  /*
   * The file cannot be open and the link must be less than 1 to free.
   */

  if ( !rtems_libio_is_file_open( the_jnode ) && (the_jnode->st_nlink < 1) ) {

    /* 
     * Is the rtems_filesystem_current is this node?
     */

    if ( rtems_filesystem_current.node_access == pathloc->node_access )
       rtems_filesystem_current.node_access = NULL;

    /*
     * Free memory associated with a memory file.
     */

    free( the_jnode );
  }

  return 0;

}