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/*

 *  This file contains the support infrastructure used to manage the

 *  table of integer style file descriptors used by the low level

 *  POSIX system calls like open(), read, fstat(), etc.

 *

 *  COPYRIGHT (c) 1989-1999.

 *  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.OARcorp.com/rtems/license.html.

 *

 *  $Id: libio.c,v 1.2 2001-09-27 12:01:15 chris Exp $

 */

#include "libio_.h"                   /* libio_.h pulls in rtems */

#include <rtems.h>

#include <rtems/assoc.h>                /* assoc.h not included by rtems.h */

#include <stdio.h>                      /* O_RDONLY, et.al. */

#include <fcntl.h>                      /* O_RDONLY, et.al. */

#include <assert.h>

#include <errno.h>

#if ! defined(O_NDELAY)

# if defined(solaris2)

#  define O_NDELAY O_NONBLOCK

# elif defined(RTEMS_NEWLIB)

#  define O_NDELAY _FNBIO

# endif

#endif

#include <errno.h>

#include <string.h>                     /* strcmp */

#include <unistd.h>

#include <stdlib.h>                     /* calloc() */

#include <rtems/libio.h>                /* libio.h not pulled in by rtems */

/*

 *  File descriptor Table Information

 */

extern unsigned32  rtems_libio_number_iops;

rtems_id           rtems_libio_semaphore;

rtems_libio_t     *rtems_libio_iops;

rtems_libio_t     *rtems_libio_iop_freelist;

/*

 *  rtems_libio_init

 *

 *  Called by BSP startup code to initialize the libio subsystem.

 */

void rtems_libio_init( void )

{

    rtems_status_code rc;

    int i;

    rtems_libio_t *iop;

    if (rtems_libio_number_iops > 0)

    {

        rtems_libio_iops = (rtems_libio_t *) calloc(rtems_libio_number_iops,

                                                    sizeof(rtems_libio_t));

        if (rtems_libio_iops == NULL)

            rtems_fatal_error_occurred(RTEMS_NO_MEMORY);

        iop = rtems_libio_iop_freelist = rtems_libio_iops;

        for (i = 0 ; i < (rtems_libio_number_iops - 1) ; i++, iop++)

                iop->data1 = iop + 1;

        iop->data1 = NULL;

    }

  /*

   *  Create the binary semaphore used to provide mutual exclusion

   *  on the IOP Table.

   */

  rc = rtems_semaphore_create(

    RTEMS_LIBIO_SEM,

    1,

    RTEMS_BINARY_SEMAPHORE | RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY,

    RTEMS_NO_PRIORITY,

    &rtems_libio_semaphore

  );

  if ( rc != RTEMS_SUCCESSFUL )

    rtems_fatal_error_occurred( rc );

  /*

   *  Initialize the base file system infrastructure.

   */

  rtems_filesystem_initialize();

}

/*

 *  rtems_libio_fcntl_flags

 *

 *  Convert UNIX fnctl(2) flags to ones that RTEMS drivers understand

 */

rtems_assoc_t access_modes_assoc[] = {

  { "READ",       LIBIO_FLAGS_READ,  O_RDONLY },

  { "WRITE",      LIBIO_FLAGS_WRITE, O_WRONLY },

  { "READ/WRITE", LIBIO_FLAGS_READ_WRITE, O_RDWR },

  { 0, 0, 0 },

};

rtems_assoc_t status_flags_assoc[] = {

  { "NO DELAY",  LIBIO_FLAGS_NO_DELAY,  O_NDELAY },

  { "APPEND",    LIBIO_FLAGS_APPEND,    O_APPEND },

  { "CREATE",    LIBIO_FLAGS_CREATE,    O_CREAT },

  { 0, 0, 0 },

};

unsigned32 rtems_libio_fcntl_flags(

  unsigned32 fcntl_flags

)

{

  unsigned32 flags = 0;

  unsigned32 access_modes;

  /*

   * Access mode is a small integer

   */

  access_modes = fcntl_flags & O_ACCMODE;

  fcntl_flags &= ~O_ACCMODE;

  flags = rtems_assoc_local_by_remote( access_modes_assoc, access_modes );

  /*

   * Everything else is single bits

   */

  flags |=

     rtems_assoc_local_by_remote_bitfield(status_flags_assoc, fcntl_flags);

  return flags;

}

/*

 *  rtems_libio_to_fcntl_flags

 *

 *  Convert RTEMS internal flags to UNIX fnctl(2) flags

 */

unsigned32 rtems_libio_to_fcntl_flags(

  unsigned32 flags

)

{

  unsigned32 fcntl_flags = 0;

  if ( (flags & LIBIO_FLAGS_READ_WRITE) == LIBIO_FLAGS_READ_WRITE ) {

    fcntl_flags |= O_RDWR;

  } else if ( (flags & LIBIO_FLAGS_READ) == LIBIO_FLAGS_READ) {

    fcntl_flags |= O_RDONLY;

  } else if ( (flags & LIBIO_FLAGS_WRITE) == LIBIO_FLAGS_WRITE) {

    fcntl_flags |= O_WRONLY;

  }

  if ( (flags & LIBIO_FLAGS_NO_DELAY) == LIBIO_FLAGS_NO_DELAY ) {

    fcntl_flags |= O_NDELAY;

  }

  if ( (flags & LIBIO_FLAGS_APPEND) == LIBIO_FLAGS_APPEND ) {

    fcntl_flags |= O_APPEND;

  }

  if ( (flags & LIBIO_FLAGS_CREATE) == LIBIO_FLAGS_CREATE ) {

    fcntl_flags |= O_CREAT;

  }

  return fcntl_flags;

}

/*

 *  rtems_libio_allocate

 *

 *  This routine searches the IOP Table for an unused entry.  If it

 *  finds one, it returns it.  Otherwise, it returns NULL.

 */

rtems_libio_t *rtems_libio_allocate( void )

{

  rtems_libio_t *iop;

  rtems_status_code rc;

  rtems_semaphore_obtain( rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT );

  if (rtems_libio_iop_freelist) {

    iop = rtems_libio_iop_freelist;

    rc = rtems_semaphore_create(

      RTEMS_LIBIO_IOP_SEM(iop - rtems_libio_iops),

      1,

      RTEMS_BINARY_SEMAPHORE | RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY,

      RTEMS_NO_PRIORITY,

      &iop->sem

    );

    if (rc != RTEMS_SUCCESSFUL)

      goto failed;

    rtems_libio_iop_freelist = iop->data1;

    iop->data1 = 0;

    iop->flags = LIBIO_FLAGS_OPEN;

    goto done;

  }

failed:

  iop = 0;

done:

  rtems_semaphore_release( rtems_libio_semaphore );

  return iop;

}

/*

 *  rtems_libio_free

 *

 *  This routine frees the resources associated with an IOP (file descriptor)

 *  and clears the slot in the IOP Table.

 */

void rtems_libio_free(

  rtems_libio_t *iop

)

{

  rtems_semaphore_obtain( rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT );

    if (iop->sem)

      rtems_semaphore_delete(iop->sem);

    iop->flags &= ~LIBIO_FLAGS_OPEN;

    iop->data1 = rtems_libio_iop_freelist;

    rtems_libio_iop_freelist = iop;

  rtems_semaphore_release(rtems_libio_semaphore);

}

/*

 *  rtems_libio_is_open_files_in_fs

 *

 *  This routine scans the entire file descriptor table to determine if the

 *  are any active file descriptors that refer to the at least one node in the

 *  file system that we are trying to dismount.

 *

 *  If there is at least one node in the file system referenced by the mount

 *  table entry a 1 is returned, otherwise a 0 is returned.

 */

int rtems_libio_is_open_files_in_fs(

  rtems_filesystem_mount_table_entry_t * fs_mt_entry

)

{

  rtems_libio_t     *iop;

  int                result = 0;

  int                i;

  rtems_semaphore_obtain( rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT );

  /*

   *  Look for any active file descriptor entry.

   */

  for (iop=rtems_libio_iops,i=0; i < rtems_libio_number_iops; iop++, i++){

    if ((iop->flags & LIBIO_FLAGS_OPEN) != 0) {

       /*

        *  Check if this node is under the file system that we

        *  are trying to dismount.

        */

       if ( iop->pathinfo.mt_entry == fs_mt_entry ) {

          result = 1;

          break;

       }

    }

  }

  rtems_semaphore_release( rtems_libio_semaphore );

  return result;

}

/*

 *  rtems_libio_is_file_open

 *

 *  This routine scans the entire file descriptor table to determine if the

 *  given file refers to an active file descriptor.

 *

 *  If the given file is open a 1 is returned, otherwise a 0 is returned.

 */

int rtems_libio_is_file_open(

  void         *node_access

)

{

  rtems_libio_t     *iop;

  int                result=0;

  int                i;

  rtems_semaphore_obtain( rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT );

  /*

   *  Look for any active file descriptor entry.

   */

 for (iop=rtems_libio_iops,i=0; i < rtems_libio_number_iops; iop++, i++){

    if ((iop->flags & LIBIO_FLAGS_OPEN) != 0) {

       /*

        *  Check if this node is under the file system that we

        *  are trying to dismount.

        */

       if ( iop->pathinfo.node_access == node_access ) {

          result = 1;

          break;

       }

    }

  }

  rtems_semaphore_release( rtems_libio_semaphore );

  return result;

}