libcsupport/src/getdents.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  *  @file
0005  *
0006  *  @brief Get Directory Entries
0007  *  @ingroup libcsupport
0008  */
0009
0010 /*
0011  *  COPYRIGHT (c) 1989-2013.
0012  *  On-Line Applications Research Corporation (OAR).
0013  *
0014  * Redistribution and use in source and binary forms, with or without
0015  * modification, are permitted provided that the following conditions
0016  * are met:
0017  * 1. Redistributions of source code must retain the above copyright
0018  *    notice, this list of conditions and the following disclaimer.
0019  * 2. Redistributions in binary form must reproduce the above copyright
0020  *    notice, this list of conditions and the following disclaimer in the
0021  *    documentation and/or other materials provided with the distribution.
0022  *
0023  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0024  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0025  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0026  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0027  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0028  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0029  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0030  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0031  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0032  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0033  * POSSIBILITY OF SUCH DAMAGE.
0034  */
0035
0036 #ifdef HAVE_CONFIG_H
0037 #include "config.h"
0038 #endif
0039
0040 #include <errno.h>
0041
0042 #include <rtems/score/objectimpl.h>
0043 #include <rtems/libio_.h>
0044 #include <rtems/seterr.h>
0045
0046 /*
0047  *  Prototypes to avoid warnings
0048  */
0049 int getdents(
0050   int   dd_fd,
0051   char *dd_buf,
0052   int   dd_len
0053 );
0054
0055 /**
0056  *  SVR4 and SVID extension required by Newlib readdir() family.
0057  *
0058  *  This routine will dd_len / (sizeof dirent) directory entries relative to
0059  *  the current directory position index. These entries will be placed in
0060  *  character array pointed to by -dd_buf-
0061  */
0062 int getdents(
0063   int   dd_fd,
0064   char *dd_buf,
0065   int   dd_len
0066 )
0067 {
0068   rtems_libio_t *iop;
0069   mode_t type;
0070   int result;
0071
0072   /*
0073    *  Get the file control block structure associated with the file descriptor
0074    */
0075   LIBIO_GET_IOP_WITH_ACCESS( dd_fd, iop, LIBIO_FLAGS_READ, EBADF );
0076
0077   /*
0078    *  Make sure we are working on a directory
0079    */
0080   type = rtems_filesystem_location_type( &iop->pathinfo );
0081   if ( !S_ISDIR( type ) ) {
0082     rtems_libio_iop_drop( iop );
0083     rtems_set_errno_and_return_minus_one( ENOTDIR );
0084   }
0085
0086   /*
0087    *  Return the number of bytes that were actually transfered as a result
0088    *  of the read attempt.
0089    */
0090   result = (*iop->pathinfo.handlers->read_h)( iop, dd_buf, dd_len  );
0091   rtems_libio_iop_drop( iop );
0092   return result;
0093 }