usr/src/lib/libbc/libc/gen/common/readdir.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1987 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <sys/param.h>
  30 #include <dirent.h>
  31
  32 /*
  33  * get next entry in a directory.
  34  */
  35 struct dirent *
  36 readdir(dirp)
  37         register DIR *dirp;
  38 {
  39         register struct dirent *dp;
  40         int saveloc = 0;
  41
  42 next:
  43         if (dirp->dd_size != 0) {
  44                 dp = (struct dirent *)&dirp->dd_buf[dirp->dd_loc];
  45                 saveloc = dirp->dd_loc;   /* save for possible EOF */
  46                 dirp->dd_loc += dp->d_reclen;
  47         }
  48         if (dirp->dd_loc >= dirp->dd_size)
  49                 dirp->dd_loc = dirp->dd_size = 0;
  50
  51         if (dirp->dd_size == 0  /* refill buffer */
  52           && (dirp->dd_size = getdents(dirp->dd_fd, dirp->dd_buf, dirp->dd_bsize)
  53              ) <= 0
  54            ) {
  55                 if (dirp->dd_size == 0) /* This means EOF */
  56                         dirp->dd_loc = saveloc;  /* EOF so save for telldir */
  57                 return (NULL);    /* error or EOF */
  58         }
  59
  60         dp = (struct dirent *)&dirp->dd_buf[dirp->dd_loc];
  61         if (dp->d_reclen <= 0)
  62                 return (NULL);
  63         if (dp->d_fileno == 0)
  64                 goto next;
  65         dirp->dd_off = dp->d_off;
  66         return(dp);
  67 }