xref: /titanic_51/usr/src/lib/libbc/libc/gen/common/readdir.c (revision b3697b90e692e3e5d859fb77d285d4c056d99eda)
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 }
68