source: rtems/c/src/lib/libc/readdir.c @ 69537ca9

4.104.114.84.95
Last change on this file since 69537ca9 was 19b74f31, checked in by Joel Sherrill <joel.sherrill@…>, on 11/02/99 at 16:25:05

Check for NULL being passed in.

  • Property mode set to 100644
File size: 2.8 KB
Line 
1/*
2 *  readdir() - POSIX 1003.1b - XXX
3 *
4 *  This was copied from Newlib 1.8.0.
5 *
6 * 
7 * Copyright (c) 1983 Regents of the University of California.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *      This product includes software developed by the University of
21 *      California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39#if defined(LIBC_SCCS) && !defined(lint)
40static char sccsid[] = "@(#)readdir.c   5.7 (Berkeley) 6/1/90";
41#endif /* LIBC_SCCS and not lint */
42
43#include <dirent.h>
44
45int getdents(
46  int dd_fd,
47  char *dd_buf,
48  int dd_len
49);
50
51/*
52 * get next entry in a directory.
53 */
54struct dirent *
55readdir(dirp)
56register DIR *dirp; {
57  register struct dirent *dp;
58 
59  if ( !dirp )
60    return NULL;
61
62  for (;;) {
63    if (dirp->dd_loc == 0) {
64      dirp->dd_size = getdents (dirp->dd_fd,
65                                dirp->dd_buf,
66                                dirp->dd_len);
67     
68      if (dirp->dd_size <= 0)
69        return NULL;
70    }
71    if (dirp->dd_loc >= dirp->dd_size) {
72      dirp->dd_loc = 0;
73      continue;
74    }
75    dp = (struct dirent *)(dirp->dd_buf + dirp->dd_loc);
76    if ((int)dp & 03)   /* bogus pointer check */
77      return NULL;
78    if (dp->d_reclen <= 0 ||
79        dp->d_reclen > dirp->dd_len + 1 - dirp->dd_loc)
80      return NULL;
81    dirp->dd_loc += dp->d_reclen;
82    if (dp->d_ino == 0)
83      continue;
84    return (dp);
85  }
86}
Note: See TracBrowser for help on using the repository browser.