1 /*
2  * Copyright (c) 1983 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 /* Modified from newlib/libc/posix/readdir.c */
35 
36 #include <dirent.h>
37 #include <machine/syscall.h>
38 
39 #define __NR___getdents64 __NR_getdents64
40 
41 static _syscall3(int,__getdents64,int,fd,struct dirent64 *,dirp,unsigned int,count)
42 
43 /*
44  * get next entry in a directory.
45  */
46 struct dirent64 *
47 __readdir64 (dirp)
48 register DIR *dirp; {
49   register struct dirent64 *dp;
50 
51 #ifdef HAVE_DD_LOCK
52   __lock_acquire_recursive(dirp->dd_lock);
53 #endif
54 
55   if (dirp->dd_fd == -1)
56     return NULL;
57 
58   for (;;) {
59     if (dirp->dd_loc == 0) {
60       dirp->dd_size = __getdents64 (dirp->dd_fd,
61 				    (void *)dirp->dd_buf,
62 				    dirp->dd_len);
63 
64       if (dirp->dd_size <= 0) {
65 #ifdef HAVE_DD_LOCK
66         __lock_release_recursive(dirp->dd_lock);
67 #endif
68 	return NULL;
69       }
70     }
71     if (dirp->dd_loc >= dirp->dd_size) {
72       dirp->dd_loc = 0;
73       continue;
74     }
75     dp = (struct dirent64 *)(dirp->dd_buf + dirp->dd_loc);
76     if ((int)dp & 03) {	/* bogus pointer check */
77 #ifdef HAVE_DD_LOCK
78       __lock_release_recursive(dirp->dd_lock);
79 #endif
80       return NULL;
81     }
82     if (dp->d_reclen <= 0 ||
83 	dp->d_reclen > dirp->dd_len + 1 - dirp->dd_loc) {
84 #ifdef HAVE_DD_LOCK
85       __lock_release_recursive(dirp->dd_lock);
86 #endif
87       return NULL;
88     }
89     dirp->dd_loc += dp->d_reclen;
90     if (dp->d_ino == 0)
91       continue;
92 #ifdef HAVE_DD_LOCK
93     __lock_release_recursive(dirp->dd_lock);
94 #endif
95     return (dp);
96   }
97 }
98