1/*
2 * Copyright (c) 1983, 1993
3 *	The Regents of the University of California.  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 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if defined(LIBC_SCCS) && !defined(lint)
31static char sccsid[] = "@(#)scandir.c	8.3 (Berkeley) 1/2/94";
32#endif /* LIBC_SCCS and not lint */
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD$");
35
36/*
37 * Scan the directory dirname calling select to make a list of selected
38 * directory entries then sort using qsort and compare routine dcomp.
39 * Returns the number of entries and a pointer to a list of pointers to
40 * struct dirent (through namelist). Returns -1 if there were any errors.
41 */
42
43#include "namespace.h"
44#include <dirent.h>
45#include <stdlib.h>
46#include <string.h>
47#include "un-namespace.h"
48
49static int alphasort_thunk(void *thunk, const void *p1, const void *p2);
50
51/*
52 * The DIRSIZ macro is the minimum record length which will hold the directory
53 * entry.  This requires the amount of space in struct dirent without the
54 * d_name field, plus enough space for the name and a terminating nul byte
55 * (dp->d_namlen + 1), rounded up to a 4 byte boundary.
56 */
57#undef DIRSIZ
58#define DIRSIZ(dp)							\
59	((sizeof(struct dirent) - sizeof(dp)->d_name) +			\
60	    (((dp)->d_namlen + 1 + 3) &~ 3))
61
62int
63scandir(const char *dirname, struct dirent ***namelist,
64    int (*select)(const struct dirent *), int (*dcomp)(const struct dirent **,
65	const struct dirent **))
66{
67	struct dirent *d, *p, **names = NULL;
68	size_t nitems = 0;
69	long arraysz;
70	DIR *dirp;
71
72	if ((dirp = opendir(dirname)) == NULL)
73		return(-1);
74
75	arraysz = 32;	/* initial estimate of the array size */
76	names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *));
77	if (names == NULL)
78		goto fail;
79
80	while ((d = readdir(dirp)) != NULL) {
81		if (select != NULL && !(*select)(d))
82			continue;	/* just selected names */
83		/*
84		 * Make a minimum size copy of the data
85		 */
86		p = (struct dirent *)malloc(DIRSIZ(d));
87		if (p == NULL)
88			goto fail;
89		p->d_fileno = d->d_fileno;
90		p->d_type = d->d_type;
91		p->d_reclen = d->d_reclen;
92		p->d_namlen = d->d_namlen;
93		bcopy(d->d_name, p->d_name, p->d_namlen + 1);
94		/*
95		 * Check to make sure the array has space left and
96		 * realloc the maximum size.
97		 */
98		if (nitems >= arraysz) {
99			struct dirent **names2;
100
101			names2 = (struct dirent **)realloc((char *)names,
102				(arraysz * 2) * sizeof(struct dirent *));
103			if (names2 == NULL) {
104				free(p);
105				goto fail;
106			}
107			names = names2;
108			arraysz *= 2;
109		}
110		names[nitems++] = p;
111	}
112	closedir(dirp);
113	if (nitems && dcomp != NULL)
114		qsort_r(names, nitems, sizeof(struct dirent *),
115		    &dcomp, alphasort_thunk);
116	*namelist = names;
117	return (nitems);
118
119fail:
120	while (nitems > 0)
121		free(names[--nitems]);
122	free(names);
123	closedir(dirp);
124	return (-1);
125}
126
127/*
128 * Alphabetic order comparison routine for those who want it.
129 * POSIX 2008 requires that alphasort() uses strcoll().
130 */
131int
132alphasort(const struct dirent **d1, const struct dirent **d2)
133{
134
135	return (strcoll((*d1)->d_name, (*d2)->d_name));
136}
137
138static int
139alphasort_thunk(void *thunk, const void *p1, const void *p2)
140{
141	int (*dc)(const struct dirent **, const struct dirent **);
142
143	dc = *(int (**)(const struct dirent **, const struct dirent **))thunk;
144	return (dc((const struct dirent **)p1, (const struct dirent **)p2));
145}
146