1/*	$OpenBSD: pwcache.c,v 1.9 2005/08/08 08:05:34 espie Exp $ */
2/*
3 * Copyright (c) 1989, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 *    may be used to endorse or promote products derived from this software
16 *    without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31/* OPENBSD ORIGINAL: lib/libc/gen/pwcache.c */
32
33#include "includes.h"
34
35#include <sys/types.h>
36
37#include <grp.h>
38#include <pwd.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <string.h>
42
43#define	NCACHE	64			/* power of 2 */
44#define	MASK	(NCACHE - 1)		/* bits to store with */
45
46#ifndef HAVE_USER_FROM_UID
47char *
48user_from_uid(uid_t uid, int nouser)
49{
50	static struct ncache {
51		uid_t	uid;
52		char	*name;
53	} c_uid[NCACHE];
54	static int pwopen;
55	static char nbuf[15];		/* 32 bits == 10 digits */
56	struct passwd *pw;
57	struct ncache *cp;
58
59	cp = c_uid + (uid & MASK);
60	if (cp->uid != uid || cp->name == NULL) {
61		if (pwopen == 0) {
62#ifdef HAVE_SETPASSENT
63			setpassent(1);
64#endif
65			pwopen = 1;
66		}
67		if ((pw = getpwuid(uid)) == NULL) {
68			if (nouser)
69				return (NULL);
70			(void)snprintf(nbuf, sizeof(nbuf), "%u", uid);
71		}
72		cp->uid = uid;
73		if (cp->name != NULL)
74			free(cp->name);
75		cp->name = strdup(pw ? pw->pw_name : nbuf);
76	}
77	return (cp->name);
78}
79#endif
80
81#ifndef HAVE_GROUP_FROM_GID
82char *
83group_from_gid(gid_t gid, int nogroup)
84{
85	static struct ncache {
86		gid_t	gid;
87		char	*name;
88	} c_gid[NCACHE];
89	static int gropen;
90	static char nbuf[15];		/* 32 bits == 10 digits */
91	struct group *gr;
92	struct ncache *cp;
93
94	cp = c_gid + (gid & MASK);
95	if (cp->gid != gid || cp->name == NULL) {
96		if (gropen == 0) {
97#ifdef HAVE_SETGROUPENT
98			setgroupent(1);
99#endif
100			gropen = 1;
101		}
102		if ((gr = getgrgid(gid)) == NULL) {
103			if (nogroup)
104				return (NULL);
105			(void)snprintf(nbuf, sizeof(nbuf), "%u", gid);
106		}
107		cp->gid = gid;
108		if (cp->name != NULL)
109			free(cp->name);
110		cp->name = strdup(gr ? gr->gr_name : nbuf);
111	}
112	return (cp->name);
113}
114#endif
115