1 /* $NetBSD: pwcache.c,v 1.5 1995/05/13 06:58:23 jtc Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)pwcache.c 8.1 (Berkeley) 6/4/93"; 39 #else 40 static char rcsid[] = "$NetBSD: pwcache.c,v 1.5 1995/05/13 06:58:23 jtc Exp $"; 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include <sys/types.h> 45 46 #include <grp.h> 47 #include <pwd.h> 48 #include <stdio.h> 49 #include <string.h> 50 #include <utmp.h> 51 52 #define NCACHE 64 /* power of 2 */ 53 #define MASK NCACHE - 1 /* bits to store with */ 54 55 char * 56 user_from_uid(uid, nouser) 57 uid_t uid; 58 int nouser; 59 { 60 static struct ncache { 61 uid_t uid; 62 char name[UT_NAMESIZE + 1]; 63 } c_uid[NCACHE]; 64 static int pwopen; 65 static char nbuf[15]; /* 32 bits == 10 digits */ 66 register struct passwd *pw; 67 register struct ncache *cp; 68 69 cp = c_uid + (uid & MASK); 70 if (cp->uid != uid || !*cp->name) { 71 if (pwopen == 0) { 72 setpassent(1); 73 pwopen = 1; 74 } 75 if ((pw = getpwuid(uid)) == NULL) { 76 if (nouser) 77 return (NULL); 78 (void)snprintf(nbuf, sizeof(nbuf), "%u", uid); 79 return (nbuf); 80 } 81 cp->uid = uid; 82 (void)strncpy(cp->name, pw->pw_name, UT_NAMESIZE); 83 cp->name[UT_NAMESIZE] = '\0'; 84 } 85 return (cp->name); 86 } 87 88 char * 89 group_from_gid(gid, nogroup) 90 gid_t gid; 91 int nogroup; 92 { 93 static struct ncache { 94 gid_t gid; 95 char name[UT_NAMESIZE + 1]; 96 } c_gid[NCACHE]; 97 static int gropen; 98 static char nbuf[15]; /* 32 bits == 10 digits */ 99 struct group *gr; 100 struct ncache *cp; 101 102 cp = c_gid + (gid & MASK); 103 if (cp->gid != gid || !*cp->name) { 104 if (gropen == 0) { 105 setgroupent(1); 106 gropen = 1; 107 } 108 if ((gr = getgrgid(gid)) == NULL) { 109 if (nogroup) 110 return (NULL); 111 (void)snprintf(nbuf, sizeof(nbuf), "%u", gid); 112 return (nbuf); 113 } 114 cp->gid = gid; 115 (void)strncpy(cp->name, gr->gr_name, UT_NAMESIZE); 116 cp->name[UT_NAMESIZE] = '\0'; 117 } 118 return (cp->name); 119 } 120