1 /* 2 * Copyright (c) 1989, 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 * 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 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)pwcache.c 8.1 (Berkeley) 6/4/93"; 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include <sys/types.h> 39 40 #include <grp.h> 41 #include <string.h> 42 #include <pwd.h> 43 #include <stdio.h> 44 #include <utmp.h> 45 46 #define NCACHE 64 /* power of 2 */ 47 #define MASK (NCACHE - 1) /* bits to store with */ 48 49 char * 50 user_from_uid(uid, nouser) 51 uid_t uid; 52 int nouser; 53 { 54 static struct ncache { 55 uid_t uid; 56 int found; 57 char name[UT_NAMESIZE + 1]; 58 } c_uid[NCACHE]; 59 static int pwopen; 60 register struct passwd *pw; 61 register struct ncache *cp; 62 63 cp = c_uid + (uid & MASK); 64 if (cp->uid != uid || !*cp->name) { 65 if (pwopen == 0) { 66 setpassent(1); 67 pwopen = 1; 68 } 69 pw = getpwuid(uid); 70 cp->uid = uid; 71 if (pw != NULL) { 72 cp->found = 1; 73 (void)strncpy(cp->name, pw->pw_name, UT_NAMESIZE); 74 cp->name[UT_NAMESIZE] = '\0'; 75 } else { 76 cp->found = 0; 77 (void)snprintf(cp->name, UT_NAMESIZE, "%u", uid); 78 if (nouser) 79 return (NULL); 80 } 81 } 82 return ((nouser && !cp->found) ? NULL : cp->name); 83 } 84 85 char * 86 group_from_gid(gid, nogroup) 87 gid_t gid; 88 int nogroup; 89 { 90 static struct ncache { 91 gid_t gid; 92 int found; 93 char name[UT_NAMESIZE + 1]; 94 } c_gid[NCACHE]; 95 static int gropen; 96 struct group *gr; 97 struct ncache *cp; 98 99 cp = c_gid + (gid & MASK); 100 if (cp->gid != gid || !*cp->name) { 101 if (gropen == 0) { 102 setgroupent(1); 103 gropen = 1; 104 } 105 gr = getgrgid(gid); 106 cp->gid = gid; 107 if (gr != NULL) { 108 cp->found = 1; 109 (void)strncpy(cp->name, gr->gr_name, UT_NAMESIZE); 110 cp->name[UT_NAMESIZE] = '\0'; 111 } else { 112 cp->found = 0; 113 (void)snprintf(cp->name, UT_NAMESIZE, "%u", gid); 114 if (nogroup) 115 return (NULL); 116 } 117 } 118 return ((nogroup && !cp->found) ? NULL : cp->name); 119 } 120