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 * @(#)pwcache.c 8.1 (Berkeley) 6/4/93 34 * $DragonFly: src/lib/libc/gen/pwcache.c,v 1.3 2004/06/06 15:05:55 hmp Exp $ 35 */ 36 37 #include <sys/types.h> 38 39 #include <grp.h> 40 #include <string.h> 41 #include <pwd.h> 42 #include <stdio.h> 43 #include <utmp.h> 44 45 #define NCACHE 64 /* power of 2 */ 46 #define MASK (NCACHE - 1) /* bits to store with */ 47 48 char * 49 user_from_uid(uid, nouser) 50 uid_t uid; 51 int nouser; 52 { 53 static struct ncache { 54 uid_t uid; 55 int found; 56 char name[UT_NAMESIZE + 1]; 57 } c_uid[NCACHE]; 58 static int pwopen; 59 struct passwd *pw; 60 struct ncache *cp; 61 62 cp = c_uid + (uid & MASK); 63 if (cp->uid != uid || !*cp->name) { 64 if (pwopen == 0) { 65 setpassent(1); 66 pwopen = 1; 67 } 68 pw = getpwuid(uid); 69 cp->uid = uid; 70 if (pw != NULL) { 71 cp->found = 1; 72 (void)strncpy(cp->name, pw->pw_name, UT_NAMESIZE); 73 cp->name[UT_NAMESIZE] = '\0'; 74 } else { 75 cp->found = 0; 76 (void)snprintf(cp->name, UT_NAMESIZE, "%u", uid); 77 if (nouser) 78 return (NULL); 79 } 80 } 81 return ((nouser && !cp->found) ? NULL : cp->name); 82 } 83 84 char * 85 group_from_gid(gid, nogroup) 86 gid_t gid; 87 int nogroup; 88 { 89 static struct ncache { 90 gid_t gid; 91 int found; 92 char name[UT_NAMESIZE + 1]; 93 } c_gid[NCACHE]; 94 static int gropen; 95 struct group *gr; 96 struct ncache *cp; 97 98 cp = c_gid + (gid & MASK); 99 if (cp->gid != gid || !*cp->name) { 100 if (gropen == 0) { 101 setgroupent(1); 102 gropen = 1; 103 } 104 gr = getgrgid(gid); 105 cp->gid = gid; 106 if (gr != NULL) { 107 cp->found = 1; 108 (void)strncpy(cp->name, gr->gr_name, UT_NAMESIZE); 109 cp->name[UT_NAMESIZE] = '\0'; 110 } else { 111 cp->found = 0; 112 (void)snprintf(cp->name, UT_NAMESIZE, "%u", gid); 113 if (nogroup) 114 return (NULL); 115 } 116 } 117 return ((nogroup && !cp->found) ? NULL : cp->name); 118 } 119