util.subproj/pwcache.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
  26  *
  27  * Copyright (c) 1989, 1993
  28  *      The Regents of the University of California.  All rights reserved.
  29  *
  30  * The NEXTSTEP Software License Agreement specifies the terms
  31  * and conditions for redistribution.
  32  *
  33  *      @(#)pwcache.c   8.1 (Berkeley) 6/4/93
  34  */
  35
  36
  37 #include <sys/types.h>
  38
  39 #include <grp.h>
  40 #include <pwd.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.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                 char    name[UT_NAMESIZE + 1];
  57         } *c_uid[NCACHE];
  58         static int pwopen;
  59         static char nbuf[15];           /* 32 bits == 10 digits */
  60         register struct passwd *pw;
  61         register struct ncache **cp;
  62
  63         cp = &c_uid[uid & MASK];
  64         if (*cp == NULL || (*cp)->uid != uid || !*(*cp)->name) {
  65                 if (pwopen == 0) {
  66                         setpassent(1);
  67                         pwopen = 1;
  68                 }
  69                 if ((pw = getpwuid(uid)) == NULL) {
  70 err:
  71                         if (nouser)
  72                                 return (NULL);
  73                         (void)snprintf(nbuf, sizeof(nbuf), "%u", uid);
  74                         return (nbuf);
  75                 }
  76                 if (*cp == NULL) {
  77                         *cp = malloc(sizeof(struct ncache));
  78                         if (*cp == NULL)
  79                                 goto err;
  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 = NULL;
 101
 102         cp = &c_gid[gid & MASK];
 103         if (*cp == NULL || (*cp)->gid != gid || !*(*cp)->name) {
 104                 if (gropen == 0) {
 105                         setgroupent(1);
 106                         gropen = 1;
 107                 }
 108                 if ((gr = getgrgid(gid)) == NULL) {
 109 err:
 110                         if (nogroup)
 111                                 return (NULL);
 112                         (void)snprintf(nbuf, sizeof(nbuf), "%u", gid);
 113                         return (nbuf);
 114                 }
 115                 if (*cp == NULL) {
 116                         *cp = malloc(sizeof(struct ncache));
 117                         if (*cp == NULL)
 118                                 goto err;
 119                 }
 120                 (*cp)->gid = gid;
 121                 (void)strncpy((*cp)->name, gr->gr_name, UT_NAMESIZE);
 122                 (*cp)->name[UT_NAMESIZE] = '\0';
 123         }
 124         return ((*cp)->name);
 125 }