usr/src/lib/libast/common/string/fmtgid.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23 /*
  24  * Glenn Fowler
  25  * AT&T Bell Laboratories
  26  *
  27  * cached gid number -> name
  28  */
  29
  30 #if defined(__STDPP__directive) && defined(__STDPP__hide)
  31 __STDPP__directive pragma pp:hide getgrgid
  32 #else
  33 #define getgrgid        ______getgrgid
  34 #endif
  35
  36 #include <ast.h>
  37 #include <cdt.h>
  38 #include <grp.h>
  39
  40 #if defined(__STDPP__directive) && defined(__STDPP__hide)
  41 __STDPP__directive pragma pp:nohide getgrgid
  42 #else
  43 #undef  getgrgid
  44 #endif
  45
  46 extern struct group*    getgrgid(gid_t);
  47
  48 typedef struct Id_s
  49 {
  50         Dtlink_t        link;
  51         int             id;
  52         char            name[1];
  53 } Id_t;
  54
  55 /*
  56  * return gid name given gid number
  57  */
  58
  59 char*
  60 fmtgid(int gid)
  61 {
  62         register Id_t*          ip;
  63         register char*          name;
  64         register struct group*  gr;
  65         int                     z;
  66
  67         static Dt_t*            dict;
  68         static Dtdisc_t         disc;
  69
  70         if (!dict)
  71         {
  72                 disc.key = offsetof(Id_t, id);
  73                 disc.size = sizeof(int);
  74                 dict = dtopen(&disc, Dthash);
  75         }
  76         else if (ip = (Id_t*)dtmatch(dict, &gid))
  77                 return ip->name;
  78         if (gr = getgrgid(gid))
  79         {
  80                 name = gr->gr_name;
  81 #if _WINIX
  82                 if (streq(name, "Administrators"))
  83                         name = "sys";
  84 #endif
  85         }
  86         else if (gid == 0)
  87                 name = "sys";
  88         else
  89         {
  90                 name = fmtbuf(z = sizeof(gid) * 3 + 1);
  91                 sfsprintf(name, z, "%I*d", sizeof(gid), gid);
  92         }
  93         if (dict && (ip = newof(0, Id_t, 1, strlen(name))))
  94         {
  95                 ip->id = gid;
  96                 strcpy(ip->name, name);
  97                 dtinsert(dict, ip);
  98                 return ip->name;
  99         }
 100         return name;
 101 }