xref: /illumos-gate/usr/src/contrib/ast/src/lib/libast/string/fmtgid.c (revision b30d193948be5a7794d7ae3ba0ed9c2f72c88e0f)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                 Eclipse Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *          http://www.eclipse.org/org/documents/epl-v10.html           *
11 *         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
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*
fmtgid(int gid)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, Dtset);
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 }
102