xref: /freebsd/lib/libc/gen/confstr.c (revision 87569f75a91f298c52a71823c04d41cf53c88889)
1 /*-
2  * Copyright (c) 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[] = "@(#)confstr.c	8.1 (Berkeley) 6/4/93";
36 #endif /* LIBC_SCCS and not lint */
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <sys/param.h>
41 
42 #include <errno.h>
43 #include <limits.h>
44 #include <paths.h>
45 #include <string.h>
46 #include <unistd.h>
47 
48 
49 size_t
50 confstr(int name, char *buf, size_t len)
51 {
52 	const char *p;
53 	const char UPE[] = "unsupported programming environment";
54 
55 	switch (name) {
56 	case _CS_PATH:
57 		p = _PATH_STDPATH;
58 		goto docopy;
59 
60 		/*
61 		 * POSIX/SUS ``Programming Environments'' stuff
62 		 *
63 		 * We don't support more than one programming environment
64 		 * on any platform (yet), so we just return the empty
65 		 * string for the environment we are compiled for,
66 		 * and the string "unsupported programming environment"
67 		 * for anything else.  (The Standard says that if these
68 		 * values are used on a system which does not support
69 		 * this environment -- determined via sysconf() -- then
70 		 * the value we return is unspecified.  So, we return
71 		 * something which will cause obvious breakage.)
72 		 */
73 	case _CS_POSIX_V6_ILP32_OFF32_CFLAGS:
74 	case _CS_POSIX_V6_ILP32_OFF32_LDFLAGS:
75 	case _CS_POSIX_V6_ILP32_OFF32_LIBS:
76 	case _CS_POSIX_V6_LPBIG_OFFBIG_CFLAGS:
77 	case _CS_POSIX_V6_LPBIG_OFFBIG_LDFLAGS:
78 	case _CS_POSIX_V6_LPBIG_OFFBIG_LIBS:
79 		/*
80 		 * These two environments are never supported.
81 		 */
82 		p = UPE;
83 		goto docopy;
84 
85 	case _CS_POSIX_V6_ILP32_OFFBIG_CFLAGS:
86 	case _CS_POSIX_V6_ILP32_OFFBIG_LDFLAGS:
87 	case _CS_POSIX_V6_ILP32_OFFBIG_LIBS:
88 		if (sizeof(long) * CHAR_BIT == 32 &&
89 		    sizeof(off_t) > sizeof(long))
90 			p = "";
91 		else
92 			p = UPE;
93 		goto docopy;
94 
95 	case _CS_POSIX_V6_LP64_OFF64_CFLAGS:
96 	case _CS_POSIX_V6_LP64_OFF64_LDFLAGS:
97 	case _CS_POSIX_V6_LP64_OFF64_LIBS:
98 		if (sizeof(long) * CHAR_BIT >= 64 &&
99 		    sizeof(void *) * CHAR_BIT >= 64 &&
100 		    sizeof(int) * CHAR_BIT >= 32 &&
101 		    sizeof(off_t) >= sizeof(long))
102 			p = "";
103 		else
104 			p = UPE;
105 		goto docopy;
106 
107 	case _CS_POSIX_V6_WIDTH_RESTRICTED_ENVS:
108 		/* XXX - should have more complete coverage */
109 		if (sizeof(long) * CHAR_BIT >= 64)
110 			p = "_POSIX_V6_LP64_OFF64";
111 		else
112 			p = "_POSIX_V6_ILP32_OFFBIG";
113 		goto docopy;
114 
115 docopy:
116 		if (len != 0 && buf != NULL)
117 			strlcpy(buf, p, len);
118 		return (strlen(p) + 1);
119 
120 	default:
121 		errno = EINVAL;
122 		return (0);
123 	}
124 	/* NOTREACHED */
125 }
126