xref: /freebsd/lib/libc/gen/confstr.c (revision 2f02600abfddfc4e9f20dd384a2e729b451e16bd)
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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid[] = "@(#)confstr.c	8.1 (Berkeley) 6/4/93";
32 #endif /* LIBC_SCCS and not lint */
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 
38 #include <errno.h>
39 #include <limits.h>
40 #include <paths.h>
41 #include <string.h>
42 #include <unistd.h>
43 
44 
45 size_t
46 confstr(int name, char *buf, size_t len)
47 {
48 	const char *p;
49 	const char UPE[] = "unsupported programming environment";
50 
51 	switch (name) {
52 	case _CS_PATH:
53 		p = _PATH_STDPATH;
54 		goto docopy;
55 
56 		/*
57 		 * POSIX/SUS ``Programming Environments'' stuff
58 		 *
59 		 * We don't support more than one programming environment
60 		 * on any platform (yet), so we just return the empty
61 		 * string for the environment we are compiled for,
62 		 * and the string "unsupported programming environment"
63 		 * for anything else.  (The Standard says that if these
64 		 * values are used on a system which does not support
65 		 * this environment -- determined via sysconf() -- then
66 		 * the value we return is unspecified.  So, we return
67 		 * something which will cause obvious breakage.)
68 		 */
69 	case _CS_POSIX_V6_ILP32_OFF32_CFLAGS:
70 	case _CS_POSIX_V6_ILP32_OFF32_LDFLAGS:
71 	case _CS_POSIX_V6_ILP32_OFF32_LIBS:
72 	case _CS_POSIX_V6_LPBIG_OFFBIG_CFLAGS:
73 	case _CS_POSIX_V6_LPBIG_OFFBIG_LDFLAGS:
74 	case _CS_POSIX_V6_LPBIG_OFFBIG_LIBS:
75 		/*
76 		 * These two environments are never supported.
77 		 */
78 		p = UPE;
79 		goto docopy;
80 
81 	case _CS_POSIX_V6_ILP32_OFFBIG_CFLAGS:
82 	case _CS_POSIX_V6_ILP32_OFFBIG_LDFLAGS:
83 	case _CS_POSIX_V6_ILP32_OFFBIG_LIBS:
84 		if (sizeof(long) * CHAR_BIT == 32 &&
85 		    sizeof(off_t) > sizeof(long))
86 			p = "";
87 		else
88 			p = UPE;
89 		goto docopy;
90 
91 	case _CS_POSIX_V6_LP64_OFF64_CFLAGS:
92 	case _CS_POSIX_V6_LP64_OFF64_LDFLAGS:
93 	case _CS_POSIX_V6_LP64_OFF64_LIBS:
94 		if (sizeof(long) * CHAR_BIT >= 64 &&
95 		    sizeof(void *) * CHAR_BIT >= 64 &&
96 		    sizeof(int) * CHAR_BIT >= 32 &&
97 		    sizeof(off_t) >= sizeof(long))
98 			p = "";
99 		else
100 			p = UPE;
101 		goto docopy;
102 
103 	case _CS_POSIX_V6_WIDTH_RESTRICTED_ENVS:
104 		/* XXX - should have more complete coverage */
105 		if (sizeof(long) * CHAR_BIT >= 64)
106 			p = "_POSIX_V6_LP64_OFF64";
107 		else
108 			p = "_POSIX_V6_ILP32_OFFBIG";
109 		goto docopy;
110 
111 docopy:
112 		if (len != 0 && buf != NULL)
113 			strlcpy(buf, p, len);
114 		return (strlen(p) + 1);
115 
116 	default:
117 		errno = EINVAL;
118 		return (0);
119 	}
120 	/* NOTREACHED */
121 }
122