xref: /netbsd-src/lib/libc/gen/setproctitle.c (revision c293541954fa052339db7f821e62c98dfa3db4e1)
1 /* $NetBSD: setproctitle.c,v 1.18 2000/06/29 06:31:44 mrg Exp $ */
2 
3 /*
4  * Copyright (c) 1994, 1995 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *          This product includes software developed for the
18  *          NetBSD Project.  See http://www.netbsd.org/ for
19  *          information about NetBSD.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *
34  * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
35  */
36 
37 #include <sys/cdefs.h>
38 #if defined(LIBC_SCCS) && !defined(lint)
39 __RCSID("$NetBSD: setproctitle.c,v 1.18 2000/06/29 06:31:44 mrg Exp $");
40 #endif /* LIBC_SCCS and not lint */
41 
42 #include "namespace.h"
43 #include <sys/param.h>
44 #include <sys/types.h>
45 #include <sys/exec.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 
50 #ifdef __STDC__
51 #include <stdarg.h>
52 #else
53 #include <varargs.h>
54 #endif
55 
56 #ifdef __weak_alias
57 __weak_alias(setproctitle,_setproctitle)
58 #endif
59 
60 #define	MAX_PROCTITLE	2048
61 
62 extern char *__progname;		/* Program name, from crt0. */
63 
64 /*
65  * For compatibility with old versions of crt0 that didn't define __ps_strings,
66  * define it as a common here.
67  */
68 struct ps_strings *__ps_strings;
69 
70 void
71 #if __STDC__
72 setproctitle(const char *fmt, ...)
73 #else
74 setproctitle(fmt, va_alist)
75 	const char *fmt;
76 	va_dcl
77 #endif
78 {
79 	va_list ap;
80 	static char buf[MAX_PROCTITLE], *bufp;
81 	int used;
82 
83 #if __STDC__
84 	va_start(ap, fmt);
85 #else
86 	va_start(ap);
87 #endif
88 	if (fmt != NULL) {
89 		used = snprintf(buf, (size_t)MAX_PROCTITLE, "%s: ", __progname);
90 		(void)vsnprintf(buf + used, (size_t)(MAX_PROCTITLE - used),
91 		    fmt, ap);
92 	} else
93 		(void)snprintf(buf, MAX_PROCTITLE, "%s", __progname);
94 	va_end(ap);
95 
96 	bufp = buf;
97 
98 #ifdef	USRSTACK
99 	/*
100 	 * For compatibility with old versions of crt0 and old kernels, set
101 	 * __ps_strings to a default value if it's null.
102 	 * But only if USRSTACK is defined.  It might not be defined if
103 	 * user-level code can not assume it's a constant (i.e. m68k).
104 	 */
105 	if (__ps_strings == 0)
106 		__ps_strings = PS_STRINGS;
107 #endif	/* USRSTACK */
108 
109 	if (__ps_strings != 0) {
110 		__ps_strings->ps_nargvstr = 1;
111 		__ps_strings->ps_argvstr = &bufp;
112 	}
113 }
114