2 * Copyright (c) 1995 Peter Wemm <peter@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, is permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice immediately at the beginning of the file, without modification,
10 * this list of conditions, and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Absolutely no warranty of function or purpose is made by the author
17 * $FreeBSD: src/lib/libc/gen/setproctitle.c,v 1.12.2.2 2000/12/10 20:27:08 jdp Exp $
18 * $DragonFly: src/lib/libc/gen/setproctitle.c,v 1.5 2005/11/13 00:07:42 swildner Exp $
21 #include <sys/types.h>
22 #include <sys/param.h>
24 #include <sys/sysctl.h>
27 #include <vm/vm_param.h>
36 * Older FreeBSD 2.0, 2.1 and 2.2 had different ps_strings structures and
37 * in different locations.
38 * 1: old_ps_strings at the very top of the stack.
39 * 2: old_ps_strings at SPARE_USRSPACE below the top of the stack.
40 * 3: ps_strings at the very top of the stack.
41 * This attempts to support a kernel built in the #2 and #3 era.
44 struct old_ps_strings {
50 #define OLD_PS_STRINGS ((struct old_ps_strings *) \
51 (USRSTACK - SPARE_USRSPACE - sizeof(struct old_ps_strings)))
55 #define SPT_BUFSIZE 2048 /* from other parts of sendmail */
58 setproctitle(const char *fmt, ...)
60 static struct ps_strings *ps_strings;
61 static char buf[SPT_BUFSIZE];
62 static char obuf[SPT_BUFSIZE];
63 static char **oargv, *kbuf;
64 static int oargc = -1;
65 static char *nargv[2] = { buf, NULL };
71 unsigned long ul_ps_strings;
77 buf[sizeof(buf) - 1] = '\0';
80 /* skip program name prefix */
84 /* print program name heading for grep */
85 snprintf(buf, sizeof(buf), "%s: ", getprogname());
89 /* print the argument string */
90 vsnprintf(buf + len, sizeof(buf) - len, fmt, ap);
95 } else if (*obuf != '\0') {
96 /* Idea from NetBSD - reset the title on fmt == NULL */
101 /* Nothing to restore */
106 /* Set the title into the kernel cached command line */
109 oid[2] = KERN_PROC_ARGS;
111 sysctl(oid, 4, 0, 0, kbuf, strlen(kbuf) + 1);
114 if (ps_strings == NULL) {
115 len = sizeof(ul_ps_strings);
116 if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL,
118 ul_ps_strings = PS_STRINGS;
119 ps_strings = (struct ps_strings *)ul_ps_strings;
122 /* PS_STRINGS points to zeroed memory on a style #2 kernel */
123 if (ps_strings->ps_argvstr) {
126 /* Record our original args */
127 oargc = ps_strings->ps_nargvstr;
128 oargv = ps_strings->ps_argvstr;
129 for (i = len = 0; i < oargc; i++) {
131 * The program may have scribbled into its
132 * argv array, e.g., to remove some arguments.
133 * If that has happened, break out before
134 * trying to call strlen on a NULL pointer.
136 if (oargv[i] == NULL) {
140 snprintf(obuf + len, sizeof(obuf) - len, "%s%s",
141 len ? " " : "", oargv[i]);
144 len += strlen(oargv[i]);
145 if (len >= sizeof(obuf))
149 ps_strings->ps_nargvstr = nargc;
150 ps_strings->ps_argvstr = nargvp;
152 /* style #2 - we can only restore our first arg :-( */
154 strncpy(obuf, OLD_PS_STRINGS->old_ps_argvstr,
156 OLD_PS_STRINGS->old_ps_nargvstr = 1;
157 OLD_PS_STRINGS->old_ps_argvstr = nargvp[0];