freebsd-nq/lib/libc/gen/setproctitle.c
John Polstra 4113386c62 When recording the original arguments, don't (ab)use "nargc" for
iterating over the arguments.  Doing so wipes out the value which
is about to be stored into the ps_strings structure.
2000-12-04 01:26:29 +00:00

149 lines
3.8 KiB
C

/*
* Copyright (c) 1995 Peter Wemm <peter@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, is permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice immediately at the beginning of the file, without modification,
* this list of conditions, and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Absolutely no warranty of function or purpose is made by the author
* Peter Wemm.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/exec.h>
#include <sys/sysctl.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
/*
* Older FreeBSD 2.0, 2.1 and 2.2 had different ps_strings structures and
* in different locations.
* 1: old_ps_strings at the very top of the stack.
* 2: old_ps_strings at SPARE_USRSPACE below the top of the stack.
* 3: ps_strings at the very top of the stack.
* This attempts to support a kernel built in the #2 and #3 era.
*/
struct old_ps_strings {
char *old_ps_argvstr;
int old_ps_nargvstr;
char *old_ps_envstr;
int old_ps_nenvstr;
};
#define OLD_PS_STRINGS ((struct old_ps_strings *) \
(USRSTACK - SPARE_USRSPACE - sizeof(struct old_ps_strings)))
#include <stdarg.h>
#define SPT_BUFSIZE 2048 /* from other parts of sendmail */
extern char * __progname; /* is this defined in a .h anywhere? */
void
setproctitle(const char *fmt, ...)
{
static struct ps_strings *ps_strings;
static char buf[SPT_BUFSIZE];
static char obuf[SPT_BUFSIZE];
static char **oargv, *kbuf;
static int oargc = -1;
static char *nargv[2] = { buf, NULL };
char **nargvp;
int nargc;
int i;
va_list ap;
size_t len;
unsigned long ul_ps_strings;
int oid[4];
va_start(ap, fmt);
if (fmt) {
buf[sizeof(buf) - 1] = '\0';
if (fmt[0] == '-') {
/* skip program name prefix */
fmt++;
len = 0;
} else {
/* print program name heading for grep */
(void) snprintf(buf, sizeof(buf), "%s: ", __progname);
len = strlen(buf);
}
/* print the argument string */
(void) vsnprintf(buf + len, sizeof(buf) - len, fmt, ap);
nargvp = nargv;
nargc = 1;
kbuf = buf;
} else if (*obuf != '\0') {
/* Idea from NetBSD - reset the title on fmt == NULL */
nargvp = oargv;
nargc = oargc;
kbuf = obuf;
} else
/* Nothing to restore */
return;
va_end(ap);
/* Set the title into the kernel cached command line */
oid[0] = CTL_KERN;
oid[1] = KERN_PROC;
oid[2] = KERN_PROC_ARGS;
oid[3] = getpid();
sysctl(oid, 4, 0, 0, kbuf, strlen(kbuf) + 1);
if (ps_strings == NULL) {
len = sizeof(ul_ps_strings);
if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL,
0) == -1)
ul_ps_strings = PS_STRINGS;
ps_strings = (struct ps_strings *)ul_ps_strings;
}
/* PS_STRINGS points to zeroed memory on a style #2 kernel */
if (ps_strings->ps_argvstr) {
/* style #3 */
if (oargc == -1) {
/* Record our original args */
oargc = ps_strings->ps_nargvstr;
oargv = ps_strings->ps_argvstr;
for (i = len = 0; i < oargc; i++) {
snprintf(obuf + len, sizeof(obuf) - len, "%s%s",
len ? " " : "", oargv[i]);
if (len)
len++;
len += strlen(oargv[i]);
if (len >= sizeof(obuf))
break;
}
}
ps_strings->ps_nargvstr = nargc;
ps_strings->ps_argvstr = nargvp;
} else {
/* style #2 - we can only restore our first arg :-( */
if (*obuf == '\0')
strncpy(obuf, OLD_PS_STRINGS->old_ps_argvstr,
sizeof(obuf) - 1);
OLD_PS_STRINGS->old_ps_nargvstr = 1;
OLD_PS_STRINGS->old_ps_argvstr = nargvp[0];
}
}