1 /* 2 * Copyright (c) 1995 Peter Wemm <peter@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, is permitted provided that the following conditions 7 * are met: 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 15 * Peter Wemm. 16 * 17 * $FreeBSD$ 18 */ 19 20 #include <sys/types.h> 21 #include <sys/param.h> 22 #include <sys/exec.h> 23 #include <sys/sysctl.h> 24 25 #include <vm/vm.h> 26 #include <vm/vm_param.h> 27 #include <vm/pmap.h> 28 29 #include <stdio.h> 30 #include <string.h> 31 #include <stdlib.h> 32 #include <unistd.h> 33 34 /* 35 * Older FreeBSD 2.0, 2.1 and 2.2 had different ps_strings structures and 36 * in different locations. 37 * 1: old_ps_strings at the very top of the stack. 38 * 2: old_ps_strings at SPARE_USRSPACE below the top of the stack. 39 * 3: ps_strings at the very top of the stack. 40 * This attempts to support a kernel built in the #2 and #3 era. 41 */ 42 43 struct old_ps_strings { 44 char *old_ps_argvstr; 45 int old_ps_nargvstr; 46 char *old_ps_envstr; 47 int old_ps_nenvstr; 48 }; 49 #define OLD_PS_STRINGS ((struct old_ps_strings *) \ 50 (USRSTACK - SPARE_USRSPACE - sizeof(struct old_ps_strings))) 51 52 #include <stdarg.h> 53 54 #define SPT_BUFSIZE 2048 /* from other parts of sendmail */ 55 extern char * __progname; /* is this defined in a .h anywhere? */ 56 57 void 58 setproctitle(const char *fmt, ...) 59 { 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 }; 66 char **nargvp; 67 int nargc; 68 int i; 69 va_list ap; 70 size_t len; 71 unsigned long ul_ps_strings; 72 int oid[4]; 73 74 va_start(ap, fmt); 75 76 if (fmt) { 77 buf[sizeof(buf) - 1] = '\0'; 78 79 if (fmt[0] == '-') { 80 /* skip program name prefix */ 81 fmt++; 82 len = 0; 83 } else { 84 /* print program name heading for grep */ 85 (void) snprintf(buf, sizeof(buf), "%s: ", __progname); 86 len = strlen(buf); 87 } 88 89 /* print the argument string */ 90 (void) vsnprintf(buf + len, sizeof(buf) - len, fmt, ap); 91 92 nargvp = nargv; 93 nargc = 1; 94 kbuf = buf; 95 } else if (*obuf != '\0') { 96 /* Idea from NetBSD - reset the title on fmt == NULL */ 97 nargvp = oargv; 98 nargc = oargc; 99 kbuf = obuf; 100 } else 101 /* Nothing to restore */ 102 return; 103 104 va_end(ap); 105 106 /* Set the title into the kernel cached command line */ 107 oid[0] = CTL_KERN; 108 oid[1] = KERN_PROC; 109 oid[2] = KERN_PROC_ARGS; 110 oid[3] = getpid(); 111 sysctl(oid, 4, 0, 0, kbuf, strlen(kbuf) + 1); 112 113 if (ps_strings == NULL) { 114 len = sizeof(ul_ps_strings); 115 if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL, 116 0) == -1) 117 ul_ps_strings = PS_STRINGS; 118 ps_strings = (struct ps_strings *)ul_ps_strings; 119 } 120 121 /* PS_STRINGS points to zeroed memory on a style #2 kernel */ 122 if (ps_strings->ps_argvstr) { 123 /* style #3 */ 124 if (oargc == -1) { 125 /* Record our original args */ 126 oargc = ps_strings->ps_nargvstr; 127 oargv = ps_strings->ps_argvstr; 128 for (i = len = 0; i < oargc; i++) { 129 /* 130 * The program may have scribbled into its 131 * argv array, e.g., to remove some arguments. 132 * If that has happened, break out before 133 * trying to call strlen on a NULL pointer. 134 */ 135 if (oargv[i] == NULL) { 136 oargc = i; 137 break; 138 } 139 snprintf(obuf + len, sizeof(obuf) - len, "%s%s", 140 len ? " " : "", oargv[i]); 141 if (len) 142 len++; 143 len += strlen(oargv[i]); 144 if (len >= sizeof(obuf)) 145 break; 146 } 147 } 148 ps_strings->ps_nargvstr = nargc; 149 ps_strings->ps_argvstr = nargvp; 150 } else { 151 /* style #2 - we can only restore our first arg :-( */ 152 if (*obuf == '\0') 153 strncpy(obuf, OLD_PS_STRINGS->old_ps_argvstr, 154 sizeof(obuf) - 1); 155 OLD_PS_STRINGS->old_ps_nargvstr = 1; 156 OLD_PS_STRINGS->old_ps_argvstr = nargvp[0]; 157 } 158 } 159