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: 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 1.4 2005/03/09 18:52:21 joerg Exp $ 19 */ 20 21 #include <sys/types.h> 22 #include <sys/param.h> 23 #include <sys/exec.h> 24 #include <sys/sysctl.h> 25 26 #include <vm/vm.h> 27 #include <vm/vm_param.h> 28 #include <vm/pmap.h> 29 30 #include <stdio.h> 31 #include <string.h> 32 #include <stdlib.h> 33 #include <unistd.h> 34 35 /* 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. 42 */ 43 44 struct old_ps_strings { 45 char *old_ps_argvstr; 46 int old_ps_nargvstr; 47 char *old_ps_envstr; 48 int old_ps_nenvstr; 49 }; 50 #define OLD_PS_STRINGS ((struct old_ps_strings *) \ 51 (USRSTACK - SPARE_USRSPACE - sizeof(struct old_ps_strings))) 52 53 #include <stdarg.h> 54 55 #define SPT_BUFSIZE 2048 /* from other parts of sendmail */ 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: ", getprogname()); 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 #ifdef __i386__ 114 if (ps_strings == NULL) { 115 len = sizeof(ul_ps_strings); 116 if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL, 117 0) == -1) 118 ul_ps_strings = PS_STRINGS; 119 ps_strings = (struct ps_strings *)ul_ps_strings; 120 } 121 122 /* PS_STRINGS points to zeroed memory on a style #2 kernel */ 123 if (ps_strings->ps_argvstr) { 124 /* style #3 */ 125 if (oargc == -1) { 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++) { 130 /* 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. 135 */ 136 if (oargv[i] == NULL) { 137 oargc = i; 138 break; 139 } 140 snprintf(obuf + len, sizeof(obuf) - len, "%s%s", 141 len ? " " : "", oargv[i]); 142 if (len) 143 len++; 144 len += strlen(oargv[i]); 145 if (len >= sizeof(obuf)) 146 break; 147 } 148 } 149 ps_strings->ps_nargvstr = nargc; 150 ps_strings->ps_argvstr = nargvp; 151 } else { 152 /* style #2 - we can only restore our first arg :-( */ 153 if (*obuf == '\0') 154 strncpy(obuf, OLD_PS_STRINGS->old_ps_argvstr, 155 sizeof(obuf) - 1); 156 OLD_PS_STRINGS->old_ps_nargvstr = 1; 157 OLD_PS_STRINGS->old_ps_argvstr = nargvp[0]; 158 } 159 #endif 160 } 161