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 18 #include <sys/cdefs.h> 19 __FBSDID("$FreeBSD$"); 20 21 #include "namespace.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 #include "un-namespace.h" 35 36 #include "libc_private.h" 37 38 /* 39 * Older FreeBSD 2.0, 2.1 and 2.2 had different ps_strings structures and 40 * in different locations. 41 * 1: old_ps_strings at the very top of the stack. 42 * 2: old_ps_strings at SPARE_USRSPACE below the top of the stack. 43 * 3: ps_strings at the very top of the stack. 44 * We only support a kernel providing #3 style ps_strings. 45 * 46 * For historical purposes, a definition of the old ps_strings structure 47 * and location is preserved below: 48 struct old_ps_strings { 49 char *old_ps_argvstr; 50 int old_ps_nargvstr; 51 char *old_ps_envstr; 52 int old_ps_nenvstr; 53 }; 54 #define OLD_PS_STRINGS ((struct old_ps_strings *) \ 55 (USRSTACK - SPARE_USRSPACE - sizeof(struct old_ps_strings))) 56 */ 57 58 #include <stdarg.h> 59 60 #define SPT_BUFSIZE 2048 /* from other parts of sendmail */ 61 62 void 63 setproctitle(const char *fmt, ...) 64 { 65 static struct ps_strings *ps_strings; 66 static char *buf = NULL; 67 static char *obuf = NULL; 68 static char **oargv, *kbuf; 69 static int oargc = -1; 70 static char *nargv[2] = { NULL, NULL }; 71 char **nargvp; 72 int nargc; 73 int i; 74 va_list ap; 75 size_t len; 76 unsigned long ul_ps_strings; 77 int oid[4]; 78 79 if (buf == NULL) { 80 buf = malloc(SPT_BUFSIZE); 81 if (buf == NULL) 82 return; 83 nargv[0] = buf; 84 } 85 86 if (obuf == NULL ) { 87 obuf = malloc(SPT_BUFSIZE); 88 if (obuf == NULL) 89 return; 90 *obuf = '\0'; 91 } 92 93 va_start(ap, fmt); 94 95 if (fmt) { 96 buf[SPT_BUFSIZE - 1] = '\0'; 97 98 if (fmt[0] == '-') { 99 /* skip program name prefix */ 100 fmt++; 101 len = 0; 102 } else { 103 /* print program name heading for grep */ 104 (void)snprintf(buf, SPT_BUFSIZE, "%s: ", _getprogname()); 105 len = strlen(buf); 106 } 107 108 /* print the argument string */ 109 (void) vsnprintf(buf + len, SPT_BUFSIZE - len, fmt, ap); 110 111 nargvp = nargv; 112 nargc = 1; 113 kbuf = buf; 114 } else if (*obuf != '\0') { 115 /* Idea from NetBSD - reset the title on fmt == NULL */ 116 nargvp = oargv; 117 nargc = oargc; 118 kbuf = obuf; 119 } else 120 /* Nothing to restore */ 121 return; 122 123 va_end(ap); 124 125 /* Set the title into the kernel cached command line */ 126 oid[0] = CTL_KERN; 127 oid[1] = KERN_PROC; 128 oid[2] = KERN_PROC_ARGS; 129 oid[3] = getpid(); 130 sysctl(oid, 4, 0, 0, kbuf, strlen(kbuf) + 1); 131 132 if (ps_strings == NULL) { 133 len = sizeof(ul_ps_strings); 134 if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL, 135 0) == -1) 136 return; 137 ps_strings = (struct ps_strings *)ul_ps_strings; 138 } 139 140 /* 141 * PS_STRINGS points to zeroed memory on a style #2 kernel. 142 * Should not happen. 143 */ 144 if (ps_strings->ps_argvstr == NULL) 145 return; 146 147 /* style #3 */ 148 if (oargc == -1) { 149 /* Record our original args */ 150 oargc = ps_strings->ps_nargvstr; 151 oargv = ps_strings->ps_argvstr; 152 for (i = len = 0; i < oargc; i++) { 153 /* 154 * The program may have scribbled into its 155 * argv array, e.g., to remove some arguments. 156 * If that has happened, break out before 157 * trying to call strlen on a NULL pointer. 158 */ 159 if (oargv[i] == NULL) { 160 oargc = i; 161 break; 162 } 163 snprintf(obuf + len, SPT_BUFSIZE - len, "%s%s", 164 len != 0 ? " " : "", oargv[i]); 165 if (len != 0) 166 len++; 167 len += strlen(oargv[i]); 168 if (len >= SPT_BUFSIZE) 169 break; 170 } 171 } 172 ps_strings->ps_nargvstr = nargc; 173 ps_strings->ps_argvstr = nargvp; 174 } 175