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/types.h> 23 #include <sys/param.h> 24 #include <sys/exec.h> 25 #include <sys/sysctl.h> 26 27 #include <vm/vm.h> 28 #include <vm/vm_param.h> 29 #include <vm/pmap.h> 30 31 #include <stdio.h> 32 #include <string.h> 33 #include <stdlib.h> 34 #include <unistd.h> 35 #include "un-namespace.h" 36 37 #include "libc_private.h" 38 39 /* 40 * Older FreeBSD 2.0, 2.1 and 2.2 had different ps_strings structures and 41 * in different locations. 42 * 1: old_ps_strings at the very top of the stack. 43 * 2: old_ps_strings at SPARE_USRSPACE below the top of the stack. 44 * 3: ps_strings at the very top of the stack. 45 * We only support a kernel providing #3 style ps_strings. 46 * 47 * For historical purposes, a definition of the old ps_strings structure 48 * and location is preserved below: 49 struct old_ps_strings { 50 char *old_ps_argvstr; 51 int old_ps_nargvstr; 52 char *old_ps_envstr; 53 int old_ps_nenvstr; 54 }; 55 #define OLD_PS_STRINGS ((struct old_ps_strings *) \ 56 (USRSTACK - SPARE_USRSPACE - sizeof(struct old_ps_strings))) 57 */ 58 59 #include <stdarg.h> 60 61 #define SPT_BUFSIZE 2048 /* from other parts of sendmail */ 62 63 void 64 setproctitle(const char *fmt, ...) 65 { 66 static struct ps_strings *ps_strings; 67 static char *buf = NULL; 68 static char *obuf = NULL; 69 static char **oargv, *kbuf; 70 static int oargc = -1; 71 static char *nargv[2] = { NULL, NULL }; 72 char **nargvp; 73 int nargc; 74 int i; 75 va_list ap; 76 size_t len; 77 unsigned long ul_ps_strings; 78 int oid[4]; 79 80 if (buf == NULL) { 81 buf = malloc(SPT_BUFSIZE); 82 if (buf == NULL) 83 return; 84 nargv[0] = buf; 85 } 86 87 if (obuf == NULL ) { 88 obuf = malloc(SPT_BUFSIZE); 89 if (obuf == NULL) 90 return; 91 *obuf = '\0'; 92 } 93 94 va_start(ap, fmt); 95 96 if (fmt) { 97 buf[SPT_BUFSIZE - 1] = '\0'; 98 99 if (fmt[0] == '-') { 100 /* skip program name prefix */ 101 fmt++; 102 len = 0; 103 } else { 104 /* print program name heading for grep */ 105 (void)snprintf(buf, SPT_BUFSIZE, "%s: ", _getprogname()); 106 len = strlen(buf); 107 } 108 109 /* print the argument string */ 110 (void) vsnprintf(buf + len, SPT_BUFSIZE - len, fmt, ap); 111 112 nargvp = nargv; 113 nargc = 1; 114 kbuf = buf; 115 } else if (*obuf != '\0') { 116 /* Idea from NetBSD - reset the title on fmt == NULL */ 117 nargvp = oargv; 118 nargc = oargc; 119 kbuf = obuf; 120 } else 121 /* Nothing to restore */ 122 return; 123 124 va_end(ap); 125 126 /* Set the title into the kernel cached command line */ 127 oid[0] = CTL_KERN; 128 oid[1] = KERN_PROC; 129 oid[2] = KERN_PROC_ARGS; 130 oid[3] = getpid(); 131 sysctl(oid, 4, 0, 0, kbuf, strlen(kbuf) + 1); 132 133 if (ps_strings == NULL) { 134 len = sizeof(ul_ps_strings); 135 if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL, 136 0) == -1) 137 ul_ps_strings = PS_STRINGS; 138 ps_strings = (struct ps_strings *)ul_ps_strings; 139 } 140 141 /* 142 * PS_STRINGS points to zeroed memory on a style #2 kernel. 143 * Should not happen. 144 */ 145 if (ps_strings->ps_argvstr == NULL) 146 return; 147 148 /* style #3 */ 149 if (oargc == -1) { 150 /* Record our original args */ 151 oargc = ps_strings->ps_nargvstr; 152 oargv = ps_strings->ps_argvstr; 153 for (i = len = 0; i < oargc; i++) { 154 /* 155 * The program may have scribbled into its 156 * argv array, e.g., to remove some arguments. 157 * If that has happened, break out before 158 * trying to call strlen on a NULL pointer. 159 */ 160 if (oargv[i] == NULL) { 161 oargc = i; 162 break; 163 } 164 snprintf(obuf + len, SPT_BUFSIZE - len, "%s%s", 165 len != 0 ? " " : "", oargv[i]); 166 if (len != 0) 167 len++; 168 len += strlen(oargv[i]); 169 if (len >= SPT_BUFSIZE) 170 break; 171 } 172 } 173 ps_strings->ps_nargvstr = nargc; 174 ps_strings->ps_argvstr = nargvp; 175 } 176