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 1.18 2003/07/01 09:45:35 alfred Exp $ 18 */ 19 20 #include "namespace.h" 21 #include <sys/types.h> 22 #include <sys/param.h> 23 #include <sys/exec.h> 24 #include <sys/sysctl.h> 25 26 #include <vm/pmap.h> 27 #include <vm/vm.h> 28 #include <vm/vm_param.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 #include "../upmap/upmap.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 * This attempts to support a kernel built in the #2 and #3 era. 46 */ 47 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 #include <stdarg.h> 58 59 #define SPT_BUFSIZE 2048 /* from other parts of sendmail */ 60 61 void 62 setproctitle(const char *fmt, ...) 63 { 64 static struct ps_strings *ps_strings; 65 static char *buf = NULL; 66 static char *obuf = NULL; 67 static char **oargv, *kbuf; 68 static int oargc = -1; 69 static char *nargv[2] = { NULL, NULL }; 70 char **nargvp; 71 int nargc; 72 int i; 73 va_list ap; 74 size_t len; 75 unsigned long ul_ps_strings; 76 int oid[4]; 77 78 va_start(ap, fmt); 79 80 if (__ukp_spt(fmt, ap) == 0) { 81 va_end(ap); 82 return; 83 } 84 85 if (buf == NULL) { 86 buf = malloc(SPT_BUFSIZE); 87 if (buf == NULL) { 88 va_end(ap); 89 return; 90 } 91 nargv[0] = buf; 92 } 93 94 if (obuf == NULL ) { 95 obuf = malloc(SPT_BUFSIZE); 96 if (obuf == NULL) { 97 va_end(ap); 98 return; 99 } 100 *obuf = '\0'; 101 } 102 103 if (fmt) { 104 buf[SPT_BUFSIZE - 1] = '\0'; 105 106 if (fmt[0] == '-') { 107 /* skip program name prefix */ 108 fmt++; 109 len = 0; 110 } else { 111 /* print program name heading for grep */ 112 snprintf(buf, SPT_BUFSIZE, "%s: ", _getprogname()); 113 len = strlen(buf); 114 } 115 116 /* print the argument string */ 117 vsnprintf(buf + len, SPT_BUFSIZE - len, fmt, ap); 118 119 nargvp = nargv; 120 nargc = 1; 121 kbuf = buf; 122 } else if (*obuf != '\0') { 123 /* Idea from NetBSD - reset the title on fmt == NULL */ 124 nargvp = oargv; 125 nargc = oargc; 126 kbuf = obuf; 127 } else { 128 /* Nothing to restore */ 129 va_end(ap); 130 return; 131 } 132 133 va_end(ap); 134 135 /* Set the title into the kernel cached command line */ 136 oid[0] = CTL_KERN; 137 oid[1] = KERN_PROC; 138 oid[2] = KERN_PROC_ARGS; 139 oid[3] = getpid(); 140 sysctl(oid, 4, 0, 0, kbuf, strlen(kbuf) + 1); 141 142 if (ps_strings == NULL) { 143 len = sizeof(ul_ps_strings); 144 if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL, 145 0) == -1) 146 ul_ps_strings = PS_STRINGS; 147 ps_strings = (struct ps_strings *)ul_ps_strings; 148 } 149 150 /* PS_STRINGS points to zeroed memory on a style #2 kernel */ 151 if (ps_strings->ps_argvstr) { 152 /* style #3 */ 153 if (oargc == -1) { 154 /* Record our original args */ 155 oargc = ps_strings->ps_nargvstr; 156 oargv = ps_strings->ps_argvstr; 157 for (i = len = 0; i < oargc; i++) { 158 /* 159 * The program may have scribbled into its 160 * argv array, e.g., to remove some arguments. 161 * If that has happened, break out before 162 * trying to call strlen on a NULL pointer. 163 */ 164 if (oargv[i] == NULL) { 165 oargc = i; 166 break; 167 } 168 snprintf(obuf + len, SPT_BUFSIZE - len, "%s%s", 169 len ? " " : "", oargv[i]); 170 if (len) 171 len++; 172 len += strlen(oargv[i]); 173 if (len >= SPT_BUFSIZE) 174 break; 175 } 176 } 177 ps_strings->ps_nargvstr = nargc; 178 ps_strings->ps_argvstr = nargvp; 179 } else { 180 /* style #2 - we can only restore our first arg :-( */ 181 if (*obuf == '\0') 182 strncpy(obuf, OLD_PS_STRINGS->old_ps_argvstr, 183 SPT_BUFSIZE - 1); 184 OLD_PS_STRINGS->old_ps_nargvstr = 1; 185 OLD_PS_STRINGS->old_ps_argvstr = nargvp[0]; 186 } 187 } 188