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 * $DragonFly: src/lib/libc/gen/setproctitle.c,v 1.5 2005/11/13 00:07:42 swildner Exp $ 19 */ 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 * 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 if (buf == NULL) { 79 buf = malloc(SPT_BUFSIZE); 80 if (buf == NULL) 81 return; 82 nargv[0] = buf; 83 } 84 85 if (obuf == NULL ) { 86 obuf = malloc(SPT_BUFSIZE); 87 if (obuf == NULL) 88 return; 89 *obuf = '\0'; 90 } 91 92 va_start(ap, fmt); 93 94 if (fmt) { 95 buf[SPT_BUFSIZE - 1] = '\0'; 96 97 if (fmt[0] == '-') { 98 /* skip program name prefix */ 99 fmt++; 100 len = 0; 101 } else { 102 /* print program name heading for grep */ 103 snprintf(buf, SPT_BUFSIZE, "%s: ", _getprogname()); 104 len = strlen(buf); 105 } 106 107 /* print the argument string */ 108 vsnprintf(buf + len, SPT_BUFSIZE - len, fmt, ap); 109 110 nargvp = nargv; 111 nargc = 1; 112 kbuf = buf; 113 } else if (*obuf != '\0') { 114 /* Idea from NetBSD - reset the title on fmt == NULL */ 115 nargvp = oargv; 116 nargc = oargc; 117 kbuf = obuf; 118 } else 119 /* Nothing to restore */ 120 return; 121 122 va_end(ap); 123 124 /* Set the title into the kernel cached command line */ 125 oid[0] = CTL_KERN; 126 oid[1] = KERN_PROC; 127 oid[2] = KERN_PROC_ARGS; 128 oid[3] = getpid(); 129 sysctl(oid, 4, 0, 0, kbuf, strlen(kbuf) + 1); 130 131 if (ps_strings == NULL) { 132 len = sizeof(ul_ps_strings); 133 if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL, 134 0) == -1) 135 ul_ps_strings = PS_STRINGS; 136 ps_strings = (struct ps_strings *)ul_ps_strings; 137 } 138 139 /* PS_STRINGS points to zeroed memory on a style #2 kernel */ 140 if (ps_strings->ps_argvstr) { 141 /* style #3 */ 142 if (oargc == -1) { 143 /* Record our original args */ 144 oargc = ps_strings->ps_nargvstr; 145 oargv = ps_strings->ps_argvstr; 146 for (i = len = 0; i < oargc; i++) { 147 /* 148 * The program may have scribbled into its 149 * argv array, e.g., to remove some arguments. 150 * If that has happened, break out before 151 * trying to call strlen on a NULL pointer. 152 */ 153 if (oargv[i] == NULL) { 154 oargc = i; 155 break; 156 } 157 snprintf(obuf + len, SPT_BUFSIZE - len, "%s%s", 158 len ? " " : "", oargv[i]); 159 if (len) 160 len++; 161 len += strlen(oargv[i]); 162 if (len >= SPT_BUFSIZE) 163 break; 164 } 165 } 166 ps_strings->ps_nargvstr = nargc; 167 ps_strings->ps_argvstr = nargvp; 168 } else { 169 /* style #2 - we can only restore our first arg :-( */ 170 if (*obuf == '\0') 171 strncpy(obuf, OLD_PS_STRINGS->old_ps_argvstr, 172 SPT_BUFSIZE - 1); 173 OLD_PS_STRINGS->old_ps_nargvstr = 1; 174 OLD_PS_STRINGS->old_ps_argvstr = nargvp[0]; 175 } 176 } 177