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 #include "../upmap/upmap.h" 39 40 /* 41 * Older FreeBSD 2.0, 2.1 and 2.2 had different ps_strings structures and 42 * in different locations. 43 * 1: old_ps_strings at the very top of the stack. 44 * 2: old_ps_strings at SPARE_USRSPACE below the top of the stack. 45 * 3: ps_strings at the very top of the stack. 46 * This attempts to support a kernel built in the #2 and #3 era. 47 */ 48 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 #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 va_start(ap, fmt); 80 81 if (__ukp_spt(fmt, ap) == 0) 82 return; 83 84 if (buf == NULL) { 85 buf = malloc(SPT_BUFSIZE); 86 if (buf == NULL) 87 return; 88 nargv[0] = buf; 89 } 90 91 if (obuf == NULL ) { 92 obuf = malloc(SPT_BUFSIZE); 93 if (obuf == NULL) 94 return; 95 *obuf = '\0'; 96 } 97 98 if (fmt) { 99 buf[SPT_BUFSIZE - 1] = '\0'; 100 101 if (fmt[0] == '-') { 102 /* skip program name prefix */ 103 fmt++; 104 len = 0; 105 } else { 106 /* print program name heading for grep */ 107 snprintf(buf, SPT_BUFSIZE, "%s: ", _getprogname()); 108 len = strlen(buf); 109 } 110 111 /* print the argument string */ 112 vsnprintf(buf + len, SPT_BUFSIZE - len, fmt, ap); 113 114 nargvp = nargv; 115 nargc = 1; 116 kbuf = buf; 117 } else if (*obuf != '\0') { 118 /* Idea from NetBSD - reset the title on fmt == NULL */ 119 nargvp = oargv; 120 nargc = oargc; 121 kbuf = obuf; 122 } else 123 /* Nothing to restore */ 124 return; 125 126 va_end(ap); 127 128 /* Set the title into the kernel cached command line */ 129 oid[0] = CTL_KERN; 130 oid[1] = KERN_PROC; 131 oid[2] = KERN_PROC_ARGS; 132 oid[3] = getpid(); 133 sysctl(oid, 4, 0, 0, kbuf, strlen(kbuf) + 1); 134 135 if (ps_strings == NULL) { 136 len = sizeof(ul_ps_strings); 137 if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL, 138 0) == -1) 139 ul_ps_strings = PS_STRINGS; 140 ps_strings = (struct ps_strings *)ul_ps_strings; 141 } 142 143 /* PS_STRINGS points to zeroed memory on a style #2 kernel */ 144 if (ps_strings->ps_argvstr) { 145 /* style #3 */ 146 if (oargc == -1) { 147 /* Record our original args */ 148 oargc = ps_strings->ps_nargvstr; 149 oargv = ps_strings->ps_argvstr; 150 for (i = len = 0; i < oargc; i++) { 151 /* 152 * The program may have scribbled into its 153 * argv array, e.g., to remove some arguments. 154 * If that has happened, break out before 155 * trying to call strlen on a NULL pointer. 156 */ 157 if (oargv[i] == NULL) { 158 oargc = i; 159 break; 160 } 161 snprintf(obuf + len, SPT_BUFSIZE - len, "%s%s", 162 len ? " " : "", oargv[i]); 163 if (len) 164 len++; 165 len += strlen(oargv[i]); 166 if (len >= SPT_BUFSIZE) 167 break; 168 } 169 } 170 ps_strings->ps_nargvstr = nargc; 171 ps_strings->ps_argvstr = nargvp; 172 } else { 173 /* style #2 - we can only restore our first arg :-( */ 174 if (*obuf == '\0') 175 strncpy(obuf, OLD_PS_STRINGS->old_ps_argvstr, 176 SPT_BUFSIZE - 1); 177 OLD_PS_STRINGS->old_ps_nargvstr = 1; 178 OLD_PS_STRINGS->old_ps_argvstr = nargvp[0]; 179 } 180 } 181