1 /*- 2 * SPDX-License-Identifier: BSD-4-Clause 3 * 4 * Copyright 1997 Sean Eric Fagan 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, 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. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by Sean Eric Fagan 17 * 4. Neither the name of the author may be used to endorse or promote 18 * products derived from this software without specific prior written 19 * permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 /* 38 * The main module for truss. Surprisingly simple, but, then, the other 39 * files handle the bulk of the work. And, of course, the kernel has to 40 * do a lot of the work :). 41 */ 42 43 #include <sys/ptrace.h> 44 45 #include <err.h> 46 #include <signal.h> 47 #include <stdbool.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <sysdecode.h> 51 #include <time.h> 52 #include <unistd.h> 53 54 #include "truss.h" 55 #include "extern.h" 56 #include "syscall.h" 57 58 static __dead2 void 59 usage(void) 60 { 61 fprintf(stderr, "%s\n%s\n", 62 "usage: truss [-cfaedDHS] [-o file] [-s strsize] -p pid", 63 " truss [-cfaedDHS] [-o file] [-s strsize] command [args]"); 64 exit(1); 65 } 66 67 int 68 main(int ac, char **av) 69 { 70 struct sigaction sa; 71 struct trussinfo *trussinfo; 72 char *fname; 73 char **command; 74 const char *errstr; 75 pid_t pid; 76 int c; 77 78 fname = NULL; 79 80 /* Initialize the trussinfo struct */ 81 trussinfo = (struct trussinfo *)calloc(1, sizeof(struct trussinfo)); 82 if (trussinfo == NULL) 83 errx(1, "calloc() failed"); 84 85 pid = 0; 86 trussinfo->outfile = stderr; 87 trussinfo->strsize = 32; 88 trussinfo->curthread = NULL; 89 LIST_INIT(&trussinfo->proclist); 90 while ((c = getopt(ac, av, "p:o:facedDs:SH")) != -1) { 91 switch (c) { 92 case 'p': /* specified pid */ 93 pid = atoi(optarg); 94 /* make sure i don't trace me */ 95 if (pid == getpid()) { 96 errx(2, "attempt to grab self."); 97 } 98 break; 99 case 'f': /* Follow fork()'s */ 100 trussinfo->flags |= FOLLOWFORKS; 101 break; 102 case 'a': /* Print execve() argument strings. */ 103 trussinfo->flags |= EXECVEARGS; 104 break; 105 case 'c': /* Count number of system calls and time. */ 106 trussinfo->flags |= (COUNTONLY | NOSIGS); 107 break; 108 case 'e': /* Print execve() environment strings. */ 109 trussinfo->flags |= EXECVEENVS; 110 break; 111 case 'd': /* Absolute timestamps */ 112 trussinfo->flags |= ABSOLUTETIMESTAMPS; 113 break; 114 case 'D': /* Relative timestamps */ 115 trussinfo->flags |= RELATIVETIMESTAMPS; 116 break; 117 case 'o': /* Specified output file */ 118 fname = optarg; 119 break; 120 case 's': /* Specified string size */ 121 trussinfo->strsize = (int)strtonum(optarg, 0, INT_MAX, 122 &errstr); 123 if (errstr) 124 errx(1, "maximum string size is %s: %s", errstr, optarg); 125 break; 126 case 'S': /* Don't trace signals */ 127 trussinfo->flags |= NOSIGS; 128 break; 129 case 'H': 130 trussinfo->flags |= DISPLAYTIDS; 131 break; 132 default: 133 usage(); 134 } 135 } 136 137 ac -= optind; av += optind; 138 if ((pid == 0 && ac == 0) || 139 (pid != 0 && ac != 0)) 140 usage(); 141 142 if (fname != NULL) { /* Use output file */ 143 /* 144 * Set close-on-exec ('e'), so that the output file is not 145 * shared with the traced process. 146 */ 147 if ((trussinfo->outfile = fopen(fname, "we")) == NULL) 148 err(1, "cannot open %s", fname); 149 } 150 151 /* 152 * If truss starts the process itself, it will ignore some signals -- 153 * they should be passed off to the process, which may or may not 154 * exit. If, however, we are examining an already-running process, 155 * then we restore the event mask on these same signals. 156 */ 157 if (pid == 0) { 158 /* Start a command ourselves */ 159 command = av; 160 setup_and_wait(trussinfo, command); 161 signal(SIGINT, SIG_IGN); 162 signal(SIGTERM, SIG_IGN); 163 signal(SIGQUIT, SIG_IGN); 164 } else { 165 sa.sa_handler = restore_proc; 166 sa.sa_flags = 0; 167 sigemptyset(&sa.sa_mask); 168 sigaction(SIGINT, &sa, NULL); 169 sigaction(SIGQUIT, &sa, NULL); 170 sigaction(SIGTERM, &sa, NULL); 171 start_tracing(trussinfo, pid); 172 } 173 174 /* 175 * At this point, if we started the process, it is stopped waiting to 176 * be woken up, either in exit() or in execve(). 177 */ 178 if (LIST_FIRST(&trussinfo->proclist)->abi == NULL) { 179 /* 180 * If we are not able to handle this ABI, detach from the 181 * process and exit. If we just created a new process to 182 * run a command, kill the new process rather than letting 183 * it run untraced. 184 */ 185 if (pid == 0) 186 kill(LIST_FIRST(&trussinfo->proclist)->pid, SIGKILL); 187 ptrace(PT_DETACH, LIST_FIRST(&trussinfo->proclist)->pid, NULL, 188 0); 189 return (1); 190 } 191 ptrace(PT_SYSCALL, LIST_FIRST(&trussinfo->proclist)->pid, (caddr_t)1, 192 0); 193 194 /* 195 * At this point, it's a simple loop, waiting for the process to 196 * stop, finding out why, printing out why, and then continuing it. 197 * All of the grunt work is done in the support routines. 198 */ 199 clock_gettime(CLOCK_REALTIME, &trussinfo->start_time); 200 201 eventloop(trussinfo); 202 203 if (trussinfo->flags & COUNTONLY) 204 print_summary(trussinfo); 205 206 fflush(trussinfo->outfile); 207 208 return (0); 209 } 210