1 /*- 2 * Copyright 1997 Sean Eric Fagan 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. All advertising materials mentioning features or use of this software 13 * must display the following acknowledgement: 14 * This product includes software developed by Sean Eric Fagan 15 * 4. Neither the name of the author may be used to endorse or promote 16 * products derived from this software without specific prior written 17 * permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 /* 36 * The main module for truss. Surprisingly simple, but, then, the other 37 * files handle the bulk of the work. And, of course, the kernel has to 38 * do a lot of the work :). 39 */ 40 41 #include <sys/ptrace.h> 42 43 #include <err.h> 44 #include <signal.h> 45 #include <stdbool.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <sysdecode.h> 49 #include <time.h> 50 #include <unistd.h> 51 52 #include "truss.h" 53 #include "extern.h" 54 #include "syscall.h" 55 56 static void 57 usage(void) 58 { 59 fprintf(stderr, "%s\n%s\n", 60 "usage: truss [-cfaedDHS] [-o file] [-s strsize] -p pid", 61 " truss [-cfaedDHS] [-o file] [-s strsize] command [args]"); 62 exit(1); 63 } 64 65 int 66 main(int ac, char **av) 67 { 68 struct sigaction sa; 69 struct trussinfo *trussinfo; 70 char *fname; 71 char **command; 72 pid_t pid; 73 int c; 74 75 fname = NULL; 76 77 /* Initialize the trussinfo struct */ 78 trussinfo = (struct trussinfo *)calloc(1, sizeof(struct trussinfo)); 79 if (trussinfo == NULL) 80 errx(1, "calloc() failed"); 81 82 pid = 0; 83 trussinfo->outfile = stderr; 84 trussinfo->strsize = 32; 85 trussinfo->curthread = NULL; 86 LIST_INIT(&trussinfo->proclist); 87 init_syscalls(); 88 while ((c = getopt(ac, av, "p:o:facedDs:SH")) != -1) { 89 switch (c) { 90 case 'p': /* specified pid */ 91 pid = atoi(optarg); 92 /* make sure i don't trace me */ 93 if (pid == getpid()) { 94 errx(2, "attempt to grab self."); 95 } 96 break; 97 case 'f': /* Follow fork()'s */ 98 trussinfo->flags |= FOLLOWFORKS; 99 break; 100 case 'a': /* Print execve() argument strings. */ 101 trussinfo->flags |= EXECVEARGS; 102 break; 103 case 'c': /* Count number of system calls and time. */ 104 trussinfo->flags |= (COUNTONLY | NOSIGS); 105 break; 106 case 'e': /* Print execve() environment strings. */ 107 trussinfo->flags |= EXECVEENVS; 108 break; 109 case 'd': /* Absolute timestamps */ 110 trussinfo->flags |= ABSOLUTETIMESTAMPS; 111 break; 112 case 'D': /* Relative timestamps */ 113 trussinfo->flags |= RELATIVETIMESTAMPS; 114 break; 115 case 'o': /* Specified output file */ 116 fname = optarg; 117 break; 118 case 's': /* Specified string size */ 119 trussinfo->strsize = atoi(optarg); 120 break; 121 case 'S': /* Don't trace signals */ 122 trussinfo->flags |= NOSIGS; 123 break; 124 case 'H': 125 trussinfo->flags |= DISPLAYTIDS; 126 break; 127 default: 128 usage(); 129 } 130 } 131 132 ac -= optind; av += optind; 133 if ((pid == 0 && ac == 0) || 134 (pid != 0 && ac != 0)) 135 usage(); 136 137 if (fname != NULL) { /* Use output file */ 138 /* 139 * Set close-on-exec ('e'), so that the output file is not 140 * shared with the traced process. 141 */ 142 if ((trussinfo->outfile = fopen(fname, "we")) == NULL) 143 err(1, "cannot open %s", fname); 144 } 145 146 /* 147 * If truss starts the process itself, it will ignore some signals -- 148 * they should be passed off to the process, which may or may not 149 * exit. If, however, we are examining an already-running process, 150 * then we restore the event mask on these same signals. 151 */ 152 if (pid == 0) { 153 /* Start a command ourselves */ 154 command = av; 155 setup_and_wait(trussinfo, command); 156 signal(SIGINT, SIG_IGN); 157 signal(SIGTERM, SIG_IGN); 158 signal(SIGQUIT, SIG_IGN); 159 } else { 160 sa.sa_handler = restore_proc; 161 sa.sa_flags = 0; 162 sigemptyset(&sa.sa_mask); 163 sigaction(SIGINT, &sa, NULL); 164 sigaction(SIGQUIT, &sa, NULL); 165 sigaction(SIGTERM, &sa, NULL); 166 start_tracing(trussinfo, pid); 167 } 168 169 /* 170 * At this point, if we started the process, it is stopped waiting to 171 * be woken up, either in exit() or in execve(). 172 */ 173 if (LIST_FIRST(&trussinfo->proclist)->abi == NULL) { 174 /* 175 * If we are not able to handle this ABI, detach from the 176 * process and exit. If we just created a new process to 177 * run a command, kill the new process rather than letting 178 * it run untraced. 179 */ 180 if (pid == 0) 181 kill(LIST_FIRST(&trussinfo->proclist)->pid, SIGKILL); 182 ptrace(PT_DETACH, LIST_FIRST(&trussinfo->proclist)->pid, NULL, 183 0); 184 return (1); 185 } 186 ptrace(PT_SYSCALL, LIST_FIRST(&trussinfo->proclist)->pid, (caddr_t)1, 187 0); 188 189 /* 190 * At this point, it's a simple loop, waiting for the process to 191 * stop, finding out why, printing out why, and then continuing it. 192 * All of the grunt work is done in the support routines. 193 */ 194 clock_gettime(CLOCK_REALTIME, &trussinfo->start_time); 195 196 eventloop(trussinfo); 197 198 if (trussinfo->flags & COUNTONLY) 199 print_summary(trussinfo); 200 201 fflush(trussinfo->outfile); 202 203 return (0); 204 } 205