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 <stdio.h> 46 #include <stdlib.h> 47 #include <sysdecode.h> 48 #include <time.h> 49 #include <unistd.h> 50 51 #include "truss.h" 52 #include "extern.h" 53 #include "syscall.h" 54 55 static void 56 usage(void) 57 { 58 fprintf(stderr, "%s\n%s\n", 59 "usage: truss [-cfaedDS] [-o file] [-s strsize] -p pid", 60 " truss [-cfaedDS] [-o file] [-s strsize] command [args]"); 61 exit(1); 62 } 63 64 char * 65 strsig(int sig) 66 { 67 static char tmp[64]; 68 69 if (sig > 0 && sig < NSIG) { 70 snprintf(tmp, sizeof(tmp), "SIG%s", sys_signame[sig]); 71 return (tmp); 72 } 73 return (NULL); 74 } 75 76 int 77 main(int ac, char **av) 78 { 79 struct sigaction sa; 80 struct trussinfo *trussinfo; 81 char *fname; 82 char **command; 83 pid_t pid; 84 int c; 85 86 fname = NULL; 87 88 /* Initialize the trussinfo struct */ 89 trussinfo = (struct trussinfo *)calloc(1, sizeof(struct trussinfo)); 90 if (trussinfo == NULL) 91 errx(1, "calloc() failed"); 92 93 pid = 0; 94 trussinfo->outfile = stderr; 95 trussinfo->strsize = 32; 96 trussinfo->curthread = NULL; 97 LIST_INIT(&trussinfo->proclist); 98 init_syscalls(); 99 while ((c = getopt(ac, av, "p:o:facedDs:S")) != -1) { 100 switch (c) { 101 case 'p': /* specified pid */ 102 pid = atoi(optarg); 103 /* make sure i don't trace me */ 104 if (pid == getpid()) { 105 errx(2, "attempt to grab self."); 106 } 107 break; 108 case 'f': /* Follow fork()'s */ 109 trussinfo->flags |= FOLLOWFORKS; 110 break; 111 case 'a': /* Print execve() argument strings. */ 112 trussinfo->flags |= EXECVEARGS; 113 break; 114 case 'c': /* Count number of system calls and time. */ 115 trussinfo->flags |= (COUNTONLY | NOSIGS); 116 break; 117 case 'e': /* Print execve() environment strings. */ 118 trussinfo->flags |= EXECVEENVS; 119 break; 120 case 'd': /* Absolute timestamps */ 121 trussinfo->flags |= ABSOLUTETIMESTAMPS; 122 break; 123 case 'D': /* Relative timestamps */ 124 trussinfo->flags |= RELATIVETIMESTAMPS; 125 break; 126 case 'o': /* Specified output file */ 127 fname = optarg; 128 break; 129 case 's': /* Specified string size */ 130 trussinfo->strsize = atoi(optarg); 131 break; 132 case 'S': /* Don't trace signals */ 133 trussinfo->flags |= NOSIGS; 134 break; 135 default: 136 usage(); 137 } 138 } 139 140 ac -= optind; av += optind; 141 if ((pid == 0 && ac == 0) || 142 (pid != 0 && ac != 0)) 143 usage(); 144 145 if (fname != NULL) { /* Use output file */ 146 /* 147 * Set close-on-exec ('e'), so that the output file is not 148 * shared with the traced process. 149 */ 150 if ((trussinfo->outfile = fopen(fname, "we")) == NULL) 151 err(1, "cannot open %s", fname); 152 } 153 154 /* 155 * If truss starts the process itself, it will ignore some signals -- 156 * they should be passed off to the process, which may or may not 157 * exit. If, however, we are examining an already-running process, 158 * then we restore the event mask on these same signals. 159 */ 160 if (pid == 0) { 161 /* Start a command ourselves */ 162 command = av; 163 setup_and_wait(trussinfo, command); 164 signal(SIGINT, SIG_IGN); 165 signal(SIGTERM, SIG_IGN); 166 signal(SIGQUIT, SIG_IGN); 167 } else { 168 sa.sa_handler = restore_proc; 169 sa.sa_flags = 0; 170 sigemptyset(&sa.sa_mask); 171 sigaction(SIGINT, &sa, NULL); 172 sigaction(SIGQUIT, &sa, NULL); 173 sigaction(SIGTERM, &sa, NULL); 174 start_tracing(trussinfo, pid); 175 } 176 177 /* 178 * At this point, if we started the process, it is stopped waiting to 179 * be woken up, either in exit() or in execve(). 180 */ 181 if (LIST_FIRST(&trussinfo->proclist)->abi == NULL) { 182 /* 183 * If we are not able to handle this ABI, detach from the 184 * process and exit. If we just created a new process to 185 * run a command, kill the new process rather than letting 186 * it run untraced. 187 */ 188 if (pid == 0) 189 kill(LIST_FIRST(&trussinfo->proclist)->pid, SIGKILL); 190 ptrace(PT_DETACH, LIST_FIRST(&trussinfo->proclist)->pid, NULL, 191 0); 192 return (1); 193 } 194 ptrace(PT_SYSCALL, LIST_FIRST(&trussinfo->proclist)->pid, (caddr_t)1, 195 0); 196 197 /* 198 * At this point, it's a simple loop, waiting for the process to 199 * stop, finding out why, printing out why, and then continuing it. 200 * All of the grunt work is done in the support routines. 201 */ 202 clock_gettime(CLOCK_REALTIME, &trussinfo->start_time); 203 204 eventloop(trussinfo); 205 206 if (trussinfo->flags & COUNTONLY) 207 print_summary(trussinfo); 208 209 fflush(trussinfo->outfile); 210 211 return (0); 212 } 213