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