1 /* 2 * Copyright (c) 1995 Ugen J.S.Antsilevich 3 * 4 * Redistribution and use in source forms, with and without modification, 5 * are permitted provided that this entire comment appears intact. 6 * 7 * Redistribution in binary form may occur without any restrictions. 8 * Obviously, it would be nice if you gave credit where credit is due 9 * but requiring it would be too onerous. 10 * 11 * This software is provided ``AS IS'' without any warranties of any kind. 12 * 13 * Snoop stuff. 14 */ 15 16 #include <sys/cdefs.h> 17 __FBSDID("$FreeBSD$"); 18 19 #include <sys/param.h> 20 #include <sys/fcntl.h> 21 #include <sys/filio.h> 22 #include <sys/snoop.h> 23 #include <sys/stat.h> 24 #include <sys/linker.h> 25 #include <sys/module.h> 26 27 #include <err.h> 28 #include <errno.h> 29 #include <locale.h> 30 #include <paths.h> 31 #include <signal.h> 32 #include <stdio.h> 33 #include <stdlib.h> 34 #include <string.h> 35 #include <sysexits.h> 36 #include <termcap.h> 37 #include <termios.h> 38 #include <time.h> 39 #include <unistd.h> 40 41 #define MSG_INIT "Snoop started." 42 #define MSG_OFLOW "Snoop stopped due to overflow. Reconnecting." 43 #define MSG_CLOSED "Snoop stopped due to tty close. Reconnecting." 44 #define MSG_CHANGE "Snoop device change by user request." 45 #define MSG_NOWRITE "Snoop device change due to write failure." 46 47 #define DEV_NAME_LEN 1024 /* for /dev/ttyXX++ */ 48 #define MIN_SIZE 256 49 50 #define CHR_SWITCH 24 /* Ctrl+X */ 51 #define CHR_CLEAR 23 /* Ctrl+V */ 52 53 static void clear(void); 54 static void timestamp(const char *); 55 static void set_tty(void); 56 static void unset_tty(void); 57 static void fatal(int, const char *); 58 static int open_snp(void); 59 static void cleanup(int); 60 static void usage(void) __dead2; 61 static void setup_scr(void); 62 static void attach_snp(void); 63 static void detach_snp(void); 64 static void set_dev(const char *); 65 static void ask_dev(char *, const char *); 66 67 int opt_reconn_close = 0; 68 int opt_reconn_oflow = 0; 69 int opt_interactive = 1; 70 int opt_timestamp = 0; 71 int opt_write = 0; 72 int opt_no_switch = 0; 73 const char *opt_snpdev; 74 75 char dev_name[DEV_NAME_LEN]; 76 int snp_io; 77 int std_in = 0, std_out = 1; 78 79 int clear_ok = 0; 80 struct termios otty; 81 char tbuf[1024], gbuf[1024]; 82 83 static void 84 clear(void) 85 { 86 87 if (clear_ok) 88 tputs(gbuf, 1, putchar); 89 fflush(stdout); 90 } 91 92 static void 93 timestamp(const char *buf) 94 { 95 time_t t; 96 char btmp[1024]; 97 98 clear(); 99 printf("\n---------------------------------------------\n"); 100 t = time(NULL); 101 strftime(btmp, 1024, "Time: %d %b %H:%M", localtime(&t)); 102 printf("%s\n", btmp); 103 printf("%s\n", buf); 104 printf("---------------------------------------------\n"); 105 fflush(stdout); 106 } 107 108 static void 109 set_tty(void) 110 { 111 struct termios ntty; 112 113 tcgetattr(std_in, &otty); 114 ntty = otty; 115 ntty.c_lflag &= ~ICANON; /* disable canonical operation */ 116 ntty.c_lflag &= ~ECHO; 117 #ifdef FLUSHO 118 ntty.c_lflag &= ~FLUSHO; 119 #endif 120 #ifdef PENDIN 121 ntty.c_lflag &= ~PENDIN; 122 #endif 123 #ifdef IEXTEN 124 ntty.c_lflag &= ~IEXTEN; 125 #endif 126 ntty.c_cc[VMIN] = 1; /* minimum of one character */ 127 ntty.c_cc[VTIME] = 0; /* timeout value */ 128 129 ntty.c_cc[VINTR] = 07; /* ^G */ 130 ntty.c_cc[VQUIT] = 07; /* ^G */ 131 tcsetattr(std_in, TCSANOW, &ntty); 132 } 133 134 static void 135 unset_tty(void) 136 { 137 138 tcsetattr(std_in, TCSANOW, &otty); 139 } 140 141 static void 142 fatal(int error, const char *buf) 143 { 144 145 unset_tty(); 146 if (buf) 147 errx(error, "fatal: %s", buf); 148 else 149 exit(error); 150 } 151 152 static int 153 open_snp(void) 154 { 155 int f, mode; 156 157 if (opt_write) 158 mode = O_RDWR; 159 else 160 mode = O_RDONLY; 161 162 if (opt_snpdev == NULL) 163 f = open(_PATH_DEV "snp", mode); 164 else 165 f = open(opt_snpdev, mode); 166 if (f == -1) 167 fatal(EX_OSFILE, "cannot open snoop device"); 168 169 return (f); 170 } 171 172 static void 173 cleanup(int signo __unused) 174 { 175 176 if (opt_timestamp) 177 timestamp("Logging Exited."); 178 close(snp_io); 179 unset_tty(); 180 exit(EX_OK); 181 } 182 183 static void 184 usage(void) 185 { 186 187 fprintf(stderr, "usage: watch [-ciotnW] [tty name]\n"); 188 exit(EX_USAGE); 189 } 190 191 static void 192 setup_scr(void) 193 { 194 char *cbuf = gbuf, *term; 195 196 if (!opt_interactive) 197 return; 198 if ((term = getenv("TERM"))) 199 if (tgetent(tbuf, term) == 1) 200 if (tgetstr("cl", &cbuf)) 201 clear_ok = 1; 202 set_tty(); 203 clear(); 204 } 205 206 static void 207 detach_snp(void) 208 { 209 int fd; 210 211 fd = -1; 212 ioctl(snp_io, SNPSTTY, &fd); 213 } 214 215 static void 216 attach_snp(void) 217 { 218 int snp_tty; 219 220 snp_tty = open(dev_name, O_RDONLY | O_NONBLOCK); 221 if (snp_tty < 0) 222 fatal(EX_DATAERR, "can't open device"); 223 if (ioctl(snp_io, SNPSTTY, &snp_tty) != 0) 224 fatal(EX_UNAVAILABLE, "cannot attach to tty"); 225 close(snp_tty); 226 if (opt_timestamp) 227 timestamp("Logging Started."); 228 } 229 230 static void 231 set_dev(const char *name) 232 { 233 char buf[DEV_NAME_LEN]; 234 struct stat sb; 235 236 if (strlen(name) > 5 && !strncmp(name, _PATH_DEV, sizeof _PATH_DEV - 1)) { 237 snprintf(buf, sizeof buf, "%s", name); 238 } else { 239 if (strlen(name) == 2) 240 sprintf(buf, "%s%s", _PATH_TTY, name); 241 else 242 sprintf(buf, "%s%s", _PATH_DEV, name); 243 } 244 245 if (*name == '\0' || stat(buf, &sb) < 0) 246 fatal(EX_DATAERR, "bad device name"); 247 248 if ((sb.st_mode & S_IFMT) != S_IFCHR) 249 fatal(EX_DATAERR, "must be a character device"); 250 251 strncpy(dev_name, buf, DEV_NAME_LEN); 252 253 attach_snp(); 254 } 255 256 void 257 ask_dev(char *dbuf, const char *msg) 258 { 259 char buf[DEV_NAME_LEN]; 260 int len; 261 262 clear(); 263 unset_tty(); 264 265 if (msg) 266 printf("%s\n", msg); 267 if (dbuf) 268 printf("Enter device name [%s]:", dbuf); 269 else 270 printf("Enter device name:"); 271 272 if (fgets(buf, DEV_NAME_LEN - 1, stdin)) { 273 len = strlen(buf); 274 if (buf[len - 1] == '\n') 275 buf[len - 1] = '\0'; 276 if (buf[0] != '\0' && buf[0] != ' ') 277 strcpy(dbuf, buf); 278 } 279 set_tty(); 280 } 281 282 #define READB_LEN 5 283 284 int 285 main(int ac, char *av[]) 286 { 287 int ch, res, rv, nread; 288 size_t b_size = MIN_SIZE; 289 char *buf, chb[READB_LEN]; 290 fd_set fd_s; 291 292 (void) setlocale(LC_TIME, ""); 293 294 if (isatty(std_out)) 295 opt_interactive = 1; 296 else 297 opt_interactive = 0; 298 299 while ((ch = getopt(ac, av, "Wciotnf:")) != -1) 300 switch (ch) { 301 case 'W': 302 opt_write = 1; 303 break; 304 case 'c': 305 opt_reconn_close = 1; 306 break; 307 case 'i': 308 opt_interactive = 1; 309 break; 310 case 'o': 311 opt_reconn_oflow = 1; 312 break; 313 case 't': 314 opt_timestamp = 1; 315 break; 316 case 'n': 317 opt_no_switch = 1; 318 break; 319 case 'f': 320 opt_snpdev = optarg; 321 break; 322 case '?': 323 default: 324 usage(); 325 } 326 327 if (modfind("snp") == -1) 328 if (kldload("snp") == -1 || modfind("snp") == -1) 329 warn("snp module not available"); 330 331 signal(SIGINT, cleanup); 332 333 snp_io = open_snp(); 334 setup_scr(); 335 336 if (*(av += optind) == NULL) { 337 if (opt_interactive && !opt_no_switch) 338 ask_dev(dev_name, MSG_INIT); 339 else 340 fatal(EX_DATAERR, "no device name given"); 341 } else 342 strncpy(dev_name, *av, DEV_NAME_LEN); 343 344 set_dev(dev_name); 345 346 if (!(buf = (char *) malloc(b_size))) 347 fatal(EX_UNAVAILABLE, "malloc failed"); 348 349 FD_ZERO(&fd_s); 350 351 for (;;) { 352 if (opt_interactive) 353 FD_SET(std_in, &fd_s); 354 FD_SET(snp_io, &fd_s); 355 res = select(snp_io + 1, &fd_s, NULL, NULL, NULL); 356 if (opt_interactive && FD_ISSET(std_in, &fd_s)) { 357 358 if ((res = ioctl(std_in, FIONREAD, &nread)) != 0) 359 fatal(EX_OSERR, "ioctl(FIONREAD)"); 360 if (nread > READB_LEN) 361 nread = READB_LEN; 362 rv = read(std_in, chb, nread); 363 if (rv == -1 || rv != nread) 364 fatal(EX_IOERR, "read (stdin) failed"); 365 366 switch (chb[0]) { 367 case CHR_CLEAR: 368 clear(); 369 break; 370 case CHR_SWITCH: 371 if (!opt_no_switch) { 372 detach_snp(); 373 ask_dev(dev_name, MSG_CHANGE); 374 set_dev(dev_name); 375 break; 376 } 377 default: 378 if (opt_write) { 379 rv = write(snp_io, chb, nread); 380 if (rv == -1 || rv != nread) { 381 detach_snp(); 382 if (opt_no_switch) 383 fatal(EX_IOERR, 384 "write failed"); 385 ask_dev(dev_name, MSG_NOWRITE); 386 set_dev(dev_name); 387 } 388 } 389 390 } 391 } 392 if (!FD_ISSET(snp_io, &fd_s)) 393 continue; 394 395 if ((res = ioctl(snp_io, FIONREAD, &nread)) != 0) 396 fatal(EX_OSERR, "ioctl(FIONREAD)"); 397 398 switch (nread) { 399 case SNP_OFLOW: 400 if (opt_reconn_oflow) 401 attach_snp(); 402 else if (opt_interactive && !opt_no_switch) { 403 ask_dev(dev_name, MSG_OFLOW); 404 set_dev(dev_name); 405 } else 406 cleanup(-1); 407 break; 408 case SNP_DETACH: 409 case SNP_TTYCLOSE: 410 if (opt_reconn_close) 411 attach_snp(); 412 else if (opt_interactive && !opt_no_switch) { 413 ask_dev(dev_name, MSG_CLOSED); 414 set_dev(dev_name); 415 } else 416 cleanup(-1); 417 break; 418 default: 419 if (nread < (b_size / 2) && (b_size / 2) > MIN_SIZE) { 420 free(buf); 421 if (!(buf = (char *) malloc(b_size / 2))) 422 fatal(EX_UNAVAILABLE, "malloc failed"); 423 b_size = b_size / 2; 424 } 425 if (nread > b_size) { 426 b_size = (nread % 2) ? (nread + 1) : (nread); 427 free(buf); 428 if (!(buf = (char *) malloc(b_size))) 429 fatal(EX_UNAVAILABLE, "malloc failed"); 430 } 431 rv = read(snp_io, buf, nread); 432 if (rv == -1 || rv != nread) 433 fatal(EX_IOERR, "read failed"); 434 rv = write(std_out, buf, nread); 435 if (rv == -1 || rv != nread) 436 fatal(EX_IOERR, "write failed"); 437 } 438 } /* While */ 439 return(0); 440 } 441