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 * $FreeBSD: src/usr.sbin/watch/watch.c,v 1.18.2.3 2002/08/17 00:59:03 mikeh Exp $ 16 * $DragonFly: src/usr.sbin/watch/watch.c,v 1.5 2005/12/05 01:23:23 swildner Exp $ 17 */ 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 <locale.h> 29 #include <paths.h> 30 #include <signal.h> 31 #include <stdio.h> 32 #include <stdlib.h> 33 #include <string.h> 34 #include <sysexits.h> 35 #include <termcap.h> 36 #include <termios.h> 37 #include <time.h> 38 #include <unistd.h> 39 40 #define MSG_INIT "Snoop started." 41 #define MSG_OFLOW "Snoop stopped due to overflow. Reconnecting." 42 #define MSG_CLOSED "Snoop stopped due to tty close. Reconnecting." 43 #define MSG_CHANGE "Snoop device change by user request." 44 #define MSG_NOWRITE "Snoop device change due to write failure." 45 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); 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 dev_t snp_tty; 78 int std_in = 0, std_out = 1; 79 80 81 int clear_ok = 0; 82 struct termios otty; 83 char tbuf[1024], gbuf[1024]; 84 85 86 static void 87 clear(void) 88 { 89 if (clear_ok) 90 tputs(gbuf, 1, putchar); 91 fflush(stdout); 92 } 93 94 static void 95 timestamp(const char *buf) 96 { 97 time_t t; 98 char btmp[1024]; 99 clear(); 100 printf("\n---------------------------------------------\n"); 101 t = time(NULL); 102 strftime(btmp, 1024, "Time: %d %b %H:%M", localtime(&t)); 103 printf("%s\n", btmp); 104 printf("%s\n", buf); 105 printf("---------------------------------------------\n"); 106 fflush(stdout); 107 } 108 109 static void 110 set_tty(void) 111 { 112 struct termios ntty; 113 114 tcgetattr (std_in, &otty); 115 ntty = otty; 116 ntty.c_lflag &= ~ICANON; /* disable canonical operation */ 117 ntty.c_lflag &= ~ECHO; 118 #ifdef FLUSHO 119 ntty.c_lflag &= ~FLUSHO; 120 #endif 121 #ifdef PENDIN 122 ntty.c_lflag &= ~PENDIN; 123 #endif 124 #ifdef IEXTEN 125 ntty.c_lflag &= ~IEXTEN; 126 #endif 127 ntty.c_cc[VMIN] = 1; /* minimum of one character */ 128 ntty.c_cc[VTIME] = 0; /* timeout value */ 129 130 ntty.c_cc[VINTR] = 07; /* ^G */ 131 ntty.c_cc[VQUIT] = 07; /* ^G */ 132 tcsetattr (std_in, TCSANOW, &ntty); 133 } 134 135 static void 136 unset_tty(void) 137 { 138 tcsetattr (std_in, TCSANOW, &otty); 139 } 140 141 142 static void 143 fatal(int error, const char *buf) 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 char snp[] = {_PATH_DEV "snpX"}; 156 char c; 157 int f, mode; 158 159 if (opt_write) 160 mode = O_RDWR; 161 else 162 mode = O_RDONLY; 163 164 if (opt_snpdev == NULL) 165 for (c = '0'; c <= '9'; c++) { 166 snp[8] = c; 167 if ((f = open(snp, mode)) < 0) 168 continue; 169 return f; 170 } 171 else 172 if ((f = open(opt_snpdev, mode)) != -1) 173 return (f); 174 fatal(EX_OSFILE, "cannot open snoop device"); 175 return (0); 176 } 177 178 179 static void 180 cleanup(int signo __unused) 181 { 182 if (opt_timestamp) 183 timestamp("Logging Exited."); 184 close(snp_io); 185 unset_tty(); 186 exit(EX_OK); 187 } 188 189 190 static void 191 usage(void) 192 { 193 fprintf(stderr, "usage: watch [-ciotnW] [tty name]\n"); 194 exit(EX_USAGE); 195 } 196 197 static void 198 setup_scr(void) 199 { 200 char *cbuf = gbuf, *term; 201 if (!opt_interactive) 202 return; 203 if ((term = getenv("TERM"))) 204 if (tgetent(tbuf, term) == 1) 205 if (tgetstr("cl", &cbuf)) 206 clear_ok = 1; 207 set_tty(); 208 clear(); 209 } 210 211 static void 212 detach_snp(void) 213 { 214 dev_t dev; 215 216 dev = NODEV; 217 ioctl(snp_io, SNPSTTY, &dev); 218 } 219 220 static void 221 attach_snp(void) 222 { 223 if (ioctl(snp_io, SNPSTTY, &snp_tty) != 0) 224 fatal(EX_UNAVAILABLE, "cannot attach to tty"); 225 if (opt_timestamp) 226 timestamp("Logging Started."); 227 } 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 } 239 else { 240 if (strlen(name) == 2) 241 sprintf(buf, "%s%s", _PATH_TTY, name); 242 else 243 sprintf(buf, "%s%s", _PATH_DEV, name); 244 } 245 246 if (*name == '\0' || stat(buf, &sb) < 0) 247 fatal(EX_DATAERR, "bad device name"); 248 249 if ((sb.st_mode & S_IFMT) != S_IFCHR) 250 fatal(EX_DATAERR, "must be a character device"); 251 252 snp_tty = sb.st_rdev; 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 res, idata, rv; 288 size_t nread, b_size = MIN_SIZE; 289 char ch, *buf, chb[READB_LEN]; 290 fd_set fd_s; 291 292 setlocale(LC_TIME, ""); 293 294 if (isatty(std_out)) 295 opt_interactive = 1; 296 else 297 opt_interactive = 0; 298 299 300 while ((ch = getopt(ac, av, "Wciotnf:")) != -1) 301 switch (ch) { 302 case 'W': 303 opt_write = 1; 304 break; 305 case 'c': 306 opt_reconn_close = 1; 307 break; 308 case 'i': 309 opt_interactive = 1; 310 break; 311 case 'o': 312 opt_reconn_oflow = 1; 313 break; 314 case 't': 315 opt_timestamp = 1; 316 break; 317 case 'n': 318 opt_no_switch = 1; 319 break; 320 case 'f': 321 opt_snpdev = optarg; 322 break; 323 case '?': 324 default: 325 usage(); 326 } 327 328 if (modfind("snp") == -1) 329 if (kldload("snp") == -1 || modfind("snp") == -1) 330 warn("snp module not available"); 331 332 signal(SIGINT, cleanup); 333 334 setup_scr(); 335 snp_io = open_snp(); 336 337 if (*(av += optind) == NULL) { 338 if (opt_interactive && !opt_no_switch) 339 ask_dev(dev_name, MSG_INIT); 340 else 341 fatal(EX_DATAERR, "no device name given"); 342 } else 343 strncpy(dev_name, *av, DEV_NAME_LEN); 344 345 set_dev(dev_name); 346 347 if (!(buf = (char *) malloc(b_size))) 348 fatal(EX_UNAVAILABLE, "malloc failed"); 349 350 FD_ZERO(&fd_s); 351 352 while (1) { 353 if (opt_interactive) 354 FD_SET(std_in, &fd_s); 355 FD_SET(snp_io, &fd_s); 356 res = select(snp_io + 1, &fd_s, NULL, NULL, NULL); 357 if (opt_interactive && FD_ISSET(std_in, &fd_s)) { 358 359 if ((res = ioctl(std_in, FIONREAD, &nread)) != 0) 360 fatal(EX_OSERR, "ioctl(FIONREAD)"); 361 if (nread > READB_LEN) 362 nread = READB_LEN; 363 rv = read(std_in, chb, nread); 364 if (rv == -1 || (unsigned)rv != nread) 365 fatal(EX_IOERR, "read (stdin) failed"); 366 367 switch (chb[0]) { 368 case CHR_CLEAR: 369 clear(); 370 break; 371 case CHR_SWITCH: 372 if (!opt_no_switch) { 373 detach_snp(); 374 ask_dev(dev_name, MSG_CHANGE); 375 set_dev(dev_name); 376 break; 377 } 378 /* FALLTHROUGH */ 379 default: 380 if (opt_write) { 381 rv = write(snp_io, chb, nread); 382 if (rv == -1 || (unsigned)rv != nread) { 383 detach_snp(); 384 if (opt_no_switch) 385 fatal(EX_IOERR, "write failed"); 386 ask_dev(dev_name, MSG_NOWRITE); 387 set_dev(dev_name); 388 } 389 } 390 391 } 392 } 393 if (!FD_ISSET(snp_io, &fd_s)) 394 continue; 395 396 if ((res = ioctl(snp_io, FIONREAD, &idata)) != 0) 397 fatal(EX_OSERR, "ioctl(FIONREAD)"); 398 399 switch (idata) { 400 case SNP_OFLOW: 401 if (opt_reconn_oflow) 402 attach_snp(); 403 else if (opt_interactive && !opt_no_switch) { 404 ask_dev(dev_name, MSG_OFLOW); 405 set_dev(dev_name); 406 } else 407 cleanup(-1); 408 break; 409 case SNP_DETACH: 410 case SNP_TTYCLOSE: 411 if (opt_reconn_close) 412 attach_snp(); 413 else if (opt_interactive && !opt_no_switch) { 414 ask_dev(dev_name, MSG_CLOSED); 415 set_dev(dev_name); 416 } else 417 cleanup(-1); 418 break; 419 default: 420 nread = (unsigned)idata; 421 if (nread < (b_size / 2) && (b_size / 2) > MIN_SIZE) { 422 free(buf); 423 if (!(buf = (char *) malloc(b_size / 2))) 424 fatal(EX_UNAVAILABLE, "malloc failed"); 425 b_size = b_size / 2; 426 } 427 if (nread > b_size) { 428 b_size = (nread % 2) ? (nread + 1) : (nread); 429 free(buf); 430 if (!(buf = (char *) malloc(b_size))) 431 fatal(EX_UNAVAILABLE, "malloc failed"); 432 } 433 rv = read(snp_io, buf, nread); 434 if (rv == -1 || (unsigned)rv != nread) 435 fatal(EX_IOERR, "read failed"); 436 rv = write(std_out, buf, nread); 437 if (rv == -1 || (unsigned)rv != nread) 438 fatal(EX_IOERR, "write failed"); 439 } 440 } /* While */ 441 return(0); 442 } 443 444