Super User's BSD Cross Reference: /FreeBSD/usr.sbin/watch/watch.c

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 ntty = otty;
114 ntty.c_lflag &= ~ICANON; /* disable canonical operation */
115 ntty.c_lflag &= ~ECHO;
116#ifdef FLUSHO
117 ntty.c_lflag &= ~FLUSHO;
118#endif
119#ifdef PENDIN
120 ntty.c_lflag &= ~PENDIN;
121#endif
122#ifdef IEXTEN
123 ntty.c_lflag &= ~IEXTEN;
124#endif
125 ntty.c_cc[VMIN] = 1; /* minimum of one character */
126 ntty.c_cc[VTIME] = 0; /* timeout value */
127
128 ntty.c_cc[VINTR] = 07; /* ^G */
129 ntty.c_cc[VQUIT] = 07; /* ^G */
130 tcsetattr(std_in, TCSANOW, &ntty);
131}
132
133 static void
134 unset_tty(void)
135{
136
137 tcsetattr(std_in, TCSANOW, &otty);
138}
139
140 static void
141 fatal(int error, const char *buf)
142{
143
144 unset_tty();
145 if (buf)
146 errx(error, "fatal: %s", buf);
147 else
148 exit(error);
149}
150
151 static int
152 open_snp(void)
153{
154 int f, mode;
155
156 if (opt_write)
157 mode = O_RDWR;
158 else
159 mode = O_RDONLY;
160
161 if (opt_snpdev == NULL)
162 f = open(_PATH_DEV "snp", mode);
163 else
164 f = open(opt_snpdev, mode);
165 if (f == -1)
166 fatal(EX_OSFILE, "cannot open snoop device");
167
168 return (f);
169}
170
171 static void
172 cleanup(int signo __unused)
173{
174
175 if (opt_timestamp)
176 timestamp("Logging Exited.");
177 close(snp_io);
178 unset_tty();
179 exit(EX_OK);
180}
181
182 static void
183 usage(void)
184{
185
186 fprintf(stderr, "usage: watch [-ciotnW] [tty name]\n");
187 exit(EX_USAGE);
188}
189
190 static void
191 setup_scr(void)
192{
193 char *cbuf = gbuf, *term;
194
195 if (!opt_interactive)
196 return;
197 if ((term = getenv("TERM")))
198 if (tgetent(tbuf, term) == 1)
199 if (tgetstr("cl", &cbuf))
200 clear_ok = 1;
201 set_tty();
202 clear();
203}
204
205 static void
206 detach_snp(void)
207{
208 int fd;
209
210 fd = -1;
211 ioctl(snp_io, SNPSTTY, &fd);
212}
213
214 static void
215 attach_snp(void)
216{
217 int snp_tty;
218
219 snp_tty = open(dev_name, O_RDONLY | O_NONBLOCK);
220 if (snp_tty < 0)
221 fatal(EX_DATAERR, "can't open device");
222 if (ioctl(snp_io, SNPSTTY, &snp_tty) != 0)
223 fatal(EX_UNAVAILABLE, "cannot attach to tty");
224 close(snp_tty);
225 if (opt_timestamp)
226 timestamp("Logging Started.");
227}
228
229 static void
230 set_dev(const char *name)
231{
232 char buf[DEV_NAME_LEN];
233 struct stat sb;
234
235 if (strlen(name) > 5 && !strncmp(name, _PATH_DEV, sizeof _PATH_DEV - 1)) {
236 snprintf(buf, sizeof buf, "%s", name);
237 } else {
238 if (strlen(name) == 2)
239 sprintf(buf, "%s%s", _PATH_TTY, name);
240 else
241 sprintf(buf, "%s%s", _PATH_DEV, name);
242 }
243
244 if (*name == '0円' || stat(buf, &sb) < 0)
245 fatal(EX_DATAERR, "bad device name");
246
247 if ((sb.st_mode & S_IFMT) != S_IFCHR)
248 fatal(EX_DATAERR, "must be a character device");
249
250 strlcpy(dev_name, buf, sizeof(dev_name));
251
252 attach_snp();
253}
254
255 void
256 ask_dev(char *dbuf, const char *msg)
257{
258 char buf[DEV_NAME_LEN];
259 int len;
260
261 clear();
262 unset_tty();
263
264 if (msg)
265 printf("%s\n", msg);
266 if (dbuf)
267 printf("Enter device name [%s]:", dbuf);
268 else
269 printf("Enter device name:");
270
271 if (fgets(buf, DEV_NAME_LEN - 1, stdin)) {
272 len = strlen(buf);
273 if (buf[len - 1] == '\n')
274 buf[len - 1] = '0円';
275 if (buf[0] != '0円' && buf[0] != ' ')
276 strcpy(dbuf, buf);
277 }
278 set_tty();
279}
280
281#define READB_LEN 5
282
283 int
284 main(int ac, char *av[])
285{
286 int ch, res, rv, nread;
287 size_t b_size = MIN_SIZE;
288 char *buf, chb[READB_LEN];
289 fd_set fd_s;
290
291 (void) setlocale(LC_TIME, "");
292
293 if (isatty(std_out))
294 opt_interactive = 1;
295 else
296 opt_interactive = 0;
297
298 while ((ch = getopt(ac, av, "Wciotnf:")) != -1)
299 switch (ch) {
300 case 'W':
301 opt_write = 1;
302 break;
303 case 'c':
304 opt_reconn_close = 1;
305 break;
306 case 'i':
307 opt_interactive = 1;
308 break;
309 case 'o':
310 opt_reconn_oflow = 1;
311 break;
312 case 't':
313 opt_timestamp = 1;
314 break;
315 case 'n':
316 opt_no_switch = 1;
317 break;
318 case 'f':
319 opt_snpdev = optarg;
320 break;
321 case '?':
322 default:
323 usage();
324 }
325
326 tcgetattr(std_in, &otty);
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 snp_io = open_snp();
335 setup_scr();
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 strlcpy(dev_name, *av, sizeof(dev_name));
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 for (;;) {
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 || 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 default:
379 if (opt_write) {
380 rv = write(snp_io, chb, nread);
381 if (rv == -1 || rv != nread) {
382 detach_snp();
383 if (opt_no_switch)
384 fatal(EX_IOERR,
385 "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, &nread)) != 0)
397 fatal(EX_OSERR, "ioctl(FIONREAD)");
398
399 switch (nread) {
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 if (nread < (b_size / 2) && (b_size / 2) > MIN_SIZE) {
421 free(buf);
422 if (!(buf = (char *) malloc(b_size / 2)))
423 fatal(EX_UNAVAILABLE, "malloc failed");
424 b_size = b_size / 2;
425 }
426 if (nread > b_size) {
427 b_size = (nread % 2) ? (nread + 1) : (nread);
428 free(buf);
429 if (!(buf = (char *) malloc(b_size)))
430 fatal(EX_UNAVAILABLE, "malloc failed");
431 }
432 rv = read(snp_io, buf, nread);
433 if (rv == -1 || rv != nread)
434 fatal(EX_IOERR, "read failed");
435 rv = write(std_out, buf, nread);
436 if (rv == -1 || rv != nread)
437 fatal(EX_IOERR, "write failed");
438 }
439 } /* While */
440 return(0);
441}
442 

AltStyle によって変換されたページ (->オリジナル) /