xref: /netbsd-src/usr.bin/script/script.c (revision 7d62b00eb9ad855ffcd7da46b41e23feb5476fac)
1 /*	$NetBSD: script.c,v 1.33 2022/02/13 19:40:14 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1992, 1993\
35  The Regents of the University of California.  All rights reserved.");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)script.c	8.1 (Berkeley) 6/6/93";
41 #endif
42 __RCSID("$NetBSD: script.c,v 1.33 2022/02/13 19:40:14 christos Exp $");
43 #endif /* not lint */
44 
45 #include <sys/types.h>
46 #include <sys/wait.h>
47 #include <sys/stat.h>
48 #include <sys/ioctl.h>
49 #include <sys/time.h>
50 #include <sys/param.h>
51 #include <sys/uio.h>
52 
53 #include <err.h>
54 #include <errno.h>
55 #include <fcntl.h>
56 #include <paths.h>
57 #include <signal.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <termios.h>
62 #include <time.h>
63 #include <tzfile.h>
64 #include <unistd.h>
65 #include <util.h>
66 
67 #define	DEF_BUF	65536
68 
69 struct stamp {
70 	uint64_t scr_len;	/* amount of data */
71 	uint64_t scr_sec;	/* time it arrived in seconds... */
72 	uint32_t scr_usec;	/* ...and microseconds */
73 	uint32_t scr_direction;	/* 'i', 'o', etc (also indicates endianness) */
74 };
75 
76 static FILE	*fscript;
77 static int	master, slave;
78 static int	child, subchild;
79 static size_t	outcc;
80 static int	usesleep, rawout;
81 static int	quiet, flush;
82 static const char *fname;
83 
84 static volatile	sig_atomic_t die = 0;	/* exit if 1 */
85 static int	cstat = EXIT_SUCCESS;	/* cmd. exit status */
86 static int	eflag;
87 static int	isterm;
88 static struct	termios tt;
89 
90 __dead static void	done(int);
91 __dead static void	doshell(const char *);
92 __dead static void	fail(void);
93 static sig_t	xsignal(int, sig_t);
94 __dead static void	dooutput(void);
95 static void	finish(int);
96 static void	scriptflush(int);
97 static void	record(FILE *, char *, size_t, int);
98 static void	consume(FILE *, off_t, char *, int);
99 __dead static void	playback(FILE *);
100 
101 int
102 main(int argc, char *argv[])
103 {
104 	ssize_t scc;
105 	size_t cc;
106 	struct termios rtt;
107 	struct winsize win;
108 	int aflg, pflg, ch;
109 	char ibuf[BUFSIZ];
110 	const char *command;
111 
112 	aflg = 0;
113 	pflg = 0;
114 	usesleep = 1;
115 	rawout = 0;
116 	quiet = 0;
117 	flush = 0;
118 	command = NULL;
119 	while ((ch = getopt(argc, argv, "ac:defpqr")) != -1)
120 		switch(ch) {
121 		case 'a':
122 			aflg = 1;
123 			break;
124 		case 'c':
125 			command = optarg;
126 			break;
127 		case 'd':
128 			usesleep = 0;
129 			break;
130 		case 'e':
131 			eflag = 1;
132 			break;
133 		case 'f':
134 			flush = 1;
135 			break;
136 		case 'p':
137 			pflg = 1;
138 			break;
139 		case 'q':
140 			quiet = 1;
141 			break;
142 		case 'r':
143 			rawout = 1;
144 			break;
145 		case '?':
146 		default:
147 			(void)fprintf(stderr,
148 			    "Usage: %s [-c <command>][-adefpqr] [file]\n",
149 			    getprogname());
150 			exit(EXIT_FAILURE);
151 		}
152 	argc -= optind;
153 	argv += optind;
154 
155 	if (argc > 0)
156 		fname = argv[0];
157 	else
158 		fname = "typescript";
159 
160 	if ((fscript = fopen(fname, pflg ? "r" : aflg ? "a" : "w")) == NULL)
161 		err(EXIT_FAILURE, "fopen %s", fname);
162 
163 	if (pflg)
164 		playback(fscript);
165 
166 	if (tcgetattr(STDIN_FILENO, &tt) == -1 ||
167 	    ioctl(STDIN_FILENO, TIOCGWINSZ, &win) == -1) {
168 		if (errno != ENOTTY) /* For debugger. */
169 			err(EXIT_FAILURE, "tcgetattr/ioctl");
170 		if (openpty(&master, &slave, NULL, NULL, NULL) == -1)
171 			err(EXIT_FAILURE, "openpty");
172 	} else {
173 		if (openpty(&master, &slave, NULL, &tt, &win) == -1)
174 			err(EXIT_FAILURE, "openpty");
175 		isterm = 1;
176 	}
177 
178 	if (!quiet)
179 		(void)printf("Script started, output file is %s\n", fname);
180 
181 	if (isterm) {
182 		rtt = tt;
183 		cfmakeraw(&rtt);
184 		rtt.c_lflag &= ~ECHO;
185 		(void)tcsetattr(STDIN_FILENO, TCSAFLUSH, &rtt);
186 	}
187 
188 	(void)xsignal(SIGCHLD, finish);
189 	child = fork();
190 	if (child == -1) {
191 		warn("fork");
192 		fail();
193 	}
194 	if (child == 0) {
195 		subchild = child = fork();
196 		if (child == -1) {
197 			warn("fork");
198 			fail();
199 		}
200 		if (child)
201 			dooutput();
202 		else
203 			doshell(command);
204 	}
205 
206 	if (!rawout)
207 		(void)fclose(fscript);
208 	while (!die && (scc = read(STDIN_FILENO, ibuf, BUFSIZ)) > 0) {
209 		cc = (size_t)scc;
210 		if (rawout)
211 			record(fscript, ibuf, cc, 'i');
212 		(void)write(master, ibuf, cc);
213 	}
214 	done(cstat);
215 }
216 
217 /**
218  * wrapper around sigaction() because we want POSIX semantics:
219  * no auto-restarting of interrupted slow syscalls.
220  */
221 static sig_t
222 xsignal(int signo, sig_t handler)
223 {
224 	struct sigaction sa, osa;
225 
226 	sa.sa_handler = handler;
227 	sa.sa_flags = 0;
228 	sigemptyset(&sa.sa_mask);
229 	if (sigaction(signo, &sa, &osa) == -1)
230 		return SIG_ERR;
231 	return osa.sa_handler;
232 }
233 
234 static int
235 getshellstatus(int status)
236 {
237 	if (WIFEXITED(status))
238 		return WEXITSTATUS(status);
239 	if (WIFSIGNALED(status))
240 		return 128 + WTERMSIG(status);
241 	return EXIT_FAILURE;
242 }
243 
244 static void
245 finish(int signo)
246 {
247 	int pid, status;
248 
249 	die = 0;
250 	while ((pid = wait(&status)) > 0)
251 		if (pid == child) {
252 			die = 1;
253 		}
254 
255 	if (!die)
256 		return;
257 	done(eflag ? getshellstatus(status) : EXIT_SUCCESS);
258 }
259 
260 static void
261 dooutput(void)
262 {
263 	struct itimerval value;
264 	ssize_t scc;
265 	size_t cc;
266 	time_t tvec;
267 	char obuf[BUFSIZ];
268 
269 	(void)close(STDIN_FILENO);
270 	tvec = time(NULL);
271 	if (rawout)
272 		record(fscript, NULL, 0, 's');
273 	else if (!quiet)
274 		(void)fprintf(fscript, "Script started on %s", ctime(&tvec));
275 
276 	(void)signal(SIGALRM, scriptflush);
277 	value.it_interval.tv_sec = SECSPERMIN / 2;
278 	value.it_interval.tv_usec = 0;
279 	value.it_value = value.it_interval;
280 	(void)setitimer(ITIMER_REAL, &value, NULL);
281 	for (;;) {
282 		scc = read(master, obuf, sizeof(obuf));
283 		if (scc <= 0)
284 			break;
285 		cc = (size_t)scc;
286 		(void)write(STDOUT_FILENO, obuf, cc);
287 		if (rawout)
288 			record(fscript, obuf, cc, 'o');
289 		else
290 			(void)fwrite(obuf, 1, cc, fscript);
291 		outcc += cc;
292 		if (flush)
293 			(void)fflush(fscript);
294 	}
295 	done(cstat);
296 }
297 
298 static void
299 scriptflush(int signo)
300 {
301 	if (outcc) {
302 		(void)fflush(fscript);
303 		outcc = 0;
304 	}
305 }
306 
307 static void
308 doshell(const char *command)
309 {
310 	const char *shell;
311 
312 	(void)close(master);
313 	(void)fclose(fscript);
314 	login_tty(slave);
315 	if (command == NULL) {
316 		shell = getenv("SHELL");
317 		if (shell == NULL)
318 			shell = _PATH_BSHELL;
319 		execl(shell, shell, "-i", NULL);
320 		warn("execl `%s'", shell);
321 	} else {
322 		int ret = system(command);
323 		if (ret == -1)
324 			warn("system `%s'", command);
325 		else
326 			exit(eflag ? getshellstatus(ret) : EXIT_FAILURE);
327 	}
328 
329 	fail();
330 }
331 
332 static void
333 fail(void)
334 {
335 
336 	(void)kill(0, SIGTERM);
337 	done(EXIT_FAILURE);
338 }
339 
340 static void
341 done(int status)
342 {
343 	time_t tvec;
344 
345 	if (subchild) {
346 		tvec = time(NULL);
347 		if (rawout)
348 			record(fscript, NULL, 0, 'e');
349 		else if (!quiet)
350 			(void)fprintf(fscript,"\nScript done on %s",
351 			    ctime(&tvec));
352 		(void)fclose(fscript);
353 		(void)close(master);
354 	} else {
355 		if (isterm)
356 			(void)tcsetattr(STDIN_FILENO, TCSAFLUSH, &tt);
357 		if (!quiet)
358 			(void)printf("Script done, output file is %s\n", fname);
359 	}
360 	exit(status);
361 }
362 
363 static void
364 record(FILE *fp, char *buf, size_t cc, int direction)
365 {
366 	struct iovec iov[2];
367 	struct stamp stamp;
368 	struct timeval tv;
369 
370 	(void)gettimeofday(&tv, NULL);
371 	stamp.scr_len = cc;
372 	stamp.scr_sec = tv.tv_sec;
373 	stamp.scr_usec = tv.tv_usec;
374 	stamp.scr_direction = direction;
375 	iov[0].iov_len = sizeof(stamp);
376 	iov[0].iov_base = &stamp;
377 	iov[1].iov_len = cc;
378 	iov[1].iov_base = buf;
379 	if (writev(fileno(fp), &iov[0], 2) == -1)
380 		err(EXIT_FAILURE, "writev");
381 }
382 
383 static void
384 consume(FILE *fp, off_t len, char *buf, int reg)
385 {
386 	size_t l;
387 
388 	if (reg) {
389 		if (fseeko(fp, len, SEEK_CUR) == -1)
390 			err(EXIT_FAILURE, NULL);
391 	}
392 	else {
393 		while (len > 0) {
394 			l = MIN(DEF_BUF, len);
395 			if (fread(buf, sizeof(char), l, fp) != l)
396 				err(EXIT_FAILURE, "cannot read buffer");
397 			len -= l;
398 		}
399 	}
400 }
401 
402 #define swapstamp(stamp) do { \
403 	if (stamp.scr_direction > 0xff) { \
404 		stamp.scr_len = bswap64(stamp.scr_len); \
405 		stamp.scr_sec = bswap64(stamp.scr_sec); \
406 		stamp.scr_usec = bswap32(stamp.scr_usec); \
407 		stamp.scr_direction = bswap32(stamp.scr_direction); \
408 	} \
409 } while (0/*CONSTCOND*/)
410 
411 static void
412 termset(void)
413 {
414 	struct termios traw;
415 
416 	if (tcgetattr(STDOUT_FILENO, &tt) == -1) {
417 		if (errno != ENOTTY) /* For debugger. */
418 			err(EXIT_FAILURE, "tcgetattr");
419 		return;
420 	}
421 	isterm = 1;
422 	traw = tt;
423 	cfmakeraw(&traw);
424 	traw.c_lflag |= ISIG;
425         (void)tcsetattr(STDOUT_FILENO, TCSANOW, &traw);
426 }
427 
428 static void
429 termreset(void)
430 {
431 	if (isterm)
432 		(void)tcsetattr(STDOUT_FILENO, TCSADRAIN, &tt);
433 
434 	isterm = 0;
435 }
436 
437 static void
438 playback(FILE *fp)
439 {
440 	struct timespec tsi, tso;
441 	struct stamp stamp;
442 	struct stat pst;
443 	char buf[DEF_BUF];
444 	off_t nread, save_len;
445 	size_t l;
446 	time_t tclock;
447 	int reg;
448 
449 	if (fstat(fileno(fp), &pst) == -1)
450 		err(EXIT_FAILURE, "fstat failed");
451 
452 	reg = S_ISREG(pst.st_mode);
453 
454 	for (nread = 0; !reg || nread < pst.st_size; nread += save_len) {
455 		if (fread(&stamp, sizeof(stamp), 1, fp) != 1) {
456 			if (reg)
457 				err(EXIT_FAILURE, "reading playback header");
458 			else
459 				break;
460 		}
461 		swapstamp(stamp);
462 		save_len = sizeof(stamp);
463 
464 		if (reg && stamp.scr_len >
465 		    (uint64_t)(pst.st_size - save_len) - nread)
466 			errx(EXIT_FAILURE, "invalid stamp");
467 
468 		save_len += stamp.scr_len;
469 		tclock = stamp.scr_sec;
470 		tso.tv_sec = stamp.scr_sec;
471 		tso.tv_nsec = stamp.scr_usec * 1000;
472 
473 		switch (stamp.scr_direction) {
474 		case 's':
475 			if (!quiet)
476 			    (void)printf("Script started on %s",
477 				ctime(&tclock));
478 			tsi = tso;
479 			(void)consume(fp, stamp.scr_len, buf, reg);
480 			termset();
481 			atexit(termreset);
482 			break;
483 		case 'e':
484 			termreset();
485 			if (!quiet)
486 				(void)printf("\nScript done on %s",
487 				    ctime(&tclock));
488 			(void)consume(fp, stamp.scr_len, buf, reg);
489 			break;
490 		case 'i':
491 			/* throw input away */
492 			(void)consume(fp, stamp.scr_len, buf, reg);
493 			break;
494 		case 'o':
495 			tsi.tv_sec = tso.tv_sec - tsi.tv_sec;
496 			tsi.tv_nsec = tso.tv_nsec - tsi.tv_nsec;
497 			if (tsi.tv_nsec < 0) {
498 				tsi.tv_sec -= 1;
499 				tsi.tv_nsec += 1000000000;
500 			}
501 			if (usesleep)
502 				(void)nanosleep(&tsi, NULL);
503 			tsi = tso;
504 			while (stamp.scr_len > 0) {
505 				l = MIN(DEF_BUF, stamp.scr_len);
506 				if (fread(buf, sizeof(char), l, fp) != l)
507 					err(EXIT_FAILURE, "cannot read buffer");
508 
509 				(void)write(STDOUT_FILENO, buf, l);
510 				stamp.scr_len -= l;
511 			}
512 			break;
513 		default:
514 			errx(EXIT_FAILURE, "invalid direction %u",
515 			    stamp.scr_direction);
516 		}
517 	}
518 	(void)fclose(fp);
519 	exit(EXIT_SUCCESS);
520 }
521