xref: /netbsd-src/usr.bin/script/script.c (revision 836e5e938d6134d40d4e31cde52a887ff3256430)
1 /*	$NetBSD: script.c,v 1.34 2023/05/09 15:43:39 hgutch 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 1.34 2023/05/09 15:43:39 hgutch 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
main(int argc,char * argv[])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 		(void)xsignal(SIGCHLD, SIG_DFL);
196 		subchild = child = fork();
197 		if (child == -1) {
198 			warn("fork");
199 			fail();
200 		}
201 		if (child)
202 			dooutput();
203 		else
204 			doshell(command);
205 	}
206 
207 	if (!rawout)
208 		(void)fclose(fscript);
209 	while (!die && (scc = read(STDIN_FILENO, ibuf, BUFSIZ)) > 0) {
210 		cc = (size_t)scc;
211 		if (rawout)
212 			record(fscript, ibuf, cc, 'i');
213 		(void)write(master, ibuf, cc);
214 	}
215 	done(cstat);
216 }
217 
218 /**
219  * wrapper around sigaction() because we want POSIX semantics:
220  * no auto-restarting of interrupted slow syscalls.
221  */
222 static sig_t
xsignal(int signo,sig_t handler)223 xsignal(int signo, sig_t handler)
224 {
225 	struct sigaction sa, osa;
226 
227 	sa.sa_handler = handler;
228 	sa.sa_flags = 0;
229 	sigemptyset(&sa.sa_mask);
230 	if (sigaction(signo, &sa, &osa) == -1)
231 		return SIG_ERR;
232 	return osa.sa_handler;
233 }
234 
235 static int
getshellstatus(int status)236 getshellstatus(int status)
237 {
238 	if (WIFEXITED(status))
239 		return WEXITSTATUS(status);
240 	if (WIFSIGNALED(status))
241 		return 128 + WTERMSIG(status);
242 	return EXIT_FAILURE;
243 }
244 
245 static void
finish(int signo)246 finish(int signo)
247 {
248 	int pid, status;
249 
250 	die = 0;
251 	while ((pid = wait(&status)) > 0)
252 		if (pid == child) {
253 			die = 1;
254 		}
255 
256 	if (!die)
257 		return;
258 	done(eflag ? getshellstatus(status) : EXIT_SUCCESS);
259 }
260 
261 static void
dooutput(void)262 dooutput(void)
263 {
264 	struct itimerval value;
265 	ssize_t scc;
266 	size_t cc;
267 	time_t tvec;
268 	char obuf[BUFSIZ];
269 
270 	(void)close(STDIN_FILENO);
271 	tvec = time(NULL);
272 	if (rawout)
273 		record(fscript, NULL, 0, 's');
274 	else if (!quiet)
275 		(void)fprintf(fscript, "Script started on %s", ctime(&tvec));
276 
277 	(void)signal(SIGALRM, scriptflush);
278 	value.it_interval.tv_sec = SECSPERMIN / 2;
279 	value.it_interval.tv_usec = 0;
280 	value.it_value = value.it_interval;
281 	(void)setitimer(ITIMER_REAL, &value, NULL);
282 	for (;;) {
283 		scc = read(master, obuf, sizeof(obuf));
284 		if (scc <= 0)
285 			break;
286 		cc = (size_t)scc;
287 		(void)write(STDOUT_FILENO, obuf, cc);
288 		if (rawout)
289 			record(fscript, obuf, cc, 'o');
290 		else
291 			(void)fwrite(obuf, 1, cc, fscript);
292 		outcc += cc;
293 		if (flush)
294 			(void)fflush(fscript);
295 	}
296 	done(cstat);
297 }
298 
299 static void
scriptflush(int signo)300 scriptflush(int signo)
301 {
302 	if (outcc) {
303 		(void)fflush(fscript);
304 		outcc = 0;
305 	}
306 }
307 
308 static void
doshell(const char * command)309 doshell(const char *command)
310 {
311 	const char *shell;
312 
313 	(void)close(master);
314 	(void)fclose(fscript);
315 	login_tty(slave);
316 	if (command == NULL) {
317 		shell = getenv("SHELL");
318 		if (shell == NULL)
319 			shell = _PATH_BSHELL;
320 		execl(shell, shell, "-i", NULL);
321 		warn("execl `%s'", shell);
322 	} else {
323 		int ret = system(command);
324 		if (ret == -1)
325 			warn("system `%s'", command);
326 		else
327 			exit(eflag ? getshellstatus(ret) : EXIT_FAILURE);
328 	}
329 
330 	fail();
331 }
332 
333 static void
fail(void)334 fail(void)
335 {
336 
337 	(void)kill(0, SIGTERM);
338 	done(EXIT_FAILURE);
339 }
340 
341 static void
done(int status)342 done(int status)
343 {
344 	time_t tvec;
345 
346 	if (subchild) {
347 		tvec = time(NULL);
348 		if (rawout)
349 			record(fscript, NULL, 0, 'e');
350 		else if (!quiet)
351 			(void)fprintf(fscript,"\nScript done on %s",
352 			    ctime(&tvec));
353 		(void)fclose(fscript);
354 		(void)close(master);
355 	} else {
356 		if (isterm)
357 			(void)tcsetattr(STDIN_FILENO, TCSAFLUSH, &tt);
358 		if (!quiet)
359 			(void)printf("Script done, output file is %s\n", fname);
360 	}
361 	exit(status);
362 }
363 
364 static void
record(FILE * fp,char * buf,size_t cc,int direction)365 record(FILE *fp, char *buf, size_t cc, int direction)
366 {
367 	struct iovec iov[2];
368 	struct stamp stamp;
369 	struct timeval tv;
370 
371 	(void)gettimeofday(&tv, NULL);
372 	stamp.scr_len = cc;
373 	stamp.scr_sec = tv.tv_sec;
374 	stamp.scr_usec = tv.tv_usec;
375 	stamp.scr_direction = direction;
376 	iov[0].iov_len = sizeof(stamp);
377 	iov[0].iov_base = &stamp;
378 	iov[1].iov_len = cc;
379 	iov[1].iov_base = buf;
380 	if (writev(fileno(fp), &iov[0], 2) == -1)
381 		err(EXIT_FAILURE, "writev");
382 }
383 
384 static void
consume(FILE * fp,off_t len,char * buf,int reg)385 consume(FILE *fp, off_t len, char *buf, int reg)
386 {
387 	size_t l;
388 
389 	if (reg) {
390 		if (fseeko(fp, len, SEEK_CUR) == -1)
391 			err(EXIT_FAILURE, NULL);
392 	}
393 	else {
394 		while (len > 0) {
395 			l = MIN(DEF_BUF, len);
396 			if (fread(buf, sizeof(char), l, fp) != l)
397 				err(EXIT_FAILURE, "cannot read buffer");
398 			len -= l;
399 		}
400 	}
401 }
402 
403 #define swapstamp(stamp) do { \
404 	if (stamp.scr_direction > 0xff) { \
405 		stamp.scr_len = bswap64(stamp.scr_len); \
406 		stamp.scr_sec = bswap64(stamp.scr_sec); \
407 		stamp.scr_usec = bswap32(stamp.scr_usec); \
408 		stamp.scr_direction = bswap32(stamp.scr_direction); \
409 	} \
410 } while (0/*CONSTCOND*/)
411 
412 static void
termset(void)413 termset(void)
414 {
415 	struct termios traw;
416 
417 	if (tcgetattr(STDOUT_FILENO, &tt) == -1) {
418 		if (errno != ENOTTY) /* For debugger. */
419 			err(EXIT_FAILURE, "tcgetattr");
420 		return;
421 	}
422 	isterm = 1;
423 	traw = tt;
424 	cfmakeraw(&traw);
425 	traw.c_lflag |= ISIG;
426         (void)tcsetattr(STDOUT_FILENO, TCSANOW, &traw);
427 }
428 
429 static void
termreset(void)430 termreset(void)
431 {
432 	if (isterm)
433 		(void)tcsetattr(STDOUT_FILENO, TCSADRAIN, &tt);
434 
435 	isterm = 0;
436 }
437 
438 static void
playback(FILE * fp)439 playback(FILE *fp)
440 {
441 	struct timespec tsi, tso;
442 	struct stamp stamp;
443 	struct stat pst;
444 	char buf[DEF_BUF];
445 	off_t nread, save_len;
446 	size_t l;
447 	time_t tclock;
448 	int reg;
449 
450 	if (fstat(fileno(fp), &pst) == -1)
451 		err(EXIT_FAILURE, "fstat failed");
452 
453 	reg = S_ISREG(pst.st_mode);
454 
455 	for (nread = 0; !reg || nread < pst.st_size; nread += save_len) {
456 		if (fread(&stamp, sizeof(stamp), 1, fp) != 1) {
457 			if (reg)
458 				err(EXIT_FAILURE, "reading playback header");
459 			else
460 				break;
461 		}
462 		swapstamp(stamp);
463 		save_len = sizeof(stamp);
464 
465 		if (reg && stamp.scr_len >
466 		    (uint64_t)(pst.st_size - save_len) - nread)
467 			errx(EXIT_FAILURE, "invalid stamp");
468 
469 		save_len += stamp.scr_len;
470 		tclock = stamp.scr_sec;
471 		tso.tv_sec = stamp.scr_sec;
472 		tso.tv_nsec = stamp.scr_usec * 1000;
473 
474 		switch (stamp.scr_direction) {
475 		case 's':
476 			if (!quiet)
477 			    (void)printf("Script started on %s",
478 				ctime(&tclock));
479 			tsi = tso;
480 			(void)consume(fp, stamp.scr_len, buf, reg);
481 			termset();
482 			atexit(termreset);
483 			break;
484 		case 'e':
485 			termreset();
486 			if (!quiet)
487 				(void)printf("\nScript done on %s",
488 				    ctime(&tclock));
489 			(void)consume(fp, stamp.scr_len, buf, reg);
490 			break;
491 		case 'i':
492 			/* throw input away */
493 			(void)consume(fp, stamp.scr_len, buf, reg);
494 			break;
495 		case 'o':
496 			tsi.tv_sec = tso.tv_sec - tsi.tv_sec;
497 			tsi.tv_nsec = tso.tv_nsec - tsi.tv_nsec;
498 			if (tsi.tv_nsec < 0) {
499 				tsi.tv_sec -= 1;
500 				tsi.tv_nsec += 1000000000;
501 			}
502 			if (usesleep)
503 				(void)nanosleep(&tsi, NULL);
504 			tsi = tso;
505 			while (stamp.scr_len > 0) {
506 				l = MIN(DEF_BUF, stamp.scr_len);
507 				if (fread(buf, sizeof(char), l, fp) != l)
508 					err(EXIT_FAILURE, "cannot read buffer");
509 
510 				(void)write(STDOUT_FILENO, buf, l);
511 				stamp.scr_len -= l;
512 			}
513 			break;
514 		default:
515 			errx(EXIT_FAILURE, "invalid direction %u",
516 			    stamp.scr_direction);
517 		}
518 	}
519 	(void)fclose(fp);
520 	exit(EXIT_SUCCESS);
521 }
522