xref: /netbsd-src/usr.bin/script/script.c (revision 503a97f998b37fbde1e80d856ff2b009b5d71dff)
1 /*	$NetBSD: script.c,v 1.25 2020/08/07 13:36:28 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 1.25 2020/08/07 13:36:28 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 int	isterm;
85 static struct	termios tt;
86 
87 __dead static void	done(void);
88 __dead static void	dooutput(void);
89 __dead static void	doshell(const char *);
90 __dead static void	fail(void);
91 static void	finish(int);
92 static void	scriptflush(int);
93 static void	record(FILE *, char *, size_t, int);
94 static void	consume(FILE *, off_t, char *, int);
95 __dead static void	playback(FILE *);
96 
97 int
98 main(int argc, char *argv[])
99 {
100 	ssize_t scc;
101 	size_t cc;
102 	struct termios rtt;
103 	struct winsize win;
104 	int aflg, pflg, ch;
105 	char ibuf[BUFSIZ];
106 	const char *command;
107 
108 	aflg = 0;
109 	pflg = 0;
110 	usesleep = 1;
111 	rawout = 0;
112 	quiet = 0;
113 	flush = 0;
114 	command = NULL;
115 	while ((ch = getopt(argc, argv, "ac:dfpqr")) != -1)
116 		switch(ch) {
117 		case 'a':
118 			aflg = 1;
119 			break;
120 		case 'c':
121 			command = optarg;
122 			break;
123 		case 'd':
124 			usesleep = 0;
125 			break;
126 		case 'f':
127 			flush = 1;
128 			break;
129 		case 'p':
130 			pflg = 1;
131 			break;
132 		case 'q':
133 			quiet = 1;
134 			break;
135 		case 'r':
136 			rawout = 1;
137 			break;
138 		case '?':
139 		default:
140 			(void)fprintf(stderr,
141 			    "Usage: %s [-c <command>][-adfpqr] [file]\n",
142 			    getprogname());
143 			exit(EXIT_FAILURE);
144 		}
145 	argc -= optind;
146 	argv += optind;
147 
148 	if (argc > 0)
149 		fname = argv[0];
150 	else
151 		fname = "typescript";
152 
153 	if ((fscript = fopen(fname, pflg ? "r" : aflg ? "a" : "w")) == NULL)
154 		err(EXIT_FAILURE, "fopen %s", fname);
155 
156 	if (pflg)
157 		playback(fscript);
158 
159 	if (tcgetattr(STDIN_FILENO, &tt) == -1 ||
160 	    ioctl(STDIN_FILENO, TIOCGWINSZ, &win) == -1) {
161 		switch (errno) {
162 		case ENOTTY:
163 			if (openpty(&master, &slave, NULL, NULL, NULL) == -1)
164 				err(EXIT_FAILURE, "openpty");
165 			break;
166 		case EBADF:
167 			err(EXIT_FAILURE, "%d not valid fd", STDIN_FILENO);
168 		default: /* errno == EFAULT or EINVAL for ioctl. Not reached in practice. */
169 			err(EXIT_FAILURE, "ioctl");
170 		}
171 	} else {
172 		if (openpty(&master, &slave, NULL, &tt, &win) == -1)
173 			err(EXIT_FAILURE, "openpty");
174 		isterm = 1;
175 	}
176 
177 	if (!quiet)
178 		(void)printf("Script started, output file is %s\n", fname);
179 
180 	if (isterm) {
181 		rtt = tt;
182 		cfmakeraw(&rtt);
183 		rtt.c_lflag &= ~ECHO;
184 		(void)tcsetattr(STDIN_FILENO, TCSAFLUSH, &rtt);
185 	}
186 
187 	(void)signal(SIGCHLD, finish);
188 	child = fork();
189 	if (child == -1) {
190 		warn("fork");
191 		fail();
192 	}
193 	if (child == 0) {
194 		subchild = child = fork();
195 		if (child == -1) {
196 			warn("fork");
197 			fail();
198 		}
199 		if (child)
200 			dooutput();
201 		else
202 			doshell(command);
203 	}
204 
205 	if (!rawout)
206 		(void)fclose(fscript);
207 	while ((scc = read(STDIN_FILENO, ibuf, BUFSIZ)) > 0) {
208 		cc = (size_t)scc;
209 		if (rawout)
210 			record(fscript, ibuf, cc, 'i');
211 		(void)write(master, ibuf, cc);
212 	}
213 	done();
214 	/* NOTREACHED */
215 	return EXIT_SUCCESS;
216 }
217 
218 static void
219 finish(int signo)
220 {
221 	int die, pid, status;
222 
223 	die = 0;
224 	while ((pid = wait3(&status, WNOHANG, 0)) > 0)
225 		if (pid == child)
226 			die = 1;
227 
228 	if (die)
229 		done();
230 }
231 
232 static void
233 dooutput(void)
234 {
235 	struct itimerval value;
236 	ssize_t scc;
237 	size_t cc;
238 	time_t tvec;
239 	char obuf[BUFSIZ];
240 
241 	(void)close(STDIN_FILENO);
242 	tvec = time(NULL);
243 	if (rawout)
244 		record(fscript, NULL, 0, 's');
245 	else if (!quiet)
246 		(void)fprintf(fscript, "Script started on %s", ctime(&tvec));
247 
248 	(void)signal(SIGALRM, scriptflush);
249 	value.it_interval.tv_sec = SECSPERMIN / 2;
250 	value.it_interval.tv_usec = 0;
251 	value.it_value = value.it_interval;
252 	(void)setitimer(ITIMER_REAL, &value, NULL);
253 	for (;;) {
254 		scc = read(master, obuf, sizeof(obuf));
255 		if (scc <= 0)
256 			break;
257 		cc = (size_t)scc;
258 		(void)write(1, obuf, cc);
259 		if (rawout)
260 			record(fscript, obuf, cc, 'o');
261 		else
262 			(void)fwrite(obuf, 1, cc, fscript);
263 		outcc += cc;
264 		if (flush)
265 			(void)fflush(fscript);
266 	}
267 	done();
268 }
269 
270 static void
271 scriptflush(int signo)
272 {
273 	if (outcc) {
274 		(void)fflush(fscript);
275 		outcc = 0;
276 	}
277 }
278 
279 static void
280 doshell(const char *command)
281 {
282 	const char *shell;
283 
284 	(void)close(master);
285 	(void)fclose(fscript);
286 	login_tty(slave);
287 	if (command == NULL) {
288 		shell = getenv("SHELL");
289 		if (shell == NULL)
290 			shell = _PATH_BSHELL;
291 		execl(shell, shell, "-i", NULL);
292 		warn("execl `%s'", shell);
293 	} else {
294 		if (system(command) == -1)
295 			warn("system `%s'", command);
296 	}
297 
298 	fail();
299 }
300 
301 static void
302 fail(void)
303 {
304 
305 	(void)kill(0, SIGTERM);
306 	done();
307 }
308 
309 static void
310 done(void)
311 {
312 	time_t tvec;
313 
314 	if (subchild) {
315 		tvec = time(NULL);
316 		if (rawout)
317 			record(fscript, NULL, 0, 'e');
318 		else if (!quiet)
319 			(void)fprintf(fscript,"\nScript done on %s",
320 			    ctime(&tvec));
321 		(void)fclose(fscript);
322 		(void)close(master);
323 	} else {
324 		if (isterm)
325 			(void)tcsetattr(STDIN_FILENO, TCSAFLUSH, &tt);
326 		if (!quiet)
327 			(void)printf("Script done, output file is %s\n", fname);
328 	}
329 	exit(EXIT_SUCCESS);
330 }
331 
332 static void
333 record(FILE *fp, char *buf, size_t cc, int direction)
334 {
335 	struct iovec iov[2];
336 	struct stamp stamp;
337 	struct timeval tv;
338 
339 	(void)gettimeofday(&tv, NULL);
340 	stamp.scr_len = cc;
341 	stamp.scr_sec = tv.tv_sec;
342 	stamp.scr_usec = tv.tv_usec;
343 	stamp.scr_direction = direction;
344 	iov[0].iov_len = sizeof(stamp);
345 	iov[0].iov_base = &stamp;
346 	iov[1].iov_len = cc;
347 	iov[1].iov_base = buf;
348 	if (writev(fileno(fp), &iov[0], 2) == -1)
349 		err(EXIT_FAILURE, "writev");
350 }
351 
352 static void
353 consume(FILE *fp, off_t len, char *buf, int reg)
354 {
355 	size_t l;
356 
357 	if (reg) {
358 		if (fseeko(fp, len, SEEK_CUR) == -1)
359 			err(EXIT_FAILURE, NULL);
360 	}
361 	else {
362 		while (len > 0) {
363 			l = MIN(DEF_BUF, len);
364 			if (fread(buf, sizeof(char), l, fp) != l)
365 				err(EXIT_FAILURE, "cannot read buffer");
366 			len -= l;
367 		}
368 	}
369 }
370 
371 #define swapstamp(stamp) do { \
372 	if (stamp.scr_direction > 0xff) { \
373 		stamp.scr_len = bswap64(stamp.scr_len); \
374 		stamp.scr_sec = bswap64(stamp.scr_sec); \
375 		stamp.scr_usec = bswap32(stamp.scr_usec); \
376 		stamp.scr_direction = bswap32(stamp.scr_direction); \
377 	} \
378 } while (0/*CONSTCOND*/)
379 
380 static void
381 termset(void)
382 {
383 	struct termios traw;
384 
385 	if (tcgetattr(STDOUT_FILENO, &tt) == -1) {
386 		if (errno == EBADF)
387 			err(EXIT_FAILURE, "%d not valid fd", STDOUT_FILENO);
388 		/* errno == ENOTTY */
389 		return;
390 	}
391 	isterm = 1;
392 	traw = tt;
393 	cfmakeraw(&traw);
394 	traw.c_lflag |= ISIG;
395         (void)tcsetattr(STDOUT_FILENO, TCSANOW, &traw);
396 }
397 
398 static void
399 termreset(void)
400 {
401 	if (isterm)
402 		(void)tcsetattr(STDOUT_FILENO, TCSADRAIN, &tt);
403 
404 	isterm = 0;
405 }
406 
407 static void
408 playback(FILE *fp)
409 {
410 	struct timespec tsi, tso;
411 	struct stamp stamp;
412 	struct stat pst;
413 	char buf[DEF_BUF];
414 	off_t nread, save_len;
415 	size_t l;
416 	time_t tclock;
417 	int reg;
418 
419 	if (fstat(fileno(fp), &pst) == -1)
420 		err(EXIT_FAILURE, "fstat failed");
421 
422 	reg = S_ISREG(pst.st_mode);
423 
424 	for (nread = 0; !reg || nread < pst.st_size; nread += save_len) {
425 		if (fread(&stamp, sizeof(stamp), 1, fp) != 1) {
426 			if (reg)
427 				err(EXIT_FAILURE, "reading playback header");
428 			else
429 				break;
430 		}
431 		swapstamp(stamp);
432 		save_len = sizeof(stamp);
433 
434 		if (reg && stamp.scr_len >
435 		    (uint64_t)(pst.st_size - save_len) - nread)
436 			errx(EXIT_FAILURE, "invalid stamp");
437 
438 		save_len += stamp.scr_len;
439 		tclock = stamp.scr_sec;
440 		tso.tv_sec = stamp.scr_sec;
441 		tso.tv_nsec = stamp.scr_usec * 1000;
442 
443 		switch (stamp.scr_direction) {
444 		case 's':
445 			if (!quiet)
446 			    (void)printf("Script started on %s",
447 				ctime(&tclock));
448 			tsi = tso;
449 			(void)consume(fp, stamp.scr_len, buf, reg);
450 			termset();
451 			atexit(termreset);
452 			break;
453 		case 'e':
454 			termreset();
455 			if (!quiet)
456 				(void)printf("\nScript done on %s",
457 				    ctime(&tclock));
458 			(void)consume(fp, stamp.scr_len, buf, reg);
459 			break;
460 		case 'i':
461 			/* throw input away */
462 			(void)consume(fp, stamp.scr_len, buf, reg);
463 			break;
464 		case 'o':
465 			tsi.tv_sec = tso.tv_sec - tsi.tv_sec;
466 			tsi.tv_nsec = tso.tv_nsec - tsi.tv_nsec;
467 			if (tsi.tv_nsec < 0) {
468 				tsi.tv_sec -= 1;
469 				tsi.tv_nsec += 1000000000;
470 			}
471 			if (usesleep)
472 				(void)nanosleep(&tsi, NULL);
473 			tsi = tso;
474 			while (stamp.scr_len > 0) {
475 				l = MIN(DEF_BUF, stamp.scr_len);
476 				if (fread(buf, sizeof(char), l, fp) != l)
477 					err(EXIT_FAILURE, "cannot read buffer");
478 
479 				(void)write(STDOUT_FILENO, buf, l);
480 				stamp.scr_len -= l;
481 			}
482 			break;
483 		default:
484 			errx(EXIT_FAILURE, "invalid direction %u",
485 			    stamp.scr_direction);
486 		}
487 	}
488 	(void)fclose(fp);
489 	exit(EXIT_SUCCESS);
490 }
491