* Copyright (c) 1980, 1992, 1993

/* $NetBSD: script.c,v 1.34 2023/05/09 15:43:39 hgutch Exp $ */

/*
* Copyright (c) 1980, 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1980, 1992, 1993\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)script.c 8.1 (Berkeley) 6/6/93";
#endif
__RCSID("$NetBSD: script.c,v 1.34 2023/05/09 15:43:39 hgutch Exp $");
#endif /* not lint */

#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/param.h>
#include <sys/uio.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <time.h>
#include <tzfile.h>
#include <unistd.h>
#include <util.h>

#define DEF_BUF 65536

struct stamp {
uint64_t scr_len; /* amount of data */
uint64_t scr_sec; /* time it arrived in seconds... */
uint32_t scr_usec; /* ...and microseconds */
uint32_t scr_direction; /* 'i', 'o', etc (also indicates endianness) */
};

static FILE *fscript;
static int master, slave;
static int child, subchild;
static size_t outcc;
static int usesleep, rawout;
static int quiet, flush;
static const char *fname;

static volatile sig_atomic_t die = 0; /* exit if 1 */
static int cstat = EXIT_SUCCESS; /* cmd. exit status */
static int eflag;
static int isterm;
static struct termios tt;

__dead static void done(int);
__dead static void doshell(const char *);
__dead static void fail(void);
static sig_t xsignal(int, sig_t);
__dead static void dooutput(void);
static void finish(int);
static void scriptflush(int);
static void record(FILE *, char *, size_t, int);
static void consume(FILE *, off_t, char *, int);
__dead static void playback(FILE *);

int
main(int argc, char *argv[])
{
ssize_t scc;
size_t cc;
struct termios rtt;
struct winsize win;
int aflg, pflg, ch;
char ibuf[BUFSIZ];
const char *command;

aflg = 0;
pflg = 0;
usesleep = 1;
rawout = 0;
quiet = 0;
flush = 0;
command = NULL;
while ((ch = getopt(argc, argv, "ac:defpqr")) != -1)
switch(ch) {
case 'a':
aflg = 1;
break;
case 'c':
command = optarg;
break;
case 'd':
usesleep = 0;
break;
case 'e':
eflag = 1;
break;
case 'f':
flush = 1;
break;
case 'p':
pflg = 1;
break;
case 'q':
quiet = 1;
break;
case 'r':
rawout = 1;
break;
case '?':
default:
(void)fprintf(stderr,
"Usage: %s [-c <command>][-adefpqr] [file]\n",
getprogname());
exit(EXIT_FAILURE);
}
argc -= optind;
argv += optind;

if (argc > 0)
fname = argv[0];
else
fname = "typescript";

if ((fscript = fopen(fname, pflg ? "r" : aflg ? "a" : "w")) == NULL)
err(EXIT_FAILURE, "fopen %s", fname);

if (pflg)
playback(fscript);

if (tcgetattr(STDIN_FILENO, &tt) == -1 ||
ioctl(STDIN_FILENO, TIOCGWINSZ, &win) == -1) {
if (errno != ENOTTY) /* For debugger. */
err(EXIT_FAILURE, "tcgetattr/ioctl");
if (openpty(&master, &slave, NULL, NULL, NULL) == -1)
err(EXIT_FAILURE, "openpty");
} else {
if (openpty(&master, &slave, NULL, &tt, &win) == -1)
err(EXIT_FAILURE, "openpty");
isterm = 1;
}

if (!quiet)
(void)printf("Script started, output file is %s\n", fname);

if (isterm) {
rtt = tt;
cfmakeraw(&rtt);
rtt.c_lflag &= ~ECHO;
(void)tcsetattr(STDIN_FILENO, TCSAFLUSH, &rtt);
}

(void)xsignal(SIGCHLD, finish);
child = fork();
if (child == -1) {
warn("fork");
fail();
}
if (child == 0) {
(void)xsignal(SIGCHLD, SIG_DFL);
subchild = child = fork();
if (child == -1) {
warn("fork");
fail();
}
if (child)
dooutput();
else
doshell(command);
}

if (!rawout)
(void)fclose(fscript);
while (!die && (scc = read(STDIN_FILENO, ibuf, BUFSIZ)) > 0) {
cc = (size_t)scc;
if (rawout)
record(fscript, ibuf, cc, 'i');
(void)write(master, ibuf, cc);
}
done(cstat);
}

/**
* wrapper around sigaction() because we want POSIX semantics:
* no auto-restarting of interrupted slow syscalls.
*/
static sig_t
xsignal(int signo, sig_t handler)
{
struct sigaction sa, osa;

sa.sa_handler = handler;
sa.sa_flags = 0;
sigemptyset(&sa.sa_mask);
if (sigaction(signo, &sa, &osa) == -1)
return SIG_ERR;
return osa.sa_handler;
}

static int
getshellstatus(int status)
{
if (WIFEXITED(status))
return WEXITSTATUS(status);
if (WIFSIGNALED(status))
return 128 + WTERMSIG(status);
return EXIT_FAILURE;
}

static void
finish(int signo)
{
int pid, status;

die = 0;
while ((pid = wait(&status)) > 0)
if (pid == child) {
die = 1;
}

if (!die)
return;
done(eflag ? getshellstatus(status) : EXIT_SUCCESS);
}

static void
dooutput(void)
{
struct itimerval value;
ssize_t scc;
size_t cc;
time_t tvec;
char obuf[BUFSIZ];

(void)close(STDIN_FILENO);
tvec = time(NULL);
if (rawout)
record(fscript, NULL, 0, 's');
else if (!quiet)
(void)fprintf(fscript, "Script started on %s", ctime(&tvec));

(void)signal(SIGALRM, scriptflush);
value.it_interval.tv_sec = SECSPERMIN / 2;
value.it_interval.tv_usec = 0;
value.it_value = value.it_interval;
(void)setitimer(ITIMER_REAL, &value, NULL);
for (;;) {
scc = read(master, obuf, sizeof(obuf));
if (scc <= 0)
break;
cc = (size_t)scc;
(void)write(STDOUT_FILENO, obuf, cc);
if (rawout)
record(fscript, obuf, cc, 'o');
else
(void)fwrite(obuf, 1, cc, fscript);
outcc += cc;
if (flush)
(void)fflush(fscript);
}
done(cstat);
}

static void
scriptflush(int signo)
{
if (outcc) {
(void)fflush(fscript);
outcc = 0;
}
}

static void
doshell(const char *command)
{
const char *shell;

(void)close(master);
(void)fclose(fscript);
login_tty(slave);
if (command == NULL) {
shell = getenv("SHELL");
if (shell == NULL)
shell = _PATH_BSHELL;
execl(shell, shell, "-i", NULL);
warn("execl `%s'", shell);
} else {
int ret = system(command);
if (ret == -1)
warn("system `%s'", command);
else
exit(eflag ? getshellstatus(ret) : EXIT_FAILURE);
}

fail();
}

static void
fail(void)
{

(void)kill(0, SIGTERM);
done(EXIT_FAILURE);
}

static void
done(int status)
{
time_t tvec;

if (subchild) {
tvec = time(NULL);
if (rawout)
record(fscript, NULL, 0, 'e');
else if (!quiet)
(void)fprintf(fscript,"\nScript done on %s",
ctime(&tvec));
(void)fclose(fscript);
(void)close(master);
} else {
if (isterm)
(void)tcsetattr(STDIN_FILENO, TCSAFLUSH, &tt);
if (!quiet)
(void)printf("Script done, output file is %s\n", fname);
}
exit(status);
}

static void
record(FILE *fp, char *buf, size_t cc, int direction)
{
struct iovec iov[2];
struct stamp stamp;
struct timeval tv;

(void)gettimeofday(&tv, NULL);
stamp.scr_len = cc;
stamp.scr_sec = tv.tv_sec;
stamp.scr_usec = tv.tv_usec;
stamp.scr_direction = direction;
iov[0].iov_len = sizeof(stamp);
iov[0].iov_base = &stamp;
iov[1].iov_len = cc;
iov[1].iov_base = buf;
if (writev(fileno(fp), &iov[0], 2) == -1)
err(EXIT_FAILURE, "writev");
}

static void
consume(FILE *fp, off_t len, char *buf, int reg)
{
size_t l;

if (reg) {
if (fseeko(fp, len, SEEK_CUR) == -1)
err(EXIT_FAILURE, NULL);
}
else {
while (len > 0) {
l = MIN(DEF_BUF, len);
if (fread(buf, sizeof(char), l, fp) != l)
err(EXIT_FAILURE, "cannot read buffer");
len -= l;
}
}
}

#define swapstamp(stamp) do { \
if (stamp.scr_direction > 0xff) { \
stamp.scr_len = bswap64(stamp.scr_len); \
stamp.scr_sec = bswap64(stamp.scr_sec); \
stamp.scr_usec = bswap32(stamp.scr_usec); \
stamp.scr_direction = bswap32(stamp.scr_direction); \
} \
} while (0/*CONSTCOND*/)

static void
termset(void)
{
struct termios traw;

if (tcgetattr(STDOUT_FILENO, &tt) == -1) {
if (errno != ENOTTY) /* For debugger. */
err(EXIT_FAILURE, "tcgetattr");
return;
}
isterm = 1;
traw = tt;
cfmakeraw(&traw);
traw.c_lflag |= ISIG;
(void)tcsetattr(STDOUT_FILENO, TCSANOW, &traw);
}

static void
termreset(void)
{
if (isterm)
(void)tcsetattr(STDOUT_FILENO, TCSADRAIN, &tt);

isterm = 0;
}

static void
playback(FILE *fp)
{
struct timespec tsi, tso;
struct stamp stamp;
struct stat pst;
char buf[DEF_BUF];
off_t nread, save_len;
size_t l;
time_t tclock;
int reg;

if (fstat(fileno(fp), &pst) == -1)
err(EXIT_FAILURE, "fstat failed");

reg = S_ISREG(pst.st_mode);

for (nread = 0; !reg || nread < pst.st_size; nread += save_len) {
if (fread(&stamp, sizeof(stamp), 1, fp) != 1) {
if (reg)
err(EXIT_FAILURE, "reading playback header");
else
break;
}
swapstamp(stamp);
save_len = sizeof(stamp);

if (reg && stamp.scr_len >
(uint64_t)(pst.st_size - save_len) - nread)
errx(EXIT_FAILURE, "invalid stamp");

save_len += stamp.scr_len;
tclock = stamp.scr_sec;
tso.tv_sec = stamp.scr_sec;
tso.tv_nsec = stamp.scr_usec * 1000;

switch (stamp.scr_direction) {
case 's':
if (!quiet)
(void)printf("Script started on %s",
ctime(&tclock));
tsi = tso;
(void)consume(fp, stamp.scr_len, buf, reg);
termset();
atexit(termreset);
break;
case 'e':
termreset();
if (!quiet)
(void)printf("\nScript done on %s",
ctime(&tclock));
(void)consume(fp, stamp.scr_len, buf, reg);
break;
case 'i':
/* throw input away */
(void)consume(fp, stamp.scr_len, buf, reg);
break;
case 'o':
tsi.tv_sec = tso.tv_sec - tsi.tv_sec;
tsi.tv_nsec = tso.tv_nsec - tsi.tv_nsec;
if (tsi.tv_nsec < 0) {
tsi.tv_sec -= 1;
tsi.tv_nsec += 1000000000;
}
if (usesleep)
(void)nanosleep(&tsi, NULL);
tsi = tso;
while (stamp.scr_len > 0) {
l = MIN(DEF_BUF, stamp.scr_len);
if (fread(buf, sizeof(char), l, fp) != l)
err(EXIT_FAILURE, "cannot read buffer");

(void)write(STDOUT_FILENO, buf, l);
stamp.scr_len -= l;
}
break;
default:
errx(EXIT_FAILURE, "invalid direction %u",
stamp.scr_direction);
}
}
(void)fclose(fp);
exit(EXIT_SUCCESS);
}