/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved */


/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

/*      Portions Copyright(c) 1988, Sun Microsystems, Inc.      */
/*      All Rights Reserved.                                    */

/*
 * script: Produce a record of a terminal session.
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <locale.h>
#include <time.h>
#include <sys/stropts.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/termios.h>
#include <sys/file.h>
#include <errno.h>

int     grantpt();
int     unlockpt();
char    *ptsname();
void    doinput() __NORETURN;
void    dooutput();
void    doshell();
void    fixtty();
void    fail();
void    done() __NORETURN;
void    getmanager();
void    getsubsid();

char    *shell;
FILE    *fscript;
int     manager;        /* file descriptor for manager pseudo-tty */
int     subsid;         /* file descriptor for subsidiary pseudo-tty */
int     child;
int     subchild;
char    *fname = "typescript";
void    sigwinch();
void    finish();

struct  termios b;
struct  winsize size;
int     lb;
int     l;
char    *mptname = "/dev/ptmx"; /* manager pseudo-tty device */

int     aflg;

int
main(int argc, char *argv[])
{
        uid_t ruidt;
        gid_t gidt;

        (void) setlocale(LC_ALL, "");
#if !defined(TEXT_DOMAIN)
#define TEXT_DOMAIN     "SYS_TEST"
#endif
        (void) textdomain(TEXT_DOMAIN);

        shell = getenv("SHELL");
        if (shell == NULL)
                shell = "/bin/sh";
        argc--, argv++;
        while (argc > 0 && argv[0][0] == '-') {
                switch (argv[0][1]) {

                case 'a':
                        aflg++;
                        break;

                default:
                        fprintf(stderr,
                            gettext("usage: script [ -a ] [ typescript ]\n"));
                        exit(1);
                }
                argc--, argv++;
        }
        if (argc > 0)
                fname = argv[0];
        ruidt = getuid();
        gidt = getgid();
        if ((fscript = fopen(fname, aflg ? "a" : "w")) == NULL) {
                perror(fname);
                fail();
        }
        setbuf(fscript, NULL);
        chown(fname, ruidt, gidt);
        getmanager();
        printf(gettext("Script started, file is %s\n"), fname);
        fixtty();

        (void) signal(SIGCHLD, finish);
        child = fork();
        if (child < 0) {
                perror("fork");
                fail();
        }
        if (child == 0) {
                subchild = child = fork();
                if (child < 0) {
                        perror("fork");
                        fail();
                }
                if (child)
                        dooutput();
                else
                        doshell();
        }
        doinput();
        /* NOTREACHED */
        return (0);
}

void
doinput()
{
        char ibuf[BUFSIZ];
        int cc;

        (void) fclose(fscript);
        sigset(SIGWINCH, sigwinch);

        while ((cc = read(0, ibuf, BUFSIZ)) != 0) {
                if (cc == -1) {
                        if (errno == EINTR) {   /* SIGWINCH probably */
                                continue;
                        } else {
                                break;
                        }
                }
                (void) write(manager, ibuf, cc);
        }
        done();
}

void
sigwinch()
{
        struct winsize ws;

        if (ioctl(0, TIOCGWINSZ, &ws) == 0)
                (void) ioctl(manager, TIOCSWINSZ, &ws);
}

#include <sys/wait.h>

void
finish()
{
        int status;
        register int pid;
        register int die = 0;

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

        if (die)
                done();
}

void
dooutput()
{
        time_t tvec;
        char obuf[BUFSIZ];
        char tbuf[BUFSIZ];
        int cc;

        (void) close(0);
        tvec = time((time_t *)0);
        strftime(tbuf, BUFSIZ, "%c", localtime(&tvec));
        fprintf(fscript, gettext("Script started on %s\n"), tbuf);
        for (;;) {
                cc = read(manager, obuf, sizeof (obuf));
                if (cc <= 0)
                        break;
                (void) write(1, obuf, cc);
                (void) fwrite(obuf, 1, cc, fscript);
        }
        done();
}

void
doshell()
{

        setpgrp();      /* relinquish control terminal */
        getsubsid();
        (void) close(manager);
        (void) fclose(fscript);
        (void) dup2(subsid, 0);
        (void) dup2(subsid, 1);
        (void) dup2(subsid, 2);
        (void) close(subsid);
        execl(shell, shell, "-i", (char *)0);
        perror(shell);
        fail();
}

void
fixtty()
{
        struct termios sbuf;

        sbuf = b;
        sbuf.c_iflag &= ~(INLCR|IGNCR|ICRNL|IUCLC|IXON);
        sbuf.c_oflag &= ~OPOST;
        sbuf.c_lflag &= ~(ICANON|ISIG|ECHO);
        sbuf.c_cc[VMIN] = 1;
        sbuf.c_cc[VTIME] = 0;
        (void) ioctl(0, TCSETSF, (char *)&sbuf);
}

void
fail()
{

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

void
done()
{
        time_t tvec;
        char tbuf[BUFSIZ];

        if (subchild) {
                tvec = time((time_t *)0);
                strftime(tbuf, BUFSIZ, "%c", localtime(&tvec));
                fprintf(fscript, gettext("\nscript done on %s\n"), tbuf);
                (void) fclose(fscript);
                (void) close(manager);
        } else {
                (void) ioctl(0, TCSETSW, (char *)&b);
                printf(gettext("Script done, file is %s\n"), fname);
        }
        exit(0);
}

void
getmanager()
{
        struct stat stb;

        if ((manager = open(mptname, O_RDWR)) >= 0) { /* a pseudo-tty is free */
                (void) ioctl(0, TCGETS, (char *)&b);
                (void) ioctl(0, TIOCGWINSZ, (char *)&size);
                return;
        } else {                                /* out of pseudo-tty's */
                perror(mptname);
                fprintf(stderr, gettext("Out of pseudo-tty's\n"));
                fail();
        }
}

void
getsubsid()
{
        char *subsidname;       /* name of subsidiary pseudo-tty */

        grantpt(manager);               /* change permissions of subsidiary */
        unlockpt(manager);                      /* unlock subsidiary */
        subsidname = ptsname(manager);          /* get name of subsidiary */
        subsid = open(subsidname, O_RDWR);      /* open subsidiary */
        if (subsid < 0) {                       /* error opening subsidiary */
                perror(subsidname);
                fail();
        }
        ioctl(subsid, I_PUSH, "ptem");  /* push pt hw emulation module */
        ioctl(subsid, I_PUSH, "ldterm");        /* push line discipline */

        (void) ioctl(subsid, TCSETSF, (char *)&b);
        (void) ioctl(subsid, TIOCSWINSZ, (char *)&size);
}