usr/src/cmd/script.c

static char *sccsid = "@(#)script.c     4.1 (Berkeley) 10/1/80";
 /*
  * script - makes copy of terminal conversation. usage:
  *
  * script [ -n ] [ -s ] [ -q ] [ -a ] [ -S shell ] [ file ]
  * conversation saved in file. default is DFNAME
  */

#define DFNAME "typescript"

#ifdef HOUXP
#define STDSHELL "/bin/sh"
#define NEWSHELL "/p4/3723mrh/bin/csh"
char *shell = NEWSHELL;
#endif

#ifdef HOUXT
#define STDSHELL "/bin/sh"
#define NEWSHELL "/t1/bruce/ucb/bin/csh"
char *shell = NEWSHELL;
#endif

#ifdef CORY
#define STDSHELL "/bin/sh"
#define NEWSHELL "/bin/csh"
char *shell = NEWSHELL;
#endif

#ifdef CC
#define STDSHELL "/bin/sh"
#define NEWSHELL "/bin/csh"
char *shell = NEWSHELL;
#endif

#ifndef STDSHELL
# define V7ENV
#endif

#ifdef V7ENV
#include <signal.h>
/* used for version 7 with environments - gets your environment shell */
#define STDSHELL "/bin/sh"
#define NEWSHELL "/bin/csh"
char *shell;    /* initialized in the code */
# include <sys/types.h>
# include <sys/stat.h>
# define MODE st_mode
# define STAT stat
char *getenv();

#else

/*
 * The following is the structure of the block returned by
 * the stat and fstat system calls.
 */

struct inode {
        char    i_minor;        /* +0: minor device of i-node */
        char    i_major;        /* +1: major device */
        int     i_number;       /* +2 */
        int     i_flags;        /* +4: see below */
        char    i_nlinks;       /* +6: number of links to file */
        char    i_uid;          /* +7: user ID of owner */
        char    i_gid;          /* +8: group ID of owner */
        char    i_size0;        /* +9: high byte of 24-bit size */
        int     i_size1;        /* +10: low word of 24-bit size */
        int     i_addr[8];      /* +12: block numbers or device number */
        int     i_actime[2];    /* +28: time of last access */
        int     i_modtime[2];   /* +32: time of last modification */
};

#define IALLOC  0100000
#define IFMT    060000
#define         IFDIR   040000
#define         IFCHR   020000
#define         IFBLK   060000
#define MODE i_flags
#define STAT inode
#endif

char    *tty;           /* name of users tty so can turn off writes */
char    *ttyname();     /* std subroutine */
int     mode = 0622;    /* old permission bits for users tty */
int     outpipe[2];     /* pipe from shell to output */
int     fd;             /* file descriptor of typescript file */
int     inpipe[2];      /* pipe from input to shell */
long    tvec;           /* current time */
char    buffer[256];    /* for block I/O's */
int     n;              /* number of chars read */
int     status;         /* dummy for wait sys call */
char    *fname;         /* name of typescript file */
int     forkval, ttn;   /* temps for error checking */
int     qflg;           /* true if -q (quiet) flag */
int     aflg;           /* true if -q (append) flag */
struct STAT sbuf;
int     flsh();

main(argc,argv) int argc; char **argv; {

        if ((tty = ttyname(2)) < 0) {
                printf("Nested script not allowed.\n");
                fail();
        }

#ifdef V7ENV
        shell = getenv("SHELL");
#endif

        while ( argc > 1 && argv[1][0] == '-') {
                switch(argv[1][1]) {
                        case 'n':
                                shell = NEWSHELL;
                                break;
                        case 's':
                                shell = STDSHELL;
                                break;
                        case 'S':
                                shell = argv[2];
                                argc--; argv++;
                                break;
                        case 'q':
                                qflg++;
                                break;
                        case 'a':
                                aflg++;
                                break;
                        default:
                                printf("Bad flag %s - ignored\n",argv[1]);
                }
                argc--; argv++;
        }

        if (argc > 1) {
                fname = argv[1];
                if (!aflg && stat(fname,&sbuf) >= 0) {
                        printf("File %s already exists.\n",fname);
                        done();
                }
        } else  fname = DFNAME;
        if (!aflg) {
                fd = creat(fname,0);    /* so can't cat/lpr typescript from inside */
        } else {
                /* try to append to existing file first */
                fd = open(fname,1);
                if (fd >= 0) lseek(fd,0l,2);
                    else     fd = creat(fname,0);
        }
        if (fd<0) {
                printf("Can't create %s\n",fname);
                if (unlink(fname)==0) {
                        printf("because of previous typescript bomb - try again\n");
                }
                fail();
        }

        chmod(fname,0); /* in case it already exists */
        fixtty();
        if (!qflg) {
                printf("Script started, file is %s\n",fname);
                check(write(fd,"Script started on ",18));
                time(&tvec);
                check(write(fd,ctime(&tvec),25));
        }
        pipe(inpipe);
        pipe(outpipe);

        forkval = fork();
        if (forkval < 0)
                goto ffail;
        if (forkval == 0) {
                forkval = fork();
                if (forkval < 0)
                        goto ffail;
                if (forkval == 0)
                        dooutput();
                forkval = fork();
                if (forkval < 0)
                        goto ffail;
                if (forkval == 0)
                        doinput();
                doshell();
        }
        close(inpipe[0]); close(inpipe[1]);
        close(outpipe[0]); close(outpipe[1]);
        signal(SIGINT, SIG_IGN);
        signal(SIGQUIT, done);
        wait(&status);
        done();
        /*NOTREACHED*/

ffail:
        printf("Fork failed. Try again.\n");
        fail();
}

/* input process - copy tty to pipe and file */
doinput()
{

        signal(SIGINT, SIG_IGN);
        signal(SIGQUIT, SIG_IGN);
        signal(SIGTSTP, SIG_IGN);

        close(inpipe[0]);
        close(outpipe[0]);
        close(outpipe[1]);

        /* main input loop - copy until end of file (ctrl D) */
        while ((n=read(0,buffer,256)) > 0) {
                check(write(fd,buffer,n));
                write(inpipe[1],buffer,n);
        }

        /* end of script - close files and exit */
        close(inpipe[1]);
        close(fd);
        done();
}

/* do output process - copy to tty & file */
dooutput()
{

        signal(SIGINT, flsh);
        signal(SIGQUIT, SIG_IGN);
        signal(SIGTSTP, SIG_IGN);
        close(0);
        close(inpipe[0]);
        close(inpipe[1]);
        close(outpipe[1]);

        /* main output proc loop */
        while (n=read(outpipe[0],buffer,256)) {
                if (n > 0) { /* -1 means trap to flsh just happened */
                        write(1,buffer,n);
                        check(write(fd,buffer,n));
                }
        }

        /* output sees eof - close files and exit */
        if (!qflg) {
                printf("Script done, file is %s\n",fname);
                check(write(fd,"\nscript done on ",16));
                time(&tvec);
                check(write(fd,ctime(&tvec),25));
        }
        close(fd);
        exit(0);
}

/* exec shell, after diverting std input & output */
doshell()
{

        close(0);
        dup(inpipe[0]);
        close(1);
        dup(outpipe[1]);
        close(2);
        dup(outpipe[1]);

        /* close useless files */
        close(inpipe[0]);
        close(inpipe[1]);
        close(outpipe[0]);
        close(outpipe[1]);
        execl(shell, "sh", "-i", 0);
        execl(STDSHELL, "sh", "-i", 0);
        execl(NEWSHELL, "sh", "-i", 0);
        printf("Can't execute shell\n");
        fail();
}

fixtty()
{

        fstat(2, &sbuf);
        mode = sbuf.MODE&0777;
        chmod(tty, 0600);
}

/* come here on rubout to flush output - this doesn't work */
flsh()
{

        signal(SIGINT, flsh);
        /* lseek(outpipe[0],0l,2);      /* seeks on pipes don't work !"$"$!! */
}

fail()
{

        unlink(fname);
        kill(0, 15);    /* shut off other script processes */
        done();
}

done()
{

        chmod(tty, mode);
        chmod(fname, 0664);
        exit();
}

#ifndef V7ENV
#ifndef CC
char *ttyname(i) int i; {
        char *string;
        string = "/dev/ttyx";
        string[8] = ttyn(fd);
        if (string[8] == 'x') return((char *) (-1));
                else return(string);
}
#endif
#endif

check(n)
int n;
{
        /* checks the result of a write call, if neg
           assume ran out of disk space & die */
        if (n < 0) {
                write(1,"Disk quota exceeded - script quits\n",35);
                kill(0,15);
                done();
        }
}