source: trunk/minix/commands/yap/main.c@ 15

/* Copyright (c) 1985 Ceriel J.H. Jacobs */

# ifndef lint
static char rcsid[] = "$Header: /cvsup/minix/src/commands/yap/main.c,v 1.1.1.1 2005/04/21 14:55:40 beng Exp $";
# endif

# define _MAIN_

# include "in_all.h"
# if USG_OPEN
# include <fcntl.h>
# endif
# if BSD4_2_OPEN
# include <sys/file.h>
# endif
# if POSIX_OPEN
# include <sys/types.h>
# include <fcntl.h>
# endif
# include "main.h"
# include "term.h"
# include "options.h"
# include "output.h"
# include "process.h"
# include "commands.h"
# include "display.h"
# include "prompt.h"

char    *strcpy();

STATIC int initialize();
# ifdef SIGTSTP
STATIC int suspsig();
# endif

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

        register char ** av;

        if (! isatty(1)) {
                no_tty = 1;
        }
        argv[argc] = 0;
        progname = argv[0];
        if ((av = readoptions(argv)) == (char **) 0 ||
                initialize(*av ? 1 : 0)) {
                if (no_tty) {
                        close(1);
                        (VOID) dup(2);
                }
                putline("Usage: ");
                putline(argv[0]);
                putline(
" [-c] [-u] [-n] [-q] [-number] [+command] [file ... ]\n");
                flush();
                exit(1);
        }
        if (no_tty) {
                *--av = "cat";
                execve("/bin/cat", av, (char *) 0);
        }
        else    processfiles(argc-(av-argv), av);
        (VOID) quit();
        /* NOTREACHED */
}

char *mktemp();

/*
 * Open temporary file for reading and writing.
 * Panic if it fails
 */

static char indexfile[30], tempfile[30];

int
opentemp(i) {

        register fildes;
        register char *f;

        f = i ? mktemp(indexfile) : mktemp(tempfile);
# if BSD4_2_OPEN || USG_OPEN || POSIX_OPEN
        if ((fildes = open(f,O_RDWR|O_TRUNC|O_CREAT,0600)) < 0) {
# else
        if ((fildes = creat(f,0600)) <= 0 || close(fildes) < 0 ||
            (fildes = open(f,2)) < 0) {
# endif
                panic("Couldn't open temporary file");
        }
        (VOID) unlink(f);
        return fildes;
}

/*
 * Collect initializing stuff here.
 */

STATIC int
initialize(x) {

        if (!(nopipe = x)) {
                /*
                 * Reading from pipe
                 */
                if (isatty(0)) {
                        return 1;
                }
                stdf = dup(0);  /* Duplicate file descriptor of input */
                if (no_tty) return 0;
                /*
                 * Make sure standard input is from the terminal.
                 */
                (VOID) close(0);
# if BSD4_2_OPEN || USG_OPEN || POSIX_OPEN
                if (open("/dev/tty",O_RDONLY,0) != 0) {
# else
                if (open("/dev/tty",0) != 0) {
# endif
                        putline("Couldn't open terminal\n");
                        flush();
                        exit(1);
                }
        }
        if (no_tty) return 0;
        (VOID) strcpy(tempfile,"/usr/tmp/yap_XXXXXX");
        (VOID) strcpy(indexfile,"/usr/tmp/yap-XXXXXX");
        /*
         * Handle signals.
         * Catch QUIT, DELETE and ^Z
         */
        (VOID) signal(SIGQUIT,SIG_IGN);
        (VOID) signal(SIGINT, catchdel);
        ini_terminal();
# ifdef SIGTSTP
        if (signal(SIGTSTP,SIG_IGN) == SIG_DFL) {
                (VOID) signal(SIGTSTP,suspsig);
        }
# endif
        (VOID) signal(SIGQUIT,quit);
        return 0;
}

int
catchdel() {
        (VOID) signal(SIGINT, catchdel);
        interrupt = 1;
}

# ifdef SIGTSTP

/*
 * We had a SIGTSTP signal.
 * Suspend, by a call to this routine.
 */

VOID
suspend() {

        nflush();
        resettty();
        (VOID) signal(SIGTSTP,SIG_DFL);
#if BSD4_2_OPEN
        sigsetmask(sigblock(0)&~(1 << (SIGTSTP - 1)));
#endif
        (VOID) kill(0, SIGTSTP);
        /*
         * We are not here anymore ...
         *

         *
         * But we arive here ...
         */
        inittty();
        putline(TI);
        flush();
        (VOID) signal(SIGTSTP,suspsig);
}

/*
 * SIGTSTP signal handler.
 * Just indicate that we had one, ignore further ones and return.
 */

STATIC int
suspsig() {

        suspend();
        if (DoneSetJmp) longjmp(SetJmpBuf, 1);
}
# endif

/*
 * quit : called on exit.
 * I bet you guessed that much.
 */

int
quit() {

        clrbline();
        resettty();
        flush();
        exit(0);
}

/*
 * Exit, but nonvoluntarily.
 * At least tell the user why.
 */

VOID
panic(s) char *s; {

        putline("\007\007\007\r\n");
        putline(s);
        putline("\r\n");
        quit();
}