minnie.tuhs.org/unixen.tar/unixen/PDP-11/Distributions/ucb/spencer_2bsd.tar.gz/2bsd.tar/src/pi/main.c

C/C++ Source or Header | 1980-02-17 | 4.4 KB | 251 lines

/* Copyright (c) 1979 Regents of the University of California */
#
/*
 * pi - Pascal interpreter code translator
 *
 * Charles Haley, Bill Joy UCB
 * Version 1.2 January 1979
 */

#include "0.h"

/*
 * This version of pi has been in use at Berkeley since May 1977
 * and is very stable, except for the syntactic error recovery which
 * has just been written.  Please report any problems with the error
 * recovery to the second author at the address given in the file
 * READ_ME.  The second author takes full responsibility for any bugs
 * in the syntactic error recovery.
 */

char    piusage[]    "pi [ -blnpstuw ] [ -i file ... ] name.p";
char    pixusage[]    "pix [ -blnpstuw ] [ -i file ... ] name.p [ arg ... ]";

char    *usageis    piusage;
char    *obj        "obj";
/*
 * Be careful changing errfile and howfile.
 * There are the "magic" constants 9 and 15 immediately below.
 */
char    *errfile    "/usr/lib/pi1.2strings";
char    *howfile    "/usr/lib/how_pi\0";

int    onintr();

extern    int ibuf[259];

extern    char *lastname;

/*
 * Main program for pi.
 * Process options, then call yymain
 * to do all the real work.
 */
main(argc, argv)
    int argc;
    char *argv[];
{
    register char *cp;
    register c;
    int i;

    if (argv[0][0] == 'a')
        errfile =+ 9, howfile =+ 9;
    if (argv[0][0] == '-' && argv[0][1] == 'o') {
        obj = &argv[0][2];
        usageis = pixusage;
        howfile[15] = 'x';
        ofil = 3;
    } else {
        ofil = creat(obj, 0755);
        if (ofil < 0) {
            perror(obj);
            pexit(NOSTART);
        }
    }
    argv++, argc--;
    if (argc == 0) {
        i = fork();
        if (i == -1)
            goto usage;
        if (i == 0) {
            execl("/bin/cat", "cat", howfile, 0);
            goto usage;
        }
        while (wait(&i) != -1)
            continue;
        pexit(NOSTART);
    }
    opt('p') = opt('t') = opt('b') = 1;
    while (argc > 0) {
        cp = argv[0];
        if (*cp++ != '-')
            break;
        while (c = *cp++) switch (c) {
#ifdef DEBUG
            case 'c':
            case 'r':
            case 'y':
                togopt(c);
                continue;
            case 'C':
                yycosts();
                pexit(NOSTART);
            case 'A':
                testtrace++;
            case 'F':
                fulltrace++;
            case 'E':
                errtrace++;
                opt('r')++;
                continue;
            case 'U':
                yyunique = 0;
                continue;
#endif
            case 'b':
                opt('b') = 2;
                continue;
            case 'i':
                pflist = argv + 1;
                pflstc = 0;
                while (argc > 1) {
                    if (dotted(argv[1], 'p'))
                        break;
                    pflstc++, argc--, argv++;
                }
                if (pflstc == 0)
                    goto usage;
                continue;
            case 'l':
            case 'n':
            case 'p':
            case 's':
            case 't':
            case 'u':
            case 'w':
                togopt(c);
                continue;
            case 'z':
                monflg++;
                continue;
            default:
usage:
                Perror( "Usage", usageis);
                pexit(NOSTART);
        }
        argc--, argv++;
    }
    if (argc != 1)
        goto usage;
    efil = open(errfile, 0);
    if (efil < 0)
        perror(errfile), pexit(NOSTART);
    filename = argv[0];
    if (!dotted(filename, 'p')) {
        Perror(filename, "Name must end in '.p'");
        pexit(NOSTART);
    }
    close(0);
    if (fopen(filename, ibuf) < 0)
        perror(filename), pexit(NOSTART);
    if ((signal(2, 1) & 01) == 0)
        signal(2, onintr);
    if (opt('l')) {
        opt('n')++;
        yysetfile(filename);
        opt('n')--;
    } else
        lastname = filename;
    yymain();
    /* No return */
}

/*
 * Buffer for putchar
 */
char    pcbuf[128];
char    *pcbp pcbuf;

/*
 * Line buffered putchar for pi.
 */
putchar(c)
    char c;
{

    *pcbp++ = c;
    if (c == '\n' || pcbp == &pcbuf[sizeof pcbuf-1]) {
        write(1, &pcbuf, pcbp-pcbuf);
        pcbp = pcbuf;
    }
}

char    ugh[]    "Fatal error in pi\n";
/*
 * Exit from the Pascal system.
 * We throw in an ungraceful termination
 * message if c > 1 indicating a severe
 * error such as running out of memory
 * or an internal inconsistency.
 */
pexit(c)
    int c;
{

    if (opt('l') && c != DIED && c != NOSTART)
        while (getline() != -1)
            continue;
    yyflush();
    switch (c) {
        case DIED:
            write(2, ugh, sizeof ugh);
        case NOSTART:
        case ERRS:
            if (ofil > 0)
                unlink(obj);
            break;
        case AOK:
            pflush();
            break;
    }
    if (fork() == 0) {
        char *cp = "-0";
        cp[1] += c;
        execl("/usr/lib/gather", "gather", cp, filename, 0);
        exit(1);
    }
    exit(c);
}

onintr()
{

    signal(2, 1);
    pexit(NOSTART);
}

/*
 * Get an error message from the error message file
 */
geterr(seekpt, buf)
    int seekpt;
    char *buf;
{

    if (seek(efil, seekpt, 0) || read(efil, buf, 256) <= 0)
        perror(errfile), pexit(DIED);
}

header()
{
    extern char version[];
    static char anyheaders;

    gettime();
    if (anyheaders && opt('n'))
        putchar('\f');
    anyheaders++;
    printf("Berkeley Pascal PI -- Version 1.2 (%s)\n\n%s  %s\n\n", version, myctime(tvec), filename);
}