usr/src/usr.bin/pascal/px/int.c

/*-
 * Copyright (c) 1980 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. 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.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1980 The Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)int.c       5.3 (Berkeley) 4/16/91";
#endif /* not lint */

/*
 * px - interpreter for Berkeley Pascal
 * Version 3.0 Winter 1979
 *
 * Original version for the PDP 11/70 authored by:
 * Bill Joy, Charles Haley, Ken Thompson
 *
 * Rewritten for VAX 11/780 by Kirk McKusick
 */

#include        <signal.h>
#include        "whoami.h"
#include        "vars.h"
#include        "libpc.h"
#include        "objfmt.h"

/*
 * New stuff for pdx
 */

extern char *end;
extern loopaddr();
extern union progcntr pdx_pc;   /* address of interpreter program cntr */
static void inittrap();

main(ac,av)

        int     ac;
        char    **av;

{
        register char *objprog, *file;
        char *name;
        register long bytesread, bytestoread, block;
        register FILE *prog;
        struct   pxhdr pxhd;
#       define   pipe 3

        /*
         * Initialize everything
         */
        _argc = ac;
        _argv = av;
        _nodump = FALSE;
\f
        /*
         * Determine how PX was invoked, and how to process the program
         */
        file = _argv[1];
        if (!strcmp(_argv[0], "pdx")) {
                _mode = PDX;
                _argv += 2; _argc -= 2;
                name = _argv[0];
        } else if (!strcmp(_argv[0], "pix")) {
                _mode = PIX;
                _argv++; _argc--;
                name = _argv[0];
        } else if (!strcmp(_argv[0], "pipe")) {
                _mode = PIPE;
                file = "PIPE";
                _argv++; _argc--;
                name = _argv[0];
        } else {
                _mode = PX;
                if (_argc <= 1)
                        file = "obj";
                name = file;
        }
\f
        /*
         * kludge to check for old style objs.
         */
        if (_mode == PX && !strcmp(file, "-")) {
                fprintf(stderr, "%s is obsolete and must be recompiled\n",
                    _argv[0]);
                exit(1);
        }
        /*
         * Process program header information
         */
        if (_mode == PIPE) {
                read(pipe,&pxhd,sizeof(struct pxhdr));
        } else {
                prog = fopen(file,"r");
                if (prog == NULL) {
                        perror(file);
                        exit(1);
                }
                fread(&pxhd,sizeof(struct pxhdr),1,prog);
                if (pxhd.magicnum != MAGICNUM) {
                        fseek(prog,(long)(HEADER_BYTES-sizeof(struct pxhdr)),0);
                        fread(&pxhd,sizeof(struct pxhdr),1,prog);
                }
        }
        if (pxhd.magicnum != MAGICNUM) {
                fprintf(stderr,"%s is not a Pascal interpreter file\n",name);
                exit(1);
        }
        if (pxhd.maketime < createtime) {
                fprintf(stderr,"%s is obsolete and must be recompiled\n",name);
                exit(1);
        }
\f
        /*
         * Load program into memory
         */
        objprog = malloc((int)pxhd.objsize);
        if (_mode == PIPE) {
                bytestoread = pxhd.objsize;
                bytesread = 0;
                do      {
                        block = read(pipe,(int)(objprog+bytesread),bytestoread);
                        if (block > 0) {
                                bytesread += block;
                                bytestoread -= block;
                        }
                } while (block > 0);
        } else {
                bytesread = fread(objprog,1,(int)pxhd.objsize,prog);
                fclose(prog);
        }
        if (bytesread != pxhd.objsize) {
                fprintf(stderr,"Read error occurred while loading %s\n",file);
                exit(1);
        }
        if (_mode == PIX)
                fputs("Execution begins...\n",stderr);
        /*
         * set interpreter to catch expected signals and begin interpretation
         */
        signal(SIGILL,syserr);
        signal(SIGBUS,syserr);
        signal(SIGSYS,syserr);
        if (signal(SIGINT,SIG_IGN) != SIG_IGN)
                signal(SIGINT,intr);
        signal(SIGSEGV,memsize);
        signal(SIGFPE,EXCEPT);
        signal(SIGTRAP,liberr);

        /*
         * See if we're being watched by the debugger, if so set a trap.
         */
        if (_mode == PDX || (_mode == PIX && pxhd.symtabsize > 0)) {
                inittrap(&_display, &_dp, objprog, &pdx_pc, loopaddr);
        }

        /*
         * do it
         */
        interpreter(objprog);
        /*
         * reset signals, deallocate memory, and exit normally
         */
        signal(SIGINT,SIG_IGN);
        signal(SIGSEGV,SIG_DFL);
        signal(SIGFPE,SIG_DFL);
        signal(SIGTRAP,SIG_DFL);
        signal(SIGILL,SIG_DFL);
        signal(SIGBUS,SIG_DFL);
        signal(SIGSYS,SIG_DFL);
        PFLUSH();
        psexit(0);
}

/*
 * Generate an IOT trap to tell the debugger that the object code
 * has been read in.  Parameters are there for debugger to look at,
 * not the procedure.
 */

static void
inittrap(dispaddr, dpaddr, endaddr, pcaddr, loopaddrp)
union disply *dispaddr;
struct disp *dpaddr;
char *endaddr;
union progcntr *pcaddr;
char **loopaddrp;
{
        kill(getpid(), SIGIOT);
}