xref: /csrg-svn/usr.bin/pascal/pdx/process/start.c (revision 5653)

/* Copyright (c) 1982 Regents of the University of California */

static char sccsid[] = "@(#)start.c 1.2 02/02/82";

/*
 * Begin execution.
 *
 * For px, pstart does a traced exec to read in px and then stop.  But we
 * want control after px has read in the obj file and before it starts
 * executing.  The zeroth argument to px tells it to give us control
 * by sending itself a signal just prior to interpreting.
 *
 * We set a "END_BP" breakpoint at the end of the code so that the
 * process data doesn't disappear after the program terminates.
 */

#include "defs.h"
#include <signal.h>
#include "process.h"
#include "machine.h"
#include "main.h"
#include "breakpoint.h"
#include "source.h"
#include "object.h"
#include "mappings.h"
#include "sym.h"
#include "process.rep"

#	if (isvaxpx)
#		include "pxinfo.h"
#	endif

LOCAL PROCESS pbuf;

start(argv, infile, outfile)
char **argv;
char *infile, *outfile;
{
	char *cmd;

	process = &pbuf;
	setsigtrace();
#	if (isvaxpx)
		cmd = "px";
#	else
		cmd = argv[0];
#	endif
	pstart(process, cmd, argv, infile, outfile);
	if (process->status == STOPPED) {
#		if (isvaxpx)
			TRAPARGS *ap, t;

			pcont(process);
			if (process->status != STOPPED) {
				if (option('t')) {
					quit(process->exitval);
				} else {
					panic("px exited with %d", process->exitval);
				}
			}
			dread(&ap, process->fp + 2*sizeof(int), sizeof(ap));
			dread(&t, ap, sizeof(TRAPARGS));
			if (t.nargs != 5) {
				if (option('t')) {
					unsetsigtraces(process);
					pcont(process);
					quit(process->exitval);
				} else {
					panic("start: args out of sync");
				}
			}
			DISPLAY = t.disp;
			DP = t.dp;
			ENDOFF = t.objstart;
			PCADDRP = t.pcaddrp;
			LOOPADDR = t.loopaddr;
#		endif
		pc = 0;
		curfunc = program;
		if (objsize != 0) {
			addbp(lastaddr(), END_BP, NIL, NIL, NIL, 0);
		}
	} else {
		panic("could not start program");
	}
}

/*
 * Note the termination of the program.  We do this so as to avoid
 * having the process exit, which would make the values of variables
 * inaccessible.
 *
 * Although the END_BP should really be deleted, it is taken
 * care of by fixbps the next time the program runs.
 */

endprogram()
{
	char *filename;

	if (ss_variables) {
		prvarnews();
	}
	printf("\nexecution completed\n");
	curfunc = program;
	if ((filename = srcfilename(pc)) != cursource) {
		skimsource(filename);
	}
	curline = lastlinenum;
	erecover();
}

/*
 * set up what signals we want to trace
 */

LOCAL setsigtrace()
{
	register int i;
	register PROCESS *p;

	p = process;
	for (i = 1; i < NSIG; i++) {
		psigtrace(p, i, TRUE);
	}
	psigtrace(p, SIGHUP, FALSE);
	psigtrace(p, SIGKILL, FALSE);
}