/*	File:	main.c
 *
 *	Main entry to the linker.
 */


#include "link.h"
#include <signal.h>


extern	unsigned char	sourcename[];
extern	unsigned char	filename[];
extern	unsigned char	logname[];
extern	unsigned char	mapname[];
extern	unsigned char	objname[];
extern	unsigned char	gblname[];
extern	unsigned char	cmdline[];
extern	unsigned char	cname1[];
extern	unsigned char	cname2[];
extern	unsigned char	dateb[];
extern	unsigned char	timeb[];
extern	unsigned char	sdate[];
extern	unsigned char	sxtime[];
extern	unsigned char	line[];
extern	unsigned char	*who;
extern	unsigned char	cmdflag;
extern	unsigned char	passno;
extern	unsigned char	mode;
extern	unsigned int	log;
extern	unsigned int	noref;
extern	unsigned int	nosym;
extern	unsigned int	nopsect;
extern	unsigned int	noload;
extern	unsigned int	ltruncate;
extern	unsigned int	hex_value;
extern	unsigned int	cmdaddress;
extern	unsigned int	fullflag;
extern	unsigned int	cvalue1;
extern	unsigned int	cvalue2;
extern	unsigned int	relo[];
extern	unsigned int	adrefc[];
extern	unsigned int	ofset1;
extern	unsigned int	errcnt;
extern	unsigned int	warning;
extern	unsigned int	fatal;
extern	unsigned int	dataflag;
extern	unsigned int	lflag;
extern	unsigned int	slenth;
extern	FILE		*cmdfile;
extern	FILE		*logfile;
extern	FILE		*objfile;
extern	FILE		*mapfile;
extern	FILE		*infile;
extern	FILE		*datafile;

extern	char	*optarg;
extern	int	optind;

int		data_flag;
int		had_data;
unsigned char	*search();
unsigned char	*look();
unsigned char	*skipsp();
unsigned char	*move();
int		onintr();
int		Orecord = MAXOBJ;


static	unsigned char	*org_hold;
static	unsigned char	*org_save;
static	unsigned char	ctoken;
static	unsigned char	printbuff[100];
static	unsigned char	whoami[30];
static	unsigned int	deleteflag;
static	unsigned int	errorflag;
static	unsigned int	printflag;
static	unsigned int	mailflag;
static	unsigned int	ofirst;
static	unsigned int	dfirst;
static	unsigned int	parenflag;
static	unsigned int	expression;

FILE	*tryopen();
SYM	*locate();




main(argc, argv)
int argc;
char **argv;
{
	register unsigned char	*sp;
	register SYM		*xp;
	register int		c;
		 unsigned short	hold;
		 unsigned char	xbuff[50];


	slenth = 14;

	while((c = getopt(argc, argv, "lxsmafdepito:")) != EOF)
	{
		switch(c)
		{
		case 'l':
			log = 1;
			break;

		case 'x':
			noref = 1;
			break;

		case 's':
			nosym = 1;
			break;

		case 'm':
			nopsect = 1;
			break;

		case 'd':
			deleteflag = 1;

			break;

		case 'e':
			errorflag = 1;
			break;

		case 'p':
			printflag = 1;
			break;

		case 'i':
			mailflag = 1;
			break;

		case 't':
			ltruncate = 1;
			break;

		case 'S':
			slenth = atoi(optarg);
			break;

		case 'o':
			Orecord = atoi(optarg);

			if(Orecord < 8)
			{
				fprintf(stderr, "Illegal hex output length. Defaulting to 8\n");
				Orecord = 8;
			}
			else if(Orecord > MAXOBJ)
			{
				fprintf(stderr, "Illegal hex output length. Defaulting to %d\n", MAXOBJ);
				Orecord = MAXOBJ;
			}

			break;

		default:
			(void) fprintf(stderr, "Unknown option %c\n", c);
			break;
		}
	}

	if(deleteflag || errorflag)
		printflag = 1;


	if(signal(SIGINT, SIG_IGN) != SIG_IGN)
	{
		(void) signal(SIGINT, onintr);
		(void) signal(SIGQUIT, onintr);
		(void) signal(SIGHUP, onintr);
		(void) signal(SIGKILL, onintr);
	}

	gettime();
	(void) strcpy(sdate, dateb);
	(void) strcpy(sxtime, timeb);
	(void) strcpy(whoami, getenv("USER"));
	(void) strcpy(filename, argv[optind]);
	(void) strcpy(sourcename, look(filename));
	makelower(sourcename);

	if(sp = search(sourcename))
		*sp = 0;

	force_extension(sourcename, mapname, ".map");
	force_extension(sourcename, objname, ".hex");
	force_extension(sourcename, logname, ".log");
	force_extension(sourcename, gblname, ".gbl");
	objfile = fopen(objname, "w+");

	if(noref || nosym || nopsect)
		mapfile = fopen(mapname, "w+");

	if(log)
		logfile = fopen(logname, "w+");


	if(sp = search(filename))
		cmdflag = equal(++sp, "cmd");
	else
	{
		cmdflag = 1;
		addext(filename, ".cmd");
	}

	hold = 0;
	data_flag = -1;


	for(passno = 1; passno < 3; passno++)
	{
		adrefc[CSEG] = BASE_ADDRESS;
		relo[CSEG] = BASE_ADDRESS;
		adrefc[DSEG] = hold;
		relo[DSEG] = hold;
		mode = CSEG;
		ofset1 = 0;
		lflag = 0;
		ofirst = 0;
		dfirst = 0;
		errcnt = 0;
		fatal = 0;
		warning = 0;
		openr();
		clsrec();

		if(cmdflag)
		{
			if((cmdfile = tryopen(filename)) == 0)
			{
				printl("Can't open command file: %s\n", filename);
				xdone(1);
			}


			while(parse())
			{
				switch(ctoken)
				{
				case ORG_TOKEN:
					printl("CODE:\t%04.4X", cvalue1);

					if(expression)
					{
						org_hold[strlen(org_hold) - 1] = 0;
						printl("\t\t;%s", org_hold);
					}

					printl("\n");

					if(ofirst && (cvalue1 < adrefc[CSEG]))
						printl("Warning: new code segment overlaps old code segment\n");
					else
						++ofirst;

					adrefc[CSEG] = cvalue1;
					relo[CSEG] = cvalue1;
					lflag |= LADIS;
					break;

				case DATA_TOKEN:
					if(cvalue1 == 0)
						cvalue1 = adrefc[CSEG];

					printl("DATA:\t%04.4X", cvalue1);

					if(expression)
					{
						org_hold[strlen(org_hold) - 1] = 0;
						printl("\t\t;%s", org_hold);
					}

					printl("\n");

					if(dfirst && (cvalue1 < adrefc[DSEG]))
						printl("Warning: new data segment overlaps old data segment\n");
					else
						++dfirst;

					adrefc[DSEG] = cvalue1;
					relo[DSEG] = cvalue1;
					hold = cvalue1;
					data_flag = 0;
					break;

				case DUMMY:
				case LIST_TOKEN:
				case NAME_TOKEN:
				case FILL_TOKEN:
					continue;

				case INCLUDE_TOKEN:
					glink();
					break;

				case LOAD_TOKEN:
					include();
					break;

				case DPAGE_TOKEN:
					linkset(cvalue1);
					break;

				case END_TOKEN:
					if(passno == 2)
						traout(cvalue1, 0);

					goto done;

				case GLOBAL_TOKEN:
					printl("command file GLOBAL is NOT supported\n");
					printl("GLOBAL whatever labels you need in the source file(s)\n");
					continue;

				case DEFINE_TOKEN:
					if(passno == 1)
					{
						if(equal(cname1, "$"))
						{
							printl("Can't redefine the pc\n");
							continue;
						}
						else if(xp = locate(cname2))
						{
							if(xp->flag & LNKENT)
								printl("WARNING: value of %s being redefined\n", cname2);

							xp->value = cvalue2;
							xp->flag |= LNKENT;
						}
						else
							insert(cname2, cvalue2, LNKENT);

						printl("%s defined with value of %04.4X\n", cname2, cvalue2);
					}

					continue;

				default:
					printl("unknown operation: %s", cmdline);
					continue;
				}
			}
done:

			fclose(cmdfile);
		}
		else
		{
			addext(filename, ".rel");

			if((infile = tryopen(filename, "r")) == 0)
			{
				printl("Can't open main link file: %s\n", filename);
				xdone(1);
			}
			else
			{
				who = filename;
				fgetc(infile);	/* get the 'more' header  */
				fgetc(infile);	/* and throw it away	  */
				xlink();
			}

			fclose(infile);
		}

		if(had_data && data_flag)
		{
			cvalue1 = adrefc[CSEG];
			adrefc[DSEG] = cvalue1;
			relo[DSEG] = cvalue1;
			hold = cvalue1;
			data_flag = 0;
		}

		printl("Pass %d complete", passno);

		if(log)
		{
			gettime();
			printl(" at %s", timeb);
		}
	
		printl("\n");
	}

	dspmap();
	dspsym();
	dspref();

	if(errcnt)
		sprintf(xbuff, "%d", errcnt);
	else	sprintf(xbuff, "No");

	strcpy(line, mapfile ? "\n" : "");
	strcat(line, xbuff);
	strcat(line, " Link Error");

	if(errcnt != 1)
		strcat(line, "s");

	if(errcnt)
	{
		sprintf(xbuff, "\t%d Warnings, %d Fatal", warning, fatal);
		strcat(line, xbuff);
	}

	if(mapfile)
	{
		list(line);
		fclose(mapfile);
	}

	printl("%s\n", line);

	if (printflag && mapfile)
	{
		if (errorflag && errcnt)
		{
			printl("link: Listing NOT printed due to errors\n");
		}
		else
		{
			sprintf(printbuff, "lpr -X %s %s\n", deleteflag ? "-r" : "", mapname);
			system(printbuff);
		}
	}

	xdone(errcnt ? 1 : 0);
}



parse()
{
	register	unsigned char	*pnt;


	if(fgets(cmdline, 100, cmdfile) == 0)
	{
		printl("Unexpected EOF from command file\n");
		return(0);
	}

	cname1[0] = 0;
	cname2[0] = 0;
	cvalue1 = 0;
	cvalue2 = 0;
	ctoken = 0;
	expression = 0;
	pnt = move(skipsp(cmdline), cname1);

	if(*pnt == '\'')
		pnt = skipsp(++pnt);

	org_save = pnt;
	org_hold = pnt;

	if(isdigit(*pnt))
		cvalue1 = eval(pnt);
	else
	{
		pnt = move(pnt, cname2);
		strip(cname2);
	}


	if(equal(cname1, "org") || equal(cname1, "code"))
	{
		ctoken = ORG_TOKEN;
		cvalue1 = evaluate();
	}
	else if(equal(cname1, "data"))
	{
		ctoken = DATA_TOKEN;
		cvalue1 = evaluate();
	}
	else if(equal(cname1, "list"))
		ctoken = LIST_TOKEN;
	else if(equal(cname1, "name"))
		ctoken = NAME_TOKEN;
	else if((equal(cname1, "include")) || (equal(cname1, "includ")))
		ctoken = INCLUDE_TOKEN;
	else if(equal(cname1, "load"))
		ctoken = LOAD_TOKEN;
	else if(equal(cname1, "dpage"))
	{
		ctoken = DPAGE_TOKEN;

		if(equal(cname2, "P"))
			cvalue1 = 256;
		else
			cvalue1 = evaluate();
	}
	else if(equal(cname1, "end"))
	{
		ctoken = END_TOKEN;
		cvalue1 = evaluate(org_save);
	}
	else if(equal(cname1, "global"))
		ctoken = GLOBAL_TOKEN;
	else if(!cname1[0])
		ctoken = DUMMY;
	else if(cname1[0] == '*' || cname1[0] == '#')
		ctoken = DUMMY;
	else if(equal(cname1, "define"))
	{
		org_save = pnt;
		ctoken = DEFINE_TOKEN;
		cvalue2 = evaluate();
	}
	else if(equal(cname1, "fill"))
	{
		ctoken = FILL_TOKEN;
		noload = 1;
		hex_value = evaluate();
	}

	return(1);
}




unsigned char *move(from, to)
register unsigned char	*from, *to;
{
	while(*from > ' ')
		*to++ = *from++;

	*to = 0;

	return(skipsp(from));
}



eval(pointer)
register unsigned char	*pointer;
{
			unsigned char	c;
	register	unsigned int	value = 0;

	while(ishex(c = *pointer))
	{
		value *= 16;
		value += c > '9' ? c - '7' : c - '0';
		++pointer;
	}

	if(tolower(*pointer) == 'h')
		++pointer;

	return(value);
}




evaluate()
{
	register unsigned int	value, value1;
	register unsigned char	*bp, *xp;
	register SYM		*sp;
		 unsigned char	sbuff[100];


	value = 0;


	for(;;)
	{
		if(*org_save <= ' ' || *org_save == '\'' || *org_save > 'z')
			return(value);

		if(*org_save == ')')
		{
			if(!parenflag)
			{
				eprintf("No matching paren", org_save);
				++org_save;
				continue;
			}

			return(value);
		}


		if(isdigit(*org_save))
		{
			bp = sbuff;

			while(ishex(*org_save))
				*bp++ = *org_save++;

			if(tolower(*org_save) == 'h')
				++org_save;

			*bp = 0;
			value = eval(sbuff);
		}
		else if(an(*org_save))
		{
			if((org_save[0] == '$') && (!an(org_save[1])))
				goto current;

			bp = sbuff;
			xp = org_save;

			while(an(*org_save))
				*bp++ = *org_save++;

			*bp = 0;

			if(sp = locate(sbuff))
				value = sp->value;
			else
				eprintf("Undefined GLOBAL symbol", xp);
		}
		else
		{
current:
			switch(*org_save++)
			{
			case '(':
				++parenflag;
				value = evaluate();
				--parenflag;

				if(*org_save != ')')
					eprintf("Unbalanced parens", org_save);
				else
					++org_save;

				break;

			case '+':
				value += evaluate();
				break;

			case '-':
				value -= evaluate();
				break;

			case '/':
				value1 = evaluate();

				if(value1)
					value /= evaluate();
				else
					eprintf("Division by zero error", org_save);

				break;

			case '*':
				value *= evaluate();
				break;

			case '<':
				value <<= evaluate();
				break;

			case '>':
				value >>= evaluate();
				break;

			case '^':
				value ^= evaluate();
				break;

			case '|':
				value |= evaluate();
				break;

			case '&':
				value &= evaluate();
				break;

			case '$':
				value = adrefc[mode];
				break;

			default:
				eprintf("Unknown math operation", &org_save[-1]);
				continue;
			}

			expression = 1;
		}
	}
}



static eprintf(msg, pnt)
register unsigned char	*msg, *pnt;
{
	register	unsigned int	i;
			unsigned char	xbuff[200];


	i = 0;

	while(cmdline[i] && strcmp(&cmdline[i], pnt))
	{
		xbuff[i] = (cmdline[i] == '\t') ? '\t' : ' ';
		++i;
	}

	xbuff[i++] = '^';
	xbuff[i] = 0;
	printl("\n%s", cmdline);
	printl("%s\n", xbuff);
	printl("*** %s ***\n\n", msg);

	if(passno == 2)
	{
		++errcnt;
		++fatal;
	}
}




xdone(number)
{
	gettime();

	if (mailflag)
	{
		if (number)
			sprintf(printbuff, "Link of %s aborting abnormally during pass %u on: %s at: %s", filename, passno, dateb, timeb);
		else	sprintf(printbuff, "Link of %s complete with %u errors on: %s at: %s", filename, errcnt, dateb, timeb);
		mailit();
	}

	exit(number);
}






onintr(signo)
int	signo;
{
	if (signo == SIGQUIT)
		(void) signal(SIGQUIT, onintr);

	gettime();
	printl("\nLink interrupted on: %s at: %s\n", dateb, timeb);

	if (mailflag)
	{
		(void) sprintf(printbuff, "Link of %s interrupted on: %s at: %s\n", filename, dateb, timeb);
		mailit();
	}

	exit(1);
}




static mailit()
{
	char	mailbuf[200];

	(void) sprintf(mailbuf, "mail %s <<xx\n%s\nxx\n", whoami, printbuff);
	(void) system(mailbuf);
}