#include        "ass00.h"
#include        "assex.h"

/*
 * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
 * See the copyright notice in the ACK home directory, in the file "Copyright".
 *
 */

#ifndef NORCSID
static char rcs_id[] = "$Id$" ;
#endif

/*
** Main routine of EM1-assembler/loader
*/

main(argc, argv)
	int     argc;
	char    **argv;
{
	/*
	 * Usage: ass [-[d][p][m][u][U]] [-s(s/m/l/x)] [ [file] [flag] ] ...
	 *   The d flag can be repeated several times, resulting in more
	 *        debugging information.
	 */
	char workspace[6000] ;
	register char *cp ;
	register int argno ;

	progname = argv[0];
	for ( cp=argv[0] ; *cp ; ) if ( *cp++ == '/' ) progname= cp;
	for ( argno=1 ; argno<argc ; argno++ ) {
		if ( argv[argno][0] == '-' && LC(argv[argno][1]) == 's') {
			getsizes(&argv[argno][2]);
			break ;
		}
	}
	/* A piece of the interpreter's stack frame is used as
	   free area initially */
	freearea( (area_t) workspace, (unsigned) sizeof workspace ) ;
	getcore();
	init_files();
	init_vars();
	while ( --argc )
		argument(*++argv);
	finish_up();
	exit(nerrors!=0);
}

getcore() {
	register siz_t *p;
	siz_t bytes;
	register unsigned n ;
	register char *base ;

	/*
	 * xglobs[] should be located in front of mglobs[], see upd_reloc()
	 */

	p = oursize; n = 0;
	n += (bytes.n_glab = p->n_glab * (sizeof *xglobs));
	n += (bytes.n_mlab = p->n_mlab * (sizeof *mglobs));
	n += (bytes.n_mproc = p->n_mproc * (sizeof *mprocs));
	n += (bytes.n_xproc = p->n_xproc * (sizeof *xprocs));
	n += (bytes.n_proc = p->n_proc * (sizeof *proctab));
	base = getarea(n);
	zero(base,n);
	xglobs = gbp_cast base; base += bytes.n_glab;
	mglobs = gbp_cast base; base += bytes.n_mlab;
	mprocs = prp_cast base; base += bytes.n_mproc;
	xprocs = prp_cast base; base += bytes.n_xproc;
	proctab = ptp_cast base; base += bytes.n_proc;
}

getsizes(str) char *str; {

	/*
	 * accepts -ss (small), -sm (medium), -sl (large), -sx (extra large)
	 */

	switch(LC(*str)) {
		default:error("bad size option %s",str);
	case 's':       oursize = &sizes[0]; break;
	case 'm':       oursize = &sizes[1]; break;
	case 'l':       oursize = &sizes[2]; break;
	case 'x':	oursize = &sizes[3]; break;
	}
}

char oflag;

argument(arg) char *arg; {
	register w;

	/*
	 * This routine decides what to do with each argument.
	 * It recognises flags and modules.
	 * Furthermore, it knows a library when it sees it and
	 * call archive() to split it apart.
	 */

	if (oflag) {
		eout = arg;
		oflag=0;
		return;
	}
	if(*arg == '-') {
		flags(arg);
		return;
	}
	curfile = arg;  /* for error messages etc. */
	if ((ifile = fopen(arg,"r")) == 0) {
		error("can't open %s",arg);
		return;
	}
	inpoff = 2;
	if ((w = getu16()) == sp_magic )
		read_compact();
	else if (w == ARMAG || w == AALMAG) {
		archmode = TRUE;
		archive();
		archmode = FALSE;
	} else
		error("%s: bad format",arg);
	if (fclose(ifile) == EOF)
		;
}

/*
** process flag arguments
*/

static int memflg ;

flags(arg)
	char    *arg;
{
	register char   *argp;
	register on;

	argp = arg;
	while (*++argp)
	{
		switch(LC(*argp))
		{
			case 'd':       d_flag++;break;
			case 'r':       r_flag++;break;
			case 's':       return ; /* s-flag is already scanned */
#ifdef MEMUSE
			case 'm':       memflg++ ; break ;
#endif
			case 'p':       ++procflag;break;
#ifdef DUMP
			case 'u':       ++c_flag;break;
#endif
			case 'o':       ++oflag; break;
			case 'w':       ++wflag; break;
#ifdef JOHAN
			case 'j':       ++jflag; break;
#endif
			case 'U':	++Uflag; break;
			case '-':
			case '+':
				on = (*argp == '+');
				while (*++argp) switch(LC(*argp)) {
				case 't': if (on) intflags |= 01;
					  else intflags &= ~01;
					  break;
				case 'p': if (on) intflags |= 02;
					  else intflags &= ~02;
					  break;
				case 'f': if (on) intflags |= 04;
					  else intflags &= ~04;
					  break;
				case 'c': if (on) intflags |= 010;
					  else intflags &= ~010;
				case 'e': if (on) intflags |= 040;
					  else intflags &= ~040;
					  break;
				default:
				  error("bad interpreter option %s",argp);
				}
				--argp;
				break;
			default:
				error("bad flag %s",argp);
					break;
		}
	}
}

do_proc() {
	/* One procedure has been read and will be processed.
	 *
	 * NOTE: The numbers of the passes, 1 3 4 and 5, are a remainder
	 *       of ancient times.
	 */

	dump(1); if ( memflg>2 )memuse();
	pass_3();  dump(3);
	pass_4();  dump(4);
	pass_5();  if ( memflg>2 ) memuse() ;
	endproc();  if ( memflg>1 ) memuse() ;
}

archive() {
	register i;
	register char *p;

	/*
	 * Read a library.
	 * The format of the libary used is that of a UNIX/V7(PDP)-archive.
	 *
	 * NOTE: If it was allowed for an archive to contain
	 *       obligatory modules as well as optionals,
	 *       it would not be possible to speed up things a bit
	 *       by stopping when all references are resolved.
	 *       This is the only reason.
	 */

	for(;;) {
		if (unresolved == 0) {  /* no use for this library anymore */
			return;
		}
		p = chp_cast &archhdr;
		if ((i = fgetc(ifile))==EOF ) {
			return;
		}
		*p++ = i;
		for (i=1;i< sizeof archhdr.ar_name; i++)
			*p++ = get8();
		for (i=0;i<8;i++) get8();
		archhdr.ar_size= ((long)get16()<<16) ;
		archhdr.ar_size+= getu16();
		inpoff = 0;     libeof = archhdr.ar_size;
		/*
		 * UNIX archiveheader is read now, now process the contents
		 * of it. Note that recursive archives are not implemented.
		 *
		 * The variable libeof is used by get8() to check
		 * whether or not we try to pass the library-boundary.
		 */
		if ( getu16() == sp_magic ) {
			read_compact();
		} else
			error("bad archive entry");
		skipentry();
		libeof = 0;
	}       /* up to the next entry */
}

skipentry() {

	/*
	 * for some reason the rest of this library entry needs to be
	 * skipped. Do that now.
	 */
	while(inpoff<libeof)
		get8();
	if(odd(libeof))                 /* archive entries are evensized */
		if (fgetc(ifile) == EOF)   /* except maybe the last one */
			;
}

init_vars() {

	/*
	 * A small collection of variables is initialized.
	 * This occurs only for those that couldn't be initialized
	 * at compile-time.
	 */

}

init_files() {

	/*
	 * The temporary files on which text and data are kept
	 * during assembly are set up here.
	 */
#ifdef CPM
	unlink("????????.$$$");
	tfile=fopen("TFILE.$$$", "w");
	dfile=fopen("DFILE.$$$", "w");
	rtfile=fopen("RTFILE.$$$", "w");
	rdfile=fopen("RDFILE.$$$", "w");
#else
	/*
	 * The function tmpfil() returns a file-descriptor
	 * of a file that is valid for reading and writing.
	 * It has the nice property of generating truly unique names.
	 */

	tfile=fdopen(tmpfil(),"w") ;
	dfile=fdopen(tmpfil(),"w") ;
	rtfile=fdopen(tmpfil(),"w") ;
	rdfile=fdopen(tmpfil(),"w") ;
#endif
}

initproc() {

	/*
	 * Called at the start of assembly of every procedure.
	 */

	stat_t *prevstate ;

	prevstate= pst_cast getarea(sizeof pstate) ;
	*prevstate= pstate ;
	pstate.s_prevstat= prevstate ;
	pstate.s_curpro= prp_cast 0 ;
	pstate.s_fline= lnp_cast 0 ;
	pstate.s_fdata= l_data ;
	pstate.s_locl = (locl_t (*)[])
		getarea(LOCLABSIZE * sizeof ((*(pstate.s_locl))[0]));
	zero(chp_cast pstate.s_locl,
		LOCLABSIZE * (unsigned) sizeof ((*(pstate.s_locl))[0]));
	if ( memflg>2 ) memuse() ;
}

endproc() {
	/* Throw the contents of the line and local label table away */
	register line_t *lnp1;
	register locl_t *lbhead,*lbp,*lbp_next;
	register kind ;
	register stat_t *prevstate;

	while ( lnp1= pstate.s_fline ) {
		pstate.s_fline= lnp1->l_next ;
		kind= lnp1->type1 ;
		if ( kind>VALLOW ) kind=VALLOW ;
		freearea((area_t)lnp1,(unsigned)linesize[kind]) ;
	}
	prevstate= pstate.s_prevstat ;
	if ( prevstate!= pst_cast 0 ) {
		for ( lbhead= *pstate.s_locl;
			lbhead<&(*pstate.s_locl)[LOCLABSIZE] ; lbhead++ ) {
			for ( lbp=lbhead->l_chain; lbp!= lbp_cast 0; lbp= lbp_next ) {
				lbp_next= lbp->l_chain;
				freearea((area_t)lbp,(unsigned)sizeof *lbp) ;
			}
		}
		freearea((area_t)(*pstate.s_locl),
			LOCLABSIZE * (sizeof((*pstate.s_locl)[0])));
		pstate= *prevstate ;
		freearea((area_t)prevstate,(unsigned)sizeof *prevstate) ;
	}
}

init_module() {

	/*
	 * Called at the start of every module.
	 */

	holbase  = 0;
	line_num = 1;
	mod_sizes = 0;
}

end_module() {

	/*
	 * Finish a module.
	 * Work to be done is mainly forgetting of local names,
	 * and remembering of those that will live during assembly.
	 */

	align(wordsize) ;
	set_mode(DATA_NUL);
	dump(100);
	enmd_pro();
	enmd_glo();
	if ( memflg ) memuse() ;
}

enmd_pro() {
	register proc_t *p,*limit;

	/*
	 * Check that all local procedures have been defined,
	 * and forget them immediately thereafter.
	 */

	limit = &mprocs[oursize->n_mproc];
	for (p=mprocs; p<limit; p++) {
		if (p->p_name == 0)
			continue;
		if ((p->p_status&DEF)==0)
			error("undefined local procedure '%s'",p->p_name);
	}
	zero(chp_cast mprocs,(limit-mprocs)* (unsigned)sizeof *mprocs);

	/* Clobber all flags indicating that external procedures
	 * were used in this module.
	 */

	limit = &xprocs[oursize->n_xproc];
	for (p=xprocs; p<limit; p++) {
		p->p_status &= ~EXT ;
	}
}

enmd_glo() {
	register glob_t *mg,*xg,*limit;

	/*
	 * Tougher then enmd_pro().
	 * Check all the symbols used in this module that are
	 * not to be forgotten immediately.
	 * A difficulty arises here:
	 *      In the tables textreloc[] and datareloc[]
	 *      pointers are used to identify the symbols concerned.
	 *      These pointers point into mglobs[].
	 *      Since at the end of assembly only the value of xglobs[]
	 *      is defined, these pointers have to be changed.
	 *      upd_reloc() takes care of this.
	 */

	limit = &mglobs[oursize->n_mlab];
	for ( mg = mglobs; mg < limit; mg++) {
		if (mg->g_name == 0)
			continue;
		if ((mg->g_status&(EXT|DEF))==0)
			error("undefined local symbol '%s'",glostring(mg));
		if ((mg->g_status&EXT)==0)
			continue;
		xg = xglolookup(mg->g_name,ENTERING);
		switch(xg->g_status&(EXT|DEF)) {
		case 0:         /* new symbol */
			if((mg->g_status&DEF)==0)
				++unresolved;
			break;
		case EXT:       /* already used but not defined */
			if(mg->g_status&DEF) {
				--unresolved;
			}
			break;
		}
		xg->g_status |= mg->g_status;
		if (mg->g_status&DEF)
			xg->g_val.g_addr = mg->g_val.g_addr;
		else
			mg->g_val.g_gp = xg;        /* used by upd_reloc */
	} /* up to the next symbol */
	upd_reloc();
	zero(chp_cast mglobs,(limit-mglobs)*(unsigned) sizeof *mglobs);
}

finish_up()
{
	/*
	 * Almost done. Check for unresolved references,
	 * make the e.out file and stop.
	 */

#ifdef DUMP
	c_print();
#endif
	check_def();
	if ( nerrors==0 ) copyout();
}

#ifdef DUMP
c_print() {
	if ( ! c_flag ) return ;
	c_dprint("primary",opcnt1) ;
	c_dprint("secondary",opcnt2) ;
	c_dprint("extra long",opcnt3) ;
}

c_dprint(str,cnt) char *str,*cnt ; {
	register int first,curr ;
	printf("unused %s opcodes\n",str) ;
	for ( first= -1 , curr=0 ; curr<=256 ; curr++ ) {
		if ( curr==256 || cnt[curr]  ) {
			if ( first!= -1 ) {
				if ( first+1 == curr ) {
					printf("%3d\n",first ) ;
				} else {
					printf("%3d..%3d\n",first,curr-1) ;
				}
				first= -1 ;
			}
		} else {
			if ( first== -1 ) first=curr ;
		}
	}
}
#endif

check_def() {
	register proc_t *p;
	register glob_t *g;
	register count;

	/*
	 * Check for unresolved references.
	 * NOTE: The occurring of unresolved references is not fatal,
	 *       although the use of the e.out file after this
	 *       occurring must be strongly discouraged.
	 *       Every use of the symbols concerned is undefined.
	 */

	if (unresolved) {
		printf("Unresolved references\n  Procedures:\n");
		count = oursize->n_xproc;
		for (p = xprocs; count--; p++)
			if (p->p_name && (p->p_status&DEF)==0)
				printf("    %s\n",p->p_name);
		printf("  Data:\n");
		count = oursize->n_glab;
		for (g = xglobs; count--; g++)
			if (g->g_name && (g->g_status&DEF)==0)
				printf("    %s\n",glostring(g));
		if (! Uflag) nerrors++;
	}
}

ertrap() { /* trap routine to drain input in case of compile errors */

	if (fileno(ifile)== 0)
		while (fgetc(ifile) != EOF)
			;
	exit(1);
}