xref: /csrg-svn/usr.bin/pascal/src/fend.c (revision 7917)
1 /* Copyright (c) 1979 Regents of the University of California */
2 
3 static char sccsid[] = "@(#)fend.c 1.12 08/26/82";
4 
5 #include "whoami.h"
6 #include "0.h"
7 #include "tree.h"
8 #include "opcode.h"
9 #include "objfmt.h"
10 #include "align.h"
11 
12 /*
13  * this array keeps the pxp counters associated with
14  * functions and procedures, so that they can be output
15  * when their bodies are encountered
16  */
17 int	bodycnts[ DSPLYSZ ];
18 
19 #ifdef PC
20 #   include "pc.h"
21 #   include "pcops.h"
22 #endif PC
23 
24 #ifdef OBJ
25 int	cntpatch;
26 int	nfppatch;
27 #endif OBJ
28 
29 struct	nl *Fp;
30 int	pnumcnt;
31 /*
32  * Funcend is called to
33  * finish a block by generating
34  * the code for the statements.
35  * It then looks for unresolved declarations
36  * of labels, procedures and functions,
37  * and cleans up the name list.
38  * For the program, it checks the
39  * semantics of the program
40  * statement (yuchh).
41  */
42 funcend(fp, bundle, endline)
43 	struct nl *fp;
44 	int *bundle;
45 	int endline;
46 {
47 	register struct nl *p;
48 	register int i, b;
49 	int var, inp, out, *blk;
50 	bool chkref;
51 	struct nl *iop;
52 	char *cp;
53 	extern int cntstat;
54 #	ifdef PC
55 	    int		savlabel = getlab();
56 	    int		toplabel = getlab();
57 	    int		botlabel = getlab();
58 	    int		proflabel = getlab();
59 	    char	extname[ BUFSIZ ];
60 #	endif PC
61 
62 	cntstat = 0;
63 /*
64  *	yyoutline();
65  */
66 	if (program != NIL)
67 		line = program->value[3];
68 	blk = bundle[2];
69 	if (fp == NIL) {
70 		cbn--;
71 #		ifdef PTREE
72 		    nesting--;
73 #		endif PTREE
74 		return;
75 	}
76 #ifdef OBJ
77 	/*
78 	 * Patch the branch to the
79 	 * entry point of the function
80 	 */
81 	patch4(fp->value[NL_ENTLOC]);
82 	/*
83 	 * Put out the block entrance code and the block name.
84 	 * HDRSZE is the number of bytes of info in the static
85 	 * BEG data area exclusive of the proc name. It is
86 	 * currently defined as:
87 	/*	struct hdr {
88 	/*		long framesze;	/* number of bytes of local vars */
89 	/*		long nargs;	/* number of bytes of arguments */
90 	/*		bool tests;	/* TRUE => perform runtime tests */
91 	/*		short offset;	/* offset of procedure in source file */
92 	/*		char name[1];	/* name of active procedure */
93 	/*	};
94 	 */
95 #	define HDRSZE (2 * sizeof(long) + sizeof(short) + sizeof(bool))
96 	var = put(2, ((lenstr(fp->symbol,0) + HDRSZE) << 8)
97 		| (cbn == 1 && opt('p') == 0 ? O_NODUMP: O_BEG), (long)0);
98 	    /*
99 	     *  output the number of bytes of arguments
100 	     *  this is only checked on formal calls.
101 	     */
102 	put(2, O_CASE4, cbn == 1 ? (long)0 : (long)(fp->value[NL_OFFS]-DPOFF2));
103 	    /*
104 	     *	Output the runtime test mode for the routine
105 	     */
106 	put(2, sizeof(bool) == 2 ? O_CASE2 : O_CASE4, opt('t') ? TRUE : FALSE);
107 	    /*
108 	     *	Output line number and routine name
109 	     */
110 	put(2, O_CASE2, bundle[1]);
111 	putstr(fp->symbol, 0);
112 #endif OBJ
113 #ifdef PC
114 	/*
115 	 * put out the procedure entry code
116 	 */
117 	if ( fp -> class == PROG ) {
118 	    putprintf( "	.text" , 0 );
119 	    putprintf( "	.align	1" , 0 );
120 	    putprintf( "	.globl	_main" , 0 );
121 	    putprintf( "_main:" , 0 );
122 	    putprintf( "	.word	0" , 0 );
123 	    if ( opt ( 't' ) ) {
124 	        putprintf( "	pushl	$1" , 0 );
125 	    } else {
126 	        putprintf( "	pushl	$0" , 0 );
127 	    }
128 	    putprintf( "	calls	$1,_PCSTART" , 0 );
129 	    putprintf( "	movl	4(ap),__argc" , 0 );
130 	    putprintf( "	movl	8(ap),__argv" , 0 );
131 	    putprintf( "	calls	$0,_program" , 0 );
132 	    putprintf( "	pushl	$0" , 0 );
133 	    putprintf( "	calls	$1,_PCEXIT" , 0 );
134 	    ftnno = fp -> value[NL_ENTLOC];
135 	    putprintf( "	.text" , 0 );
136 	    putprintf( "	.align	1" , 0 );
137 	    putprintf( "	.globl	_program" , 0 );
138 	    putprintf( "_program:" , 0 );
139 	    stabfunc( "program" , fp -> class , bundle[1] , 0 );
140 	} else {
141 	    ftnno = fp -> value[NL_ENTLOC];
142 	    putprintf( "	.text" , 0 );
143 	    putprintf( "	.align	1" , 0 );
144 	    sextname( extname , fp -> symbol , cbn - 1 );
145 	    putprintf( "	.globl	%s%s" , 0 , FORMALPREFIX , extname );
146 	    putprintf( "	.globl	%s" , 0 , extname );
147 	    putprintf( "%s:" , 0 , extname );
148 	    stabfunc( fp -> symbol , fp -> class , bundle[1] , cbn - 1 );
149 	    for ( p = fp -> chain ; p != NIL ; p = p -> chain ) {
150 		stabparam( p -> symbol , p2type( p -> type )
151 			    , p -> value[ NL_OFFS ] , lwidth( p -> type ) );
152 	    }
153 	    if ( fp -> class == FUNC ) {
154 		    /*
155 		     *	stab the function variable
156 		     */
157 		p = fp -> ptr[ NL_FVAR ];
158 		stablvar( p -> symbol , p2type( p -> type ) , cbn
159 			, p -> value[ NL_OFFS ] , lwidth( p -> type ) );
160 	    }
161 		/*
162 		 *	stab local variables
163 		 *	rummage down hash chain links.
164 		 */
165 	    for ( i = 0 ; i <= 077 ; i++ ) {
166 		for ( p = disptab[ i ] ; p != NIL ; p = p->nl_next) {
167 		    if ( ( p -> nl_block & 037 ) != cbn ) {
168 			break;
169 		    }
170 		    /*
171 		     *	stab local variables
172 		     *	that's named variables, but not params
173 		     */
174 		    if (   ( p -> symbol != NIL )
175 			&& ( p -> class == VAR )
176 			&& ( p -> value[ NL_OFFS ] < 0 ) ) {
177 			stablvar( p -> symbol , p2type( p -> type ) , cbn
178 			    , p -> value[ NL_OFFS ] , lwidth( p -> type ) );
179 		    }
180 		}
181 	    }
182 	}
183 	stablbrac( cbn );
184 	    /*
185 	     *	register save mask
186 	     */
187 	putprintf( "	.word	" , 1 );
188         putprintf( PREFIXFORMAT , 0 , LABELPREFIX , savlabel );
189 	putjbr( botlabel );
190 	putlab( toplabel );
191 	if ( profflag ) {
192 		/*
193 		 *	call mcount for profiling
194 		 */
195 	    putprintf( "	moval	" , 1 );
196 	    putprintf( PREFIXFORMAT , 1 , LABELPREFIX , proflabel );
197 	    putprintf( ",r0" , 0 );
198 	    putprintf( "	jsb	mcount" , 0 );
199 	    putprintf( "	.data" , 0 );
200 	    putprintf( "	.align	2" , 0 );
201 	    putlab( proflabel );
202 	    putprintf( "	.long	0" , 0 );
203 	    putprintf( "	.text" , 0 );
204 	}
205 	    /*
206 	     *	set up unwind exception vector.
207 	     */
208 	putprintf( "	moval	%s,%d(%s)" , 0
209 		, UNWINDNAME , UNWINDOFFSET , P2FPNAME );
210 	    /*
211 	     *	save address of display entry, for unwind.
212 	     */
213 	putprintf( "	moval	%s+%d,%d(%s)" , 0
214 		, DISPLAYNAME , cbn * sizeof(struct dispsave)
215 		, DPTROFFSET , P2FPNAME );
216 	    /*
217 	     *	save old display
218 	     */
219 	putprintf( "	movq	%s+%d,%d(%s)" , 0
220 		, DISPLAYNAME , cbn * sizeof(struct dispsave)
221 		, DSAVEOFFSET , P2FPNAME );
222 	    /*
223 	     *	set up new display by saving AP and FP in appropriate
224 	     *	slot in display structure.
225 	     */
226 	putprintf( "	movq	%s,%s+%d" , 0
227 		, P2APNAME , DISPLAYNAME , cbn * sizeof(struct dispsave) );
228 	    /*
229 	     *	set underflow checking if runtime tests
230 	     */
231 	if ( opt( 't' ) ) {
232 	    putprintf( "	bispsw	$0xe0" , 0 );
233 	}
234 	    /*
235 	     *	ask second pass to allocate known locals
236 	     */
237 	putlbracket( ftnno , -sizes[ cbn ].om_max );
238 	    /*
239 	     *	and zero them if checking is on
240 	     *	by calling blkclr( bytes of locals , starting local address );
241 	     */
242 	if ( opt( 't' ) && ( -sizes[ cbn ].om_max ) > DPOFF1 ) {
243 	    putleaf( P2ICON , 0 , 0 , ADDTYPE( P2FTN | P2INT , P2PTR )
244 		    , "_blkclr" );
245 	    putleaf( P2ICON ,  ( -sizes[ cbn ].om_max ) - DPOFF1
246 		    , 0 , P2INT , 0 );
247 	    putLV( 0 , cbn , sizes[ cbn ].om_max , NLOCAL , P2CHAR );
248 	    putop( P2LISTOP , P2INT );
249 	    putop( P2CALL , P2INT );
250 	    putdot( filename , line );
251 	}
252 #endif PC
253 	if ( monflg ) {
254 		if ( fp -> value[ NL_CNTR ] != 0 ) {
255 			inccnt( fp -> value [ NL_CNTR ] );
256 		}
257 		inccnt( bodycnts[ fp -> nl_block & 037 ] );
258 	}
259 	if (fp->class == PROG) {
260 		/*
261 		 * The glorious buffers option.
262 		 *          0 = don't buffer output
263 		 *          1 = line buffer output
264 		 *          2 = 512 byte buffer output
265 		 */
266 #		ifdef OBJ
267 		    if (opt('b') != 1)
268 			    put(1, O_BUFF | opt('b') << 8);
269 #		endif OBJ
270 #		ifdef PC
271 		    if ( opt( 'b' ) != 1 ) {
272 			putleaf( P2ICON , 0 , 0
273 				, ADDTYPE( P2FTN | P2INT , P2PTR ) , "_BUFF" );
274 			putleaf( P2ICON , opt( 'b' ) , 0 , P2INT , 0 );
275 			putop( P2CALL , P2INT );
276 			putdot( filename , line );
277 		    }
278 #		endif PC
279 		out = 0;
280 		for (p = fp->chain; p != NIL; p = p->chain) {
281 			if (strcmp(p->symbol, "input") == 0) {
282 				inp++;
283 				continue;
284 			}
285 			if (strcmp(p->symbol, "output") == 0) {
286 				out++;
287 				continue;
288 			}
289 			iop = lookup1(p->symbol);
290 			if (iop == NIL || bn != cbn) {
291 				error("File %s listed in program statement but not declared", p->symbol);
292 				continue;
293 			}
294 			if (iop->class != VAR) {
295 				error("File %s listed in program statement but declared as a %s", p->symbol, classes[iop->class]);
296 				continue;
297 			}
298 			if (iop->type == NIL)
299 				continue;
300 			if (iop->type->class != FILET) {
301 				error("File %s listed in program statement but defined as %s",
302 					p->symbol, nameof(iop->type));
303 				continue;
304 			}
305 #			ifdef OBJ
306 			    put(2, O_CON24, text(iop->type) ? 0 : width(iop->type->type));
307 			    i = lenstr(p->symbol,0);
308 			    put(2, O_CON24, i);
309 			    put(2, O_LVCON, i);
310 			    putstr(p->symbol, 0);
311 			    put(2, O_LV | bn<<8+INDX, (int)iop->value[NL_OFFS]);
312 			    put(1, O_DEFNAME);
313 #			endif OBJ
314 #			ifdef PC
315 			    putleaf( P2ICON , 0 , 0
316 				    , ADDTYPE( P2FTN | P2INT , P2PTR )
317 				    , "_DEFNAME" );
318 			    putLV( p -> symbol , bn , iop -> value[NL_OFFS] ,
319 				    iop -> extra_flags , p2type( iop ) );
320 			    putCONG( p -> symbol , strlen( p -> symbol )
321 				    , LREQ );
322 			    putop( P2LISTOP , P2INT );
323 			    putleaf( P2ICON , strlen( p -> symbol )
324 				    , 0 , P2INT , 0 );
325 			    putop( P2LISTOP , P2INT );
326 			    putleaf( P2ICON
327 				, text(iop->type) ? 0 : width(iop->type->type)
328 				, 0 , P2INT , 0 );
329 			    putop( P2LISTOP , P2INT );
330 			    putop( P2CALL , P2INT );
331 			    putdot( filename , line );
332 #			endif PC
333 		}
334 		if (out == 0 && fp->chain != NIL) {
335 			recovered();
336 			error("The file output must appear in the program statement file list");
337 		}
338 	}
339 	/*
340 	 * Process the prog/proc/func body
341 	 */
342 	noreach = 0;
343 	line = bundle[1];
344 	statlist(blk);
345 #	ifdef PTREE
346 	    {
347 		pPointer Body = tCopy( blk );
348 
349 		pDEF( PorFHeader[ nesting -- ] ).PorFBody = Body;
350 	    }
351 #	endif PTREE
352 #	ifdef OBJ
353 	    if (cbn== 1 && monflg != 0) {
354 		    patchfil(cntpatch - 2, (long)cnts, 2);
355 		    patchfil(nfppatch - 2, (long)pfcnt, 2);
356 	    }
357 #	endif OBJ
358 #	ifdef PC
359 	    if ( fp -> class == PROG && monflg ) {
360 		putleaf( P2ICON , 0 , 0 , ADDTYPE( P2FTN | P2INT , P2PTR )
361 			, "_PMFLUSH" );
362 		putleaf( P2ICON , cnts , 0 , P2INT , 0 );
363 		putleaf( P2ICON , pfcnt , 0 , P2INT , 0 );
364 		putop( P2LISTOP , P2INT );
365 		putLV( PCPCOUNT , 0 , 0 , NGLOBAL , P2INT );
366 		putop( P2LISTOP , P2INT );
367 		putop( P2CALL , P2INT );
368 		putdot( filename , line );
369 	    }
370 #	endif PC
371 	if (fp->class == PROG && inp == 0 && (input->nl_flags & (NUSED|NMOD)) != 0) {
372 		recovered();
373 		error("Input is used but not defined in the program statement");
374 	}
375 	/*
376 	 * Clean up the symbol table displays and check for unresolves
377 	 */
378 	line = endline;
379 	b = cbn;
380 	Fp = fp;
381 	chkref = syneflg == errcnt[cbn] && opt('w') == 0;
382 	for (i = 0; i <= 077; i++) {
383 		for (p = disptab[i]; p != NIL && (p->nl_block & 037) == b; p = p->nl_next) {
384 			/*
385 			 * Check for variables defined
386 			 * but not referenced
387 			 */
388 			if (chkref && p->symbol != NIL)
389 			switch (p->class) {
390 				case FIELD:
391 					/*
392 					 * If the corresponding record is
393 					 * unused, we shouldn't complain about
394 					 * the fields.
395 					 */
396 				default:
397 					if ((p->nl_flags & (NUSED|NMOD)) == 0) {
398 						warning();
399 						nerror("%s %s is neither used nor set", classes[p->class], p->symbol);
400 						break;
401 					}
402 					/*
403 					 * If a var parameter is either
404 					 * modified or used that is enough.
405 					 */
406 					if (p->class == REF)
407 						continue;
408 #					ifdef OBJ
409 					    if ((p->nl_flags & NUSED) == 0) {
410 						warning();
411 						nerror("%s %s is never used", classes[p->class], p->symbol);
412 						break;
413 					    }
414 #					endif OBJ
415 #					ifdef PC
416 					    if (((p->nl_flags & NUSED) == 0) && ((p->extra_flags & NEXTERN) == 0)) {
417 						warning();
418 						nerror("%s %s is never used", classes[p->class], p->symbol);
419 						break;
420 					    }
421 #					endif PC
422 					if ((p->nl_flags & NMOD) == 0) {
423 						warning();
424 						nerror("%s %s is used but never set", classes[p->class], p->symbol);
425 						break;
426 					}
427 				case LABEL:
428 				case FVAR:
429 				case BADUSE:
430 					break;
431 			}
432 			switch (p->class) {
433 				case BADUSE:
434 					cp = "s";
435 					if (p->chain->ud_next == NIL)
436 						cp++;
437 					eholdnl();
438 					if (p->value[NL_KINDS] & ISUNDEF)
439 						nerror("%s undefined on line%s", p->symbol, cp);
440 					else
441 						nerror("%s improperly used on line%s", p->symbol, cp);
442 					pnumcnt = 10;
443 					pnums(p->chain);
444 					pchr('\n');
445 					break;
446 
447 				case FUNC:
448 				case PROC:
449 #					ifdef OBJ
450 					    if ((p->nl_flags & NFORWD))
451 						nerror("Unresolved forward declaration of %s %s", classes[p->class], p->symbol);
452 #					endif OBJ
453 #					ifdef PC
454 					    if ((p->nl_flags & NFORWD) && ((p->extra_flags & NEXTERN) == 0))
455 						nerror("Unresolved forward declaration of %s %s", classes[p->class], p->symbol);
456 #					endif PC
457 					break;
458 
459 				case LABEL:
460 					if (p->nl_flags & NFORWD)
461 						nerror("label %s was declared but not defined", p->symbol);
462 					break;
463 				case FVAR:
464 					if ((p->nl_flags & NMOD) == 0)
465 						nerror("No assignment to the function variable");
466 					break;
467 			}
468 		}
469 		/*
470 		 * Pop this symbol
471 		 * table slot
472 		 */
473 		disptab[i] = p;
474 	}
475 
476 #	ifdef OBJ
477 	    put(1, O_END);
478 #	endif OBJ
479 #	ifdef PC
480 		/*
481 		 *	if there were file variables declared at this level
482 		 *	call pclose( &__disply[ cbn ] ) to clean them up.
483 		 */
484 	    if ( dfiles[ cbn ] ) {
485 		putleaf( P2ICON , 0 , 0 , ADDTYPE( P2FTN | P2INT , P2PTR )
486 			, "_PCLOSE" );
487 		putRV( DISPLAYNAME , 0 , cbn * sizeof( struct dispsave ) ,
488 			NGLOBAL , P2PTR | P2CHAR );
489 		putop( P2CALL , P2INT );
490 		putdot( filename , line );
491 	    }
492 		/*
493 		 *	if this is a function,
494 		 *	the function variable is the return value.
495 		 *	if it's a scalar valued function, return scalar,
496 		 *	else, return a pointer to the structure value.
497 		 */
498 	    if ( fp -> class == FUNC ) {
499 		struct nl	*fvar = fp -> ptr[ NL_FVAR ];
500 		long		fvartype = p2type( fvar -> type );
501 		long		label;
502 		char		labelname[ BUFSIZ ];
503 
504 		switch ( classify( fvar -> type ) ) {
505 		    case TBOOL:
506 		    case TCHAR:
507 		    case TINT:
508 		    case TSCAL:
509 		    case TDOUBLE:
510 		    case TPTR:
511 			putRV( fvar -> symbol , ( fvar -> nl_block ) & 037 ,
512 				fvar -> value[ NL_OFFS ] ,
513 				fvar -> extra_flags ,
514 				fvartype );
515 			break;
516 		    default:
517 			label = getlab();
518 			sprintf( labelname , PREFIXFORMAT ,
519 				LABELPREFIX , label );
520 			putprintf( "	.data" , 0 );
521 			putprintf( "	.lcomm	%s,%d" , 0 ,
522 				    labelname , lwidth( fvar -> type ) );
523 			putprintf( "	.text" , 0 );
524 			putleaf( P2NAME , 0 , 0 , fvartype , labelname );
525 			putLV( fvar -> symbol , ( fvar -> nl_block ) & 037 ,
526 				fvar -> value[ NL_OFFS ] ,
527 				fvar -> extra_flags ,
528 				fvartype );
529 			putstrop( P2STASG , fvartype , lwidth( fvar -> type ) ,
530 				align( fvar -> type ) );
531 			putdot( filename , line );
532 			putleaf( P2ICON , 0 , 0 , fvartype , labelname );
533 			break;
534 		}
535 		putop( P2FORCE , fvartype );
536 		putdot( filename , line );
537 	    }
538 		/*
539 		 *	restore old display entry from save area
540 		 */
541 
542 	    putprintf( "	movq	%d(%s),%s+%d" , 0
543 		, DSAVEOFFSET , P2FPNAME
544 		, DISPLAYNAME , cbn * sizeof(struct dispsave) );
545 	    stabrbrac( cbn );
546 	    putprintf( "	ret" , 0 );
547 		/*
548 		 *	let the second pass allocate locals
549 		 * 	and registers
550 		 */
551 	    putprintf( "	.set	" , 1 );
552 	    putprintf( PREFIXFORMAT , 1 , LABELPREFIX , savlabel );
553 	    putprintf( ", 0x%x" , 0 , savmask() );
554 	    putlab( botlabel );
555 	    putprintf( "	subl2	$LF%d,sp" , 0 , ftnno );
556 	    putrbracket( ftnno );
557 	    putjbr( toplabel );
558 		/*
559 		 *  put down the entry point for formal calls
560 		 *  the arguments for FCALL have been passed to us
561 		 *  as hidden parameters after the regular arguments.
562 		 */
563 	    if ( fp -> class != PROG ) {
564 		putprintf( "%s%s:" , 0 , FORMALPREFIX , extname );
565 		putprintf( "	.word	" , 1 );
566 		putprintf( PREFIXFORMAT , 0 , LABELPREFIX , savlabel );
567 		putleaf( P2ICON , 0 , 0 , ADDTYPE( P2FTN | P2INT , P2PTR ) ,
568 			"_FCALL" );
569 		putRV( 0 , cbn ,
570 		    fp -> value[ NL_OFFS ] + sizeof( struct formalrtn * ) ,
571 		    NPARAM ,
572 		    P2PTR | P2STRTY );
573 		putRV( 0 , cbn , fp -> value[ NL_OFFS ] ,
574 			NPARAM , P2PTR|P2STRTY );
575 		putop( P2LISTOP , P2INT );
576 		putop( P2CALL , P2INT );
577 		putdot( filename , line );
578 		putjbr( botlabel );
579 	    }
580 		/*
581 		 *	declare pcp counters, if any
582 		 */
583 	    if ( monflg && fp -> class == PROG ) {
584 		putprintf( "	.data" , 0 );
585 		putprintf( "	.comm	" , 1 );
586 		putprintf( PCPCOUNT , 1 );
587 		putprintf( ",%d" , 0 , ( cnts + 1 ) * sizeof (long) );
588 		putprintf( "	.text" , 0 );
589 	    }
590 #	endif PC
591 #ifdef DEBUG
592 	dumpnl(fp->ptr[2], fp->symbol);
593 #endif
594 
595 #ifdef OBJ
596 	/*
597 	 * save the namelist for the debugger pdx
598 	 */
599 
600 	savenl(fp->ptr[2], fp->symbol);
601 #endif
602 
603 	/*
604 	 * Restore the
605 	 * (virtual) name list
606 	 * position
607 	 */
608 	nlfree(fp->ptr[2]);
609 	/*
610 	 * Proc/func has been
611 	 * resolved
612 	 */
613 	fp->nl_flags &= ~NFORWD;
614 	/*
615 	 * Patch the beg
616 	 * of the proc/func to
617 	 * the proper variable size
618 	 */
619 	if (Fp == NIL)
620 		elineon();
621 #	ifdef OBJ
622 	    patchfil(var, (long)(-sizes[cbn].om_max), 2);
623 #	endif OBJ
624 	cbn--;
625 	if (inpflist(fp->symbol)) {
626 		opop('l');
627 	}
628 }
629 
630 #ifdef PC
631     /*
632      *	construct the long name of a function based on it's static nesting.
633      *	into a caller-supplied buffer (that should be about BUFSIZ big).
634      */
635 sextname( buffer , name , level )
636     char	buffer[];
637     char	*name;
638     int		level;
639 {
640     char	*starthere;
641     int	i;
642 
643     starthere = &buffer[0];
644     for ( i = 1 ; i < level ; i++ ) {
645 	sprintf( starthere , EXTFORMAT , enclosing[ i ] );
646 	starthere += strlen( enclosing[ i ] ) + 1;
647     }
648     sprintf( starthere , EXTFORMAT , name );
649     starthere += strlen( name ) + 1;
650     if ( starthere >= &buffer[ BUFSIZ ] ) {
651 	panic( "sextname" );
652     }
653 }
654 #endif PC
655