xref: /freebsd/usr.bin/m4/main.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*	$OpenBSD: main.c,v 1.53 2002/04/26 16:15:16 espie Exp $	*/
2 /*	$NetBSD: main.c,v 1.12 1997/02/08 23:54:49 cgd Exp $	*/
3 
4 /*-
5  * Copyright (c) 1989, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Ozan Yigit at York University.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1989, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)main.c	8.1 (Berkeley) 6/6/93";
45 #else
46 #if 0
47 static char rcsid[] = "$OpenBSD: main.c,v 1.53 2002/04/26 16:15:16 espie Exp $";
48 #endif
49 #endif
50 #endif /* not lint */
51 
52 #include <sys/cdefs.h>
53 __FBSDID("$FreeBSD$");
54 
55 /*
56  * main.c
57  * Facility: m4 macro processor
58  * by: oz
59  */
60 
61 #include <sys/types.h>
62 #include <assert.h>
63 #include <signal.h>
64 #include <errno.h>
65 #include <unistd.h>
66 #include <stdio.h>
67 #include <ctype.h>
68 #include <string.h>
69 #include <stddef.h>
70 #include <stdlib.h>
71 #include <err.h>
72 #include <locale.h>
73 #include "mdef.h"
74 #include "stdd.h"
75 #include "extern.h"
76 #include "pathnames.h"
77 
78 ndptr hashtab[HASHSIZE];	/* hash table for macros etc.  */
79 stae *mstack;		 	/* stack of m4 machine         */
80 char *sstack;		 	/* shadow stack, for string space extension */
81 static size_t STACKMAX;		/* current maximum size of stack */
82 int sp; 			/* current m4  stack pointer   */
83 int fp; 			/* m4 call frame pointer       */
84 struct input_file infile[MAXINP];/* input file stack (0=stdin)  */
85 char *inname[MAXINP];		/* names of these input files */
86 int inlineno[MAXINP];		/* current number in each input file */
87 FILE **outfile;			/* diversion array(0=bitbucket)*/
88 int maxout;
89 FILE *active;			/* active output file pointer  */
90 int ilevel = 0; 		/* input file stack pointer    */
91 int oindex = 0; 		/* diversion index..	       */
92 char null[] = "";		/* as it says.. just a null..  */
93 const char *m4wraps = "";       /* m4wrap string default..     */
94 char lquote[MAXCCHARS+1] = {LQUOTE};	/* left quote character  (`)   */
95 char rquote[MAXCCHARS+1] = {RQUOTE};	/* right quote character (')   */
96 char scommt[MAXCCHARS+1] = {SCOMMT};	/* start character for comment */
97 char ecommt[MAXCCHARS+1] = {ECOMMT};	/* end character for comment   */
98 int synccpp;			/* Line synchronisation for C preprocessor */
99 
100 struct keyblk keywrds[] = {	/* m4 keywords to be installed */
101 	{ "include",      INCLTYPE },
102 	{ "sinclude",     SINCTYPE },
103 	{ "define",       DEFITYPE },
104 	{ "defn",         DEFNTYPE },
105 	{ "divert",       DIVRTYPE | NOARGS },
106 	{ "expr",         EXPRTYPE },
107 	{ "eval",         EXPRTYPE },
108 	{ "substr",       SUBSTYPE },
109 	{ "ifelse",       IFELTYPE },
110 	{ "ifdef",        IFDFTYPE },
111 	{ "len",          LENGTYPE },
112 	{ "incr",         INCRTYPE },
113 	{ "decr",         DECRTYPE },
114 	{ "dnl",          DNLNTYPE | NOARGS },
115 	{ "changequote",  CHNQTYPE | NOARGS },
116 	{ "changecom",    CHNCTYPE | NOARGS },
117 	{ "index",        INDXTYPE },
118 #ifdef EXTENDED
119 	{ "paste",        PASTTYPE },
120 	{ "spaste",       SPASTYPE },
121     	/* Newer extensions, needed to handle gnu-m4 scripts */
122 	{ "indir",        INDIRTYPE},
123 	{ "builtin",      BUILTINTYPE},
124 	{ "patsubst",	  PATSTYPE},
125 	{ "regexp",	  REGEXPTYPE},
126 	{ "esyscmd",	  ESYSCMDTYPE},
127 	{ "__file__",	  FILENAMETYPE | NOARGS},
128 	{ "__line__",	  LINETYPE | NOARGS},
129 #endif
130 	{ "popdef",       POPDTYPE },
131 	{ "pushdef",      PUSDTYPE },
132 	{ "dumpdef",      DUMPTYPE | NOARGS },
133 	{ "shift",        SHIFTYPE | NOARGS },
134 	{ "translit",     TRNLTYPE },
135 	{ "undefine",     UNDFTYPE },
136 	{ "undivert",     UNDVTYPE | NOARGS },
137 	{ "divnum",       DIVNTYPE | NOARGS },
138 	{ "maketemp",     MKTMTYPE },
139 	{ "errprint",     ERRPTYPE | NOARGS },
140 	{ "m4wrap",       M4WRTYPE | NOARGS },
141 	{ "m4exit",       EXITTYPE | NOARGS },
142 	{ "syscmd",       SYSCTYPE },
143 	{ "sysval",       SYSVTYPE | NOARGS },
144 	{ "traceon",	  TRACEONTYPE | NOARGS },
145 	{ "traceoff",	  TRACEOFFTYPE | NOARGS },
146 
147 #if defined(unix) || defined(__unix__)
148 	{ "unix",         SELFTYPE | NOARGS },
149 #else
150 #ifdef vms
151 	{ "vms",          SELFTYPE | NOARGS },
152 #endif
153 #endif
154 };
155 
156 #define MAXKEYS	(sizeof(keywrds)/sizeof(struct keyblk))
157 
158 #define MAXRECORD 50
159 static struct position {
160 	char *name;
161 	unsigned long line;
162 } quotes[MAXRECORD], paren[MAXRECORD];
163 
164 static void record(struct position *, int);
165 static void dump_stack(struct position *, int);
166 
167 static void macro(void);
168 static void initkwds(void);
169 static ndptr inspect(int, char *);
170 static int do_look_ahead(int, const char *);
171 
172 static void enlarge_stack(void);
173 
174 int
175 main(int argc, char *argv[])
176 {
177 	int c;
178 	int n;
179 	int rval;
180 	char *p;
181 
182 	setlocale(LC_ALL, "");
183 
184 	traceout = stderr;
185 
186 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
187 		signal(SIGINT, onintr);
188 
189 	initkwds();
190 	initspaces();
191 	STACKMAX = INITSTACKMAX;
192 
193 	mstack = (stae *)xalloc(sizeof(stae) * STACKMAX);
194 	sstack = (char *)xalloc(STACKMAX);
195 
196 	maxout = 0;
197 	outfile = NULL;
198 	resizedivs(MAXOUT);
199 
200 	while ((c = getopt(argc, argv, "gst:d:D:U:o:I:")) != -1)
201 		switch(c) {
202 		case 'D':               /* define something..*/
203 			for (p = optarg; *p; p++)
204 				if (*p == '=')
205 					break;
206 			if (p == optarg)
207 				errx(1, "null variable cannot be defined");
208 			if (*p)
209 				*p++ = EOS;
210 			dodefine(optarg, p);
211 			break;
212 		case 'I':
213 			addtoincludepath(optarg);
214 			break;
215 		case 'U':               /* undefine...       */
216 			remhash(optarg, TOP);
217 			break;
218 		case 'g':
219 			mimic_gnu = 1;
220 			break;
221 		case 'd':
222 			set_trace_flags(optarg);
223 			break;
224 		case 's':
225 			synccpp = 1;
226 			break;
227 		case 't':
228 			mark_traced(optarg, 1);
229 			break;
230 		case 'o':
231 			trace_file(optarg);
232                         break;
233 		case '?':
234 		default:
235 			usage();
236 		}
237 
238         argc -= optind;
239         argv += optind;
240 
241 	rval = 0;
242 	active = stdout;		/* default active output     */
243 	bbase[0] = bufbase;
244         if (!argc) {
245  		sp = -1;		/* stack pointer initialized */
246 		fp = 0; 		/* frame pointer initialized */
247 		set_input(infile+0, stdin, "stdin");
248 					/* default input (naturally) */
249 		if ((inname[0] = strdup("-")) == NULL)
250 			err(1, NULL);
251 		inlineno[0] = 1;
252 		emitline();
253 		macro();
254 	} else
255 		for (; argc--; ++argv) {
256 			p = *argv;
257 			if (p[0] == '-' && p[1] == EOS)
258 				set_input(infile, stdin, "stdin");
259 			else if (fopen_trypath(infile, p) == NULL) {
260 				warn("%s", p);
261 				rval = 1;
262 				continue;
263 			}
264 			sp = -1;
265 			fp = 0;
266 			if ((inname[0] = strdup(p)) == NULL)
267 				err(1, NULL);
268 			inlineno[0] = 1;
269 			emitline();
270 			macro();
271 		    	release_input(infile);
272 		}
273 
274 	if (*m4wraps) { 		/* anything for rundown ??   */
275 		ilevel = 0;		/* in case m4wrap includes.. */
276 		bufbase = bp = buf;	/* use the entire buffer   */
277 		pbstr(m4wraps); 	/* user-defined wrapup act   */
278 		macro();		/* last will and testament   */
279 	}
280 
281 	if (active != stdout)
282 		active = stdout;	/* reset output just in case */
283 	for (n = 1; n < maxout; n++)	/* default wrap-up: undivert */
284 		if (outfile[n] != NULL)
285 			getdiv(n);
286 					/* remove bitbucket if used  */
287 	if (outfile[0] != NULL) {
288 		(void) fclose(outfile[0]);
289 	}
290 
291 	exit(rval);
292 }
293 
294 /*
295  * Look ahead for `token'.
296  * (on input `t == token[0]')
297  * Used for comment and quoting delimiters.
298  * Returns 1 if `token' present; copied to output.
299  *         0 if `token' not found; all characters pushed back
300  */
301 static int
302 do_look_ahead(int t, const char *token)
303 {
304 	int i;
305 
306 	assert((unsigned char)t == (unsigned char)token[0]);
307 
308 	for (i = 1; *++token; i++) {
309 		t = gpbc();
310 		if (t == EOF || (unsigned char)t != (unsigned char)*token) {
311 			putback(t);
312 			while (--i)
313 				putback(*--token);
314 			return 0;
315 		}
316 	}
317 	return 1;
318 }
319 
320 #define LOOK_AHEAD(t, token) (t != EOF && 		\
321     (unsigned char)(t)==(unsigned char)(token)[0] && 	\
322     do_look_ahead(t,token))
323 
324 /*
325  * macro - the work horse..
326  */
327 static void
328 macro(void)
329 {
330 	char token[MAXTOK+1];
331 	int t, l;
332 	ndptr p;
333 	int  nlpar;
334 
335 	cycle {
336 		t = gpbc();
337 		if (t == '_' || isalpha(t)) {
338 			p = inspect(t, token);
339 			if (p != nil)
340 				putback(l = gpbc());
341 			if (p == nil || (l != LPAREN &&
342 			    (p->type & NEEDARGS) != 0))
343 				outputstr(token);
344 			else {
345 		/*
346 		 * real thing.. First build a call frame:
347 		 */
348 				pushf(fp);	/* previous call frm */
349 				pushf(p->type); /* type of the call  */
350 				pushf(0);	/* parenthesis level */
351 				fp = sp;	/* new frame pointer */
352 		/*
353 		 * now push the string arguments:
354 		 */
355 				pushs1(p->defn);	/* defn string */
356 				pushs1(p->name);	/* macro name  */
357 				pushs(ep);	      	/* start next..*/
358 
359 				if (l != LPAREN && PARLEV == 0)  {
360 				    /* no bracks  */
361 					chrsave(EOS);
362 
363 					if ((uintptr_t)sp == STACKMAX)
364 						errx(1, "internal stack overflow");
365 					eval((const char **) mstack+fp+1, 2,
366 					    CALTYP);
367 
368 					ep = PREVEP;	/* flush strspace */
369 					sp = PREVSP;	/* previous sp..  */
370 					fp = PREVFP;	/* rewind stack...*/
371 				}
372 			}
373 		} else if (t == EOF) {
374 			if (sp > -1) {
375 				warnx( "unexpected end of input, unclosed parenthesis:");
376 				dump_stack(paren, PARLEV);
377 				exit(1);
378 			}
379 			if (ilevel <= 0)
380 				break;			/* all done thanks.. */
381 			release_input(infile+ilevel--);
382 			free(inname[ilevel+1]);
383 			bufbase = bbase[ilevel];
384 			emitline();
385 			continue;
386 		}
387 	/*
388 	 * non-alpha token possibly seen..
389 	 * [the order of else if .. stmts is important.]
390 	 */
391 		else if (LOOK_AHEAD(t,lquote)) {	/* strip quotes */
392 			nlpar = 0;
393 			record(quotes, nlpar++);
394 			/*
395 			 * Opening quote: scan forward until matching
396 			 * closing quote has been found.
397 			 */
398 			do {
399 
400 				l = gpbc();
401 				if (LOOK_AHEAD(l,rquote)) {
402 					if (--nlpar > 0)
403 						outputstr(rquote);
404 				} else if (LOOK_AHEAD(l,lquote)) {
405 					record(quotes, nlpar++);
406 					outputstr(lquote);
407 				} else if (l == EOF) {
408 					if (nlpar == 1)
409 						warnx("unclosed quote:");
410 					else
411 						warnx("%d unclosed quotes:", nlpar);
412 					dump_stack(quotes, nlpar);
413 					exit(1);
414 				} else {
415 					if (nlpar > 0) {
416 						if (sp < 0)
417 							putc(l, active);
418 						else
419 							CHRSAVE(l);
420 					}
421 				}
422 			}
423 			while (nlpar != 0);
424 		}
425 
426 		else if (sp < 0 && LOOK_AHEAD(t, scommt)) {
427 			fputs(scommt, active);
428 
429 			for(;;) {
430 				t = gpbc();
431 				if (LOOK_AHEAD(t, ecommt)) {
432 					fputs(ecommt, active);
433 					break;
434 				}
435 				if (t == EOF)
436 					break;
437 				putc(t, active);
438 			}
439 		}
440 
441 		else if (sp < 0) {		/* not in a macro at all */
442 			putc(t, active);	/* output directly..	 */
443 		}
444 
445 		else switch(t) {
446 
447 		case LPAREN:
448 			if (PARLEV > 0)
449 				chrsave(t);
450 			while (isspace(l = gpbc()))
451 				;		/* skip blank, tab, nl.. */
452 			putback(l);
453 			record(paren, PARLEV++);
454 			break;
455 
456 		case RPAREN:
457 			if (--PARLEV > 0)
458 				chrsave(t);
459 			else {			/* end of argument list */
460 				chrsave(EOS);
461 
462 				if ((uintptr_t)sp == STACKMAX)
463 					errx(1, "internal stack overflow");
464 
465 				eval((const char **) mstack+fp+1, sp-fp,
466 				    CALTYP);
467 
468 				ep = PREVEP;	/* flush strspace */
469 				sp = PREVSP;	/* previous sp..  */
470 				fp = PREVFP;	/* rewind stack...*/
471 			}
472 			break;
473 
474 		case COMMA:
475 			if (PARLEV == 1) {
476 				chrsave(EOS);		/* new argument   */
477 				while (isspace(l = gpbc()))
478 					;
479 				putback(l);
480 				pushs(ep);
481 			} else
482 				chrsave(t);
483 			break;
484 
485 		default:
486 			if (LOOK_AHEAD(t, scommt)) {
487 				char *pc;
488 				for (pc = scommt; *pc; pc++)
489 					chrsave(*pc);
490 				for(;;) {
491 					t = gpbc();
492 					if (LOOK_AHEAD(t, ecommt)) {
493 						for (pc = ecommt; *pc; pc++)
494 							chrsave(*pc);
495 						break;
496 					}
497 					if (t == EOF)
498 					    break;
499 					CHRSAVE(t);
500 				}
501 			} else
502 				CHRSAVE(t);		/* stack the char */
503 			break;
504 		}
505 	}
506 }
507 
508 /*
509  * output string directly, without pushing it for reparses.
510  */
511 void
512 outputstr(const char *s)
513 {
514 	if (sp < 0)
515 		while (*s)
516 			putc(*s++, active);
517 	else
518 		while (*s)
519 			CHRSAVE(*s++);
520 }
521 
522 /*
523  * build an input token..
524  * consider only those starting with _ or A-Za-z. This is a
525  * combo with lookup to speed things up.
526  */
527 static ndptr
528 inspect(int c, char *tp)
529 {
530 	char *name = tp;
531 	char *etp = tp+MAXTOK;
532 	ndptr p;
533 	unsigned int h;
534 
535 	h = *tp++ = c;
536 
537 	while ((isalnum(c = gpbc()) || c == '_') && tp < etp)
538 		h = (h << 5) + h + (*tp++ = c);
539 	if (c != EOF)
540 		PUTBACK(c);
541 	*tp = EOS;
542 	/* token is too long, it won't match anything, but it can still
543 	 * be output. */
544 	if (tp == ep) {
545 		outputstr(name);
546 		while (isalnum(c = gpbc()) || c == '_') {
547 			if (sp < 0)
548 				putc(c, active);
549 			else
550 				CHRSAVE(c);
551 		}
552 		*name = EOS;
553 		return nil;
554 	}
555 
556 	for (p = hashtab[h % HASHSIZE]; p != nil; p = p->nxtptr)
557 		if (h == p->hv && STREQ(name, p->name))
558 			break;
559 	return p;
560 }
561 
562 /*
563  * initkwds - initialise m4 keywords as fast as possible.
564  * This very similar to install, but without certain overheads,
565  * such as calling lookup. Malloc is not used for storing the
566  * keyword strings, since we simply use the static pointers
567  * within keywrds block.
568  */
569 static void
570 initkwds(void)
571 {
572 	size_t i;
573 	unsigned int h;
574 	ndptr p;
575 
576 	for (i = 0; i < MAXKEYS; i++) {
577 		h = hash(keywrds[i].knam);
578 		p = (ndptr) xalloc(sizeof(struct ndblock));
579 		p->nxtptr = hashtab[h % HASHSIZE];
580 		hashtab[h % HASHSIZE] = p;
581 		p->name = xstrdup(keywrds[i].knam);
582 		p->defn = null;
583 		p->hv = h;
584 		p->type = keywrds[i].ktyp & TYPEMASK;
585 		if ((keywrds[i].ktyp & NOARGS) == 0)
586 			p->type |= NEEDARGS;
587 	}
588 }
589 
590 /* Look up a builtin type, even if overridden by the user */
591 int
592 builtin_type(const char *key)
593 {
594 	int i;
595 
596 	for (i = 0; i != MAXKEYS; i++)
597 		if (STREQ(keywrds[i].knam, key))
598 			return keywrds[i].ktyp;
599 	return -1;
600 }
601 
602 const char *
603 builtin_realname(int n)
604 {
605 	int i;
606 
607 	for (i = 0; i != MAXKEYS; i++)
608 		if (((keywrds[i].ktyp ^ n) & TYPEMASK) == 0)
609 			return keywrds[i].knam;
610 	return NULL;
611 }
612 
613 static void
614 record(struct position *t, int lev)
615 {
616 	if (lev < MAXRECORD) {
617 		t[lev].name = CURRENT_NAME;
618 		t[lev].line = CURRENT_LINE;
619 	}
620 }
621 
622 static void
623 dump_stack(struct position *t, int lev)
624 {
625 	int i;
626 
627 	for (i = 0; i < lev; i++) {
628 		if (i == MAXRECORD) {
629 			fprintf(stderr, "   ...\n");
630 			break;
631 		}
632 		fprintf(stderr, "   %s at line %lu\n",
633 			t[i].name, t[i].line);
634 	}
635 }
636 
637 
638 static void
639 enlarge_stack(void)
640 {
641 	STACKMAX *= 2;
642 	mstack = realloc(mstack, sizeof(stae) * STACKMAX);
643 	sstack = realloc(sstack, STACKMAX);
644 	if (mstack == NULL || sstack == NULL)
645 		errx(1, "Evaluation stack overflow (%lu)",
646 		    (unsigned long)STACKMAX);
647 }
648 
649 /* Emit preprocessor #line directive if -s option used. */
650 void
651 emitline(void)
652 {
653 
654 	if (synccpp)
655 		fprintf(active, "#line %d \"%s\"\n", inlineno[ilevel],
656 			inname[ilevel]);
657 }
658