xref: /freebsd/usr.bin/m4/main.c (revision 71fe318b852b8dfb3e799cb12ef184750f7f8eac)
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  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  */
39 
40 #ifndef lint
41 static char copyright[] =
42 "@(#) Copyright (c) 1989, 1993\n\
43 	The Regents of the University of California.  All rights reserved.\n";
44 #endif /* not lint */
45 
46 #ifndef lint
47 #if 0
48 static char sccsid[] = "@(#)main.c	8.1 (Berkeley) 6/6/93";
49 #else
50 #if 0
51 static char rcsid[] = "$OpenBSD: main.c,v 1.53 2002/04/26 16:15:16 espie Exp $";
52 #endif
53 #endif
54 #endif /* not lint */
55 
56 #include <sys/cdefs.h>
57 __FBSDID("$FreeBSD$");
58 
59 /*
60  * main.c
61  * Facility: m4 macro processor
62  * by: oz
63  */
64 
65 #include <sys/types.h>
66 #include <assert.h>
67 #include <signal.h>
68 #include <errno.h>
69 #include <unistd.h>
70 #include <stdio.h>
71 #include <ctype.h>
72 #include <string.h>
73 #include <stddef.h>
74 #include <stdlib.h>
75 #include <err.h>
76 #include "mdef.h"
77 #include "stdd.h"
78 #include "extern.h"
79 #include "pathnames.h"
80 
81 ndptr hashtab[HASHSIZE];	/* hash table for macros etc.  */
82 stae *mstack;		 	/* stack of m4 machine         */
83 char *sstack;		 	/* shadow stack, for string space extension */
84 static size_t STACKMAX;		/* current maximum size of stack */
85 int sp; 			/* current m4  stack pointer   */
86 int fp; 			/* m4 call frame pointer       */
87 struct input_file infile[MAXINP];/* input file stack (0=stdin)  */
88 char *inname[MAXINP];		/* names of these input files */
89 int inlineno[MAXINP];		/* current number in each input file */
90 FILE **outfile;			/* diversion array(0=bitbucket)*/
91 int maxout;
92 FILE *active;			/* active output file pointer  */
93 int ilevel = 0; 		/* input file stack pointer    */
94 int oindex = 0; 		/* diversion index..	       */
95 const char *null = "";          /* as it says.. just a null..  */
96 const char *m4wraps = "";       /* m4wrap string default..     */
97 char lquote[MAXCCHARS+1] = {LQUOTE};	/* left quote character  (`)   */
98 char rquote[MAXCCHARS+1] = {RQUOTE};	/* right quote character (')   */
99 char scommt[MAXCCHARS+1] = {SCOMMT};	/* start character for comment */
100 char ecommt[MAXCCHARS+1] = {ECOMMT};	/* end character for comment   */
101 int synccpp;			/* Line synchronisation for C preprocessor */
102 
103 struct keyblk keywrds[] = {	/* m4 keywords to be installed */
104 	{ "include",      INCLTYPE },
105 	{ "sinclude",     SINCTYPE },
106 	{ "define",       DEFITYPE },
107 	{ "defn",         DEFNTYPE },
108 	{ "divert",       DIVRTYPE | NOARGS },
109 	{ "expr",         EXPRTYPE },
110 	{ "eval",         EXPRTYPE },
111 	{ "substr",       SUBSTYPE },
112 	{ "ifelse",       IFELTYPE },
113 	{ "ifdef",        IFDFTYPE },
114 	{ "len",          LENGTYPE },
115 	{ "incr",         INCRTYPE },
116 	{ "decr",         DECRTYPE },
117 	{ "dnl",          DNLNTYPE | NOARGS },
118 	{ "changequote",  CHNQTYPE | NOARGS },
119 	{ "changecom",    CHNCTYPE | NOARGS },
120 	{ "index",        INDXTYPE },
121 #ifdef EXTENDED
122 	{ "paste",        PASTTYPE },
123 	{ "spaste",       SPASTYPE },
124     	/* Newer extensions, needed to handle gnu-m4 scripts */
125 	{ "indir",        INDIRTYPE},
126 	{ "builtin",      BUILTINTYPE},
127 	{ "patsubst",	  PATSTYPE},
128 	{ "regexp",	  REGEXPTYPE},
129 	{ "esyscmd",	  ESYSCMDTYPE},
130 	{ "__file__",	  FILENAMETYPE | NOARGS},
131 	{ "__line__",	  LINETYPE | NOARGS},
132 #endif
133 	{ "popdef",       POPDTYPE },
134 	{ "pushdef",      PUSDTYPE },
135 	{ "dumpdef",      DUMPTYPE | NOARGS },
136 	{ "shift",        SHIFTYPE | NOARGS },
137 	{ "translit",     TRNLTYPE },
138 	{ "undefine",     UNDFTYPE },
139 	{ "undivert",     UNDVTYPE | NOARGS },
140 	{ "divnum",       DIVNTYPE | NOARGS },
141 	{ "maketemp",     MKTMTYPE },
142 	{ "errprint",     ERRPTYPE | NOARGS },
143 	{ "m4wrap",       M4WRTYPE | NOARGS },
144 	{ "m4exit",       EXITTYPE | NOARGS },
145 	{ "syscmd",       SYSCTYPE },
146 	{ "sysval",       SYSVTYPE | NOARGS },
147 	{ "traceon",	  TRACEONTYPE | NOARGS },
148 	{ "traceoff",	  TRACEOFFTYPE | NOARGS },
149 
150 #if defined(unix) || defined(__unix__)
151 	{ "unix",         SELFTYPE | NOARGS },
152 #else
153 #ifdef vms
154 	{ "vms",          SELFTYPE | NOARGS },
155 #endif
156 #endif
157 };
158 
159 #define MAXKEYS	(sizeof(keywrds)/sizeof(struct keyblk))
160 
161 #define MAXRECORD 50
162 static struct position {
163 	char *name;
164 	unsigned long line;
165 } quotes[MAXRECORD], paren[MAXRECORD];
166 
167 static void record(struct position *, int);
168 static void dump_stack(struct position *, int);
169 
170 static void macro(void);
171 static void initkwds(void);
172 static ndptr inspect(int, char *);
173 static int do_look_ahead(int, const char *);
174 
175 static void enlarge_stack(void);
176 
177 int
178 main(int argc, char *argv[])
179 {
180 	int c;
181 	int n;
182 	int rval;
183 	char *p;
184 
185 	traceout = stderr;
186 
187 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
188 		signal(SIGINT, onintr);
189 
190 	initkwds();
191 	initspaces();
192 	STACKMAX = INITSTACKMAX;
193 
194 	mstack = (stae *)xalloc(sizeof(stae) * STACKMAX);
195 	sstack = (char *)xalloc(STACKMAX);
196 
197 	maxout = 0;
198 	outfile = NULL;
199 	resizedivs(MAXOUT);
200 
201 	while ((c = getopt(argc, argv, "gst:d:D:U:o:I:")) != -1)
202 		switch(c) {
203 		case 'D':               /* define something..*/
204 			for (p = optarg; *p; p++)
205 				if (*p == '=')
206 					break;
207 			if (p == optarg)
208 				errx(1, "null variable cannot be defined");
209 			if (*p)
210 				*p++ = EOS;
211 			dodefine(optarg, p);
212 			break;
213 		case 'I':
214 			addtoincludepath(optarg);
215 			break;
216 		case 'U':               /* undefine...       */
217 			remhash(optarg, TOP);
218 			break;
219 		case 'g':
220 			mimic_gnu = 1;
221 			break;
222 		case 'd':
223 			set_trace_flags(optarg);
224 			break;
225 		case 's':
226 			synccpp = 1;
227 			break;
228 		case 't':
229 			mark_traced(optarg, 1);
230 			break;
231 		case 'o':
232 			trace_file(optarg);
233                         break;
234 		case '?':
235 		default:
236 			usage();
237 		}
238 
239         argc -= optind;
240         argv += optind;
241 
242 	rval = 0;
243 	active = stdout;		/* default active output     */
244 	bbase[0] = bufbase;
245         if (!argc) {
246  		sp = -1;		/* stack pointer initialized */
247 		fp = 0; 		/* frame pointer initialized */
248 		set_input(infile+0, stdin, "stdin");
249 					/* default input (naturally) */
250 		if ((inname[0] = strdup("-")) == NULL)
251 			err(1, NULL);
252 		inlineno[0] = 1;
253 		emitline();
254 		macro();
255 	} else
256 		for (; argc--; ++argv) {
257 			p = *argv;
258 			if (p[0] == '-' && p[1] == EOS)
259 				set_input(infile, stdin, "stdin");
260 			else if (fopen_trypath(infile, p) == NULL) {
261 				warn("%s", p);
262 				rval = 1;
263 				continue;
264 			}
265 			sp = -1;
266 			fp = 0;
267 			if ((inname[0] = strdup(p)) == NULL)
268 				err(1, NULL);
269 			inlineno[0] = 1;
270 			emitline();
271 			macro();
272 		    	release_input(infile);
273 		}
274 
275 	if (*m4wraps) { 		/* anything for rundown ??   */
276 		ilevel = 0;		/* in case m4wrap includes.. */
277 		bufbase = bp = buf;	/* use the entire buffer   */
278 		pbstr(m4wraps); 	/* user-defined wrapup act   */
279 		macro();		/* last will and testament   */
280 	}
281 
282 	if (active != stdout)
283 		active = stdout;	/* reset output just in case */
284 	for (n = 1; n < maxout; n++)	/* default wrap-up: undivert */
285 		if (outfile[n] != NULL)
286 			getdiv(n);
287 					/* remove bitbucket if used  */
288 	if (outfile[0] != NULL) {
289 		(void) fclose(outfile[0]);
290 	}
291 
292 	exit(rval);
293 }
294 
295 /*
296  * Look ahead for `token'.
297  * (on input `t == token[0]')
298  * Used for comment and quoting delimiters.
299  * Returns 1 if `token' present; copied to output.
300  *         0 if `token' not found; all characters pushed back
301  */
302 static int
303 do_look_ahead(int t, const char *token)
304 {
305 	int i;
306 
307 	assert((unsigned char)t == (unsigned char)token[0]);
308 
309 	for (i = 1; *++token; i++) {
310 		t = gpbc();
311 		if (t == EOF || (unsigned char)t != (unsigned char)*token) {
312 			putback(t);
313 			while (--i)
314 				putback(*--token);
315 			return 0;
316 		}
317 	}
318 	return 1;
319 }
320 
321 #define LOOK_AHEAD(t, token) (t != EOF && 		\
322     (unsigned char)(t)==(unsigned char)(token)[0] && 	\
323     do_look_ahead(t,token))
324 
325 /*
326  * macro - the work horse..
327  */
328 static void
329 macro(void)
330 {
331 	char token[MAXTOK+1];
332 	int t, l;
333 	ndptr p;
334 	int  nlpar;
335 
336 	cycle {
337 		t = gpbc();
338 		if (t == '_' || isalpha(t)) {
339 			p = inspect(t, token);
340 			if (p != nil)
341 				putback(l = gpbc());
342 			if (p == nil || (l != LPAREN &&
343 			    (p->type & NEEDARGS) != 0))
344 				outputstr(token);
345 			else {
346 		/*
347 		 * real thing.. First build a call frame:
348 		 */
349 				pushf(fp);	/* previous call frm */
350 				pushf(p->type); /* type of the call  */
351 				pushf(0);	/* parenthesis level */
352 				fp = sp;	/* new frame pointer */
353 		/*
354 		 * now push the string arguments:
355 		 */
356 				pushs1(p->defn);	/* defn string */
357 				pushs1(p->name);	/* macro name  */
358 				pushs(ep);	      	/* start next..*/
359 
360 				if (l != LPAREN && PARLEV == 0)  {
361 				    /* no bracks  */
362 					chrsave(EOS);
363 
364 					if ((uintptr_t)sp == STACKMAX)
365 						errx(1, "internal stack overflow");
366 					eval((const char **) mstack+fp+1, 2,
367 					    CALTYP);
368 
369 					ep = PREVEP;	/* flush strspace */
370 					sp = PREVSP;	/* previous sp..  */
371 					fp = PREVFP;	/* rewind stack...*/
372 				}
373 			}
374 		} else if (t == EOF) {
375 			if (sp > -1) {
376 				warnx( "unexpected end of input, unclosed parenthesis:");
377 				dump_stack(paren, PARLEV);
378 				exit(1);
379 			}
380 			if (ilevel <= 0)
381 				break;			/* all done thanks.. */
382 			release_input(infile+ilevel--);
383 			free(inname[ilevel+1]);
384 			bufbase = bbase[ilevel];
385 			emitline();
386 			continue;
387 		}
388 	/*
389 	 * non-alpha token possibly seen..
390 	 * [the order of else if .. stmts is important.]
391 	 */
392 		else if (LOOK_AHEAD(t,lquote)) {	/* strip quotes */
393 			nlpar = 0;
394 			record(quotes, nlpar++);
395 			/*
396 			 * Opening quote: scan forward until matching
397 			 * closing quote has been found.
398 			 */
399 			do {
400 
401 				l = gpbc();
402 				if (LOOK_AHEAD(l,rquote)) {
403 					if (--nlpar > 0)
404 						outputstr(rquote);
405 				} else if (LOOK_AHEAD(l,lquote)) {
406 					record(quotes, nlpar++);
407 					outputstr(lquote);
408 				} else if (l == EOF) {
409 					if (nlpar == 1)
410 						warnx("unclosed quote:");
411 					else
412 						warnx("%d unclosed quotes:", nlpar);
413 					dump_stack(quotes, nlpar);
414 					exit(1);
415 				} else {
416 					if (nlpar > 0) {
417 						if (sp < 0)
418 							putc(l, active);
419 						else
420 							CHRSAVE(l);
421 					}
422 				}
423 			}
424 			while (nlpar != 0);
425 		}
426 
427 		else if (sp < 0 && LOOK_AHEAD(t, scommt)) {
428 			fputs(scommt, active);
429 
430 			for(;;) {
431 				t = gpbc();
432 				if (LOOK_AHEAD(t, ecommt)) {
433 					fputs(ecommt, active);
434 					break;
435 				}
436 				if (t == EOF)
437 					break;
438 				putc(t, active);
439 			}
440 		}
441 
442 		else if (sp < 0) {		/* not in a macro at all */
443 			putc(t, active);	/* output directly..	 */
444 		}
445 
446 		else switch(t) {
447 
448 		case LPAREN:
449 			if (PARLEV > 0)
450 				chrsave(t);
451 			while (isspace(l = gpbc()))
452 				;		/* skip blank, tab, nl.. */
453 			putback(l);
454 			record(paren, PARLEV++);
455 			break;
456 
457 		case RPAREN:
458 			if (--PARLEV > 0)
459 				chrsave(t);
460 			else {			/* end of argument list */
461 				chrsave(EOS);
462 
463 				if ((uintptr_t)sp == STACKMAX)
464 					errx(1, "internal stack overflow");
465 
466 				eval((const char **) mstack+fp+1, sp-fp,
467 				    CALTYP);
468 
469 				ep = PREVEP;	/* flush strspace */
470 				sp = PREVSP;	/* previous sp..  */
471 				fp = PREVFP;	/* rewind stack...*/
472 			}
473 			break;
474 
475 		case COMMA:
476 			if (PARLEV == 1) {
477 				chrsave(EOS);		/* new argument   */
478 				while (isspace(l = gpbc()))
479 					;
480 				putback(l);
481 				pushs(ep);
482 			} else
483 				chrsave(t);
484 			break;
485 
486 		default:
487 			if (LOOK_AHEAD(t, scommt)) {
488 				char *pc;
489 				for (pc = scommt; *pc; pc++)
490 					chrsave(*pc);
491 				for(;;) {
492 					t = gpbc();
493 					if (LOOK_AHEAD(t, ecommt)) {
494 						for (pc = ecommt; *pc; pc++)
495 							chrsave(*pc);
496 						break;
497 					}
498 					if (t == EOF)
499 					    break;
500 					CHRSAVE(t);
501 				}
502 			} else
503 				CHRSAVE(t);		/* stack the char */
504 			break;
505 		}
506 	}
507 }
508 
509 /*
510  * output string directly, without pushing it for reparses.
511  */
512 void
513 outputstr(const char *s)
514 {
515 	if (sp < 0)
516 		while (*s)
517 			putc(*s++, active);
518 	else
519 		while (*s)
520 			CHRSAVE(*s++);
521 }
522 
523 /*
524  * build an input token..
525  * consider only those starting with _ or A-Za-z. This is a
526  * combo with lookup to speed things up.
527  */
528 static ndptr
529 inspect(int c, char *tp)
530 {
531 	char *name = tp;
532 	char *etp = tp+MAXTOK;
533 	ndptr p;
534 	unsigned int h;
535 
536 	h = *tp++ = c;
537 
538 	while ((isalnum(c = gpbc()) || c == '_') && tp < etp)
539 		h = (h << 5) + h + (*tp++ = c);
540 	if (c != EOF)
541 		PUTBACK(c);
542 	*tp = EOS;
543 	/* token is too long, it won't match anything, but it can still
544 	 * be output. */
545 	if (tp == ep) {
546 		outputstr(name);
547 		while (isalnum(c = gpbc()) || c == '_') {
548 			if (sp < 0)
549 				putc(c, active);
550 			else
551 				CHRSAVE(c);
552 		}
553 		*name = EOS;
554 		return nil;
555 	}
556 
557 	for (p = hashtab[h % HASHSIZE]; p != nil; p = p->nxtptr)
558 		if (h == p->hv && STREQ(name, p->name))
559 			break;
560 	return p;
561 }
562 
563 /*
564  * initkwds - initialise m4 keywords as fast as possible.
565  * This very similar to install, but without certain overheads,
566  * such as calling lookup. Malloc is not used for storing the
567  * keyword strings, since we simply use the static pointers
568  * within keywrds block.
569  */
570 static void
571 initkwds(void)
572 {
573 	size_t i;
574 	unsigned int h;
575 	ndptr p;
576 
577 	for (i = 0; i < MAXKEYS; i++) {
578 		h = hash(keywrds[i].knam);
579 		p = (ndptr) xalloc(sizeof(struct ndblock));
580 		p->nxtptr = hashtab[h % HASHSIZE];
581 		hashtab[h % HASHSIZE] = p;
582 		p->name = xstrdup(keywrds[i].knam);
583 		p->defn = xstrdup(null);
584 		p->hv = h;
585 		p->type = keywrds[i].ktyp & TYPEMASK;
586 		if ((keywrds[i].ktyp & NOARGS) == 0)
587 			p->type |= NEEDARGS;
588 	}
589 }
590 
591 /* Look up a builtin type, even if overridden by the user */
592 int
593 builtin_type(const char *key)
594 {
595 	int i;
596 
597 	for (i = 0; i != MAXKEYS; i++)
598 		if (STREQ(keywrds[i].knam, key))
599 			return keywrds[i].ktyp;
600 	return -1;
601 }
602 
603 const char *
604 builtin_realname(int n)
605 {
606 	int i;
607 
608 	for (i = 0; i != MAXKEYS; i++)
609 		if (((keywrds[i].ktyp ^ n) & TYPEMASK) == 0)
610 			return keywrds[i].knam;
611 	return NULL;
612 }
613 
614 static void
615 record(struct position *t, int lev)
616 {
617 	if (lev < MAXRECORD) {
618 		t[lev].name = CURRENT_NAME;
619 		t[lev].line = CURRENT_LINE;
620 	}
621 }
622 
623 static void
624 dump_stack(struct position *t, int lev)
625 {
626 	int i;
627 
628 	for (i = 0; i < lev; i++) {
629 		if (i == MAXRECORD) {
630 			fprintf(stderr, "   ...\n");
631 			break;
632 		}
633 		fprintf(stderr, "   %s at line %lu\n",
634 			t[i].name, t[i].line);
635 	}
636 }
637 
638 
639 static void
640 enlarge_stack(void)
641 {
642 	STACKMAX *= 2;
643 	mstack = realloc(mstack, sizeof(stae) * STACKMAX);
644 	sstack = realloc(sstack, STACKMAX);
645 	if (mstack == NULL || sstack == NULL)
646 		errx(1, "Evaluation stack overflow (%lu)",
647 		    (unsigned long)STACKMAX);
648 }
649 
650 /* Emit preprocessor #line directive if -s option used. */
651 void
652 emitline(void)
653 {
654 
655 	if (synccpp)
656 		fprintf(active, "#line %d \"%s\"\n", inlineno[ilevel],
657 			inname[ilevel]);
658 }
659