xref: /freebsd/usr.bin/m4/main.c (revision ea906c4152774dff300bb26fbfc1e4188351c89a)
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 <locale.h>
77 #include "mdef.h"
78 #include "stdd.h"
79 #include "extern.h"
80 #include "pathnames.h"
81 
82 ndptr hashtab[HASHSIZE];	/* hash table for macros etc.  */
83 stae *mstack;		 	/* stack of m4 machine         */
84 char *sstack;		 	/* shadow stack, for string space extension */
85 static size_t STACKMAX;		/* current maximum size of stack */
86 int sp; 			/* current m4  stack pointer   */
87 int fp; 			/* m4 call frame pointer       */
88 struct input_file infile[MAXINP];/* input file stack (0=stdin)  */
89 char *inname[MAXINP];		/* names of these input files */
90 int inlineno[MAXINP];		/* current number in each input file */
91 FILE **outfile;			/* diversion array(0=bitbucket)*/
92 int maxout;
93 FILE *active;			/* active output file pointer  */
94 int ilevel = 0; 		/* input file stack pointer    */
95 int oindex = 0; 		/* diversion index..	       */
96 char null[] = "";		/* as it says.. just a null..  */
97 const char *m4wraps = "";       /* m4wrap string default..     */
98 char lquote[MAXCCHARS+1] = {LQUOTE};	/* left quote character  (`)   */
99 char rquote[MAXCCHARS+1] = {RQUOTE};	/* right quote character (')   */
100 char scommt[MAXCCHARS+1] = {SCOMMT};	/* start character for comment */
101 char ecommt[MAXCCHARS+1] = {ECOMMT};	/* end character for comment   */
102 int synccpp;			/* Line synchronisation for C preprocessor */
103 
104 struct keyblk keywrds[] = {	/* m4 keywords to be installed */
105 	{ "include",      INCLTYPE },
106 	{ "sinclude",     SINCTYPE },
107 	{ "define",       DEFITYPE },
108 	{ "defn",         DEFNTYPE },
109 	{ "divert",       DIVRTYPE | NOARGS },
110 	{ "expr",         EXPRTYPE },
111 	{ "eval",         EXPRTYPE },
112 	{ "substr",       SUBSTYPE },
113 	{ "ifelse",       IFELTYPE },
114 	{ "ifdef",        IFDFTYPE },
115 	{ "len",          LENGTYPE },
116 	{ "incr",         INCRTYPE },
117 	{ "decr",         DECRTYPE },
118 	{ "dnl",          DNLNTYPE | NOARGS },
119 	{ "changequote",  CHNQTYPE | NOARGS },
120 	{ "changecom",    CHNCTYPE | NOARGS },
121 	{ "index",        INDXTYPE },
122 #ifdef EXTENDED
123 	{ "paste",        PASTTYPE },
124 	{ "spaste",       SPASTYPE },
125     	/* Newer extensions, needed to handle gnu-m4 scripts */
126 	{ "indir",        INDIRTYPE},
127 	{ "builtin",      BUILTINTYPE},
128 	{ "patsubst",	  PATSTYPE},
129 	{ "regexp",	  REGEXPTYPE},
130 	{ "esyscmd",	  ESYSCMDTYPE},
131 	{ "__file__",	  FILENAMETYPE | NOARGS},
132 	{ "__line__",	  LINETYPE | NOARGS},
133 #endif
134 	{ "popdef",       POPDTYPE },
135 	{ "pushdef",      PUSDTYPE },
136 	{ "dumpdef",      DUMPTYPE | NOARGS },
137 	{ "shift",        SHIFTYPE | NOARGS },
138 	{ "translit",     TRNLTYPE },
139 	{ "undefine",     UNDFTYPE },
140 	{ "undivert",     UNDVTYPE | NOARGS },
141 	{ "divnum",       DIVNTYPE | NOARGS },
142 	{ "maketemp",     MKTMTYPE },
143 	{ "errprint",     ERRPTYPE | NOARGS },
144 	{ "m4wrap",       M4WRTYPE | NOARGS },
145 	{ "m4exit",       EXITTYPE | NOARGS },
146 	{ "syscmd",       SYSCTYPE },
147 	{ "sysval",       SYSVTYPE | NOARGS },
148 	{ "traceon",	  TRACEONTYPE | NOARGS },
149 	{ "traceoff",	  TRACEOFFTYPE | NOARGS },
150 
151 #if defined(unix) || defined(__unix__)
152 	{ "unix",         SELFTYPE | NOARGS },
153 #else
154 #ifdef vms
155 	{ "vms",          SELFTYPE | NOARGS },
156 #endif
157 #endif
158 };
159 
160 #define MAXKEYS	(sizeof(keywrds)/sizeof(struct keyblk))
161 
162 #define MAXRECORD 50
163 static struct position {
164 	char *name;
165 	unsigned long line;
166 } quotes[MAXRECORD], paren[MAXRECORD];
167 
168 static void record(struct position *, int);
169 static void dump_stack(struct position *, int);
170 
171 static void macro(void);
172 static void initkwds(void);
173 static ndptr inspect(int, char *);
174 static int do_look_ahead(int, const char *);
175 
176 static void enlarge_stack(void);
177 
178 int
179 main(int argc, char *argv[])
180 {
181 	int c;
182 	int n;
183 	int rval;
184 	char *p;
185 
186 	setlocale(LC_ALL, "");
187 
188 	traceout = stderr;
189 
190 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
191 		signal(SIGINT, onintr);
192 
193 	initkwds();
194 	initspaces();
195 	STACKMAX = INITSTACKMAX;
196 
197 	mstack = (stae *)xalloc(sizeof(stae) * STACKMAX);
198 	sstack = (char *)xalloc(STACKMAX);
199 
200 	maxout = 0;
201 	outfile = NULL;
202 	resizedivs(MAXOUT);
203 
204 	while ((c = getopt(argc, argv, "gst:d:D:U:o:I:")) != -1)
205 		switch(c) {
206 		case 'D':               /* define something..*/
207 			for (p = optarg; *p; p++)
208 				if (*p == '=')
209 					break;
210 			if (p == optarg)
211 				errx(1, "null variable cannot be defined");
212 			if (*p)
213 				*p++ = EOS;
214 			dodefine(optarg, p);
215 			break;
216 		case 'I':
217 			addtoincludepath(optarg);
218 			break;
219 		case 'U':               /* undefine...       */
220 			remhash(optarg, TOP);
221 			break;
222 		case 'g':
223 			mimic_gnu = 1;
224 			break;
225 		case 'd':
226 			set_trace_flags(optarg);
227 			break;
228 		case 's':
229 			synccpp = 1;
230 			break;
231 		case 't':
232 			mark_traced(optarg, 1);
233 			break;
234 		case 'o':
235 			trace_file(optarg);
236                         break;
237 		case '?':
238 		default:
239 			usage();
240 		}
241 
242         argc -= optind;
243         argv += optind;
244 
245 	rval = 0;
246 	active = stdout;		/* default active output     */
247 	bbase[0] = bufbase;
248         if (!argc) {
249  		sp = -1;		/* stack pointer initialized */
250 		fp = 0; 		/* frame pointer initialized */
251 		set_input(infile+0, stdin, "stdin");
252 					/* default input (naturally) */
253 		if ((inname[0] = strdup("-")) == NULL)
254 			err(1, NULL);
255 		inlineno[0] = 1;
256 		emitline();
257 		macro();
258 	} else
259 		for (; argc--; ++argv) {
260 			p = *argv;
261 			if (p[0] == '-' && p[1] == EOS)
262 				set_input(infile, stdin, "stdin");
263 			else if (fopen_trypath(infile, p) == NULL) {
264 				warn("%s", p);
265 				rval = 1;
266 				continue;
267 			}
268 			sp = -1;
269 			fp = 0;
270 			if ((inname[0] = strdup(p)) == NULL)
271 				err(1, NULL);
272 			inlineno[0] = 1;
273 			emitline();
274 			macro();
275 		    	release_input(infile);
276 		}
277 
278 	if (*m4wraps) { 		/* anything for rundown ??   */
279 		ilevel = 0;		/* in case m4wrap includes.. */
280 		bufbase = bp = buf;	/* use the entire buffer   */
281 		pbstr(m4wraps); 	/* user-defined wrapup act   */
282 		macro();		/* last will and testament   */
283 	}
284 
285 	if (active != stdout)
286 		active = stdout;	/* reset output just in case */
287 	for (n = 1; n < maxout; n++)	/* default wrap-up: undivert */
288 		if (outfile[n] != NULL)
289 			getdiv(n);
290 					/* remove bitbucket if used  */
291 	if (outfile[0] != NULL) {
292 		(void) fclose(outfile[0]);
293 	}
294 
295 	exit(rval);
296 }
297 
298 /*
299  * Look ahead for `token'.
300  * (on input `t == token[0]')
301  * Used for comment and quoting delimiters.
302  * Returns 1 if `token' present; copied to output.
303  *         0 if `token' not found; all characters pushed back
304  */
305 static int
306 do_look_ahead(int t, const char *token)
307 {
308 	int i;
309 
310 	assert((unsigned char)t == (unsigned char)token[0]);
311 
312 	for (i = 1; *++token; i++) {
313 		t = gpbc();
314 		if (t == EOF || (unsigned char)t != (unsigned char)*token) {
315 			putback(t);
316 			while (--i)
317 				putback(*--token);
318 			return 0;
319 		}
320 	}
321 	return 1;
322 }
323 
324 #define LOOK_AHEAD(t, token) (t != EOF && 		\
325     (unsigned char)(t)==(unsigned char)(token)[0] && 	\
326     do_look_ahead(t,token))
327 
328 /*
329  * macro - the work horse..
330  */
331 static void
332 macro(void)
333 {
334 	char token[MAXTOK+1];
335 	int t, l;
336 	ndptr p;
337 	int  nlpar;
338 
339 	cycle {
340 		t = gpbc();
341 		if (t == '_' || isalpha(t)) {
342 			p = inspect(t, token);
343 			if (p != nil)
344 				putback(l = gpbc());
345 			if (p == nil || (l != LPAREN &&
346 			    (p->type & NEEDARGS) != 0))
347 				outputstr(token);
348 			else {
349 		/*
350 		 * real thing.. First build a call frame:
351 		 */
352 				pushf(fp);	/* previous call frm */
353 				pushf(p->type); /* type of the call  */
354 				pushf(0);	/* parenthesis level */
355 				fp = sp;	/* new frame pointer */
356 		/*
357 		 * now push the string arguments:
358 		 */
359 				pushs1(p->defn);	/* defn string */
360 				pushs1(p->name);	/* macro name  */
361 				pushs(ep);	      	/* start next..*/
362 
363 				if (l != LPAREN && PARLEV == 0)  {
364 				    /* no bracks  */
365 					chrsave(EOS);
366 
367 					if ((uintptr_t)sp == STACKMAX)
368 						errx(1, "internal stack overflow");
369 					eval((const char **) mstack+fp+1, 2,
370 					    CALTYP);
371 
372 					ep = PREVEP;	/* flush strspace */
373 					sp = PREVSP;	/* previous sp..  */
374 					fp = PREVFP;	/* rewind stack...*/
375 				}
376 			}
377 		} else if (t == EOF) {
378 			if (sp > -1) {
379 				warnx( "unexpected end of input, unclosed parenthesis:");
380 				dump_stack(paren, PARLEV);
381 				exit(1);
382 			}
383 			if (ilevel <= 0)
384 				break;			/* all done thanks.. */
385 			release_input(infile+ilevel--);
386 			free(inname[ilevel+1]);
387 			bufbase = bbase[ilevel];
388 			emitline();
389 			continue;
390 		}
391 	/*
392 	 * non-alpha token possibly seen..
393 	 * [the order of else if .. stmts is important.]
394 	 */
395 		else if (LOOK_AHEAD(t,lquote)) {	/* strip quotes */
396 			nlpar = 0;
397 			record(quotes, nlpar++);
398 			/*
399 			 * Opening quote: scan forward until matching
400 			 * closing quote has been found.
401 			 */
402 			do {
403 
404 				l = gpbc();
405 				if (LOOK_AHEAD(l,rquote)) {
406 					if (--nlpar > 0)
407 						outputstr(rquote);
408 				} else if (LOOK_AHEAD(l,lquote)) {
409 					record(quotes, nlpar++);
410 					outputstr(lquote);
411 				} else if (l == EOF) {
412 					if (nlpar == 1)
413 						warnx("unclosed quote:");
414 					else
415 						warnx("%d unclosed quotes:", nlpar);
416 					dump_stack(quotes, nlpar);
417 					exit(1);
418 				} else {
419 					if (nlpar > 0) {
420 						if (sp < 0)
421 							putc(l, active);
422 						else
423 							CHRSAVE(l);
424 					}
425 				}
426 			}
427 			while (nlpar != 0);
428 		}
429 
430 		else if (sp < 0 && LOOK_AHEAD(t, scommt)) {
431 			fputs(scommt, active);
432 
433 			for(;;) {
434 				t = gpbc();
435 				if (LOOK_AHEAD(t, ecommt)) {
436 					fputs(ecommt, active);
437 					break;
438 				}
439 				if (t == EOF)
440 					break;
441 				putc(t, active);
442 			}
443 		}
444 
445 		else if (sp < 0) {		/* not in a macro at all */
446 			putc(t, active);	/* output directly..	 */
447 		}
448 
449 		else switch(t) {
450 
451 		case LPAREN:
452 			if (PARLEV > 0)
453 				chrsave(t);
454 			while (isspace(l = gpbc()))
455 				;		/* skip blank, tab, nl.. */
456 			putback(l);
457 			record(paren, PARLEV++);
458 			break;
459 
460 		case RPAREN:
461 			if (--PARLEV > 0)
462 				chrsave(t);
463 			else {			/* end of argument list */
464 				chrsave(EOS);
465 
466 				if ((uintptr_t)sp == STACKMAX)
467 					errx(1, "internal stack overflow");
468 
469 				eval((const char **) mstack+fp+1, sp-fp,
470 				    CALTYP);
471 
472 				ep = PREVEP;	/* flush strspace */
473 				sp = PREVSP;	/* previous sp..  */
474 				fp = PREVFP;	/* rewind stack...*/
475 			}
476 			break;
477 
478 		case COMMA:
479 			if (PARLEV == 1) {
480 				chrsave(EOS);		/* new argument   */
481 				while (isspace(l = gpbc()))
482 					;
483 				putback(l);
484 				pushs(ep);
485 			} else
486 				chrsave(t);
487 			break;
488 
489 		default:
490 			if (LOOK_AHEAD(t, scommt)) {
491 				char *pc;
492 				for (pc = scommt; *pc; pc++)
493 					chrsave(*pc);
494 				for(;;) {
495 					t = gpbc();
496 					if (LOOK_AHEAD(t, ecommt)) {
497 						for (pc = ecommt; *pc; pc++)
498 							chrsave(*pc);
499 						break;
500 					}
501 					if (t == EOF)
502 					    break;
503 					CHRSAVE(t);
504 				}
505 			} else
506 				CHRSAVE(t);		/* stack the char */
507 			break;
508 		}
509 	}
510 }
511 
512 /*
513  * output string directly, without pushing it for reparses.
514  */
515 void
516 outputstr(const char *s)
517 {
518 	if (sp < 0)
519 		while (*s)
520 			putc(*s++, active);
521 	else
522 		while (*s)
523 			CHRSAVE(*s++);
524 }
525 
526 /*
527  * build an input token..
528  * consider only those starting with _ or A-Za-z. This is a
529  * combo with lookup to speed things up.
530  */
531 static ndptr
532 inspect(int c, char *tp)
533 {
534 	char *name = tp;
535 	char *etp = tp+MAXTOK;
536 	ndptr p;
537 	unsigned int h;
538 
539 	h = *tp++ = c;
540 
541 	while ((isalnum(c = gpbc()) || c == '_') && tp < etp)
542 		h = (h << 5) + h + (*tp++ = c);
543 	if (c != EOF)
544 		PUTBACK(c);
545 	*tp = EOS;
546 	/* token is too long, it won't match anything, but it can still
547 	 * be output. */
548 	if (tp == ep) {
549 		outputstr(name);
550 		while (isalnum(c = gpbc()) || c == '_') {
551 			if (sp < 0)
552 				putc(c, active);
553 			else
554 				CHRSAVE(c);
555 		}
556 		*name = EOS;
557 		return nil;
558 	}
559 
560 	for (p = hashtab[h % HASHSIZE]; p != nil; p = p->nxtptr)
561 		if (h == p->hv && STREQ(name, p->name))
562 			break;
563 	return p;
564 }
565 
566 /*
567  * initkwds - initialise m4 keywords as fast as possible.
568  * This very similar to install, but without certain overheads,
569  * such as calling lookup. Malloc is not used for storing the
570  * keyword strings, since we simply use the static pointers
571  * within keywrds block.
572  */
573 static void
574 initkwds(void)
575 {
576 	size_t i;
577 	unsigned int h;
578 	ndptr p;
579 
580 	for (i = 0; i < MAXKEYS; i++) {
581 		h = hash(keywrds[i].knam);
582 		p = (ndptr) xalloc(sizeof(struct ndblock));
583 		p->nxtptr = hashtab[h % HASHSIZE];
584 		hashtab[h % HASHSIZE] = p;
585 		p->name = xstrdup(keywrds[i].knam);
586 		p->defn = null;
587 		p->hv = h;
588 		p->type = keywrds[i].ktyp & TYPEMASK;
589 		if ((keywrds[i].ktyp & NOARGS) == 0)
590 			p->type |= NEEDARGS;
591 	}
592 }
593 
594 /* Look up a builtin type, even if overridden by the user */
595 int
596 builtin_type(const char *key)
597 {
598 	int i;
599 
600 	for (i = 0; i != MAXKEYS; i++)
601 		if (STREQ(keywrds[i].knam, key))
602 			return keywrds[i].ktyp;
603 	return -1;
604 }
605 
606 const char *
607 builtin_realname(int n)
608 {
609 	int i;
610 
611 	for (i = 0; i != MAXKEYS; i++)
612 		if (((keywrds[i].ktyp ^ n) & TYPEMASK) == 0)
613 			return keywrds[i].knam;
614 	return NULL;
615 }
616 
617 static void
618 record(struct position *t, int lev)
619 {
620 	if (lev < MAXRECORD) {
621 		t[lev].name = CURRENT_NAME;
622 		t[lev].line = CURRENT_LINE;
623 	}
624 }
625 
626 static void
627 dump_stack(struct position *t, int lev)
628 {
629 	int i;
630 
631 	for (i = 0; i < lev; i++) {
632 		if (i == MAXRECORD) {
633 			fprintf(stderr, "   ...\n");
634 			break;
635 		}
636 		fprintf(stderr, "   %s at line %lu\n",
637 			t[i].name, t[i].line);
638 	}
639 }
640 
641 
642 static void
643 enlarge_stack(void)
644 {
645 	STACKMAX *= 2;
646 	mstack = realloc(mstack, sizeof(stae) * STACKMAX);
647 	sstack = realloc(sstack, STACKMAX);
648 	if (mstack == NULL || sstack == NULL)
649 		errx(1, "Evaluation stack overflow (%lu)",
650 		    (unsigned long)STACKMAX);
651 }
652 
653 /* Emit preprocessor #line directive if -s option used. */
654 void
655 emitline(void)
656 {
657 
658 	if (synccpp)
659 		fprintf(active, "#line %d \"%s\"\n", inlineno[ilevel],
660 			inname[ilevel]);
661 }
662