xref: /openbsd-src/usr.bin/m4/main.c (revision db3296cf5c1dd9058ceecc3a29fe4aaa0bd26000)
1 /*	$OpenBSD: main.c,v 1.63 2003/06/30 22:13:32 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. 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 static char rcsid[] = "$OpenBSD: main.c,v 1.63 2003/06/30 22:13:32 espie Exp $";
47 #endif
48 #endif /* not lint */
49 
50 /*
51  * main.c
52  * Facility: m4 macro processor
53  * by: oz
54  */
55 
56 #include <sys/types.h>
57 #include <assert.h>
58 #include <signal.h>
59 #include <errno.h>
60 #include <unistd.h>
61 #include <stdio.h>
62 #include <ctype.h>
63 #include <string.h>
64 #include <stddef.h>
65 #include <stdlib.h>
66 #include <ohash.h>
67 #include <err.h>
68 #include "mdef.h"
69 #include "stdd.h"
70 #include "extern.h"
71 #include "pathnames.h"
72 
73 ndptr hashtab[HASHSIZE];	/* hash table for macros etc.  */
74 stae *mstack;		 	/* stack of m4 machine         */
75 char *sstack;		 	/* shadow stack, for string space extension */
76 static size_t STACKMAX;		/* current maximum size of stack */
77 int sp; 			/* current m4  stack pointer   */
78 int fp; 			/* m4 call frame pointer       */
79 struct input_file infile[MAXINP];/* input file stack (0=stdin)  */
80 FILE **outfile;			/* diversion array(0=bitbucket)*/
81 int maxout;
82 FILE *active;			/* active output file pointer  */
83 int ilevel = 0; 		/* input file stack pointer    */
84 int oindex = 0; 		/* diversion index..	       */
85 char *null = "";                /* as it says.. just a null..  */
86 char *m4wraps = "";             /* m4wrap string default..     */
87 char lquote[MAXCCHARS+1] = {LQUOTE};	/* left quote character  (`)   */
88 char rquote[MAXCCHARS+1] = {RQUOTE};	/* right quote character (')   */
89 char scommt[MAXCCHARS+1] = {SCOMMT};	/* start character for comment */
90 char ecommt[MAXCCHARS+1] = {ECOMMT};	/* end character for comment   */
91 int  synch_lines = 0;		/* line synchronisation for C preprocessor */
92 
93 struct keyblk {
94         char    *knam;          /* keyword name */
95         int     ktyp;           /* keyword type */
96 };
97 
98 struct keyblk keywrds[] = {	/* m4 keywords to be installed */
99 	{ "include",      INCLTYPE },
100 	{ "sinclude",     SINCTYPE },
101 	{ "define",       DEFITYPE },
102 	{ "defn",         DEFNTYPE },
103 	{ "divert",       DIVRTYPE | NOARGS },
104 	{ "expr",         EXPRTYPE },
105 	{ "eval",         EXPRTYPE },
106 	{ "substr",       SUBSTYPE },
107 	{ "ifelse",       IFELTYPE },
108 	{ "ifdef",        IFDFTYPE },
109 	{ "len",          LENGTYPE },
110 	{ "incr",         INCRTYPE },
111 	{ "decr",         DECRTYPE },
112 	{ "dnl",          DNLNTYPE | NOARGS },
113 	{ "changequote",  CHNQTYPE | NOARGS },
114 	{ "changecom",    CHNCTYPE | NOARGS },
115 	{ "index",        INDXTYPE },
116 #ifdef EXTENDED
117 	{ "paste",        PASTTYPE },
118 	{ "spaste",       SPASTYPE },
119     	/* Newer extensions, needed to handle gnu-m4 scripts */
120 	{ "indir",        INDIRTYPE},
121 	{ "builtin",      BUILTINTYPE},
122 	{ "patsubst",	  PATSTYPE},
123 	{ "regexp",	  REGEXPTYPE},
124 	{ "esyscmd",	  ESYSCMDTYPE},
125 	{ "__file__",	  FILENAMETYPE | NOARGS},
126 	{ "__line__",	  LINETYPE | NOARGS},
127 #endif
128 	{ "popdef",       POPDTYPE },
129 	{ "pushdef",      PUSDTYPE },
130 	{ "dumpdef",      DUMPTYPE | NOARGS },
131 	{ "shift",        SHIFTYPE | NOARGS },
132 	{ "translit",     TRNLTYPE },
133 	{ "undefine",     UNDFTYPE },
134 	{ "undivert",     UNDVTYPE | NOARGS },
135 	{ "divnum",       DIVNTYPE | NOARGS },
136 	{ "maketemp",     MKTMTYPE },
137 	{ "errprint",     ERRPTYPE | NOARGS },
138 	{ "m4wrap",       M4WRTYPE | NOARGS },
139 	{ "m4exit",       EXITTYPE | NOARGS },
140 	{ "syscmd",       SYSCTYPE },
141 	{ "sysval",       SYSVTYPE | NOARGS },
142 	{ "traceon",	  TRACEONTYPE | NOARGS },
143 	{ "traceoff",	  TRACEOFFTYPE | NOARGS },
144 
145 #if defined(unix) || defined(__unix__)
146 	{ "unix",         SELFTYPE | NOARGS },
147 #else
148 #ifdef vms
149 	{ "vms",          SELFTYPE | NOARGS },
150 #endif
151 #endif
152 };
153 
154 #define MAXKEYS	(sizeof(keywrds)/sizeof(struct keyblk))
155 
156 extern int optind;
157 extern char *optarg;
158 
159 #define MAXRECORD 50
160 static struct position {
161 	char *name;
162 	unsigned long line;
163 } quotes[MAXRECORD], paren[MAXRECORD];
164 
165 static void record(struct position *, int);
166 static void dump_stack(struct position *, int);
167 
168 static void macro(void);
169 static void initkwds(void);
170 static ndptr inspect(int, char *);
171 static int do_look_ahead(int, const char *);
172 static void reallyoutputstr(const char *);
173 static void reallyputchar(int);
174 
175 static void enlarge_stack(void);
176 
177 int main(int, char *[]);
178 
179 int
180 main(int argc, char *argv[])
181 {
182 	int c;
183 	int n;
184 	char *p;
185 
186 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
187 		signal(SIGINT, onintr);
188 
189 	init_macros();
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 
204 		case 'D':               /* define something..*/
205 			for (p = optarg; *p; p++)
206 				if (*p == '=')
207 					break;
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 			macro_popdef(optarg);
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 			synch_lines = 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 			usage();
235 		}
236 
237         argc -= optind;
238         argv += optind;
239 
240 	active = stdout;		/* default active output     */
241 	bbase[0] = bufbase;
242         if (!argc) {
243  		sp = -1;		/* stack pointer initialized */
244 		fp = 0; 		/* frame pointer initialized */
245 		set_input(infile+0, stdin, "stdin");
246 					/* default input (naturally) */
247 		macro();
248 	} else
249 		for (; argc--; ++argv) {
250 			p = *argv;
251 			if (p[0] == '-' && p[1] == EOS)
252 				set_input(infile, stdin, "stdin");
253 			else if (fopen_trypath(infile, p) == NULL)
254 				err(1, "%s", p);
255 			sp = -1;
256 			fp = 0;
257 			macro();
258 		    	release_input(infile);
259 		}
260 
261 	if (*m4wraps) { 		/* anything for rundown ??   */
262 		ilevel = 0;		/* in case m4wrap includes.. */
263 		bufbase = bp = buf;	/* use the entire buffer   */
264 		pbstr(m4wraps); 	/* user-defined wrapup act   */
265 		macro();		/* last will and testament   */
266 	}
267 
268 	if (active != stdout)
269 		active = stdout;	/* reset output just in case */
270 	for (n = 1; n < maxout; n++)	/* default wrap-up: undivert */
271 		if (outfile[n] != NULL)
272 			getdiv(n);
273 					/* remove bitbucket if used  */
274 	if (outfile[0] != NULL) {
275 		(void) fclose(outfile[0]);
276 	}
277 
278 	return 0;
279 }
280 
281 /*
282  * Look ahead for `token'.
283  * (on input `t == token[0]')
284  * Used for comment and quoting delimiters.
285  * Returns 1 if `token' present; copied to output.
286  *         0 if `token' not found; all characters pushed back
287  */
288 static int
289 do_look_ahead(int t, const char *token)
290 {
291 	int i;
292 
293 	assert((unsigned char)t == (unsigned char)token[0]);
294 
295 	for (i = 1; *++token; i++) {
296 		t = gpbc();
297 		if (t == EOF || (unsigned char)t != (unsigned char)*token) {
298 			putback(t);
299 			while (--i)
300 				putback(*--token);
301 			return 0;
302 		}
303 	}
304 	return 1;
305 }
306 
307 #define LOOK_AHEAD(t, token) (t != EOF && 		\
308     (unsigned char)(t)==(unsigned char)(token)[0] && 	\
309     do_look_ahead(t,token))
310 
311 /*
312  * macro - the work horse..
313  */
314 static void
315 macro(void)
316 {
317 	char token[MAXTOK+1];
318 	int t, l;
319 	ndptr p;
320 	int  nlpar;
321 
322 	cycle {
323 		t = gpbc();
324 		if (t == '_' || isalpha(t)) {
325 			p = inspect(t, token);
326 			if (p != NULL)
327 				putback(l = gpbc());
328 			if (p == NULL || (l != LPAREN &&
329 			    (macro_getdef(p)->type & NEEDARGS) != 0))
330 				outputstr(token);
331 			else {
332 		/*
333 		 * real thing.. First build a call frame:
334 		 */
335 				pushf(fp);	/* previous call frm */
336 				pushf(macro_getdef(p)->type); /* type of the call  */
337 				pushf(is_traced(p));
338 				pushf(0);	/* parenthesis level */
339 				fp = sp;	/* new frame pointer */
340 		/*
341 		 * now push the string arguments:
342 		 */
343 				pushs1(macro_getdef(p)->defn);	/* defn string */
344 				pushs1((char *)macro_name(p));	/* macro name  */
345 				pushs(ep);	      	/* start next..*/
346 
347 				if (l != LPAREN && PARLEV == 0)  {
348 				    /* no bracks  */
349 					chrsave(EOS);
350 
351 					if (sp == STACKMAX)
352 						errx(1, "internal stack overflow");
353 					eval((const char **) mstack+fp+1, 2,
354 					    CALTYP, TRACESTATUS);
355 
356 					ep = PREVEP;	/* flush strspace */
357 					sp = PREVSP;	/* previous sp..  */
358 					fp = PREVFP;	/* rewind stack...*/
359 				}
360 			}
361 		} else if (t == EOF) {
362 			if (sp > -1) {
363 				warnx( "unexpected end of input, unclosed parenthesis:");
364 				dump_stack(paren, PARLEV);
365 				exit(1);
366 			}
367 			if (ilevel <= 0)
368 				break;			/* all done thanks.. */
369 			release_input(infile+ilevel--);
370 			emit_synchline();
371 			bufbase = bbase[ilevel];
372 			continue;
373 		}
374 	/*
375 	 * non-alpha token possibly seen..
376 	 * [the order of else if .. stmts is important.]
377 	 */
378 		else if (LOOK_AHEAD(t,lquote)) {	/* strip quotes */
379 			nlpar = 0;
380 			record(quotes, nlpar++);
381 			/*
382 			 * Opening quote: scan forward until matching
383 			 * closing quote has been found.
384 			 */
385 			do {
386 
387 				l = gpbc();
388 				if (LOOK_AHEAD(l,rquote)) {
389 					if (--nlpar > 0)
390 						outputstr(rquote);
391 				} else if (LOOK_AHEAD(l,lquote)) {
392 					record(quotes, nlpar++);
393 					outputstr(lquote);
394 				} else if (l == EOF) {
395 					if (nlpar == 1)
396 						warnx("unclosed quote:");
397 					else
398 						warnx("%d unclosed quotes:", nlpar);
399 					dump_stack(quotes, nlpar);
400 					exit(1);
401 				} else {
402 					if (nlpar > 0) {
403 						if (sp < 0)
404 							reallyputchar(l);
405 						else
406 							CHRSAVE(l);
407 					}
408 				}
409 			}
410 			while (nlpar != 0);
411 		}
412 
413 		else if (sp < 0 && LOOK_AHEAD(t, scommt)) {
414 			reallyoutputstr(scommt);
415 
416 			for(;;) {
417 				t = gpbc();
418 				if (LOOK_AHEAD(t, ecommt)) {
419 					reallyoutputstr(ecommt);
420 					break;
421 				}
422 				if (t == EOF)
423 					break;
424 				reallyputchar(t);
425 			}
426 		}
427 
428 		else if (sp < 0) {		/* not in a macro at all */
429 			reallyputchar(t);	/* output directly..	 */
430 		}
431 
432 		else switch(t) {
433 
434 		case LPAREN:
435 			if (PARLEV > 0)
436 				chrsave(t);
437 			while (isspace(l = gpbc()))
438 				;		/* skip blank, tab, nl.. */
439 			putback(l);
440 			record(paren, PARLEV++);
441 			break;
442 
443 		case RPAREN:
444 			if (--PARLEV > 0)
445 				chrsave(t);
446 			else {			/* end of argument list */
447 				chrsave(EOS);
448 
449 				if (sp == STACKMAX)
450 					errx(1, "internal stack overflow");
451 
452 				eval((const char **) mstack+fp+1, sp-fp,
453 				    CALTYP, TRACESTATUS);
454 
455 				ep = PREVEP;	/* flush strspace */
456 				sp = PREVSP;	/* previous sp..  */
457 				fp = PREVFP;	/* rewind stack...*/
458 			}
459 			break;
460 
461 		case COMMA:
462 			if (PARLEV == 1) {
463 				chrsave(EOS);		/* new argument   */
464 				while (isspace(l = gpbc()))
465 					;
466 				putback(l);
467 				pushs(ep);
468 			} else
469 				chrsave(t);
470 			break;
471 
472 		default:
473 			if (LOOK_AHEAD(t, scommt)) {
474 				char *p;
475 				for (p = scommt; *p; p++)
476 					chrsave(*p);
477 				for(;;) {
478 					t = gpbc();
479 					if (LOOK_AHEAD(t, ecommt)) {
480 						for (p = ecommt; *p; p++)
481 							chrsave(*p);
482 						break;
483 					}
484 					if (t == EOF)
485 					    break;
486 					CHRSAVE(t);
487 				}
488 			} else
489 				CHRSAVE(t);		/* stack the char */
490 			break;
491 		}
492 	}
493 }
494 
495 /*
496  * output string directly, without pushing it for reparses.
497  */
498 void
499 outputstr(const char *s)
500 {
501 	if (sp < 0)
502 		reallyoutputstr(s);
503 	else
504 		while (*s)
505 			CHRSAVE(*s++);
506 }
507 
508 void
509 reallyoutputstr(const char *s)
510 {
511 	if (synch_lines) {
512 		while (*s) {
513 			fputc(*s, active);
514 			if (*s++ == '\n') {
515 				infile[ilevel].synch_lineno++;
516 				if (infile[ilevel].synch_lineno !=
517 				    infile[ilevel].lineno)
518 					do_emit_synchline();
519 			}
520 		}
521 	} else
522 		fputs(s, active);
523 }
524 
525 void
526 reallyputchar(int c)
527 {
528 	putc(c, active);
529 	if (synch_lines && c == '\n') {
530 		infile[ilevel].synch_lineno++;
531 		if (infile[ilevel].synch_lineno != infile[ilevel].lineno)
532 			do_emit_synchline();
533 	}
534 }
535 
536 /*
537  * build an input token..
538  * consider only those starting with _ or A-Za-z.
539  */
540 static ndptr
541 inspect(int c, char *tp)
542 {
543 	char *name = tp;
544 	char *etp = tp+MAXTOK;
545 	ndptr p;
546 	unsigned int h;
547 
548 	*tp++ = c;
549 
550 	while ((isalnum(c = gpbc()) || c == '_') && tp < etp)
551 		*tp++ = c;
552 	if (c != EOF)
553 		PUTBACK(c);
554 	*tp = EOS;
555 	/* token is too long, it won't match anything, but it can still
556 	 * be output. */
557 	if (tp == ep) {
558 		outputstr(name);
559 		while (isalnum(c = gpbc()) || c == '_') {
560 			if (sp < 0)
561 				reallyputchar(c);
562 			else
563 				CHRSAVE(c);
564 		}
565 		*name = EOS;
566 		return NULL;
567 	}
568 
569 	p = ohash_find(&macros, ohash_qlookupi(&macros, name, (const char **)&tp));
570 	if (p == NULL)
571 		return NULL;
572 	if (macro_getdef(p) == NULL)
573 		return NULL;
574 	return p;
575 }
576 
577 /*
578  * initkwds - initialise m4 keywords as fast as possible.
579  * This very similar to install, but without certain overheads,
580  * such as calling lookup. Malloc is not used for storing the
581  * keyword strings, since we simply use the static pointers
582  * within keywrds block.
583  */
584 static void
585 initkwds(void)
586 {
587 	unsigned int type;
588 	int i;
589 
590 	for (i = 0; i < MAXKEYS; i++) {
591 		type = keywrds[i].ktyp & TYPEMASK;
592 		if ((keywrds[i].ktyp & NOARGS) == 0)
593 			type |= NEEDARGS;
594 		setup_builtin(keywrds[i].knam, type);
595 	}
596 }
597 
598 static void
599 record(struct position *t, int lev)
600 {
601 	if (lev < MAXRECORD) {
602 		t[lev].name = CURRENT_NAME;
603 		t[lev].line = CURRENT_LINE;
604 	}
605 }
606 
607 static void
608 dump_stack(struct position *t, int lev)
609 {
610 	int i;
611 
612 	for (i = 0; i < lev; i++) {
613 		if (i == MAXRECORD) {
614 			fprintf(stderr, "   ...\n");
615 			break;
616 		}
617 		fprintf(stderr, "   %s at line %lu\n",
618 			t[i].name, t[i].line);
619 	}
620 }
621 
622 
623 static void
624 enlarge_stack(void)
625 {
626 	STACKMAX *= 2;
627 	mstack = realloc(mstack, sizeof(stae) * STACKMAX);
628 	sstack = realloc(sstack, STACKMAX);
629 	if (mstack == NULL || sstack == NULL)
630 		errx(1, "Evaluation stack overflow (%lu)",
631 		    (unsigned long)STACKMAX);
632 }
633