xref: /openbsd-src/usr.bin/m4/main.c (revision 43003dfe3ad45d1698bed8a37f2b0f5b14f20d4f)
1 /*	$OpenBSD: main.c,v 1.76 2008/08/16 12:21:46 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 /*
37  * main.c
38  * Facility: m4 macro processor
39  * by: oz
40  */
41 
42 #include <assert.h>
43 #include <signal.h>
44 #include <err.h>
45 #include <errno.h>
46 #include <unistd.h>
47 #include <stdio.h>
48 #include <ctype.h>
49 #include <string.h>
50 #include <stddef.h>
51 #include <stdint.h>
52 #include <stdlib.h>
53 #include <ohash.h>
54 #include "mdef.h"
55 #include "stdd.h"
56 #include "extern.h"
57 #include "pathnames.h"
58 
59 ndptr hashtab[HASHSIZE];	/* hash table for macros etc.  */
60 stae *mstack;		 	/* stack of m4 machine         */
61 char *sstack;		 	/* shadow stack, for string space extension */
62 static size_t STACKMAX;		/* current maximum size of stack */
63 int sp; 			/* current m4  stack pointer   */
64 int fp; 			/* m4 call frame pointer       */
65 struct input_file infile[MAXINP];/* input file stack (0=stdin)  */
66 FILE **outfile;			/* diversion array(0=bitbucket)*/
67 int maxout;
68 FILE *active;			/* active output file pointer  */
69 int ilevel = 0; 		/* input file stack pointer    */
70 int oindex = 0; 		/* diversion index..	       */
71 char *null = "";                /* as it says.. just a null..  */
72 char **m4wraps = NULL;		/* m4wraps array.     	       */
73 int maxwraps = 0;		/* size of m4wraps array       */
74 int wrapindex = 0;		/* current offset in m4wraps   */
75 char lquote[MAXCCHARS+1] = {LQUOTE};	/* left quote character  (`)   */
76 char rquote[MAXCCHARS+1] = {RQUOTE};	/* right quote character (')   */
77 char scommt[MAXCCHARS+1] = {SCOMMT};	/* start character for comment */
78 char ecommt[MAXCCHARS+1] = {ECOMMT};	/* end character for comment   */
79 int  synch_lines = 0;		/* line synchronisation for C preprocessor */
80 
81 struct keyblk {
82         char    *knam;          /* keyword name */
83         int     ktyp;           /* keyword type */
84 };
85 
86 struct keyblk keywrds[] = {	/* m4 keywords to be installed */
87 	{ "include",      INCLTYPE },
88 	{ "sinclude",     SINCTYPE },
89 	{ "define",       DEFITYPE },
90 	{ "defn",         DEFNTYPE },
91 	{ "divert",       DIVRTYPE | NOARGS },
92 	{ "expr",         EXPRTYPE },
93 	{ "eval",         EXPRTYPE },
94 	{ "substr",       SUBSTYPE },
95 	{ "ifelse",       IFELTYPE },
96 	{ "ifdef",        IFDFTYPE },
97 	{ "len",          LENGTYPE },
98 	{ "incr",         INCRTYPE },
99 	{ "decr",         DECRTYPE },
100 	{ "dnl",          DNLNTYPE | NOARGS },
101 	{ "changequote",  CHNQTYPE | NOARGS },
102 	{ "changecom",    CHNCTYPE | NOARGS },
103 	{ "index",        INDXTYPE },
104 #ifdef EXTENDED
105 	{ "paste",        PASTTYPE },
106 	{ "spaste",       SPASTYPE },
107     	/* Newer extensions, needed to handle gnu-m4 scripts */
108 	{ "indir",        INDIRTYPE},
109 	{ "builtin",      BUILTINTYPE},
110 	{ "patsubst",	  PATSTYPE},
111 	{ "regexp",	  REGEXPTYPE},
112 	{ "esyscmd",	  ESYSCMDTYPE},
113 	{ "__file__",	  FILENAMETYPE | NOARGS},
114 	{ "__line__",	  LINETYPE | NOARGS},
115 #endif
116 	{ "popdef",       POPDTYPE },
117 	{ "pushdef",      PUSDTYPE },
118 	{ "dumpdef",      DUMPTYPE | NOARGS },
119 	{ "shift",        SHIFTYPE | NOARGS },
120 	{ "translit",     TRNLTYPE },
121 	{ "undefine",     UNDFTYPE },
122 	{ "undivert",     UNDVTYPE | NOARGS },
123 	{ "divnum",       DIVNTYPE | NOARGS },
124 	{ "maketemp",     MKTMTYPE },
125 	{ "errprint",     ERRPTYPE | NOARGS },
126 	{ "m4wrap",       M4WRTYPE | NOARGS },
127 	{ "m4exit",       EXITTYPE | NOARGS },
128 	{ "syscmd",       SYSCTYPE },
129 	{ "sysval",       SYSVTYPE | NOARGS },
130 	{ "traceon",	  TRACEONTYPE | NOARGS },
131 	{ "traceoff",	  TRACEOFFTYPE | NOARGS },
132 
133 #if defined(unix) || defined(__unix__)
134 	{ "unix",         SELFTYPE | NOARGS },
135 #else
136 #ifdef vms
137 	{ "vms",          SELFTYPE | NOARGS },
138 #endif
139 #endif
140 };
141 
142 #define MAXKEYS	(sizeof(keywrds)/sizeof(struct keyblk))
143 
144 extern int optind;
145 extern char *optarg;
146 
147 #define MAXRECORD 50
148 static struct position {
149 	char *name;
150 	unsigned long line;
151 } quotes[MAXRECORD], paren[MAXRECORD];
152 
153 static void record(struct position *, int);
154 static void dump_stack(struct position *, int);
155 
156 static void macro(void);
157 static void initkwds(void);
158 static ndptr inspect(int, char *);
159 static int do_look_ahead(int, const char *);
160 static void reallyoutputstr(const char *);
161 static void reallyputchar(int);
162 
163 static void enlarge_stack(void);
164 
165 int main(int, char *[]);
166 
167 int
168 main(int argc, char *argv[])
169 {
170 	int c;
171 	int n;
172 	char *p;
173 
174 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
175 		signal(SIGINT, onintr);
176 
177 	init_macros();
178 	initkwds();
179 	initspaces();
180 	STACKMAX = INITSTACKMAX;
181 
182 	mstack = (stae *)xalloc(sizeof(stae) * STACKMAX, NULL);
183 	sstack = (char *)xalloc(STACKMAX, NULL);
184 
185 	maxout = 0;
186 	outfile = NULL;
187 	resizedivs(MAXOUT);
188 
189 	while ((c = getopt(argc, argv, "gst:d:D:U:o:I:")) != -1)
190 		switch(c) {
191 
192 		case 'D':               /* define something..*/
193 			for (p = optarg; *p; p++)
194 				if (*p == '=')
195 					break;
196 			if (*p)
197 				*p++ = EOS;
198 			dodefine(optarg, p);
199 			break;
200 		case 'I':
201 			addtoincludepath(optarg);
202 			break;
203 		case 'U':               /* undefine...       */
204 			macro_popdef(optarg);
205 			break;
206 		case 'g':
207 			mimic_gnu = 1;
208 			setup_builtin("format", FORMATTYPE);
209 			break;
210 		case 'd':
211 			set_trace_flags(optarg);
212 			break;
213 		case 's':
214 			synch_lines = 1;
215 			break;
216 		case 't':
217 			mark_traced(optarg, 1);
218 			break;
219 		case 'o':
220 			trace_file(optarg);
221                         break;
222 		case '?':
223 			usage();
224 		}
225 
226         argc -= optind;
227         argv += optind;
228 
229 	active = stdout;		/* default active output     */
230 	bbase[0] = bufbase;
231         if (!argc) {
232  		sp = -1;		/* stack pointer initialized */
233 		fp = 0; 		/* frame pointer initialized */
234 		set_input(infile+0, stdin, "stdin");
235 					/* default input (naturally) */
236 		macro();
237 	} else
238 		for (; argc--; ++argv) {
239 			p = *argv;
240 			if (p[0] == '-' && p[1] == EOS)
241 				set_input(infile, stdin, "stdin");
242 			else if (fopen_trypath(infile, p) == NULL)
243 				err(1, "%s", p);
244 			sp = -1;
245 			fp = 0;
246 			macro();
247 		    	release_input(infile);
248 		}
249 
250 	if (wrapindex) {
251 		int i;
252 
253 		ilevel = 0;		/* in case m4wrap includes.. */
254 		bufbase = bp = buf;	/* use the entire buffer   */
255 		if (mimic_gnu) {
256 			while (wrapindex != 0) {
257 				for (i = 0; i < wrapindex; i++)
258 					pbstr(m4wraps[i]);
259 				wrapindex =0;
260 				macro();
261 			}
262 		} else {
263 			for (i = 0; i < wrapindex; i++) {
264 				pbstr(m4wraps[i]);
265 				macro();
266 		    	}
267 		}
268 	}
269 
270 	if (active != stdout)
271 		active = stdout;	/* reset output just in case */
272 	for (n = 1; n < maxout; n++)	/* default wrap-up: undivert */
273 		if (outfile[n] != NULL)
274 			getdiv(n);
275 					/* remove bitbucket if used  */
276 	if (outfile[0] != NULL) {
277 		(void) fclose(outfile[0]);
278 	}
279 
280 	return 0;
281 }
282 
283 /*
284  * Look ahead for `token'.
285  * (on input `t == token[0]')
286  * Used for comment and quoting delimiters.
287  * Returns 1 if `token' present; copied to output.
288  *         0 if `token' not found; all characters pushed back
289  */
290 static int
291 do_look_ahead(int t, const char *token)
292 {
293 	int i;
294 
295 	assert((unsigned char)t == (unsigned char)token[0]);
296 
297 	for (i = 1; *++token; i++) {
298 		t = gpbc();
299 		if (t == EOF || (unsigned char)t != (unsigned char)*token) {
300 			pushback(t);
301 			while (--i)
302 				pushback(*--token);
303 			return 0;
304 		}
305 	}
306 	return 1;
307 }
308 
309 #define LOOK_AHEAD(t, token) (t != EOF && 		\
310     (unsigned char)(t)==(unsigned char)(token)[0] && 	\
311     do_look_ahead(t,token))
312 
313 /*
314  * macro - the work horse..
315  */
316 static void
317 macro(void)
318 {
319 	char token[MAXTOK+1];
320 	int t, l;
321 	ndptr p;
322 	int  nlpar;
323 
324 	cycle {
325 		t = gpbc();
326 
327 		if (LOOK_AHEAD(t,lquote)) {	/* strip quotes */
328 			nlpar = 0;
329 			record(quotes, nlpar++);
330 			/*
331 			 * Opening quote: scan forward until matching
332 			 * closing quote has been found.
333 			 */
334 			do {
335 
336 				l = gpbc();
337 				if (LOOK_AHEAD(l,rquote)) {
338 					if (--nlpar > 0)
339 						outputstr(rquote);
340 				} else if (LOOK_AHEAD(l,lquote)) {
341 					record(quotes, nlpar++);
342 					outputstr(lquote);
343 				} else if (l == EOF) {
344 					if (nlpar == 1)
345 						warnx("unclosed quote:");
346 					else
347 						warnx("%d unclosed quotes:", nlpar);
348 					dump_stack(quotes, nlpar);
349 					exit(1);
350 				} else {
351 					if (nlpar > 0) {
352 						if (sp < 0)
353 							reallyputchar(l);
354 						else
355 							CHRSAVE(l);
356 					}
357 				}
358 			}
359 			while (nlpar != 0);
360 		} else if (sp < 0 && LOOK_AHEAD(t, scommt)) {
361 			reallyoutputstr(scommt);
362 
363 			for(;;) {
364 				t = gpbc();
365 				if (LOOK_AHEAD(t, ecommt)) {
366 					reallyoutputstr(ecommt);
367 					break;
368 				}
369 				if (t == EOF)
370 					break;
371 				reallyputchar(t);
372 			}
373 		} else if (t == '_' || isalpha(t)) {
374 			p = inspect(t, token);
375 			if (p != NULL)
376 				pushback(l = gpbc());
377 			if (p == NULL || (l != LPAREN &&
378 			    (macro_getdef(p)->type & NEEDARGS) != 0))
379 				outputstr(token);
380 			else {
381 		/*
382 		 * real thing.. First build a call frame:
383 		 */
384 				pushf(fp);	/* previous call frm */
385 				pushf(macro_getdef(p)->type); /* type of the call  */
386 				pushf(is_traced(p));
387 				pushf(0);	/* parenthesis level */
388 				fp = sp;	/* new frame pointer */
389 		/*
390 		 * now push the string arguments:
391 		 */
392 				pushs1(macro_getdef(p)->defn);	/* defn string */
393 				pushs1((char *)macro_name(p));	/* macro name  */
394 				pushs(ep);	      	/* start next..*/
395 
396 				if (l != LPAREN && PARLEV == 0)  {
397 				    /* no bracks  */
398 					chrsave(EOS);
399 
400 					if (sp == STACKMAX)
401 						errx(1, "internal stack overflow");
402 					eval((const char **) mstack+fp+1, 2,
403 					    CALTYP, TRACESTATUS);
404 
405 					ep = PREVEP;	/* flush strspace */
406 					sp = PREVSP;	/* previous sp..  */
407 					fp = PREVFP;	/* rewind stack...*/
408 				}
409 			}
410 		} else if (t == EOF) {
411 			if (sp > -1 && ilevel <= 0) {
412 				warnx( "unexpected end of input, unclosed parenthesis:");
413 				dump_stack(paren, PARLEV);
414 				exit(1);
415 			}
416 			if (ilevel <= 0)
417 				break;			/* all done thanks.. */
418 			release_input(infile+ilevel--);
419 			emit_synchline();
420 			bufbase = bbase[ilevel];
421 			continue;
422 		} else if (sp < 0) {		/* not in a macro at all */
423 			reallyputchar(t);	/* output directly..	 */
424 		}
425 
426 		else switch(t) {
427 
428 		case LPAREN:
429 			if (PARLEV > 0)
430 				chrsave(t);
431 			while (isspace(l = gpbc())) /* skip blank, tab, nl.. */
432 				if (PARLEV > 0)
433 					chrsave(l);
434 			pushback(l);
435 			record(paren, PARLEV++);
436 			break;
437 
438 		case RPAREN:
439 			if (--PARLEV > 0)
440 				chrsave(t);
441 			else {			/* end of argument list */
442 				chrsave(EOS);
443 
444 				if (sp == STACKMAX)
445 					errx(1, "internal stack overflow");
446 
447 				eval((const char **) mstack+fp+1, sp-fp,
448 				    CALTYP, TRACESTATUS);
449 
450 				ep = PREVEP;	/* flush strspace */
451 				sp = PREVSP;	/* previous sp..  */
452 				fp = PREVFP;	/* rewind stack...*/
453 			}
454 			break;
455 
456 		case COMMA:
457 			if (PARLEV == 1) {
458 				chrsave(EOS);		/* new argument   */
459 				while (isspace(l = gpbc()))
460 					;
461 				pushback(l);
462 				pushs(ep);
463 			} else
464 				chrsave(t);
465 			break;
466 
467 		default:
468 			if (LOOK_AHEAD(t, scommt)) {
469 				char *p;
470 				for (p = scommt; *p; p++)
471 					chrsave(*p);
472 				for(;;) {
473 					t = gpbc();
474 					if (LOOK_AHEAD(t, ecommt)) {
475 						for (p = ecommt; *p; p++)
476 							chrsave(*p);
477 						break;
478 					}
479 					if (t == EOF)
480 					    break;
481 					CHRSAVE(t);
482 				}
483 			} else
484 				CHRSAVE(t);		/* stack the char */
485 			break;
486 		}
487 	}
488 }
489 
490 /*
491  * output string directly, without pushing it for reparses.
492  */
493 void
494 outputstr(const char *s)
495 {
496 	if (sp < 0)
497 		reallyoutputstr(s);
498 	else
499 		while (*s)
500 			CHRSAVE(*s++);
501 }
502 
503 void
504 reallyoutputstr(const char *s)
505 {
506 	if (synch_lines) {
507 		while (*s) {
508 			fputc(*s, active);
509 			if (*s++ == '\n') {
510 				infile[ilevel].synch_lineno++;
511 				if (infile[ilevel].synch_lineno !=
512 				    infile[ilevel].lineno)
513 					do_emit_synchline();
514 			}
515 		}
516 	} else
517 		fputs(s, active);
518 }
519 
520 void
521 reallyputchar(int c)
522 {
523 	putc(c, active);
524 	if (synch_lines && c == '\n') {
525 		infile[ilevel].synch_lineno++;
526 		if (infile[ilevel].synch_lineno != infile[ilevel].lineno)
527 			do_emit_synchline();
528 	}
529 }
530 
531 /*
532  * build an input token..
533  * consider only those starting with _ or A-Za-z.
534  */
535 static ndptr
536 inspect(int c, char *tp)
537 {
538 	char *name = tp;
539 	char *etp = tp+MAXTOK;
540 	ndptr p;
541 
542 	*tp++ = c;
543 
544 	while ((isalnum(c = gpbc()) || c == '_') && tp < etp)
545 		*tp++ = c;
546 	if (c != EOF)
547 		PUSHBACK(c);
548 	*tp = EOS;
549 	/* token is too long, it won't match anything, but it can still
550 	 * be output. */
551 	if (tp == ep) {
552 		outputstr(name);
553 		while (isalnum(c = gpbc()) || c == '_') {
554 			if (sp < 0)
555 				reallyputchar(c);
556 			else
557 				CHRSAVE(c);
558 		}
559 		*name = EOS;
560 		return NULL;
561 	}
562 
563 	p = ohash_find(&macros, ohash_qlookupi(&macros, name, (const char **)&tp));
564 	if (p == NULL)
565 		return NULL;
566 	if (macro_getdef(p) == NULL)
567 		return NULL;
568 	return p;
569 }
570 
571 /*
572  * initkwds - initialise m4 keywords as fast as possible.
573  * This very similar to install, but without certain overheads,
574  * such as calling lookup. Malloc is not used for storing the
575  * keyword strings, since we simply use the static pointers
576  * within keywrds block.
577  */
578 static void
579 initkwds(void)
580 {
581 	unsigned int type;
582 	int i;
583 
584 	for (i = 0; i < MAXKEYS; i++) {
585 		type = keywrds[i].ktyp & TYPEMASK;
586 		if ((keywrds[i].ktyp & NOARGS) == 0)
587 			type |= NEEDARGS;
588 		setup_builtin(keywrds[i].knam, type);
589 	}
590 }
591 
592 static void
593 record(struct position *t, int lev)
594 {
595 	if (lev < MAXRECORD) {
596 		t[lev].name = CURRENT_NAME;
597 		t[lev].line = CURRENT_LINE;
598 	}
599 }
600 
601 static void
602 dump_stack(struct position *t, int lev)
603 {
604 	int i;
605 
606 	for (i = 0; i < lev; i++) {
607 		if (i == MAXRECORD) {
608 			fprintf(stderr, "   ...\n");
609 			break;
610 		}
611 		fprintf(stderr, "   %s at line %lu\n",
612 			t[i].name, t[i].line);
613 	}
614 }
615 
616 
617 static void
618 enlarge_stack(void)
619 {
620 	STACKMAX += STACKMAX/2;
621 	mstack = xrealloc(mstack, sizeof(stae) * STACKMAX,
622 	    "Evaluation stack overflow (%lu)",
623 	    (unsigned long)STACKMAX);
624 	sstack = xrealloc(sstack, STACKMAX,
625 	    "Evaluation stack overflow (%lu)",
626 	    (unsigned long)STACKMAX);
627 }
628