xref: /freebsd/usr.bin/m4/main.c (revision d8eb75b41884ff1a9e257ae68ccce691e7be4e3c)
1 /*	$OpenBSD: main.c,v 1.86 2015/11/03 16:21:47 deraadt 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 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 #include <assert.h>
45 #include <signal.h>
46 #include <err.h>
47 #include <errno.h>
48 #include <unistd.h>
49 #include <stdio.h>
50 #include <ctype.h>
51 #include <string.h>
52 #include <stddef.h>
53 #include <stdint.h>
54 #include <stdlib.h>
55 #include <ohash.h>
56 #include "mdef.h"
57 #include "stdd.h"
58 #include "extern.h"
59 #include "pathnames.h"
60 
61 stae *mstack;			/* stack of m4 machine         */
62 char *sstack;			/* shadow stack, for string space extension */
63 static size_t STACKMAX;		/* current maximum size of stack */
64 int sp;				/* current m4  stack pointer   */
65 int fp;				/* m4 call frame pointer       */
66 struct input_file infile[MAXINP];/* input file stack (0=stdin)  */
67 FILE **outfile;			/* diversion array(0=bitbucket)*/
68 int maxout;
69 FILE *active;			/* active output file pointer  */
70 int ilevel = 0;			/* input file stack pointer    */
71 int oindex = 0;			/* diversion index..	       */
72 const char *null = "";                /* as it says.. just a null..  */
73 char **m4wraps = NULL;		/* m4wraps array.	       */
74 int maxwraps = 0;		/* size of m4wraps array       */
75 int wrapindex = 0;		/* current offset in m4wraps   */
76 char lquote[MAXCCHARS+1] = {LQUOTE};	/* left quote character  (`)   */
77 char rquote[MAXCCHARS+1] = {RQUOTE};	/* right quote character (')   */
78 char scommt[MAXCCHARS+1] = {SCOMMT};	/* start character for comment */
79 char ecommt[MAXCCHARS+1] = {ECOMMT};	/* end character for comment   */
80 int  synch_lines = 0;		/* line synchronisation for C preprocessor */
81 int  prefix_builtins = 0;	/* -P option to prefix builtin keywords */
82 
83 struct keyblk {
84         const char    *knam;          /* keyword name */
85         int     ktyp;           /* keyword type */
86 };
87 
88 static struct keyblk keywrds[] = {	/* m4 keywords to be installed */
89 	{ "include",      INCLTYPE },
90 	{ "sinclude",     SINCTYPE },
91 	{ "define",       DEFITYPE },
92 	{ "defn",         DEFNTYPE },
93 	{ "divert",       DIVRTYPE | NOARGS },
94 	{ "expr",         EXPRTYPE },
95 	{ "eval",         EXPRTYPE },
96 	{ "substr",       SUBSTYPE },
97 	{ "ifelse",       IFELTYPE },
98 	{ "ifdef",        IFDFTYPE },
99 	{ "len",          LENGTYPE },
100 	{ "incr",         INCRTYPE },
101 	{ "decr",         DECRTYPE },
102 	{ "dnl",          DNLNTYPE | NOARGS },
103 	{ "changequote",  CHNQTYPE | NOARGS },
104 	{ "changecom",    CHNCTYPE | NOARGS },
105 	{ "index",        INDXTYPE },
106 #ifdef EXTENDED
107 	{ "paste",        PASTTYPE },
108 	{ "spaste",       SPASTYPE },
109 	/* Newer extensions, needed to handle gnu-m4 scripts */
110 	{ "indir",        INDIRTYPE},
111 	{ "builtin",      BUILTINTYPE},
112 	{ "patsubst",	  PATSTYPE},
113 	{ "regexp",	  REGEXPTYPE},
114 	{ "esyscmd",	  ESYSCMDTYPE},
115 	{ "__file__",	  FILENAMETYPE | NOARGS},
116 	{ "__line__",	  LINETYPE | NOARGS},
117 #endif
118 	{ "popdef",       POPDTYPE },
119 	{ "pushdef",      PUSDTYPE },
120 	{ "dumpdef",      DUMPTYPE | NOARGS },
121 	{ "shift",        SHIFTYPE | NOARGS },
122 	{ "translit",     TRNLTYPE },
123 	{ "undefine",     UNDFTYPE },
124 	{ "undivert",     UNDVTYPE | NOARGS },
125 	{ "divnum",       DIVNTYPE | NOARGS },
126 	{ "maketemp",     MKTMTYPE },
127 	{ "mkstemp",      MKTMTYPE },
128 	{ "errprint",     ERRPTYPE | NOARGS },
129 	{ "m4wrap",       M4WRTYPE | NOARGS },
130 	{ "m4exit",       EXITTYPE | NOARGS },
131 	{ "syscmd",       SYSCTYPE },
132 	{ "sysval",       SYSVTYPE | NOARGS },
133 	{ "traceon",	  TRACEONTYPE | NOARGS },
134 	{ "traceoff",	  TRACEOFFTYPE | NOARGS },
135 
136 	{ "unix",         SELFTYPE | NOARGS },
137 };
138 
139 #define MAXKEYS	(sizeof(keywrds)/sizeof(struct keyblk))
140 
141 extern int optind;
142 extern char *optarg;
143 
144 #define MAXRECORD 50
145 static struct position {
146 	char *name;
147 	unsigned long line;
148 } quotes[MAXRECORD], paren[MAXRECORD];
149 
150 static void record(struct position *, int);
151 static void dump_stack(struct position *, int);
152 
153 static void macro(void);
154 static void initkwds(void);
155 static ndptr inspect(int, char *);
156 static int do_look_ahead(int, const char *);
157 static void reallyoutputstr(const char *);
158 static void reallyputchar(int);
159 
160 static void enlarge_stack(void);
161 
162 int main(int, char *[]);
163 
164 int exit_code = 0;
165 
166 int
167 main(int argc, char *argv[])
168 {
169 	int c;
170 	int n;
171 	char *p;
172 
173 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
174 		signal(SIGINT, onintr);
175 
176 	init_macros();
177 	initspaces();
178 	STACKMAX = INITSTACKMAX;
179 
180 	mstack = xreallocarray(NULL, STACKMAX, sizeof(stae), NULL);
181 	sstack = xalloc(STACKMAX, NULL);
182 
183 	maxout = 0;
184 	outfile = NULL;
185 	resizedivs(MAXOUT);
186 
187 	while ((c = getopt(argc, argv, "gst:d:D:U:o:I:P")) != -1)
188 		switch(c) {
189 
190 		case 'D':               /* define something..*/
191 			for (p = optarg; *p; p++)
192 				if (*p == '=')
193 					break;
194 			if (*p)
195 				*p++ = EOS;
196 			dodefine(optarg, p);
197 			break;
198 		case 'I':
199 			addtoincludepath(optarg);
200 			break;
201 		case 'P':
202 			prefix_builtins = 1;
203 			break;
204 		case 'U':               /* undefine...       */
205 			macro_popdef(optarg);
206 			break;
207 		case 'g':
208 			mimic_gnu = 1;
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 	initkwds();
230 	if (mimic_gnu)
231 		setup_builtin("format", FORMATTYPE);
232 
233 	active = stdout;		/* default active output     */
234 	bbase[0] = bufbase;
235         if (!argc) {
236 		sp = -1;		/* stack pointer initialized */
237 		fp = 0;			/* frame pointer initialized */
238 		set_input(infile+0, stdin, "stdin");
239 					/* default input (naturally) */
240 		macro();
241 	} else
242 		for (; argc--; ++argv) {
243 			p = *argv;
244 			if (p[0] == '-' && p[1] == EOS)
245 				set_input(infile, stdin, "stdin");
246 			else if (fopen_trypath(infile, p) == NULL)
247 				err(1, "%s", p);
248 			sp = -1;
249 			fp = 0;
250 			macro();
251 			release_input(infile);
252 		}
253 
254 	if (wrapindex) {
255 		int i;
256 
257 		ilevel = 0;		/* in case m4wrap includes.. */
258 		bufbase = bp = buf;	/* use the entire buffer   */
259 		if (mimic_gnu) {
260 			while (wrapindex != 0) {
261 				for (i = 0; i < wrapindex; i++)
262 					pbstr(m4wraps[i]);
263 				wrapindex =0;
264 				macro();
265 			}
266 		} else {
267 			for (i = 0; i < wrapindex; i++) {
268 				pbstr(m4wraps[i]);
269 				macro();
270 			}
271 		}
272 	}
273 
274 	if (active != stdout)
275 		active = stdout;	/* reset output just in case */
276 	for (n = 1; n < maxout; n++)	/* default wrap-up: undivert */
277 		if (outfile[n] != NULL)
278 			getdiv(n);
279 					/* remove bitbucket if used  */
280 	if (outfile[0] != NULL) {
281 		(void) fclose(outfile[0]);
282 	}
283 
284 	return exit_code;
285 }
286 
287 /*
288  * Look ahead for `token'.
289  * (on input `t == token[0]')
290  * Used for comment and quoting delimiters.
291  * Returns 1 if `token' present; copied to output.
292  *         0 if `token' not found; all characters pushed back
293  */
294 static int
295 do_look_ahead(int t, const char *token)
296 {
297 	int i;
298 
299 	assert((unsigned char)t == (unsigned char)token[0]);
300 
301 	for (i = 1; *++token; i++) {
302 		t = gpbc();
303 		if (t == EOF || (unsigned char)t != (unsigned char)*token) {
304 			pushback(t);
305 			while (--i)
306 				pushback(*--token);
307 			return 0;
308 		}
309 	}
310 	return 1;
311 }
312 
313 #define LOOK_AHEAD(t, token) (t != EOF &&		\
314     (unsigned char)(t)==(unsigned char)(token)[0] &&	\
315     do_look_ahead(t,token))
316 
317 /*
318  * macro - the work horse..
319  */
320 static void
321 macro(void)
322 {
323 	char token[MAXTOK+1];
324 	int t, l;
325 	ndptr p;
326 	int  nlpar;
327 
328 	cycle {
329 		t = gpbc();
330 
331 		if (LOOK_AHEAD(t,lquote)) {	/* strip quotes */
332 			nlpar = 0;
333 			record(quotes, nlpar++);
334 			/*
335 			 * Opening quote: scan forward until matching
336 			 * closing quote has been found.
337 			 */
338 			do {
339 
340 				l = gpbc();
341 				if (LOOK_AHEAD(l,rquote)) {
342 					if (--nlpar > 0)
343 						outputstr(rquote);
344 				} else if (LOOK_AHEAD(l,lquote)) {
345 					record(quotes, nlpar++);
346 					outputstr(lquote);
347 				} else if (l == EOF) {
348 					if (nlpar == 1)
349 						warnx("unclosed quote:");
350 					else
351 						warnx("%d unclosed quotes:", nlpar);
352 					dump_stack(quotes, nlpar);
353 					exit(1);
354 				} else {
355 					if (nlpar > 0) {
356 						if (sp < 0)
357 							reallyputchar(l);
358 						else
359 							CHRSAVE(l);
360 					}
361 				}
362 			}
363 			while (nlpar != 0);
364 		} else if (sp < 0 && LOOK_AHEAD(t, scommt)) {
365 			reallyoutputstr(scommt);
366 
367 			for(;;) {
368 				t = gpbc();
369 				if (LOOK_AHEAD(t, ecommt)) {
370 					reallyoutputstr(ecommt);
371 					break;
372 				}
373 				if (t == EOF)
374 					break;
375 				reallyputchar(t);
376 			}
377 		} else if (t == '_' || isalpha(t)) {
378 			p = inspect(t, token);
379 			if (p != NULL)
380 				pushback(l = gpbc());
381 			if (p == NULL || (l != LPAREN &&
382 			    (macro_getdef(p)->type & NEEDARGS) != 0))
383 				outputstr(token);
384 			else {
385 		/*
386 		 * real thing.. First build a call frame:
387 		 */
388 				pushf(fp);	/* previous call frm */
389 				pushf(macro_getdef(p)->type); /* type of the call  */
390 				pushf(is_traced(p));
391 				pushf(0);	/* parenthesis level */
392 				fp = sp;	/* new frame pointer */
393 		/*
394 		 * now push the string arguments:
395 		 */
396 				pushdef(p);			/* defn string */
397 				pushs1((char *)macro_name(p));	/* macro name  */
398 				pushs(ep);			/* start next..*/
399 
400 				if (l != LPAREN && PARLEV == 0) {
401 				    /* no bracks  */
402 					chrsave(EOS);
403 
404 					if (sp == (int)STACKMAX)
405 						errx(1, "internal stack overflow");
406 					eval((const char **) mstack+fp+1, 2,
407 					    CALTYP, TRACESTATUS);
408 
409 					ep = PREVEP;	/* flush strspace */
410 					sp = PREVSP;	/* previous sp..  */
411 					fp = PREVFP;	/* rewind stack...*/
412 				}
413 			}
414 		} else if (t == EOF) {
415 			if (!mimic_gnu /* you can puke right there */
416 			    && sp > -1 && ilevel <= 0) {
417 				warnx( "unexpected end of input, unclosed parenthesis:");
418 				dump_stack(paren, PARLEV);
419 				exit(1);
420 			}
421 			if (ilevel <= 0)
422 				break;			/* all done thanks.. */
423 			release_input(infile+ilevel--);
424 			emit_synchline();
425 			bufbase = bbase[ilevel];
426 			continue;
427 		} else if (sp < 0) {		/* not in a macro at all */
428 			reallyputchar(t);	/* output directly..	 */
429 		}
430 
431 		else switch(t) {
432 
433 		case LPAREN:
434 			if (PARLEV > 0)
435 				chrsave(t);
436 			while (isspace(l = gpbc())) /* skip blank, tab, nl.. */
437 				if (PARLEV > 0)
438 					chrsave(l);
439 			pushback(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 == (int)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 				pushback(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 
547 	*tp++ = c;
548 
549 	while ((isalnum(c = gpbc()) || c == '_') && tp < etp)
550 		*tp++ = c;
551 	if (c != EOF)
552 		PUSHBACK(c);
553 	*tp = EOS;
554 	/* token is too long, it won't match anything, but it can still
555 	 * be output. */
556 	if (tp == ep) {
557 		outputstr(name);
558 		while (isalnum(c = gpbc()) || c == '_') {
559 			if (sp < 0)
560 				reallyputchar(c);
561 			else
562 				CHRSAVE(c);
563 		}
564 		*name = EOS;
565 		return NULL;
566 	}
567 
568 	p = ohash_find(&macros, ohash_qlookupi(&macros, name, (const char **)&tp));
569 	if (p == NULL)
570 		return NULL;
571 	if (macro_getdef(p) == NULL)
572 		return NULL;
573 	return p;
574 }
575 
576 /*
577  * initkwds - initialise m4 keywords as fast as possible.
578  * This very similar to install, but without certain overheads,
579  * such as calling lookup. Malloc is not used for storing the
580  * keyword strings, since we simply use the static pointers
581  * within keywrds block.
582  */
583 static void
584 initkwds(void)
585 {
586 	unsigned int type;
587 	int i;
588 
589 	for (i = 0; i < (int)MAXKEYS; i++) {
590 		type = keywrds[i].ktyp & TYPEMASK;
591 		if ((keywrds[i].ktyp & NOARGS) == 0)
592 			type |= NEEDARGS;
593 		setup_builtin(keywrds[i].knam, type);
594 	}
595 }
596 
597 static void
598 record(struct position *t, int lev)
599 {
600 	if (lev < MAXRECORD) {
601 		t[lev].name = CURRENT_NAME;
602 		t[lev].line = CURRENT_LINE;
603 	}
604 }
605 
606 static void
607 dump_stack(struct position *t, int lev)
608 {
609 	int i;
610 
611 	for (i = 0; i < lev; i++) {
612 		if (i == MAXRECORD) {
613 			fprintf(stderr, "   ...\n");
614 			break;
615 		}
616 		fprintf(stderr, "   %s at line %lu\n",
617 			t[i].name, t[i].line);
618 	}
619 }
620 
621 
622 static void
623 enlarge_stack(void)
624 {
625 	STACKMAX += STACKMAX/2;
626 	mstack = xreallocarray(mstack, STACKMAX, sizeof(stae),
627 	    "Evaluation stack overflow (%lu)",
628 	    (unsigned long)STACKMAX);
629 	sstack = xrealloc(sstack, STACKMAX,
630 	    "Evaluation stack overflow (%lu)",
631 	    (unsigned long)STACKMAX);
632 }
633