summaryrefslogtreecommitdiffstats
path: root/usr.bin/m4/eval.c
blob: b1b2a391ddcc2f7ee78e3248d9f0107e1d59de42 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
/*
 * Copyright (c) 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ozan Yigit at York University.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)eval.c	8.1 (Berkeley) 6/6/93";
#endif /* not lint */

/*
 * eval.c
 * Facility: m4 macro processor
 * by: oz
 */

#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "mdef.h"
#include "stdd.h"
#include "extern.h"
#include "pathnames.h"

/*
 * eval - evaluate built-in macros.
 *	  argc - number of elements in argv.
 *	  argv - element vector :
 *			argv[0] = definition of a user
 *				  macro or nil if built-in.
 *			argv[1] = name of the macro or
 *				  built-in.
 *			argv[2] = parameters to user-defined
 *			   .	  macro or built-in.
 *			   .
 *
 * Note that the minimum value for argc is 3. A call in the form
 * of macro-or-builtin() will result in:
 *			argv[0] = nullstr
 *			argv[1] = macro-or-builtin
 *			argv[2] = nullstr
 */

void
eval(argv, argc, td)
register char *argv[];
register int argc;
register int td;
{
	register int c, n;
	static int sysval = 0;

#ifdef DEBUG
	printf("argc = %d\n", argc);
	for (n = 0; n < argc; n++)
		printf("argv[%d] = %s\n", n, argv[n]);
#endif
 /*
  * if argc == 3 and argv[2] is null, then we
  * have macro-or-builtin() type call. We adjust
  * argc to avoid further checking..
  */
	if (argc == 3 && !*(argv[2]))
		argc--;

	switch (td & ~STATIC) {

	case DEFITYPE:
		if (argc > 2)
			dodefine(argv[2], (argc > 3) ? argv[3] : null);
		break;

	case PUSDTYPE:
		if (argc > 2)
			dopushdef(argv[2], (argc > 3) ? argv[3] : null);
		break;

	case DUMPTYPE:
		dodump(argv, argc);
		break;

	case EXPRTYPE:
	/*
	 * doexpr - evaluate arithmetic
	 * expression
	 */
		if (argc > 2)
			pbnum(expr(argv[2]));
		break;

	case IFELTYPE:
		if (argc > 4)
			doifelse(argv, argc);
		break;

	case IFDFTYPE:
	/*
	 * doifdef - select one of two
	 * alternatives based on the existence of
	 * another definition
	 */
		if (argc > 3) {
			if (lookup(argv[2]) != nil)
				pbstr(argv[3]);
			else if (argc > 4)
				pbstr(argv[4]);
		}
		break;

	case LENGTYPE:
	/*
	 * dolen - find the length of the
	 * argument
	 */
		if (argc > 2)
			pbnum((argc > 2) ? strlen(argv[2]) : 0);
		break;

	case INCRTYPE:
	/*
	 * doincr - increment the value of the
	 * argument
	 */
		if (argc > 2)
			pbnum(atoi(argv[2]) + 1);
		break;

	case DECRTYPE:
	/*
	 * dodecr - decrement the value of the
	 * argument
	 */
		if (argc > 2)
			pbnum(atoi(argv[2]) - 1);
		break;

	case SYSCTYPE:
	/*
	 * dosys - execute system command
	 */
		/* Make sure m4 output is NOT interrupted */
		fflush(stdout);
		fflush(stderr);
		if (argc > 2)
			sysval = system(argv[2]);
		break;

	case SYSVTYPE:
	/*
	 * dosysval - return value of the last
	 * system call.
	 *
	 */
		pbnum(sysval);
		break;

	case INCLTYPE:
		if (argc > 2)
			if (!doincl(argv[2]))
				oops("%s: %s", argv[2], strerror(errno));
		break;

	case SINCTYPE:
		if (argc > 2)
			(void) doincl(argv[2]);
		break;
#ifdef EXTENDED
	case PASTTYPE:
		if (argc > 2)
			if (!dopaste(argv[2]))
				oops("%s: %s", argv[2], strerror(errno));
		break;

	case SPASTYPE:
		if (argc > 2)
			(void) dopaste(argv[2]);
		break;
#endif
	case CHNQTYPE:
		dochq(argv, argc);
		break;

	case CHNCTYPE:
		dochc(argv, argc);
		break;

	case SUBSTYPE:
	/*
	 * dosub - select substring
	 *
	 */
		if (argc > 3)
			dosub(argv, argc);
		break;

	case SHIFTYPE:
	/*
	 * doshift - push back all arguments
	 * except the first one (i.e. skip
	 * argv[2])
	 */
		if (argc > 3) {
			for (n = argc - 1; n > 3; n--) {
				putback(rquote);
				pbstr(argv[n]);
				putback(lquote);
				putback(',');
			}
			putback(rquote);
			pbstr(argv[3]);
			putback(lquote);
		}
		break;

	case DIVRTYPE:
		if (argc > 2 && (n = atoi(argv[2])) != 0)
			dodiv(n);
		else {
			active = stdout;
			oindex = 0;
		}
		break;

	case UNDVTYPE:
		doundiv(argv, argc);
		break;

	case DIVNTYPE:
	/*
	 * dodivnum - return the number of
	 * current output diversion
	 */
		pbnum(oindex);
		break;

	case UNDFTYPE:
	/*
	 * doundefine - undefine a previously
	 * defined macro(s) or m4 keyword(s).
	 */
		if (argc > 2)
			for (n = 2; n < argc; n++)
				remhash(argv[n], ALL);
		break;

	case POPDTYPE:
	/*
	 * dopopdef - remove the topmost
	 * definitions of macro(s) or m4
	 * keyword(s).
	 */
		if (argc > 2)
			for (n = 2; n < argc; n++)
				remhash(argv[n], TOP);
		break;

	case MKTMTYPE:
	/*
	 * dotemp - create a temporary file
	 */
		if (argc > 2)
			pbstr(mktemp(argv[2]));
		break;

	case TRNLTYPE:
	/*
	 * dotranslit - replace all characters in
	 * the source string that appears in the
	 * "from" string with the corresponding
	 * characters in the "to" string.
	 */
		if (argc > 3) {
			char temp[MAXTOK];
			if (argc > 4)
				map(temp, argv[2], argv[3], argv[4]);
			else
				map(temp, argv[2], argv[3], null);
			pbstr(temp);
		}
		else if (argc > 2)
			pbstr(argv[2]);
		break;

	case INDXTYPE:
	/*
	 * doindex - find the index of the second
	 * argument string in the first argument
	 * string. -1 if not present.
	 */
		pbnum((argc > 3) ? indx(argv[2], argv[3]) : -1);
		break;

	case ERRPTYPE:
	/*
	 * doerrp - print the arguments to stderr
	 * file
	 */
		if (argc > 2) {
			for (n = 2; n < argc; n++)
				fprintf(stderr, "%s ", argv[n]);
			fprintf(stderr, "\n");
		}
		break;

	case DNLNTYPE:
	/*
	 * dodnl - eat-up-to and including
	 * newline
	 */
		while ((c = gpbc()) != '\n' && c != EOF)
			;
		break;

	case M4WRTYPE:
	/*
	 * dom4wrap - set up for
	 * wrap-up/wind-down activity
	 */
		m4wraps = (argc > 2) ? xstrdup(argv[2]) : null;
		break;

	case EXITTYPE:
	/*
	 * doexit - immediate exit from m4.
	 */
		killdiv();
		exit((argc > 2) ? atoi(argv[2]) : 0);
		break;

	case DEFNTYPE:
		if (argc > 2)
			for (n = 2; n < argc; n++)
				dodefn(argv[n]);
		break;

	default:
		oops("%s: major botch.", "eval");
		break;
	}
}

char *dumpfmt = "`%s'\t`%s'\n";	       /* format string for dumpdef   */

/*
 * expand - user-defined macro expansion
 */
void
expand(argv, argc)
register char *argv[];
register int argc;
{
	register unsigned char *t;
	register unsigned char *p;
	register int n;
	register int argno;

	t = argv[0];		       /* defn string as a whole */
	p = t;
	while (*p)
		p++;
	p--;			       /* last character of defn */
	while (p > t) {
		if (*(p - 1) != ARGFLAG)
			putback(*p);
		else {
			switch (*p) {

			case '#':
				pbnum(argc - 2);
				break;
			case '0':
			case '1':
			case '2':
			case '3':
			case '4':
			case '5':
			case '6':
			case '7':
			case '8':
			case '9':
				if ((argno = *p - '0') < argc - 1)
					pbstr(argv[argno + 1]);
				break;
			case '*':
				for (n = argc - 1; n > 2; n--) {
					pbstr(argv[n]);
					putback(',');
				}
				pbstr(argv[2]);
				break;
			default:
				putback(*p);
				putback('$');
				break;
			}
			p--;
		}
		p--;
	}
	if (p == t)		       /* do last character */
		putback(*p);
}

/*
 * dodefine - install definition in the table
 */
void
dodefine(name, defn)
register char *name;
register char *defn;
{
	register ndptr p;

	if (!*name)
		oops("null definition.");
	if (STREQ(name, defn))
		oops("%s: recursive definition.", name);
	if ((p = lookup(name)) == nil)
		p = addent(name);
	else if (p->defn != null)
		free((char *) p->defn);
	if (!*defn)
		p->defn = null;
	else
		p->defn = xstrdup(defn);
	p->type = MACRTYPE;
}

/*
 * dodefn - push back a quoted definition of
 *      the given name.
 */
void
dodefn(name)
char *name;
{
	register ndptr p;

	if ((p = lookup(name)) != nil && p->defn != null) {
		putback(rquote);
		pbstr(p->defn);
		putback(lquote);
	}
}

/*
 * dopushdef - install a definition in the hash table
 *      without removing a previous definition. Since
 *      each new entry is entered in *front* of the
 *      hash bucket, it hides a previous definition from
 *      lookup.
 */
void
dopushdef(name, defn)
register char *name;
register char *defn;
{
	register ndptr p;

	if (!*name)
		oops("null definition");
	if (STREQ(name, defn))
		oops("%s: recursive definition.", name);
	p = addent(name);
	if (!*defn)
		p->defn = null;
	else
		p->defn = xstrdup(defn);
	p->type = MACRTYPE;
}

/*
 * dodumpdef - dump the specified definitions in the hash
 *      table to stderr. If nothing is specified, the entire
 *      hash table is dumped.
 */
void
dodump(argv, argc)
register char *argv[];
register int argc;
{
	register int n;
	ndptr p;

	if (argc > 2) {
		for (n = 2; n < argc; n++)
			if ((p = lookup(argv[n])) != nil)
				fprintf(stderr, dumpfmt, p->name,
					p->defn);
	}
	else {
		for (n = 0; n < HASHSIZE; n++)
			for (p = hashtab[n]; p != nil; p = p->nxtptr)
				fprintf(stderr, dumpfmt, p->name,
					p->defn);
	}
}

/*
 * doifelse - select one of two alternatives - loop.
 */
void
doifelse(argv, argc)
register char *argv[];
register int argc;
{
	cycle {
		if (STREQ(argv[2], argv[3]))
			pbstr(argv[4]);
		else if (argc == 6)
			pbstr(argv[5]);
		else if (argc > 6) {
			argv += 3;
			argc -= 3;
			continue;
		}
		break;
	}
}

/*
 * doinclude - include a given file.
 */
int
doincl(ifile)
char *ifile;
{
	if (ilevel + 1 == MAXINP)
		oops("too many include files.");
	if ((infile[ilevel + 1] = fopen(ifile, "r")) != NULL) {
		ilevel++;
		bbase[ilevel] = bufbase = bp;
		return (1);
	}
	else
		return (0);
}

#ifdef EXTENDED
/*
 * dopaste - include a given file without any
 *           macro processing.
 */
int
dopaste(pfile)
char *pfile;
{
	FILE *pf;
	register int c;

	if ((pf = fopen(pfile, "r")) != NULL) {
		while ((c = getc(pf)) != EOF)
			putc(c, active);
		(void) fclose(pf);
		return (1);
	}
	else
		return (0);
}
#endif

/*
 * dochq - change quote characters
 */
void
dochq(argv, argc)
register char *argv[];
register int argc;
{
	if (argc > 2) {
		if (*argv[2])
			lquote = *argv[2];
		if (argc > 3) {
			if (*argv[3])
				rquote = *argv[3];
		}
		else
			rquote = lquote;
	}
	else {
		lquote = LQUOTE;
		rquote = RQUOTE;
	}
}

/*
 * dochc - change comment characters
 */
void
dochc(argv, argc)
register char *argv[];
register int argc;
{
	if (argc > 2) {
		if (*argv[2])
			scommt = *argv[2];
		if (argc > 3) {
			if (*argv[3])
				ecommt = *argv[3];
		}
		else
			ecommt = ECOMMT;
	}
	else {
		scommt = SCOMMT;
		ecommt = ECOMMT;
	}
}

/*
 * dodivert - divert the output to a temporary file
 */
void
dodiv(n)
register int n;
{
	if (n < 0 || n >= MAXOUT)
		n = 0;		       /* bitbucket */
	if (outfile[n] == NULL) {
		m4temp[UNIQUE] = n + '0';
		if ((outfile[n] = fopen(m4temp, "w")) == NULL)
			oops("%s: cannot divert.", m4temp);
	}
	oindex = n;
	active = outfile[n];
}

/*
 * doundivert - undivert a specified output, or all
 *              other outputs, in numerical order.
 */
void
doundiv(argv, argc)
register char *argv[];
register int argc;
{
	register int ind;
	register int n;

	if (argc > 2) {
		for (ind = 2; ind < argc; ind++) {
			n = atoi(argv[ind]);
			if (n > 0 && n < MAXOUT && outfile[n] != NULL)
				getdiv(n);

		}
	}
	else
		for (n = 1; n < MAXOUT; n++)
			if (outfile[n] != NULL)
				getdiv(n);
}

/*
 * dosub - select substring
 */
void
dosub(argv, argc)
register char *argv[];
register int argc;
{
	register unsigned char *ap, *fc, *k;
	register int nc;

	if (argc < 5)
		nc = MAXTOK;
	else
#ifdef EXPR
		nc = expr(argv[4]);
#else
		nc = atoi(argv[4]);
#endif
	ap = argv[2];		       /* target string */
#ifdef EXPR
	fc = ap + expr(argv[3]);       /* first char */
#else
	fc = ap + atoi(argv[3]);       /* first char */
#endif
	if (fc >= ap && fc < ap + strlen(ap))
		for (k = fc + min(nc, strlen(fc)) - 1; k >= fc; k--)
			putback(*k);
}

/*
 * map:
 * map every character of s1 that is specified in from
 * into s3 and replace in s. (source s1 remains untouched)
 *
 * This is a standard implementation of map(s,from,to) function of ICON
 * language. Within mapvec, we replace every character of "from" with
 * the corresponding character in "to". If "to" is shorter than "from",
 * than the corresponding entries are null, which means that those
 * characters dissapear altogether. Furthermore, imagine
 * map(dest, "sourcestring", "srtin", "rn..*") type call. In this case,
 * `s' maps to `r', `r' maps to `n' and `n' maps to `*'. Thus, `s'
 * ultimately maps to `*'. In order to achieve this effect in an efficient
 * manner (i.e. without multiple passes over the destination string), we
 * loop over mapvec, starting with the initial source character. if the
 * character value (dch) in this location is different than the source
 * character (sch), sch becomes dch, once again to index into mapvec, until
 * the character value stabilizes (i.e. sch = dch, in other words
 * mapvec[n] == n). Even if the entry in the mapvec is null for an ordinary
 * character, it will stabilize, since mapvec[0] == 0 at all times. At the
 * end, we restore mapvec* back to normal where mapvec[n] == n for
 * 0 <= n <= 127. This strategy, along with the restoration of mapvec, is
 * about 5 times faster than any algorithm that makes multiple passes over
 * destination string.
 */
void
map(dest, src, from, to)
register char *dest;
register char *src;
register char *from;
register char *to;
{
	register char *tmp;
	register char sch, dch;
	static char mapvec[128] = {
		0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
		12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
		24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
		36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
		48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
		60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,
		72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83,
		84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
		96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,
		108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,
		120, 121, 122, 123, 124, 125, 126, 127
	};

	if (*src) {
		tmp = from;
	/*
	 * create a mapping between "from" and
	 * "to"
	 */
		while (*from)
			mapvec[*from++] = (*to) ? *to++ : (char) 0;

		while (*src) {
			sch = *src++;
			dch = mapvec[sch];
			while (dch != sch) {
				sch = dch;
				dch = mapvec[sch];
			}
			if (*dest = dch)
				dest++;
		}
	/*
	 * restore all the changed characters
	 */
		while (*tmp) {
			mapvec[*tmp] = *tmp;
			tmp++;
		}
	}
	*dest = (char) 0;
}
OpenPOWER on IntegriCloud