summaryrefslogtreecommitdiff
path: root/usr.bin/awk/lib.c
blob: 7028ea3538ad54e273bdf84bdf37400dcd97f9db (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
/*	$OpenBSD: lib.c,v 1.13 2003/04/28 03:07:40 tedu Exp $	*/
/****************************************************************
Copyright (C) Lucent Technologies 1997
All Rights Reserved

Permission to use, copy, modify, and distribute this software and
its documentation for any purpose and without fee is hereby
granted, provided that the above copyright notice appear in all
copies and that both that the copyright notice and this
permission notice and warranty disclaimer appear in supporting
documentation, and that the name Lucent Technologies or any of
its entities not be used in advertising or publicity pertaining
to distribution of the software without specific, written prior
permission.

LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
THIS SOFTWARE.
****************************************************************/

#define DEBUG
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdarg.h>
#include "awk.h"
#include "ytab.h"

FILE	*infile	= NULL;
char	*file	= "";
char	*record;
int	recsize	= RECSIZE;
char	*fields;
int	fieldssize = RECSIZE;

Cell	**fldtab;	/* pointers to Cells */
char	inputFS[100] = " ";

#define	MAXFLD	200
int	nfields	= MAXFLD;	/* last allocated slot for $i */

int	donefld;	/* 1 = implies rec broken into fields */
int	donerec;	/* 1 = record is valid (no flds have changed) */

int	lastfld	= 0;	/* last used field */
int	argno	= 1;	/* current input argument number */
extern	Awkfloat *ARGC;

static Cell dollar0 = { OCELL, CFLD, NULL, "", 0.0, REC|STR|DONTFREE };
static Cell dollar1 = { OCELL, CFLD, NULL, "", 0.0, FLD|STR|DONTFREE };

void recinit(unsigned int n)
{
	record = (char *) malloc(n);
	fields = (char *) malloc(n);
	fldtab = (Cell **) malloc((nfields+1) * sizeof(Cell *));
	if (record == NULL || fields == NULL || fldtab == NULL)
		FATAL("out of space for $0 and fields");

	fldtab[0] = (Cell *) malloc(sizeof (Cell));
	if (fldtab[0] == NULL)
		FATAL("out of space for fields");
	*fldtab[0] = dollar0;
	fldtab[0]->sval = record;
	fldtab[0]->nval = tostring("0");
	makefields(1, nfields);
}

void makefields(int n1, int n2)		/* create $n1..$n2 inclusive */
{
	char temp[50];
	int i;

	for (i = n1; i <= n2; i++) {
		fldtab[i] = (Cell *) malloc(sizeof (struct Cell));
		if (fldtab[i] == NULL)
			FATAL("out of space in makefields %d", i);
		*fldtab[i] = dollar1;
		snprintf(temp, sizeof temp, "%d", i);
		fldtab[i]->nval = tostring(temp);
	}
}

void initgetrec(void)
{
	int i;
	char *p;

	for (i = 1; i < *ARGC; i++) {
		if (!isclvar(p = getargv(i))) {	/* find 1st real filename */
			setsval(lookup("FILENAME", symtab), getargv(i));
			return;
		}
		setclvar(p);	/* a commandline assignment before filename */
		argno++;
	}
	infile = stdin;		/* no filenames, so use stdin */
}

int getrec(char **pbuf, int *pbufsize, int isrecord)	/* get next input record */
{			/* note: cares whether buf == record */
	int c;
	static int firsttime = 1;
	char *buf = *pbuf;
	int bufsize = *pbufsize;

	if (firsttime) {
		firsttime = 0;
		initgetrec();
	}
	   dprintf( ("RS=<%s>, FS=<%s>, ARGC=%g, FILENAME=%s\n",
		*RS, *FS, *ARGC, *FILENAME) );
	if (isrecord) {
		donefld = 0;
		donerec = 1;
	}
	buf[0] = 0;
	while (argno < *ARGC || infile == stdin) {
		   dprintf( ("argno=%d, file=|%s|\n", argno, file) );
		if (infile == NULL) {	/* have to open a new file */
			file = getargv(argno);
			if (*file == '\0') {	/* it's been zapped */
				argno++;
				continue;
			}
			if (isclvar(file)) {	/* a var=value arg */
				setclvar(file);
				argno++;
				continue;
			}
			*FILENAME = file;
			   dprintf( ("opening file %s\n", file) );
			if (*file == '-' && *(file+1) == '\0')
				infile = stdin;
			else if ((infile = fopen(file, "r")) == NULL)
				FATAL("can't open file %s", file);
			setfval(fnrloc, 0.0);
		}
		c = readrec(&buf, &bufsize, infile);
		if (c != 0 || buf[0] != '\0') {	/* normal record */
			if (isrecord) {
				if (freeable(fldtab[0]))
					xfree(fldtab[0]->sval);
				fldtab[0]->sval = buf;	/* buf == record */
				fldtab[0]->tval = REC | STR | DONTFREE;
				if (is_number(fldtab[0]->sval)) {
					fldtab[0]->fval = atof(fldtab[0]->sval);
					fldtab[0]->tval |= NUM;
				}
			}
			setfval(nrloc, nrloc->fval+1);
			setfval(fnrloc, fnrloc->fval+1);
			*pbuf = buf;
			*pbufsize = bufsize;
			return 1;
		}
		/* EOF arrived on this file; set up next */
		if (infile != stdin)
			fclose(infile);
		infile = NULL;
		argno++;
	}
	*pbuf = buf;
	*pbufsize = bufsize;
	return 0;	/* true end of file */
}

void nextfile(void)
{
	if (infile != stdin)
		fclose(infile);
	infile = NULL;
	argno++;
}

int readrec(char **pbuf, int *pbufsize, FILE *inf)	/* read one record into buf */
{
	int sep, c;
	char *rr, *buf = *pbuf;
	int bufsize = *pbufsize;

	if (strlen(*FS) >= sizeof(inputFS))
		FATAL("field separator %.10s... is too long", *FS);
	strlcpy(inputFS, *FS, sizeof inputFS);	/* for subsequent field splitting */
	if ((sep = **RS) == 0) {
		sep = '\n';
		while ((c=getc(inf)) == '\n' && c != EOF)	/* skip leading \n's */
			;
		if (c != EOF)
			ungetc(c, inf);
	}
	for (rr = buf; ; ) {
		for (; (c=getc(inf)) != sep && c != EOF; ) {
			if (rr-buf+1 > bufsize)
				if (!adjbuf(&buf, &bufsize, 1+rr-buf, recsize, &rr, "readrec 1"))
					FATAL("input record `%.30s...' too long", buf);
			*rr++ = c;
		}
		if (**RS == sep || c == EOF)
			break;
		if ((c = getc(inf)) == '\n' || c == EOF) /* 2 in a row */
			break;
		if (!adjbuf(&buf, &bufsize, 2+rr-buf, recsize, &rr, "readrec 2"))
			FATAL("input record `%.30s...' too long", buf);
		*rr++ = '\n';
		*rr++ = c;
	}
	if (!adjbuf(&buf, &bufsize, 1+rr-buf, recsize, &rr, "readrec 3"))
		FATAL("input record `%.30s...' too long", buf);
	*rr = 0;
	   dprintf( ("readrec saw <%s>, returns %d\n", buf, c == EOF && rr == buf ? 0 : 1) );
	*pbuf = buf;
	*pbufsize = bufsize;
	return c == EOF && rr == buf ? 0 : 1;
}

char *getargv(int n)	/* get ARGV[n] */
{
	Cell *x;
	char *s, temp[50];
	extern Array *ARGVtab;

	snprintf(temp, sizeof temp, "%d", n);
	x = setsymtab(temp, "", 0.0, STR, ARGVtab);
	s = getsval(x);
	   dprintf( ("getargv(%d) returns |%s|\n", n, s) );
	return s;
}

void setclvar(char *s)	/* set var=value from s */
{
	char *p;
	Cell *q;

	for (p=s; *p != '='; p++)
		;
	*p++ = 0;
	p = qstring(p, '\0');
	q = setsymtab(s, p, 0.0, STR, symtab);
	setsval(q, p);
	if (is_number(q->sval)) {
		q->fval = atof(q->sval);
		q->tval |= NUM;
	}
	   dprintf( ("command line set %s to |%s|\n", s, p) );
}


void fldbld(void)	/* create fields from current record */
{
	/* this relies on having fields[] the same length as $0 */
	/* the fields are all stored in this one array with \0's */
	char *r, *fr, sep;
	Cell *p;
	int i, j, n;

	if (donefld)
		return;
	if (!isstr(fldtab[0]))
		getsval(fldtab[0]);
	r = fldtab[0]->sval;
	n = strlen(r);
	if (n > fieldssize) {
		xfree(fields);
		if ((fields = (char *) malloc(n+1)) == NULL)
			FATAL("out of space for fields in fldbld %d", n);
		fieldssize = n;
	}
	fr = fields;
	i = 0;	/* number of fields accumulated here */
	if (strlen(inputFS) > 1) {	/* it's a regular expression */
		i = refldbld(r, inputFS);
	} else if ((sep = *inputFS) == ' ') {	/* default whitespace */
		for (i = 0; ; ) {
			while (*r == ' ' || *r == '\t' || *r == '\n')
				r++;
			if (*r == 0)
				break;
			i++;
			if (i > nfields)
				growfldtab(i);
			if (freeable(fldtab[i]))
				xfree(fldtab[i]->sval);
			fldtab[i]->sval = fr;
			fldtab[i]->tval = FLD | STR | DONTFREE;
			do
				*fr++ = *r++;
			while (*r != ' ' && *r != '\t' && *r != '\n' && *r != '\0');
			*fr++ = 0;
		}
		*fr = 0;
	} else if ((sep = *inputFS) == 0) {		/* new: FS="" => 1 char/field */
		for (i = 0; *r != 0; r++) {
			char buf[2];
			i++;
			if (i > nfields)
				growfldtab(i);
			if (freeable(fldtab[i]))
				xfree(fldtab[i]->sval);
			buf[0] = *r;
			buf[1] = 0;
			fldtab[i]->sval = tostring(buf);
			fldtab[i]->tval = FLD | STR;
		}
		*fr = 0;
	} else if (*r != 0) {	/* if 0, it's a null field */
		for (;;) {
			i++;
			if (i > nfields)
				growfldtab(i);
			if (freeable(fldtab[i]))
				xfree(fldtab[i]->sval);
			fldtab[i]->sval = fr;
			fldtab[i]->tval = FLD | STR | DONTFREE;
			while (*r != sep && *r != '\n' && *r != '\0')	/* \n is always a separator */
				*fr++ = *r++;
			*fr++ = 0;
			if (*r++ == 0)
				break;
		}
		*fr = 0;
	}
	if (i > nfields)
		FATAL("record `%.30s...' has too many fields; can't happen", r);
	cleanfld(i+1, lastfld);	/* clean out junk from previous record */
	lastfld = i;
	donefld = 1;
	for (j = 1; j <= lastfld; j++) {
		p = fldtab[j];
		if(is_number(p->sval)) {
			p->fval = atof(p->sval);
			p->tval |= NUM;
		}
	}
	setfval(nfloc, (Awkfloat) lastfld);
	if (dbg) {
		for (j = 0; j <= lastfld; j++) {
			p = fldtab[j];
			printf("field %d (%s): |%s|\n", j, p->nval, p->sval);
		}
	}
}

void cleanfld(int n1, int n2)	/* clean out fields n1 .. n2 inclusive */
{				/* nvals remain intact */
	Cell *p;
	int i;

	for (i = n1; i <= n2; i++) {
		p = fldtab[i];
		if (freeable(p))
			xfree(p->sval);
		p->sval = "";
		p->tval = FLD | STR | DONTFREE;
	}
}

void newfld(int n)	/* add field n after end of existing lastfld */
{
	if (n > nfields)
		growfldtab(n);
	cleanfld(lastfld+1, n);
	lastfld = n;
	setfval(nfloc, (Awkfloat) n);
}

Cell *fieldadr(int n)	/* get nth field */
{
	if (n < 0)
		FATAL("trying to access field %d", n);
	if (n > nfields)	/* fields after NF are empty */
		growfldtab(n);	/* but does not increase NF */
	return(fldtab[n]);
}

void growfldtab(int n)	/* make new fields up to at least $n */
{
	int nf = 2 * nfields;

	if (n > nf)
		nf = n;
	fldtab = (Cell **) realloc(fldtab, (nf+1) * (sizeof (struct Cell *)));
	if (fldtab == NULL)
		FATAL("out of space creating %d fields", nf);
	makefields(nfields+1, nf);
	nfields = nf;
}

int refldbld(const char *rec, const char *fs)	/* build fields from reg expr in FS */
{
	/* this relies on having fields[] the same length as $0 */
	/* the fields are all stored in this one array with \0's */
	char *fr;
	int i, tempstat, n;
	fa *pfa;

	n = strlen(rec);
	if (n > fieldssize) {
		xfree(fields);
		if ((fields = (char *) malloc(n+1)) == NULL)
			FATAL("out of space for fields in refldbld %d", n);
		fieldssize = n;
	}
	fr = fields;
	*fr = '\0';
	if (*rec == '\0')
		return 0;
	pfa = makedfa(fs, 1);
	   dprintf( ("into refldbld, rec = <%s>, pat = <%s>\n", rec, fs) );
	tempstat = pfa->initstat;
	for (i = 1; ; i++) {
		if (i > nfields)
			growfldtab(i);
		if (freeable(fldtab[i]))
			xfree(fldtab[i]->sval);
		fldtab[i]->tval = FLD | STR | DONTFREE;
		fldtab[i]->sval = fr;
		   dprintf( ("refldbld: i=%d\n", i) );
		if (nematch(pfa, rec)) {
			pfa->initstat = 2;	/* horrible coupling to b.c */
			   dprintf( ("match %s (%d chars)\n", patbeg, patlen) );
			strncpy(fr, rec, patbeg-rec);
			fr += patbeg - rec + 1;
			*(fr-1) = '\0';
			rec = patbeg + patlen;
		} else {
			   dprintf( ("no match %s\n", rec) );
			strlcpy(fr, rec, fields + fieldssize - fr);
			pfa->initstat = tempstat;
			break;
		}
	}
	return i;		
}

void recbld(void)	/* create $0 from $1..$NF if necessary */
{
	int i;
	char *r, *p;

	if (donerec == 1)
		return;
	r = record;
	for (i = 1; i <= *NF; i++) {
		p = getsval(fldtab[i]);
		if (!adjbuf(&record, &recsize, 1+strlen(p)+r-record, recsize, &r, "recbld 1"))
			FATAL("created $0 `%.30s...' too long", record);
		while ((*r = *p++) != 0)
			r++;
		if (i < *NF) {
			if (!adjbuf(&record, &recsize, 2+strlen(*OFS)+r-record, recsize, &r, "recbld 2"))
				FATAL("created $0 `%.30s...' too long", record);
			for (p = *OFS; (*r = *p++) != 0; )
				r++;
		}
	}
	if (!adjbuf(&record, &recsize, 2+r-record, recsize, &r, "recbld 3"))
		FATAL("built giant record `%.30s...'", record);
	*r = '\0';
	   dprintf( ("in recbld inputFS=%s, fldtab[0]=%p\n", inputFS, fldtab[0]) );

	if (freeable(fldtab[0]))
		xfree(fldtab[0]->sval);
	fldtab[0]->tval = REC | STR | DONTFREE;
	fldtab[0]->sval = record;

	   dprintf( ("in recbld inputFS=%s, fldtab[0]=%p\n", inputFS, fldtab[0]) );
	   dprintf( ("recbld = |%s|\n", record) );
	donerec = 1;
}

int	errorflag	= 0;

void yyerror(const char *s)
{
	SYNTAX(s);
}

void SYNTAX(const char *fmt, ...)
{
	extern char *cmdname, *curfname;
	static int been_here = 0;
	va_list varg;

	if (been_here++ > 2)
		return;
	fprintf(stderr, "%s: ", cmdname);
	va_start(varg, fmt);
	vfprintf(stderr, fmt, varg);
	va_end(varg);
	fprintf(stderr, " at source line %d", lineno);
	if (curfname != NULL)
		fprintf(stderr, " in function %s", curfname);
	if (compile_time == 1 && cursource() != NULL)
		fprintf(stderr, " source file %s", cursource());
	fprintf(stderr, "\n");
	errorflag = 2;
	eprint();
}

void fpecatch(int sig)
{
	extern Node *curnode;
	char buf[1024];

	snprintf(buf, sizeof buf, "floating point exception\n");
	write(STDERR_FILENO, buf, strlen(buf));

	if (compile_time != 2 && NR && *NR > 0) {
		snprintf(buf, sizeof buf, " input record number %d", (int) (*FNR));
		write(STDERR_FILENO, buf, strlen(buf));

		if (strcmp(*FILENAME, "-") != 0) {
			snprintf(buf, sizeof buf, ", file %s", *FILENAME);
			write(STDERR_FILENO, buf, strlen(buf));
		}
		write(STDERR_FILENO, "\n", 1);
	}
	if (compile_time != 2 && curnode) {
		snprintf(buf, sizeof buf, " source line number %d", curnode->lineno);
		write(STDERR_FILENO, buf, strlen(buf));
	} else if (compile_time != 2 && lineno) {
		snprintf(buf, sizeof buf, " source line number %d", lineno);
		write(STDERR_FILENO, buf, strlen(buf));
	}
	if (compile_time == 1 && cursource() != NULL) {
		snprintf(buf, sizeof buf, " source file %s", cursource());
		write(STDERR_FILENO, buf, strlen(buf));
	}
	write(STDERR_FILENO, "\n", 1);
	if (dbg > 1)		/* core dump if serious debugging on */
		abort();
	_exit(1);
}

extern int bracecnt, brackcnt, parencnt;

void bracecheck(void)
{
	int c;
	static int beenhere = 0;

	if (beenhere++)
		return;
	while ((c = input()) != EOF && c != '\0')
		bclass(c);
	bcheck2(bracecnt, '{', '}');
	bcheck2(brackcnt, '[', ']');
	bcheck2(parencnt, '(', ')');
}

void bcheck2(int n, int c1, int c2)
{
	if (n == 1)
		fprintf(stderr, "\tmissing %c\n", c2);
	else if (n > 1)
		fprintf(stderr, "\t%d missing %c's\n", n, c2);
	else if (n == -1)
		fprintf(stderr, "\textra %c\n", c2);
	else if (n < -1)
		fprintf(stderr, "\t%d extra %c's\n", -n, c2);
}

void FATAL(const char *fmt, ...)
{
	extern char *cmdname;
	va_list varg;

	fflush(stdout);
	fprintf(stderr, "%s: ", cmdname);
	va_start(varg, fmt);
	vfprintf(stderr, fmt, varg);
	va_end(varg);
	error();
	if (dbg > 1)		/* core dump if serious debugging on */
		abort();
	exit(2);
}

void WARNING(const char *fmt, ...)
{
	extern char *cmdname;
	va_list varg;

	fflush(stdout);
	fprintf(stderr, "%s: ", cmdname);
	va_start(varg, fmt);
	vfprintf(stderr, fmt, varg);
	va_end(varg);
	error();
}

void error()
{
	extern Node *curnode;

	fprintf(stderr, "\n");
	if (compile_time != 2 && NR && *NR > 0) {
		fprintf(stderr, " input record number %d", (int) (*FNR));
		if (strcmp(*FILENAME, "-") != 0)
			fprintf(stderr, ", file %s", *FILENAME);
		fprintf(stderr, "\n");
	}
	if (compile_time != 2 && curnode)
		fprintf(stderr, " source line number %d", curnode->lineno);
	else if (compile_time != 2 && lineno)
		fprintf(stderr, " source line number %d", lineno);
	if (compile_time == 1 && cursource() != NULL)
		fprintf(stderr, " source file %s", cursource());
	fprintf(stderr, "\n");
	eprint();
}

void eprint(void)	/* try to print context around error */
{
	char *p, *q;
	int c;
	static int been_here = 0;
	extern char ebuf[], *ep;

	if (compile_time == 2 || compile_time == 0 || been_here++ > 0)
		return;
	p = ep - 1;
	if (p > ebuf && *p == '\n')
		p--;
	for ( ; p > ebuf && *p != '\n' && *p != '\0'; p--)
		;
	while (*p == '\n')
		p++;
	fprintf(stderr, " context is\n\t");
	for (q=ep-1; q>=p && *q!=' ' && *q!='\t' && *q!='\n'; q--)
		;
	for ( ; p < q; p++)
		if (*p)
			putc(*p, stderr);
	fprintf(stderr, " >>> ");
	for ( ; p < ep; p++)
		if (*p)
			putc(*p, stderr);
	fprintf(stderr, " <<< ");
	if (*ep)
		while ((c = input()) != '\n' && c != '\0' && c != EOF) {
			putc(c, stderr);
			bclass(c);
		}
	putc('\n', stderr);
	ep = ebuf;
}

void bclass(int c)
{
	switch (c) {
	case '{': bracecnt++; break;
	case '}': bracecnt--; break;
	case '[': brackcnt++; break;
	case ']': brackcnt--; break;
	case '(': parencnt++; break;
	case ')': parencnt--; break;
	}
}

double errcheck(double x, const char *s)
{

	if (errno == EDOM) {
		errno = 0;
		WARNING("%s argument out of domain", s);
		x = 1;
	} else if (errno == ERANGE) {
		errno = 0;
		WARNING("%s result out of range", s);
		x = 1;
	}
	return x;
}

int isclvar(const char *s)	/* is s of form var=something ? */
{
	const char *os = s;

	if (!isalpha((uschar) *s) && *s != '_')
		return 0;
	for ( ; *s; s++)
		if (!(isalnum((uschar) *s) || *s == '_'))
			break;
	return *s == '=' && s > os && *(s+1) != '=';
}

/* strtod is supposed to be a proper test of what's a valid number */
/* appears to be broken in gcc on linux: thinks 0x123 is a valid FP number */
/* wrong: violates 4.10.1.4 of ansi C standard */

#include <math.h>
int is_number(const char *s)
{
	double r;
	char *ep;
	errno = 0;
	r = strtod(s, &ep);
	if (ep == s || r == HUGE_VAL || errno == ERANGE)
		return 0;
	while (*ep == ' ' || *ep == '\t' || *ep == '\n')
		ep++;
	if (*ep == '\0')
		return 1;
	else
		return 0;
}