xref: /illumos-gate/usr/src/cmd/awk/run.c (revision b12258b69ac245658b0ca5ae070b3ff004186148)
1 /*
2  * Copyright (C) Lucent Technologies 1997
3  * All Rights Reserved
4  *
5  * Permission to use, copy, modify, and distribute this software and
6  * its documentation for any purpose and without fee is hereby
7  * granted, provided that the above copyright notice appear in all
8  * copies and that both that the copyright notice and this
9  * permission notice and warranty disclaimer appear in supporting
10  * documentation, and that the name Lucent Technologies or any of
11  * its entities not be used in advertising or publicity pertaining
12  * to distribution of the software without specific, written prior
13  * permission.
14  *
15  * LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
16  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
17  * IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
18  * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
20  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
21  * ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
22  * THIS SOFTWARE.
23  */
24 
25 /*
26  * CDDL HEADER START
27  *
28  * The contents of this file are subject to the terms of the
29  * Common Development and Distribution License (the "License").
30  * You may not use this file except in compliance with the License.
31  *
32  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
33  * or http://www.opensolaris.org/os/licensing.
34  * See the License for the specific language governing permissions
35  * and limitations under the License.
36  *
37  * When distributing Covered Code, include this CDDL HEADER in each
38  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
39  * If applicable, add the following below this CDDL HEADER, with the
40  * fields enclosed by brackets "[]" replaced with your own identifying
41  * information: Portions Copyright [yyyy] [name of copyright owner]
42  *
43  * CDDL HEADER END
44  */
45 
46 /*
47  * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
48  */
49 
50 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
51 /*	  All Rights Reserved  	*/
52 
53 #define	DEBUG
54 #include	<stdio.h>
55 #include	<ctype.h>
56 #include	<setjmp.h>
57 #include	<math.h>
58 #include	<time.h>
59 #include	<sys/wait.h>
60 #include	"awk.h"
61 #include	"y.tab.h"
62 
63 #define	tempfree(x)	if (istemp(x)) tfree(x)
64 
65 static jmp_buf env;
66 extern	Awkfloat	srand_seed;
67 
68 static	Cell	*execute(Node *);
69 static	Cell	*gettemp(void), *copycell(Cell *);
70 static	FILE	*openfile(int, const char *), *redirect(int, Node *);
71 
72 Node	*winner = NULL;		/* root of parse tree */
73 static Cell	*tmps;		/* free temporary cells for execution */
74 
75 static Cell	truecell	= { OBOOL, BTRUE, NULL, NULL, 1.0, NUM, NULL };
76 Cell	*True	= &truecell;
77 static Cell	falsecell	= { OBOOL, BFALSE, NULL, NULL, 0.0, NUM, NULL };
78 Cell	*False	= &falsecell;
79 static Cell	breakcell	= { OJUMP, JBREAK, NULL, NULL, 0.0, NUM, NULL };
80 Cell	*jbreak	= &breakcell;
81 static Cell	contcell	= { OJUMP, JCONT, NULL, NULL, 0.0, NUM, NULL };
82 Cell	*jcont	= &contcell;
83 static Cell	nextcell	= { OJUMP, JNEXT, NULL, NULL, 0.0, NUM, NULL };
84 Cell	*jnext	= &nextcell;
85 static Cell	nextfilecell	= { OJUMP, JNEXTFILE, NULL, NULL, 0.0,
86 				    NUM, NULL };
87 Cell	*jnextfile	= &nextfilecell;
88 static Cell	exitcell	= { OJUMP, JEXIT, NULL, NULL, 0.0, NUM, NULL };
89 Cell	*jexit	= &exitcell;
90 static Cell	retcell		= { OJUMP, JRET, NULL, NULL, 0.0, NUM, NULL };
91 Cell	*jret	= &retcell;
92 static Cell	tempcell	= { OCELL, CTEMP, NULL, "", 0.0,
93 				    NUM|STR|DONTFREE, NULL };
94 
95 Node	*curnode = NULL;	/* the node being executed, for debugging */
96 
97 static	void	tfree(Cell *);
98 static	void	closeall(void);
99 static	double	ipow(double, int);
100 static	void	backsub(char **pb_ptr, char **sptr_ptr);
101 
102 
103 /*
104  * buffer memory management
105  *
106  * pbuf:    address of pointer to buffer being managed
107  * psiz:    address of buffer size variable
108  * minlen:  minimum length of buffer needed
109  * quantum: buffer size quantum
110  * pbptr:   address of movable pointer into buffer, or 0 if none
111  * whatrtn: name of the calling routine if failure should cause fatal error
112  *
113  * return   0 for realloc failure, !=0 for success
114  */
115 int
116 adjbuf(char **pbuf, size_t *psiz, size_t minlen, size_t quantum, char **pbptr,
117     const char *whatrtn)
118 {
119 	if (minlen > *psiz) {
120 		char *tbuf;
121 		int rminlen = quantum ? minlen % quantum : 0;
122 		int boff = pbptr ? *pbptr - *pbuf : 0;
123 		/* round up to next multiple of quantum */
124 		if (rminlen)
125 			minlen += quantum - rminlen;
126 		tbuf = (char *)realloc(*pbuf, minlen);
127 		dprintf(("adjbuf %s: %d %d (pbuf=%p, tbuf=%p)\n", whatrtn,
128 		    *psiz, minlen, (void *)*pbuf, (void *)tbuf));
129 		if (tbuf == NULL) {
130 			if (whatrtn)
131 				FATAL("out of memory in %s", whatrtn);
132 			return (0);
133 		}
134 		*pbuf = tbuf;
135 		*psiz = minlen;
136 		if (pbptr)
137 			*pbptr = tbuf + boff;
138 	}
139 	return (1);
140 }
141 
142 void
143 run(Node *a)	/* execution of parse tree starts here */
144 {
145 	extern void stdinit(void);
146 
147 	stdinit();
148 	(void) execute(a);
149 	closeall();
150 }
151 
152 static Cell *
153 execute(Node *u)	/* execute a node of the parse tree */
154 {
155 	Cell *(*proc)(Node **, int);
156 	Cell *x;
157 	Node *a;
158 
159 	if (u == NULL)
160 		return (True);
161 	for (a = u; ; a = a->nnext) {
162 		curnode = a;
163 		if (isvalue(a)) {
164 			x = (Cell *) (a->narg[0]);
165 			if (isfld(x) && !donefld)
166 				fldbld();
167 			else if (isrec(x) && !donerec)
168 				recbld();
169 			return (x);
170 		}
171 		/* probably a Cell* but too risky to print */
172 		if (notlegal(a->nobj))
173 			FATAL("illegal statement");
174 		proc = proctab[a->nobj-FIRSTTOKEN];
175 		x = (*proc)(a->narg, a->nobj);
176 		if (isfld(x) && !donefld)
177 			fldbld();
178 		else if (isrec(x) && !donerec)
179 			recbld();
180 		if (isexpr(a))
181 			return (x);
182 		/* a statement, goto next statement */
183 		if (isjump(x))
184 			return (x);
185 		if (a->nnext == NULL)
186 			return (x);
187 		tempfree(x);
188 	}
189 }
190 
191 /* execute an awk program */
192 /* a[0] = BEGIN, a[1] = body, a[2] = END */
193 /*ARGSUSED*/
194 Cell *
195 program(Node **a, int n)
196 {
197 	Cell *x;
198 
199 	if (setjmp(env) != 0)
200 		goto ex;
201 	if (a[0]) {		/* BEGIN */
202 		x = execute(a[0]);
203 		if (isexit(x))
204 			return (True);
205 		if (isjump(x)) {
206 			FATAL("illegal break, continue, next or nextfile "
207 			    "from BEGIN");
208 		}
209 		tempfree(x);
210 	}
211 	if (a[1] || a[2])
212 		while (getrec(&record, &recsize, 1) > 0) {
213 			x = execute(a[1]);
214 			if (isexit(x))
215 				break;
216 			tempfree(x);
217 		}
218 ex:
219 	if (setjmp(env) != 0)	/* handles exit within END */
220 		goto ex1;
221 	if (a[2]) {		/* END */
222 		x = execute(a[2]);
223 		if (isbreak(x) || isnext(x) || iscont(x))
224 			FATAL("illegal break, continue, next or nextfile "
225 			    "from END");
226 		tempfree(x);
227 	}
228 ex1:
229 	return (True);
230 }
231 
232 struct Frame {	/* stack frame for awk function calls */
233 	int nargs;	/* number of arguments in this call */
234 	Cell *fcncell;	/* pointer to Cell for function */
235 	Cell **args;	/* pointer to array of arguments after execute */
236 	Cell *retval;	/* return value */
237 };
238 
239 #define	NARGS	50	/* max args in a call */
240 
241 struct Frame *frame = NULL;	/* base of stack frames; dynamically alloc'd */
242 int	nframe = 0;		/* number of frames allocated */
243 struct Frame *fp = NULL;	/* frame pointer. bottom level unused */
244 
245 /*ARGSUSED*/
246 Cell *
247 call(Node **a, int n)	/* function call.  very kludgy and fragile */
248 {
249 	static Cell newcopycell =
250 		{ OCELL, CCOPY, 0, "", 0.0, NUM|STR|DONTFREE, NULL };
251 	int i, ncall, ndef;
252 	/* handles potential double freeing when fcn & param share a tempcell */
253 	int freed = 0;
254 	Node *x;
255 	Cell *args[NARGS], *oargs[NARGS];	/* BUG: fixed size arrays */
256 	Cell *y, *z, *fcn;
257 	char *s;
258 
259 	fcn = execute(a[0]);	/* the function itself */
260 	s = fcn->nval;
261 	if (!isfcn(fcn))
262 		FATAL("calling undefined function %s", s);
263 	if (frame == NULL) {
264 		fp = frame = (struct Frame *)calloc(nframe += 100,
265 		    sizeof (struct Frame));
266 		if (frame == NULL) {
267 			FATAL("out of space for stack frames calling %s", s);
268 		}
269 	}
270 	for (ncall = 0, x = a[1]; x != NULL; x = x->nnext) /* args in call */
271 		ncall++;
272 	ndef = (int)fcn->fval;			/* args in defn */
273 	dprintf(("calling %s, %d args (%d in defn), fp=%d\n",
274 	    s, ncall, ndef, fp-frame));
275 	if (ncall > ndef) {
276 		WARNING("function %s called with %d args, uses only %d",
277 		    s, ncall, ndef);
278 	}
279 	if (ncall + ndef > NARGS) {
280 		FATAL("function %s has %d arguments, limit %d",
281 		    s, ncall+ndef, NARGS);
282 	}
283 	for (i = 0, x = a[1]; x != NULL; i++, x = x->nnext) {
284 		/* get call args */
285 		dprintf(("evaluate args[%d], fp=%d:\n", i, fp-frame));
286 		y = execute(x);
287 		oargs[i] = y;
288 		dprintf(("args[%d]: %s %f <%s>, t=%o\n",
289 		    i, NN(y->nval), y->fval,
290 		    isarr(y) ? "(array)" : NN(y->sval), y->tval));
291 		if (isfcn(y)) {
292 			FATAL("can't use function %s as argument in %s",
293 			    y->nval, s);
294 		}
295 		if (isarr(y))
296 			args[i] = y;	/* arrays by ref */
297 		else
298 			args[i] = copycell(y);
299 		tempfree(y);
300 	}
301 	for (; i < ndef; i++) {	/* add null args for ones not provided */
302 		args[i] = gettemp();
303 		*args[i] = newcopycell;
304 	}
305 	fp++;	/* now ok to up frame */
306 	if (fp >= frame + nframe) {
307 		int dfp = fp - frame;	/* old index */
308 		frame = (struct Frame *)
309 		    realloc(frame, (nframe += 100) * sizeof (struct Frame));
310 		if (frame == NULL)
311 			FATAL("out of space for stack frames in %s", s);
312 		fp = frame + dfp;
313 	}
314 	fp->fcncell = fcn;
315 	fp->args = args;
316 	fp->nargs = ndef;	/* number defined with (excess are locals) */
317 	fp->retval = gettemp();
318 
319 	dprintf(("start exec of %s, fp=%d\n", s, fp-frame));
320 	/*LINTED align*/
321 	y = execute((Node *)(fcn->sval));	/* execute body */
322 	dprintf(("finished exec of %s, fp=%d\n", s, fp-frame));
323 
324 	for (i = 0; i < ndef; i++) {
325 		Cell *t = fp->args[i];
326 		if (isarr(t)) {
327 			if (t->csub == CCOPY) {
328 				if (i >= ncall) {
329 					freesymtab(t);
330 					t->csub = CTEMP;
331 					tempfree(t);
332 				} else {
333 					oargs[i]->tval = t->tval;
334 					oargs[i]->tval &= ~(STR|NUM|DONTFREE);
335 					oargs[i]->sval = t->sval;
336 					tempfree(t);
337 				}
338 			}
339 		} else if (t != y) {	/* kludge to prevent freeing twice */
340 			t->csub = CTEMP;
341 			tempfree(t);
342 		} else if (t == y && t->csub == CCOPY) {
343 			t->csub = CTEMP;
344 			tempfree(t);
345 			freed = 1;
346 		}
347 	}
348 	tempfree(fcn);
349 	if (isexit(y) || isnext(y))
350 		return (y);
351 	if (freed == 0) {
352 		tempfree(y);	/* don't free twice! */
353 	}
354 	z = fp->retval;			/* return value */
355 	dprintf(("%s returns %g |%s| %o\n",
356 	    s, getfval(z), getsval(z), z->tval));
357 	fp--;
358 	return (z);
359 }
360 
361 static Cell *
362 copycell(Cell *x)	/* make a copy of a cell in a temp */
363 {
364 	Cell *y;
365 
366 	/* copy is not constant or field */
367 
368 	y = gettemp();
369 	y->tval = x->tval & ~(CON|FLD|REC);
370 	y->csub = CCOPY;	/* prevents freeing until call is over */
371 	y->nval = x->nval;	/* BUG? */
372 	if (isstr(x)) {
373 		y->sval = tostring(x->sval);
374 		y->tval &= ~DONTFREE;
375 	} else
376 		y->tval |= DONTFREE;
377 	y->fval = x->fval;
378 	return (y);
379 }
380 
381 /*ARGSUSED*/
382 Cell *
383 arg(Node **a, int nnn)	/* nth argument of a function */
384 {
385 	int n;
386 
387 	n = ptoi(a[0]);	/* argument number, counting from 0 */
388 	dprintf(("arg(%d), fp->nargs=%d\n", n, fp->nargs));
389 	if (n+1 > fp->nargs) {
390 		FATAL("argument #%d of function %s was not supplied",
391 		    n+1, fp->fcncell->nval);
392 	}
393 	return (fp->args[n]);
394 }
395 
396 Cell *
397 jump(Node **a, int n)	/* break, continue, next, nextfile, return */
398 {
399 	Cell *y;
400 
401 	switch (n) {
402 	case EXIT:
403 		if (a[0] != NULL) {
404 			y = execute(a[0]);
405 			errorflag = (int)getfval(y);
406 			tempfree(y);
407 		}
408 		longjmp(env, 1);
409 		/*NOTREACHED*/
410 	case RETURN:
411 		if (a[0] != NULL) {
412 			y = execute(a[0]);
413 			if ((y->tval & (STR|NUM)) == (STR|NUM)) {
414 				(void) setsval(fp->retval, getsval(y));
415 				fp->retval->fval = getfval(y);
416 				fp->retval->tval |= NUM;
417 			} else if (y->tval & STR)
418 				(void) setsval(fp->retval, getsval(y));
419 			else if (y->tval & NUM)
420 				(void) setfval(fp->retval, getfval(y));
421 			else		/* can't happen */
422 				FATAL("bad type variable %d", y->tval);
423 			tempfree(y);
424 		}
425 		return (jret);
426 	case NEXT:
427 		return (jnext);
428 	case NEXTFILE:
429 		nextfile();
430 		return (jnextfile);
431 	case BREAK:
432 		return (jbreak);
433 	case CONTINUE:
434 		return (jcont);
435 	default:	/* can't happen */
436 		FATAL("illegal jump type %d", n);
437 	}
438 	/*NOTREACHED*/
439 	return (NULL);
440 }
441 
442 Cell *
443 awkgetline(Node **a, int n)	/* get next line from specific input */
444 {
445 	/* a[0] is variable, a[1] is operator, a[2] is filename */
446 	Cell *r, *x;
447 	FILE *fp;
448 	char *buf;
449 	size_t bufsize = recsize;
450 	int mode;
451 
452 	if ((buf = (char *)malloc(bufsize)) == NULL)
453 		FATAL("out of memory in getline");
454 
455 	(void) fflush(stdout);	/* in case someone is waiting for a prompt */
456 	r = gettemp();
457 	if (a[1] != NULL) {		/* getline < file */
458 		x = execute(a[2]);		/* filename */
459 		mode = ptoi(a[1]);
460 		if (mode == '|')	/* input pipe */
461 			mode = LE;	/* arbitrary flag */
462 		fp = openfile(mode, getsval(x));
463 		tempfree(x);
464 		if (fp == NULL)
465 			n = -1;
466 		else
467 			n = readrec(&buf, &bufsize, fp);
468 		/*LINTED if*/
469 		if (n <= 0) {
470 			;
471 		} else if (a[0] != NULL) {	/* getline var <file */
472 			x = execute(a[0]);
473 			(void) setsval(x, buf);
474 			tempfree(x);
475 		} else {			/* getline <file */
476 			(void) setsval(recloc, buf);
477 			if (is_number(recloc->sval)) {
478 				recloc->fval = atof(recloc->sval);
479 				recloc->tval |= NUM;
480 			}
481 		}
482 	} else {			/* bare getline; use current input */
483 		if (a[0] == NULL)	/* getline */
484 			n = getrec(&record, &recsize, 1);
485 		else {			/* getline var */
486 			n = getrec(&buf, &bufsize, 0);
487 			x = execute(a[0]);
488 			(void) setsval(x, buf);
489 			tempfree(x);
490 		}
491 	}
492 	(void) setfval(r, (Awkfloat)n);
493 	free(buf);
494 	return (r);
495 }
496 
497 /*ARGSUSED*/
498 Cell *
499 getnf(Node **a, int n)	/* get NF */
500 {
501 	if (donefld == 0)
502 		fldbld();
503 	return ((Cell *)a[0]);
504 }
505 
506 /*ARGSUSED*/
507 Cell *
508 array(Node **a, int n)	/* a[0] is symtab, a[1] is list of subscripts */
509 {
510 	Cell *x, *y, *z;
511 	char *s;
512 	Node *np;
513 	char *buf;
514 	size_t bufsz = recsize;
515 	size_t tlen = 0, len, nsub;
516 
517 	if ((buf = (char *)malloc(bufsz)) == NULL)
518 		FATAL("out of memory in array");
519 
520 	x = execute(a[0]);	/* Cell* for symbol table */
521 	buf[0] = '\0';
522 	for (np = a[1]; np != NULL; np = np->nnext) {
523 		y = execute(np);	/* subscript */
524 		s = getsval(y);
525 		len = strlen(s);
526 		nsub = strlen(getsval(subseploc));
527 		(void) adjbuf(&buf, &bufsz, tlen + len + nsub + 1,
528 		    recsize, 0, "array");
529 		(void) memcpy(&buf[tlen], s, len);
530 		tlen += len;
531 		if (np->nnext) {
532 			(void) memcpy(&buf[tlen], *SUBSEP, nsub);
533 			tlen += nsub;
534 		}
535 		buf[tlen] = '\0';
536 		tempfree(y);
537 	}
538 	if (!isarr(x)) {
539 		dprintf(("making %s into an array\n", NN(x->nval)));
540 		if (freeable(x))
541 			xfree(x->sval);
542 		x->tval &= ~(STR|NUM|DONTFREE);
543 		x->tval |= ARR;
544 		x->sval = (char *)makesymtab(NSYMTAB);
545 	}
546 	/*LINTED align*/
547 	z = setsymtab(buf, "", 0.0, STR|NUM, (Array *)x->sval);
548 	z->ctype = OCELL;
549 	z->csub = CVAR;
550 	tempfree(x);
551 	free(buf);
552 	return (z);
553 }
554 
555 /*ARGSUSED*/
556 Cell *
557 awkdelete(Node **a, int n)	/* a[0] is symtab, a[1] is list of subscripts */
558 {
559 	Cell *x, *y;
560 	Node *np;
561 	char *s;
562 	size_t nsub;
563 	size_t tlen = 0, len;
564 
565 	x = execute(a[0]);	/* Cell* for symbol table */
566 	if (x == symtabloc) {
567 		FATAL("cannot delete SYMTAB or its elements");
568 	}
569 	if (!isarr(x)) {
570 		dprintf(("making %s into an array\n", x->nval));
571 		if (freeable(x))
572 			xfree(x->sval);
573 		x->tval &= ~(STR|NUM|DONTFREE);
574 		x->tval |= ARR;
575 		x->sval = (char *)makesymtab(NSYMTAB);
576 	}
577 	if (a[1] == NULL) {	/* delete the elements, not the table */
578 		freesymtab(x);
579 		x->tval &= ~STR;
580 		x->tval |= ARR;
581 		x->sval = (char *)makesymtab(NSYMTAB);
582 	} else {
583 		size_t bufsz = recsize;
584 		char *buf;
585 		if ((buf = (char *)malloc(bufsz)) == NULL)
586 			FATAL("out of memory in awkdelete");
587 		buf[0] = '\0';
588 		for (np = a[1]; np != NULL; np = np->nnext) {
589 			y = execute(np);	/* subscript */
590 			s = getsval(y);
591 			len = strlen(s);
592 			nsub = strlen(getsval(subseploc));
593 			(void) adjbuf(&buf, &bufsz, tlen + len + nsub + 1,
594 			    recsize, 0, "awkdelete");
595 			(void) memcpy(&buf[tlen], s, len);
596 			tlen += len;
597 			if (np->nnext) {
598 				(void) memcpy(&buf[tlen], *SUBSEP, nsub);
599 				tlen += nsub;
600 			}
601 			buf[tlen] = '\0';
602 			tempfree(y);
603 		}
604 		freeelem(x, buf);
605 		free(buf);
606 	}
607 	tempfree(x);
608 	return (True);
609 }
610 
611 /*ARGSUSED*/
612 Cell *
613 intest(Node **a, int n)	/* a[0] is index (list), a[1] is symtab */
614 {
615 	Cell *x, *ap, *k;
616 	Node *p;
617 	char *buf;
618 	char *s;
619 	size_t bufsz = recsize;
620 	size_t nsub;
621 	size_t tlen = 0, len;
622 
623 	ap = execute(a[1]);	/* array name */
624 	if (!isarr(ap)) {
625 		dprintf(("making %s into an array\n", ap->nval));
626 		if (freeable(ap))
627 			xfree(ap->sval);
628 		ap->tval &= ~(STR|NUM|DONTFREE);
629 		ap->tval |= ARR;
630 		ap->sval = (char *)makesymtab(NSYMTAB);
631 	}
632 	if ((buf = (char *)malloc(bufsz)) == NULL) {
633 		FATAL("out of memory in intest");
634 	}
635 	buf[0] = '\0';
636 	for (p = a[0]; p != NULL; p = p->nnext) {
637 		x = execute(p);	/* expr */
638 		s = getsval(x);
639 		len = strlen(s);
640 		nsub = strlen(getsval(subseploc));
641 		(void) adjbuf(&buf, &bufsz, tlen + len + nsub + 1,
642 		    recsize, 0, "intest");
643 		(void) memcpy(&buf[tlen], s, len);
644 		tlen += len;
645 		tempfree(x);
646 		if (p->nnext) {
647 			(void) memcpy(&buf[tlen], *SUBSEP, nsub);
648 			tlen += nsub;
649 		}
650 		buf[tlen] = '\0';
651 	}
652 	/*LINTED align*/
653 	k = lookup(buf, (Array *)ap->sval);
654 	tempfree(ap);
655 	free(buf);
656 	if (k == NULL)
657 		return (False);
658 	else
659 		return (True);
660 }
661 
662 
663 Cell *
664 matchop(Node **a, int n)	/* ~ and match() */
665 {
666 	Cell *x, *y;
667 	char *s, *t;
668 	int i;
669 	fa *pfa;
670 	int (*mf)(fa *, const char *) = match, mode = 0;
671 
672 	if (n == MATCHFCN) {
673 		mf = pmatch;
674 		mode = 1;
675 	}
676 	x = execute(a[1]);	/* a[1] = target text */
677 	s = getsval(x);
678 	if (a[0] == NULL)	/* a[1] == 0: already-compiled reg expr */
679 		i = (*mf)((fa *)a[2], s);
680 	else {
681 		y = execute(a[2]);	/* a[2] = regular expr */
682 		t = getsval(y);
683 		pfa = makedfa(t, mode);
684 		i = (*mf)(pfa, s);
685 		tempfree(y);
686 	}
687 	tempfree(x);
688 	if (n == MATCHFCN) {
689 		int start = patbeg - s + 1;
690 		if (patlen < 0)
691 			start = 0;
692 		(void) setfval(rstartloc, (Awkfloat)start);
693 		(void) setfval(rlengthloc, (Awkfloat)patlen);
694 		x = gettemp();
695 		x->tval = NUM;
696 		x->fval = start;
697 		return (x);
698 	} else if ((n == MATCH && i == 1) || (n == NOTMATCH && i == 0))
699 		return (True);
700 	else
701 		return (False);
702 }
703 
704 
705 Cell *
706 boolop(Node **a, int n)	/* a[0] || a[1], a[0] && a[1], !a[0] */
707 {
708 	Cell *x, *y;
709 	int i;
710 
711 	x = execute(a[0]);
712 	i = istrue(x);
713 	tempfree(x);
714 	switch (n) {
715 	case BOR:
716 		if (i)
717 			return (True);
718 		y = execute(a[1]);
719 		i = istrue(y);
720 		tempfree(y);
721 		return (i ? True : False);
722 	case AND:
723 		if (!i)
724 			return (False);
725 		y = execute(a[1]);
726 		i = istrue(y);
727 		tempfree(y);
728 		return (i ? True : False);
729 	case NOT:
730 		return (i ? False : True);
731 	default:	/* can't happen */
732 		FATAL("unknown boolean operator %d", n);
733 	}
734 	/*NOTREACHED*/
735 	return (NULL);
736 }
737 
738 Cell *
739 relop(Node **a, int n)	/* a[0] < a[1], etc. */
740 {
741 	int i;
742 	Cell *x, *y;
743 	Awkfloat j;
744 
745 	x = execute(a[0]);
746 	y = execute(a[1]);
747 	if (x->tval&NUM && y->tval&NUM) {
748 		j = x->fval - y->fval;
749 		i = j < 0 ? -1: (j > 0 ? 1: 0);
750 	} else {
751 		i = strcmp(getsval(x), getsval(y));
752 	}
753 	tempfree(x);
754 	tempfree(y);
755 	switch (n) {
756 	case LT:	return (i < 0 ? True : False);
757 	case LE:	return (i <= 0 ? True : False);
758 	case NE:	return (i != 0 ? True : False);
759 	case EQ:	return (i == 0 ? True : False);
760 	case GE:	return (i >= 0 ? True : False);
761 	case GT:	return (i > 0 ? True : False);
762 	default:	/* can't happen */
763 		FATAL("unknown relational operator %d", n);
764 	}
765 	/*NOTREACHED*/
766 	return (False);
767 }
768 
769 static void
770 tfree(Cell *a)	/* free a tempcell */
771 {
772 	if (freeable(a)) {
773 		dprintf(("freeing %s %s %o\n",
774 		    NN(a->nval), NN(a->sval), a->tval));
775 		xfree(a->sval);
776 	}
777 	if (a == tmps)
778 		FATAL("tempcell list is curdled");
779 	a->cnext = tmps;
780 	tmps = a;
781 }
782 
783 static Cell *
784 gettemp(void)	/* get a tempcell */
785 {
786 	int i;
787 	Cell *x;
788 
789 	if (!tmps) {
790 		tmps = (Cell *)calloc(100, sizeof (Cell));
791 		if (!tmps)
792 			FATAL("out of space for temporaries");
793 		for (i = 1; i < 100; i++)
794 			tmps[i-1].cnext = &tmps[i];
795 		tmps[i-1].cnext = NULL;
796 	}
797 	x = tmps;
798 	tmps = x->cnext;
799 	*x = tempcell;
800 	dprintf(("gtemp %.8s %06lo\n", NN(x->nval), (ulong_t)x));
801 	return (x);
802 }
803 
804 /*ARGSUSED*/
805 Cell *
806 indirect(Node **a, int n)	/* $( a[0] ) */
807 {
808 	Awkfloat val;
809 	Cell *x;
810 	int m;
811 	char *s;
812 
813 	x = execute(a[0]);
814 
815 	/* freebsd: defend against super large field numbers */
816 	val = getfval(x);
817 	if ((Awkfloat)INT_MAX < val)
818 		FATAL("trying to access out of range field %s", x->nval);
819 	m = (int)val;
820 	if (m == 0 && !is_number(s = getsval(x)))	/* suspicion! */
821 		FATAL("illegal field $(%s), name \"%s\"", s, x->nval);
822 		/* BUG: can x->nval ever be null??? */
823 	tempfree(x);
824 	x = fieldadr(m);
825 	x->ctype = OCELL;	/* BUG?  why are these needed? */
826 	x->csub = CFLD;
827 	return (x);
828 }
829 
830 /*ARGSUSED*/
831 Cell *
832 substr(Node **a, int nnn)		/* substr(a[0], a[1], a[2]) */
833 {
834 	int k, m, n;
835 	char *s;
836 	int temp;
837 	Cell *x, *y, *z = NULL;
838 
839 	x = execute(a[0]);
840 	y = execute(a[1]);
841 	if (a[2] != NULL)
842 		z = execute(a[2]);
843 	s = getsval(x);
844 	k = strlen(s) + 1;
845 	if (k <= 1) {
846 		tempfree(x);
847 		tempfree(y);
848 		if (a[2] != NULL) {
849 			tempfree(z);
850 		}
851 		x = gettemp();
852 		(void) setsval(x, "");
853 		return (x);
854 	}
855 	m = (int)getfval(y);
856 	if (m <= 0)
857 		m = 1;
858 	else if (m > k)
859 		m = k;
860 	tempfree(y);
861 	if (a[2] != NULL) {
862 		n = (int)getfval(z);
863 		tempfree(z);
864 	} else
865 		n = k - 1;
866 	if (n < 0)
867 		n = 0;
868 	else if (n > k - m)
869 		n = k - m;
870 	dprintf(("substr: m=%d, n=%d, s=%s\n", m, n, s));
871 	y = gettemp();
872 	temp = s[n + m - 1];	/* with thanks to John Linderman */
873 	s[n + m - 1] = '\0';
874 	(void) setsval(y, s + m - 1);
875 	s[n + m - 1] = temp;
876 	tempfree(x);
877 	return (y);
878 }
879 
880 /*ARGSUSED*/
881 Cell *
882 sindex(Node **a, int nnn)		/* index(a[0], a[1]) */
883 {
884 	Cell *x, *y, *z;
885 	char *s1, *s2, *p1, *p2, *q;
886 	Awkfloat v = 0.0;
887 
888 	x = execute(a[0]);
889 	s1 = getsval(x);
890 	y = execute(a[1]);
891 	s2 = getsval(y);
892 
893 	z = gettemp();
894 	for (p1 = s1; *p1 != '\0'; p1++) {
895 		for (q = p1, p2 = s2; *p2 != '\0' && *q == *p2; q++, p2++)
896 			;
897 		if (*p2 == '\0') {
898 			v = (Awkfloat) (p1 - s1 + 1);	/* origin 1 */
899 			break;
900 		}
901 	}
902 	tempfree(x);
903 	tempfree(y);
904 	(void) setfval(z, v);
905 	return (z);
906 }
907 
908 #define	MAXNUMSIZE	50
909 
910 /* printf-like conversions */
911 int
912 format(char **pbuf, int *pbufsize, const char *s, Node *a)
913 {
914 	char *fmt;
915 	const char *os;
916 	Cell *x;
917 	int flag = 0, n, len;
918 	int fmtwd; /* format width */
919 	char *buf = *pbuf;
920 	size_t bufsize = *pbufsize;
921 	size_t fmtsz = recsize;
922 	size_t cnt, tcnt, ret;
923 
924 	os = s;
925 	cnt = 0;
926 	if ((fmt = (char *)malloc(fmtsz)) == NULL)
927 		FATAL("out of memory in format()");
928 	while (*s) {
929 		if (*s != '%') {
930 			expand_buf(&buf, &bufsize, cnt);
931 			buf[cnt++] = *s++;
932 			continue;
933 		}
934 		if (*(s+1) == '%') {
935 			expand_buf(&buf, &bufsize, cnt);
936 			buf[cnt++] = '%';
937 			s += 2;
938 			continue;
939 		}
940 		/*
941 		 * have to be real careful in case this is a huge number,
942 		 * eg, "%100000d".
943 		 */
944 		fmtwd = atoi(s+1);
945 		if (fmtwd < 0)
946 			fmtwd = -fmtwd;
947 		for (tcnt = 0; ; s++) {
948 			expand_buf(&fmt, &fmtsz, tcnt);
949 			fmt[tcnt++] = *s;
950 			if (*s == '\0')
951 				break;
952 			if (isalpha((uschar)*s) &&
953 			    *s != 'l' && *s != 'h' && *s != 'L')
954 				break;	/* the ansi panoply */
955 			if (*s == '$') {
956 				FATAL("'$' not permitted in awk formats");
957 			}
958 			if (*s == '*') {
959 				if (a == NULL) {
960 					FATAL("not enough args in printf(%s) "
961 					    "or sprintf(%s)", os, os);
962 				}
963 				x = execute(a);
964 				a = a->nnext;
965 				tcnt--;
966 				expand_buf(&fmt, &fmtsz, tcnt + 12);
967 				fmtwd = (int)getfval(x);
968 				ret = sprintf(&fmt[tcnt], "%d", fmtwd);
969 				if (fmtwd < 0)
970 					fmtwd = -fmtwd;
971 				tcnt += ret;
972 				tempfree(x);
973 			}
974 		}
975 		fmt[tcnt] = '\0';
976 		if (fmtwd < 0)
977 			fmtwd = -fmtwd;
978 
979 		switch (*s) {
980 		case 'a': case 'A':
981 			flag = *s;
982 			break;
983 		case 'f': case 'e': case 'g': case 'E': case 'G':
984 			flag = 'f';
985 			break;
986 		case 'd': case 'i':
987 			flag = 'd';
988 			if (*(s-1) == 'l')
989 				break;
990 			fmt[tcnt - 1] = 'l';
991 			expand_buf(&fmt, &fmtsz, tcnt);
992 			fmt[tcnt++] = 'd';
993 			fmt[tcnt] = '\0';
994 			break;
995 		case 'o': case 'x': case 'X': case 'u':
996 			flag = *(s-1) == 'l' ? 'd' : 'u';
997 			break;
998 		case 's':
999 			flag = 's';
1000 			break;
1001 		case 'c':
1002 			flag = 'c';
1003 			break;
1004 		default:
1005 			WARNING("weird printf conversion %s", fmt);
1006 			flag = '?';
1007 			break;
1008 		}
1009 		if (flag == '?') {
1010 			len = strlen(fmt);
1011 			expand_buf(&buf, &bufsize, cnt + len);
1012 			(void) memcpy(&buf[cnt], fmt, len);
1013 			cnt += len;
1014 			buf[cnt] = '\0';
1015 			continue;
1016 		}
1017 		if (a == NULL) {
1018 			FATAL("not enough args in printf(%s) "
1019 			    "or sprintf(%s)", os, os);
1020 		}
1021 		x = execute(a);
1022 		a = a->nnext;
1023 		n = MAXNUMSIZE;
1024 		if (fmtwd > n)
1025 			n = fmtwd;
1026 retry:
1027 		/* make sure we have at least 1 byte space */
1028 		(void) adjbuf(&buf, &bufsize, 1 + n + cnt,
1029 		    recsize, NULL, "format5");
1030 		len = bufsize - cnt;
1031 		switch (flag) {
1032 		case 'a':
1033 		case 'A':
1034 		case 'f':
1035 			/*LINTED*/
1036 			ret = snprintf(&buf[cnt], len,
1037 			    fmt, getfval(x));
1038 			break;
1039 		case 'd':
1040 			/*LINTED*/
1041 			ret = snprintf(&buf[cnt], len,
1042 			    fmt, (long)getfval(x));
1043 			break;
1044 		case 'u':
1045 			/*LINTED*/
1046 			ret = snprintf(&buf[cnt], len,
1047 			    fmt, (int)getfval(x));
1048 			break;
1049 		case 's':
1050 			/*LINTED*/
1051 			ret = snprintf(&buf[cnt], len,
1052 			    fmt, getsval(x));
1053 			break;
1054 		case 'c':
1055 			if (!isnum(x)) {
1056 				/*LINTED*/
1057 				ret = snprintf(&buf[cnt], len,
1058 				    fmt, getsval(x)[0]);
1059 				break;
1060 			}
1061 			if (getfval(x)) {
1062 				/*LINTED*/
1063 				ret = snprintf(&buf[cnt], len,
1064 				    fmt, (int)getfval(x));
1065 			} else {
1066 				/* explicit null byte */
1067 				buf[cnt] = '\0';
1068 				/* next output will start here */
1069 				buf[cnt + 1] = '\0';
1070 				ret = 1;
1071 			}
1072 			break;
1073 		default:
1074 			FATAL("can't happen: "
1075 			    "bad conversion %c in format()", flag);
1076 		}
1077 		if (ret >= len) {
1078 			(void) adjbuf(&buf, &bufsize, cnt + ret + 1,
1079 			    recsize, NULL, "format6");
1080 			goto retry;
1081 		}
1082 		tempfree(x);
1083 		cnt += ret;
1084 		s++;
1085 	}
1086 	buf[cnt] = '\0';
1087 	free(fmt);
1088 	for (; a != NULL; a = a->nnext)	/* evaluate any remaining args */
1089 		(void) execute(a);
1090 	*pbuf = buf;
1091 	*pbufsize = bufsize;
1092 	return (cnt);
1093 }
1094 
1095 /*ARGSUSED*/
1096 Cell *
1097 awksprintf(Node **a, int n)		/* sprintf(a[0]) */
1098 {
1099 	Cell *x;
1100 	Node *y;
1101 	char *buf;
1102 	int bufsz = 3 * recsize;
1103 
1104 	if ((buf = (char *)malloc(bufsz)) == NULL)
1105 		FATAL("out of memory in awksprintf");
1106 	y = a[0]->nnext;
1107 	x = execute(a[0]);
1108 	if (format(&buf, &bufsz, getsval(x), y) == -1)
1109 		FATAL("sprintf string %.30s... too long.  can't happen.", buf);
1110 	tempfree(x);
1111 	x = gettemp();
1112 	x->sval = buf;
1113 	x->tval = STR;
1114 	return (x);
1115 }
1116 
1117 /*ARGSUSED*/
1118 Cell *
1119 awkprintf(Node **a, int n)		/* printf */
1120 {
1121 	/* a[0] is list of args, starting with format string */
1122 	/* a[1] is redirection operator, a[2] is redirection file */
1123 	FILE *fp;
1124 	Cell *x;
1125 	Node *y;
1126 	char *buf;
1127 	int len;
1128 	int bufsz = 3 * recsize;
1129 
1130 	if ((buf = (char *)malloc(bufsz)) == NULL)
1131 		FATAL("out of memory in awkprintf");
1132 	y = a[0]->nnext;
1133 	x = execute(a[0]);
1134 	if ((len = format(&buf, &bufsz, getsval(x), y)) == -1)
1135 		FATAL("printf string %.30s... too long. can't happen.", buf);
1136 	tempfree(x);
1137 	if (a[1] == NULL) {
1138 		(void) fwrite(buf, len, 1, stdout);
1139 		if (ferror(stdout))
1140 			FATAL("write error on stdout");
1141 	} else {
1142 		fp = redirect(ptoi(a[1]), a[2]);
1143 		(void) fwrite(buf, len, 1, fp);
1144 		(void) fflush(fp);
1145 		if (ferror(fp))
1146 			FATAL("write error on %s", filename(fp));
1147 	}
1148 	free(buf);
1149 	return (True);
1150 }
1151 
1152 Cell *
1153 arith(Node **a, int n)	/* a[0] + a[1], etc.  also -a[0] */
1154 {
1155 	Awkfloat i, j = 0;
1156 	double v;
1157 	Cell *x, *y, *z;
1158 
1159 	x = execute(a[0]);
1160 	i = getfval(x);
1161 	tempfree(x);
1162 	if (n != UMINUS && n != UPLUS) {
1163 		y = execute(a[1]);
1164 		j = getfval(y);
1165 		tempfree(y);
1166 	}
1167 	z = gettemp();
1168 	switch (n) {
1169 	case ADD:
1170 		i += j;
1171 		break;
1172 	case MINUS:
1173 		i -= j;
1174 		break;
1175 	case MULT:
1176 		i *= j;
1177 		break;
1178 	case DIVIDE:
1179 		if (j == 0)
1180 			FATAL("division by zero");
1181 		i /= j;
1182 		break;
1183 	case MOD:
1184 		if (j == 0)
1185 			FATAL("division by zero in mod");
1186 		(void) modf(i/j, &v);
1187 		i = i - j * v;
1188 		break;
1189 	case UMINUS:
1190 		i = -i;
1191 		break;
1192 	case UPLUS: /* handled by getfval(), above */
1193 		break;
1194 	case POWER:
1195 		if (j >= 0 && modf(j, &v) == 0.0) /* pos integer exponent */
1196 			i = ipow(i, (int)j);
1197 		else
1198 			i = errcheck(pow(i, j), "pow");
1199 		break;
1200 	default:	/* can't happen */
1201 		FATAL("illegal arithmetic operator %d", n);
1202 	}
1203 	(void) setfval(z, i);
1204 	return (z);
1205 }
1206 
1207 static double
1208 ipow(double x, int n)	/* x**n.  ought to be done by pow, but isn't always */
1209 {
1210 	double v;
1211 
1212 	if (n <= 0)
1213 		return (1.0);
1214 	v = ipow(x, n/2);
1215 	if (n % 2 == 0)
1216 		return (v * v);
1217 	else
1218 		return (x * v * v);
1219 }
1220 
1221 Cell *
1222 incrdecr(Node **a, int n)		/* a[0]++, etc. */
1223 {
1224 	Cell *x, *z;
1225 	int k;
1226 	Awkfloat xf;
1227 
1228 	x = execute(a[0]);
1229 	xf = getfval(x);
1230 	k = (n == PREINCR || n == POSTINCR) ? 1 : -1;
1231 	if (n == PREINCR || n == PREDECR) {
1232 		(void) setfval(x, xf + k);
1233 		return (x);
1234 	}
1235 	z = gettemp();
1236 	(void) setfval(z, xf);
1237 	(void) setfval(x, xf + k);
1238 	tempfree(x);
1239 	return (z);
1240 }
1241 
1242 /* a[0] = a[1], a[0] += a[1], etc. */
1243 /* this is subtle; don't muck with it. */
1244 Cell *
1245 assign(Node **a, int n)
1246 {
1247 	Cell *x, *y;
1248 	Awkfloat xf, yf;
1249 	double v;
1250 
1251 	y = execute(a[1]);
1252 	x = execute(a[0]);	/* order reversed from before... */
1253 	if (n == ASSIGN) {	/* ordinary assignment */
1254 		/*LINTED if*/
1255 		if (x == y && !(x->tval & (FLD|REC)) && x != nfloc) {
1256 			/*
1257 			 * If this is a self-assignment, we leave things alone,
1258 			 * unless it's a field or NF.
1259 			 */
1260 		} else if ((y->tval & (STR|NUM)) == (STR|NUM)) {
1261 			(void) setsval(x, getsval(y));
1262 			x->fval = getfval(y);
1263 			x->tval |= NUM;
1264 		} else if (isstr(y))
1265 			(void) setsval(x, getsval(y));
1266 		else if (isnum(y))
1267 			(void) setfval(x, getfval(y));
1268 		else
1269 			funnyvar(y, "read value of");
1270 		tempfree(y);
1271 		return (x);
1272 	}
1273 	xf = getfval(x);
1274 	yf = getfval(y);
1275 	switch (n) {
1276 	case ADDEQ:
1277 		xf += yf;
1278 		break;
1279 	case SUBEQ:
1280 		xf -= yf;
1281 		break;
1282 	case MULTEQ:
1283 		xf *= yf;
1284 		break;
1285 	case DIVEQ:
1286 		if (yf == 0)
1287 			FATAL("division by zero in /=");
1288 		xf /= yf;
1289 		break;
1290 	case MODEQ:
1291 		if (yf == 0)
1292 			FATAL("division by zero in %%=");
1293 		(void) modf(xf/yf, &v);
1294 		xf = xf - yf * v;
1295 		break;
1296 	case POWEQ:
1297 		if (yf >= 0 && modf(yf, &v) == 0.0) /* pos integer exponent */
1298 			xf = ipow(xf, (int)yf);
1299 		else
1300 			xf = errcheck(pow(xf, yf), "pow");
1301 		break;
1302 	default:
1303 		FATAL("illegal assignment operator %d", n);
1304 		break;
1305 	}
1306 	tempfree(y);
1307 	(void) setfval(x, xf);
1308 	return (x);
1309 }
1310 
1311 /*ARGSUSED*/
1312 Cell *
1313 cat(Node **a, int q)	/* a[0] cat a[1] */
1314 {
1315 	Cell *x, *y, *z;
1316 	int n1, n2;
1317 	char *s = NULL;
1318 	size_t ssz = 0;
1319 
1320 	x = execute(a[0]);
1321 	n1 = strlen(getsval(x));
1322 	(void) adjbuf(&s, &ssz, n1 + 1, recsize, 0, "cat1");
1323 	(void) strncpy(s, x->sval, ssz);
1324 
1325 	y = execute(a[1]);
1326 	n2 = strlen(getsval(y));
1327 	(void) adjbuf(&s, &ssz, n1 + n2 + 1, recsize, 0, "cat2");
1328 	(void) strncpy(s + n1, y->sval, ssz - n1);
1329 
1330 	tempfree(x);
1331 	tempfree(y);
1332 
1333 	z = gettemp();
1334 	z->sval = s;
1335 	z->tval = STR;
1336 
1337 	return (z);
1338 }
1339 
1340 /*ARGSUSED*/
1341 Cell *
1342 pastat(Node **a, int n)	/* a[0] { a[1] } */
1343 {
1344 	Cell *x;
1345 
1346 	if (a[0] == NULL)
1347 		x = execute(a[1]);
1348 	else {
1349 		x = execute(a[0]);
1350 		if (istrue(x)) {
1351 			tempfree(x);
1352 			x = execute(a[1]);
1353 		}
1354 	}
1355 	return (x);
1356 }
1357 
1358 /*ARGSUSED*/
1359 Cell *
1360 dopa2(Node **a, int n)	/* a[0], a[1] { a[2] } */
1361 {
1362 	Cell	*x;
1363 	int	pair;
1364 
1365 	if (!pairstack) {
1366 		/* first time */
1367 		dprintf(("paircnt: %d\n", paircnt));
1368 		pairstack = (int *)calloc(paircnt, sizeof (int));
1369 		if (pairstack == NULL)
1370 			FATAL("out of space in dopa2");
1371 	}
1372 
1373 	pair = ptoi(a[3]);
1374 	if (pairstack[pair] == 0) {
1375 		x = execute(a[0]);
1376 		if (istrue(x))
1377 			pairstack[pair] = 1;
1378 		tempfree(x);
1379 	}
1380 	if (pairstack[pair] == 1) {
1381 		x = execute(a[1]);
1382 		if (istrue(x))
1383 			pairstack[pair] = 0;
1384 		tempfree(x);
1385 		x = execute(a[2]);
1386 		return (x);
1387 	}
1388 	return (False);
1389 }
1390 
1391 /*ARGSUSED*/
1392 Cell *
1393 split(Node **a, int nnn)	/* split(a[0], a[1], a[2]); a[3] is type */
1394 {
1395 	Cell *x = NULL, *y, *ap;
1396 	char *s, *origs;
1397 	char *fs, *origfs = NULL;
1398 	int sep;
1399 	char *t, temp, num[50];
1400 	int n, tempstat, arg3type;
1401 
1402 	y = execute(a[0]);	/* source string */
1403 	origs = s = tostring(getsval(y));
1404 	arg3type = ptoi(a[3]);
1405 	if (a[2] == NULL)	/* fs string */
1406 		fs = getsval(fsloc);
1407 	else if (arg3type == STRING) {	/* split(str,arr,"string") */
1408 		x = execute(a[2]);
1409 		origfs = fs = tostring(getsval(x));
1410 		tempfree(x);
1411 	} else if (arg3type == REGEXPR)
1412 		fs = "(regexpr)";	/* split(str,arr,/regexpr/) */
1413 	else
1414 		FATAL("illegal type of split");
1415 	sep = *fs;
1416 	ap = execute(a[1]);	/* array name */
1417 	freesymtab(ap);
1418 	dprintf(("split: s=|%s|, a=%s, sep=|%s|\n", s, NN(ap->nval), fs));
1419 	ap->tval &= ~STR;
1420 	ap->tval |= ARR;
1421 	ap->sval = (char *)makesymtab(NSYMTAB);
1422 
1423 	n = 0;
1424 	if (arg3type == REGEXPR && strlen((char *)((fa*)a[2])->restr) == 0) {
1425 		/*
1426 		 * split(s, a, //); have to arrange things such that it looks
1427 		 * like an empty separator.
1428 		 */
1429 		arg3type = 0;
1430 		fs = "";
1431 		sep = 0;
1432 	}
1433 	if (*s != '\0' && (strlen(fs) > 1 || arg3type == REGEXPR)) {
1434 		/* reg expr */
1435 		fa *pfa;
1436 		if (arg3type == REGEXPR) {	/* it's ready already */
1437 			pfa = (fa *)a[2];
1438 		} else {
1439 			pfa = makedfa(fs, 1);
1440 		}
1441 		if (nematch(pfa, s)) {
1442 			tempstat = pfa->initstat;
1443 			pfa->initstat = 2;
1444 			do {
1445 				n++;
1446 				(void) sprintf(num, "%d", n);
1447 				temp = *patbeg;
1448 				*patbeg = '\0';
1449 				if (is_number(s)) {
1450 					(void) setsymtab(num, s,
1451 					    atof(s),
1452 					    /*LINTED align*/
1453 					    STR|NUM, (Array *)ap->sval);
1454 				} else {
1455 					(void) setsymtab(num, s, 0.0,
1456 					    /*LINTED align*/
1457 					    STR, (Array *)ap->sval);
1458 				}
1459 				*patbeg = temp;
1460 				s = patbeg + patlen;
1461 				if (*(patbeg+patlen-1) == 0 || *s == 0) {
1462 					n++;
1463 					(void) sprintf(num, "%d", n);
1464 					(void) setsymtab(num, "", 0.0,
1465 					    /*LINTED align*/
1466 					    STR, (Array *)ap->sval);
1467 					pfa->initstat = tempstat;
1468 					goto spdone;
1469 				}
1470 			} while (nematch(pfa, s));
1471 			/* bwk: has to be here to reset */
1472 			/* cf gsub and refldbld */
1473 			pfa->initstat = tempstat;
1474 		}
1475 		n++;
1476 		(void) sprintf(num, "%d", n);
1477 		if (is_number(s)) {
1478 			(void) setsymtab(num, s, atof(s),
1479 			    /*LINTED align*/
1480 			    STR|NUM, (Array *)ap->sval);
1481 		} else {
1482 			/*LINTED align*/
1483 			(void) setsymtab(num, s, 0.0, STR, (Array *)ap->sval);
1484 		}
1485 spdone:
1486 		pfa = NULL;
1487 	} else if (sep == ' ') {
1488 		for (n = 0; ; ) {
1489 			while (*s == ' ' || *s == '\t' || *s == '\n')
1490 				s++;
1491 			if (*s == '\0')
1492 				break;
1493 			n++;
1494 			t = s;
1495 			do
1496 				s++;
1497 			while (*s != ' ' && *s != '\t' &&
1498 			    *s != '\n' && *s != '\0')
1499 				;
1500 			temp = *s;
1501 			*s = '\0';
1502 			(void) sprintf(num, "%d", n);
1503 			if (is_number(t)) {
1504 				(void) setsymtab(num, t, atof(t),
1505 				    /*LINTED align*/
1506 				    STR|NUM, (Array *)ap->sval);
1507 			} else {
1508 				(void) setsymtab(num, t, 0.0,
1509 				    /*LINTED align*/
1510 				    STR, (Array *)ap->sval);
1511 			}
1512 			*s = temp;
1513 			if (*s != '\0')
1514 				s++;
1515 		}
1516 	} else if (sep == '\0') {	/* split(s, a, "") => 1 char/elem */
1517 		for (n = 0; *s != 0; s++) {
1518 			char buf[2];
1519 			n++;
1520 			(void) sprintf(num, "%d", n);
1521 			buf[0] = *s;
1522 			buf[1] = '\0';
1523 			if (isdigit((uschar)buf[0])) {
1524 				(void) setsymtab(num, buf, atof(buf),
1525 				    /*LINTED align*/
1526 				    STR|NUM, (Array *)ap->sval);
1527 			} else {
1528 				(void) setsymtab(num, buf, 0.0,
1529 				    /*LINTED align*/
1530 				    STR, (Array *)ap->sval);
1531 			}
1532 		}
1533 	} else if (*s != '\0') {
1534 		for (;;) {
1535 			n++;
1536 			t = s;
1537 			while (*s != sep && *s != '\n' && *s != '\0')
1538 				s++;
1539 			temp = *s;
1540 			*s = '\0';
1541 			(void) sprintf(num, "%d", n);
1542 			if (is_number(t)) {
1543 				(void) setsymtab(num, t, atof(t),
1544 				    /*LINTED align*/
1545 				    STR|NUM, (Array *)ap->sval);
1546 			} else {
1547 				(void) setsymtab(num, t, 0.0,
1548 				    /*LINTED align*/
1549 				    STR, (Array *)ap->sval);
1550 			}
1551 			*s = temp;
1552 			if (*s++ == '\0')
1553 				break;
1554 		}
1555 	}
1556 	tempfree(ap);
1557 	tempfree(y);
1558 	free(origs);
1559 	free(origfs);
1560 	x = gettemp();
1561 	x->tval = NUM;
1562 	x->fval = n;
1563 	return (x);
1564 }
1565 
1566 /*ARGSUSED*/
1567 Cell *
1568 condexpr(Node **a, int n)	/* a[0] ? a[1] : a[2] */
1569 {
1570 	Cell *x;
1571 
1572 	x = execute(a[0]);
1573 	if (istrue(x)) {
1574 		tempfree(x);
1575 		x = execute(a[1]);
1576 	} else {
1577 		tempfree(x);
1578 		x = execute(a[2]);
1579 	}
1580 	return (x);
1581 }
1582 
1583 /*ARGSUSED*/
1584 Cell *
1585 ifstat(Node **a, int n)	/* if (a[0]) a[1]; else a[2] */
1586 {
1587 	Cell *x;
1588 
1589 	x = execute(a[0]);
1590 	if (istrue(x)) {
1591 		tempfree(x);
1592 		x = execute(a[1]);
1593 	} else if (a[2] != NULL) {
1594 		tempfree(x);
1595 		x = execute(a[2]);
1596 	}
1597 	return (x);
1598 }
1599 
1600 /*ARGSUSED*/
1601 Cell *
1602 whilestat(Node **a, int n)	/* while (a[0]) a[1] */
1603 {
1604 	Cell *x;
1605 
1606 	for (;;) {
1607 		x = execute(a[0]);
1608 		if (!istrue(x))
1609 			return (x);
1610 		tempfree(x);
1611 		x = execute(a[1]);
1612 		if (isbreak(x)) {
1613 			x = True;
1614 			return (x);
1615 		}
1616 		if (isnext(x) || isexit(x) || isret(x))
1617 			return (x);
1618 		tempfree(x);
1619 	}
1620 }
1621 
1622 /*ARGSUSED*/
1623 Cell *
1624 dostat(Node **a, int n)	/* do a[0]; while(a[1]) */
1625 {
1626 	Cell *x;
1627 
1628 	for (;;) {
1629 		x = execute(a[0]);
1630 		if (isbreak(x))
1631 			return (True);
1632 		if (isnext(x) || isexit(x) || isret(x))
1633 			return (x);
1634 		tempfree(x);
1635 		x = execute(a[1]);
1636 		if (!istrue(x))
1637 			return (x);
1638 		tempfree(x);
1639 	}
1640 }
1641 
1642 /*ARGSUSED*/
1643 Cell *
1644 forstat(Node **a, int n)	/* for (a[0]; a[1]; a[2]) a[3] */
1645 {
1646 	Cell *x;
1647 
1648 	x = execute(a[0]);
1649 	tempfree(x);
1650 	for (;;) {
1651 		if (a[1] != NULL) {
1652 			x = execute(a[1]);
1653 			if (!istrue(x))
1654 				return (x);
1655 			else
1656 				tempfree(x);
1657 		}
1658 		x = execute(a[3]);
1659 		if (isbreak(x))		/* turn off break */
1660 			return (True);
1661 		if (isnext(x) || isexit(x) || isret(x))
1662 			return (x);
1663 		tempfree(x);
1664 		x = execute(a[2]);
1665 		tempfree(x);
1666 	}
1667 }
1668 
1669 /*ARGSUSED*/
1670 Cell *
1671 instat(Node **a, int n)	/* for (a[0] in a[1]) a[2] */
1672 {
1673 	Cell *x, *vp, *arrayp, *cp, *ncp;
1674 	Array *tp;
1675 	int i;
1676 
1677 	vp = execute(a[0]);
1678 	arrayp = execute(a[1]);
1679 	if (!isarr(arrayp)) {
1680 		dprintf(("making %s into an array\n", arrayp->nval));
1681 		if (freeable(arrayp))
1682 			xfree(arrayp->sval);
1683 		arrayp->tval &= ~(STR|NUM|DONTFREE);
1684 		arrayp->tval |= ARR;
1685 		arrayp->sval = (char *)makesymtab(NSYMTAB);
1686 	}
1687 	/*LINTED align*/
1688 	tp = (Array *)arrayp->sval;
1689 	tempfree(arrayp);
1690 	for (i = 0; i < tp->size; i++) { /* this routine knows too much */
1691 		for (cp = tp->tab[i]; cp != NULL; cp = ncp) {
1692 			(void) setsval(vp, cp->nval);
1693 			ncp = cp->cnext;
1694 			x = execute(a[2]);
1695 			if (isbreak(x)) {
1696 				tempfree(vp);
1697 				return (True);
1698 			}
1699 			if (isnext(x) || isexit(x) || isret(x)) {
1700 				tempfree(vp);
1701 				return (x);
1702 			}
1703 			tempfree(x);
1704 		}
1705 	}
1706 	return (True);
1707 }
1708 
1709 /*ARGSUSED*/
1710 Cell *
1711 bltin(Node **a, int n)	/* builtin functions. a[0] is type, a[1] is arg list */
1712 {
1713 	Cell *x, *y;
1714 	Awkfloat u;
1715 	int t;
1716 	Awkfloat tmp;
1717 	char *p, *buf;
1718 	Node *nextarg;
1719 	FILE *fp;
1720 	void flush_all(void);
1721 	int status = 0;
1722 
1723 	t = ptoi(a[0]);
1724 	x = execute(a[1]);
1725 	nextarg = a[1]->nnext;
1726 	switch (t) {
1727 	case FLENGTH:
1728 		if (isarr(x)) {
1729 			/* LINTED align */
1730 			u = ((Array *)x->sval)->nelem;
1731 		} else {
1732 			u = strlen(getsval(x));
1733 		}
1734 		break;
1735 	case FLOG:
1736 		u = errcheck(log(getfval(x)), "log"); break;
1737 	case FINT:
1738 		(void) modf(getfval(x), &u); break;
1739 	case FEXP:
1740 		u = errcheck(exp(getfval(x)), "exp"); break;
1741 	case FSQRT:
1742 		u = errcheck(sqrt(getfval(x)), "sqrt"); break;
1743 	case FSIN:
1744 		u = sin(getfval(x)); break;
1745 	case FCOS:
1746 		u = cos(getfval(x)); break;
1747 	case FATAN:
1748 		if (nextarg == NULL) {
1749 			WARNING("atan2 requires two arguments; returning 1.0");
1750 			u = 1.0;
1751 		} else {
1752 			y = execute(a[1]->nnext);
1753 			u = atan2(getfval(x), getfval(y));
1754 			tempfree(y);
1755 			nextarg = nextarg->nnext;
1756 		}
1757 		break;
1758 	case FSYSTEM:
1759 		/* in case something is buffered already */
1760 		(void) fflush(stdout);
1761 		status = system(getsval(x));
1762 		u = status;
1763 		if (status != -1) {
1764 			if (WIFEXITED(status)) {
1765 				u = WEXITSTATUS(status);
1766 			} else if (WIFSIGNALED(status)) {
1767 				u = WTERMSIG(status) + 256;
1768 				if (WCOREDUMP(status))
1769 					u += 256;
1770 			} else	/* something else?!? */
1771 				u = 0;
1772 		}
1773 		break;
1774 	case FRAND:
1775 		/* in principle, rand() returns something in 0..RAND_MAX */
1776 		u = (Awkfloat) (rand() % RAND_MAX) / RAND_MAX;
1777 		break;
1778 	case FSRAND:
1779 		if (isrec(x))	/* no argument provided */
1780 			u = time((time_t *)0);
1781 		else
1782 			u = getfval(x);
1783 		tmp = u;
1784 		srand((unsigned int) u);
1785 		u = srand_seed;
1786 		srand_seed = tmp;
1787 		break;
1788 	case FTOUPPER:
1789 	case FTOLOWER:
1790 		buf = tostring(getsval(x));
1791 		if (t == FTOUPPER) {
1792 			for (p = buf; *p; p++)
1793 				if (islower((uschar)*p))
1794 					*p = toupper((uschar)*p);
1795 		} else {
1796 			for (p = buf; *p; p++)
1797 				if (isupper((uschar)*p))
1798 					*p = tolower((uschar)*p);
1799 		}
1800 		tempfree(x);
1801 		x = gettemp();
1802 		(void) setsval(x, buf);
1803 		free(buf);
1804 		return (x);
1805 	case FFLUSH:
1806 		if (isrec(x) || strlen(getsval(x)) == 0) {
1807 			flush_all();	/* fflush() or fflush("") -> all */
1808 			u = 0;
1809 		} else if ((fp = openfile(FFLUSH, getsval(x))) == NULL)
1810 			u = EOF;
1811 		else
1812 			u = fflush(fp);
1813 		break;
1814 	default:	/* can't happen */
1815 		FATAL("illegal function type %d", t);
1816 		break;
1817 	}
1818 	tempfree(x);
1819 	x = gettemp();
1820 	(void) setfval(x, u);
1821 	if (nextarg != NULL) {
1822 		WARNING("warning: function has too many arguments");
1823 		for (; nextarg != NULL; nextarg = nextarg->nnext)
1824 			(void) execute(nextarg);
1825 	}
1826 	return (x);
1827 }
1828 
1829 /*ARGSUSED*/
1830 Cell *
1831 printstat(Node **a, int n)	/* print a[0] */
1832 {
1833 	Node *x;
1834 	Cell *y;
1835 	FILE *fp;
1836 
1837 	if (a[1] == NULL)	/* a[1] is redirection operator, a[2] is file */
1838 		fp = stdout;
1839 	else
1840 		fp = redirect(ptoi(a[1]), a[2]);
1841 	for (x = a[0]; x != NULL; x = x->nnext) {
1842 		y = execute(x);
1843 		(void) fputs(getpssval(y), fp);
1844 		tempfree(y);
1845 		if (x->nnext == NULL)
1846 			(void) fputs(getsval(orsloc), fp);
1847 		else
1848 			(void) fputs(getsval(ofsloc), fp);
1849 	}
1850 	if (a[1] != NULL)
1851 		(void) fflush(fp);
1852 	if (ferror(fp))
1853 		FATAL("write error on %s", filename(fp));
1854 	return (True);
1855 }
1856 
1857 /*ARGSUSED*/
1858 Cell *
1859 nullproc(Node **a, int n)
1860 {
1861 	return (0);
1862 }
1863 
1864 
1865 static FILE *
1866 redirect(int a, Node *b)	/* set up all i/o redirections */
1867 {
1868 	FILE *fp;
1869 	Cell *x;
1870 	char *fname;
1871 
1872 	x = execute(b);
1873 	fname = getsval(x);
1874 	fp = openfile(a, fname);
1875 	if (fp == NULL)
1876 		FATAL("can't open file %s", fname);
1877 	tempfree(x);
1878 	return (fp);
1879 }
1880 
1881 struct files {
1882 	FILE	*fp;
1883 	const char	*fname;
1884 	int	mode;	/* '|', 'a', 'w' => LE/LT, GT */
1885 } *files;
1886 
1887 int nfiles;
1888 
1889 void
1890 stdinit(void)	/* in case stdin, etc., are not constants */
1891 {
1892 	nfiles = FOPEN_MAX;
1893 	files = calloc(nfiles, sizeof (*files));
1894 	if (files == NULL)
1895 		FATAL("can't allocate file memory for %u files", nfiles);
1896 	files[0].fp = stdin;
1897 	files[0].fname = "/dev/stdin";
1898 	files[0].mode = LT;
1899 	files[1].fp = stdout;
1900 	files[1].fname = "/dev/stdout";
1901 	files[1].mode = GT;
1902 	files[2].fp = stderr;
1903 	files[2].fname = "/dev/stderr";
1904 	files[2].mode = GT;
1905 }
1906 
1907 static FILE *
1908 openfile(int a, const char *s)
1909 {
1910 	int i, m;
1911 	FILE *fp = NULL;
1912 
1913 	if (*s == '\0')
1914 		FATAL("null file name in print or getline");
1915 	for (i = 0; i < nfiles; i++) {
1916 		if (files[i].fname && strcmp(s, files[i].fname) == 0) {
1917 			if (a == files[i].mode ||
1918 			    (a == APPEND && files[i].mode == GT)) {
1919 				return (files[i].fp);
1920 			}
1921 			if (a == FFLUSH)
1922 				return (files[i].fp);
1923 		}
1924 	}
1925 	if (a == FFLUSH)	/* didn't find it, so don't create it! */
1926 		return (NULL);
1927 
1928 	for (i = 0; i < nfiles; i++) {
1929 		if (files[i].fp == 0)
1930 			break;
1931 	}
1932 	if (i >= nfiles) {
1933 		struct files *nf;
1934 		int nnf = nfiles + FOPEN_MAX;
1935 		nf = realloc(files, nnf * sizeof (*nf));
1936 		if (nf == NULL)
1937 			FATAL("cannot grow files for %s and %d files", s, nnf);
1938 		(void) memset(&nf[nfiles], 0, FOPEN_MAX * sizeof (*nf));
1939 		nfiles = nnf;
1940 		files = nf;
1941 	}
1942 	(void) fflush(stdout);	/* force a semblance of order */
1943 	m = a;
1944 	if (a == GT) {
1945 		fp = fopen(s, "wF");
1946 	} else if (a == APPEND) {
1947 		fp = fopen(s, "aF");
1948 		m = GT;	/* so can mix > and >> */
1949 	} else if (a == '|') {	/* output pipe */
1950 		fp = popen(s, "wF");
1951 	} else if (a == LE) {	/* input pipe */
1952 		fp = popen(s, "rF");
1953 	} else if (a == LT) {	/* getline <file */
1954 		fp = strcmp(s, "-") == 0 ?
1955 		    stdin : fopen(s, "rF");	/* "-" is stdin */
1956 	} else	/* can't happen */
1957 		FATAL("illegal redirection %d", a);
1958 	if (fp != NULL) {
1959 		files[i].fname = tostring(s);
1960 		files[i].fp = fp;
1961 		files[i].mode = m;
1962 	}
1963 	return (fp);
1964 }
1965 
1966 const char *
1967 filename(FILE *fp)
1968 {
1969 	int i;
1970 
1971 	for (i = 0; i < nfiles; i++)
1972 		if (fp == files[i].fp)
1973 			return (files[i].fname);
1974 	return ("???");
1975 }
1976 
1977 /*ARGSUSED*/
1978 Cell *
1979 closefile(Node **a, int n)
1980 {
1981 	Cell *x;
1982 	int i, stat;
1983 
1984 	x = execute(a[0]);
1985 	(void) getsval(x);
1986 	stat = -1;
1987 	for (i = 0; i < nfiles; i++) {
1988 		if (files[i].fname && strcmp(x->sval, files[i].fname) == 0) {
1989 			if (ferror(files[i].fp)) {
1990 				WARNING("i/o error occurred on %s",
1991 				    files[i].fname);
1992 			}
1993 			if (files[i].mode == '|' || files[i].mode == LE)
1994 				stat = pclose(files[i].fp);
1995 			else
1996 				stat = fclose(files[i].fp);
1997 			if (stat == EOF) {
1998 				WARNING("i/o error occurred closing %s",
1999 				    files[i].fname);
2000 			}
2001 			if (i > 2)	/* don't do /dev/std... */
2002 				xfree(files[i].fname);
2003 			/* watch out for ref thru this */
2004 			files[i].fname = NULL;
2005 			files[i].fp = NULL;
2006 		}
2007 	}
2008 	tempfree(x);
2009 	x = gettemp();
2010 	(void) setfval(x, (Awkfloat) stat);
2011 	return (x);
2012 }
2013 
2014 static void
2015 closeall(void)
2016 {
2017 	int i, stat;
2018 
2019 	for (i = 0; i < nfiles; i++) {
2020 		if (files[i].fp) {
2021 			if (ferror(files[i].fp)) {
2022 				WARNING("i/o error occurred on %s",
2023 				    files[i].fname);
2024 			}
2025 			if (files[i].mode == '|' || files[i].mode == LE)
2026 				stat = pclose(files[i].fp);
2027 			else
2028 				stat = fclose(files[i].fp);
2029 			if (stat == EOF) {
2030 				WARNING("i/o error occurred while closing %s",
2031 				    files[i].fname);
2032 			}
2033 		}
2034 	}
2035 }
2036 
2037 void
2038 flush_all(void)
2039 {
2040 	int i;
2041 
2042 	for (i = 0; i < nfiles; i++)
2043 		if (files[i].fp)
2044 			(void) fflush(files[i].fp);
2045 }
2046 
2047 /*ARGSUSED*/
2048 Cell *
2049 sub(Node **a, int nnn)	/* substitute command */
2050 {
2051 	char *sptr, *pb, *q;
2052 	Cell *x, *y, *result;
2053 	char *t, *buf;
2054 	fa *pfa;
2055 	size_t bufsz = recsize;
2056 
2057 	if ((buf = (char *)malloc(bufsz)) == NULL)
2058 		FATAL("out of memory in sub");
2059 	x = execute(a[3]);	/* target string */
2060 	t = getsval(x);
2061 	if (a[0] == NULL)	/* 0 => a[1] is already-compiled regexpr */
2062 		pfa = (fa *)a[1];	/* regular expression */
2063 	else {
2064 		y = execute(a[1]);
2065 		pfa = makedfa(getsval(y), 1);
2066 		tempfree(y);
2067 	}
2068 	y = execute(a[2]);	/* replacement string */
2069 	result = False;
2070 	if (pmatch(pfa, t)) {
2071 		sptr = t;
2072 		(void) adjbuf(&buf, &bufsz,
2073 		    1 + patbeg - sptr, recsize, 0, "sub");
2074 		pb = buf;
2075 		while (sptr < patbeg)
2076 			*pb++ = *sptr++;
2077 		sptr = getsval(y);
2078 		while (*sptr != '\0') {
2079 			(void) adjbuf(&buf, &bufsz, 5 + pb - buf,
2080 			    recsize, &pb, "sub");
2081 			if (*sptr == '\\') {
2082 				backsub(&pb, &sptr);
2083 			} else if (*sptr == '&') {
2084 				sptr++;
2085 				(void) adjbuf(&buf, &bufsz,
2086 				    1 + patlen + pb - buf, recsize, &pb, "sub");
2087 				for (q = patbeg; q < patbeg+patlen; )
2088 					*pb++ = *q++;
2089 			} else {
2090 				*pb++ = *sptr++;
2091 			}
2092 		}
2093 		*pb = '\0';
2094 		if (pb > buf + bufsz)
2095 			FATAL("sub result1 %.30s too big; can't happen", buf);
2096 		sptr = patbeg + patlen;
2097 		if ((patlen == 0 && *patbeg) || (patlen && *(sptr-1))) {
2098 			(void) adjbuf(&buf, &bufsz,
2099 			    1 + strlen(sptr) + pb - buf, 0, &pb, "sub");
2100 			while ((*pb++ = *sptr++) != '\0')
2101 				;
2102 		}
2103 		if (pb > buf + bufsz)
2104 			FATAL("sub result2 %.30s too big; can't happen", buf);
2105 		(void) setsval(x, buf);	/* BUG: should be able to avoid copy */
2106 		result = True;
2107 	}
2108 	tempfree(x);
2109 	tempfree(y);
2110 	free(buf);
2111 	return (result);
2112 }
2113 
2114 /*ARGSUSED*/
2115 Cell *
2116 gsub(Node **a, int nnn)	/* global substitute */
2117 {
2118 	Cell *x, *y;
2119 	char *rptr, *sptr, *t, *pb, *q;
2120 	char *buf;
2121 	fa *pfa;
2122 	int mflag, tempstat, num;
2123 	size_t bufsz = recsize;
2124 
2125 	if ((buf = (char *)malloc(bufsz)) == NULL)
2126 		FATAL("out of memory in gsub");
2127 	mflag = 0;	/* if mflag == 0, can replace empty string */
2128 	num = 0;
2129 	x = execute(a[3]);	/* target string */
2130 	t = getsval(x);
2131 	if (a[0] == NULL)	/* 0 => a[1] is already-compiled regexpr */
2132 		pfa = (fa *)a[1];	/* regular expression */
2133 	else {
2134 		y = execute(a[1]);
2135 		pfa = makedfa(getsval(y), 1);
2136 		tempfree(y);
2137 	}
2138 	y = execute(a[2]);	/* replacement string */
2139 	if (pmatch(pfa, t)) {
2140 		tempstat = pfa->initstat;
2141 		pfa->initstat = 2;
2142 		pb = buf;
2143 		rptr = getsval(y);
2144 		do {
2145 			if (patlen == 0 && *patbeg != '\0') {
2146 				/* matched empty string */
2147 				if (mflag == 0) {	/* can replace empty */
2148 					num++;
2149 					sptr = rptr;
2150 					while (*sptr != '\0') {
2151 						(void) adjbuf(&buf, &bufsz,
2152 						    5 + pb - buf, recsize,
2153 						    &pb, "gsub");
2154 						if (*sptr == '\\') {
2155 							backsub(&pb, &sptr);
2156 						} else if (*sptr == '&') {
2157 							sptr++;
2158 							(void) adjbuf(&buf,
2159 							    &bufsz,
2160 							    1+patlen+pb-buf,
2161 							    recsize,
2162 							    &pb, "gsub");
2163 							for (
2164 							    q = patbeg;
2165 							    q < patbeg+patlen;
2166 							    *pb++ = *q++)
2167 								;
2168 						} else {
2169 							*pb++ = *sptr++;
2170 						}
2171 					}
2172 				}
2173 				if (*t == '\0')	/* at end */
2174 					goto done;
2175 				(void) adjbuf(&buf, &bufsz,
2176 				    2 + pb - buf, recsize, &pb, "gsub");
2177 				*pb++ = *t++;
2178 				/* BUG: not sure of this test */
2179 				if (pb > buf + bufsz)
2180 					FATAL("gsub result0 %.30s too big; "
2181 					    "can't happen", buf);
2182 				mflag = 0;
2183 			} else {	/* matched nonempty string */
2184 				num++;
2185 				sptr = t;
2186 				(void) adjbuf(&buf, &bufsz,
2187 				    1 + (patbeg - sptr) + pb - buf,
2188 				    recsize, &pb, "gsub");
2189 				while (sptr < patbeg)
2190 					*pb++ = *sptr++;
2191 				sptr = rptr;
2192 				while (*sptr != '\0') {
2193 					(void) adjbuf(&buf, &bufsz,
2194 					    5 + pb - buf, recsize, &pb, "gsub");
2195 					if (*sptr == '\\') {
2196 						backsub(&pb, &sptr);
2197 					} else if (*sptr == '&') {
2198 						sptr++;
2199 						(void) adjbuf(&buf, &bufsz,
2200 						    1 + patlen + pb - buf,
2201 						    recsize, &pb, "gsub");
2202 						for (
2203 						    q = patbeg;
2204 						    q < patbeg+patlen;
2205 						    *pb++ = *q++)
2206 							;
2207 					} else {
2208 						*pb++ = *sptr++;
2209 					}
2210 				}
2211 				t = patbeg + patlen;
2212 				if (patlen == 0 || *(t-1) == '\0' || *t == '\0')
2213 					goto done;
2214 				if (pb > buf + bufsz)
2215 					FATAL("gsub result1 %.30s too big; "
2216 					    "can't happen", buf);
2217 				mflag = 1;
2218 			}
2219 		} while (pmatch(pfa, t));
2220 		sptr = t;
2221 		(void) adjbuf(&buf, &bufsz,
2222 		    1 + strlen(sptr) + pb - buf, 0, &pb, "gsub");
2223 		while ((*pb++ = *sptr++) != '\0')
2224 			;
2225 	done:
2226 		if (pb < buf + bufsz)
2227 			*pb = '\0';
2228 		else if (*(pb-1) != '\0')
2229 			FATAL("gsub result2 %.30s truncated; "
2230 			    "can't happen", buf);
2231 		/* BUG: should be able to avoid copy + free */
2232 		(void) setsval(x, buf);
2233 		pfa->initstat = tempstat;
2234 	}
2235 	tempfree(x);
2236 	tempfree(y);
2237 	x = gettemp();
2238 	x->tval = NUM;
2239 	x->fval = num;
2240 	free(buf);
2241 	return (x);
2242 }
2243 
2244 /*
2245  * handle \\& variations; sptr[0] == '\\'
2246  */
2247 static void
2248 backsub(char **pb_ptr, char **sptr_ptr)
2249 {
2250 	char *pb = *pb_ptr, *sptr = *sptr_ptr;
2251 
2252 	if (sptr[1] == '\\') {
2253 		if (sptr[2] == '\\' && sptr[3] == '&') { /* \\\& -> \& */
2254 			*pb++ = '\\';
2255 			*pb++ = '&';
2256 			sptr += 4;
2257 		} else if (sptr[2] == '&') {	/* \\& -> \ + matched */
2258 			*pb++ = '\\';
2259 			sptr += 2;
2260 		} else {			/* \\x -> \\x */
2261 			*pb++ = *sptr++;
2262 			*pb++ = *sptr++;
2263 		}
2264 	} else if (sptr[1] == '&') {	/* literal & */
2265 		sptr++;
2266 		*pb++ = *sptr++;
2267 	} else				/* literal \ */
2268 		*pb++ = *sptr++;
2269 
2270 	*pb_ptr = pb;
2271 	*sptr_ptr = sptr;
2272 }
2273