xref: /freebsd/usr.bin/sed/process.c (revision d056fa046c6a91b90cd98165face0e42a33a5173)
1 /*-
2  * Copyright (c) 1992 Diomidis Spinellis.
3  * Copyright (c) 1992, 1993, 1994
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Diomidis Spinellis of Imperial College, University of London.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #ifndef lint
38 static const char sccsid[] = "@(#)process.c	8.6 (Berkeley) 4/20/94";
39 #endif
40 
41 #include <sys/types.h>
42 #include <sys/stat.h>
43 #include <sys/ioctl.h>
44 #include <sys/uio.h>
45 
46 #include <ctype.h>
47 #include <err.h>
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <limits.h>
51 #include <regex.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 #include <wchar.h>
57 #include <wctype.h>
58 
59 #include "defs.h"
60 #include "extern.h"
61 
62 static SPACE HS, PS, SS, YS;
63 #define	pd		PS.deleted
64 #define	ps		PS.space
65 #define	psl		PS.len
66 #define	hs		HS.space
67 #define	hsl		HS.len
68 
69 static __inline int	 applies(struct s_command *);
70 static void		 do_tr(struct s_tr *);
71 static void		 flush_appends(void);
72 static void		 lputs(char *, size_t);
73 static __inline int	 regexec_e(regex_t *, const char *, int, int, size_t);
74 static void		 regsub(SPACE *, char *, char *);
75 static int		 substitute(struct s_command *);
76 
77 struct s_appends *appends;	/* Array of pointers to strings to append. */
78 static int appendx;		/* Index into appends array. */
79 int appendnum;			/* Size of appends array. */
80 
81 static int lastaddr;		/* Set by applies if last address of a range. */
82 static int sdone;		/* If any substitutes since last line input. */
83 				/* Iov structure for 'w' commands. */
84 static regex_t *defpreg;
85 size_t maxnsub;
86 regmatch_t *match;
87 
88 #define OUT(s) { fwrite(s, sizeof(u_char), psl, outfile); fputc('\n', outfile); }
89 
90 void
91 process(void)
92 {
93 	struct s_command *cp;
94 	SPACE tspace;
95 	size_t oldpsl = 0;
96 	char *p;
97 
98 	p = NULL;
99 
100 	for (linenum = 0; mf_fgets(&PS, REPLACE);) {
101 		pd = 0;
102 top:
103 		cp = prog;
104 redirect:
105 		while (cp != NULL) {
106 			if (!applies(cp)) {
107 				cp = cp->next;
108 				continue;
109 			}
110 			switch (cp->code) {
111 			case '{':
112 				cp = cp->u.c;
113 				goto redirect;
114 			case 'a':
115 				if (appendx >= appendnum)
116 					if ((appends = realloc(appends,
117 					    sizeof(struct s_appends) *
118 					    (appendnum *= 2))) == NULL)
119 						err(1, "realloc");
120 				appends[appendx].type = AP_STRING;
121 				appends[appendx].s = cp->t;
122 				appends[appendx].len = strlen(cp->t);
123 				appendx++;
124 				break;
125 			case 'b':
126 				cp = cp->u.c;
127 				goto redirect;
128 			case 'c':
129 				pd = 1;
130 				psl = 0;
131 				if (cp->a2 == NULL || lastaddr)
132 					(void)fprintf(outfile, "%s", cp->t);
133 				break;
134 			case 'd':
135 				pd = 1;
136 				goto new;
137 			case 'D':
138 				if (pd)
139 					goto new;
140 				if (psl == 0 ||
141 				    (p = memchr(ps, '\n', psl)) == NULL) {
142 					pd = 1;
143 					goto new;
144 				} else {
145 					psl -= (p + 1) - ps;
146 					memmove(ps, p + 1, psl);
147 					goto top;
148 				}
149 			case 'g':
150 				cspace(&PS, hs, hsl, REPLACE);
151 				break;
152 			case 'G':
153 				cspace(&PS, "\n", 1, 0);
154 				cspace(&PS, hs, hsl, 0);
155 				break;
156 			case 'h':
157 				cspace(&HS, ps, psl, REPLACE);
158 				break;
159 			case 'H':
160 				cspace(&HS, "\n", 1, 0);
161 				cspace(&HS, ps, psl, 0);
162 				break;
163 			case 'i':
164 				(void)fprintf(outfile, "%s", cp->t);
165 				break;
166 			case 'l':
167 				lputs(ps, psl);
168 				break;
169 			case 'n':
170 				if (!nflag && !pd)
171 					OUT(ps)
172 				flush_appends();
173 				if (!mf_fgets(&PS, REPLACE))
174 					exit(0);
175 				pd = 0;
176 				break;
177 			case 'N':
178 				flush_appends();
179 				cspace(&PS, "\n", 1, 0);
180 				if (!mf_fgets(&PS, 0))
181 					exit(0);
182 				break;
183 			case 'p':
184 				if (pd)
185 					break;
186 				OUT(ps)
187 				break;
188 			case 'P':
189 				if (pd)
190 					break;
191 				if ((p = memchr(ps, '\n', psl)) != NULL) {
192 					oldpsl = psl;
193 					psl = p - ps;
194 				}
195 				OUT(ps)
196 				if (p != NULL)
197 					psl = oldpsl;
198 				break;
199 			case 'q':
200 				if (!nflag && !pd)
201 					OUT(ps)
202 				flush_appends();
203 				exit(0);
204 			case 'r':
205 				if (appendx >= appendnum)
206 					if ((appends = realloc(appends,
207 					    sizeof(struct s_appends) *
208 					    (appendnum *= 2))) == NULL)
209 						err(1, "realloc");
210 				appends[appendx].type = AP_FILE;
211 				appends[appendx].s = cp->t;
212 				appends[appendx].len = strlen(cp->t);
213 				appendx++;
214 				break;
215 			case 's':
216 				sdone |= substitute(cp);
217 				break;
218 			case 't':
219 				if (sdone) {
220 					sdone = 0;
221 					cp = cp->u.c;
222 					goto redirect;
223 				}
224 				break;
225 			case 'w':
226 				if (pd)
227 					break;
228 				if (cp->u.fd == -1 && (cp->u.fd = open(cp->t,
229 				    O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
230 				    DEFFILEMODE)) == -1)
231 					err(1, "%s", cp->t);
232 				if (write(cp->u.fd, ps, psl) != psl ||
233 				    write(cp->u.fd, "\n", 1) != 1)
234 					err(1, "%s", cp->t);
235 				break;
236 			case 'x':
237 				if (hs == NULL)
238 					cspace(&HS, "", 0, REPLACE);
239 				tspace = PS;
240 				PS = HS;
241 				HS = tspace;
242 				break;
243 			case 'y':
244 				if (pd || psl == 0)
245 					break;
246 				do_tr(cp->u.y);
247 				break;
248 			case ':':
249 			case '}':
250 				break;
251 			case '=':
252 				(void)fprintf(outfile, "%lu\n", linenum);
253 			}
254 			cp = cp->next;
255 		} /* for all cp */
256 
257 new:		if (!nflag && !pd)
258 			OUT(ps)
259 		flush_appends();
260 	} /* for all lines */
261 }
262 
263 /*
264  * TRUE if the address passed matches the current program state
265  * (lastline, linenumber, ps).
266  */
267 #define	MATCH(a)						\
268 	(a)->type == AT_RE ? regexec_e((a)->u.r, ps, 0, 1, psl) :	\
269 	    (a)->type == AT_LINE ? linenum == (a)->u.l : lastline()
270 
271 /*
272  * Return TRUE if the command applies to the current line.  Sets the inrange
273  * flag to process ranges.  Interprets the non-select (``!'') flag.
274  */
275 static __inline int
276 applies(struct s_command *cp)
277 {
278 	int r;
279 
280 	lastaddr = 0;
281 	if (cp->a1 == NULL && cp->a2 == NULL)
282 		r = 1;
283 	else if (cp->a2)
284 		if (cp->inrange) {
285 			if (MATCH(cp->a2)) {
286 				cp->inrange = 0;
287 				lastaddr = 1;
288 			}
289 			r = 1;
290 		} else if (MATCH(cp->a1)) {
291 			/*
292 			 * If the second address is a number less than or
293 			 * equal to the line number first selected, only
294 			 * one line shall be selected.
295 			 *	-- POSIX 1003.2
296 			 */
297 			if (cp->a2->type == AT_LINE &&
298 			    linenum >= cp->a2->u.l)
299 				lastaddr = 1;
300 			else
301 				cp->inrange = 1;
302 			r = 1;
303 		} else
304 			r = 0;
305 	else
306 		r = MATCH(cp->a1);
307 	return (cp->nonsel ? ! r : r);
308 }
309 
310 /*
311  * substitute --
312  *	Do substitutions in the pattern space.  Currently, we build a
313  *	copy of the new pattern space in the substitute space structure
314  *	and then swap them.
315  */
316 static int
317 substitute(struct s_command *cp)
318 {
319 	SPACE tspace;
320 	regex_t *re;
321 	regoff_t re_off, slen;
322 	int lastempty, n;
323 	char *s;
324 
325 	s = ps;
326 	re = cp->u.s->re;
327 	if (re == NULL) {
328 		if (defpreg != NULL && cp->u.s->maxbref > defpreg->re_nsub) {
329 			linenum = cp->u.s->linenum;
330 			errx(1, "%lu: %s: \\%d not defined in the RE",
331 					linenum, fname, cp->u.s->maxbref);
332 		}
333 	}
334 	if (!regexec_e(re, s, 0, 0, psl))
335 		return (0);
336 
337 	SS.len = 0;				/* Clean substitute space. */
338 	slen = psl;
339 	n = cp->u.s->n;
340 	lastempty = 1;
341 
342 	switch (n) {
343 	case 0:					/* Global */
344 		do {
345 			if (lastempty || match[0].rm_so != match[0].rm_eo) {
346 				/* Locate start of replaced string. */
347 				re_off = match[0].rm_so;
348 				/* Copy leading retained string. */
349 				cspace(&SS, s, re_off, APPEND);
350 				/* Add in regular expression. */
351 				regsub(&SS, s, cp->u.s->new);
352 			}
353 
354 			/* Move past this match. */
355 			if (match[0].rm_so != match[0].rm_eo) {
356 				s += match[0].rm_eo;
357 				slen -= match[0].rm_eo;
358 				lastempty = 0;
359 			} else {
360 				if (match[0].rm_so < slen)
361 					cspace(&SS, s + match[0].rm_so, 1,
362 					    APPEND);
363 				s += match[0].rm_so + 1;
364 				slen -= match[0].rm_so + 1;
365 				lastempty = 1;
366 			}
367 		} while (slen >= 0 && regexec_e(re, s, REG_NOTBOL, 0, slen));
368 		/* Copy trailing retained string. */
369 		if (slen > 0)
370 			cspace(&SS, s, slen, APPEND);
371 		break;
372 	default:				/* Nth occurrence */
373 		while (--n) {
374 			if (match[0].rm_eo == match[0].rm_so)
375 				match[0].rm_eo = match[0].rm_so + 1;
376 			s += match[0].rm_eo;
377 			slen -= match[0].rm_eo;
378 			if (slen < 0)
379 				return (0);
380 			if (!regexec_e(re, s, REG_NOTBOL, 0, slen))
381 				return (0);
382 		}
383 		/* FALLTHROUGH */
384 	case 1:					/* 1st occurrence */
385 		/* Locate start of replaced string. */
386 		re_off = match[0].rm_so + (s - ps);
387 		/* Copy leading retained string. */
388 		cspace(&SS, ps, re_off, APPEND);
389 		/* Add in regular expression. */
390 		regsub(&SS, s, cp->u.s->new);
391 		/* Copy trailing retained string. */
392 		s += match[0].rm_eo;
393 		slen -= match[0].rm_eo;
394 		cspace(&SS, s, slen, APPEND);
395 		break;
396 	}
397 
398 	/*
399 	 * Swap the substitute space and the pattern space, and make sure
400 	 * that any leftover pointers into stdio memory get lost.
401 	 */
402 	tspace = PS;
403 	PS = SS;
404 	SS = tspace;
405 	SS.space = SS.back;
406 
407 	/* Handle the 'p' flag. */
408 	if (cp->u.s->p)
409 		OUT(ps)
410 
411 	/* Handle the 'w' flag. */
412 	if (cp->u.s->wfile && !pd) {
413 		if (cp->u.s->wfd == -1 && (cp->u.s->wfd = open(cp->u.s->wfile,
414 		    O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1)
415 			err(1, "%s", cp->u.s->wfile);
416 		if (write(cp->u.s->wfd, ps, psl) != psl ||
417 		    write(cp->u.s->wfd, "\n", 1) != 1)
418 			err(1, "%s", cp->u.s->wfile);
419 	}
420 	return (1);
421 }
422 
423 /*
424  * do_tr --
425  *	Perform translation ('y' command) in the pattern space.
426  */
427 static void
428 do_tr(struct s_tr *y)
429 {
430 	SPACE tmp;
431 	char c, *p;
432 	size_t clen, left;
433 	int i;
434 
435 	if (MB_CUR_MAX == 1) {
436 		/*
437 		 * Single-byte encoding: perform in-place translation
438 		 * of the pattern space.
439 		 */
440 		for (p = ps; p < &ps[psl]; p++)
441 			*p = y->bytetab[(u_char)*p];
442 	} else {
443 		/*
444 		 * Multi-byte encoding: perform translation into the
445 		 * translation space, then swap the translation and
446 		 * pattern spaces.
447 		 */
448 		/* Clean translation space. */
449 		YS.len = 0;
450 		for (p = ps, left = psl; left > 0; p += clen, left -= clen) {
451 			if ((c = y->bytetab[(u_char)*p]) != '\0') {
452 				cspace(&YS, &c, 1, APPEND);
453 				clen = 1;
454 				continue;
455 			}
456 			for (i = 0; i < y->nmultis; i++)
457 				if (left >= y->multis[i].fromlen &&
458 				    memcmp(p, y->multis[i].from,
459 				    y->multis[i].fromlen) == 0)
460 					break;
461 			if (i < y->nmultis) {
462 				cspace(&YS, y->multis[i].to,
463 				    y->multis[i].tolen, APPEND);
464 				clen = y->multis[i].fromlen;
465 			} else {
466 				cspace(&YS, p, 1, APPEND);
467 				clen = 1;
468 			}
469 		}
470 		/* Swap the translation space and the pattern space. */
471 		tmp = PS;
472 		PS = YS;
473 		YS = tmp;
474 		YS.space = YS.back;
475 	}
476 }
477 
478 /*
479  * Flush append requests.  Always called before reading a line,
480  * therefore it also resets the substitution done (sdone) flag.
481  */
482 static void
483 flush_appends(void)
484 {
485 	FILE *f;
486 	int count, i;
487 	char buf[8 * 1024];
488 
489 	for (i = 0; i < appendx; i++)
490 		switch (appends[i].type) {
491 		case AP_STRING:
492 			fwrite(appends[i].s, sizeof(char), appends[i].len,
493 			    outfile);
494 			break;
495 		case AP_FILE:
496 			/*
497 			 * Read files probably shouldn't be cached.  Since
498 			 * it's not an error to read a non-existent file,
499 			 * it's possible that another program is interacting
500 			 * with the sed script through the filesystem.  It
501 			 * would be truly bizarre, but possible.  It's probably
502 			 * not that big a performance win, anyhow.
503 			 */
504 			if ((f = fopen(appends[i].s, "r")) == NULL)
505 				break;
506 			while ((count = fread(buf, sizeof(char), sizeof(buf), f)))
507 				(void)fwrite(buf, sizeof(char), count, outfile);
508 			(void)fclose(f);
509 			break;
510 		}
511 	if (ferror(outfile))
512 		errx(1, "%s: %s", outfname, strerror(errno ? errno : EIO));
513 	appendx = sdone = 0;
514 }
515 
516 static void
517 lputs(char *s, size_t len)
518 {
519 	static const char escapes[] = "\\\a\b\f\r\t\v";
520 	int c, col, width;
521 	char *p;
522 	struct winsize win;
523 	static int termwidth = -1;
524 	size_t clen, i;
525 	wchar_t wc;
526 	mbstate_t mbs;
527 
528 	if (outfile != stdout)
529 		termwidth = 60;
530 	if (termwidth == -1) {
531 		if ((p = getenv("COLUMNS")) && *p != '\0')
532 			termwidth = atoi(p);
533 		else if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 &&
534 		    win.ws_col > 0)
535 			termwidth = win.ws_col;
536 		else
537 			termwidth = 60;
538 	}
539 
540 	memset(&mbs, 0, sizeof(mbs));
541 	col = 0;
542 	while (len != 0) {
543 		clen = mbrtowc(&wc, s, len, &mbs);
544 		if (clen == 0)
545 			clen = 1;
546 		if (clen == (size_t)-1 || clen == (size_t)-2) {
547 			wc = (unsigned char)*s;
548 			clen = 1;
549 			memset(&mbs, 0, sizeof(mbs));
550 		}
551 		if (wc == '\n') {
552 			if (col + 1 >= termwidth)
553 				fprintf(outfile, "\\\n");
554 			fputc('$', outfile);
555 			fputc('\n', outfile);
556 			col = 0;
557 		} else if (iswprint(wc)) {
558 			width = wcwidth(wc);
559 			if (col + width >= termwidth) {
560 				fprintf(outfile, "\\\n");
561 				col = 0;
562 			}
563 			fwrite(s, 1, clen, outfile);
564 			col += width;
565 		} else if (wc != L'\0' && (c = wctob(wc)) != EOF &&
566 		    (p = strchr(escapes, c)) != NULL) {
567 			if (col + 2 >= termwidth) {
568 				fprintf(outfile, "\\\n");
569 				col = 0;
570 			}
571 			fprintf(outfile, "\\%c", "\\abfrtv"[p - escapes]);
572 			col += 2;
573 		} else {
574 			if (col + 4 * clen >= termwidth) {
575 				fprintf(outfile, "\\\n");
576 				col = 0;
577 			}
578 			for (i = 0; i < clen; i++)
579 				fprintf(outfile, "\\%03o",
580 				    (int)(unsigned char)s[i]);
581 			col += 4 * clen;
582 		}
583 		s += clen;
584 		len -= clen;
585 	}
586 	if (col + 1 >= termwidth)
587 		fprintf(outfile, "\\\n");
588 	(void)fputc('$', outfile);
589 	(void)fputc('\n', outfile);
590 	if (ferror(outfile))
591 		errx(1, "%s: %s", outfname, strerror(errno ? errno : EIO));
592 }
593 
594 static __inline int
595 regexec_e(regex_t *preg, const char *string, int eflags, int nomatch,
596 	size_t slen)
597 {
598 	int eval;
599 
600 	if (preg == NULL) {
601 		if (defpreg == NULL)
602 			errx(1, "first RE may not be empty");
603 	} else
604 		defpreg = preg;
605 
606 	/* Set anchors */
607 	match[0].rm_so = 0;
608 	match[0].rm_eo = slen;
609 
610 	eval = regexec(defpreg, string,
611 	    nomatch ? 0 : maxnsub + 1, match, eflags | REG_STARTEND);
612 	switch(eval) {
613 	case 0:
614 		return (1);
615 	case REG_NOMATCH:
616 		return (0);
617 	}
618 	errx(1, "RE error: %s", strregerror(eval, defpreg));
619 	/* NOTREACHED */
620 }
621 
622 /*
623  * regsub - perform substitutions after a regexp match
624  * Based on a routine by Henry Spencer
625  */
626 static void
627 regsub(SPACE *sp, char *string, char *src)
628 {
629 	int len, no;
630 	char c, *dst;
631 
632 #define	NEEDSP(reqlen)							\
633 	/* XXX What is the +1 for? */					\
634 	if (sp->len + (reqlen) + 1 >= sp->blen) {			\
635 		sp->blen += (reqlen) + 1024;				\
636 		if ((sp->space = sp->back = realloc(sp->back, sp->blen)) \
637 		    == NULL)						\
638 			err(1, "realloc");				\
639 		dst = sp->space + sp->len;				\
640 	}
641 
642 	dst = sp->space + sp->len;
643 	while ((c = *src++) != '\0') {
644 		if (c == '&')
645 			no = 0;
646 		else if (c == '\\' && isdigit((unsigned char)*src))
647 			no = *src++ - '0';
648 		else
649 			no = -1;
650 		if (no < 0) {		/* Ordinary character. */
651 			if (c == '\\' && (*src == '\\' || *src == '&'))
652 				c = *src++;
653 			NEEDSP(1);
654 			*dst++ = c;
655 			++sp->len;
656 		} else if (match[no].rm_so != -1 && match[no].rm_eo != -1) {
657 			len = match[no].rm_eo - match[no].rm_so;
658 			NEEDSP(len);
659 			memmove(dst, string + match[no].rm_so, len);
660 			dst += len;
661 			sp->len += len;
662 		}
663 	}
664 	NEEDSP(1);
665 	*dst = '\0';
666 }
667 
668 /*
669  * aspace --
670  *	Append the source space to the destination space, allocating new
671  *	space as necessary.
672  */
673 void
674 cspace(SPACE *sp, const char *p, size_t len, enum e_spflag spflag)
675 {
676 	size_t tlen;
677 
678 	/* Make sure SPACE has enough memory and ramp up quickly. */
679 	tlen = sp->len + len + 1;
680 	if (tlen > sp->blen) {
681 		sp->blen = tlen + 1024;
682 		if ((sp->space = sp->back = realloc(sp->back, sp->blen)) ==
683 		    NULL)
684 			err(1, "realloc");
685 	}
686 
687 	if (spflag == REPLACE)
688 		sp->len = 0;
689 
690 	memmove(sp->space + sp->len, p, len);
691 
692 	sp->space[sp->len += len] = '\0';
693 }
694 
695 /*
696  * Close all cached opened files and report any errors
697  */
698 void
699 cfclose(struct s_command *cp, struct s_command *end)
700 {
701 
702 	for (; cp != end; cp = cp->next)
703 		switch(cp->code) {
704 		case 's':
705 			if (cp->u.s->wfd != -1 && close(cp->u.s->wfd))
706 				err(1, "%s", cp->u.s->wfile);
707 			cp->u.s->wfd = -1;
708 			break;
709 		case 'w':
710 			if (cp->u.fd != -1 && close(cp->u.fd))
711 				err(1, "%s", cp->t);
712 			cp->u.fd = -1;
713 			break;
714 		case '{':
715 			cfclose(cp->u.c, cp->next);
716 			break;
717 		}
718 }
719