xref: /netbsd-src/bin/csh/dol.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*-
2  * Copyright (c) 1980, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
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 #ifndef lint
35 /*static char sccsid[] = "from: @(#)dol.c	8.1 (Berkeley) 5/31/93";*/
36 static char *rcsid = "$Id: dol.c,v 1.6 1994/09/23 11:16:33 mycroft Exp $";
37 #endif /* not lint */
38 
39 #include <sys/types.h>
40 #include <fcntl.h>
41 #include <errno.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 #if __STDC__
46 # include <stdarg.h>
47 #else
48 # include <varargs.h>
49 #endif
50 
51 #include "csh.h"
52 #include "extern.h"
53 
54 /*
55  * These routines perform variable substitution and quoting via ' and ".
56  * To this point these constructs have been preserved in the divided
57  * input words.  Here we expand variables and turn quoting via ' and " into
58  * QUOTE bits on characters (which prevent further interpretation).
59  * If the `:q' modifier was applied during history expansion, then
60  * some QUOTEing may have occurred already, so we dont "trim()" here.
61  */
62 
63 static int Dpeekc, Dpeekrd;	/* Peeks for DgetC and Dreadc */
64 static Char *Dcp, **Dvp;	/* Input vector for Dreadc */
65 
66 #define	DEOF	-1
67 
68 #define	unDgetC(c)	Dpeekc = c
69 
70 #define QUOTES		(_QF|_QB|_ESC)	/* \ ' " ` */
71 
72 /*
73  * The following variables give the information about the current
74  * $ expansion, recording the current word position, the remaining
75  * words within this expansion, the count of remaining words, and the
76  * information about any : modifier which is being applied.
77  */
78 #define MAXWLEN (BUFSIZ - 4)
79 #define MAXMOD MAXWLEN		/* This cannot overflow	*/
80 static Char *dolp;		/* Remaining chars from this word */
81 static Char **dolnxt;		/* Further words */
82 static int dolcnt;		/* Count of further words */
83 static Char dolmod[MAXMOD];	/* : modifier character */
84 static int dolnmod;		/* Number of modifiers */
85 static int dolmcnt;		/* :gx -> 10000, else 1 */
86 static int dolwcnt;		/* :wx -> 10000, else 1 */
87 
88 static void	 Dfix2 __P((Char **));
89 static Char	*Dpack __P((Char *, Char *));
90 static int	 Dword __P((void));
91 static void	 dolerror __P((Char *));
92 static int	 DgetC __P((int));
93 static void	 Dgetdol __P((void));
94 static void	 fixDolMod __P((void));
95 static void	 setDolp __P((Char *));
96 static void	 unDredc __P((int));
97 static int	 Dredc __P((void));
98 static void	 Dtestq __P((int));
99 
100 
101 /*
102  * Fix up the $ expansions and quotations in the
103  * argument list to command t.
104  */
105 void
106 Dfix(t)
107     register struct command *t;
108 {
109     register Char **pp;
110     register Char *p;
111 
112     if (noexec)
113 	return;
114     /* Note that t_dcom isn't trimmed thus !...:q's aren't lost */
115     for (pp = t->t_dcom; (p = *pp++) != NULL;)
116 	for (; *p; p++) {
117 	    if (cmap(*p, _DOL | QUOTES)) {	/* $, \, ', ", ` */
118 		Dfix2(t->t_dcom);	/* found one */
119 		blkfree(t->t_dcom);
120 		t->t_dcom = gargv;
121 		gargv = 0;
122 		return;
123 	    }
124 	}
125 }
126 
127 /*
128  * $ substitute one word, for i/o redirection
129  */
130 Char   *
131 Dfix1(cp)
132     register Char *cp;
133 {
134     Char   *Dv[2];
135 
136     if (noexec)
137 	return (0);
138     Dv[0] = cp;
139     Dv[1] = NULL;
140     Dfix2(Dv);
141     if (gargc != 1) {
142 	setname(vis_str(cp));
143 	stderror(ERR_NAME | ERR_AMBIG);
144     }
145     cp = Strsave(gargv[0]);
146     blkfree(gargv), gargv = 0;
147     return (cp);
148 }
149 
150 /*
151  * Subroutine to do actual fixing after state initialization.
152  */
153 static void
154 Dfix2(v)
155     Char  **v;
156 {
157     ginit();			/* Initialize glob's area pointers */
158     Dvp = v;
159     Dcp = STRNULL;		/* Setup input vector for Dreadc */
160     unDgetC(0);
161     unDredc(0);			/* Clear out any old peeks (at error) */
162     dolp = 0;
163     dolcnt = 0;			/* Clear out residual $ expands (...) */
164     while (Dword())
165 	continue;
166 }
167 
168 /*
169  * Pack up more characters in this word
170  */
171 static Char *
172 Dpack(wbuf, wp)
173     Char   *wbuf, *wp;
174 {
175     register int c;
176     register int i = MAXWLEN - (wp - wbuf);
177 
178     for (;;) {
179 	c = DgetC(DODOL);
180 	if (c == '\\') {
181 	    c = DgetC(0);
182 	    if (c == DEOF) {
183 		unDredc(c);
184 		*wp = 0;
185 		Gcat(STRNULL, wbuf);
186 		return (NULL);
187 	    }
188 	    if (c == '\n')
189 		c = ' ';
190 	    else
191 		c |= QUOTE;
192 	}
193 	if (c == DEOF) {
194 	    unDredc(c);
195 	    *wp = 0;
196 	    Gcat(STRNULL, wbuf);
197 	    return (NULL);
198 	}
199 	if (cmap(c, _SP | _NL | _QF | _QB)) {	/* sp \t\n'"` */
200 	    unDgetC(c);
201 	    if (cmap(c, QUOTES))
202 		return (wp);
203 	    *wp++ = 0;
204 	    Gcat(STRNULL, wbuf);
205 	    return (NULL);
206 	}
207 	if (--i <= 0)
208 	    stderror(ERR_WTOOLONG);
209 	*wp++ = c;
210     }
211 }
212 
213 /*
214  * Get a word.  This routine is analogous to the routine
215  * word() in sh.lex.c for the main lexical input.  One difference
216  * here is that we don't get a newline to terminate our expansion.
217  * Rather, DgetC will return a DEOF when we hit the end-of-input.
218  */
219 static int
220 Dword()
221 {
222     register int c, c1;
223     Char    wbuf[BUFSIZ];
224     register Char *wp = wbuf;
225     register int i = MAXWLEN;
226     register bool dolflg;
227     bool    sofar = 0, done = 0;
228 
229     while (!done) {
230 	done = 1;
231 	c = DgetC(DODOL);
232 	switch (c) {
233 
234 	case DEOF:
235 	    if (sofar == 0)
236 		return (0);
237 	    /* finish this word and catch the code above the next time */
238 	    unDredc(c);
239 	    /* fall into ... */
240 
241 	case '\n':
242 	    *wp = 0;
243 	    Gcat(STRNULL, wbuf);
244 	    return (1);
245 
246 	case ' ':
247 	case '\t':
248 	    done = 0;
249 	    break;
250 
251 	case '`':
252 	    /* We preserve ` quotations which are done yet later */
253 	    *wp++ = c, --i;
254 	case '\'':
255 	case '"':
256 	    /*
257 	     * Note that DgetC never returns a QUOTES character from an
258 	     * expansion, so only true input quotes will get us here or out.
259 	     */
260 	    c1 = c;
261 	    dolflg = c1 == '"' ? DODOL : 0;
262 	    for (;;) {
263 		c = DgetC(dolflg);
264 		if (c == c1)
265 		    break;
266 		if (c == '\n' || c == DEOF)
267 		    stderror(ERR_UNMATCHED, c1);
268 		if ((c & (QUOTE | TRIM)) == ('\n' | QUOTE))
269 		    --wp, ++i;
270 		if (--i <= 0)
271 		    stderror(ERR_WTOOLONG);
272 		switch (c1) {
273 
274 		case '"':
275 		    /*
276 		     * Leave any `s alone for later. Other chars are all
277 		     * quoted, thus `...` can tell it was within "...".
278 		     */
279 		    *wp++ = c == '`' ? '`' : c | QUOTE;
280 		    break;
281 
282 		case '\'':
283 		    /* Prevent all further interpretation */
284 		    *wp++ = c | QUOTE;
285 		    break;
286 
287 		case '`':
288 		    /* Leave all text alone for later */
289 		    *wp++ = c;
290 		    break;
291 
292 		default:
293 		    break;
294 		}
295 	    }
296 	    if (c1 == '`')
297 		*wp++ = '`' /* i--; eliminated */;
298 	    sofar = 1;
299 	    if ((wp = Dpack(wbuf, wp)) == NULL)
300 		return (1);
301 	    else {
302 		i = MAXWLEN - (wp - wbuf);
303 		done = 0;
304 	    }
305 	    break;
306 
307 	case '\\':
308 	    c = DgetC(0);	/* No $ subst! */
309 	    if (c == '\n' || c == DEOF) {
310 		done = 0;
311 		break;
312 	    }
313 	    c |= QUOTE;
314 	    break;
315 
316 	default:
317 	    break;
318 	}
319 	if (done) {
320 	    unDgetC(c);
321 	    sofar = 1;
322 	    if ((wp = Dpack(wbuf, wp)) == NULL)
323 		return (1);
324 	    else {
325 		i = MAXWLEN - (wp - wbuf);
326 		done = 0;
327 	    }
328 	}
329     }
330     /* Really NOTREACHED */
331     return (0);
332 }
333 
334 
335 /*
336  * Get a character, performing $ substitution unless flag is 0.
337  * Any QUOTES character which is returned from a $ expansion is
338  * QUOTEd so that it will not be recognized above.
339  */
340 static int
341 DgetC(flag)
342     register int flag;
343 {
344     register int c;
345 
346 top:
347     if ((c = Dpeekc) != '\0') {
348 	Dpeekc = 0;
349 	return (c);
350     }
351     if (lap) {
352 	c = *lap++ & (QUOTE | TRIM);
353 	if (c == 0) {
354 	    lap = 0;
355 	    goto top;
356 	}
357 quotspec:
358 	if (cmap(c, QUOTES))
359 	    return (c | QUOTE);
360 	return (c);
361     }
362     if (dolp) {
363 	if ((c = *dolp++ & (QUOTE | TRIM)) != '\0')
364 	    goto quotspec;
365 	if (dolcnt > 0) {
366 	    setDolp(*dolnxt++);
367 	    --dolcnt;
368 	    return (' ');
369 	}
370 	dolp = 0;
371     }
372     if (dolcnt > 0) {
373 	setDolp(*dolnxt++);
374 	--dolcnt;
375 	goto top;
376     }
377     c = Dredc();
378     if (c == '$' && flag) {
379 	Dgetdol();
380 	goto top;
381     }
382     return (c);
383 }
384 
385 static Char *nulvec[] = {0};
386 static struct varent nulargv = {nulvec, STRargv, { NULL, NULL, NULL }, 0};
387 
388 static void
389 dolerror(s)
390     Char   *s;
391 {
392     setname(vis_str(s));
393     stderror(ERR_NAME | ERR_RANGE);
394 }
395 
396 /*
397  * Handle the multitudinous $ expansion forms.
398  * Ugh.
399  */
400 static void
401 Dgetdol()
402 {
403     register Char *np;
404     register struct varent *vp = NULL;
405     Char    name[4 * MAXVARLEN + 1];
406     int     c, sc;
407     int     subscr = 0, lwb = 1, upb = 0;
408     bool    dimen = 0, bitset = 0;
409     char    tnp;
410     Char    wbuf[BUFSIZ];
411     static Char *dolbang = NULL;
412 
413     dolnmod = dolmcnt = dolwcnt = 0;
414     c = sc = DgetC(0);
415     if (c == '{')
416 	c = DgetC(0);		/* sc is { to take } later */
417     if ((c & TRIM) == '#')
418 	dimen++, c = DgetC(0);	/* $# takes dimension */
419     else if (c == '?')
420 	bitset++, c = DgetC(0);	/* $? tests existence */
421     switch (c) {
422 
423     case '!':
424 	if (dimen || bitset)
425 	    stderror(ERR_SYNTAX);
426 	if (backpid != 0) {
427 	    if (dolbang)
428 		xfree((ptr_t) dolbang);
429 	    setDolp(dolbang = putn(backpid));
430 	}
431 	goto eatbrac;
432 
433     case '$':
434 	if (dimen || bitset)
435 	    stderror(ERR_SYNTAX);
436 	setDolp(doldol);
437 	goto eatbrac;
438 
439     case '<' | QUOTE:
440 	if (bitset)
441 	    stderror(ERR_NOTALLOWED, "$?<");
442 	if (dimen)
443 	    stderror(ERR_NOTALLOWED, "$?#");
444 	for (np = wbuf; read(OLDSTD, &tnp, 1) == 1; np++) {
445 	    *np = (unsigned char) tnp;
446 	    if (np >= &wbuf[BUFSIZ - 1])
447 		stderror(ERR_LTOOLONG);
448 	    if (tnp == '\n')
449 		break;
450 	}
451 	*np = 0;
452 	/*
453 	 * KLUDGE: dolmod is set here because it will cause setDolp to call
454 	 * domod and thus to copy wbuf. Otherwise setDolp would use it
455 	 * directly. If we saved it ourselves, no one would know when to free
456 	 * it. The actual function of the 'q' causes filename expansion not to
457 	 * be done on the interpolated value.
458 	 */
459 	dolmod[dolnmod++] = 'q';
460 	dolmcnt = 10000;
461 	setDolp(wbuf);
462 	goto eatbrac;
463 
464     case DEOF:
465     case '\n':
466 	stderror(ERR_SYNTAX);
467 	/* NOTREACHED */
468 	break;
469 
470     case '*':
471 	(void) Strcpy(name, STRargv);
472 	vp = adrof(STRargv);
473 	subscr = -1;		/* Prevent eating [...] */
474 	break;
475 
476     default:
477 	np = name;
478 	if (Isdigit(c)) {
479 	    if (dimen)
480 		stderror(ERR_NOTALLOWED, "$#<num>");
481 	    subscr = 0;
482 	    do {
483 		subscr = subscr * 10 + c - '0';
484 		c = DgetC(0);
485 	    } while (Isdigit(c));
486 	    unDredc(c);
487 	    if (subscr < 0) {
488 		dolerror(vp->v_name);
489 		return;
490 	    }
491 	    if (subscr == 0) {
492 		if (bitset) {
493 		    dolp = ffile ? STR1 : STR0;
494 		    goto eatbrac;
495 		}
496 		if (ffile == 0)
497 		    stderror(ERR_DOLZERO);
498 		fixDolMod();
499 		setDolp(ffile);
500 		goto eatbrac;
501 	    }
502 	    if (bitset)
503 		stderror(ERR_DOLQUEST);
504 	    vp = adrof(STRargv);
505 	    if (vp == 0) {
506 		vp = &nulargv;
507 		goto eatmod;
508 	    }
509 	    break;
510 	}
511 	if (!alnum(c))
512 	    stderror(ERR_VARALNUM);
513 	for (;;) {
514 	    *np++ = c;
515 	    c = DgetC(0);
516 	    if (!alnum(c))
517 		break;
518 	    if (np >= &name[MAXVARLEN])
519 		stderror(ERR_VARTOOLONG);
520 	}
521 	*np++ = 0;
522 	unDredc(c);
523 	vp = adrof(name);
524     }
525     if (bitset) {
526 	dolp = (vp || getenv(short2str(name))) ? STR1 : STR0;
527 	goto eatbrac;
528     }
529     if (vp == 0) {
530 	np = str2short(getenv(short2str(name)));
531 	if (np) {
532 	    fixDolMod();
533 	    setDolp(np);
534 	    goto eatbrac;
535 	}
536 	udvar(name);
537 	/* NOTREACHED */
538     }
539     c = DgetC(0);
540     upb = blklen(vp->vec);
541     if (dimen == 0 && subscr == 0 && c == '[') {
542 	np = name;
543 	for (;;) {
544 	    c = DgetC(DODOL);	/* Allow $ expand within [ ] */
545 	    if (c == ']')
546 		break;
547 	    if (c == '\n' || c == DEOF)
548 		stderror(ERR_INCBR);
549 	    if (np >= &name[sizeof(name) / sizeof(Char) - 2])
550 		stderror(ERR_VARTOOLONG);
551 	    *np++ = c;
552 	}
553 	*np = 0, np = name;
554 	if (dolp || dolcnt)	/* $ exp must end before ] */
555 	    stderror(ERR_EXPORD);
556 	if (!*np)
557 	    stderror(ERR_SYNTAX);
558 	if (Isdigit(*np)) {
559 	    int     i;
560 
561 	    for (i = 0; Isdigit(*np); i = i * 10 + *np++ - '0')
562 		continue;
563 	    if ((i < 0 || i > upb) && !any("-*", *np)) {
564 		dolerror(vp->v_name);
565 		return;
566 	    }
567 	    lwb = i;
568 	    if (!*np)
569 		upb = lwb, np = STRstar;
570 	}
571 	if (*np == '*')
572 	    np++;
573 	else if (*np != '-')
574 	    stderror(ERR_MISSING, '-');
575 	else {
576 	    register int i = upb;
577 
578 	    np++;
579 	    if (Isdigit(*np)) {
580 		i = 0;
581 		while (Isdigit(*np))
582 		    i = i * 10 + *np++ - '0';
583 		if (i < 0 || i > upb) {
584 		    dolerror(vp->v_name);
585 		    return;
586 		}
587 	    }
588 	    if (i < lwb)
589 		upb = lwb - 1;
590 	    else
591 		upb = i;
592 	}
593 	if (lwb == 0) {
594 	    if (upb != 0) {
595 		dolerror(vp->v_name);
596 		return;
597 	    }
598 	    upb = -1;
599 	}
600 	if (*np)
601 	    stderror(ERR_SYNTAX);
602     }
603     else {
604 	if (subscr > 0)
605 	    if (subscr > upb)
606 		lwb = 1, upb = 0;
607 	    else
608 		lwb = upb = subscr;
609 	unDredc(c);
610     }
611     if (dimen) {
612 	Char   *cp = putn(upb - lwb + 1);
613 
614 	addla(cp);
615 	xfree((ptr_t) cp);
616     }
617     else {
618 eatmod:
619 	fixDolMod();
620 	dolnxt = &vp->vec[lwb - 1];
621 	dolcnt = upb - lwb + 1;
622     }
623 eatbrac:
624     if (sc == '{') {
625 	c = Dredc();
626 	if (c != '}')
627 	    stderror(ERR_MISSING, '}');
628     }
629 }
630 
631 static void
632 fixDolMod()
633 {
634     register int c;
635 
636     c = DgetC(0);
637     if (c == ':') {
638 	do {
639 	    c = DgetC(0), dolmcnt = 1, dolwcnt = 1;
640 	    if (c == 'g' || c == 'a') {
641 		if (c == 'g')
642 		    dolmcnt = 10000;
643 		else
644 		    dolwcnt = 10000;
645 		c = DgetC(0);
646 	    }
647 	    if ((c == 'g' && dolmcnt != 10000) ||
648 		(c == 'a' && dolwcnt != 10000)) {
649 		if (c == 'g')
650 		    dolmcnt = 10000;
651 		else
652 		    dolwcnt = 10000;
653 		c = DgetC(0);
654 	    }
655 
656 	    if (c == 's') {	/* [eichin:19910926.0755EST] */
657 		int delimcnt = 2;
658 		int delim = DgetC(0);
659 		dolmod[dolnmod++] = c;
660 		dolmod[dolnmod++] = delim;
661 
662 		if (!delim || letter(delim)
663 		    || Isdigit(delim) || any(" \t\n", delim)) {
664 		    seterror(ERR_BADSUBST);
665 		    break;
666 		}
667 		while ((c = DgetC(0)) != (-1)) {
668 		    dolmod[dolnmod++] = c;
669 		    if(c == delim) delimcnt--;
670 		    if(!delimcnt) break;
671 		}
672 		if(delimcnt) {
673 		    seterror(ERR_BADSUBST);
674 		    break;
675 		}
676 		continue;
677 	    }
678 	    if (!any("htrqxes", c))
679 		stderror(ERR_BADMOD, c);
680 	    dolmod[dolnmod++] = c;
681 	    if (c == 'q')
682 		dolmcnt = 10000;
683 	}
684 	while ((c = DgetC(0)) == ':');
685 	unDredc(c);
686     }
687     else
688 	unDredc(c);
689 }
690 
691 static void
692 setDolp(cp)
693     register Char *cp;
694 {
695     register Char *dp;
696     int i;
697 
698     if (dolnmod == 0 || dolmcnt == 0) {
699 	dolp = cp;
700 	return;
701     }
702     dp = cp = Strsave(cp);
703     for (i = 0; i < dolnmod; i++) {
704 	/* handle s// [eichin:19910926.0510EST] */
705 	if(dolmod[i] == 's') {
706 	    int delim;
707 	    Char *lhsub, *rhsub, *np;
708 	    size_t lhlen = 0, rhlen = 0;
709 	    int didmod = 0;
710 
711 	    delim = dolmod[++i];
712 	    if (!delim || letter(delim)
713 		|| Isdigit(delim) || any(" \t\n", delim)) {
714 		seterror(ERR_BADSUBST);
715 		break;
716 	    }
717 	    lhsub = &dolmod[++i];
718 	    while(dolmod[i] != delim && dolmod[++i]) {
719 		lhlen++;
720 	    }
721 	    dolmod[i] = 0;
722 	    rhsub = &dolmod[++i];
723 	    while(dolmod[i] != delim && dolmod[++i]) {
724 		rhlen++;
725 	    }
726 	    dolmod[i] = 0;
727 
728 	    do {
729 		dp = Strstr(cp, lhsub);
730 		if (dp) {
731 		    np = (Char *) xmalloc((size_t)
732 					  ((Strlen(cp) + 1 - lhlen + rhlen) *
733 					  sizeof(Char)));
734 		    (void) Strncpy(np, cp, dp - cp);
735 		    (void) Strcpy(np + (dp - cp), rhsub);
736 		    (void) Strcpy(np + (dp - cp) + rhlen, dp + lhlen);
737 
738 		    xfree((ptr_t) cp);
739 		    dp = cp = np;
740 		    didmod = 1;
741 		} else {
742 		    /* should this do a seterror? */
743 		    break;
744 		}
745 	    }
746 	    while (dolwcnt == 10000);
747 	    /*
748 	     * restore dolmod for additional words
749 	     */
750 	    dolmod[i] = rhsub[-1] = delim;
751 	    if (didmod)
752 		dolmcnt--;
753 	    else
754 		break;
755         } else {
756 	    int didmod = 0;
757 
758 	    do {
759 		if ((dp = domod(cp, dolmod[i]))) {
760 		    didmod = 1;
761 		    if (Strcmp(cp, dp) == 0) {
762 			xfree((ptr_t) cp);
763 			cp = dp;
764 			break;
765 		    }
766 		    else {
767 			xfree((ptr_t) cp);
768 			cp = dp;
769 		    }
770 		}
771 		else
772 		    break;
773 	    }
774 	    while (dolwcnt == 10000);
775 	    dp = cp;
776 	    if (didmod)
777 		dolmcnt--;
778 	    else
779 		break;
780 	}
781     }
782 
783     if (dp) {
784 	addla(dp);
785 	xfree((ptr_t) dp);
786     }
787     else
788 	addla(cp);
789 
790     dolp = STRNULL;
791     if (seterr)
792 	stderror(ERR_OLD);
793 }
794 
795 static void
796 unDredc(c)
797     int     c;
798 {
799 
800     Dpeekrd = c;
801 }
802 
803 static int
804 Dredc()
805 {
806     register int c;
807 
808     if ((c = Dpeekrd) != '\0') {
809 	Dpeekrd = 0;
810 	return (c);
811     }
812     if (Dcp && (c = *Dcp++))
813 	return (c & (QUOTE | TRIM));
814     if (*Dvp == 0) {
815 	Dcp = 0;
816 	return (DEOF);
817     }
818     Dcp = *Dvp++;
819     return (' ');
820 }
821 
822 static void
823 Dtestq(c)
824     register int c;
825 {
826 
827     if (cmap(c, QUOTES))
828 	gflag = 1;
829 }
830 
831 /*
832  * Form a shell temporary file (in unit 0) from the words
833  * of the shell input up to EOF or a line the same as "term".
834  * Unit 0 should have been closed before this call.
835  */
836 void
837 /*ARGSUSED*/
838 heredoc(term)
839     Char *term;
840 {
841     register int c;
842     Char   *Dv[2];
843     Char    obuf[BUFSIZ], lbuf[BUFSIZ], mbuf[BUFSIZ];
844     int     ocnt, lcnt, mcnt;
845     register Char *lbp, *obp, *mbp;
846     Char  **vp;
847     bool    quoted;
848     char   *tmp;
849 
850     tmp = short2str(shtemp);
851     if (open(tmp, O_RDWR | O_CREAT | O_TRUNC, 0600) < 0)
852 	stderror(ERR_SYSTEM, tmp, strerror(errno));
853     (void) unlink(tmp);		/* 0 0 inode! */
854     Dv[0] = term;
855     Dv[1] = NULL;
856     gflag = 0;
857     trim(Dv);
858     rscan(Dv, Dtestq);
859     quoted = gflag;
860     ocnt = BUFSIZ;
861     obp = obuf;
862     for (;;) {
863 	/*
864 	 * Read up a line
865 	 */
866 	lbp = lbuf;
867 	lcnt = BUFSIZ - 4;
868 	for (;;) {
869 	    c = readc(1);	/* 1 -> Want EOF returns */
870 	    if (c < 0 || c == '\n')
871 		break;
872 	    if ((c &= TRIM) != '\0') {
873 		*lbp++ = c;
874 		if (--lcnt < 0) {
875 		    setname("<<");
876 		    stderror(ERR_NAME | ERR_OVERFLOW);
877 		}
878 	    }
879 	}
880 	*lbp = 0;
881 
882 	/*
883 	 * Check for EOF or compare to terminator -- before expansion
884 	 */
885 	if (c < 0 || eq(lbuf, term)) {
886 	    (void) write(0, short2str(obuf), (size_t) (BUFSIZ - ocnt));
887 	    (void) lseek(0, 0l, L_SET);
888 	    return;
889 	}
890 
891 	/*
892 	 * If term was quoted or -n just pass it on
893 	 */
894 	if (quoted || noexec) {
895 	    *lbp++ = '\n';
896 	    *lbp = 0;
897 	    for (lbp = lbuf; (c = *lbp++) != '\0';) {
898 		*obp++ = c;
899 		if (--ocnt == 0) {
900 		    (void) write(0, short2str(obuf), BUFSIZ);
901 		    obp = obuf;
902 		    ocnt = BUFSIZ;
903 		}
904 	    }
905 	    continue;
906 	}
907 
908 	/*
909 	 * Term wasn't quoted so variable and then command expand the input
910 	 * line
911 	 */
912 	Dcp = lbuf;
913 	Dvp = Dv + 1;
914 	mbp = mbuf;
915 	mcnt = BUFSIZ - 4;
916 	for (;;) {
917 	    c = DgetC(DODOL);
918 	    if (c == DEOF)
919 		break;
920 	    if ((c &= TRIM) == 0)
921 		continue;
922 	    /* \ quotes \ $ ` here */
923 	    if (c == '\\') {
924 		c = DgetC(0);
925 		if (!any("$\\`", c))
926 		    unDgetC(c | QUOTE), c = '\\';
927 		else
928 		    c |= QUOTE;
929 	    }
930 	    *mbp++ = c;
931 	    if (--mcnt == 0) {
932 		setname("<<");
933 		stderror(ERR_NAME | ERR_OVERFLOW);
934 	    }
935 	}
936 	*mbp++ = 0;
937 
938 	/*
939 	 * If any ` in line do command substitution
940 	 */
941 	mbp = mbuf;
942 	if (any(short2str(mbp), '`')) {
943 	    /*
944 	     * 1 arg to dobackp causes substitution to be literal. Words are
945 	     * broken only at newlines so that all blanks and tabs are
946 	     * preserved.  Blank lines (null words) are not discarded.
947 	     */
948 	    vp = dobackp(mbuf, 1);
949 	}
950 	else
951 	    /* Setup trivial vector similar to return of dobackp */
952 	    Dv[0] = mbp, Dv[1] = NULL, vp = Dv;
953 
954 	/*
955 	 * Resurrect the words from the command substitution each separated by
956 	 * a newline.  Note that the last newline of a command substitution
957 	 * will have been discarded, but we put a newline after the last word
958 	 * because this represents the newline after the last input line!
959 	 */
960 	for (; *vp; vp++) {
961 	    for (mbp = *vp; *mbp; mbp++) {
962 		*obp++ = *mbp & TRIM;
963 		if (--ocnt == 0) {
964 		    (void) write(0, short2str(obuf), BUFSIZ);
965 		    obp = obuf;
966 		    ocnt = BUFSIZ;
967 		}
968 	    }
969 	    *obp++ = '\n';
970 	    if (--ocnt == 0) {
971 		(void) write(0, short2str(obuf), BUFSIZ);
972 		obp = obuf;
973 		ocnt = BUFSIZ;
974 	    }
975 	}
976 	if (pargv)
977 	    blkfree(pargv), pargv = 0;
978     }
979 }
980