xref: /freebsd/contrib/tcsh/sh.dol.c (revision 6fd05b64b5b65dd4ba9b86482a0634a5f0b96c29)
1 /* $Header: /src/pub/tcsh/sh.dol.c,v 3.52 2003/03/12 19:14:51 christos Exp $ */
2 /*
3  * sh.dol.c: Variable substitutions
4  */
5 /*-
6  * Copyright (c) 1980, 1991 The Regents of the University of California.
7  * All rights reserved.
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  * 3. 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 #include "sh.h"
34 
35 RCSID("$Id: sh.dol.c,v 3.52 2003/03/12 19:14:51 christos Exp $")
36 
37 /*
38  * C shell
39  */
40 
41 /*
42  * These routines perform variable substitution and quoting via ' and ".
43  * To this point these constructs have been preserved in the divided
44  * input words.  Here we expand variables and turn quoting via ' and " into
45  * QUOTE bits on characters (which prevent further interpretation).
46  * If the `:q' modifier was applied during history expansion, then
47  * some QUOTEing may have occurred already, so we dont "trim()" here.
48  */
49 
50 static int Dpeekc, Dpeekrd;	/* Peeks for DgetC and Dreadc */
51 static Char *Dcp, **Dvp;	/* Input vector for Dreadc */
52 
53 #define	DEOF	-1
54 
55 #define	unDgetC(c)	Dpeekc = c
56 
57 #define QUOTES		(_QF|_QB|_ESC)	/* \ ' " ` */
58 
59 /*
60  * The following variables give the information about the current
61  * $ expansion, recording the current word position, the remaining
62  * words within this expansion, the count of remaining words, and the
63  * information about any : modifier which is being applied.
64  */
65 #define MAXWLEN (BUFSIZE - 4)
66 #ifndef COMPAT
67 #define MAXMOD MAXWLEN		/* This cannot overflow	*/
68 #endif /* COMPAT */
69 static Char *dolp;		/* Remaining chars from this word */
70 static Char **dolnxt;		/* Further words */
71 static int dolcnt;		/* Count of further words */
72 #ifdef COMPAT
73 static Char dolmod;		/* : modifier character */
74 #else
75 static Char dolmod[MAXMOD];	/* : modifier character */
76 static int dolnmod;		/* Number of modifiers */
77 #endif /* COMPAT */
78 static int dolmcnt;		/* :gx -> 10000, else 1 */
79 static int dolwcnt;		/* :ax -> 10000, else 1 */
80 
81 static	void	 Dfix2		__P((Char **));
82 static	Char 	*Dpack		__P((Char *, Char *));
83 static	int	 Dword		__P((void));
84 static	void	 dolerror	__P((Char *));
85 static	int	 DgetC		__P((int));
86 static	void	 Dgetdol	__P((void));
87 static	void	 fixDolMod	__P((void));
88 static	void	 setDolp	__P((Char *));
89 static	void	 unDredc	__P((int));
90 static	int	 Dredc		__P((void));
91 static	void	 Dtestq		__P((int));
92 
93 /*
94  * Fix up the $ expansions and quotations in the
95  * argument list to command t.
96  */
97 void
98 Dfix(t)
99     register struct command *t;
100 {
101     register Char **pp;
102     register Char *p;
103 
104     if (noexec)
105 	return;
106     /* Note that t_dcom isn't trimmed thus !...:q's aren't lost */
107     for (pp = t->t_dcom; (p = *pp++) != NULL;) {
108 	for (; *p; p++) {
109 #ifdef DSPMBYTE
110 	    if (Ismbyte1(*p) && *(p + 1))
111 		p ++;
112 	    else
113 #endif /* DSPMBYTE */
114 	    if (cmap(*p, _DOL | QUOTES)) {	/* $, \, ', ", ` */
115 		Dfix2(t->t_dcom);	/* found one */
116 		blkfree(t->t_dcom);
117 		t->t_dcom = gargv;
118 		gargv = 0;
119 		return;
120 	    }
121 	}
122     }
123 }
124 
125 /*
126  * $ substitute one word, for i/o redirection
127  */
128 Char   *
129 Dfix1(cp)
130     register Char *cp;
131 {
132     Char   *Dv[2];
133 
134     if (noexec)
135 	return (0);
136     Dv[0] = cp;
137     Dv[1] = NULL;
138     Dfix2(Dv);
139     if (gargc != 1) {
140 	setname(short2str(cp));
141 	stderror(ERR_NAME | ERR_AMBIG);
142     }
143     cp = Strsave(gargv[0]);
144     blkfree(gargv), gargv = 0;
145     return (cp);
146 }
147 
148 /*
149  * Subroutine to do actual fixing after state initialization.
150  */
151 static void
152 Dfix2(v)
153     Char  **v;
154 {
155     ginit();			/* Initialize glob's area pointers */
156     Dvp = v;
157     Dcp = STRNULL;		/* Setup input vector for Dreadc */
158     unDgetC(0);
159     unDredc(0);			/* Clear out any old peeks (at error) */
160     dolp = 0;
161     dolcnt = 0;			/* Clear out residual $ expands (...) */
162     while (Dword())
163 	continue;
164 }
165 
166 /*
167  * Pack up more characters in this word
168  */
169 static Char *
170 Dpack(wbuf, wp)
171     Char   *wbuf, *wp;
172 {
173     register int c;
174     register int i = MAXWLEN - (int) (wp - wbuf);
175 #if defined(DSPMBYTE)
176     int mbytepos = 1;
177 #endif /* DSPMBYTE */
178 
179     for (;;) {
180 	c = DgetC(DODOL);
181 #if defined(DSPMBYTE)
182 	if (mbytepos == 1 && Ismbyte1(c)) {
183 	    /* An MB1 byte that may be followed by a MB2 byte */
184 	    mbytepos = 2;
185 	}
186 	else {
187 	    /* check if MB1 byte followed by an MB2 byte */
188 	    if (mbytepos == 2 && Ismbyte2(c)) {
189 		/* MB1 + MB2 make the character */
190 		mbytepos = 1; /* reset */
191 		goto mbyteskip;
192 	    }
193 	    mbytepos = 1; /* reset */
194 	    /* wasn't followed, so the two bytes make two characters */
195 	}
196 #endif /* DSPMBYTE */
197 	if (c == '\\') {
198 	    c = DgetC(0);
199 	    if (c == DEOF) {
200 		unDredc(c);
201 		*wp = 0;
202 		Gcat(STRNULL, wbuf);
203 		return (NULL);
204 	    }
205 	    if (c == '\n')
206 		c = ' ';
207 	    else
208 		c |= QUOTE;
209 	}
210 	if (c == DEOF) {
211 	    unDredc(c);
212 	    *wp = 0;
213 	    Gcat(STRNULL, wbuf);
214 	    return (NULL);
215 	}
216 	if (cmap(c, _SP | _NL | _QF | _QB)) {	/* sp \t\n'"` */
217 	    unDgetC(c);
218 	    if (cmap(c, QUOTES))
219 		return (wp);
220 	    *wp++ = 0;
221 	    Gcat(STRNULL, wbuf);
222 	    return (NULL);
223 	}
224 #if defined(DSPMBYTE)
225 mbyteskip:
226 #endif /* DSPMBYTE */
227 	if (--i <= 0)
228 	    stderror(ERR_WTOOLONG);
229 	*wp++ = (Char) c;
230     }
231 }
232 
233 /*
234  * Get a word.  This routine is analogous to the routine
235  * word() in sh.lex.c for the main lexical input.  One difference
236  * here is that we don't get a newline to terminate our expansion.
237  * Rather, DgetC will return a DEOF when we hit the end-of-input.
238  */
239 static int
240 Dword()
241 {
242     register int c, c1;
243     Char    wbuf[BUFSIZE];
244     register Char *wp = wbuf;
245     register int i = MAXWLEN;
246     register bool dolflg;
247     bool    sofar = 0, done = 0;
248 
249     while (!done) {
250 	done = 1;
251 	c = DgetC(DODOL);
252 	switch (c) {
253 
254 	case DEOF:
255 	    if (sofar == 0)
256 		return (0);
257 	    /* finish this word and catch the code above the next time */
258 	    unDredc(c);
259 	    /*FALLTHROUGH*/
260 
261 	case '\n':
262 	    *wp = 0;
263 	    Gcat(STRNULL, wbuf);
264 	    return (1);
265 
266 	case ' ':
267 	case '\t':
268 	    done = 0;
269 	    break;
270 
271 	case '`':
272 	    /* We preserve ` quotations which are done yet later */
273 	    *wp++ = (Char) c, --i;
274 	    /*FALLTHROUGH*/
275 	case '\'':
276 	case '"':
277 	    /*
278 	     * Note that DgetC never returns a QUOTES character from an
279 	     * expansion, so only true input quotes will get us here or out.
280 	     */
281 	    c1 = c;
282 	    dolflg = c1 == '"' ? DODOL : 0;
283 	    for (;;) {
284 		c = DgetC(dolflg);
285 		if (c == c1)
286 		    break;
287 		if (c == '\n' || c == DEOF)
288 		    stderror(ERR_UNMATCHED, c1);
289 		if ((c & (QUOTE | TRIM)) == ('\n' | QUOTE)) {
290 		    if ((wp[-1] & TRIM) == '\\')
291 			--wp;
292 		    ++i;
293 		}
294 		if (--i <= 0)
295 		    stderror(ERR_WTOOLONG);
296 		switch (c1) {
297 
298 		case '"':
299 		    /*
300 		     * Leave any `s alone for later. Other chars are all
301 		     * quoted, thus `...` can tell it was within "...".
302 		     */
303 		    *wp++ = c == '`' ? '`' : c | QUOTE;
304 		    break;
305 
306 		case '\'':
307 		    /* Prevent all further interpretation */
308 		    *wp++ = c | QUOTE;
309 		    break;
310 
311 		case '`':
312 		    /* Leave all text alone for later */
313 		    *wp++ = (Char) c;
314 		    break;
315 
316 		default:
317 		    break;
318 		}
319 	    }
320 	    if (c1 == '`')
321 		*wp++ = '`' /* i--; eliminated */;
322 	    sofar = 1;
323 	    if ((wp = Dpack(wbuf, wp)) == NULL)
324 		return (1);
325 	    else {
326 #ifdef masscomp
327     /*
328      * Avoid a nasty message from the RTU 4.1A & RTU 5.0 compiler concerning
329      * the "overuse of registers". According to the compiler release notes,
330      * incorrect code may be produced unless the offending expression is
331      * rewritten. Therefore, we can't just ignore it, DAS DEC-90.
332      */
333 		i = MAXWLEN;
334 		i -= (int) (wp - wbuf);
335 #else /* !masscomp */
336 		i = MAXWLEN - (int) (wp - wbuf);
337 #endif /* masscomp */
338 		done = 0;
339 	    }
340 	    break;
341 
342 	case '\\':
343 	    c = DgetC(0);	/* No $ subst! */
344 	    if (c == '\n' || c == DEOF) {
345 		done = 0;
346 		break;
347 	    }
348 	    c |= QUOTE;
349 	    break;
350 
351 	default:
352 	    break;
353 	}
354 	if (done) {
355 	    unDgetC(c);
356 	    sofar = 1;
357 	    if ((wp = Dpack(wbuf, wp)) == NULL)
358 		return (1);
359 	    else {
360 #ifdef masscomp
361     /*
362      * Avoid a nasty message from the RTU 4.1A & RTU 5.0 compiler concerning
363      * the "overuse of registers". According to the compiler release notes,
364      * incorrect code may be produced unless the offending expression is
365      * rewritten. Therefore, we can't just ignore it, DAS DEC-90.
366      */
367 		i = MAXWLEN;
368 		i -= (int) (wp - wbuf);
369 #else /* !masscomp */
370 		i = MAXWLEN - (int) (wp - wbuf);
371 #endif /* masscomp */
372 		done = 0;
373 	    }
374 	}
375     }
376     /* Really NOTREACHED */
377     return (0);
378 }
379 
380 
381 /*
382  * Get a character, performing $ substitution unless flag is 0.
383  * Any QUOTES character which is returned from a $ expansion is
384  * QUOTEd so that it will not be recognized above.
385  */
386 static int
387 DgetC(flag)
388     register int flag;
389 {
390     register int c;
391 
392 top:
393     if ((c = Dpeekc) != 0) {
394 	Dpeekc = 0;
395 	return (c);
396     }
397     if (lap) {
398 	c = *lap++ & (QUOTE | TRIM);
399 	if (c == 0) {
400 	    lap = 0;
401 	    goto top;
402 	}
403 quotspec:
404 	if (cmap(c, QUOTES))
405 	    return (c | QUOTE);
406 	return (c);
407     }
408     if (dolp) {
409 	if ((c = *dolp++ & (QUOTE | TRIM)) != 0)
410 	    goto quotspec;
411 	if (dolcnt > 0) {
412 	    setDolp(*dolnxt++);
413 	    --dolcnt;
414 	    return (' ');
415 	}
416 	dolp = 0;
417     }
418     if (dolcnt > 0) {
419 	setDolp(*dolnxt++);
420 	--dolcnt;
421 	goto top;
422     }
423     c = Dredc();
424     if (c == '$' && flag) {
425 	Dgetdol();
426 	goto top;
427     }
428     return (c);
429 }
430 
431 static Char *nulvec[] = { NULL };
432 static struct varent nulargv = {nulvec, STRargv, VAR_READWRITE,
433 				{ NULL, NULL, NULL }, 0 };
434 
435 static void
436 dolerror(s)
437     Char   *s;
438 {
439     setname(short2str(s));
440     stderror(ERR_NAME | ERR_RANGE);
441 }
442 
443 /*
444  * Handle the multitudinous $ expansion forms.
445  * Ugh.
446  */
447 static void
448 Dgetdol()
449 {
450     register Char *np;
451     register struct varent *vp = NULL;
452     Char    name[4 * MAXVARLEN + 1];
453     int     c, sc;
454     int     subscr = 0, lwb = 1, upb = 0;
455     bool    dimen = 0, bitset = 0, length = 0;
456     char    tnp;
457     Char    wbuf[BUFSIZE];
458     static Char *dolbang = NULL;
459 
460 #ifdef COMPAT
461     dolmod = dolmcnt = dolwcnt = 0;
462 #else
463     dolnmod = dolmcnt = dolwcnt = 0;
464 #endif /* COMPAT */
465     c = sc = DgetC(0);
466     if (c == '{')
467 	c = DgetC(0);		/* sc is { to take } later */
468     if ((c & TRIM) == '#')
469 	dimen++, c = DgetC(0);	/* $# takes dimension */
470     else if (c == '?')
471 	bitset++, c = DgetC(0);	/* $? tests existence */
472     else if (c == '%')
473 	length++, c = DgetC(0); /* $% returns length in chars */
474     switch (c) {
475 
476     case '!':
477 	if (dimen || bitset || length)
478 	    stderror(ERR_SYNTAX);
479 	if (backpid != 0) {
480 	    if (dolbang)
481 		xfree((ptr_t) dolbang);
482 	    setDolp(dolbang = putn(backpid));
483 	}
484 	goto eatbrac;
485 
486     case '$':
487 	if (dimen || bitset || length)
488 	    stderror(ERR_SYNTAX);
489 	setDolp(doldol);
490 	goto eatbrac;
491 
492 #ifdef COHERENT
493     /* Coherent compiler doesn't allow case-labels that are not
494        constant-expressions */
495 #ifdef SHORT_STRINGS
496     case 0100074:
497 #else /* !SHORT_STRINGS */
498     case 0274:
499 #endif
500 #else /* !COHERENT */
501     case '<'|QUOTE:
502 #endif
503 	if (bitset)
504 	    stderror(ERR_NOTALLOWED, "$?<");
505 	if (dimen)
506 	    stderror(ERR_NOTALLOWED, "$#<");
507 	if (length)
508 	    stderror(ERR_NOTALLOWED, "$%<");
509 	{
510 #ifdef BSDSIGS
511 	    sigmask_t omask = sigsetmask(sigblock(0) & ~sigmask(SIGINT));
512 #else /* !BSDSIGS */
513 	    (void) sigrelse(SIGINT);
514 #endif /* BSDSIGS */
515 	    for (np = wbuf; force_read(OLDSTD, &tnp, 1) == 1; np++) {
516 		*np = (unsigned char) tnp;
517 		if (np >= &wbuf[BUFSIZE - 1])
518 		    stderror(ERR_LTOOLONG);
519 		if (tnp == '\n')
520 		    break;
521 	    }
522 	    *np = 0;
523 #ifdef BSDSIGS
524 	    (void) sigsetmask(omask);
525 #else /* !BSDSIGS */
526 	    (void) sighold(SIGINT);
527 #endif /* BSDSIGS */
528 	}
529 
530 #ifdef COMPAT
531 	/*
532 	 * KLUDGE: dolmod is set here because it will cause setDolp to call
533 	 * domod and thus to copy wbuf. Otherwise setDolp would use it
534 	 * directly. If we saved it ourselves, no one would know when to free
535 	 * it. The actual function of the 'q' causes filename expansion not to
536 	 * be done on the interpolated value.
537 	 */
538 	/*
539 	 * If we do that, then other modifiers don't work.
540 	 * in addition, let the user specify :q if wanted
541 	 * [christos]
542 	 */
543 /*old*/	dolmod = 'q';
544 /*new*/	dolmod[dolnmod++] = 'q';
545 	dolmcnt = 10000;
546 #endif /* COMPAT */
547 
548 	fixDolMod();
549 	setDolp(wbuf);
550 	goto eatbrac;
551 
552     case '*':
553 	(void) Strcpy(name, STRargv);
554 	vp = adrof(STRargv);
555 	subscr = -1;		/* Prevent eating [...] */
556 	break;
557 
558     case DEOF:
559     case '\n':
560 	np = dimen ? STRargv : (bitset ? STRstatus : NULL);
561 	if (np) {
562 	    bitset = 0;
563 	    (void) Strcpy(name, np);
564 	    vp = adrof(np);
565 	    subscr = -1;		/* Prevent eating [...] */
566 	    unDredc(c);
567 	    break;
568 	}
569 	else
570 	    stderror(ERR_SYNTAX);
571 	/*NOTREACHED*/
572 
573     default:
574 	np = name;
575 	if (Isdigit(c)) {
576 	    if (dimen)
577 		stderror(ERR_NOTALLOWED, "$#<num>");
578 	    subscr = 0;
579 	    do {
580 		subscr = subscr * 10 + c - '0';
581 		c = DgetC(0);
582 	    } while (Isdigit(c));
583 	    unDredc(c);
584 	    if (subscr < 0)
585 		stderror(ERR_RANGE);
586 	    if (subscr == 0) {
587 		if (bitset) {
588 		    dolp = dolzero ? STR1 : STR0;
589 		    goto eatbrac;
590 		}
591 		if (ffile == 0)
592 		    stderror(ERR_DOLZERO);
593 		if (length) {
594 		    Char *cp;
595 		    length = Strlen(ffile);
596 		    cp = putn(length);
597 		    addla(cp);
598 		    xfree((ptr_t) cp);
599 		}
600 		else {
601 		    fixDolMod();
602 		    setDolp(ffile);
603 		}
604 		goto eatbrac;
605 	    }
606 #if 0
607 	    if (bitset)
608 		stderror(ERR_NOTALLOWED, "$?<num>");
609 	    if (length)
610 		stderror(ERR_NOTALLOWED, "$%<num>");
611 #endif
612 	    vp = adrof(STRargv);
613 	    if (vp == 0) {
614 		vp = &nulargv;
615 		goto eatmod;
616 	    }
617 	    break;
618 	}
619 	if (!alnum(c)) {
620 	    np = dimen ? STRargv : (bitset ? STRstatus : NULL);
621 	    if (np) {
622 		bitset = 0;
623 		(void) Strcpy(name, np);
624 		vp = adrof(np);
625 		subscr = -1;		/* Prevent eating [...] */
626 		unDredc(c);
627 		break;
628 	    }
629 	    else
630 		stderror(ERR_VARALNUM);
631 	}
632 	for (;;) {
633 	    *np++ = (Char) c;
634 	    c = DgetC(0);
635 	    if (!alnum(c))
636 		break;
637 	    if (np >= &name[MAXVARLEN])
638 		stderror(ERR_VARTOOLONG);
639 	}
640 	*np++ = 0;
641 	unDredc(c);
642 	vp = adrof(name);
643     }
644     if (bitset) {
645 	dolp = (vp || getenv(short2str(name))) ? STR1 : STR0;
646 	goto eatbrac;
647     }
648     if (vp == NULL || vp->vec == NULL) {
649 	np = str2short(getenv(short2str(name)));
650 	if (np) {
651 	    fixDolMod();
652 	    setDolp(np);
653 	    goto eatbrac;
654 	}
655 	udvar(name);
656 	/* NOTREACHED */
657     }
658     c = DgetC(0);
659     upb = blklen(vp->vec);
660     if (dimen == 0 && subscr == 0 && c == '[') {
661 	np = name;
662 	for (;;) {
663 	    c = DgetC(DODOL);	/* Allow $ expand within [ ] */
664 	    if (c == ']')
665 		break;
666 	    if (c == '\n' || c == DEOF)
667 		stderror(ERR_INCBR);
668 	    if (np >= &name[sizeof(name) / sizeof(Char) - 2])
669 		stderror(ERR_VARTOOLONG);
670 	    *np++ = (Char) c;
671 	}
672 	*np = 0, np = name;
673 	if (dolp || dolcnt)	/* $ exp must end before ] */
674 	    stderror(ERR_EXPORD);
675 	if (!*np)
676 	    stderror(ERR_SYNTAX);
677 	if (Isdigit(*np)) {
678 	    int     i;
679 
680 	    for (i = 0; Isdigit(*np); i = i * 10 + *np++ - '0')
681 		continue;
682 	    if ((i < 0 || i > upb) && !any("-*", *np)) {
683 		dolerror(vp->v_name);
684 		return;
685 	    }
686 	    lwb = i;
687 	    if (!*np)
688 		upb = lwb, np = STRstar;
689 	}
690 	if (*np == '*')
691 	    np++;
692 	else if (*np != '-')
693 	    stderror(ERR_MISSING, '-');
694 	else {
695 	    register int i = upb;
696 
697 	    np++;
698 	    if (Isdigit(*np)) {
699 		i = 0;
700 		while (Isdigit(*np))
701 		    i = i * 10 + *np++ - '0';
702 		if (i < 0 || i > upb) {
703 		    dolerror(vp->v_name);
704 		    return;
705 		}
706 	    }
707 	    if (i < lwb)
708 		upb = lwb - 1;
709 	    else
710 		upb = i;
711 	}
712 	if (lwb == 0) {
713 	    if (upb != 0) {
714 		dolerror(vp->v_name);
715 		return;
716 	    }
717 	    upb = -1;
718 	}
719 	if (*np)
720 	    stderror(ERR_SYNTAX);
721     }
722     else {
723 	if (subscr > 0) {
724 	    if (subscr > upb)
725 		lwb = 1, upb = 0;
726 	    else
727 		lwb = upb = subscr;
728 	}
729 	unDredc(c);
730     }
731     if (dimen) {
732 	Char   *cp = putn(upb - lwb + 1);
733 
734 	/* this is a kludge. It prevents Dgetdol() from */
735 	/* pushing erroneous ${#<error> values into the labuf. */
736 	if (sc == '{') {
737 	    c = Dredc();
738 	    if (c != '}')
739 	    {
740 		xfree((ptr_t) cp);
741 		stderror(ERR_MISSING, '}');
742 	        return;
743 	    }
744 	    unDredc(c);
745 	}
746 	addla(cp);
747 	xfree((ptr_t) cp);
748     }
749     else if (length) {
750 	int i;
751 	Char   *cp;
752 	for (i = lwb - 1, length = 0; i < upb; i++)
753 	    length += Strlen(vp->vec[i]);
754 #ifdef notdef
755 	/* We don't want that, since we can always compute it by adding $#xxx */
756 	length += i - 1;	/* Add the number of spaces in */
757 #endif
758 	cp = putn(length);
759 	addla(cp);
760 	xfree((ptr_t) cp);
761     }
762     else {
763 eatmod:
764 	fixDolMod();
765 	dolnxt = &vp->vec[lwb - 1];
766 	dolcnt = upb - lwb + 1;
767     }
768 eatbrac:
769     if (sc == '{') {
770 	c = Dredc();
771 	if (c != '}')
772 	    stderror(ERR_MISSING, '}');
773     }
774 }
775 
776 static void
777 fixDolMod()
778 {
779     register int c;
780 
781     c = DgetC(0);
782     if (c == ':') {
783 #ifndef COMPAT
784 	do {
785 #endif /* COMPAT */
786 	    c = DgetC(0), dolmcnt = 1, dolwcnt = 1;
787 	    if (c == 'g' || c == 'a') {
788 		if (c == 'g')
789 		    dolmcnt = 10000;
790 		else
791 		    dolwcnt = 10000;
792 		c = DgetC(0);
793 	    }
794 	    if ((c == 'g' && dolmcnt != 10000) ||
795 		(c == 'a' && dolwcnt != 10000)) {
796 		if (c == 'g')
797 		    dolmcnt = 10000;
798 		else
799 		    dolwcnt = 10000;
800 		c = DgetC(0);
801 	    }
802 
803 	    if (c == 's') {	/* [eichin:19910926.0755EST] */
804 		int delimcnt = 2;
805 		int delim = DgetC(0);
806 		dolmod[dolnmod++] = (Char) c;
807 		dolmod[dolnmod++] = (Char) delim;
808 
809 		if (!delim || letter(delim)
810 		    || Isdigit(delim) || any(" \t\n", delim)) {
811 		    seterror(ERR_BADSUBST);
812 		    break;
813 		}
814 		while ((c = DgetC(0)) != (-1)) {
815 		    dolmod[dolnmod++] = (Char) c;
816 		    if(c == delim) delimcnt--;
817 		    if(!delimcnt) break;
818 		}
819 		if(delimcnt) {
820 		    seterror(ERR_BADSUBST);
821 		    break;
822 		}
823 		continue;
824 	    }
825 	    if (!any("luhtrqxes", c))
826 		stderror(ERR_BADMOD, c);
827 #ifndef COMPAT
828 	    dolmod[dolnmod++] = (Char) c;
829 #else
830 	    dolmod = (Char) c;
831 #endif /* COMPAT */
832 	    if (c == 'q')
833 		dolmcnt = 10000;
834 #ifndef COMPAT
835 	}
836 	while ((c = DgetC(0)) == ':');
837 	unDredc(c);
838 #endif /* COMPAT */
839     }
840     else
841 	unDredc(c);
842 }
843 
844 static void
845 setDolp(cp)
846     register Char *cp;
847 {
848     register Char *dp;
849 #ifndef COMPAT
850     int i;
851 #endif /* COMPAT */
852 
853 #ifdef COMPAT
854     if (dolmod == 0 || dolmcnt == 0) {
855 #else
856     if (dolnmod == 0 || dolmcnt == 0) {
857 #endif /* COMPAT */
858 	dolp = cp;
859 	return;
860     }
861 #ifdef COMPAT
862     dp = domod(cp, dolmod);
863 #else
864     dp = cp = Strsave(cp);
865     for (i = 0; i < dolnmod; i++) {
866 	/* handle s// [eichin:19910926.0510EST] */
867 	if(dolmod[i] == 's') {
868 	    int delim;
869 	    Char *lhsub, *rhsub, *np;
870 	    size_t lhlen = 0, rhlen = 0;
871 	    int didmod = 0;
872 
873 	    delim = dolmod[++i];
874 	    if (!delim || letter(delim)
875 		|| Isdigit(delim) || any(" \t\n", delim)) {
876 		seterror(ERR_BADSUBST);
877 		break;
878 	    }
879 	    lhsub = &dolmod[++i];
880 	    while(dolmod[i] != delim && dolmod[++i]) {
881 		lhlen++;
882 	    }
883 	    dolmod[i] = 0;
884 	    rhsub = &dolmod[++i];
885 	    while(dolmod[i] != delim && dolmod[++i]) {
886 		rhlen++;
887 	    }
888 	    dolmod[i] = 0;
889 
890 	    do {
891 		strip(lhsub);
892 		strip(cp);
893 		dp = Strstr(cp, lhsub);
894 		if (dp) {
895 		    np = (Char *) xmalloc((size_t)
896 					  ((Strlen(cp) + 1 - lhlen + rhlen) *
897 					  sizeof(Char)));
898 		    (void) Strncpy(np, cp, (size_t) (dp - cp));
899 		    (void) Strcpy(np + (dp - cp), rhsub);
900 		    (void) Strcpy(np + (dp - cp) + rhlen, dp + lhlen);
901 
902 		    xfree((ptr_t) cp);
903 		    dp = cp = np;
904 		    didmod = 1;
905 		} else {
906 		    /* should this do a seterror? */
907 		    break;
908 		}
909 	    }
910 	    while (dolwcnt == 10000);
911 	    /*
912 	     * restore dolmod for additional words
913 	     */
914 	    dolmod[i] = rhsub[-1] = (Char) delim;
915 	    if (didmod)
916 		dolmcnt--;
917 #ifdef notdef
918 	    else
919 		break;
920 #endif
921         } else {
922 	    int didmod = 0;
923 
924 	    do {
925 		if ((dp = domod(cp, dolmod[i])) != NULL) {
926 		    didmod = 1;
927 		    if (Strcmp(cp, dp) == 0) {
928 			xfree((ptr_t) cp);
929 			cp = dp;
930 			break;
931 		    }
932 		    else {
933 			xfree((ptr_t) cp);
934 			cp = dp;
935 		    }
936 		}
937 		else
938 		    break;
939 	    }
940 	    while (dolwcnt == 10000);
941 	    dp = cp;
942 	    if (didmod)
943 		dolmcnt--;
944 #ifdef notdef
945 	    else
946 		break;
947 #endif
948 	}
949     }
950 #endif /* COMPAT */
951 
952     if (dp) {
953 #ifdef COMPAT
954 	dolmcnt--;
955 #endif /* COMPAT */
956 	addla(dp);
957 	xfree((ptr_t) dp);
958     }
959 #ifndef COMPAT
960     else
961 	addla(cp);
962 #endif /* COMPAT */
963 
964     dolp = STRNULL;
965     if (seterr)
966 	stderror(ERR_OLD);
967 }
968 
969 static void
970 unDredc(c)
971     int     c;
972 {
973 
974     Dpeekrd = c;
975 }
976 
977 static int
978 Dredc()
979 {
980     register int c;
981 
982     if ((c = Dpeekrd) != 0) {
983 	Dpeekrd = 0;
984 	return (c);
985     }
986     if (Dcp && (c = *Dcp++))
987 	return (c & (QUOTE | TRIM));
988     if (*Dvp == 0) {
989 	Dcp = 0;
990 	return (DEOF);
991     }
992     Dcp = *Dvp++;
993     return (' ');
994 }
995 
996 static void
997 Dtestq(c)
998     register int c;
999 {
1000 
1001     if (cmap(c, QUOTES))
1002 	gflag = 1;
1003 }
1004 
1005 /*
1006  * Form a shell temporary file (in unit 0) from the words
1007  * of the shell input up to EOF or a line the same as "term".
1008  * Unit 0 should have been closed before this call.
1009  */
1010 void
1011 heredoc(term)
1012     Char   *term;
1013 {
1014     int c;
1015     Char   *Dv[2];
1016     Char    obuf[BUFSIZE], lbuf[BUFSIZE], mbuf[BUFSIZE];
1017     int     ocnt, lcnt, mcnt;
1018     register Char *lbp, *obp, *mbp;
1019     Char  **vp;
1020     bool    quoted;
1021     char   *tmp;
1022 #ifndef WINNT_NATIVE
1023     struct timeval tv;
1024 
1025 again:
1026 #endif /* WINNT_NATIVE */
1027     tmp = short2str(shtemp);
1028 #ifndef O_CREAT
1029 # define O_CREAT 0
1030     if (creat(tmp, 0600) < 0)
1031 	stderror(ERR_SYSTEM, tmp, strerror(errno));
1032 #endif
1033     (void) close(0);
1034 #ifndef O_TEMPORARY
1035 # define O_TEMPORARY 0
1036 #endif
1037 #ifndef O_EXCL
1038 # define O_EXCL 0
1039 #endif
1040     if (open(tmp, O_RDWR|O_CREAT|O_EXCL|O_TEMPORARY|O_LARGEFILE, 0600) == -1) {
1041 	int oerrno = errno;
1042 #ifndef WINNT_NATIVE
1043 	if (errno == EEXIST) {
1044 	    if (unlink(tmp) == -1) {
1045 		(void) gettimeofday(&tv, NULL);
1046 		shtemp = Strspl(STRtmpsh, putn((((int)tv.tv_sec) ^
1047 		    ((int)tv.tv_usec) ^ ((int)getpid())) & 0x00ffffff));
1048 	    }
1049 	    goto again;
1050 	}
1051 #endif /* WINNT_NATIVE */
1052 	(void) unlink(tmp);
1053 	errno = oerrno;
1054  	stderror(ERR_SYSTEM, tmp, strerror(errno));
1055     }
1056     (void) unlink(tmp);		/* 0 0 inode! */
1057     Dv[0] = term;
1058     Dv[1] = NULL;
1059     gflag = 0;
1060     trim(Dv);
1061     rscan(Dv, Dtestq);
1062     quoted = gflag;
1063     ocnt = BUFSIZE;
1064     obp = obuf;
1065     inheredoc = 1;
1066 #ifdef WINNT_NATIVE
1067     __dup_stdin = 1;
1068 #endif /* WINNT_NATIVE */
1069 #ifdef O_TEXT
1070     setmode(1, O_TEXT);
1071 #endif
1072 #ifdef O_BINARY
1073     setmode(0, O_BINARY);
1074 #endif
1075     for (;;) {
1076 	/*
1077 	 * Read up a line
1078 	 */
1079 	lbp = lbuf;
1080 	lcnt = BUFSIZE - 4;
1081 	for (;;) {
1082 	    c = readc(1);	/* 1 -> Want EOF returns */
1083 	    if (c < 0 || c == '\n')
1084 		break;
1085 	    if ((c &= TRIM) != 0) {
1086 		*lbp++ = (Char) c;
1087 		if (--lcnt < 0) {
1088 		    setname("<<");
1089 		    stderror(ERR_NAME | ERR_OVERFLOW);
1090 		}
1091 	    }
1092 	}
1093 	*lbp = 0;
1094 
1095 	/*
1096 	 * Check for EOF or compare to terminator -- before expansion
1097 	 */
1098 	if (c < 0 || eq(lbuf, term)) {
1099 	    (void) write(0, short2str(obuf), (size_t) (BUFSIZE - ocnt));
1100 	    (void) lseek(0, (off_t) 0, L_SET);
1101 	    inheredoc = 0;
1102 	    return;
1103 	}
1104 
1105 	/*
1106 	 * If term was quoted or -n just pass it on
1107 	 */
1108 	if (quoted || noexec) {
1109 	    *lbp++ = '\n';
1110 	    *lbp = 0;
1111 	    for (lbp = lbuf; (c = *lbp++) != 0;) {
1112 		*obp++ = (Char) c;
1113 		if (--ocnt == 0) {
1114 		    (void) write(0, short2str(obuf), BUFSIZE);
1115 		    obp = obuf;
1116 		    ocnt = BUFSIZE;
1117 		}
1118 	    }
1119 	    continue;
1120 	}
1121 
1122 	/*
1123 	 * Term wasn't quoted so variable and then command expand the input
1124 	 * line
1125 	 */
1126 	Dcp = lbuf;
1127 	Dvp = Dv + 1;
1128 	mbp = mbuf;
1129 	mcnt = BUFSIZE - 4;
1130 	for (;;) {
1131 	    c = DgetC(DODOL);
1132 	    if (c == DEOF)
1133 		break;
1134 	    if ((c &= TRIM) == 0)
1135 		continue;
1136 	    /* \ quotes \ $ ` here */
1137 	    if (c == '\\') {
1138 		c = DgetC(0);
1139 		if (!any("$\\`", c))
1140 		    unDgetC(c | QUOTE), c = '\\';
1141 		else
1142 		    c |= QUOTE;
1143 	    }
1144 	    *mbp++ = (Char) c;
1145 	    if (--mcnt == 0) {
1146 		setname("<<");
1147 		stderror(ERR_NAME | ERR_OVERFLOW);
1148 	    }
1149 	}
1150 	*mbp++ = 0;
1151 
1152 	/*
1153 	 * If any ` in line do command substitution
1154 	 */
1155 	mbp = mbuf;
1156 	if (Strchr(mbp, '`') != NULL) {
1157 	    /*
1158 	     * 1 arg to dobackp causes substitution to be literal. Words are
1159 	     * broken only at newlines so that all blanks and tabs are
1160 	     * preserved.  Blank lines (null words) are not discarded.
1161 	     */
1162 	    vp = dobackp(mbuf, 1);
1163 	}
1164 	else
1165 	    /* Setup trivial vector similar to return of dobackp */
1166 	    Dv[0] = mbp, Dv[1] = NULL, vp = Dv;
1167 
1168 	/*
1169 	 * Resurrect the words from the command substitution each separated by
1170 	 * a newline.  Note that the last newline of a command substitution
1171 	 * will have been discarded, but we put a newline after the last word
1172 	 * because this represents the newline after the last input line!
1173 	 */
1174 	for (; *vp; vp++) {
1175 	    for (mbp = *vp; *mbp; mbp++) {
1176 		*obp++ = *mbp & TRIM;
1177 		if (--ocnt == 0) {
1178 		    (void) write(0, short2str(obuf), BUFSIZE);
1179 		    obp = obuf;
1180 		    ocnt = BUFSIZE;
1181 		}
1182 	    }
1183 	    *obp++ = '\n';
1184 	    if (--ocnt == 0) {
1185 		(void) write(0, short2str(obuf), BUFSIZE);
1186 		obp = obuf;
1187 		ocnt = BUFSIZE;
1188 	    }
1189 	}
1190 	if (pargv)
1191 	    blkfree(pargv), pargv = 0;
1192     }
1193 }
1194