Add the DragonFly cvs id and perform general cleanups on cvs/rcs/sccs ids. Most
[dragonfly.git] / bin / sh / expand.c
CommitLineData
984263bc
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1/*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
1de703da
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35 *
36 * @(#)expand.c 8.5 (Berkeley) 5/15/95
37 * $FreeBSD: src/bin/sh/expand.c,v 1.31.2.5 2003/01/17 07:44:01 tjr Exp $
38 * $DragonFly: src/bin/sh/expand.c,v 1.2 2003/06/17 04:22:50 dillon Exp $
984263bc
MD
39 */
40
984263bc
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41#include <sys/types.h>
42#include <sys/time.h>
43#include <sys/stat.h>
44#include <errno.h>
45#include <dirent.h>
46#include <unistd.h>
47#include <pwd.h>
48#include <stdlib.h>
49#include <limits.h>
50#include <stdio.h>
51
52/*
53 * Routines to expand arguments to commands. We have to deal with
54 * backquotes, shell variables, and file metacharacters.
55 */
56
57#include "shell.h"
58#include "main.h"
59#include "nodes.h"
60#include "eval.h"
61#include "expand.h"
62#include "syntax.h"
63#include "parser.h"
64#include "jobs.h"
65#include "options.h"
66#include "var.h"
67#include "input.h"
68#include "output.h"
69#include "memalloc.h"
70#include "error.h"
71#include "mystring.h"
72#include "arith.h"
73#include "show.h"
74
75/*
76 * Structure specifying which parts of the string should be searched
77 * for IFS characters.
78 */
79
80struct ifsregion {
81 struct ifsregion *next; /* next region in list */
82 int begoff; /* offset of start of region */
83 int endoff; /* offset of end of region */
84 int nulonly; /* search for nul bytes only */
85};
86
87
88char *expdest; /* output of current string */
89struct nodelist *argbackq; /* list of back quote expressions */
90struct ifsregion ifsfirst; /* first struct in list of ifs regions */
91struct ifsregion *ifslastp; /* last struct in list */
92struct arglist exparg; /* holds expanded arg list */
93
94STATIC void argstr(char *, int);
95STATIC char *exptilde(char *, int);
96STATIC void expbackq(union node *, int, int);
97STATIC int subevalvar(char *, char *, int, int, int, int);
98STATIC char *evalvar(char *, int);
99STATIC int varisset(char *, int);
100STATIC void varvalue(char *, int, int);
101STATIC void recordregion(int, int, int);
102STATIC void removerecordregions(int);
103STATIC void ifsbreakup(char *, struct arglist *);
104STATIC void expandmeta(struct strlist *, int);
105STATIC void expmeta(char *, char *);
106STATIC void addfname(char *);
107STATIC struct strlist *expsort(struct strlist *);
108STATIC struct strlist *msort(struct strlist *, int);
109STATIC int pmatch(char *, char *, int);
110STATIC char *cvtnum(int, char *);
111STATIC int collate_range_cmp(int, int);
112
113STATIC int
114collate_range_cmp (int c1, int c2)
115{
116 static char s1[2], s2[2];
117 int ret;
118
119 c1 &= UCHAR_MAX;
120 c2 &= UCHAR_MAX;
121 if (c1 == c2)
122 return (0);
123 s1[0] = c1;
124 s2[0] = c2;
125 if ((ret = strcoll(s1, s2)) != 0)
126 return (ret);
127 return (c1 - c2);
128}
129
130/*
131 * Expand shell variables and backquotes inside a here document.
132 * union node *arg the document
133 * int fd; where to write the expanded version
134 */
135
136void
137expandhere(union node *arg, int fd)
138{
139 herefd = fd;
140 expandarg(arg, (struct arglist *)NULL, 0);
141 xwrite(fd, stackblock(), expdest - stackblock());
142}
143
144
145/*
146 * Perform variable substitution and command substitution on an argument,
147 * placing the resulting list of arguments in arglist. If EXP_FULL is true,
148 * perform splitting and file name expansion. When arglist is NULL, perform
149 * here document expansion.
150 */
151
152void
153expandarg(union node *arg, struct arglist *arglist, int flag)
154{
155 struct strlist *sp;
156 char *p;
157
158 argbackq = arg->narg.backquote;
159 STARTSTACKSTR(expdest);
160 ifsfirst.next = NULL;
161 ifslastp = NULL;
162 argstr(arg->narg.text, flag);
163 if (arglist == NULL) {
164 return; /* here document expanded */
165 }
166 STPUTC('\0', expdest);
167 p = grabstackstr(expdest);
168 exparg.lastp = &exparg.list;
169 /*
170 * TODO - EXP_REDIR
171 */
172 if (flag & EXP_FULL) {
173 ifsbreakup(p, &exparg);
174 *exparg.lastp = NULL;
175 exparg.lastp = &exparg.list;
176 expandmeta(exparg.list, flag);
177 } else {
178 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
179 rmescapes(p);
180 sp = (struct strlist *)stalloc(sizeof (struct strlist));
181 sp->text = p;
182 *exparg.lastp = sp;
183 exparg.lastp = &sp->next;
184 }
185 while (ifsfirst.next != NULL) {
186 struct ifsregion *ifsp;
187 INTOFF;
188 ifsp = ifsfirst.next->next;
189 ckfree(ifsfirst.next);
190 ifsfirst.next = ifsp;
191 INTON;
192 }
193 *exparg.lastp = NULL;
194 if (exparg.list) {
195 *arglist->lastp = exparg.list;
196 arglist->lastp = exparg.lastp;
197 }
198}
199
200
201
202/*
203 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC
204 * characters to allow for further processing. Otherwise treat
205 * $@ like $* since no splitting will be performed.
206 */
207
208STATIC void
209argstr(char *p, int flag)
210{
211 char c;
212 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */
213 int firsteq = 1;
214
215 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
216 p = exptilde(p, flag);
217 for (;;) {
218 switch (c = *p++) {
219 case '\0':
220 case CTLENDVAR: /* ??? */
221 goto breakloop;
222 case CTLQUOTEMARK:
223 /* "$@" syntax adherence hack */
224 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=')
225 break;
226 if ((flag & EXP_FULL) != 0)
227 STPUTC(c, expdest);
228 break;
229 case CTLESC:
230 if (quotes)
231 STPUTC(c, expdest);
232 c = *p++;
233 STPUTC(c, expdest);
234 break;
235 case CTLVAR:
236 p = evalvar(p, flag);
237 break;
238 case CTLBACKQ:
239 case CTLBACKQ|CTLQUOTE:
240 expbackq(argbackq->n, c & CTLQUOTE, flag);
241 argbackq = argbackq->next;
242 break;
243 case CTLENDARI:
244 expari(flag);
245 break;
246 case ':':
247 case '=':
248 /*
249 * sort of a hack - expand tildes in variable
250 * assignments (after the first '=' and after ':'s).
251 */
252 STPUTC(c, expdest);
253 if (flag & EXP_VARTILDE && *p == '~') {
254 if (c == '=') {
255 if (firsteq)
256 firsteq = 0;
257 else
258 break;
259 }
260 p = exptilde(p, flag);
261 }
262 break;
263 default:
264 STPUTC(c, expdest);
265 }
266 }
267breakloop:;
268}
269
270STATIC char *
271exptilde(char *p, int flag)
272{
273 char c, *startp = p;
274 struct passwd *pw;
275 char *home;
276 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
277
278 while ((c = *p) != '\0') {
279 switch(c) {
280 case CTLESC:
281 return (startp);
282 case CTLQUOTEMARK:
283 return (startp);
284 case ':':
285 if (flag & EXP_VARTILDE)
286 goto done;
287 break;
288 case '/':
289 goto done;
290 }
291 p++;
292 }
293done:
294 *p = '\0';
295 if (*(startp+1) == '\0') {
296 if ((home = lookupvar("HOME")) == NULL)
297 goto lose;
298 } else {
299 if ((pw = getpwnam(startp+1)) == NULL)
300 goto lose;
301 home = pw->pw_dir;
302 }
303 if (*home == '\0')
304 goto lose;
305 *p = c;
306 while ((c = *home++) != '\0') {
307 if (quotes && SQSYNTAX[(int)c] == CCTL)
308 STPUTC(CTLESC, expdest);
309 STPUTC(c, expdest);
310 }
311 return (p);
312lose:
313 *p = c;
314 return (startp);
315}
316
317
318STATIC void
319removerecordregions(int endoff)
320{
321 if (ifslastp == NULL)
322 return;
323
324 if (ifsfirst.endoff > endoff) {
325 while (ifsfirst.next != NULL) {
326 struct ifsregion *ifsp;
327 INTOFF;
328 ifsp = ifsfirst.next->next;
329 ckfree(ifsfirst.next);
330 ifsfirst.next = ifsp;
331 INTON;
332 }
333 if (ifsfirst.begoff > endoff)
334 ifslastp = NULL;
335 else {
336 ifslastp = &ifsfirst;
337 ifsfirst.endoff = endoff;
338 }
339 return;
340 }
341
342 ifslastp = &ifsfirst;
343 while (ifslastp->next && ifslastp->next->begoff < endoff)
344 ifslastp=ifslastp->next;
345 while (ifslastp->next != NULL) {
346 struct ifsregion *ifsp;
347 INTOFF;
348 ifsp = ifslastp->next->next;
349 ckfree(ifslastp->next);
350 ifslastp->next = ifsp;
351 INTON;
352 }
353 if (ifslastp->endoff > endoff)
354 ifslastp->endoff = endoff;
355}
356
357/*
358 * Expand arithmetic expression. Backup to start of expression,
359 * evaluate, place result in (backed up) result, adjust string position.
360 */
361void
362expari(int flag)
363{
364 char *p, *start;
365 int result;
366 int begoff;
367 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
368 int quoted;
369
370
371 /*
372 * This routine is slightly over-complicated for
373 * efficiency. First we make sure there is
374 * enough space for the result, which may be bigger
375 * than the expression if we add exponentiation. Next we
376 * scan backwards looking for the start of arithmetic. If the
377 * next previous character is a CTLESC character, then we
378 * have to rescan starting from the beginning since CTLESC
379 * characters have to be processed left to right.
380 */
381#if INT_MAX / 1000000000 >= 10 || INT_MIN / 1000000000 <= -10
382#error "integers with more than 10 digits are not supported"
383#endif
384 CHECKSTRSPACE(12 - 2, expdest);
385 USTPUTC('\0', expdest);
386 start = stackblock();
387 p = expdest - 2;
388 while (p >= start && *p != CTLARI)
389 --p;
390 if (p < start || *p != CTLARI)
391 error("missing CTLARI (shouldn't happen)");
392 if (p > start && *(p - 1) == CTLESC)
393 for (p = start; *p != CTLARI; p++)
394 if (*p == CTLESC)
395 p++;
396
397 if (p[1] == '"')
398 quoted=1;
399 else
400 quoted=0;
401 begoff = p - start;
402 removerecordregions(begoff);
403 if (quotes)
404 rmescapes(p+2);
405 result = arith(p+2);
406 fmtstr(p, 12, "%d", result);
407 while (*p++)
408 ;
409 if (quoted == 0)
410 recordregion(begoff, p - 1 - start, 0);
411 result = expdest - p + 1;
412 STADJUST(-result, expdest);
413}
414
415
416/*
417 * Expand stuff in backwards quotes.
418 */
419
420STATIC void
421expbackq(union node *cmd, int quoted, int flag)
422{
423 struct backcmd in;
424 int i;
425 char buf[128];
426 char *p;
427 char *dest = expdest;
428 struct ifsregion saveifs, *savelastp;
429 struct nodelist *saveargbackq;
430 char lastc;
431 int startloc = dest - stackblock();
432 char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
433 int saveherefd;
434 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
435
436 INTOFF;
437 saveifs = ifsfirst;
438 savelastp = ifslastp;
439 saveargbackq = argbackq;
440 saveherefd = herefd;
441 herefd = -1;
442 p = grabstackstr(dest);
443 evalbackcmd(cmd, &in);
444 ungrabstackstr(p, dest);
445 ifsfirst = saveifs;
446 ifslastp = savelastp;
447 argbackq = saveargbackq;
448 herefd = saveherefd;
449
450 p = in.buf;
451 lastc = '\0';
452 for (;;) {
453 if (--in.nleft < 0) {
454 if (in.fd < 0)
455 break;
456 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR);
457 TRACE(("expbackq: read returns %d\n", i));
458 if (i <= 0)
459 break;
460 p = buf;
461 in.nleft = i - 1;
462 }
463 lastc = *p++;
464 if (lastc != '\0') {
465 if (quotes && syntax[(int)lastc] == CCTL)
466 STPUTC(CTLESC, dest);
467 STPUTC(lastc, dest);
468 }
469 }
470
471 /* Eat all trailing newlines */
472 for (p--; lastc == '\n'; lastc = *--p)
473 STUNPUTC(dest);
474
475 if (in.fd >= 0)
476 close(in.fd);
477 if (in.buf)
478 ckfree(in.buf);
479 if (in.jp)
480 exitstatus = waitforjob(in.jp, (int *)NULL);
481 if (quoted == 0)
482 recordregion(startloc, dest - stackblock(), 0);
483 TRACE(("evalbackq: size=%d: \"%.*s\"\n",
484 (dest - stackblock()) - startloc,
485 (dest - stackblock()) - startloc,
486 stackblock() + startloc));
487 expdest = dest;
488 INTON;
489}
490
491
492
493STATIC int
494subevalvar(char *p, char *str, int strloc, int subtype, int startloc,
495 int varflags)
496{
497 char *startp;
498 char *loc = NULL;
499 char *q;
500 int c = 0;
501 int saveherefd = herefd;
502 struct nodelist *saveargbackq = argbackq;
503 int amount;
504
505 herefd = -1;
506 argstr(p, 0);
507 STACKSTRNUL(expdest);
508 herefd = saveherefd;
509 argbackq = saveargbackq;
510 startp = stackblock() + startloc;
511 if (str == NULL)
512 str = stackblock() + strloc;
513
514 switch (subtype) {
515 case VSASSIGN:
516 setvar(str, startp, 0);
517 amount = startp - expdest;
518 STADJUST(amount, expdest);
519 varflags &= ~VSNUL;
520 if (c != 0)
521 *loc = c;
522 return 1;
523
524 case VSQUESTION:
525 if (*p != CTLENDVAR) {
526 outfmt(&errout, "%s\n", startp);
527 error((char *)NULL);
528 }
529 error("%.*s: parameter %snot set", p - str - 1,
530 str, (varflags & VSNUL) ? "null or "
531 : nullstr);
532 return 0;
533
534 case VSTRIMLEFT:
535 for (loc = startp; loc < str; loc++) {
536 c = *loc;
537 *loc = '\0';
538 if (patmatch(str, startp, varflags & VSQUOTE)) {
539 *loc = c;
540 goto recordleft;
541 }
542 *loc = c;
543 if ((varflags & VSQUOTE) && *loc == CTLESC)
544 loc++;
545 }
546 return 0;
547
548 case VSTRIMLEFTMAX:
549 for (loc = str - 1; loc >= startp;) {
550 c = *loc;
551 *loc = '\0';
552 if (patmatch(str, startp, varflags & VSQUOTE)) {
553 *loc = c;
554 goto recordleft;
555 }
556 *loc = c;
557 loc--;
558 if ((varflags & VSQUOTE) && loc > startp &&
559 *(loc - 1) == CTLESC) {
560 for (q = startp; q < loc; q++)
561 if (*q == CTLESC)
562 q++;
563 if (q > loc)
564 loc--;
565 }
566 }
567 return 0;
568
569 case VSTRIMRIGHT:
570 for (loc = str - 1; loc >= startp;) {
571 if (patmatch(str, loc, varflags & VSQUOTE)) {
572 amount = loc - expdest;
573 STADJUST(amount, expdest);
574 return 1;
575 }
576 loc--;
577 if ((varflags & VSQUOTE) && loc > startp &&
578 *(loc - 1) == CTLESC) {
579 for (q = startp; q < loc; q++)
580 if (*q == CTLESC)
581 q++;
582 if (q > loc)
583 loc--;
584 }
585 }
586 return 0;
587
588 case VSTRIMRIGHTMAX:
589 for (loc = startp; loc < str - 1; loc++) {
590 if (patmatch(str, loc, varflags & VSQUOTE)) {
591 amount = loc - expdest;
592 STADJUST(amount, expdest);
593 return 1;
594 }
595 if ((varflags & VSQUOTE) && *loc == CTLESC)
596 loc++;
597 }
598 return 0;
599
600
601 default:
602 abort();
603 }
604
605recordleft:
606 amount = ((str - 1) - (loc - startp)) - expdest;
607 STADJUST(amount, expdest);
608 while (loc != str - 1)
609 *startp++ = *loc++;
610 return 1;
611}
612
613
614/*
615 * Expand a variable, and return a pointer to the next character in the
616 * input string.
617 */
618
619STATIC char *
620evalvar(char *p, int flag)
621{
622 int subtype;
623 int varflags;
624 char *var;
625 char *val;
626 int patloc;
627 int c;
628 int set;
629 int special;
630 int startloc;
631 int varlen;
632 int easy;
633 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
634
635 varflags = *p++;
636 subtype = varflags & VSTYPE;
637 var = p;
638 special = 0;
639 if (! is_name(*p))
640 special = 1;
641 p = strchr(p, '=') + 1;
642again: /* jump here after setting a variable with ${var=text} */
643 if (special) {
644 set = varisset(var, varflags & VSNUL);
645 val = NULL;
646 } else {
647 val = bltinlookup(var, 1);
648 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
649 val = NULL;
650 set = 0;
651 } else
652 set = 1;
653 }
654 varlen = 0;
655 startloc = expdest - stackblock();
656 if (!set && uflag) {
657 switch (subtype) {
658 case VSNORMAL:
659 case VSTRIMLEFT:
660 case VSTRIMLEFTMAX:
661 case VSTRIMRIGHT:
662 case VSTRIMRIGHTMAX:
663 case VSLENGTH:
664 error("%.*s: parameter not set", p - var - 1, var);
665 }
666 }
667 if (set && subtype != VSPLUS) {
668 /* insert the value of the variable */
669 if (special) {
670 varvalue(var, varflags & VSQUOTE, flag & EXP_FULL);
671 if (subtype == VSLENGTH) {
672 varlen = expdest - stackblock() - startloc;
673 STADJUST(-varlen, expdest);
674 }
675 } else {
676 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX
677 : BASESYNTAX;
678
679 if (subtype == VSLENGTH) {
680 for (;*val; val++)
681 varlen++;
682 }
683 else {
684 while (*val) {
685 if (quotes &&
686 syntax[(int)*val] == CCTL)
687 STPUTC(CTLESC, expdest);
688 STPUTC(*val++, expdest);
689 }
690
691 }
692 }
693 }
694
695 if (subtype == VSPLUS)
696 set = ! set;
697
698 easy = ((varflags & VSQUOTE) == 0 ||
699 (*var == '@' && shellparam.nparam != 1));
700
701
702 switch (subtype) {
703 case VSLENGTH:
704 expdest = cvtnum(varlen, expdest);
705 goto record;
706
707 case VSNORMAL:
708 if (!easy)
709 break;
710record:
711 recordregion(startloc, expdest - stackblock(),
712 varflags & VSQUOTE);
713 break;
714
715 case VSPLUS:
716 case VSMINUS:
717 if (!set) {
718 argstr(p, flag);
719 break;
720 }
721 if (easy)
722 goto record;
723 break;
724
725 case VSTRIMLEFT:
726 case VSTRIMLEFTMAX:
727 case VSTRIMRIGHT:
728 case VSTRIMRIGHTMAX:
729 if (!set)
730 break;
731 /*
732 * Terminate the string and start recording the pattern
733 * right after it
734 */
735 STPUTC('\0', expdest);
736 patloc = expdest - stackblock();
737 if (subevalvar(p, NULL, patloc, subtype,
738 startloc, varflags) == 0) {
739 int amount = (expdest - stackblock() - patloc) + 1;
740 STADJUST(-amount, expdest);
741 }
742 /* Remove any recorded regions beyond start of variable */
743 removerecordregions(startloc);
744 goto record;
745
746 case VSASSIGN:
747 case VSQUESTION:
748 if (!set) {
749 if (subevalvar(p, var, 0, subtype, startloc, varflags)) {
750 varflags &= ~VSNUL;
751 /*
752 * Remove any recorded regions beyond
753 * start of variable
754 */
755 removerecordregions(startloc);
756 goto again;
757 }
758 break;
759 }
760 if (easy)
761 goto record;
762 break;
763
764 default:
765 abort();
766 }
767
768 if (subtype != VSNORMAL) { /* skip to end of alternative */
769 int nesting = 1;
770 for (;;) {
771 if ((c = *p++) == CTLESC)
772 p++;
773 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
774 if (set)
775 argbackq = argbackq->next;
776 } else if (c == CTLVAR) {
777 if ((*p++ & VSTYPE) != VSNORMAL)
778 nesting++;
779 } else if (c == CTLENDVAR) {
780 if (--nesting == 0)
781 break;
782 }
783 }
784 }
785 return p;
786}
787
788
789
790/*
791 * Test whether a specialized variable is set.
792 */
793
794STATIC int
795varisset(char *name, int nulok)
796{
797
798 if (*name == '!')
799 return backgndpid != -1;
800 else if (*name == '@' || *name == '*') {
801 if (*shellparam.p == NULL)
802 return 0;
803
804 if (nulok) {
805 char **av;
806
807 for (av = shellparam.p; *av; av++)
808 if (**av != '\0')
809 return 1;
810 return 0;
811 }
812 } else if (is_digit(*name)) {
813 char *ap;
814 int num = atoi(name);
815
816 if (num > shellparam.nparam)
817 return 0;
818
819 if (num == 0)
820 ap = arg0;
821 else
822 ap = shellparam.p[num - 1];
823
824 if (nulok && (ap == NULL || *ap == '\0'))
825 return 0;
826 }
827 return 1;
828}
829
830
831
832/*
833 * Add the value of a specialized variable to the stack string.
834 */
835
836STATIC void
837varvalue(char *name, int quoted, int allow_split)
838{
839 int num;
840 char *p;
841 int i;
842 extern int oexitstatus;
843 char sep;
844 char **ap;
845 char const *syntax;
846
847#define STRTODEST(p) \
848 do {\
849 if (allow_split) { \
850 syntax = quoted? DQSYNTAX : BASESYNTAX; \
851 while (*p) { \
852 if (syntax[(int)*p] == CCTL) \
853 STPUTC(CTLESC, expdest); \
854 STPUTC(*p++, expdest); \
855 } \
856 } else \
857 while (*p) \
858 STPUTC(*p++, expdest); \
859 } while (0)
860
861
862 switch (*name) {
863 case '$':
864 num = rootpid;
865 goto numvar;
866 case '?':
867 num = oexitstatus;
868 goto numvar;
869 case '#':
870 num = shellparam.nparam;
871 goto numvar;
872 case '!':
873 num = backgndpid;
874numvar:
875 expdest = cvtnum(num, expdest);
876 break;
877 case '-':
878 for (i = 0 ; i < NOPTS ; i++) {
879 if (optlist[i].val)
880 STPUTC(optlist[i].letter, expdest);
881 }
882 break;
883 case '@':
884 if (allow_split && quoted) {
885 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
886 STRTODEST(p);
887 if (*ap)
888 STPUTC('\0', expdest);
889 }
890 break;
891 }
892 /* fall through */
893 case '*':
894 if (ifsset() != 0)
895 sep = ifsval()[0];
896 else
897 sep = ' ';
898 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
899 STRTODEST(p);
900 if (*ap && sep)
901 STPUTC(sep, expdest);
902 }
903 break;
904 case '0':
905 p = arg0;
906 STRTODEST(p);
907 break;
908 default:
909 if (is_digit(*name)) {
910 num = atoi(name);
911 if (num > 0 && num <= shellparam.nparam) {
912 p = shellparam.p[num - 1];
913 STRTODEST(p);
914 }
915 }
916 break;
917 }
918}
919
920
921
922/*
923 * Record the the fact that we have to scan this region of the
924 * string for IFS characters.
925 */
926
927STATIC void
928recordregion(int start, int end, int nulonly)
929{
930 struct ifsregion *ifsp;
931
932 if (ifslastp == NULL) {
933 ifsp = &ifsfirst;
934 } else {
935 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
936 ifslastp->next = ifsp;
937 }
938 ifslastp = ifsp;
939 ifslastp->next = NULL;
940 ifslastp->begoff = start;
941 ifslastp->endoff = end;
942 ifslastp->nulonly = nulonly;
943}
944
945
946
947/*
948 * Break the argument string into pieces based upon IFS and add the
949 * strings to the argument list. The regions of the string to be
950 * searched for IFS characters have been stored by recordregion.
951 */
952STATIC void
953ifsbreakup(char *string, struct arglist *arglist)
954{
955 struct ifsregion *ifsp;
956 struct strlist *sp;
957 char *start;
958 char *p;
959 char *q;
960 char *ifs;
961 int ifsspc;
962 int nulonly;
963
964
965 start = string;
966 ifsspc = 0;
967 nulonly = 0;
968 if (ifslastp != NULL) {
969 ifsp = &ifsfirst;
970 do {
971 p = string + ifsp->begoff;
972 nulonly = ifsp->nulonly;
973 ifs = nulonly ? nullstr :
974 ( ifsset() ? ifsval() : " \t\n" );
975 ifsspc = 0;
976 while (p < string + ifsp->endoff) {
977 q = p;
978 if (*p == CTLESC)
979 p++;
980 if (strchr(ifs, *p)) {
981 if (!nulonly)
982 ifsspc = (strchr(" \t\n", *p) != NULL);
983 /* Ignore IFS whitespace at start */
984 if (q == start && ifsspc) {
985 p++;
986 start = p;
987 continue;
988 }
989 *q = '\0';
990 sp = (struct strlist *)stalloc(sizeof *sp);
991 sp->text = start;
992 *arglist->lastp = sp;
993 arglist->lastp = &sp->next;
994 p++;
995 if (!nulonly) {
996 for (;;) {
997 if (p >= string + ifsp->endoff) {
998 break;
999 }
1000 q = p;
1001 if (*p == CTLESC)
1002 p++;
1003 if (strchr(ifs, *p) == NULL ) {
1004 p = q;
1005 break;
1006 } else if (strchr(" \t\n",*p) == NULL) {
1007 if (ifsspc) {
1008 p++;
1009 ifsspc = 0;
1010 } else {
1011 p = q;
1012 break;
1013 }
1014 } else
1015 p++;
1016 }
1017 }
1018 start = p;
1019 } else
1020 p++;
1021 }
1022 } while ((ifsp = ifsp->next) != NULL);
1023 if (*start || (!ifsspc && start > string &&
1024 (nulonly || 1))) {
1025 sp = (struct strlist *)stalloc(sizeof *sp);
1026 sp->text = start;
1027 *arglist->lastp = sp;
1028 arglist->lastp = &sp->next;
1029 }
1030 } else {
1031 sp = (struct strlist *)stalloc(sizeof *sp);
1032 sp->text = start;
1033 *arglist->lastp = sp;
1034 arglist->lastp = &sp->next;
1035 }
1036}
1037
1038
1039
1040/*
1041 * Expand shell metacharacters. At this point, the only control characters
1042 * should be escapes. The results are stored in the list exparg.
1043 */
1044
1045char *expdir;
1046
1047
1048STATIC void
1049expandmeta(struct strlist *str, int flag __unused)
1050{
1051 char *p;
1052 struct strlist **savelastp;
1053 struct strlist *sp;
1054 char c;
1055 /* TODO - EXP_REDIR */
1056
1057 while (str) {
1058 if (fflag)
1059 goto nometa;
1060 p = str->text;
1061 for (;;) { /* fast check for meta chars */
1062 if ((c = *p++) == '\0')
1063 goto nometa;
1064 if (c == '*' || c == '?' || c == '[' || c == '!')
1065 break;
1066 }
1067 savelastp = exparg.lastp;
1068 INTOFF;
1069 if (expdir == NULL) {
1070 int i = strlen(str->text);
1071 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */
1072 }
1073
1074 expmeta(expdir, str->text);
1075 ckfree(expdir);
1076 expdir = NULL;
1077 INTON;
1078 if (exparg.lastp == savelastp) {
1079 /*
1080 * no matches
1081 */
1082nometa:
1083 *exparg.lastp = str;
1084 rmescapes(str->text);
1085 exparg.lastp = &str->next;
1086 } else {
1087 *exparg.lastp = NULL;
1088 *savelastp = sp = expsort(*savelastp);
1089 while (sp->next != NULL)
1090 sp = sp->next;
1091 exparg.lastp = &sp->next;
1092 }
1093 str = str->next;
1094 }
1095}
1096
1097
1098/*
1099 * Do metacharacter (i.e. *, ?, [...]) expansion.
1100 */
1101
1102STATIC void
1103expmeta(char *enddir, char *name)
1104{
1105 char *p;
1106 char *q;
1107 char *start;
1108 char *endname;
1109 int metaflag;
1110 struct stat statb;
1111 DIR *dirp;
1112 struct dirent *dp;
1113 int atend;
1114 int matchdot;
1115
1116 metaflag = 0;
1117 start = name;
1118 for (p = name ; ; p++) {
1119 if (*p == '*' || *p == '?')
1120 metaflag = 1;
1121 else if (*p == '[') {
1122 q = p + 1;
1123 if (*q == '!' || *q == '^')
1124 q++;
1125 for (;;) {
1126 while (*q == CTLQUOTEMARK)
1127 q++;
1128 if (*q == CTLESC)
1129 q++;
1130 if (*q == '/' || *q == '\0')
1131 break;
1132 if (*++q == ']') {
1133 metaflag = 1;
1134 break;
1135 }
1136 }
1137 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) {
1138 metaflag = 1;
1139 } else if (*p == '\0')
1140 break;
1141 else if (*p == CTLQUOTEMARK)
1142 continue;
1143 else if (*p == CTLESC)
1144 p++;
1145 if (*p == '/') {
1146 if (metaflag)
1147 break;
1148 start = p + 1;
1149 }
1150 }
1151 if (metaflag == 0) { /* we've reached the end of the file name */
1152 if (enddir != expdir)
1153 metaflag++;
1154 for (p = name ; ; p++) {
1155 if (*p == CTLQUOTEMARK)
1156 continue;
1157 if (*p == CTLESC)
1158 p++;
1159 *enddir++ = *p;
1160 if (*p == '\0')
1161 break;
1162 }
1163 if (metaflag == 0 || stat(expdir, &statb) >= 0)
1164 addfname(expdir);
1165 return;
1166 }
1167 endname = p;
1168 if (start != name) {
1169 p = name;
1170 while (p < start) {
1171 while (*p == CTLQUOTEMARK)
1172 p++;
1173 if (*p == CTLESC)
1174 p++;
1175 *enddir++ = *p++;
1176 }
1177 }
1178 if (enddir == expdir) {
1179 p = ".";
1180 } else if (enddir == expdir + 1 && *expdir == '/') {
1181 p = "/";
1182 } else {
1183 p = expdir;
1184 enddir[-1] = '\0';
1185 }
1186 if ((dirp = opendir(p)) == NULL)
1187 return;
1188 if (enddir != expdir)
1189 enddir[-1] = '/';
1190 if (*endname == 0) {
1191 atend = 1;
1192 } else {
1193 atend = 0;
1194 *endname++ = '\0';
1195 }
1196 matchdot = 0;
1197 p = start;
1198 while (*p == CTLQUOTEMARK)
1199 p++;
1200 if (*p == CTLESC)
1201 p++;
1202 if (*p == '.')
1203 matchdot++;
1204 while (! int_pending() && (dp = readdir(dirp)) != NULL) {
1205 if (dp->d_name[0] == '.' && ! matchdot)
1206 continue;
1207 if (patmatch(start, dp->d_name, 0)) {
1208 if (atend) {
1209 scopy(dp->d_name, enddir);
1210 addfname(expdir);
1211 } else {
1212 char *q;
1213 for (p = enddir, q = dp->d_name;
1214 (*p++ = *q++) != '\0';)
1215 continue;
1216 p[-1] = '/';
1217 expmeta(p, endname);
1218 }
1219 }
1220 }
1221 closedir(dirp);
1222 if (! atend)
1223 endname[-1] = '/';
1224}
1225
1226
1227/*
1228 * Add a file name to the list.
1229 */
1230
1231STATIC void
1232addfname(char *name)
1233{
1234 char *p;
1235 struct strlist *sp;
1236
1237 p = stalloc(strlen(name) + 1);
1238 scopy(name, p);
1239 sp = (struct strlist *)stalloc(sizeof *sp);
1240 sp->text = p;
1241 *exparg.lastp = sp;
1242 exparg.lastp = &sp->next;
1243}
1244
1245
1246/*
1247 * Sort the results of file name expansion. It calculates the number of
1248 * strings to sort and then calls msort (short for merge sort) to do the
1249 * work.
1250 */
1251
1252STATIC struct strlist *
1253expsort(struct strlist *str)
1254{
1255 int len;
1256 struct strlist *sp;
1257
1258 len = 0;
1259 for (sp = str ; sp ; sp = sp->next)
1260 len++;
1261 return msort(str, len);
1262}
1263
1264
1265STATIC struct strlist *
1266msort(struct strlist *list, int len)
1267{
1268 struct strlist *p, *q = NULL;
1269 struct strlist **lpp;
1270 int half;
1271 int n;
1272
1273 if (len <= 1)
1274 return list;
1275 half = len >> 1;
1276 p = list;
1277 for (n = half ; --n >= 0 ; ) {
1278 q = p;
1279 p = p->next;
1280 }
1281 q->next = NULL; /* terminate first half of list */
1282 q = msort(list, half); /* sort first half of list */
1283 p = msort(p, len - half); /* sort second half */
1284 lpp = &list;
1285 for (;;) {
1286 if (strcmp(p->text, q->text) < 0) {
1287 *lpp = p;
1288 lpp = &p->next;
1289 if ((p = *lpp) == NULL) {
1290 *lpp = q;
1291 break;
1292 }
1293 } else {
1294 *lpp = q;
1295 lpp = &q->next;
1296 if ((q = *lpp) == NULL) {
1297 *lpp = p;
1298 break;
1299 }
1300 }
1301 }
1302 return list;
1303}
1304
1305
1306
1307/*
1308 * Returns true if the pattern matches the string.
1309 */
1310
1311int
1312patmatch(char *pattern, char *string, int squoted)
1313{
1314#ifdef notdef
1315 if (pattern[0] == '!' && pattern[1] == '!')
1316 return 1 - pmatch(pattern + 2, string);
1317 else
1318#endif
1319 return pmatch(pattern, string, squoted);
1320}
1321
1322
1323STATIC int
1324pmatch(char *pattern, char *string, int squoted)
1325{
1326 char *p, *q;
1327 char c;
1328
1329 p = pattern;
1330 q = string;
1331 for (;;) {
1332 switch (c = *p++) {
1333 case '\0':
1334 goto breakloop;
1335 case CTLESC:
1336 if (squoted && *q == CTLESC)
1337 q++;
1338 if (*q++ != *p++)
1339 return 0;
1340 break;
1341 case CTLQUOTEMARK:
1342 continue;
1343 case '?':
1344 if (squoted && *q == CTLESC)
1345 q++;
1346 if (*q++ == '\0')
1347 return 0;
1348 break;
1349 case '*':
1350 c = *p;
1351 while (c == CTLQUOTEMARK || c == '*')
1352 c = *++p;
1353 if (c != CTLESC && c != CTLQUOTEMARK &&
1354 c != '?' && c != '*' && c != '[') {
1355 while (*q != c) {
1356 if (squoted && *q == CTLESC &&
1357 q[1] == c)
1358 break;
1359 if (*q == '\0')
1360 return 0;
1361 if (squoted && *q == CTLESC)
1362 q++;
1363 q++;
1364 }
1365 }
1366 do {
1367 if (pmatch(p, q, squoted))
1368 return 1;
1369 if (squoted && *q == CTLESC)
1370 q++;
1371 } while (*q++ != '\0');
1372 return 0;
1373 case '[': {
1374 char *endp;
1375 int invert, found;
1376 char chr;
1377
1378 endp = p;
1379 if (*endp == '!' || *endp == '^')
1380 endp++;
1381 for (;;) {
1382 while (*endp == CTLQUOTEMARK)
1383 endp++;
1384 if (*endp == '\0')
1385 goto dft; /* no matching ] */
1386 if (*endp == CTLESC)
1387 endp++;
1388 if (*++endp == ']')
1389 break;
1390 }
1391 invert = 0;
1392 if (*p == '!' || *p == '^') {
1393 invert++;
1394 p++;
1395 }
1396 found = 0;
1397 chr = *q++;
1398 if (squoted && chr == CTLESC)
1399 chr = *q++;
1400 if (chr == '\0')
1401 return 0;
1402 c = *p++;
1403 do {
1404 if (c == CTLQUOTEMARK)
1405 continue;
1406 if (c == CTLESC)
1407 c = *p++;
1408 if (*p == '-' && p[1] != ']') {
1409 p++;
1410 while (*p == CTLQUOTEMARK)
1411 p++;
1412 if (*p == CTLESC)
1413 p++;
1414 if ( collate_range_cmp(chr, c) >= 0
1415 && collate_range_cmp(chr, *p) <= 0
1416 )
1417 found = 1;
1418 p++;
1419 } else {
1420 if (chr == c)
1421 found = 1;
1422 }
1423 } while ((c = *p++) != ']');
1424 if (found == invert)
1425 return 0;
1426 break;
1427 }
1428dft: default:
1429 if (squoted && *q == CTLESC)
1430 q++;
1431 if (*q++ != c)
1432 return 0;
1433 break;
1434 }
1435 }
1436breakloop:
1437 if (*q != '\0')
1438 return 0;
1439 return 1;
1440}
1441
1442
1443
1444/*
1445 * Remove any CTLESC characters from a string.
1446 */
1447
1448void
1449rmescapes(char *str)
1450{
1451 char *p, *q;
1452
1453 p = str;
1454 while (*p != CTLESC && *p != CTLQUOTEMARK) {
1455 if (*p++ == '\0')
1456 return;
1457 }
1458 q = p;
1459 while (*p) {
1460 if (*p == CTLQUOTEMARK) {
1461 p++;
1462 continue;
1463 }
1464 if (*p == CTLESC)
1465 p++;
1466 *q++ = *p++;
1467 }
1468 *q = '\0';
1469}
1470
1471
1472
1473/*
1474 * See if a pattern matches in a case statement.
1475 */
1476
1477int
1478casematch(union node *pattern, char *val)
1479{
1480 struct stackmark smark;
1481 int result;
1482 char *p;
1483
1484 setstackmark(&smark);
1485 argbackq = pattern->narg.backquote;
1486 STARTSTACKSTR(expdest);
1487 ifslastp = NULL;
1488 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
1489 STPUTC('\0', expdest);
1490 p = grabstackstr(expdest);
1491 result = patmatch(p, val, 0);
1492 popstackmark(&smark);
1493 return result;
1494}
1495
1496/*
1497 * Our own itoa().
1498 */
1499
1500STATIC char *
1501cvtnum(int num, char *buf)
1502{
1503 char temp[32];
1504 int neg = num < 0;
1505 char *p = temp + 31;
1506
1507 temp[31] = '\0';
1508
1509 do {
1510 *--p = num % 10 + '0';
1511 } while ((num /= 10) != 0);
1512
1513 if (neg)
1514 *--p = '-';
1515
1516 while (*p)
1517 STPUTC(*p++, buf);
1518 return buf;
1519}