exp.c revision 1.13 1 /* $NetBSD: exp.c,v 1.13 2002/05/25 23:29:16 wiz Exp $ */
2
3 /*-
4 * Copyright (c) 1980, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)exp.c 8.1 (Berkeley) 5/31/93";
40 #else
41 __RCSID("$NetBSD: exp.c,v 1.13 2002/05/25 23:29:16 wiz Exp $");
42 #endif
43 #endif /* not lint */
44
45 #include <sys/types.h>
46 #include <sys/stat.h>
47
48 #include <stdarg.h>
49 #include <stdlib.h>
50 #include <unistd.h>
51
52 #ifndef SHORT_STRINGS
53 #include <string.h>
54 #endif /* SHORT_STRINGS */
55
56 #include "csh.h"
57 #include "extern.h"
58
59 #define IGNORE 1 /* in ignore, it means to ignore value, just parse */
60 #define NOGLOB 2 /* in ignore, it means not to globone */
61
62 #define ADDOP 1
63 #define MULOP 2
64 #define EQOP 4
65 #define RELOP 8
66 #define RESTOP 16
67 #define ANYOP 31
68
69 #define EQEQ 1
70 #define GTR 2
71 #define LSS 4
72 #define NOTEQ 6
73 #define EQMATCH 7
74 #define NOTEQMATCH 8
75
76 static int exp1(Char ***, bool);
77 static int exp2(Char ***, bool);
78 static int exp2a(Char ***, bool);
79 static int exp2b(Char ***, bool);
80 static int exp2c(Char ***, bool);
81 static Char *exp3(Char ***, bool);
82 static Char *exp3a(Char ***, bool);
83 static Char *exp4(Char ***, bool);
84 static Char *exp5(Char ***, bool);
85 static Char *exp6(Char ***, bool);
86 static void evalav(Char **);
87 static int isa(Char *, int);
88 static int egetn(Char *);
89
90 #ifdef EDEBUG
91 static void etracc(char *, Char *, Char ***);
92 static void etraci(char *, int, Char ***);
93 #endif
94
95 int
96 expr(Char ***vp)
97 {
98 return (exp0(vp, 0));
99 }
100
101 int
102 exp0(Char ***vp, bool ignore)
103 {
104 int p1;
105
106 p1 = exp1(vp, ignore);
107 #ifdef EDEBUG
108 etraci("exp0 p1", p1, vp);
109 #endif
110 if (**vp && eq(**vp, STRor2)) {
111 int p2;
112
113 (*vp)++;
114 p2 = exp0(vp, (ignore & IGNORE) || p1);
115 #ifdef EDEBUG
116 etraci("exp0 p2", p2, vp);
117 #endif
118 return (p1 || p2);
119 }
120 return (p1);
121 }
122
123 static int
124 exp1(Char ***vp, bool ignore)
125 {
126 int p1;
127
128 p1 = exp2(vp, ignore);
129 #ifdef EDEBUG
130 etraci("exp1 p1", p1, vp);
131 #endif
132 if (**vp && eq(**vp, STRand2)) {
133 int p2;
134
135 (*vp)++;
136 p2 = exp1(vp, (ignore & IGNORE) || !p1);
137 #ifdef EDEBUG
138 etraci("exp1 p2", p2, vp);
139 #endif
140 return (p1 && p2);
141 }
142 return (p1);
143 }
144
145 static int
146 exp2(Char ***vp, bool ignore)
147 {
148 int p1;
149
150 p1 = exp2a(vp, ignore);
151 #ifdef EDEBUG
152 etraci("exp3 p1", p1, vp);
153 #endif
154 if (**vp && eq(**vp, STRor)) {
155 int p2;
156
157 (*vp)++;
158 p2 = exp2(vp, ignore);
159 #ifdef EDEBUG
160 etraci("exp3 p2", p2, vp);
161 #endif
162 return (p1 | p2);
163 }
164 return (p1);
165 }
166
167 static int
168 exp2a(Char ***vp, bool ignore)
169 {
170 int p1;
171
172 p1 = exp2b(vp, ignore);
173 #ifdef EDEBUG
174 etraci("exp2a p1", p1, vp);
175 #endif
176 if (**vp && eq(**vp, STRcaret)) {
177 int p2;
178
179 (*vp)++;
180 p2 = exp2a(vp, ignore);
181 #ifdef EDEBUG
182 etraci("exp2a p2", p2, vp);
183 #endif
184 return (p1 ^ p2);
185 }
186 return (p1);
187 }
188
189 static int
190 exp2b(Char ***vp, bool ignore)
191 {
192 int p1;
193
194 p1 = exp2c(vp, ignore);
195 #ifdef EDEBUG
196 etraci("exp2b p1", p1, vp);
197 #endif
198 if (**vp && eq(**vp, STRand)) {
199 int p2;
200
201 (*vp)++;
202 p2 = exp2b(vp, ignore);
203 #ifdef EDEBUG
204 etraci("exp2b p2", p2, vp);
205 #endif
206 return (p1 & p2);
207 }
208 return (p1);
209 }
210
211 static int
212 exp2c(Char ***vp, bool ignore)
213 {
214 Char *p1, *p2;
215 int i;
216
217 p1 = exp3(vp, ignore);
218 #ifdef EDEBUG
219 etracc("exp2c p1", p1, vp);
220 #endif
221 if ((i = isa(**vp, EQOP)) != 0) {
222 (*vp)++;
223 if (i == EQMATCH || i == NOTEQMATCH)
224 ignore |= NOGLOB;
225 p2 = exp3(vp, ignore);
226 #ifdef EDEBUG
227 etracc("exp2c p2", p2, vp);
228 #endif
229 if (!(ignore & IGNORE))
230 switch (i) {
231 case EQEQ:
232 i = eq(p1, p2);
233 break;
234 case EQMATCH:
235 i = Gmatch(p1, p2);
236 break;
237 case NOTEQ:
238 i = !eq(p1, p2);
239 break;
240 case NOTEQMATCH:
241 i = !Gmatch(p1, p2);
242 break;
243 }
244 xfree((ptr_t) p1);
245 xfree((ptr_t) p2);
246 return (i);
247 }
248 i = egetn(p1);
249 xfree((ptr_t) p1);
250 return (i);
251 }
252
253 static Char *
254 exp3(Char ***vp, bool ignore)
255 {
256 Char *p1, *p2;
257 int i;
258
259 p1 = exp3a(vp, ignore);
260 #ifdef EDEBUG
261 etracc("exp3 p1", p1, vp);
262 #endif
263 if ((i = isa(**vp, RELOP)) != 0) {
264 (*vp)++;
265 if (**vp && eq(**vp, STRequal))
266 i |= 1, (*vp)++;
267 p2 = exp3(vp, ignore);
268 #ifdef EDEBUG
269 etracc("exp3 p2", p2, vp);
270 #endif
271 if (!(ignore & IGNORE))
272 switch (i) {
273 case GTR:
274 i = egetn(p1) > egetn(p2);
275 break;
276 case GTR | 1:
277 i = egetn(p1) >= egetn(p2);
278 break;
279 case LSS:
280 i = egetn(p1) < egetn(p2);
281 break;
282 case LSS | 1:
283 i = egetn(p1) <= egetn(p2);
284 break;
285 }
286 xfree((ptr_t) p1);
287 xfree((ptr_t) p2);
288 return (putn(i));
289 }
290 return (p1);
291 }
292
293 static Char *
294 exp3a(Char ***vp, bool ignore)
295 {
296 Char *op, *p1, *p2;
297 int i;
298
299 p1 = exp4(vp, ignore);
300 #ifdef EDEBUG
301 etracc("exp3a p1", p1, vp);
302 #endif
303 op = **vp;
304 if (op && any("<>", op[0]) && op[0] == op[1]) {
305 (*vp)++;
306 p2 = exp3a(vp, ignore);
307 #ifdef EDEBUG
308 etracc("exp3a p2", p2, vp);
309 #endif
310 if (op[0] == '<')
311 i = egetn(p1) << egetn(p2);
312 else
313 i = egetn(p1) >> egetn(p2);
314 xfree((ptr_t) p1);
315 xfree((ptr_t) p2);
316 return (putn(i));
317 }
318 return (p1);
319 }
320
321 static Char *
322 exp4(Char ***vp, bool ignore)
323 {
324 Char *p1, *p2;
325 int i;
326
327 i = 0;
328 p1 = exp5(vp, ignore);
329 #ifdef EDEBUG
330 etracc("exp4 p1", p1, vp);
331 #endif
332 if (isa(**vp, ADDOP)) {
333 Char *op;
334
335 op = *(*vp)++;
336 p2 = exp4(vp, ignore);
337 #ifdef EDEBUG
338 etracc("exp4 p2", p2, vp);
339 #endif
340 if (!(ignore & IGNORE))
341 switch (op[0]) {
342 case '+':
343 i = egetn(p1) + egetn(p2);
344 break;
345 case '-':
346 i = egetn(p1) - egetn(p2);
347 break;
348 }
349 xfree((ptr_t) p1);
350 xfree((ptr_t) p2);
351 return (putn(i));
352 }
353 return (p1);
354 }
355
356 static Char *
357 exp5(Char ***vp, bool ignore)
358 {
359 Char *p1, *p2;
360 int i;
361
362 i = 0;
363 p1 = exp6(vp, ignore);
364 #ifdef EDEBUG
365 etracc("exp5 p1", p1, vp);
366 #endif
367 if (isa(**vp, MULOP)) {
368 Char *op;
369
370 op = *(*vp)++;
371 p2 = exp5(vp, ignore);
372 #ifdef EDEBUG
373 etracc("exp5 p2", p2, vp);
374 #endif
375 if (!(ignore & IGNORE))
376 switch (op[0]) {
377 case '*':
378 i = egetn(p1) * egetn(p2);
379 break;
380 case '/':
381 i = egetn(p2);
382 if (i == 0)
383 stderror(ERR_DIV0);
384 i = egetn(p1) / i;
385 break;
386 case '%':
387 i = egetn(p2);
388 if (i == 0)
389 stderror(ERR_MOD0);
390 i = egetn(p1) % i;
391 break;
392 }
393 xfree((ptr_t) p1);
394 xfree((ptr_t) p2);
395 return (putn(i));
396 }
397 return (p1);
398 }
399
400 static Char *
401 exp6(Char ***vp, bool ignore)
402 {
403 Char *cp, *dp, *ep;
404 int ccode, i;
405
406 i = 0;
407 if (**vp == 0)
408 stderror(ERR_NAME | ERR_EXPRESSION);
409 if (eq(**vp, STRbang)) {
410 (*vp)++;
411 cp = exp6(vp, ignore);
412 #ifdef EDEBUG
413 etracc("exp6 ! cp", cp, vp);
414 #endif
415 i = egetn(cp);
416 xfree((ptr_t) cp);
417 return (putn(!i));
418 }
419 if (eq(**vp, STRtilde)) {
420 (*vp)++;
421 cp = exp6(vp, ignore);
422 #ifdef EDEBUG
423 etracc("exp6 ~ cp", cp, vp);
424 #endif
425 i = egetn(cp);
426 xfree((ptr_t) cp);
427 return (putn(~i));
428 }
429 if (eq(**vp, STRLparen)) {
430 (*vp)++;
431 ccode = exp0(vp, ignore);
432 #ifdef EDEBUG
433 etraci("exp6 () ccode", ccode, vp);
434 #endif
435 if (*vp == 0 || **vp == 0 || ***vp != ')')
436 stderror(ERR_NAME | ERR_EXPRESSION);
437 (*vp)++;
438 return (putn(ccode));
439 }
440 if (eq(**vp, STRLbrace)) {
441 struct command faket;
442 Char *fakecom[2];
443 Char **v;
444
445 faket.t_dtyp = NODE_COMMAND;
446 faket.t_dflg = 0;
447 faket.t_dcar = faket.t_dcdr = faket.t_dspr = NULL;
448 faket.t_dcom = fakecom;
449 fakecom[0] = STRfakecom;
450 fakecom[1] = NULL;
451 (*vp)++;
452 v = *vp;
453 for (;;) {
454 if (!**vp)
455 stderror(ERR_NAME | ERR_MISSING, '}');
456 if (eq(*(*vp)++, STRRbrace))
457 break;
458 }
459 if (ignore & IGNORE)
460 return (Strsave(STRNULL));
461 psavejob();
462 if (pfork(&faket, -1) == 0) {
463 *--(*vp) = 0;
464 evalav(v);
465 exitstat();
466 }
467 pwait();
468 prestjob();
469 #ifdef EDEBUG
470 etraci("exp6 {} status", egetn(value(STRstatus)), vp);
471 #endif
472 return (putn(egetn(value(STRstatus)) == 0));
473 }
474 if (isa(**vp, ANYOP))
475 return (Strsave(STRNULL));
476 cp = *(*vp)++;
477 if (*cp == '-' && any("erwxfdzopls", cp[1])) {
478 struct stat stb;
479
480 if (cp[2] != '\0')
481 stderror(ERR_NAME | ERR_FILEINQ);
482 /*
483 * Detect missing file names by checking for operator in the file name
484 * position. However, if an operator name appears there, we must make
485 * sure that there's no file by that name (e.g., "/") before announcing
486 * an error. Even this check isn't quite right, since it doesn't take
487 * globbing into account.
488 */
489 if (isa(**vp, ANYOP) && stat(short2str(**vp), &stb))
490 stderror(ERR_NAME | ERR_FILENAME);
491
492 dp = *(*vp)++;
493 if (ignore & IGNORE)
494 return (Strsave(STRNULL));
495 ep = globone(dp, G_ERROR);
496 switch (cp[1]) {
497 case 'r':
498 i = !access(short2str(ep), R_OK);
499 break;
500 case 'w':
501 i = !access(short2str(ep), W_OK);
502 break;
503 case 'x':
504 i = !access(short2str(ep), X_OK);
505 break;
506 default:
507 if (cp[1] == 'l' ?
508 lstat(short2str(ep), &stb) : stat(short2str(ep), &stb)) {
509 xfree((ptr_t) ep);
510 return (Strsave(STR0));
511 }
512 switch (cp[1]) {
513 case 'd':
514 i = S_ISDIR(stb.st_mode);
515 break;
516 case 'e':
517 i = 1;
518 break;
519 case 'f':
520 i = S_ISREG(stb.st_mode);
521 break;
522 case 'l':
523 #ifdef S_ISLNK
524 i = S_ISLNK(stb.st_mode);
525 #else
526 i = 0;
527 #endif
528 break;
529 case 'o':
530 i = stb.st_uid == uid;
531 break;
532 case 'p':
533 #ifdef S_ISFIFO
534 i = S_ISFIFO(stb.st_mode);
535 #else
536 i = 0;
537 #endif
538 break;
539 case 's':
540 #ifdef S_ISSOCK
541 i = S_ISSOCK(stb.st_mode);
542 #else
543 i = 0;
544 #endif
545 break;
546 case 'z':
547 i = stb.st_size == 0;
548 break;
549 }
550 }
551 #ifdef EDEBUG
552 etraci("exp6 -? i", i, vp);
553 #endif
554 xfree((ptr_t) ep);
555 return (putn(i));
556 }
557 #ifdef EDEBUG
558 etracc("exp6 default", cp, vp);
559 #endif
560 return (ignore & NOGLOB ? Strsave(cp) : globone(cp, G_ERROR));
561 }
562
563 static void
564 evalav(Char **v)
565 {
566 struct wordent *hp, paraml1, *wdp;
567 struct command *t;
568
569 hp = ¶ml1;
570 wdp = hp;
571 set(STRstatus, Strsave(STR0));
572 hp->prev = hp->next = hp;
573 hp->word = STRNULL;
574 while (*v) {
575 struct wordent *new;
576
577 new = (struct wordent *)xcalloc(1, sizeof *wdp);
578 new->prev = wdp;
579 new->next = hp;
580 wdp->next = new;
581 wdp = new;
582 wdp->word = Strsave(*v++);
583 }
584 hp->prev = wdp;
585 alias(¶ml1);
586 t = syntax(paraml1.next, ¶ml1, 0);
587 if (seterr)
588 stderror(ERR_OLD);
589 execute(t, -1, NULL, NULL);
590 freelex(¶ml1), freesyn(t);
591 }
592
593 static int
594 isa(Char *cp, int what)
595 {
596 if (cp == 0)
597 return ((what & RESTOP) != 0);
598 if (cp[1] == 0) {
599 if (what & ADDOP && (*cp == '+' || *cp == '-'))
600 return (1);
601 if (what & MULOP && (*cp == '*' || *cp == '/' || *cp == '%'))
602 return (1);
603 if (what & RESTOP && (*cp == '(' || *cp == ')' || *cp == '!' ||
604 *cp == '~' || *cp == '^' || *cp == '"'))
605 return (1);
606 }
607 else if (cp[2] == 0) {
608 if (what & RESTOP) {
609 if (cp[0] == '|' && cp[1] == '&')
610 return (1);
611 if (cp[0] == '<' && cp[1] == '<')
612 return (1);
613 if (cp[0] == '>' && cp[1] == '>')
614 return (1);
615 }
616 if (what & EQOP) {
617 if (cp[0] == '=') {
618 if (cp[1] == '=')
619 return (EQEQ);
620 if (cp[1] == '~')
621 return (EQMATCH);
622 }
623 else if (cp[0] == '!') {
624 if (cp[1] == '=')
625 return (NOTEQ);
626 if (cp[1] == '~')
627 return (NOTEQMATCH);
628 }
629 }
630 }
631 if (what & RELOP) {
632 if (*cp == '<')
633 return (LSS);
634 if (*cp == '>')
635 return (GTR);
636 }
637 return (0);
638 }
639
640 static int
641 egetn(Char *cp)
642 {
643 if (*cp && *cp != '-' && !Isdigit(*cp))
644 stderror(ERR_NAME | ERR_EXPRESSION);
645 return (getn(cp));
646 }
647
648 /* Phew! */
649
650 #ifdef EDEBUG
651 static void
652 etraci(char *str, int i, Char ***vp)
653 {
654 (void)fprintf(csherr, "%s=%d\t", str, i);
655 blkpr(csherr, *vp);
656 (void)fprintf(csherr, "\n");
657 }
658 static void
659 etracc(char *str, Char *cp, Char ***vp)
660 {
661 (void)fprintf(csherr, "%s=%s\t", str, vis_str(cp));
662 blkpr(csherr, *vp);
663 (void)fprintf(csherr, "\n");
664 }
665 #endif
666