Contents of /trunk/mkinitrd-magellan/klibc/usr/dash/eval.c
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Fri Apr 24 18:32:46 2009 UTC (15 years, 1 month ago) by niro
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Fri Apr 24 18:32:46 2009 UTC (15 years, 1 month ago) by niro
File MIME type: text/plain
File size: 22385 byte(s)
-updated to klibc-1.5.15
1 | /*- |
2 | * Copyright (c) 1993 |
3 | * The Regents of the University of California. All rights reserved. |
4 | * Copyright (c) 1997-2005 |
5 | * Herbert Xu <herbert@gondor.apana.org.au>. All rights reserved. |
6 | * |
7 | * This code is derived from software contributed to Berkeley by |
8 | * Kenneth Almquist. |
9 | * |
10 | * Redistribution and use in source and binary forms, with or without |
11 | * modification, are permitted provided that the following conditions |
12 | * are met: |
13 | * 1. Redistributions of source code must retain the above copyright |
14 | * notice, this list of conditions and the following disclaimer. |
15 | * 2. Redistributions in binary form must reproduce the above copyright |
16 | * notice, this list of conditions and the following disclaimer in the |
17 | * documentation and/or other materials provided with the distribution. |
18 | * 3. Neither the name of the University nor the names of its contributors |
19 | * may be used to endorse or promote products derived from this software |
20 | * without specific prior written permission. |
21 | * |
22 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
23 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
24 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
25 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
26 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
27 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
28 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
29 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
30 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
31 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
32 | * SUCH DAMAGE. |
33 | */ |
34 | |
35 | #include <stdlib.h> |
36 | #include <signal.h> |
37 | #include <unistd.h> |
38 | #include <sys/types.h> |
39 | |
40 | /* |
41 | * Evaluate a command. |
42 | */ |
43 | |
44 | #include "shell.h" |
45 | #include "nodes.h" |
46 | #include "syntax.h" |
47 | #include "expand.h" |
48 | #include "parser.h" |
49 | #include "jobs.h" |
50 | #include "eval.h" |
51 | #include "builtins.h" |
52 | #include "options.h" |
53 | #include "exec.h" |
54 | #include "redir.h" |
55 | #include "input.h" |
56 | #include "output.h" |
57 | #include "trap.h" |
58 | #include "var.h" |
59 | #include "memalloc.h" |
60 | #include "error.h" |
61 | #include "show.h" |
62 | #include "mystring.h" |
63 | #ifndef SMALL |
64 | #include "myhistedit.h" |
65 | #endif |
66 | |
67 | |
68 | /* flags in argument to evaltree */ |
69 | #define EV_EXIT 01 /* exit after evaluating tree */ |
70 | #define EV_TESTED 02 /* exit status is checked; ignore -e flag */ |
71 | #define EV_BACKCMD 04 /* command executing within back quotes */ |
72 | |
73 | int evalskip; /* set if we are skipping commands */ |
74 | STATIC int skipcount; /* number of levels to skip */ |
75 | MKINIT int loopnest; /* current loop nesting level */ |
76 | static int funcnest; /* depth of function calls */ |
77 | |
78 | |
79 | char *commandname; |
80 | struct strlist *cmdenviron; |
81 | int exitstatus; /* exit status of last command */ |
82 | int back_exitstatus; /* exit status of backquoted command */ |
83 | |
84 | |
85 | #if !defined(__alpha__) || (defined(__GNUC__) && __GNUC__ >= 3) |
86 | STATIC |
87 | #endif |
88 | void evaltreenr(union node *, int) __attribute__ ((__noreturn__)); |
89 | STATIC void evalloop(union node *, int); |
90 | STATIC void evalfor(union node *, int); |
91 | STATIC void evalcase(union node *, int); |
92 | STATIC void evalsubshell(union node *, int); |
93 | STATIC void expredir(union node *); |
94 | STATIC void evalpipe(union node *, int); |
95 | #ifdef notyet |
96 | STATIC void evalcommand(union node *, int, struct backcmd *); |
97 | #else |
98 | STATIC void evalcommand(union node *, int); |
99 | #endif |
100 | STATIC int evalbltin(const struct builtincmd *, int, char **); |
101 | STATIC int evalfun(struct funcnode *, int, char **, int); |
102 | STATIC void prehash(union node *); |
103 | STATIC int eprintlist(struct output *, struct strlist *, int); |
104 | STATIC int bltincmd(int, char **); |
105 | |
106 | |
107 | STATIC const struct builtincmd bltin = { |
108 | name: nullstr, |
109 | builtin: bltincmd |
110 | }; |
111 | |
112 | |
113 | /* |
114 | * Called to reset things after an exception. |
115 | */ |
116 | |
117 | #ifdef mkinit |
118 | INCLUDE "eval.h" |
119 | |
120 | RESET { |
121 | evalskip = 0; |
122 | loopnest = 0; |
123 | } |
124 | #endif |
125 | |
126 | |
127 | |
128 | /* |
129 | * The eval commmand. |
130 | */ |
131 | |
132 | int |
133 | evalcmd(int argc, char **argv) |
134 | { |
135 | char *p; |
136 | char *concat; |
137 | char **ap; |
138 | |
139 | if (argc > 1) { |
140 | p = argv[1]; |
141 | if (argc > 2) { |
142 | STARTSTACKSTR(concat); |
143 | ap = argv + 2; |
144 | for (;;) { |
145 | concat = stputs(p, concat); |
146 | if ((p = *ap++) == NULL) |
147 | break; |
148 | STPUTC(' ', concat); |
149 | } |
150 | STPUTC('\0', concat); |
151 | p = grabstackstr(concat); |
152 | } |
153 | return evalstring(p, ~SKIPEVAL); |
154 | } |
155 | return 0; |
156 | } |
157 | |
158 | |
159 | /* |
160 | * Execute a command or commands contained in a string. |
161 | */ |
162 | |
163 | int |
164 | evalstring(char *s, int mask) |
165 | { |
166 | union node *n; |
167 | struct stackmark smark; |
168 | int status; |
169 | |
170 | setinputstring(s); |
171 | setstackmark(&smark); |
172 | |
173 | status = 0; |
174 | while ((n = parsecmd(0)) != NEOF) { |
175 | evaltree(n, 0); |
176 | status = exitstatus; |
177 | popstackmark(&smark); |
178 | if (evalskip) |
179 | break; |
180 | } |
181 | popfile(); |
182 | |
183 | evalskip &= mask; |
184 | return status; |
185 | } |
186 | |
187 | |
188 | |
189 | /* |
190 | * Evaluate a parse tree. The value is left in the global variable |
191 | * exitstatus. |
192 | */ |
193 | |
194 | void |
195 | evaltree(union node *n, int flags) |
196 | { |
197 | int checkexit = 0; |
198 | void (*evalfn)(union node *, int); |
199 | unsigned isor; |
200 | int status; |
201 | if (n == NULL) { |
202 | TRACE(("evaltree(NULL) called\n")); |
203 | goto out; |
204 | } |
205 | #ifndef SMALL |
206 | displayhist = 1; /* show history substitutions done with fc */ |
207 | #endif |
208 | TRACE(("pid %d, evaltree(%p: %d, %d) called\n", |
209 | getpid(), n, n->type, flags)); |
210 | switch (n->type) { |
211 | default: |
212 | #ifdef DEBUG |
213 | out1fmt("Node type = %d\n", n->type); |
214 | #ifndef USE_GLIBC_STDIO |
215 | flushout(out1); |
216 | #endif |
217 | break; |
218 | #endif |
219 | case NNOT: |
220 | evaltree(n->nnot.com, EV_TESTED); |
221 | status = !exitstatus; |
222 | goto setstatus; |
223 | case NREDIR: |
224 | expredir(n->nredir.redirect); |
225 | status = redirectsafe(n->nredir.redirect, REDIR_PUSH); |
226 | if (!status) { |
227 | evaltree(n->nredir.n, flags & EV_TESTED); |
228 | status = exitstatus; |
229 | } |
230 | popredir(0); |
231 | goto setstatus; |
232 | case NCMD: |
233 | #ifdef notyet |
234 | if (eflag && !(flags & EV_TESTED)) |
235 | checkexit = ~0; |
236 | evalcommand(n, flags, (struct backcmd *)NULL); |
237 | break; |
238 | #else |
239 | evalfn = evalcommand; |
240 | checkexit: |
241 | if (eflag && !(flags & EV_TESTED)) |
242 | checkexit = ~0; |
243 | goto calleval; |
244 | #endif |
245 | case NFOR: |
246 | evalfn = evalfor; |
247 | goto calleval; |
248 | case NWHILE: |
249 | case NUNTIL: |
250 | evalfn = evalloop; |
251 | goto calleval; |
252 | case NSUBSHELL: |
253 | case NBACKGND: |
254 | evalfn = evalsubshell; |
255 | goto calleval; |
256 | case NPIPE: |
257 | evalfn = evalpipe; |
258 | #ifdef notyet |
259 | if (eflag && !(flags & EV_TESTED)) |
260 | checkexit = ~0; |
261 | goto calleval; |
262 | #else |
263 | goto checkexit; |
264 | #endif |
265 | case NCASE: |
266 | evalfn = evalcase; |
267 | goto calleval; |
268 | case NAND: |
269 | case NOR: |
270 | case NSEMI: |
271 | #if NAND + 1 != NOR |
272 | #error NAND + 1 != NOR |
273 | #endif |
274 | #if NOR + 1 != NSEMI |
275 | #error NOR + 1 != NSEMI |
276 | #endif |
277 | isor = n->type - NAND; |
278 | evaltree( |
279 | n->nbinary.ch1, |
280 | (flags | ((isor >> 1) - 1)) & EV_TESTED |
281 | ); |
282 | if (!exitstatus == isor) |
283 | break; |
284 | if (!evalskip) { |
285 | n = n->nbinary.ch2; |
286 | evaln: |
287 | evalfn = evaltree; |
288 | calleval: |
289 | evalfn(n, flags); |
290 | break; |
291 | } |
292 | break; |
293 | case NIF: |
294 | evaltree(n->nif.test, EV_TESTED); |
295 | if (evalskip) |
296 | break; |
297 | if (exitstatus == 0) { |
298 | n = n->nif.ifpart; |
299 | goto evaln; |
300 | } else if (n->nif.elsepart) { |
301 | n = n->nif.elsepart; |
302 | goto evaln; |
303 | } |
304 | goto success; |
305 | case NDEFUN: |
306 | defun(n->narg.text, n->narg.next); |
307 | success: |
308 | status = 0; |
309 | setstatus: |
310 | exitstatus = status; |
311 | break; |
312 | } |
313 | out: |
314 | if ((checkexit & exitstatus)) |
315 | evalskip |= SKIPEVAL; |
316 | else if (pendingsigs && dotrap()) |
317 | goto exexit; |
318 | |
319 | if (flags & EV_EXIT) { |
320 | exexit: |
321 | exraise(EXEXIT); |
322 | } |
323 | } |
324 | |
325 | |
326 | #if !defined(__alpha__) || (defined(__GNUC__) && __GNUC__ >= 3) |
327 | STATIC |
328 | #endif |
329 | void evaltreenr(union node *, int) __attribute__ ((alias("evaltree"))); |
330 | |
331 | |
332 | STATIC void |
333 | evalloop(union node *n, int flags) |
334 | { |
335 | int status; |
336 | |
337 | loopnest++; |
338 | status = 0; |
339 | flags &= EV_TESTED; |
340 | for (;;) { |
341 | int i; |
342 | |
343 | evaltree(n->nbinary.ch1, EV_TESTED); |
344 | if (evalskip) { |
345 | skipping: if (evalskip == SKIPCONT && --skipcount <= 0) { |
346 | evalskip = 0; |
347 | continue; |
348 | } |
349 | if (evalskip == SKIPBREAK && --skipcount <= 0) |
350 | evalskip = 0; |
351 | break; |
352 | } |
353 | i = exitstatus; |
354 | if (n->type != NWHILE) |
355 | i = !i; |
356 | if (i != 0) |
357 | break; |
358 | evaltree(n->nbinary.ch2, flags); |
359 | status = exitstatus; |
360 | if (evalskip) |
361 | goto skipping; |
362 | } |
363 | loopnest--; |
364 | exitstatus = status; |
365 | } |
366 | |
367 | |
368 | |
369 | STATIC void |
370 | evalfor(union node *n, int flags) |
371 | { |
372 | struct arglist arglist; |
373 | union node *argp; |
374 | struct strlist *sp; |
375 | struct stackmark smark; |
376 | |
377 | setstackmark(&smark); |
378 | arglist.lastp = &arglist.list; |
379 | for (argp = n->nfor.args ; argp ; argp = argp->narg.next) { |
380 | expandarg(argp, &arglist, EXP_FULL | EXP_TILDE | EXP_RECORD); |
381 | /* XXX */ |
382 | if (evalskip) |
383 | goto out; |
384 | } |
385 | *arglist.lastp = NULL; |
386 | |
387 | exitstatus = 0; |
388 | loopnest++; |
389 | flags &= EV_TESTED; |
390 | for (sp = arglist.list ; sp ; sp = sp->next) { |
391 | setvar(n->nfor.var, sp->text, 0); |
392 | evaltree(n->nfor.body, flags); |
393 | if (evalskip) { |
394 | if (evalskip == SKIPCONT && --skipcount <= 0) { |
395 | evalskip = 0; |
396 | continue; |
397 | } |
398 | if (evalskip == SKIPBREAK && --skipcount <= 0) |
399 | evalskip = 0; |
400 | break; |
401 | } |
402 | } |
403 | loopnest--; |
404 | out: |
405 | popstackmark(&smark); |
406 | } |
407 | |
408 | |
409 | |
410 | STATIC void |
411 | evalcase(union node *n, int flags) |
412 | { |
413 | union node *cp; |
414 | union node *patp; |
415 | struct arglist arglist; |
416 | struct stackmark smark; |
417 | |
418 | setstackmark(&smark); |
419 | arglist.lastp = &arglist.list; |
420 | expandarg(n->ncase.expr, &arglist, EXP_TILDE); |
421 | exitstatus = 0; |
422 | for (cp = n->ncase.cases ; cp && evalskip == 0 ; cp = cp->nclist.next) { |
423 | for (patp = cp->nclist.pattern ; patp ; patp = patp->narg.next) { |
424 | if (casematch(patp, arglist.list->text)) { |
425 | if (evalskip == 0) { |
426 | evaltree(cp->nclist.body, flags); |
427 | } |
428 | goto out; |
429 | } |
430 | } |
431 | } |
432 | out: |
433 | popstackmark(&smark); |
434 | } |
435 | |
436 | |
437 | |
438 | /* |
439 | * Kick off a subshell to evaluate a tree. |
440 | */ |
441 | |
442 | STATIC void |
443 | evalsubshell(union node *n, int flags) |
444 | { |
445 | struct job *jp; |
446 | int backgnd = (n->type == NBACKGND); |
447 | int status; |
448 | |
449 | expredir(n->nredir.redirect); |
450 | if (!backgnd && flags & EV_EXIT && !trap[0]) |
451 | goto nofork; |
452 | INTOFF; |
453 | jp = makejob(n, 1); |
454 | if (forkshell(jp, n, backgnd) == 0) { |
455 | INTON; |
456 | flags |= EV_EXIT; |
457 | if (backgnd) |
458 | flags &=~ EV_TESTED; |
459 | nofork: |
460 | redirect(n->nredir.redirect, 0); |
461 | evaltreenr(n->nredir.n, flags); |
462 | /* never returns */ |
463 | } |
464 | status = 0; |
465 | if (! backgnd) |
466 | status = waitforjob(jp); |
467 | exitstatus = status; |
468 | INTON; |
469 | } |
470 | |
471 | |
472 | |
473 | /* |
474 | * Compute the names of the files in a redirection list. |
475 | */ |
476 | |
477 | STATIC void |
478 | expredir(union node *n) |
479 | { |
480 | union node *redir; |
481 | |
482 | for (redir = n ; redir ; redir = redir->nfile.next) { |
483 | struct arglist fn; |
484 | fn.lastp = &fn.list; |
485 | switch (redir->type) { |
486 | case NFROMTO: |
487 | case NFROM: |
488 | case NTO: |
489 | case NCLOBBER: |
490 | case NAPPEND: |
491 | expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR); |
492 | redir->nfile.expfname = fn.list->text; |
493 | break; |
494 | case NFROMFD: |
495 | case NTOFD: |
496 | if (redir->ndup.vname) { |
497 | expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE); |
498 | fixredir(redir, fn.list->text, 1); |
499 | } |
500 | break; |
501 | } |
502 | } |
503 | } |
504 | |
505 | |
506 | |
507 | /* |
508 | * Evaluate a pipeline. All the processes in the pipeline are children |
509 | * of the process creating the pipeline. (This differs from some versions |
510 | * of the shell, which make the last process in a pipeline the parent |
511 | * of all the rest.) |
512 | */ |
513 | |
514 | STATIC void |
515 | evalpipe(union node *n, int flags) |
516 | { |
517 | struct job *jp; |
518 | struct nodelist *lp; |
519 | int pipelen; |
520 | int prevfd; |
521 | int pip[2]; |
522 | |
523 | TRACE(("evalpipe(0x%lx) called\n", (long)n)); |
524 | pipelen = 0; |
525 | for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) |
526 | pipelen++; |
527 | flags |= EV_EXIT; |
528 | INTOFF; |
529 | jp = makejob(n, pipelen); |
530 | prevfd = -1; |
531 | for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { |
532 | prehash(lp->n); |
533 | pip[1] = -1; |
534 | if (lp->next) { |
535 | if (pipe(pip) < 0) { |
536 | close(prevfd); |
537 | sh_error("Pipe call failed"); |
538 | } |
539 | } |
540 | if (forkshell(jp, lp->n, n->npipe.backgnd) == 0) { |
541 | INTON; |
542 | if (pip[1] >= 0) { |
543 | close(pip[0]); |
544 | } |
545 | if (prevfd > 0) { |
546 | dup2(prevfd, 0); |
547 | close(prevfd); |
548 | } |
549 | if (pip[1] > 1) { |
550 | dup2(pip[1], 1); |
551 | close(pip[1]); |
552 | } |
553 | evaltreenr(lp->n, flags); |
554 | /* never returns */ |
555 | } |
556 | if (prevfd >= 0) |
557 | close(prevfd); |
558 | prevfd = pip[0]; |
559 | close(pip[1]); |
560 | } |
561 | if (n->npipe.backgnd == 0) { |
562 | exitstatus = waitforjob(jp); |
563 | TRACE(("evalpipe: job done exit status %d\n", exitstatus)); |
564 | } |
565 | INTON; |
566 | } |
567 | |
568 | |
569 | |
570 | /* |
571 | * Execute a command inside back quotes. If it's a builtin command, we |
572 | * want to save its output in a block obtained from malloc. Otherwise |
573 | * we fork off a subprocess and get the output of the command via a pipe. |
574 | * Should be called with interrupts off. |
575 | */ |
576 | |
577 | void |
578 | evalbackcmd(union node *n, struct backcmd *result) |
579 | { |
580 | int saveherefd; |
581 | |
582 | result->fd = -1; |
583 | result->buf = NULL; |
584 | result->nleft = 0; |
585 | result->jp = NULL; |
586 | if (n == NULL) { |
587 | goto out; |
588 | } |
589 | |
590 | saveherefd = herefd; |
591 | herefd = -1; |
592 | |
593 | #ifdef notyet |
594 | /* |
595 | * For now we disable executing builtins in the same |
596 | * context as the shell, because we are not keeping |
597 | * enough state to recover from changes that are |
598 | * supposed only to affect subshells. eg. echo "`cd /`" |
599 | */ |
600 | if (n->type == NCMD) { |
601 | struct ifsregion saveifs; |
602 | struct ifsregion *savelastp; |
603 | struct nodelist *saveargbackq; |
604 | |
605 | saveifs = ifsfirst; |
606 | savelastp = ifslastp; |
607 | saveargbackq = argbackq; |
608 | |
609 | exitstatus = oexitstatus; |
610 | evalcommand(n, EV_BACKCMD, result); |
611 | |
612 | ifsfirst = saveifs; |
613 | ifslastp = savelastp; |
614 | argbackq = saveargbackq; |
615 | } else |
616 | #endif |
617 | { |
618 | int pip[2]; |
619 | struct job *jp; |
620 | |
621 | if (pipe(pip) < 0) |
622 | sh_error("Pipe call failed"); |
623 | jp = makejob(n, 1); |
624 | if (forkshell(jp, n, FORK_NOJOB) == 0) { |
625 | FORCEINTON; |
626 | close(pip[0]); |
627 | if (pip[1] != 1) { |
628 | dup2(pip[1], 1); |
629 | close(pip[1]); |
630 | } |
631 | eflag = 0; |
632 | evaltreenr(n, EV_EXIT); |
633 | /* NOTREACHED */ |
634 | } |
635 | close(pip[1]); |
636 | result->fd = pip[0]; |
637 | result->jp = jp; |
638 | } |
639 | herefd = saveherefd; |
640 | out: |
641 | TRACE(("evalbackcmd done: fd=%d buf=0x%x nleft=%d jp=0x%x\n", |
642 | result->fd, result->buf, result->nleft, result->jp)); |
643 | } |
644 | |
645 | static char ** |
646 | parse_command_args(char **argv, const char **path) |
647 | { |
648 | char *cp, c; |
649 | |
650 | for (;;) { |
651 | cp = *++argv; |
652 | if (!cp) |
653 | return 0; |
654 | if (*cp++ != '-') |
655 | break; |
656 | if (!(c = *cp++)) |
657 | break; |
658 | if (c == '-' && !*cp) { |
659 | argv++; |
660 | break; |
661 | } |
662 | do { |
663 | switch (c) { |
664 | case 'p': |
665 | *path = defpath; |
666 | break; |
667 | default: |
668 | /* run 'typecmd' for other options */ |
669 | return 0; |
670 | } |
671 | } while ((c = *cp++)); |
672 | } |
673 | return argv; |
674 | } |
675 | |
676 | |
677 | |
678 | /* |
679 | * Execute a simple command. |
680 | */ |
681 | |
682 | STATIC void |
683 | #ifdef notyet |
684 | evalcommand(union node *cmd, int flags, struct backcmd *backcmd) |
685 | #else |
686 | evalcommand(union node *cmd, int flags) |
687 | #endif |
688 | { |
689 | struct stackmark smark; |
690 | union node *argp; |
691 | struct arglist arglist; |
692 | struct arglist varlist; |
693 | char **argv; |
694 | int argc; |
695 | struct strlist *sp; |
696 | #ifdef notyet |
697 | int pip[2]; |
698 | #endif |
699 | struct cmdentry cmdentry; |
700 | struct job *jp; |
701 | char *lastarg; |
702 | const char *path; |
703 | int spclbltin; |
704 | int execcmd; |
705 | int status; |
706 | char **nargv; |
707 | |
708 | /* First expand the arguments. */ |
709 | TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags)); |
710 | setstackmark(&smark); |
711 | back_exitstatus = 0; |
712 | |
713 | cmdentry.cmdtype = CMDBUILTIN; |
714 | cmdentry.u.cmd = &bltin; |
715 | varlist.lastp = &varlist.list; |
716 | *varlist.lastp = NULL; |
717 | arglist.lastp = &arglist.list; |
718 | *arglist.lastp = NULL; |
719 | |
720 | argc = 0; |
721 | for (argp = cmd->ncmd.args; argp; argp = argp->narg.next) { |
722 | struct strlist **spp; |
723 | |
724 | spp = arglist.lastp; |
725 | expandarg(argp, &arglist, EXP_FULL | EXP_TILDE); |
726 | for (sp = *spp; sp; sp = sp->next) |
727 | argc++; |
728 | } |
729 | |
730 | argv = nargv = stalloc(sizeof (char *) * (argc + 1)); |
731 | for (sp = arglist.list ; sp ; sp = sp->next) { |
732 | TRACE(("evalcommand arg: %s\n", sp->text)); |
733 | *nargv++ = sp->text; |
734 | } |
735 | *nargv = NULL; |
736 | |
737 | lastarg = NULL; |
738 | if (iflag && funcnest == 0 && argc > 0) |
739 | lastarg = nargv[-1]; |
740 | |
741 | preverrout.fd = 2; |
742 | expredir(cmd->ncmd.redirect); |
743 | status = redirectsafe(cmd->ncmd.redirect, REDIR_PUSH|REDIR_SAVEFD2); |
744 | |
745 | path = vpath.text; |
746 | for (argp = cmd->ncmd.assign; argp; argp = argp->narg.next) { |
747 | struct strlist **spp; |
748 | char *p; |
749 | |
750 | spp = varlist.lastp; |
751 | expandarg(argp, &varlist, EXP_VARTILDE); |
752 | |
753 | /* |
754 | * Modify the command lookup path, if a PATH= assignment |
755 | * is present |
756 | */ |
757 | p = (*spp)->text; |
758 | if (varequal(p, path)) |
759 | path = p; |
760 | } |
761 | |
762 | /* Print the command if xflag is set. */ |
763 | if (xflag) { |
764 | struct output *out; |
765 | int sep; |
766 | |
767 | out = &preverrout; |
768 | outstr(expandstr(ps4val()), out); |
769 | sep = 0; |
770 | sep = eprintlist(out, varlist.list, sep); |
771 | eprintlist(out, arglist.list, sep); |
772 | outcslow('\n', out); |
773 | #ifdef FLUSHERR |
774 | flushout(out); |
775 | #endif |
776 | } |
777 | |
778 | execcmd = 0; |
779 | spclbltin = -1; |
780 | |
781 | /* Now locate the command. */ |
782 | if (argc) { |
783 | const char *oldpath; |
784 | int cmd_flag = DO_ERR; |
785 | |
786 | path += 5; |
787 | oldpath = path; |
788 | for (;;) { |
789 | find_command(argv[0], &cmdentry, cmd_flag, path); |
790 | if (cmdentry.cmdtype == CMDUNKNOWN) { |
791 | status = 127; |
792 | #ifdef FLUSHERR |
793 | flushout(&errout); |
794 | #endif |
795 | goto bail; |
796 | } |
797 | |
798 | /* implement bltin and command here */ |
799 | if (cmdentry.cmdtype != CMDBUILTIN) |
800 | break; |
801 | if (spclbltin < 0) |
802 | spclbltin = |
803 | cmdentry.u.cmd->flags & |
804 | BUILTIN_SPECIAL |
805 | ; |
806 | if (cmdentry.u.cmd == EXECCMD) |
807 | execcmd++; |
808 | if (cmdentry.u.cmd != COMMANDCMD) |
809 | break; |
810 | |
811 | path = oldpath; |
812 | nargv = parse_command_args(argv, &path); |
813 | if (!nargv) |
814 | break; |
815 | argc -= nargv - argv; |
816 | argv = nargv; |
817 | cmd_flag |= DO_NOFUNC; |
818 | } |
819 | } |
820 | |
821 | if (status) { |
822 | /* We have a redirection error. */ |
823 | if (spclbltin > 0) |
824 | exraise(EXERROR); |
825 | bail: |
826 | exitstatus = status; |
827 | goto out; |
828 | } |
829 | |
830 | /* Execute the command. */ |
831 | switch (cmdentry.cmdtype) { |
832 | default: |
833 | /* Fork off a child process if necessary. */ |
834 | if (!(flags & EV_EXIT) || trap[0]) { |
835 | INTOFF; |
836 | jp = makejob(cmd, 1); |
837 | if (forkshell(jp, cmd, FORK_FG) != 0) { |
838 | exitstatus = waitforjob(jp); |
839 | INTON; |
840 | break; |
841 | } |
842 | FORCEINTON; |
843 | } |
844 | listsetvar(varlist.list, VEXPORT|VSTACK); |
845 | shellexec(argv, path, cmdentry.u.index); |
846 | /* NOTREACHED */ |
847 | |
848 | case CMDBUILTIN: |
849 | cmdenviron = varlist.list; |
850 | if (cmdenviron) { |
851 | struct strlist *list = cmdenviron; |
852 | int i = VNOSET; |
853 | if (spclbltin > 0 || argc == 0) { |
854 | i = 0; |
855 | if (execcmd && argc > 1) |
856 | i = VEXPORT; |
857 | } |
858 | listsetvar(list, i); |
859 | } |
860 | if (evalbltin(cmdentry.u.cmd, argc, argv)) { |
861 | int status; |
862 | int i, j; |
863 | |
864 | i = exception; |
865 | if (i == EXEXIT) |
866 | goto raise; |
867 | |
868 | status = 2; |
869 | j = 0; |
870 | if (i == EXINT) |
871 | j = SIGINT; |
872 | if (i == EXSIG) |
873 | j = pendingsigs; |
874 | if (j) |
875 | status = j + 128; |
876 | exitstatus = status; |
877 | |
878 | if (i == EXINT || spclbltin > 0) { |
879 | raise: |
880 | longjmp(handler->loc, 1); |
881 | } |
882 | FORCEINTON; |
883 | } |
884 | break; |
885 | |
886 | case CMDFUNCTION: |
887 | listsetvar(varlist.list, 0); |
888 | if (evalfun(cmdentry.u.func, argc, argv, flags)) |
889 | goto raise; |
890 | break; |
891 | } |
892 | |
893 | out: |
894 | popredir(execcmd); |
895 | if (lastarg) |
896 | /* dsl: I think this is intended to be used to support |
897 | * '_' in 'vi' command mode during line editing... |
898 | * However I implemented that within libedit itself. |
899 | */ |
900 | setvar("_", lastarg, 0); |
901 | popstackmark(&smark); |
902 | } |
903 | |
904 | STATIC int |
905 | evalbltin(const struct builtincmd *cmd, int argc, char **argv) { |
906 | char *volatile savecmdname; |
907 | struct jmploc *volatile savehandler; |
908 | struct jmploc jmploc; |
909 | int i; |
910 | |
911 | savecmdname = commandname; |
912 | if ((i = setjmp(jmploc.loc))) |
913 | goto cmddone; |
914 | savehandler = handler; |
915 | handler = &jmploc; |
916 | commandname = argv[0]; |
917 | argptr = argv + 1; |
918 | optptr = NULL; /* initialize nextopt */ |
919 | exitstatus = (*cmd->builtin)(argc, argv); |
920 | flushall(); |
921 | cmddone: |
922 | exitstatus |= outerr(out1); |
923 | freestdout(); |
924 | commandname = savecmdname; |
925 | exsig = 0; |
926 | handler = savehandler; |
927 | |
928 | return i; |
929 | } |
930 | |
931 | STATIC int |
932 | evalfun(struct funcnode *func, int argc, char **argv, int flags) |
933 | { |
934 | volatile struct shparam saveparam; |
935 | struct localvar *volatile savelocalvars; |
936 | struct jmploc *volatile savehandler; |
937 | struct jmploc jmploc; |
938 | int e; |
939 | |
940 | saveparam = shellparam; |
941 | savelocalvars = localvars; |
942 | if ((e = setjmp(jmploc.loc))) { |
943 | goto funcdone; |
944 | } |
945 | INTOFF; |
946 | savehandler = handler; |
947 | handler = &jmploc; |
948 | localvars = NULL; |
949 | shellparam.malloc = 0; |
950 | func->count++; |
951 | funcnest++; |
952 | INTON; |
953 | shellparam.nparam = argc - 1; |
954 | shellparam.p = argv + 1; |
955 | shellparam.optind = 1; |
956 | shellparam.optoff = -1; |
957 | evaltree(&func->n, flags & EV_TESTED); |
958 | funcdone: |
959 | INTOFF; |
960 | funcnest--; |
961 | freefunc(func); |
962 | poplocalvars(); |
963 | localvars = savelocalvars; |
964 | freeparam(&shellparam); |
965 | shellparam = saveparam; |
966 | handler = savehandler; |
967 | INTON; |
968 | evalskip &= ~SKIPFUNC; |
969 | return e; |
970 | } |
971 | |
972 | |
973 | /* |
974 | * Search for a command. This is called before we fork so that the |
975 | * location of the command will be available in the parent as well as |
976 | * the child. The check for "goodname" is an overly conservative |
977 | * check that the name will not be subject to expansion. |
978 | */ |
979 | |
980 | STATIC void |
981 | prehash(union node *n) |
982 | { |
983 | struct cmdentry entry; |
984 | |
985 | if (n->type == NCMD && n->ncmd.args) |
986 | if (goodname(n->ncmd.args->narg.text)) |
987 | find_command(n->ncmd.args->narg.text, &entry, 0, |
988 | pathval()); |
989 | } |
990 | |
991 | |
992 | |
993 | /* |
994 | * Builtin commands. Builtin commands whose functions are closely |
995 | * tied to evaluation are implemented here. |
996 | */ |
997 | |
998 | /* |
999 | * No command given. |
1000 | */ |
1001 | |
1002 | STATIC int |
1003 | bltincmd(int argc, char **argv) |
1004 | { |
1005 | /* |
1006 | * Preserve exitstatus of a previous possible redirection |
1007 | * as POSIX mandates |
1008 | */ |
1009 | return back_exitstatus; |
1010 | } |
1011 | |
1012 | |
1013 | /* |
1014 | * Handle break and continue commands. Break, continue, and return are |
1015 | * all handled by setting the evalskip flag. The evaluation routines |
1016 | * above all check this flag, and if it is set they start skipping |
1017 | * commands rather than executing them. The variable skipcount is |
1018 | * the number of loops to break/continue, or the number of function |
1019 | * levels to return. (The latter is always 1.) It should probably |
1020 | * be an error to break out of more loops than exist, but it isn't |
1021 | * in the standard shell so we don't make it one here. |
1022 | */ |
1023 | |
1024 | int |
1025 | breakcmd(int argc, char **argv) |
1026 | { |
1027 | int n = argc > 1 ? number(argv[1]) : 1; |
1028 | |
1029 | if (n <= 0) |
1030 | sh_error(illnum, argv[1]); |
1031 | if (n > loopnest) |
1032 | n = loopnest; |
1033 | if (n > 0) { |
1034 | evalskip = (**argv == 'c')? SKIPCONT : SKIPBREAK; |
1035 | skipcount = n; |
1036 | } |
1037 | return 0; |
1038 | } |
1039 | |
1040 | |
1041 | /* |
1042 | * The return command. |
1043 | */ |
1044 | |
1045 | int |
1046 | returncmd(int argc, char **argv) |
1047 | { |
1048 | /* |
1049 | * If called outside a function, do what ksh does; |
1050 | * skip the rest of the file. |
1051 | */ |
1052 | evalskip = funcnest ? SKIPFUNC : SKIPFILE; |
1053 | return argv[1] ? number(argv[1]) : exitstatus; |
1054 | } |
1055 | |
1056 | |
1057 | int |
1058 | falsecmd(int argc, char **argv) |
1059 | { |
1060 | return 1; |
1061 | } |
1062 | |
1063 | |
1064 | int |
1065 | truecmd(int argc, char **argv) |
1066 | { |
1067 | return 0; |
1068 | } |
1069 | |
1070 | |
1071 | int |
1072 | execcmd(int argc, char **argv) |
1073 | { |
1074 | if (argc > 1) { |
1075 | iflag = 0; /* exit on error */ |
1076 | mflag = 0; |
1077 | optschanged(); |
1078 | shellexec(argv + 1, pathval(), 0); |
1079 | } |
1080 | return 0; |
1081 | } |
1082 | |
1083 | |
1084 | STATIC int |
1085 | eprintlist(struct output *out, struct strlist *sp, int sep) |
1086 | { |
1087 | while (sp) { |
1088 | const char *p; |
1089 | |
1090 | p = " %s" + (1 - sep); |
1091 | sep |= 1; |
1092 | outfmt(out, p, sp->text); |
1093 | sp = sp->next; |
1094 | } |
1095 | |
1096 | return sep; |
1097 | } |