sh: Add $'quoting' (C-style escape sequences).
[dragonfly.git] / bin / sh / parser.c
CommitLineData
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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 * @(#)parser.c 8.7 (Berkeley) 5/16/95
e1489450 37 * $FreeBSD: src/bin/sh/parser.c,v 1.109 2011/05/05 20:55:55 jilles Exp $
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38 */
39
a276dc6b 40#include <stdio.h>
984263bc 41#include <stdlib.h>
3c79a5ea 42#include <unistd.h>
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43
44#include "shell.h"
45#include "parser.h"
46#include "nodes.h"
47#include "expand.h" /* defines rmescapes() */
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48#include "syntax.h"
49#include "options.h"
50#include "input.h"
51#include "output.h"
52#include "var.h"
53#include "error.h"
54#include "memalloc.h"
55#include "mystring.h"
56#include "alias.h"
57#include "show.h"
58#include "eval.h"
99512ac4 59#include "exec.h" /* to check for special builtins */
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60#ifndef NO_HISTORY
61#include "myhistedit.h"
62#endif
63
64/*
65 * Shell command parser.
66 */
67
3c79a5ea
PA
68#define EOFMARKLEN 79
69#define PROMPTLEN 128
984263bc 70
99512ac4
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71/* values of checkkwd variable */
72#define CHKALIAS 0x1
73#define CHKKWD 0x2
74#define CHKNL 0x4
75
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76/* values returned by readtoken */
77#include "token.h"
78
79
80
81struct heredoc {
82 struct heredoc *next; /* next here document in list */
83 union node *here; /* redirection node */
84 char *eofmark; /* string indicating end of input */
85 int striptabs; /* if set, strip leading tabs */
86};
87
99512ac4
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88struct parser_temp {
89 struct parser_temp *next;
90 void *data;
91};
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92
93
99512ac4
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94static struct heredoc *heredoclist; /* list of here documents to read */
95static int doprompt; /* if set, prompt the user */
96static int needprompt; /* true if interactive and at start of line */
97static int lasttoken; /* last token read */
984263bc 98MKINIT int tokpushback; /* last token pushed back */
99512ac4
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99static char *wordtext; /* text of last word returned by readtoken */
100MKINIT int checkkwd; /* 1 == check for kwds, 2 == also eat newlines */
101static struct nodelist *backquotelist;
102static union node *redirnode;
103static struct heredoc *heredoc;
104static int quoteflag; /* set if (part of) last token was quoted */
105static int startlinno; /* line # where last token started */
106static int funclinno; /* line # where the current function started */
107static struct parser_temp *parser_temp;
108
109
110static union node *list(int, int);
111static union node *andor(void);
112static union node *pipeline(void);
113static union node *command(void);
114static union node *simplecmd(union node **, union node *);
115static union node *makename(void);
116static void parsefname(void);
117static void parseheredoc(void);
118static int peektoken(void);
119static int readtoken(void);
120static int xxreadtoken(void);
121static int readtoken1(int, char const *, char *, int);
122static int noexpand(char *);
123static void synexpect(int) __dead2;
124static void synerror(const char *) __dead2;
125static void setprompt(int);
126
127
128static void *
129parser_temp_alloc(size_t len)
130{
131 struct parser_temp *t;
132
133 INTOFF;
134 t = ckmalloc(sizeof(*t));
135 t->data = NULL;
136 t->next = parser_temp;
137 parser_temp = t;
138 t->data = ckmalloc(len);
139 INTON;
140 return t->data;
141}
142
143
144static void *
145parser_temp_realloc(void *ptr, size_t len)
146{
147 struct parser_temp *t;
148
149 INTOFF;
150 t = parser_temp;
151 if (ptr != t->data)
152 error("bug: parser_temp_realloc misused");
153 t->data = ckrealloc(t->data, len);
154 INTON;
155 return t->data;
156}
157
158
159static void
160parser_temp_free_upto(void *ptr)
161{
162 struct parser_temp *t;
163 int done = 0;
164
165 INTOFF;
166 while (parser_temp != NULL && !done) {
167 t = parser_temp;
168 parser_temp = t->next;
169 done = t->data == ptr;
170 ckfree(t->data);
171 ckfree(t);
172 }
173 INTON;
174 if (!done)
175 error("bug: parser_temp_free_upto misused");
176}
177
178
179static void
180parser_temp_free_all(void)
181{
182 struct parser_temp *t;
183
184 INTOFF;
185 while (parser_temp != NULL) {
186 t = parser_temp;
187 parser_temp = t->next;
188 ckfree(t->data);
189 ckfree(t);
190 }
191 INTON;
192}
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193
194
195/*
196 * Read and parse a command. Returns NEOF on end of file. (NULL is a
197 * valid parse tree indicating a blank line.)
198 */
199
200union node *
201parsecmd(int interact)
202{
203 int t;
204
99512ac4
PA
205 /* This assumes the parser is not re-entered,
206 * which could happen if we add command substitution on PS1/PS2.
207 */
208 parser_temp_free_all();
209 heredoclist = NULL;
210
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211 tokpushback = 0;
212 doprompt = interact;
213 if (doprompt)
214 setprompt(1);
215 else
216 setprompt(0);
217 needprompt = 0;
218 t = readtoken();
219 if (t == TEOF)
220 return NEOF;
221 if (t == TNL)
222 return NULL;
223 tokpushback++;
99512ac4 224 return list(1, 1);
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225}
226
227
99512ac4
PA
228static union node *
229list(int nlflag, int erflag)
984263bc 230{
99512ac4 231 union node *ntop, *n1, *n2, *n3;
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232 int tok;
233
99512ac4
PA
234 checkkwd = CHKNL | CHKKWD | CHKALIAS;
235 if (!nlflag && !erflag && tokendlist[peektoken()])
984263bc 236 return NULL;
99512ac4 237 ntop = n1 = NULL;
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238 for (;;) {
239 n2 = andor();
240 tok = readtoken();
241 if (tok == TBACKGND) {
242 if (n2->type == NCMD || n2->type == NPIPE) {
243 n2->ncmd.backgnd = 1;
244 } else if (n2->type == NREDIR) {
245 n2->type = NBACKGND;
246 } else {
247 n3 = (union node *)stalloc(sizeof (struct nredir));
248 n3->type = NBACKGND;
249 n3->nredir.n = n2;
250 n3->nredir.redirect = NULL;
251 n2 = n3;
252 }
253 }
99512ac4
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254 if (ntop == NULL)
255 ntop = n2;
256 else if (n1 == NULL) {
257 n1 = (union node *)stalloc(sizeof (struct nbinary));
258 n1->type = NSEMI;
259 n1->nbinary.ch1 = ntop;
260 n1->nbinary.ch2 = n2;
261 ntop = n1;
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262 }
263 else {
264 n3 = (union node *)stalloc(sizeof (struct nbinary));
265 n3->type = NSEMI;
99512ac4 266 n3->nbinary.ch1 = n1->nbinary.ch2;
984263bc 267 n3->nbinary.ch2 = n2;
99512ac4 268 n1->nbinary.ch2 = n3;
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269 n1 = n3;
270 }
271 switch (tok) {
272 case TBACKGND:
273 case TSEMI:
274 tok = readtoken();
3c79a5ea 275 /* FALLTHROUGH */
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276 case TNL:
277 if (tok == TNL) {
278 parseheredoc();
279 if (nlflag)
99512ac4
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280 return ntop;
281 } else if (tok == TEOF && nlflag) {
282 parseheredoc();
283 return ntop;
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284 } else {
285 tokpushback++;
286 }
99512ac4
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287 checkkwd = CHKNL | CHKKWD | CHKALIAS;
288 if (!nlflag && !erflag && tokendlist[peektoken()])
289 return ntop;
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290 break;
291 case TEOF:
292 if (heredoclist)
293 parseheredoc();
294 else
295 pungetc(); /* push back EOF on input */
99512ac4 296 return ntop;
984263bc 297 default:
99512ac4 298 if (nlflag || erflag)
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299 synexpect(-1);
300 tokpushback++;
99512ac4 301 return ntop;
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302 }
303 }
304}
305
306
307
99512ac4 308static union node *
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309andor(void)
310{
311 union node *n1, *n2, *n3;
312 int t;
313
314 n1 = pipeline();
315 for (;;) {
316 if ((t = readtoken()) == TAND) {
317 t = NAND;
318 } else if (t == TOR) {
319 t = NOR;
320 } else {
321 tokpushback++;
322 return n1;
323 }
324 n2 = pipeline();
325 n3 = (union node *)stalloc(sizeof (struct nbinary));
326 n3->type = t;
327 n3->nbinary.ch1 = n1;
328 n3->nbinary.ch2 = n2;
329 n1 = n3;
330 }
331}
332
333
334
99512ac4 335static union node *
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336pipeline(void)
337{
338 union node *n1, *n2, *pipenode;
339 struct nodelist *lp, *prev;
99512ac4 340 int negate, t;
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341
342 negate = 0;
99512ac4 343 checkkwd = CHKNL | CHKKWD | CHKALIAS;
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344 TRACE(("pipeline: entered\n"));
345 while (readtoken() == TNOT)
346 negate = !negate;
347 tokpushback++;
348 n1 = command();
349 if (readtoken() == TPIPE) {
350 pipenode = (union node *)stalloc(sizeof (struct npipe));
351 pipenode->type = NPIPE;
352 pipenode->npipe.backgnd = 0;
353 lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
354 pipenode->npipe.cmdlist = lp;
355 lp->n = n1;
356 do {
357 prev = lp;
358 lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
99512ac4
PA
359 checkkwd = CHKNL | CHKKWD | CHKALIAS;
360 t = readtoken();
361 tokpushback++;
362 if (t == TNOT)
363 lp->n = pipeline();
364 else
365 lp->n = command();
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366 prev->next = lp;
367 } while (readtoken() == TPIPE);
368 lp->next = NULL;
369 n1 = pipenode;
370 }
371 tokpushback++;
372 if (negate) {
373 n2 = (union node *)stalloc(sizeof (struct nnot));
374 n2->type = NNOT;
375 n2->nnot.com = n1;
376 return n2;
377 } else
378 return n1;
379}
380
381
382
99512ac4 383static union node *
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384command(void)
385{
386 union node *n1, *n2;
387 union node *ap, **app;
388 union node *cp, **cpp;
389 union node *redir, **rpp;
5c454bc1 390 int t;
99512ac4 391 int is_subshell;
984263bc 392
99512ac4
PA
393 checkkwd = CHKNL | CHKKWD | CHKALIAS;
394 is_subshell = 0;
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MD
395 redir = NULL;
396 n1 = NULL;
397 rpp = &redir;
398
399 /* Check for redirection which may precede command */
400 while (readtoken() == TREDIR) {
401 *rpp = n2 = redirnode;
402 rpp = &n2->nfile.next;
403 parsefname();
404 }
405 tokpushback++;
406
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407 switch (readtoken()) {
408 case TIF:
409 n1 = (union node *)stalloc(sizeof (struct nif));
410 n1->type = NIF;
99512ac4 411 if ((n1->nif.test = list(0, 0)) == NULL)
3c79a5ea 412 synexpect(-1);
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413 if (readtoken() != TTHEN)
414 synexpect(TTHEN);
99512ac4 415 n1->nif.ifpart = list(0, 0);
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416 n2 = n1;
417 while (readtoken() == TELIF) {
418 n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif));
419 n2 = n2->nif.elsepart;
420 n2->type = NIF;
99512ac4 421 if ((n2->nif.test = list(0, 0)) == NULL)
3c79a5ea 422 synexpect(-1);
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423 if (readtoken() != TTHEN)
424 synexpect(TTHEN);
99512ac4 425 n2->nif.ifpart = list(0, 0);
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426 }
427 if (lasttoken == TELSE)
99512ac4 428 n2->nif.elsepart = list(0, 0);
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429 else {
430 n2->nif.elsepart = NULL;
431 tokpushback++;
432 }
433 if (readtoken() != TFI)
434 synexpect(TFI);
99512ac4 435 checkkwd = CHKKWD | CHKALIAS;
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436 break;
437 case TWHILE:
438 case TUNTIL: {
439 int got;
440 n1 = (union node *)stalloc(sizeof (struct nbinary));
441 n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL;
99512ac4 442 if ((n1->nbinary.ch1 = list(0, 0)) == NULL)
3c79a5ea 443 synexpect(-1);
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MD
444 if ((got=readtoken()) != TDO) {
445TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : ""));
446 synexpect(TDO);
447 }
99512ac4 448 n1->nbinary.ch2 = list(0, 0);
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449 if (readtoken() != TDONE)
450 synexpect(TDONE);
99512ac4 451 checkkwd = CHKKWD | CHKALIAS;
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452 break;
453 }
454 case TFOR:
455 if (readtoken() != TWORD || quoteflag || ! goodname(wordtext))
456 synerror("Bad for loop variable");
457 n1 = (union node *)stalloc(sizeof (struct nfor));
458 n1->type = NFOR;
459 n1->nfor.var = wordtext;
99512ac4
PA
460 while (readtoken() == TNL)
461 ;
462 if (lasttoken == TWORD && ! quoteflag && equal(wordtext, "in")) {
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MD
463 app = &ap;
464 while (readtoken() == TWORD) {
465 n2 = (union node *)stalloc(sizeof (struct narg));
466 n2->type = NARG;
467 n2->narg.text = wordtext;
468 n2->narg.backquote = backquotelist;
469 *app = n2;
470 app = &n2->narg.next;
471 }
472 *app = NULL;
473 n1->nfor.args = ap;
474 if (lasttoken != TNL && lasttoken != TSEMI)
475 synexpect(-1);
476 } else {
3c79a5ea
PA
477 static char argvars[5] = {
478 CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0'
479 };
984263bc
MD
480 n2 = (union node *)stalloc(sizeof (struct narg));
481 n2->type = NARG;
934863d7 482 n2->narg.text = argvars;
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483 n2->narg.backquote = NULL;
484 n2->narg.next = NULL;
485 n1->nfor.args = n2;
486 /*
487 * Newline or semicolon here is optional (but note
488 * that the original Bourne shell only allowed NL).
489 */
490 if (lasttoken != TNL && lasttoken != TSEMI)
491 tokpushback++;
492 }
99512ac4 493 checkkwd = CHKNL | CHKKWD | CHKALIAS;
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494 if ((t = readtoken()) == TDO)
495 t = TDONE;
496 else if (t == TBEGIN)
497 t = TEND;
498 else
499 synexpect(-1);
99512ac4 500 n1->nfor.body = list(0, 0);
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501 if (readtoken() != t)
502 synexpect(t);
99512ac4 503 checkkwd = CHKKWD | CHKALIAS;
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504 break;
505 case TCASE:
506 n1 = (union node *)stalloc(sizeof (struct ncase));
507 n1->type = NCASE;
508 if (readtoken() != TWORD)
509 synexpect(TWORD);
510 n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg));
511 n2->type = NARG;
512 n2->narg.text = wordtext;
513 n2->narg.backquote = backquotelist;
514 n2->narg.next = NULL;
515 while (readtoken() == TNL);
516 if (lasttoken != TWORD || ! equal(wordtext, "in"))
517 synerror("expecting \"in\"");
518 cpp = &n1->ncase.cases;
99512ac4 519 checkkwd = CHKNL | CHKKWD, readtoken();
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MD
520 while (lasttoken != TESAC) {
521 *cpp = cp = (union node *)stalloc(sizeof (struct nclist));
522 cp->type = NCLIST;
523 app = &cp->nclist.pattern;
524 if (lasttoken == TLP)
525 readtoken();
526 for (;;) {
527 *app = ap = (union node *)stalloc(sizeof (struct narg));
528 ap->type = NARG;
529 ap->narg.text = wordtext;
530 ap->narg.backquote = backquotelist;
99512ac4
PA
531 checkkwd = CHKNL | CHKKWD;
532 if (readtoken() != TPIPE)
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MD
533 break;
534 app = &ap->narg.next;
535 readtoken();
536 }
537 ap->narg.next = NULL;
538 if (lasttoken != TRP)
99512ac4
PA
539 synexpect(TRP);
540 cp->nclist.body = list(0, 0);
984263bc 541
99512ac4 542 checkkwd = CHKNL | CHKKWD | CHKALIAS;
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MD
543 if ((t = readtoken()) != TESAC) {
544 if (t != TENDCASE)
99512ac4 545 synexpect(TENDCASE);
984263bc 546 else
99512ac4 547 checkkwd = CHKNL | CHKKWD, readtoken();
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MD
548 }
549 cpp = &cp->nclist.next;
550 }
984263bc 551 *cpp = NULL;
99512ac4 552 checkkwd = CHKKWD | CHKALIAS;
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MD
553 break;
554 case TLP:
555 n1 = (union node *)stalloc(sizeof (struct nredir));
556 n1->type = NSUBSHELL;
99512ac4 557 n1->nredir.n = list(0, 0);
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558 n1->nredir.redirect = NULL;
559 if (readtoken() != TRP)
560 synexpect(TRP);
99512ac4
PA
561 checkkwd = CHKKWD | CHKALIAS;
562 is_subshell = 1;
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563 break;
564 case TBEGIN:
99512ac4 565 n1 = list(0, 0);
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566 if (readtoken() != TEND)
567 synexpect(TEND);
99512ac4 568 checkkwd = CHKKWD | CHKALIAS;
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569 break;
570 /* Handle an empty command like other simple commands. */
99512ac4 571 case TBACKGND:
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572 case TSEMI:
573 case TAND:
574 case TOR:
575 /*
576 * An empty command before a ; doesn't make much sense, and
577 * should certainly be disallowed in the case of `if ;'.
578 */
579 if (!redir)
580 synexpect(-1);
581 case TNL:
582 case TEOF:
583 case TWORD:
584 case TRP:
585 tokpushback++;
99512ac4
PA
586 n1 = simplecmd(rpp, redir);
587 return n1;
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588 default:
589 synexpect(-1);
590 }
591
592 /* Now check for redirection which may follow command */
593 while (readtoken() == TREDIR) {
594 *rpp = n2 = redirnode;
595 rpp = &n2->nfile.next;
596 parsefname();
597 }
598 tokpushback++;
599 *rpp = NULL;
600 if (redir) {
99512ac4 601 if (!is_subshell) {
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MD
602 n2 = (union node *)stalloc(sizeof (struct nredir));
603 n2->type = NREDIR;
604 n2->nredir.n = n1;
605 n1 = n2;
606 }
607 n1->nredir.redirect = redir;
608 }
99512ac4 609
5c454bc1 610 return n1;
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611}
612
613
99512ac4 614static union node *
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615simplecmd(union node **rpp, union node *redir)
616{
617 union node *args, **app;
618 union node **orig_rpp = rpp;
5c454bc1 619 union node *n = NULL;
99512ac4 620 int special;
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MD
621
622 /* If we don't have any redirections already, then we must reset */
623 /* rpp to be the address of the local redir variable. */
624 if (redir == 0)
625 rpp = &redir;
626
627 args = NULL;
628 app = &args;
629 /*
630 * We save the incoming value, because we need this for shell
631 * functions. There can not be a redirect or an argument between
632 * the function name and the open parenthesis.
633 */
634 orig_rpp = rpp;
635
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636 for (;;) {
637 if (readtoken() == TWORD) {
638 n = (union node *)stalloc(sizeof (struct narg));
639 n->type = NARG;
640 n->narg.text = wordtext;
641 n->narg.backquote = backquotelist;
642 *app = n;
643 app = &n->narg.next;
644 } else if (lasttoken == TREDIR) {
645 *rpp = n = redirnode;
646 rpp = &n->nfile.next;
647 parsefname(); /* read name of redirection file */
648 } else if (lasttoken == TLP && app == &args->narg.next
649 && rpp == orig_rpp) {
650 /* We have a function */
651 if (readtoken() != TRP)
652 synexpect(TRP);
e0752c76 653 funclinno = plinno;
99512ac4
PA
654 /*
655 * - Require plain text.
656 * - Functions with '/' cannot be called.
657 * - Reject name=().
658 * - Reject ksh extended glob patterns.
659 */
660 if (!noexpand(n->narg.text) || quoteflag ||
661 strchr(n->narg.text, '/') ||
662 strchr("!%*+-=?@}~",
663 n->narg.text[strlen(n->narg.text) - 1]))
984263bc 664 synerror("Bad function name");
99512ac4
PA
665 rmescapes(n->narg.text);
666 if (find_builtin(n->narg.text, &special) >= 0 &&
667 special)
668 synerror("Cannot override a special builtin with a function");
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MD
669 n->type = NDEFUN;
670 n->narg.next = command();
e0752c76 671 funclinno = 0;
5c454bc1 672 return n;
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MD
673 } else {
674 tokpushback++;
675 break;
676 }
677 }
678 *app = NULL;
679 *rpp = NULL;
680 n = (union node *)stalloc(sizeof (struct ncmd));
681 n->type = NCMD;
682 n->ncmd.backgnd = 0;
683 n->ncmd.args = args;
684 n->ncmd.redirect = redir;
5c454bc1 685 return n;
984263bc
MD
686}
687
99512ac4 688static union node *
984263bc
MD
689makename(void)
690{
691 union node *n;
692
693 n = (union node *)stalloc(sizeof (struct narg));
694 n->type = NARG;
695 n->narg.next = NULL;
696 n->narg.text = wordtext;
697 n->narg.backquote = backquotelist;
698 return n;
699}
700
1f0f7b35
SW
701void
702fixredir(union node *n, const char *text, int err)
984263bc
MD
703{
704 TRACE(("Fix redir %s %d\n", text, err));
705 if (!err)
706 n->ndup.vname = NULL;
707
708 if (is_digit(text[0]) && text[1] == '\0')
709 n->ndup.dupfd = digit_val(text[0]);
710 else if (text[0] == '-' && text[1] == '\0')
711 n->ndup.dupfd = -1;
712 else {
713
714 if (err)
715 synerror("Bad fd number");
716 else
717 n->ndup.vname = makename();
718 }
719}
720
721
99512ac4 722static void
984263bc
MD
723parsefname(void)
724{
725 union node *n = redirnode;
726
727 if (readtoken() != TWORD)
728 synexpect(-1);
729 if (n->type == NHERE) {
730 struct heredoc *here = heredoc;
731 struct heredoc *p;
732 int i;
733
734 if (quoteflag == 0)
735 n->type = NXHERE;
736 TRACE(("Here document %d\n", n->type));
737 if (here->striptabs) {
738 while (*wordtext == '\t')
739 wordtext++;
740 }
741 if (! noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN)
742 synerror("Illegal eof marker for << redirection");
743 rmescapes(wordtext);
744 here->eofmark = wordtext;
745 here->next = NULL;
746 if (heredoclist == NULL)
747 heredoclist = here;
748 else {
749 for (p = heredoclist ; p->next ; p = p->next);
750 p->next = here;
751 }
752 } else if (n->type == NTOFD || n->type == NFROMFD) {
753 fixredir(n, wordtext, 0);
754 } else {
755 n->nfile.fname = makename();
756 }
757}
758
759
760/*
761 * Input any here documents.
762 */
763
99512ac4 764static void
984263bc
MD
765parseheredoc(void)
766{
767 struct heredoc *here;
768 union node *n;
769
770 while (heredoclist) {
771 here = heredoclist;
772 heredoclist = here->next;
773 if (needprompt) {
774 setprompt(2);
775 needprompt = 0;
776 }
777 readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX,
778 here->eofmark, here->striptabs);
779 n = (union node *)stalloc(sizeof (struct narg));
780 n->narg.type = NARG;
781 n->narg.next = NULL;
782 n->narg.text = wordtext;
783 n->narg.backquote = backquotelist;
784 here->here->nhere.doc = n;
785 }
786}
787
99512ac4 788static int
984263bc
MD
789peektoken(void)
790{
791 int t;
792
793 t = readtoken();
794 tokpushback++;
795 return (t);
796}
797
99512ac4 798static int
984263bc
MD
799readtoken(void)
800{
801 int t;
984263bc
MD
802 struct alias *ap;
803#ifdef DEBUG
804 int alreadyseen = tokpushback;
805#endif
806
807 top:
808 t = xxreadtoken();
809
99512ac4
PA
810 /*
811 * eat newlines
812 */
813 if (checkkwd & CHKNL) {
814 while (t == TNL) {
815 parseheredoc();
816 t = xxreadtoken();
817 }
818 }
984263bc 819
99512ac4
PA
820 /*
821 * check for keywords and aliases
822 */
823 if (t == TWORD && !quoteflag)
824 {
825 const char * const *pp;
826
827 if (checkkwd & CHKKWD)
984263bc
MD
828 for (pp = parsekwd; *pp; pp++) {
829 if (**pp == *wordtext && equal(*pp, wordtext))
830 {
831 lasttoken = t = pp - parsekwd + KWDOFFSET;
832 TRACE(("keyword %s recognized\n", tokname[t]));
833 goto out;
834 }
835 }
99512ac4
PA
836 if (checkkwd & CHKALIAS &&
837 (ap = lookupalias(wordtext, 1)) != NULL) {
838 pushstring(ap->val, strlen(ap->val), ap);
839 goto top;
984263bc 840 }
99512ac4 841 }
984263bc 842out:
99512ac4 843 if (t != TNOT)
5c454bc1 844 checkkwd = 0;
99512ac4 845
984263bc
MD
846#ifdef DEBUG
847 if (!alreadyseen)
848 TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
849 else
850 TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
851#endif
852 return (t);
853}
854
855
856/*
857 * Read the next input token.
858 * If the token is a word, we set backquotelist to the list of cmds in
859 * backquotes. We set quoteflag to true if any part of the word was
860 * quoted.
861 * If the token is TREDIR, then we set redirnode to a structure containing
862 * the redirection.
863 * In all cases, the variable startlinno is set to the number of the line
864 * on which the token starts.
865 *
866 * [Change comment: here documents and internal procedures]
867 * [Readtoken shouldn't have any arguments. Perhaps we should make the
868 * word parsing code into a separate routine. In this case, readtoken
869 * doesn't need to have any internal procedures, but parseword does.
870 * We could also make parseoperator in essence the main routine, and
871 * have parseword (readtoken1?) handle both words and redirection.]
872 */
873
874#define RETURN(token) return lasttoken = token
875
99512ac4 876static int
984263bc
MD
877xxreadtoken(void)
878{
879 int c;
880
881 if (tokpushback) {
882 tokpushback = 0;
883 return lasttoken;
884 }
885 if (needprompt) {
886 setprompt(2);
887 needprompt = 0;
888 }
889 startlinno = plinno;
890 for (;;) { /* until token or start of word found */
891 c = pgetc_macro();
984263bc
MD
892 switch (c) {
893 case ' ': case '\t':
894 continue;
895 case '#':
896 while ((c = pgetc()) != '\n' && c != PEOF);
897 pungetc();
898 continue;
899 case '\\':
900 if (pgetc() == '\n') {
901 startlinno = ++plinno;
902 if (doprompt)
903 setprompt(2);
904 else
905 setprompt(0);
906 continue;
907 }
908 pungetc();
909 goto breakloop;
910 case '\n':
911 plinno++;
912 needprompt = doprompt;
913 RETURN(TNL);
914 case PEOF:
915 RETURN(TEOF);
916 case '&':
917 if (pgetc() == '&')
918 RETURN(TAND);
919 pungetc();
920 RETURN(TBACKGND);
921 case '|':
922 if (pgetc() == '|')
923 RETURN(TOR);
924 pungetc();
925 RETURN(TPIPE);
926 case ';':
927 if (pgetc() == ';')
928 RETURN(TENDCASE);
929 pungetc();
930 RETURN(TSEMI);
931 case '(':
932 RETURN(TLP);
933 case ')':
934 RETURN(TRP);
935 default:
936 goto breakloop;
937 }
938 }
939breakloop:
2038fb68 940 return readtoken1(c, BASESYNTAX, NULL, 0);
984263bc
MD
941#undef RETURN
942}
943
944
99512ac4
PA
945#define MAXNEST_STATIC 8
946struct tokenstate
947{
948 const char *syntax; /* *SYNTAX */
949 int parenlevel; /* levels of parentheses in arithmetic */
950 enum tokenstate_category
951 {
952 TSTATE_TOP,
953 TSTATE_VAR_OLD, /* ${var+-=?}, inherits dquotes */
954 TSTATE_VAR_NEW, /* other ${var...}, own dquote state */
955 TSTATE_ARITH
956 } category;
957};
958
959
960/*
961 * Called to parse command substitutions.
962 */
963
964static char *
965parsebackq(char *out, struct nodelist **pbqlist,
966 int oldstyle, int dblquote, int quoted)
967{
968 struct nodelist **nlpp;
969 union node *n;
970 char *volatile str;
971 struct jmploc jmploc;
972 struct jmploc *const savehandler = handler;
973 int savelen;
974 int saveprompt;
975 const int bq_startlinno = plinno;
976 char *volatile ostr = NULL;
977 struct parsefile *const savetopfile = getcurrentfile();
978 struct heredoc *const saveheredoclist = heredoclist;
979 struct heredoc *here;
980
981 str = NULL;
982 if (setjmp(jmploc.loc)) {
983 popfilesupto(savetopfile);
984 if (str)
985 ckfree(str);
986 if (ostr)
987 ckfree(ostr);
988 heredoclist = saveheredoclist;
989 handler = savehandler;
990 if (exception == EXERROR) {
991 startlinno = bq_startlinno;
992 synerror("Error in command substitution");
993 }
994 longjmp(handler->loc, 1);
995 }
996 INTOFF;
997 savelen = out - stackblock();
998 if (savelen > 0) {
999 str = ckmalloc(savelen);
1000 memcpy(str, stackblock(), savelen);
1001 }
1002 handler = &jmploc;
1003 heredoclist = NULL;
1004 INTON;
1005 if (oldstyle) {
1006 /*
1007 * We must read until the closing backquote, giving special
1008 * treatment to some slashes, and then push the string and
1009 * reread it as input, interpreting it normally.
1010 */
1011 char *oout;
1012 int c, olen;
1013
1014 STARTSTACKSTR(oout);
1015 for (;;) {
1016 if (needprompt) {
1017 setprompt(2);
1018 needprompt = 0;
1019 }
1020 CHECKSTRSPACE(2, oout);
1021 switch (c = pgetc()) {
1022 case '`':
1023 goto done;
1024
1025 case '\\':
1026 if ((c = pgetc()) == '\n') {
1027 plinno++;
1028 if (doprompt)
1029 setprompt(2);
1030 else
1031 setprompt(0);
1032 /*
1033 * If eating a newline, avoid putting
1034 * the newline into the new character
1035 * stream (via the USTPUTC after the
1036 * switch).
1037 */
1038 continue;
1039 }
1040 if (c != '\\' && c != '`' && c != '$'
1041 && (!dblquote || c != '"'))
1042 USTPUTC('\\', oout);
1043 break;
1044
1045 case '\n':
1046 plinno++;
1047 needprompt = doprompt;
1048 break;
1049
1050 case PEOF:
1051 startlinno = plinno;
1052 synerror("EOF in backquote substitution");
1053 break;
1054
1055 default:
1056 break;
1057 }
1058 USTPUTC(c, oout);
1059 }
1060done:
1061 USTPUTC('\0', oout);
1062 olen = oout - stackblock();
1063 INTOFF;
1064 ostr = ckmalloc(olen);
1065 memcpy(ostr, stackblock(), olen);
1066 setinputstring(ostr, 1);
1067 INTON;
1068 }
1069 nlpp = pbqlist;
1070 while (*nlpp)
1071 nlpp = &(*nlpp)->next;
1072 *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist));
1073 (*nlpp)->next = NULL;
1074
1075 if (oldstyle) {
1076 saveprompt = doprompt;
1077 doprompt = 0;
1078 }
1079
1080 n = list(0, oldstyle);
1081
1082 if (oldstyle)
1083 doprompt = saveprompt;
1084 else {
1085 if (readtoken() != TRP)
1086 synexpect(TRP);
1087 }
1088
1089 (*nlpp)->n = n;
1090 if (oldstyle) {
1091 /*
1092 * Start reading from old file again, ignoring any pushed back
1093 * tokens left from the backquote parsing
1094 */
1095 popfile();
1096 tokpushback = 0;
1097 }
1098 STARTSTACKSTR(out);
1099 CHECKSTRSPACE(savelen + 1, out);
1100 INTOFF;
1101 if (str) {
1102 memcpy(out, str, savelen);
1103 STADJUST(savelen, out);
1104 ckfree(str);
1105 str = NULL;
1106 }
1107 if (ostr) {
1108 ckfree(ostr);
1109 ostr = NULL;
1110 }
1111 here = saveheredoclist;
1112 if (here != NULL) {
1113 while (here->next != NULL)
1114 here = here->next;
1115 here->next = heredoclist;
1116 heredoclist = saveheredoclist;
1117 }
1118 handler = savehandler;
1119 INTON;
1120 if (quoted)
1121 USTPUTC(CTLBACKQ | CTLQUOTE, out);
1122 else
1123 USTPUTC(CTLBACKQ, out);
1124 return out;
1125}
1126
984263bc
MD
1127
1128/*
e1489450
PA
1129 * Called to parse a backslash escape sequence inside $'...'.
1130 * The backslash has already been read.
1131 */
1132static char *
1133readcstyleesc(char *out)
1134{
1135 int c, v, i, n;
1136
1137 c = pgetc();
1138 switch (c) {
1139 case '\0':
1140 synerror("Unterminated quoted string");
1141 case '\n':
1142 plinno++;
1143 if (doprompt)
1144 setprompt(2);
1145 else
1146 setprompt(0);
1147 return out;
1148 case '\\':
1149 case '\'':
1150 case '"':
1151 v = c;
1152 break;
1153 case 'a': v = '\a'; break;
1154 case 'b': v = '\b'; break;
1155 case 'e': v = '\033'; break;
1156 case 'f': v = '\f'; break;
1157 case 'n': v = '\n'; break;
1158 case 'r': v = '\r'; break;
1159 case 't': v = '\t'; break;
1160 case 'v': v = '\v'; break;
1161 case 'x':
1162 v = 0;
1163 for (;;) {
1164 c = pgetc();
1165 if (c >= '0' && c <= '9')
1166 v = (v << 4) + c - '0';
1167 else if (c >= 'A' && c <= 'F')
1168 v = (v << 4) + c - 'A' + 10;
1169 else if (c >= 'a' && c <= 'f')
1170 v = (v << 4) + c - 'a' + 10;
1171 else
1172 break;
1173 }
1174 pungetc();
1175 break;
1176 case '0': case '1': case '2': case '3':
1177 case '4': case '5': case '6': case '7':
1178 v = c - '0';
1179 c = pgetc();
1180 if (c >= '0' && c <= '7') {
1181 v <<= 3;
1182 v += c - '0';
1183 c = pgetc();
1184 if (c >= '0' && c <= '7') {
1185 v <<= 3;
1186 v += c - '0';
1187 } else
1188 pungetc();
1189 } else
1190 pungetc();
1191 break;
1192 case 'c':
1193 c = pgetc();
1194 if (c < 0x3f || c > 0x7a || c == 0x60)
1195 synerror("Bad escape sequence");
1196 if (c == '\\' && pgetc() != '\\')
1197 synerror("Bad escape sequence");
1198 if (c == '?')
1199 v = 127;
1200 else
1201 v = c & 0x1f;
1202 break;
1203 case 'u':
1204 case 'U':
1205 n = c == 'U' ? 8 : 4;
1206 v = 0;
1207 for (i = 0; i < n; i++) {
1208 c = pgetc();
1209 if (c >= '0' && c <= '9')
1210 v = (v << 4) + c - '0';
1211 else if (c >= 'A' && c <= 'F')
1212 v = (v << 4) + c - 'A' + 10;
1213 else if (c >= 'a' && c <= 'f')
1214 v = (v << 4) + c - 'a' + 10;
1215 else
1216 synerror("Bad escape sequence");
1217 }
1218 if (v == 0 || (v >= 0xd800 && v <= 0xdfff))
1219 synerror("Bad escape sequence");
1220 /* We really need iconv here. */
1221 if (v > 127)
1222 v = '?';
1223 break;
1224 default:
1225 synerror("Bad escape sequence");
1226 }
1227 v = (char)v;
1228 /*
1229 * We can't handle NUL bytes.
1230 * POSIX says we should skip till the closing quote.
1231 */
1232 if (v == '\0') {
1233 while ((c = pgetc()) != '\'') {
1234 if (c == '\\')
1235 c = pgetc();
1236 if (c == PEOF)
1237 synerror("Unterminated quoted string");
1238 }
1239 pungetc();
1240 return out;
1241 }
1242 if (SQSYNTAX[v] == CCTL)
1243 USTPUTC(CTLESC, out);
1244 USTPUTC(v, out);
1245 return out;
1246}
1247
1248
1249/*
984263bc
MD
1250 * If eofmark is NULL, read a word or a redirection symbol. If eofmark
1251 * is not NULL, read a here document. In the latter case, eofmark is the
1252 * word which marks the end of the document and striptabs is true if
1253 * leading tabs should be stripped from the document. The argument firstc
1254 * is the first character of the input token or document.
1255 *
1256 * Because C does not have internal subroutines, I have simulated them
1257 * using goto's to implement the subroutine linkage. The following macros
1258 * will run code that appears at the end of readtoken1.
1259 */
1260
1261#define CHECKEND() {goto checkend; checkend_return:;}
1262#define PARSEREDIR() {goto parseredir; parseredir_return:;}
1263#define PARSESUB() {goto parsesub; parsesub_return:;}
984263bc
MD
1264#define PARSEARITH() {goto parsearith; parsearith_return:;}
1265
99512ac4
PA
1266static int
1267readtoken1(int firstc, char const *initialsyntax, char *eofmark, int striptabs)
984263bc
MD
1268{
1269 int c = firstc;
f2aa3fa5 1270 char * volatile out;
984263bc
MD
1271 int len;
1272 char line[EOFMARKLEN + 1];
1273 struct nodelist *bqlist;
f2aa3fa5 1274 volatile int quotef;
99512ac4
PA
1275 int newvarnest;
1276 int level;
984263bc 1277 int synentry;
99512ac4
PA
1278 struct tokenstate state_static[MAXNEST_STATIC];
1279 int maxnest = MAXNEST_STATIC;
1280 struct tokenstate *state = state_static;
e1489450 1281 int sqiscstyle = 0;
984263bc
MD
1282
1283 startlinno = plinno;
984263bc
MD
1284 quotef = 0;
1285 bqlist = NULL;
99512ac4
PA
1286 newvarnest = 0;
1287 level = 0;
1288 state[level].syntax = initialsyntax;
1289 state[level].parenlevel = 0;
1290 state[level].category = TSTATE_TOP;
984263bc
MD
1291
1292 STARTSTACKSTR(out);
1293 loop: { /* for each line, until end of word */
984263bc
MD
1294 CHECKEND(); /* set c to PEOF if at end of here document */
1295 for (;;) { /* until end of line or end of word */
99512ac4 1296 CHECKSTRSPACE(4, out); /* permit 4 calls to USTPUTC */
984263bc 1297
99512ac4 1298 synentry = state[level].syntax[c];
984263bc
MD
1299
1300 switch(synentry) {
1301 case CNL: /* '\n' */
99512ac4 1302 if (state[level].syntax == BASESYNTAX)
984263bc
MD
1303 goto endword; /* exit outer loop */
1304 USTPUTC(c, out);
1305 plinno++;
1306 if (doprompt)
1307 setprompt(2);
1308 else
1309 setprompt(0);
1310 c = pgetc();
1311 goto loop; /* continue outer loop */
e1489450
PA
1312 case CSBACK:
1313 if (sqiscstyle) {
1314 out = readcstyleesc(out);
1315 break;
1316 }
1317 /* FALLTHROUGH */
984263bc
MD
1318 case CWORD:
1319 USTPUTC(c, out);
1320 break;
1321 case CCTL:
99512ac4 1322 if (eofmark == NULL || initialsyntax != SQSYNTAX)
984263bc
MD
1323 USTPUTC(CTLESC, out);
1324 USTPUTC(c, out);
1325 break;
1326 case CBACK: /* backslash */
1327 c = pgetc();
1328 if (c == PEOF) {
1329 USTPUTC('\\', out);
1330 pungetc();
1331 } else if (c == '\n') {
3c79a5ea 1332 plinno++;
984263bc
MD
1333 if (doprompt)
1334 setprompt(2);
1335 else
1336 setprompt(0);
1337 } else {
99512ac4
PA
1338 if (state[level].syntax == DQSYNTAX &&
1339 c != '\\' && c != '`' && c != '$' &&
1340 (c != '"' || (eofmark != NULL &&
1341 newvarnest == 0)) &&
1342 (c != '}' || state[level].category != TSTATE_VAR_OLD))
984263bc 1343 USTPUTC('\\', out);
99512ac4
PA
1344 if ((eofmark == NULL ||
1345 newvarnest > 0) &&
1346 state[level].syntax == BASESYNTAX)
1347 USTPUTC(CTLQUOTEMARK, out);
984263bc
MD
1348 if (SQSYNTAX[c] == CCTL)
1349 USTPUTC(CTLESC, out);
984263bc 1350 USTPUTC(c, out);
99512ac4
PA
1351 if ((eofmark == NULL ||
1352 newvarnest > 0) &&
1353 state[level].syntax == BASESYNTAX &&
1354 state[level].category == TSTATE_VAR_OLD)
1355 USTPUTC(CTLQUOTEEND, out);
984263bc
MD
1356 quotef++;
1357 }
1358 break;
1359 case CSQUOTE:
99512ac4
PA
1360 USTPUTC(CTLQUOTEMARK, out);
1361 state[level].syntax = SQSYNTAX;
e1489450 1362 sqiscstyle = 0;
984263bc
MD
1363 break;
1364 case CDQUOTE:
99512ac4
PA
1365 USTPUTC(CTLQUOTEMARK, out);
1366 state[level].syntax = DQSYNTAX;
984263bc
MD
1367 break;
1368 case CENDQUOTE:
99512ac4 1369 if (eofmark != NULL && newvarnest == 0)
984263bc 1370 USTPUTC(c, out);
99512ac4
PA
1371 else {
1372 if (state[level].category == TSTATE_VAR_OLD)
1373 USTPUTC(CTLQUOTEEND, out);
1374 state[level].syntax = BASESYNTAX;
984263bc
MD
1375 quotef++;
1376 }
1377 break;
1378 case CVAR: /* '$' */
1379 PARSESUB(); /* parse substitution */
1380 break;
1381 case CENDVAR: /* '}' */
99512ac4
PA
1382 if (level > 0 &&
1383 ((state[level].category == TSTATE_VAR_OLD &&
1384 state[level].syntax ==
1385 state[level - 1].syntax) ||
1386 (state[level].category == TSTATE_VAR_NEW &&
1387 state[level].syntax == BASESYNTAX))) {
1388 if (state[level].category == TSTATE_VAR_NEW)
1389 newvarnest--;
1390 level--;
984263bc
MD
1391 USTPUTC(CTLENDVAR, out);
1392 } else {
1393 USTPUTC(c, out);
1394 }
1395 break;
1396 case CLP: /* '(' in arithmetic */
99512ac4 1397 state[level].parenlevel++;
984263bc
MD
1398 USTPUTC(c, out);
1399 break;
1400 case CRP: /* ')' in arithmetic */
99512ac4 1401 if (state[level].parenlevel > 0) {
984263bc 1402 USTPUTC(c, out);
99512ac4 1403 --state[level].parenlevel;
984263bc
MD
1404 } else {
1405 if (pgetc() == ')') {
99512ac4
PA
1406 if (level > 0 &&
1407 state[level].category == TSTATE_ARITH) {
1408 level--;
984263bc 1409 USTPUTC(CTLENDARI, out);
984263bc
MD
1410 } else
1411 USTPUTC(')', out);
1412 } else {
1413 /*
1414 * unbalanced parens
1415 * (don't 2nd guess - no error)
1416 */
1417 pungetc();
1418 USTPUTC(')', out);
1419 }
1420 }
1421 break;
1422 case CBQUOTE: /* '`' */
99512ac4
PA
1423 out = parsebackq(out, &bqlist, 1,
1424 state[level].syntax == DQSYNTAX &&
1425 (eofmark == NULL || newvarnest > 0),
1426 state[level].syntax == DQSYNTAX || state[level].syntax == ARISYNTAX);
984263bc
MD
1427 break;
1428 case CEOF:
1429 goto endword; /* exit outer loop */
99512ac4
PA
1430 case CIGN:
1431 break;
984263bc 1432 default:
99512ac4 1433 if (level == 0)
984263bc
MD
1434 goto endword; /* exit outer loop */
1435 USTPUTC(c, out);
1436 }
1437 c = pgetc_macro();
1438 }
1439 }
1440endword:
99512ac4 1441 if (state[level].syntax == ARISYNTAX)
984263bc 1442 synerror("Missing '))'");
99512ac4 1443 if (state[level].syntax != BASESYNTAX && eofmark == NULL)
984263bc 1444 synerror("Unterminated quoted string");
99512ac4
PA
1445 if (state[level].category == TSTATE_VAR_OLD ||
1446 state[level].category == TSTATE_VAR_NEW) {
984263bc
MD
1447 startlinno = plinno;
1448 synerror("Missing '}'");
1449 }
99512ac4
PA
1450 if (state != state_static)
1451 parser_temp_free_upto(state);
984263bc
MD
1452 USTPUTC('\0', out);
1453 len = out - stackblock();
1454 out = stackblock();
1455 if (eofmark == NULL) {
1456 if ((c == '>' || c == '<')
1457 && quotef == 0
1458 && len <= 2
1459 && (*out == '\0' || is_digit(*out))) {
1460 PARSEREDIR();
1461 return lasttoken = TREDIR;
1462 } else {
1463 pungetc();
1464 }
1465 }
1466 quoteflag = quotef;
1467 backquotelist = bqlist;
1468 grabstackblock(len);
1469 wordtext = out;
1470 return lasttoken = TWORD;
1471/* end of readtoken routine */
1472
1473
984263bc
MD
1474/*
1475 * Check to see whether we are at the end of the here document. When this
1476 * is called, c is set to the first character of the next input line. If
1477 * we are at the end of the here document, this routine sets the c to PEOF.
1478 */
1479
1480checkend: {
1481 if (eofmark) {
1482 if (striptabs) {
1483 while (c == '\t')
1484 c = pgetc();
1485 }
1486 if (c == *eofmark) {
1487 if (pfgets(line, sizeof line) != NULL) {
1488 char *p, *q;
1489
1490 p = line;
1491 for (q = eofmark + 1 ; *q && *p == *q ; p++, q++);
1492 if (*p == '\n' && *q == '\0') {
1493 c = PEOF;
1494 plinno++;
1495 needprompt = doprompt;
1496 } else {
1497 pushstring(line, strlen(line), NULL);
1498 }
1499 }
1500 }
1501 }
1502 goto checkend_return;
1503}
1504
1505
1506/*
1507 * Parse a redirection operator. The variable "out" points to a string
1508 * specifying the fd to be redirected. The variable "c" contains the
1509 * first character of the redirection operator.
1510 */
1511
1512parseredir: {
1513 char fd = *out;
1514 union node *np;
1515
1516 np = (union node *)stalloc(sizeof (struct nfile));
1517 if (c == '>') {
1518 np->nfile.fd = 1;
1519 c = pgetc();
1520 if (c == '>')
1521 np->type = NAPPEND;
1522 else if (c == '&')
1523 np->type = NTOFD;
1524 else if (c == '|')
1525 np->type = NCLOBBER;
1526 else {
1527 np->type = NTO;
1528 pungetc();
1529 }
1530 } else { /* c == '<' */
1531 np->nfile.fd = 0;
1532 c = pgetc();
1533 if (c == '<') {
1534 if (sizeof (struct nfile) != sizeof (struct nhere)) {
1535 np = (union node *)stalloc(sizeof (struct nhere));
1536 np->nfile.fd = 0;
1537 }
1538 np->type = NHERE;
1539 heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc));
1540 heredoc->here = np;
1541 if ((c = pgetc()) == '-') {
1542 heredoc->striptabs = 1;
1543 } else {
1544 heredoc->striptabs = 0;
1545 pungetc();
1546 }
1547 } else if (c == '&')
1548 np->type = NFROMFD;
1549 else if (c == '>')
1550 np->type = NFROMTO;
1551 else {
1552 np->type = NFROM;
1553 pungetc();
1554 }
1555 }
1556 if (fd != '\0')
1557 np->nfile.fd = digit_val(fd);
1558 redirnode = np;
1559 goto parseredir_return;
1560}
1561
1562
1563/*
1564 * Parse a substitution. At this point, we have read the dollar sign
1565 * and nothing else.
1566 */
1567
1568parsesub: {
e0752c76 1569 char buf[10];
984263bc
MD
1570 int subtype;
1571 int typeloc;
1572 int flags;
1573 char *p;
984263bc 1574 static const char types[] = "}-+?=";
e0752c76 1575 int bracketed_name = 0; /* used to handle ${[0-9]*} variables */
e0752c76
SK
1576 int linno;
1577 int length;
6ea1c533 1578 int c1;
984263bc
MD
1579
1580 c = pgetc();
e1489450 1581 if (c == '(') { /* $(command) or $((arith)) */
984263bc
MD
1582 if (pgetc() == '(') {
1583 PARSEARITH();
1584 } else {
1585 pungetc();
99512ac4
PA
1586 out = parsebackq(out, &bqlist, 0,
1587 state[level].syntax == DQSYNTAX &&
1588 (eofmark == NULL || newvarnest > 0),
1589 state[level].syntax == DQSYNTAX ||
1590 state[level].syntax == ARISYNTAX);
984263bc 1591 }
e1489450 1592 } else if (c == '{' || is_name(c) || is_special(c)) {
984263bc
MD
1593 USTPUTC(CTLVAR, out);
1594 typeloc = out - stackblock();
1595 USTPUTC(VSNORMAL, out);
1596 subtype = VSNORMAL;
e0752c76 1597 flags = 0;
984263bc
MD
1598 if (c == '{') {
1599 bracketed_name = 1;
1600 c = pgetc();
6ea1c533 1601 subtype = 0;
984263bc 1602 }
6ea1c533 1603varname:
a3143cf4 1604 if (!is_eof(c) && is_name(c)) {
e0752c76 1605 length = 0;
984263bc
MD
1606 do {
1607 STPUTC(c, out);
1608 c = pgetc();
e0752c76 1609 length++;
a3143cf4 1610 } while (!is_eof(c) && is_in_name(c));
e0752c76
SK
1611 if (length == 6 &&
1612 strncmp(out - length, "LINENO", length) == 0) {
1613 /* Replace the variable name with the
1614 * current line number. */
1615 linno = plinno;
1616 if (funclinno != 0)
1617 linno -= funclinno - 1;
1618 snprintf(buf, sizeof(buf), "%d", linno);
1619 STADJUST(-6, out);
99512ac4 1620 STPUTS(buf, out);
e0752c76
SK
1621 flags |= VSLINENO;
1622 }
984263bc
MD
1623 } else if (is_digit(c)) {
1624 if (bracketed_name) {
1625 do {
1626 STPUTC(c, out);
1627 c = pgetc();
1628 } while (is_digit(c));
1629 } else {
1630 STPUTC(c, out);
1631 c = pgetc();
1632 }
6ea1c533
PA
1633 } else if (is_special(c)) {
1634 c1 = c;
1635 c = pgetc();
1636 if (subtype == 0 && c1 == '#') {
1637 subtype = VSLENGTH;
1638 if (strchr(types, c) == NULL && c != ':' &&
1639 c != '#' && c != '%')
1640 goto varname;
1641 c1 = c;
af260b21 1642 c = pgetc();
6ea1c533
PA
1643 if (c1 != '}' && c == '}') {
1644 pungetc();
1645 c = c1;
1646 goto varname;
1647 }
1648 pungetc();
1649 c = c1;
1650 c1 = '#';
1651 subtype = 0;
af260b21 1652 }
6ea1c533
PA
1653 USTPUTC(c1, out);
1654 } else {
1655 subtype = VSERROR;
1656 if (c == '}')
1657 pungetc();
1658 else if (c == '\n' || c == PEOF)
1659 synerror("Unexpected end of line in substitution");
1660 else
1661 USTPUTC(c, out);
984263bc 1662 }
984263bc
MD
1663 if (subtype == 0) {
1664 switch (c) {
1665 case ':':
e0752c76 1666 flags |= VSNUL;
984263bc
MD
1667 c = pgetc();
1668 /*FALLTHROUGH*/
1669 default:
1670 p = strchr(types, c);
af260b21 1671 if (p == NULL) {
99512ac4
PA
1672 if (c == '\n' || c == PEOF)
1673 synerror("Unexpected end of line in substitution");
af260b21
PA
1674 if (flags == VSNUL)
1675 STPUTC(':', out);
1676 STPUTC(c, out);
1677 subtype = VSERROR;
1678 } else
1679 subtype = p - types + VSNORMAL;
984263bc
MD
1680 break;
1681 case '%':
1682 case '#':
1683 {
1684 int cc = c;
1685 subtype = c == '#' ? VSTRIMLEFT :
1686 VSTRIMRIGHT;
1687 c = pgetc();
1688 if (c == cc)
1689 subtype++;
1690 else
1691 pungetc();
1692 break;
1693 }
1694 }
af260b21 1695 } else if (subtype != VSERROR) {
f41d807a
PA
1696 if (subtype == VSLENGTH && c != '}')
1697 subtype = VSERROR;
984263bc
MD
1698 pungetc();
1699 }
af260b21 1700 STPUTC('=', out);
b6942187
PA
1701 if (state[level].syntax == DQSYNTAX ||
1702 state[level].syntax == ARISYNTAX)
984263bc
MD
1703 flags |= VSQUOTE;
1704 *(stackblock() + typeloc) = subtype | flags;
99512ac4
PA
1705 if (subtype != VSNORMAL) {
1706 if (level + 1 >= maxnest) {
1707 maxnest *= 2;
1708 if (state == state_static) {
1709 state = parser_temp_alloc(
1710 maxnest * sizeof(*state));
1711 memcpy(state, state_static,
1712 MAXNEST_STATIC * sizeof(*state));
1713 } else
1714 state = parser_temp_realloc(state,
1715 maxnest * sizeof(*state));
984263bc 1716 }
99512ac4
PA
1717 level++;
1718 state[level].parenlevel = 0;
1719 if (subtype == VSMINUS || subtype == VSPLUS ||
1720 subtype == VSQUESTION || subtype == VSASSIGN) {
1721 /*
1722 * For operators that were in the Bourne shell,
1723 * inherit the double-quote state.
1724 */
1725 state[level].syntax = state[level - 1].syntax;
1726 state[level].category = TSTATE_VAR_OLD;
1727 } else {
1728 /*
1729 * The other operators take a pattern,
1730 * so go to BASESYNTAX.
1731 * Also, ' and " are now special, even
1732 * in here documents.
1733 */
1734 state[level].syntax = BASESYNTAX;
1735 state[level].category = TSTATE_VAR_NEW;
1736 newvarnest++;
984263bc 1737 }
99512ac4 1738 }
e1489450
PA
1739 } else if (c == '\'' && state[level].syntax == BASESYNTAX) {
1740 /* $'cstylequotes' */
1741 USTPUTC(CTLQUOTEMARK, out);
1742 state[level].syntax = SQSYNTAX;
1743 sqiscstyle = 1;
1744 } else {
1745 USTPUTC('$', out);
1746 pungetc();
984263bc 1747 }
99512ac4 1748 goto parsesub_return;
984263bc
MD
1749}
1750
99512ac4 1751
984263bc
MD
1752/*
1753 * Parse an arithmetic expansion (indicate start of one and set state)
1754 */
1755parsearith: {
1756
99512ac4
PA
1757 if (level + 1 >= maxnest) {
1758 maxnest *= 2;
1759 if (state == state_static) {
1760 state = parser_temp_alloc(
1761 maxnest * sizeof(*state));
1762 memcpy(state, state_static,
1763 MAXNEST_STATIC * sizeof(*state));
1764 } else
1765 state = parser_temp_realloc(state,
1766 maxnest * sizeof(*state));
984263bc 1767 }
99512ac4
PA
1768 level++;
1769 state[level].syntax = ARISYNTAX;
1770 state[level].parenlevel = 0;
1771 state[level].category = TSTATE_ARITH;
1772 USTPUTC(CTLARI, out);
1773 if (state[level - 1].syntax == DQSYNTAX)
1774 USTPUTC('"',out);
1775 else
1776 USTPUTC(' ',out);
984263bc
MD
1777 goto parsearith_return;
1778}
1779
1780} /* end of readtoken */
1781
1782
1783
1784#ifdef mkinit
1785RESET {
1786 tokpushback = 0;
1787 checkkwd = 0;
1788}
1789#endif
1790
1791/*
1792 * Returns true if the text contains nothing to expand (no dollar signs
1793 * or backquotes).
1794 */
1795
99512ac4 1796static int
984263bc
MD
1797noexpand(char *text)
1798{
1799 char *p;
1800 char c;
1801
1802 p = text;
1803 while ((c = *p++) != '\0') {
1804 if ( c == CTLQUOTEMARK)
1805 continue;
1806 if (c == CTLESC)
1807 p++;
1808 else if (BASESYNTAX[(int)c] == CCTL)
1809 return 0;
1810 }
1811 return 1;
1812}
1813
1814
1815/*
1816 * Return true if the argument is a legal variable name (a letter or
1817 * underscore followed by zero or more letters, underscores, and digits).
1818 */
1819
1820int
99512ac4 1821goodname(const char *name)
984263bc 1822{
99512ac4 1823 const char *p;
984263bc
MD
1824
1825 p = name;
1826 if (! is_name(*p))
1827 return 0;
1828 while (*++p) {
1829 if (! is_in_name(*p))
1830 return 0;
1831 }
1832 return 1;
1833}
1834
1835
1836/*
1837 * Called when an unexpected token is read during the parse. The argument
1838 * is the token that is expected, or -1 if more than one type of token can
1839 * occur at this point.
1840 */
1841
99512ac4 1842static void
984263bc
MD
1843synexpect(int token)
1844{
1845 char msg[64];
1846
1847 if (token >= 0) {
1848 fmtstr(msg, 64, "%s unexpected (expecting %s)",
1849 tokname[lasttoken], tokname[token]);
1850 } else {
1851 fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]);
1852 }
1853 synerror(msg);
1854}
1855
1856
99512ac4 1857static void
492efe05 1858synerror(const char *msg)
984263bc
MD
1859{
1860 if (commandname)
99512ac4
PA
1861 outfmt(out2, "%s: %d: ", commandname, startlinno);
1862 outfmt(out2, "Syntax error: %s\n", msg);
2038fb68 1863 error(NULL);
984263bc
MD
1864}
1865
99512ac4 1866static void
984263bc
MD
1867setprompt(int which)
1868{
1869 whichprompt = which;
1870
1871#ifndef NO_HISTORY
1872 if (!el)
1873#endif
99512ac4 1874 {
984263bc 1875 out2str(getprompt(NULL));
99512ac4
PA
1876 flushout(out2);
1877 }
984263bc
MD
1878}
1879
1880/*
1881 * called by editline -- any expansions to the prompt
1882 * should be added here.
1883 */
492efe05 1884const char *
984263bc
MD
1885getprompt(void *unused __unused)
1886{
3c79a5ea
PA
1887 static char ps[PROMPTLEN];
1888 const char *fmt;
99512ac4
PA
1889 const char *pwd;
1890 int i, trim;
3c79a5ea
PA
1891
1892 /*
1893 * Select prompt format.
1894 */
984263bc
MD
1895 switch (whichprompt) {
1896 case 0:
3c79a5ea
PA
1897 fmt = "";
1898 break;
984263bc 1899 case 1:
3c79a5ea
PA
1900 fmt = ps1val();
1901 break;
984263bc 1902 case 2:
3c79a5ea
PA
1903 fmt = ps2val();
1904 break;
984263bc 1905 default:
99512ac4 1906 return "??";
984263bc 1907 }
3c79a5ea
PA
1908
1909 /*
1910 * Format prompt string.
1911 */
1912 for (i = 0; (i < 127) && (*fmt != '\0'); i++, fmt++)
1913 if (*fmt == '\\')
1914 switch (*++fmt) {
1915
1916 /*
1917 * Hostname.
1918 *
1919 * \h specifies just the local hostname,
1920 * \H specifies fully-qualified hostname.
1921 */
1922 case 'h':
1923 case 'H':
1924 ps[i] = '\0';
1925 gethostname(&ps[i], PROMPTLEN - i);
1926 /* Skip to end of hostname. */
1927 trim = (*fmt == 'h') ? '.' : '\0';
1928 while ((ps[i+1] != '\0') && (ps[i+1] != trim))
1929 i++;
1930 break;
1931
1932 /*
1933 * Working directory.
1934 *
1935 * \W specifies just the final component,
1936 * \w specifies the entire path.
1937 */
1938 case 'W':
1939 case 'w':
99512ac4
PA
1940 pwd = lookupvar("PWD");
1941 if (pwd == NULL)
1942 pwd = "?";
1943 if (*fmt == 'W' &&
1944 *pwd == '/' && pwd[1] != '\0')
1945 strlcpy(&ps[i], strrchr(pwd, '/') + 1,
1946 PROMPTLEN - i);
1947 else
1948 strlcpy(&ps[i], pwd, PROMPTLEN - i);
3c79a5ea
PA
1949 /* Skip to end of path. */
1950 while (ps[i + 1] != '\0')
1951 i++;
1952 break;
1953
1954 /*
1955 * Superuser status.
1956 *
1957 * '$' for normal users, '#' for root.
1958 */
1959 case '$':
1960 ps[i] = (geteuid() != 0) ? '$' : '#';
1961 break;
1962
1963 /*
1964 * A literal \.
1965 */
1966 case '\\':
1967 ps[i] = '\\';
1968 break;
1969
1970 /*
1971 * Emit unrecognized formats verbatim.
1972 */
1973 default:
1974 ps[i++] = '\\';
1975 ps[i] = *fmt;
1976 break;
1977 }
1978 else
1979 ps[i] = *fmt;
1980 ps[i] = '\0';
1981 return (ps);
984263bc 1982}