-
Notifications
You must be signed in to change notification settings - Fork 117
/
parser.c
2078 lines (1920 loc) · 44.7 KB
/
parser.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)parser.c 8.7 (Berkeley) 5/16/95
* $FreeBSD: src/bin/sh/parser.c,v 1.115 2011/06/18 23:58:59 jilles Exp $
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "shell.h"
#include "parser.h"
#include "nodes.h"
#include "expand.h" /* defines rmescapes() */
#include "syntax.h"
#include "options.h"
#include "input.h"
#include "output.h"
#include "var.h"
#include "error.h"
#include "memalloc.h"
#include "mystring.h"
#include "alias.h"
#include "show.h"
#include "eval.h"
#include "exec.h" /* to check for special builtins */
#ifndef NO_HISTORY
#include "myhistedit.h"
#endif
/*
* Shell command parser.
*/
#define EOFMARKLEN 79
#define PROMPTLEN 128
/* values of checkkwd variable */
#define CHKALIAS 0x1
#define CHKKWD 0x2
#define CHKNL 0x4
/* values returned by readtoken */
#include "token.h"
struct heredoc {
struct heredoc *next; /* next here document in list */
union node *here; /* redirection node */
char *eofmark; /* string indicating end of input */
int striptabs; /* if set, strip leading tabs */
};
struct parser_temp {
struct parser_temp *next;
void *data;
};
static struct heredoc *heredoclist; /* list of here documents to read */
static int doprompt; /* if set, prompt the user */
static int needprompt; /* true if interactive and at start of line */
static int lasttoken; /* last token read */
MKINIT int tokpushback; /* last token pushed back */
static char *wordtext; /* text of last word returned by readtoken */
MKINIT int checkkwd; /* 1 == check for kwds, 2 == also eat newlines */
static struct nodelist *backquotelist;
static union node *redirnode;
static struct heredoc *heredoc;
static int quoteflag; /* set if (part of) last token was quoted */
static int startlinno; /* line # where last token started */
static int funclinno; /* line # where the current function started */
static struct parser_temp *parser_temp;
static union node *list(int, int);
static union node *andor(void);
static union node *pipeline(void);
static union node *command(void);
static union node *simplecmd(union node **, union node *);
static union node *makename(void);
static void parsefname(void);
static void parseheredoc(void);
static int peektoken(void);
static int readtoken(void);
static int xxreadtoken(void);
static int readtoken1(int, char const *, char *, int);
static int noexpand(char *);
static void synexpect(int) __dead2;
static void synerror(const char *) __dead2;
static void setprompt(int);
static void *
parser_temp_alloc(size_t len)
{
struct parser_temp *t;
INTOFF;
t = ckmalloc(sizeof(*t));
t->data = NULL;
t->next = parser_temp;
parser_temp = t;
t->data = ckmalloc(len);
INTON;
return t->data;
}
static void *
parser_temp_realloc(void *ptr, size_t len)
{
struct parser_temp *t;
INTOFF;
t = parser_temp;
if (ptr != t->data)
error("bug: parser_temp_realloc misused");
t->data = ckrealloc(t->data, len);
INTON;
return t->data;
}
static void
parser_temp_free_upto(void *ptr)
{
struct parser_temp *t;
int done = 0;
INTOFF;
while (parser_temp != NULL && !done) {
t = parser_temp;
parser_temp = t->next;
done = t->data == ptr;
ckfree(t->data);
ckfree(t);
}
INTON;
if (!done)
error("bug: parser_temp_free_upto misused");
}
static void
parser_temp_free_all(void)
{
struct parser_temp *t;
INTOFF;
while (parser_temp != NULL) {
t = parser_temp;
parser_temp = t->next;
ckfree(t->data);
ckfree(t);
}
INTON;
}
/*
* Read and parse a command. Returns NEOF on end of file. (NULL is a
* valid parse tree indicating a blank line.)
*/
union node *
parsecmd(int interact)
{
int t;
/* This assumes the parser is not re-entered,
* which could happen if we add command substitution on PS1/PS2.
*/
parser_temp_free_all();
heredoclist = NULL;
tokpushback = 0;
doprompt = interact;
if (doprompt)
setprompt(1);
else
setprompt(0);
needprompt = 0;
t = readtoken();
if (t == TEOF)
return NEOF;
if (t == TNL)
return NULL;
tokpushback++;
return list(1, 1);
}
static union node *
list(int nlflag, int erflag)
{
union node *ntop, *n1, *n2, *n3;
int tok;
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (!nlflag && !erflag && tokendlist[peektoken()])
return NULL;
ntop = n1 = NULL;
for (;;) {
n2 = andor();
tok = readtoken();
if (tok == TBACKGND) {
if (n2->type == NPIPE) {
n2->npipe.backgnd = 1;
} else if (n2->type == NREDIR) {
n2->type = NBACKGND;
} else {
n3 = (union node *)stalloc(sizeof (struct nredir));
n3->type = NBACKGND;
n3->nredir.n = n2;
n3->nredir.redirect = NULL;
n2 = n3;
}
}
if (ntop == NULL)
ntop = n2;
else if (n1 == NULL) {
n1 = (union node *)stalloc(sizeof (struct nbinary));
n1->type = NSEMI;
n1->nbinary.ch1 = ntop;
n1->nbinary.ch2 = n2;
ntop = n1;
}
else {
n3 = (union node *)stalloc(sizeof (struct nbinary));
n3->type = NSEMI;
n3->nbinary.ch1 = n1->nbinary.ch2;
n3->nbinary.ch2 = n2;
n1->nbinary.ch2 = n3;
n1 = n3;
}
switch (tok) {
case TBACKGND:
case TSEMI:
tok = readtoken();
/* FALLTHROUGH */
case TNL:
if (tok == TNL) {
parseheredoc();
if (nlflag)
return ntop;
} else if (tok == TEOF && nlflag) {
parseheredoc();
return ntop;
} else {
tokpushback++;
}
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (!nlflag && !erflag && tokendlist[peektoken()])
return ntop;
break;
case TEOF:
if (heredoclist)
parseheredoc();
else
pungetc(); /* push back EOF on input */
return ntop;
default:
if (nlflag || erflag)
synexpect(-1);
tokpushback++;
return ntop;
}
}
}
static union node *
andor(void)
{
union node *n1, *n2, *n3;
int t;
n1 = pipeline();
for (;;) {
if ((t = readtoken()) == TAND) {
t = NAND;
} else if (t == TOR) {
t = NOR;
} else {
tokpushback++;
return n1;
}
n2 = pipeline();
n3 = (union node *)stalloc(sizeof (struct nbinary));
n3->type = t;
n3->nbinary.ch1 = n1;
n3->nbinary.ch2 = n2;
n1 = n3;
}
}
static union node *
pipeline(void)
{
union node *n1, *n2, *pipenode;
struct nodelist *lp, *prev;
int negate, t;
negate = 0;
checkkwd = CHKNL | CHKKWD | CHKALIAS;
TRACE(("pipeline: entered\n"));
while (readtoken() == TNOT)
negate = !negate;
tokpushback++;
n1 = command();
if (readtoken() == TPIPE) {
pipenode = (union node *)stalloc(sizeof (struct npipe));
pipenode->type = NPIPE;
pipenode->npipe.backgnd = 0;
lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
pipenode->npipe.cmdlist = lp;
lp->n = n1;
do {
prev = lp;
lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
checkkwd = CHKNL | CHKKWD | CHKALIAS;
t = readtoken();
tokpushback++;
if (t == TNOT)
lp->n = pipeline();
else
lp->n = command();
prev->next = lp;
} while (readtoken() == TPIPE);
lp->next = NULL;
n1 = pipenode;
}
tokpushback++;
if (negate) {
n2 = (union node *)stalloc(sizeof (struct nnot));
n2->type = NNOT;
n2->nnot.com = n1;
return n2;
} else
return n1;
}
static union node *
command(void)
{
union node *n1, *n2;
union node *ap, **app;
union node *cp, **cpp;
union node *redir, **rpp;
int t;
int is_subshell;
checkkwd = CHKNL | CHKKWD | CHKALIAS;
is_subshell = 0;
redir = NULL;
n1 = NULL;
rpp = &redir;
/* Check for redirection which may precede command */
while (readtoken() == TREDIR) {
*rpp = n2 = redirnode;
rpp = &n2->nfile.next;
parsefname();
}
tokpushback++;
switch (readtoken()) {
case TIF:
n1 = (union node *)stalloc(sizeof (struct nif));
n1->type = NIF;
if ((n1->nif.test = list(0, 0)) == NULL)
synexpect(-1);
if (readtoken() != TTHEN)
synexpect(TTHEN);
n1->nif.ifpart = list(0, 0);
n2 = n1;
while (readtoken() == TELIF) {
n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif));
n2 = n2->nif.elsepart;
n2->type = NIF;
if ((n2->nif.test = list(0, 0)) == NULL)
synexpect(-1);
if (readtoken() != TTHEN)
synexpect(TTHEN);
n2->nif.ifpart = list(0, 0);
}
if (lasttoken == TELSE)
n2->nif.elsepart = list(0, 0);
else {
n2->nif.elsepart = NULL;
tokpushback++;
}
if (readtoken() != TFI)
synexpect(TFI);
checkkwd = CHKKWD | CHKALIAS;
break;
case TWHILE:
case TUNTIL: {
int got;
n1 = (union node *)stalloc(sizeof (struct nbinary));
n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL;
if ((n1->nbinary.ch1 = list(0, 0)) == NULL)
synexpect(-1);
if ((got=readtoken()) != TDO) {
TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : ""));
synexpect(TDO);
}
n1->nbinary.ch2 = list(0, 0);
if (readtoken() != TDONE)
synexpect(TDONE);
checkkwd = CHKKWD | CHKALIAS;
break;
}
case TFOR:
if (readtoken() != TWORD || quoteflag || ! goodname(wordtext))
synerror("Bad for loop variable");
n1 = (union node *)stalloc(sizeof (struct nfor));
n1->type = NFOR;
n1->nfor.var = wordtext;
while (readtoken() == TNL)
;
if (lasttoken == TWORD && ! quoteflag && equal(wordtext, "in")) {
app = ≈
while (readtoken() == TWORD) {
n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
*app = n2;
app = &n2->narg.next;
}
*app = NULL;
n1->nfor.args = ap;
if (lasttoken != TNL && lasttoken != TSEMI)
synexpect(-1);
} else {
static char argvars[5] = {
CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0'
};
n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = argvars;
n2->narg.backquote = NULL;
n2->narg.next = NULL;
n1->nfor.args = n2;
/*
* Newline or semicolon here is optional (but note
* that the original Bourne shell only allowed NL).
*/
if (lasttoken != TNL && lasttoken != TSEMI)
tokpushback++;
}
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if ((t = readtoken()) == TDO)
t = TDONE;
else if (t == TBEGIN)
t = TEND;
else
synexpect(-1);
n1->nfor.body = list(0, 0);
if (readtoken() != t)
synexpect(t);
checkkwd = CHKKWD | CHKALIAS;
break;
case TCASE:
n1 = (union node *)stalloc(sizeof (struct ncase));
n1->type = NCASE;
if (readtoken() != TWORD)
synexpect(TWORD);
n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
n2->narg.next = NULL;
while (readtoken() == TNL);
if (lasttoken != TWORD || ! equal(wordtext, "in"))
synerror("expecting \"in\"");
cpp = &n1->ncase.cases;
checkkwd = CHKNL | CHKKWD, readtoken();
while (lasttoken != TESAC) {
*cpp = cp = (union node *)stalloc(sizeof (struct nclist));
cp->type = NCLIST;
app = &cp->nclist.pattern;
if (lasttoken == TLP)
readtoken();
for (;;) {
*app = ap = (union node *)stalloc(sizeof (struct narg));
ap->type = NARG;
ap->narg.text = wordtext;
ap->narg.backquote = backquotelist;
checkkwd = CHKNL | CHKKWD;
if (readtoken() != TPIPE)
break;
app = &ap->narg.next;
readtoken();
}
ap->narg.next = NULL;
if (lasttoken != TRP)
synexpect(TRP);
cp->nclist.body = list(0, 0);
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if ((t = readtoken()) != TESAC) {
if (t == TENDCASE)
;
else if (t == TFALLTHRU)
cp->type = NCLISTFALLTHRU;
else
synexpect(TENDCASE);
checkkwd = CHKNL | CHKKWD, readtoken();
}
cpp = &cp->nclist.next;
}
*cpp = NULL;
checkkwd = CHKKWD | CHKALIAS;
break;
case TLP:
n1 = (union node *)stalloc(sizeof (struct nredir));
n1->type = NSUBSHELL;
n1->nredir.n = list(0, 0);
n1->nredir.redirect = NULL;
if (readtoken() != TRP)
synexpect(TRP);
checkkwd = CHKKWD | CHKALIAS;
is_subshell = 1;
break;
case TBEGIN:
n1 = list(0, 0);
if (readtoken() != TEND)
synexpect(TEND);
checkkwd = CHKKWD | CHKALIAS;
break;
/* Handle an empty command like other simple commands. */
case TBACKGND:
case TSEMI:
case TAND:
case TOR:
/*
* An empty command before a ; doesn't make much sense, and
* should certainly be disallowed in the case of `if ;'.
*/
if (!redir)
synexpect(-1);
case TNL:
case TEOF:
case TWORD:
case TRP:
tokpushback++;
n1 = simplecmd(rpp, redir);
return n1;
default:
synexpect(-1);
}
/* Now check for redirection which may follow command */
while (readtoken() == TREDIR) {
*rpp = n2 = redirnode;
rpp = &n2->nfile.next;
parsefname();
}
tokpushback++;
*rpp = NULL;
if (redir) {
if (!is_subshell) {
n2 = (union node *)stalloc(sizeof (struct nredir));
n2->type = NREDIR;
n2->nredir.n = n1;
n1 = n2;
}
n1->nredir.redirect = redir;
}
return n1;
}
static union node *
simplecmd(union node **rpp, union node *redir)
{
union node *args, **app;
union node **orig_rpp = rpp;
union node *n = NULL;
int special;
int savecheckkwd;
/* If we don't have any redirections already, then we must reset */
/* rpp to be the address of the local redir variable. */
if (redir == NULL)
rpp = &redir;
args = NULL;
app = &args;
/*
* We save the incoming value, because we need this for shell
* functions. There can not be a redirect or an argument between
* the function name and the open parenthesis.
*/
orig_rpp = rpp;
savecheckkwd = CHKALIAS;
for (;;) {
checkkwd = savecheckkwd;
if (readtoken() == TWORD) {
n = (union node *)stalloc(sizeof (struct narg));
n->type = NARG;
n->narg.text = wordtext;
n->narg.backquote = backquotelist;
*app = n;
app = &n->narg.next;
if (savecheckkwd != 0 && !isassignment(wordtext))
savecheckkwd = 0;
} else if (lasttoken == TREDIR) {
*rpp = n = redirnode;
rpp = &n->nfile.next;
parsefname(); /* read name of redirection file */
} else if (lasttoken == TLP && app == &args->narg.next
&& rpp == orig_rpp) {
/* We have a function */
if (readtoken() != TRP)
synexpect(TRP);
funclinno = plinno;
/*
* - Require plain text.
* - Functions with '/' cannot be called.
* - Reject name=().
* - Reject ksh extended glob patterns.
*/
if (!noexpand(n->narg.text) || quoteflag ||
strchr(n->narg.text, '/') ||
strchr("!%*+-=?@}~",
n->narg.text[strlen(n->narg.text) - 1]))
synerror("Bad function name");
rmescapes(n->narg.text);
if (find_builtin(n->narg.text, &special) >= 0 &&
special)
synerror("Cannot override a special builtin with a function");
n->type = NDEFUN;
n->narg.next = command();
funclinno = 0;
return n;
} else {
tokpushback++;
break;
}
}
*app = NULL;
*rpp = NULL;
n = (union node *)stalloc(sizeof (struct ncmd));
n->type = NCMD;
n->ncmd.args = args;
n->ncmd.redirect = redir;
return n;
}
static union node *
makename(void)
{
union node *n;
n = (union node *)stalloc(sizeof (struct narg));
n->type = NARG;
n->narg.next = NULL;
n->narg.text = wordtext;
n->narg.backquote = backquotelist;
return n;
}
void
fixredir(union node *n, const char *text, int err)
{
TRACE(("Fix redir %s %d\n", text, err));
if (!err)
n->ndup.vname = NULL;
if (is_digit(text[0]) && text[1] == '\0')
n->ndup.dupfd = digit_val(text[0]);
else if (text[0] == '-' && text[1] == '\0')
n->ndup.dupfd = -1;
else {
if (err)
synerror("Bad fd number");
else
n->ndup.vname = makename();
}
}
static void
parsefname(void)
{
union node *n = redirnode;
if (readtoken() != TWORD)
synexpect(-1);
if (n->type == NHERE) {
struct heredoc *here = heredoc;
struct heredoc *p;
int i;
if (quoteflag == 0)
n->type = NXHERE;
TRACE(("Here document %d\n", n->type));
if (here->striptabs) {
while (*wordtext == '\t')
wordtext++;
}
if (! noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN)
synerror("Illegal eof marker for << redirection");
rmescapes(wordtext);
here->eofmark = wordtext;
here->next = NULL;
if (heredoclist == NULL)
heredoclist = here;
else {
for (p = heredoclist ; p->next ; p = p->next);
p->next = here;
}
} else if (n->type == NTOFD || n->type == NFROMFD) {
fixredir(n, wordtext, 0);
} else {
n->nfile.fname = makename();
}
}
/*
* Input any here documents.
*/
static void
parseheredoc(void)
{
struct heredoc *here;
union node *n;
while (heredoclist) {
here = heredoclist;
heredoclist = here->next;
if (needprompt) {
setprompt(2);
needprompt = 0;
}
readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX,
here->eofmark, here->striptabs);
n = (union node *)stalloc(sizeof (struct narg));
n->narg.type = NARG;
n->narg.next = NULL;
n->narg.text = wordtext;
n->narg.backquote = backquotelist;
here->here->nhere.doc = n;
}
}
static int
peektoken(void)
{
int t;
t = readtoken();
tokpushback++;
return (t);
}
static int
readtoken(void)
{
int t;
struct alias *ap;
#ifdef DEBUG
int alreadyseen = tokpushback;
#endif
top:
t = xxreadtoken();
/*
* eat newlines
*/
if (checkkwd & CHKNL) {
while (t == TNL) {
parseheredoc();
t = xxreadtoken();
}
}
/*
* check for keywords and aliases
*/
if (t == TWORD && !quoteflag)
{
const char * const *pp;
if (checkkwd & CHKKWD)
for (pp = parsekwd; *pp; pp++) {
if (**pp == *wordtext && equal(*pp, wordtext))
{
lasttoken = t = pp - parsekwd + KWDOFFSET;
TRACE(("keyword %s recognized\n", tokname[t]));
goto out;
}
}
if (checkkwd & CHKALIAS &&
(ap = lookupalias(wordtext, 1)) != NULL) {
pushstring(ap->val, strlen(ap->val), ap);
goto top;
}
}
out:
if (t != TNOT)
checkkwd = 0;
#ifdef DEBUG
if (!alreadyseen)
TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
else
TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
#endif
return (t);
}
/*
* Read the next input token.
* If the token is a word, we set backquotelist to the list of cmds in
* backquotes. We set quoteflag to true if any part of the word was
* quoted.
* If the token is TREDIR, then we set redirnode to a structure containing
* the redirection.
* In all cases, the variable startlinno is set to the number of the line
* on which the token starts.
*
* [Change comment: here documents and internal procedures]
* [Readtoken shouldn't have any arguments. Perhaps we should make the
* word parsing code into a separate routine. In this case, readtoken
* doesn't need to have any internal procedures, but parseword does.
* We could also make parseoperator in essence the main routine, and
* have parseword (readtoken1?) handle both words and redirection.]
*/
#define RETURN(token) return lasttoken = token
static int
xxreadtoken(void)
{
int c;
if (tokpushback) {
tokpushback = 0;
return lasttoken;
}
if (needprompt) {
setprompt(2);
needprompt = 0;
}
startlinno = plinno;
for (;;) { /* until token or start of word found */
c = pgetc_macro();
switch (c) {
case ' ': case '\t':
continue;
case '#':
while ((c = pgetc()) != '\n' && c != PEOF);
pungetc();
continue;
case '\\':
if (pgetc() == '\n') {
startlinno = ++plinno;
if (doprompt)
setprompt(2);
else
setprompt(0);
continue;
}
pungetc();
goto breakloop;
case '\n':
plinno++;
needprompt = doprompt;
RETURN(TNL);
case PEOF:
RETURN(TEOF);
case '&':
if (pgetc() == '&')
RETURN(TAND);
pungetc();
RETURN(TBACKGND);
case '|':
if (pgetc() == '|')
RETURN(TOR);
pungetc();
RETURN(TPIPE);
case ';':
c = pgetc();
if (c == ';')
RETURN(TENDCASE);
else if (c == '&')
RETURN(TFALLTHRU);
pungetc();
RETURN(TSEMI);
case '(':
RETURN(TLP);
case ')':
RETURN(TRP);
default:
goto breakloop;
}
}
breakloop:
return readtoken1(c, BASESYNTAX, NULL, 0);
#undef RETURN
}
#define MAXNEST_STATIC 8
struct tokenstate
{
const char *syntax; /* *SYNTAX */
int parenlevel; /* levels of parentheses in arithmetic */
enum tokenstate_category
{
TSTATE_TOP,
TSTATE_VAR_OLD, /* ${var+-=?}, inherits dquotes */
TSTATE_VAR_NEW, /* other ${var...}, own dquote state */
TSTATE_ARITH
} category;
};
/*
* Called to parse command substitutions.
*/
static char *
parsebackq(char *out, struct nodelist **pbqlist,
int oldstyle, int dblquote, int quoted)
{
struct nodelist **nlpp;
union node *n;
char *volatile str;
struct jmploc jmploc;
struct jmploc *const savehandler = handler;
int savelen;
int saveprompt;
const int bq_startlinno = plinno;
char *volatile ostr = NULL;
struct parsefile *const savetopfile = getcurrentfile();
struct heredoc *const saveheredoclist = heredoclist;
struct heredoc *here;
str = NULL;
if (setjmp(jmploc.loc)) {
popfilesupto(savetopfile);
if (str)
ckfree(str);
if (ostr)
ckfree(ostr);
heredoclist = saveheredoclist;
handler = savehandler;