2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
7 * This code is derived from software contributed to Berkeley by
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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
37 static char sccsid[] = "@(#)parser.c 8.7 (Berkeley) 5/16/95";
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
50 #include "expand.h" /* defines rmescapes() */
62 #include "exec.h" /* to check for special builtins */
64 #include "myhistedit.h"
68 * Shell command parser.
73 /* values of checkkwd variable */
78 /* values returned by readtoken */
84 struct heredoc *next; /* next here document in list */
85 union node *here; /* redirection node */
86 char *eofmark; /* string indicating end of input */
87 int striptabs; /* if set, strip leading tabs */
91 struct parser_temp *next;
96 static struct heredoc *heredoclist; /* list of here documents to read */
97 static int doprompt; /* if set, prompt the user */
98 static int needprompt; /* true if interactive and at start of line */
99 static int lasttoken; /* last token read */
100 static int tokpushback; /* last token pushed back */
101 static char *wordtext; /* text of last word returned by readtoken */
103 static struct nodelist *backquotelist;
104 static union node *redirnode;
105 static struct heredoc *heredoc;
106 static int quoteflag; /* set if (part of) last token was quoted */
107 static int startlinno; /* line # where last token started */
108 static int funclinno; /* line # where the current function started */
109 static struct parser_temp *parser_temp;
111 #define NOEOFMARK ((const char *)&heredoclist)
114 static union node *list(int);
115 static union node *andor(void);
116 static union node *pipeline(void);
117 static union node *command(void);
118 static union node *simplecmd(union node **, union node *);
119 static union node *makename(void);
120 static union node *makebinary(int type, union node *n1, union node *n2);
121 static void parsefname(void);
122 static void parseheredoc(void);
123 static int peektoken(void);
124 static int readtoken(void);
125 static int xxreadtoken(void);
126 static int readtoken1(int, const char *, const char *, int);
127 static int noexpand(char *);
128 static void consumetoken(int);
129 static void synexpect(int) __dead2;
130 static void synerror(const char *) __dead2;
131 static void setprompt(int);
132 static int pgetc_linecont(void);
136 parser_temp_alloc(size_t len)
138 struct parser_temp *t;
141 t = ckmalloc(sizeof(*t));
143 t->next = parser_temp;
145 t->data = ckmalloc(len);
152 parser_temp_realloc(void *ptr, size_t len)
154 struct parser_temp *t;
159 error("bug: parser_temp_realloc misused");
160 t->data = ckrealloc(t->data, len);
167 parser_temp_free_upto(void *ptr)
169 struct parser_temp *t;
173 while (parser_temp != NULL && !done) {
175 parser_temp = t->next;
176 done = t->data == ptr;
182 error("bug: parser_temp_free_upto misused");
187 parser_temp_free_all(void)
189 struct parser_temp *t;
192 while (parser_temp != NULL) {
194 parser_temp = t->next;
203 * Read and parse a command. Returns NEOF on end of file. (NULL is a
204 * valid parse tree indicating a blank line.)
208 parsecmd(int interact)
212 /* This assumes the parser is not re-entered,
213 * which could happen if we add command substitution on PS1/PS2.
215 parser_temp_free_all();
237 * Read and parse words for wordexp.
238 * Returns a list of NARG nodes; NULL if there are no words.
243 union node *n, *first = NULL, **pnext;
246 /* This assumes the parser is not re-entered,
247 * which could happen if we add command substitution on PS1/PS2.
249 parser_temp_free_all();
258 while ((t = readtoken()) != TEOF) {
263 pnext = &n->narg.next;
272 union node *ntop, *n1, *n2, *n3;
275 checkkwd = CHKNL | CHKKWD | CHKALIAS;
276 if (!nlflag && tokendlist[peektoken()])
282 if (tok == TBACKGND) {
283 if (n2 != NULL && n2->type == NPIPE) {
284 n2->npipe.backgnd = 1;
285 } else if (n2 != NULL && n2->type == NREDIR) {
288 n3 = (union node *)stalloc(sizeof (struct nredir));
291 n3->nredir.redirect = NULL;
297 else if (n1 == NULL) {
298 n1 = makebinary(NSEMI, ntop, n2);
302 n3 = makebinary(NSEMI, n1->nbinary.ch2, n2);
303 n1->nbinary.ch2 = n3;
316 } else if (tok == TEOF && nlflag) {
322 checkkwd = CHKNL | CHKKWD | CHKALIAS;
323 if (!nlflag && tokendlist[peektoken()])
330 pungetc(); /* push back EOF on input */
351 if ((t = readtoken()) == TAND) {
353 } else if (t == TOR) {
359 n = makebinary(t, n, pipeline());
368 union node *n1, *n2, *pipenode;
369 struct nodelist *lp, *prev;
373 checkkwd = CHKNL | CHKKWD | CHKALIAS;
374 TRACE(("pipeline: entered\n"));
375 while (readtoken() == TNOT)
379 if (readtoken() == TPIPE) {
380 pipenode = (union node *)stalloc(sizeof (struct npipe));
381 pipenode->type = NPIPE;
382 pipenode->npipe.backgnd = 0;
383 lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
384 pipenode->npipe.cmdlist = lp;
388 lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
389 checkkwd = CHKNL | CHKKWD | CHKALIAS;
397 } while (readtoken() == TPIPE);
403 n2 = (union node *)stalloc(sizeof (struct nnot));
417 union node *ap, **app;
418 union node *cp, **cpp;
419 union node *redir, **rpp;
423 checkkwd = CHKNL | CHKKWD | CHKALIAS;
429 /* Check for redirection which may precede command */
430 while (readtoken() == TREDIR) {
431 *rpp = n2 = redirnode;
432 rpp = &n2->nfile.next;
437 switch (readtoken()) {
439 n1 = (union node *)stalloc(sizeof (struct nif));
441 if ((n1->nif.test = list(0)) == NULL)
444 n1->nif.ifpart = list(0);
446 while (readtoken() == TELIF) {
447 n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif));
448 n2 = n2->nif.elsepart;
450 if ((n2->nif.test = list(0)) == NULL)
453 n2->nif.ifpart = list(0);
455 if (lasttoken == TELSE)
456 n2->nif.elsepart = list(0);
458 n2->nif.elsepart = NULL;
462 checkkwd = CHKKWD | CHKALIAS;
467 if ((n1 = list(0)) == NULL)
470 n1 = makebinary((t == TWHILE)? NWHILE : NUNTIL, n1, list(0));
472 checkkwd = CHKKWD | CHKALIAS;
475 if (readtoken() != TWORD || quoteflag || ! goodname(wordtext))
476 synerror("Bad for loop variable");
477 n1 = (union node *)stalloc(sizeof (struct nfor));
479 n1->nfor.var = wordtext;
480 while (readtoken() == TNL)
482 if (lasttoken == TWORD && ! quoteflag && equal(wordtext, "in")) {
484 while (readtoken() == TWORD) {
487 app = &n2->narg.next;
491 if (lasttoken != TNL && lasttoken != TSEMI)
494 static char argvars[5] = {
495 CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0'
497 n2 = (union node *)stalloc(sizeof (struct narg));
499 n2->narg.text = argvars;
500 n2->narg.backquote = NULL;
501 n2->narg.next = NULL;
504 * Newline or semicolon here is optional (but note
505 * that the original Bourne shell only allowed NL).
507 if (lasttoken != TNL && lasttoken != TSEMI)
510 checkkwd = CHKNL | CHKKWD | CHKALIAS;
511 if ((t = readtoken()) == TDO)
513 else if (t == TBEGIN)
517 n1->nfor.body = list(0);
519 checkkwd = CHKKWD | CHKALIAS;
522 n1 = (union node *)stalloc(sizeof (struct ncase));
525 n1->ncase.expr = makename();
526 while (readtoken() == TNL);
527 if (lasttoken != TWORD || ! equal(wordtext, "in"))
528 synerror("expecting \"in\"");
529 cpp = &n1->ncase.cases;
530 checkkwd = CHKNL | CHKKWD, readtoken();
531 while (lasttoken != TESAC) {
532 *cpp = cp = (union node *)stalloc(sizeof (struct nclist));
534 app = &cp->nclist.pattern;
535 if (lasttoken == TLP)
538 *app = ap = makename();
539 checkkwd = CHKNL | CHKKWD;
540 if (readtoken() != TPIPE)
542 app = &ap->narg.next;
545 ap->narg.next = NULL;
546 if (lasttoken != TRP)
548 cp->nclist.body = list(0);
550 checkkwd = CHKNL | CHKKWD | CHKALIAS;
551 if ((t = readtoken()) != TESAC) {
554 else if (t == TFALLTHRU)
555 cp->type = NCLISTFALLTHRU;
558 checkkwd = CHKNL | CHKKWD, readtoken();
560 cpp = &cp->nclist.next;
563 checkkwd = CHKKWD | CHKALIAS;
566 n1 = (union node *)stalloc(sizeof (struct nredir));
567 n1->type = NSUBSHELL;
568 n1->nredir.n = list(0);
569 n1->nredir.redirect = NULL;
571 checkkwd = CHKKWD | CHKALIAS;
577 checkkwd = CHKKWD | CHKALIAS;
579 /* A simple command must have at least one redirection or word. */
594 n1 = simplecmd(rpp, redir);
600 /* Now check for redirection which may follow command */
601 while (readtoken() == TREDIR) {
602 *rpp = n2 = redirnode;
603 rpp = &n2->nfile.next;
610 n2 = (union node *)stalloc(sizeof (struct nredir));
615 n1->nredir.redirect = redir;
623 simplecmd(union node **rpp, union node *redir)
625 union node *args, **app;
626 union node **orig_rpp = rpp;
627 union node *n = NULL;
631 /* If we don't have any redirections already, then we must reset */
632 /* rpp to be the address of the local redir variable. */
639 * We save the incoming value, because we need this for shell
640 * functions. There can not be a redirect or an argument between
641 * the function name and the open parenthesis.
645 savecheckkwd = CHKALIAS;
648 checkkwd = savecheckkwd;
649 if (readtoken() == TWORD) {
653 if (savecheckkwd != 0 && !isassignment(wordtext))
655 } else if (lasttoken == TREDIR) {
656 *rpp = n = redirnode;
657 rpp = &n->nfile.next;
658 parsefname(); /* read name of redirection file */
659 } else if (lasttoken == TLP && app == &args->narg.next
660 && rpp == orig_rpp) {
661 /* We have a function */
665 * - Require plain text.
666 * - Functions with '/' cannot be called.
668 * - Reject ksh extended glob patterns.
670 if (!noexpand(n->narg.text) || quoteflag ||
671 strchr(n->narg.text, '/') ||
673 n->narg.text[strlen(n->narg.text) - 1]))
674 synerror("Bad function name");
675 rmescapes(n->narg.text);
676 if (find_builtin(n->narg.text, &special) >= 0 &&
678 synerror("Cannot override a special builtin with a function");
680 n->narg.next = command();
690 n = (union node *)stalloc(sizeof (struct ncmd));
693 n->ncmd.redirect = redir;
702 n = (union node *)stalloc(sizeof (struct narg));
705 n->narg.text = wordtext;
706 n->narg.backquote = backquotelist;
711 makebinary(int type, union node *n1, union node *n2)
715 n = (union node *)stalloc(sizeof (struct nbinary));
725 checkkwd |= CHKALIAS;
729 fixredir(union node *n, const char *text, int err)
731 TRACE(("Fix redir %s %d\n", text, err));
733 n->ndup.vname = NULL;
735 if (is_digit(text[0]) && text[1] == '\0')
736 n->ndup.dupfd = digit_val(text[0]);
737 else if (text[0] == '-' && text[1] == '\0')
742 synerror("Bad fd number");
744 n->ndup.vname = makename();
752 union node *n = redirnode;
755 if (n->type == NHERE) {
756 struct heredoc *here = heredoc;
761 TRACE(("Here document %d\n", n->type));
762 if (here->striptabs) {
763 while (*wordtext == '\t')
766 if (! noexpand(wordtext))
767 synerror("Illegal eof marker for << redirection");
769 here->eofmark = wordtext;
771 if (heredoclist == NULL)
774 for (p = heredoclist ; p->next ; p = p->next);
777 } else if (n->type == NTOFD || n->type == NFROMFD) {
778 fixredir(n, wordtext, 0);
780 n->nfile.fname = makename();
786 * Input any here documents.
792 struct heredoc *here;
795 while (heredoclist) {
797 heredoclist = here->next;
802 readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX,
803 here->eofmark, here->striptabs);
805 here->here->nhere.doc = n;
825 int alreadyseen = tokpushback;
834 if (checkkwd & CHKNL) {
842 * check for keywords and aliases
844 if (t == TWORD && !quoteflag)
846 const char * const *pp;
848 if (checkkwd & CHKKWD)
849 for (pp = parsekwd; *pp; pp++) {
850 if (**pp == *wordtext && equal(*pp, wordtext))
852 lasttoken = t = pp - parsekwd + KWDOFFSET;
853 TRACE(("keyword %s recognized\n", tokname[t]));
857 if (checkkwd & CHKALIAS &&
858 (ap = lookupalias(wordtext, 1)) != NULL) {
859 pushstring(ap->val, strlen(ap->val), ap);
869 TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
871 TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
878 * Read the next input token.
879 * If the token is a word, we set backquotelist to the list of cmds in
880 * backquotes. We set quoteflag to true if any part of the word was
882 * If the token is TREDIR, then we set redirnode to a structure containing
884 * In all cases, the variable startlinno is set to the number of the line
885 * on which the token starts.
887 * [Change comment: here documents and internal procedures]
888 * [Readtoken shouldn't have any arguments. Perhaps we should make the
889 * word parsing code into a separate routine. In this case, readtoken
890 * doesn't need to have any internal procedures, but parseword does.
891 * We could also make parseoperator in essence the main routine, and
892 * have parseword (readtoken1?) handle both words and redirection.]
895 #define RETURN(token) return lasttoken = token
911 for (;;) { /* until token or start of word found */
917 while ((c = pgetc()) != '\n' && c != PEOF);
921 if (pgetc() == '\n') {
922 startlinno = ++plinno;
932 return readtoken1(c, BASESYNTAX, (char *)NULL, 0);
935 needprompt = doprompt;
940 if (pgetc_linecont() == '&')
945 if (pgetc_linecont() == '|')
950 c = pgetc_linecont();
967 #define MAXNEST_static 8
970 const char *syntax; /* *SYNTAX */
971 int parenlevel; /* levels of parentheses in arithmetic */
972 enum tokenstate_category
975 TSTATE_VAR_OLD, /* ${var+-=?}, inherits dquotes */
976 TSTATE_VAR_NEW, /* other ${var...}, own dquote state */
983 * Check to see whether we are at the end of the here document. When this
984 * is called, c is set to the first character of the next input line. If
985 * we are at the end of the here document, this routine sets the c to PEOF.
986 * The new value of c is returned.
990 checkend(int c, const char *eofmark, int striptabs)
1000 for (q = eofmark + 1; c2 = pgetc(), *q != '\0' && c2 == *q; q++)
1002 if ((c2 == PEOF || c2 == '\n') && *q == '\0') {
1006 needprompt = doprompt;
1010 pushstring(eofmark + 1, q - (eofmark + 1), NULL);
1012 } else if (c == '\n' && *eofmark == '\0') {
1015 needprompt = doprompt;
1022 * Parse a redirection operator. The variable "out" points to a string
1023 * specifying the fd to be redirected. The variable "c" contains the
1024 * first character of the redirection operator.
1028 parseredir(char *out, int c)
1033 np = (union node *)stalloc(sizeof (struct nfile));
1036 c = pgetc_linecont();
1042 np->type = NCLOBBER;
1047 } else { /* c == '<' */
1049 c = pgetc_linecont();
1051 if (sizeof (struct nfile) != sizeof (struct nhere)) {
1052 np = (union node *)stalloc(sizeof (struct nhere));
1056 heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc));
1058 if ((c = pgetc_linecont()) == '-') {
1059 heredoc->striptabs = 1;
1061 heredoc->striptabs = 0;
1064 } else if (c == '&')
1074 np->nfile.fd = digit_val(fd);
1079 * Called to parse command substitutions.
1083 parsebackq(char *out, struct nodelist **pbqlist,
1084 int oldstyle, int dblquote, int quoted)
1086 struct nodelist **nlpp;
1089 struct jmploc jmploc;
1090 struct jmploc *const savehandler = handler;
1093 const int bq_startlinno = plinno;
1094 char *volatile ostr = NULL;
1095 struct parsefile *const savetopfile = getcurrentfile();
1096 struct heredoc *const saveheredoclist = heredoclist;
1097 struct heredoc *here;
1100 if (setjmp(jmploc.loc)) {
1101 popfilesupto(savetopfile);
1106 heredoclist = saveheredoclist;
1107 handler = savehandler;
1108 if (exception == EXERROR) {
1109 startlinno = bq_startlinno;
1110 synerror("Error in command substitution");
1112 longjmp(handler->loc, 1);
1115 savelen = out - stackblock();
1117 str = ckmalloc(savelen);
1118 memcpy(str, stackblock(), savelen);
1124 /* We must read until the closing backquote, giving special
1125 treatment to some slashes, and then push the string and
1126 reread it as input, interpreting it normally. */
1132 STARTSTACKSTR(oout);
1138 CHECKSTRSPACE(2, oout);
1139 c = pgetc_linecont();
1145 if (c != '\\' && c != '`' && c != '$'
1146 && (!dblquote || c != '"'))
1147 USTPUTC('\\', oout);
1152 needprompt = doprompt;
1156 startlinno = plinno;
1157 synerror("EOF in backquote substitution");
1165 USTPUTC('\0', oout);
1166 olen = oout - stackblock();
1168 ostr = ckmalloc(olen);
1169 memcpy(ostr, stackblock(), olen);
1170 setinputstring(ostr, 1);
1175 nlpp = &(*nlpp)->next;
1176 *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist));
1177 (*nlpp)->next = NULL;
1180 saveprompt = doprompt;
1187 if (peektoken() != TEOF)
1189 doprompt = saveprompt;
1196 * Start reading from old file again, ignoring any pushed back
1197 * tokens left from the backquote parsing
1203 CHECKSTRSPACE(savelen + 1, out);
1206 memcpy(out, str, savelen);
1207 STADJUST(savelen, out);
1215 here = saveheredoclist;
1217 while (here->next != NULL)
1219 here->next = heredoclist;
1220 heredoclist = saveheredoclist;
1222 handler = savehandler;
1225 USTPUTC(CTLBACKQ | CTLQUOTE, out);
1227 USTPUTC(CTLBACKQ, out);
1233 * Called to parse a backslash escape sequence inside $'...'.
1234 * The backslash has already been read.
1237 readcstyleesc(char *out)
1245 synerror("Unterminated quoted string");
1258 case 'a': v = '\a'; break;
1259 case 'b': v = '\b'; break;
1260 case 'e': v = '\033'; break;
1261 case 'f': v = '\f'; break;
1262 case 'n': v = '\n'; break;
1263 case 'r': v = '\r'; break;
1264 case 't': v = '\t'; break;
1265 case 'v': v = '\v'; break;
1270 if (c >= '0' && c <= '9')
1271 v = (v << 4) + c - '0';
1272 else if (c >= 'A' && c <= 'F')
1273 v = (v << 4) + c - 'A' + 10;
1274 else if (c >= 'a' && c <= 'f')
1275 v = (v << 4) + c - 'a' + 10;
1281 case '0': case '1': case '2': case '3':
1282 case '4': case '5': case '6': case '7':
1285 if (c >= '0' && c <= '7') {
1289 if (c >= '0' && c <= '7') {
1299 if (c < 0x3f || c > 0x7a || c == 0x60)
1300 synerror("Bad escape sequence");
1301 if (c == '\\' && pgetc() != '\\')
1302 synerror("Bad escape sequence");
1310 n = c == 'U' ? 8 : 4;
1312 for (i = 0; i < n; i++) {
1314 if (c >= '0' && c <= '9')
1315 v = (v << 4) + c - '0';
1316 else if (c >= 'A' && c <= 'F')
1317 v = (v << 4) + c - 'A' + 10;
1318 else if (c >= 'a' && c <= 'f')
1319 v = (v << 4) + c - 'a' + 10;
1321 synerror("Bad escape sequence");
1323 if (v == 0 || (v >= 0xd800 && v <= 0xdfff))
1324 synerror("Bad escape sequence");
1325 /* We really need iconv here. */
1326 if (initial_localeisutf8 && v > 127) {
1327 CHECKSTRSPACE(4, out);
1329 * We cannot use wctomb() as the locale may have
1333 USTPUTC(0xc0 | v >> 6, out);
1334 USTPUTC(0x80 | (v & 0x3f), out);
1336 } else if (v <= 0xffff) {
1337 USTPUTC(0xe0 | v >> 12, out);
1338 USTPUTC(0x80 | ((v >> 6) & 0x3f), out);
1339 USTPUTC(0x80 | (v & 0x3f), out);
1341 } else if (v <= 0x10ffff) {
1342 USTPUTC(0xf0 | v >> 18, out);
1343 USTPUTC(0x80 | ((v >> 12) & 0x3f), out);
1344 USTPUTC(0x80 | ((v >> 6) & 0x3f), out);
1345 USTPUTC(0x80 | (v & 0x3f), out);
1353 synerror("Bad escape sequence");
1357 * We can't handle NUL bytes.
1358 * POSIX says we should skip till the closing quote.
1361 while ((c = pgetc()) != '\'') {
1365 synerror("Unterminated quoted string");
1377 if (SQSYNTAX[vc] == CCTL)
1378 USTPUTC(CTLESC, out);
1385 * If eofmark is NULL, read a word or a redirection symbol. If eofmark
1386 * is not NULL, read a here document. In the latter case, eofmark is the
1387 * word which marks the end of the document and striptabs is true if
1388 * leading tabs should be stripped from the document. The argument firstc
1389 * is the first character of the input token or document.
1391 * Because C does not have internal subroutines, I have simulated them
1392 * using goto's to implement the subroutine linkage. The following macros
1393 * will run code that appears at the end of readtoken1.
1396 #define PARSESUB() {goto parsesub; parsesub_return:;}
1397 #define PARSEARITH() {goto parsearith; parsearith_return:;}
1400 readtoken1(int firstc, char const *initialsyntax, const char *eofmark,
1406 struct nodelist *bqlist;
1411 struct tokenstate state_static[MAXNEST_static];
1412 int maxnest = MAXNEST_static;
1413 struct tokenstate *state = state_static;
1416 startlinno = plinno;
1421 state[level].syntax = initialsyntax;
1422 state[level].parenlevel = 0;
1423 state[level].category = TSTATE_TOP;
1426 loop: { /* for each line, until end of word */
1427 if (eofmark && eofmark != NOEOFMARK)
1428 /* set c to PEOF if at end of here document */
1429 c = checkend(c, eofmark, striptabs);
1430 for (;;) { /* until end of line or end of word */
1431 CHECKSTRSPACE(4, out); /* permit 4 calls to USTPUTC */
1433 synentry = state[level].syntax[c];
1436 case CNL: /* '\n' */
1438 goto endword; /* exit outer loop */
1448 goto loop; /* continue outer loop */
1451 out = readcstyleesc(out);
1459 if (eofmark == NULL || initialsyntax != SQSYNTAX)
1460 USTPUTC(CTLESC, out);
1463 case CBACK: /* backslash */
1468 } else if (c == '\n') {
1475 if (state[level].syntax == DQSYNTAX &&
1476 c != '\\' && c != '`' && c != '$' &&
1477 (c != '"' || (eofmark != NULL &&
1478 newvarnest == 0)) &&
1479 (c != '}' || state[level].category != TSTATE_VAR_OLD))
1481 if ((eofmark == NULL ||
1483 state[level].syntax == BASESYNTAX)
1484 USTPUTC(CTLQUOTEMARK, out);
1485 if (SQSYNTAX[c] == CCTL)
1486 USTPUTC(CTLESC, out);
1488 if ((eofmark == NULL ||
1490 state[level].syntax == BASESYNTAX &&
1491 state[level].category == TSTATE_VAR_OLD)
1492 USTPUTC(CTLQUOTEEND, out);
1497 USTPUTC(CTLQUOTEMARK, out);
1498 state[level].syntax = SQSYNTAX;
1502 USTPUTC(CTLQUOTEMARK, out);
1503 state[level].syntax = DQSYNTAX;
1506 if (eofmark != NULL && newvarnest == 0)
1509 if (state[level].category == TSTATE_VAR_OLD)
1510 USTPUTC(CTLQUOTEEND, out);
1511 state[level].syntax = BASESYNTAX;
1515 case CVAR: /* '$' */
1516 PARSESUB(); /* parse substitution */
1518 case CENDVAR: /* '}' */
1520 ((state[level].category == TSTATE_VAR_OLD &&
1521 state[level].syntax ==
1522 state[level - 1].syntax) ||
1523 (state[level].category == TSTATE_VAR_NEW &&
1524 state[level].syntax == BASESYNTAX))) {
1525 if (state[level].category == TSTATE_VAR_NEW)
1528 USTPUTC(CTLENDVAR, out);
1533 case CLP: /* '(' in arithmetic */
1534 state[level].parenlevel++;
1537 case CRP: /* ')' in arithmetic */
1538 if (state[level].parenlevel > 0) {
1540 --state[level].parenlevel;
1542 if (pgetc_linecont() == ')') {
1544 state[level].category == TSTATE_ARITH) {
1546 USTPUTC(CTLENDARI, out);
1552 * (don't 2nd guess - no error)
1559 case CBQUOTE: /* '`' */
1560 out = parsebackq(out, &bqlist, 1,
1561 state[level].syntax == DQSYNTAX &&
1562 (eofmark == NULL || newvarnest > 0),
1563 state[level].syntax == DQSYNTAX || state[level].syntax == ARISYNTAX);
1566 goto endword; /* exit outer loop */
1571 goto endword; /* exit outer loop */
1578 if (state[level].syntax == ARISYNTAX)
1579 synerror("Missing '))'");
1580 if (state[level].syntax != BASESYNTAX && eofmark == NULL)
1581 synerror("Unterminated quoted string");
1582 if (state[level].category == TSTATE_VAR_OLD ||
1583 state[level].category == TSTATE_VAR_NEW) {
1584 startlinno = plinno;
1585 synerror("Missing '}'");
1587 if (state != state_static)
1588 parser_temp_free_upto(state);
1590 len = out - stackblock();
1592 if (eofmark == NULL) {
1593 if ((c == '>' || c == '<')
1596 && (*out == '\0' || is_digit(*out))) {
1598 return lasttoken = TREDIR;
1604 backquotelist = bqlist;
1605 grabstackblock(len);
1607 return lasttoken = TWORD;
1608 /* end of readtoken routine */
1612 * Parse a substitution. At this point, we have read the dollar sign
1621 static const char types[] = "}-+?=";
1626 c = pgetc_linecont();
1627 if (c == '(') { /* $(command) or $((arith)) */
1628 if (pgetc_linecont() == '(') {
1632 out = parsebackq(out, &bqlist, 0,
1633 state[level].syntax == DQSYNTAX &&
1634 (eofmark == NULL || newvarnest > 0),
1635 state[level].syntax == DQSYNTAX ||
1636 state[level].syntax == ARISYNTAX);
1638 } else if (c == '{' || is_name(c) || is_special(c)) {
1639 USTPUTC(CTLVAR, out);
1640 typeloc = out - stackblock();
1641 USTPUTC(VSNORMAL, out);
1645 c = pgetc_linecont();
1649 if (!is_eof(c) && is_name(c)) {
1653 c = pgetc_linecont();
1655 } while (!is_eof(c) && is_in_name(c));
1657 strncmp(out - length, "LINENO", length) == 0) {
1658 /* Replace the variable name with the
1659 * current line number. */
1661 CHECKSTRSPACE(11, out);
1664 linno -= funclinno - 1;
1665 length = snprintf(out, 11, "%d", linno);
1671 } else if (is_digit(c)) {
1672 if (subtype != VSNORMAL) {
1675 c = pgetc_linecont();
1676 } while (is_digit(c));
1679 c = pgetc_linecont();
1681 } else if (is_special(c)) {
1683 c = pgetc_linecont();
1684 if (subtype == 0 && c1 == '#') {
1686 if (strchr(types, c) == NULL && c != ':' &&
1687 c != '#' && c != '%')
1690 c = pgetc_linecont();
1691 if (c1 != '}' && c == '}') {
1706 else if (c == '\n' || c == PEOF)
1707 synerror("Unexpected end of line in substitution");
1708 else if (BASESYNTAX[c] != CCTL)
1715 c = pgetc_linecont();
1718 p = strchr(types, c);
1720 if (c == '\n' || c == PEOF)
1721 synerror("Unexpected end of line in substitution");
1724 if (BASESYNTAX[c] != CCTL)
1728 subtype = p - types + VSNORMAL;
1734 subtype = c == '#' ? VSTRIMLEFT :
1736 c = pgetc_linecont();
1744 } else if (subtype != VSERROR) {
1745 if (subtype == VSLENGTH && c != '}')
1750 if (state[level].syntax == DQSYNTAX ||
1751 state[level].syntax == ARISYNTAX)
1753 *(stackblock() + typeloc) = subtype | flags;
1754 if (subtype != VSNORMAL) {
1755 if (level + 1 >= maxnest) {
1757 if (state == state_static) {
1758 state = parser_temp_alloc(
1759 maxnest * sizeof(*state));
1760 memcpy(state, state_static,
1761 MAXNEST_static * sizeof(*state));
1763 state = parser_temp_realloc(state,
1764 maxnest * sizeof(*state));
1767 state[level].parenlevel = 0;
1768 if (subtype == VSMINUS || subtype == VSPLUS ||
1769 subtype == VSQUESTION || subtype == VSASSIGN) {
1771 * For operators that were in the Bourne shell,
1772 * inherit the double-quote state.
1774 state[level].syntax = state[level - 1].syntax;
1775 state[level].category = TSTATE_VAR_OLD;
1778 * The other operators take a pattern,
1779 * so go to BASESYNTAX.
1780 * Also, ' and " are now special, even
1781 * in here documents.
1783 state[level].syntax = BASESYNTAX;
1784 state[level].category = TSTATE_VAR_NEW;
1788 } else if (c == '\'' && state[level].syntax == BASESYNTAX) {
1789 /* $'cstylequotes' */
1790 USTPUTC(CTLQUOTEMARK, out);
1791 state[level].syntax = SQSYNTAX;
1797 goto parsesub_return;
1802 * Parse an arithmetic expansion (indicate start of one and set state)
1806 if (level + 1 >= maxnest) {
1808 if (state == state_static) {
1809 state = parser_temp_alloc(
1810 maxnest * sizeof(*state));
1811 memcpy(state, state_static,
1812 MAXNEST_static * sizeof(*state));
1814 state = parser_temp_realloc(state,
1815 maxnest * sizeof(*state));
1818 state[level].syntax = ARISYNTAX;
1819 state[level].parenlevel = 0;
1820 state[level].category = TSTATE_ARITH;
1821 USTPUTC(CTLARI, out);
1822 if (state[level - 1].syntax == DQSYNTAX)
1826 goto parsearith_return;
1829 } /* end of readtoken */
1833 * Returns true if the text contains nothing to expand (no dollar signs
1838 noexpand(char *text)
1844 while ((c = *p++) != '\0') {
1845 if ( c == CTLQUOTEMARK)
1849 else if (BASESYNTAX[(int)c] == CCTL)
1857 * Return true if the argument is a legal variable name (a letter or
1858 * underscore followed by zero or more letters, underscores, and digits).
1862 goodname(const char *name)
1870 if (! is_in_name(*p))
1878 isassignment(const char *p)
1886 else if (!is_in_name(*p))
1894 consumetoken(int token)
1896 if (readtoken() != token)
1902 * Called when an unexpected token is read during the parse. The argument
1903 * is the token that is expected, or -1 if more than one type of token can
1904 * occur at this point.
1908 synexpect(int token)
1913 fmtstr(msg, 64, "%s unexpected (expecting %s)",
1914 tokname[lasttoken], tokname[token]);
1916 fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]);
1923 synerror(const char *msg)
1926 outfmt(out2, "%s: %d: ", commandname, startlinno);
1928 outfmt(out2, "%s: ", arg0);
1929 outfmt(out2, "Syntax error: %s\n", msg);
1930 error((char *)NULL);
1934 setprompt(int which)
1936 whichprompt = which;
1944 out2str(getprompt(NULL));
1950 pgetc_linecont(void)
1954 while ((c = pgetc_macro()) == '\\') {
1964 /* Allow the backslash to be pushed back. */
1965 pushstring("\\", 1, NULL);
1973 * called by editline -- any expansions to the prompt
1974 * should be added here.
1977 getprompt(void *unused __unused)
1979 static char ps[PROMPTLEN];
1983 static char internal_error[] = "??";
1986 * Select prompt format.
1988 switch (whichprompt) {
1999 return internal_error;
2003 * Format prompt string.
2005 for (i = 0; (i < PROMPTLEN - 1) && (*fmt != '\0'); i++, fmt++)
2012 * \h specifies just the local hostname,
2013 * \H specifies fully-qualified hostname.
2018 gethostname(&ps[i], PROMPTLEN - i - 1);
2019 ps[PROMPTLEN - 1] = '\0';
2020 /* Skip to end of hostname. */
2021 trim = (*fmt == 'h') ? '.' : '\0';
2022 while ((ps[i] != '\0') && (ps[i] != trim))
2028 * Working directory.
2030 * \W specifies just the final component,
2031 * \w specifies the entire path.
2035 pwd = lookupvar("PWD");
2036 if (pwd == NULL || *pwd == '\0')
2039 *pwd == '/' && pwd[1] != '\0')
2040 strlcpy(&ps[i], strrchr(pwd, '/') + 1,
2043 strlcpy(&ps[i], pwd, PROMPTLEN - i);
2044 /* Skip to end of path. */
2045 while (ps[i + 1] != '\0')
2052 * '$' for normal users, '#' for root.
2055 ps[i] = (geteuid() != 0) ? '$' : '#';
2066 * Emit unrecognized formats verbatim.
2070 if (i < PROMPTLEN - 2)
2082 expandstr(const char *ps)
2085 struct jmploc jmploc;
2086 struct jmploc *const savehandler = handler;
2087 const int saveprompt = doprompt;
2088 struct parsefile *const savetopfile = getcurrentfile();
2089 struct parser_temp *const saveparser_temp = parser_temp;
2090 const char *result = NULL;
2092 if (!setjmp(jmploc.loc)) {
2095 setinputstring(ps, 1);
2097 readtoken1(pgetc(), DQSYNTAX, NOEOFMARK, 0);
2098 if (backquotelist != NULL)
2099 error("Command substitution not allowed here");
2103 n.narg.text = wordtext;
2104 n.narg.backquote = backquotelist;
2106 expandarg(&n, NULL, 0);
2107 result = stackblock();
2110 handler = savehandler;
2111 doprompt = saveprompt;
2112 popfilesupto(savetopfile);
2113 if (parser_temp != saveparser_temp) {
2114 parser_temp_free_all();
2115 parser_temp = saveparser_temp;
2117 if (result != NULL) {
2119 } else if (exception == EXINT)