src/parser.c

   1 /*-
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1997-2005
   5  *      Herbert Xu <herbert@gondor.apana.org.au>.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Kenneth Almquist.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #if HAVE_ALLOCA_H
  36 #include <alloca.h>
  37 #endif
  38
  39 #include <stdlib.h>
  40
  41 #include "shell.h"
  42 #include "parser.h"
  43 #include "nodes.h"
  44 #include "expand.h"     /* defines rmescapes() */
  45 #include "exec.h"       /* defines find_builtin() */
  46 #include "syntax.h"
  47 #include "options.h"
  48 #include "input.h"
  49 #include "output.h"
  50 #include "var.h"
  51 #include "error.h"
  52 #include "memalloc.h"
  53 #include "mystring.h"
  54 #include "alias.h"
  55 #include "show.h"
  56 #include "builtins.h"
  57 #include "system.h"
  58 #ifndef SMALL
  59 #include "myhistedit.h"
  60 #endif
  61
  62 /*
  63  * Shell command parser.
  64  */
  65
  66 /* values returned by readtoken */
  67 #include "token_vars.h"
  68
  69
  70
  71 /* Used by expandstr to get here-doc like behaviour. */
  72 #define FAKEEOFMARK (char *)1
  73
  74
  75
  76 struct heredoc {
  77         struct heredoc *next;   /* next here document in list */
  78         union node *here;               /* redirection node */
  79         char *eofmark;          /* string indicating end of input */
  80         int striptabs;          /* if set, strip leading tabs */
  81 };
  82
  83
  84
  85 struct heredoc *heredoclist;    /* list of here documents to read */
  86 int doprompt;                   /* if set, prompt the user */
  87 int needprompt;                 /* true if interactive and at start of line */
  88 int lasttoken;                  /* last token read */
  89 int tokpushback;                /* last token pushed back */
  90 char *wordtext;                 /* text of last word returned by readtoken */
  91 int checkkwd;
  92 struct nodelist *backquotelist;
  93 union node *redirnode;
  94 struct heredoc *heredoc;
  95 int quoteflag;                  /* set if (part of) last token was quoted */
  96
  97
  98 STATIC union node *list(int);
  99 STATIC union node *andor(void);
 100 STATIC union node *pipeline(void);
 101 STATIC union node *command(void);
 102 STATIC union node *simplecmd(void);
 103 STATIC union node *makename(void);
 104 STATIC void parsefname(void);
 105 STATIC void parseheredoc(void);
 106 STATIC int peektoken(void);
 107 STATIC int readtoken(void);
 108 STATIC int xxreadtoken(void);
 109 STATIC int readtoken1(int, char const *, char *, int);
 110 STATIC void synexpect(int) __attribute__((__noreturn__));
 111 STATIC void synerror(const char *) __attribute__((__noreturn__));
 112 STATIC void setprompt(int);
 113
 114
 115 static inline int
 116 isassignment(const char *p)
 117 {
 118         const char *q = endofname(p);
 119         if (p == q)
 120                 return 0;
 121         return *q == '=';
 122 }
 123
 124 static inline int realeofmark(const char *eofmark)
 125 {
 126         return eofmark && eofmark != FAKEEOFMARK;
 127 }
 128
 129
 130 /*
 131  * Read and parse a command.  Returns NEOF on end of file.  (NULL is a
 132  * valid parse tree indicating a blank line.)
 133  */
 134
 135 union node *
 136 parsecmd(int interact)
 137 {
 138         tokpushback = 0;
 139         checkkwd = 0;
 140         heredoclist = 0;
 141         doprompt = interact;
 142         if (doprompt)
 143                 setprompt(doprompt);
 144         needprompt = 0;
 145         return list(1);
 146 }
 147
 148
 149 STATIC union node *
 150 list(int nlflag)
 151 {
 152         union node *n1, *n2, *n3;
 153         int tok;
 154
 155         n1 = NULL;
 156         for (;;) {
 157                 switch (peektoken()) {
 158                 case TNL:
 159                         if (!(nlflag & 1))
 160                                 break;
 161                         parseheredoc();
 162                         return n1;
 163
 164                 case TEOF:
 165                         if (!n1 && (nlflag & 1))
 166                                 n1 = NEOF;
 167                         parseheredoc();
 168                         return n1;
 169                 }
 170
 171                 checkkwd = CHKNL | CHKKWD | CHKALIAS;
 172                 if (nlflag == 2 && tokendlist[peektoken()])
 173                         return n1;
 174                 nlflag |= 2;
 175
 176                 n2 = andor();
 177                 tok = readtoken();
 178                 if (tok == TBACKGND) {
 179                         if (n2->type == NPIPE) {
 180                                 n2->npipe.backgnd = 1;
 181                         } else {
 182                                 if (n2->type != NREDIR) {
 183                                         n3 = stalloc(sizeof(struct nredir));
 184                                         n3->nredir.n = n2;
 185                                         n3->nredir.redirect = NULL;
 186                                         n2 = n3;
 187                                 }
 188                                 n2->type = NBACKGND;
 189                         }
 190                 }
 191                 if (n1 == NULL) {
 192                         n1 = n2;
 193                 }
 194                 else {
 195                         n3 = (union node *)stalloc(sizeof (struct nbinary));
 196                         n3->type = NSEMI;
 197                         n3->nbinary.ch1 = n1;
 198                         n3->nbinary.ch2 = n2;
 199                         n1 = n3;
 200                 }
 201                 switch (tok) {
 202                 case TNL:
 203                 case TEOF:
 204                         tokpushback++;
 205                         /* fall through */
 206                 case TBACKGND:
 207                 case TSEMI:
 208                         break;
 209                 default:
 210                         if ((nlflag & 1))
 211                                 synexpect(-1);
 212                         tokpushback++;
 213                         return n1;
 214                 }
 215         }
 216 }
 217
 218
 219
 220 STATIC union node *
 221 andor(void)
 222 {
 223         union node *n1, *n2, *n3;
 224         int t;
 225
 226         n1 = pipeline();
 227         for (;;) {
 228                 if ((t = readtoken()) == TAND) {
 229                         t = NAND;
 230                 } else if (t == TOR) {
 231                         t = NOR;
 232                 } else {
 233                         tokpushback++;
 234                         return n1;
 235                 }
 236                 checkkwd = CHKNL | CHKKWD | CHKALIAS;
 237                 n2 = pipeline();
 238                 n3 = (union node *)stalloc(sizeof (struct nbinary));
 239                 n3->type = t;
 240                 n3->nbinary.ch1 = n1;
 241                 n3->nbinary.ch2 = n2;
 242                 n1 = n3;
 243         }
 244 }
 245
 246
 247
 248 STATIC union node *
 249 pipeline(void)
 250 {
 251         union node *n1, *n2, *pipenode;
 252         struct nodelist *lp, *prev;
 253         int negate;
 254
 255         negate = 0;
 256         TRACE(("pipeline: entered\n"));
 257         if (readtoken() == TNOT) {
 258                 negate = !negate;
 259                 checkkwd = CHKKWD | CHKALIAS;
 260         } else
 261                 tokpushback++;
 262         n1 = command();
 263         if (readtoken() == TPIPE) {
 264                 pipenode = (union node *)stalloc(sizeof (struct npipe));
 265                 pipenode->type = NPIPE;
 266                 pipenode->npipe.backgnd = 0;
 267                 lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
 268                 pipenode->npipe.cmdlist = lp;
 269                 lp->n = n1;
 270                 do {
 271                         prev = lp;
 272                         lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
 273                         checkkwd = CHKNL | CHKKWD | CHKALIAS;
 274                         lp->n = command();
 275                         prev->next = lp;
 276                 } while (readtoken() == TPIPE);
 277                 lp->next = NULL;
 278                 n1 = pipenode;
 279         }
 280         tokpushback++;
 281         if (negate) {
 282                 n2 = (union node *)stalloc(sizeof (struct nnot));
 283                 n2->type = NNOT;
 284                 n2->nnot.com = n1;
 285                 return n2;
 286         } else
 287                 return n1;
 288 }
 289
 290
 291
 292 STATIC union node *
 293 command(void)
 294 {
 295         union node *n1, *n2;
 296         union node *ap, **app;
 297         union node *cp, **cpp;
 298         union node *redir, **rpp;
 299         union node **rpp2;
 300         int t;
 301         int savelinno;
 302
 303         redir = NULL;
 304         rpp2 = &redir;
 305
 306         savelinno = plinno;
 307
 308         switch (readtoken()) {
 309         default:
 310                 synexpect(-1);
 311                 /* NOTREACHED */
 312         case TIF:
 313                 n1 = (union node *)stalloc(sizeof (struct nif));
 314                 n1->type = NIF;
 315                 n1->nif.test = list(0);
 316                 if (readtoken() != TTHEN)
 317                         synexpect(TTHEN);
 318                 n1->nif.ifpart = list(0);
 319                 n2 = n1;
 320                 while (readtoken() == TELIF) {
 321                         n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif));
 322                         n2 = n2->nif.elsepart;
 323                         n2->type = NIF;
 324                         n2->nif.test = list(0);
 325                         if (readtoken() != TTHEN)
 326                                 synexpect(TTHEN);
 327                         n2->nif.ifpart = list(0);
 328                 }
 329                 if (lasttoken == TELSE)
 330                         n2->nif.elsepart = list(0);
 331                 else {
 332                         n2->nif.elsepart = NULL;
 333                         tokpushback++;
 334                 }
 335                 t = TFI;
 336                 break;
 337         case TWHILE:
 338         case TUNTIL: {
 339                 int got;
 340                 n1 = (union node *)stalloc(sizeof (struct nbinary));
 341                 n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL;
 342                 n1->nbinary.ch1 = list(0);
 343                 if ((got=readtoken()) != TDO) {
 344 TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : ""));
 345                         synexpect(TDO);
 346                 }
 347                 n1->nbinary.ch2 = list(0);
 348                 t = TDONE;
 349                 break;
 350         }
 351         case TFOR:
 352                 if (readtoken() != TWORD || quoteflag || ! goodname(wordtext))
 353                         synerror("Bad for loop variable");
 354                 n1 = (union node *)stalloc(sizeof (struct nfor));
 355                 n1->type = NFOR;
 356                 n1->nfor.linno = savelinno;
 357                 n1->nfor.var = wordtext;
 358                 checkkwd = CHKNL | CHKKWD | CHKALIAS;
 359                 if (readtoken() == TIN) {
 360                         app = &ap;
 361                         while (readtoken() == TWORD) {
 362                                 n2 = (union node *)stalloc(sizeof (struct narg));
 363                                 n2->type = NARG;
 364                                 n2->narg.text = wordtext;
 365                                 n2->narg.backquote = backquotelist;
 366                                 *app = n2;
 367                                 app = &n2->narg.next;
 368                         }
 369                         *app = NULL;
 370                         n1->nfor.args = ap;
 371                         if (lasttoken != TNL && lasttoken != TSEMI)
 372                                 synexpect(-1);
 373                 } else {
 374                         n2 = (union node *)stalloc(sizeof (struct narg));
 375                         n2->type = NARG;
 376                         n2->narg.text = (char *)dolatstr;
 377                         n2->narg.backquote = NULL;
 378                         n2->narg.next = NULL;
 379                         n1->nfor.args = n2;
 380                         /*
 381                          * Newline or semicolon here is optional (but note
 382                          * that the original Bourne shell only allowed NL).
 383                          */
 384                         if (lasttoken != TSEMI)
 385                                 tokpushback++;
 386                 }
 387                 checkkwd = CHKNL | CHKKWD | CHKALIAS;
 388                 if (readtoken() != TDO)
 389                         synexpect(TDO);
 390                 n1->nfor.body = list(0);
 391                 t = TDONE;
 392                 break;
 393         case TCASE:
 394                 n1 = (union node *)stalloc(sizeof (struct ncase));
 395                 n1->type = NCASE;
 396                 n1->ncase.linno = savelinno;
 397                 if (readtoken() != TWORD)
 398                         synexpect(TWORD);
 399                 n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg));
 400                 n2->type = NARG;
 401                 n2->narg.text = wordtext;
 402                 n2->narg.backquote = backquotelist;
 403                 n2->narg.next = NULL;
 404                 checkkwd = CHKNL | CHKKWD | CHKALIAS;
 405                 if (readtoken() != TIN)
 406                         synexpect(TIN);
 407                 cpp = &n1->ncase.cases;
 408 next_case:
 409                 checkkwd = CHKNL | CHKKWD;
 410                 t = readtoken();
 411                 while(t != TESAC) {
 412                         if (lasttoken == TLP)
 413                                 readtoken();
 414                         *cpp = cp = (union node *)stalloc(sizeof (struct nclist));
 415                         cp->type = NCLIST;
 416                         app = &cp->nclist.pattern;
 417                         for (;;) {
 418                                 *app = ap = (union node *)stalloc(sizeof (struct narg));
 419                                 ap->type = NARG;
 420                                 ap->narg.text = wordtext;
 421                                 ap->narg.backquote = backquotelist;
 422                                 if (readtoken() != TPIPE)
 423                                         break;
 424                                 app = &ap->narg.next;
 425                                 readtoken();
 426                         }
 427                         ap->narg.next = NULL;
 428                         if (lasttoken != TRP)
 429                                 synexpect(TRP);
 430                         cp->nclist.body = list(2);
 431
 432                         cpp = &cp->nclist.next;
 433
 434                         checkkwd = CHKNL | CHKKWD;
 435                         if ((t = readtoken()) != TESAC) {
 436                                 if (t != TENDCASE)
 437                                         synexpect(TENDCASE);
 438                                 else
 439                                         goto next_case;
 440                         }
 441                 }
 442                 *cpp = NULL;
 443                 goto redir;
 444         case TLP:
 445                 n1 = (union node *)stalloc(sizeof (struct nredir));
 446                 n1->type = NSUBSHELL;
 447                 n1->nredir.linno = savelinno;
 448                 n1->nredir.n = list(0);
 449                 n1->nredir.redirect = NULL;
 450                 t = TRP;
 451                 break;
 452         case TBEGIN:
 453                 n1 = list(0);
 454                 t = TEND;
 455                 break;
 456         case TWORD:
 457         case TREDIR:
 458                 tokpushback++;
 459                 return simplecmd();
 460         }
 461
 462         if (readtoken() != t)
 463                 synexpect(t);
 464
 465 redir:
 466         /* Now check for redirection which may follow command */
 467         checkkwd = CHKKWD | CHKALIAS;
 468         rpp = rpp2;
 469         while (readtoken() == TREDIR) {
 470                 *rpp = n2 = redirnode;
 471                 rpp = &n2->nfile.next;
 472                 parsefname();
 473         }
 474         tokpushback++;
 475         *rpp = NULL;
 476         if (redir) {
 477                 if (n1->type != NSUBSHELL) {
 478                         n2 = (union node *)stalloc(sizeof (struct nredir));
 479                         n2->type = NREDIR;
 480                         n2->nredir.linno = savelinno;
 481                         n2->nredir.n = n1;
 482                         n1 = n2;
 483                 }
 484                 n1->nredir.redirect = redir;
 485         }
 486
 487         return n1;
 488 }
 489
 490
 491 STATIC union node *
 492 simplecmd(void) {
 493         union node *args, **app;
 494         union node *n = NULL;
 495         union node *vars, **vpp;
 496         union node **rpp, *redir;
 497         int savecheckkwd;
 498         int savelinno;
 499
 500         args = NULL;
 501         app = &args;
 502         vars = NULL;
 503         vpp = &vars;
 504         redir = NULL;
 505         rpp = &redir;
 506
 507         savecheckkwd = CHKALIAS;
 508         savelinno = plinno;
 509         for (;;) {
 510                 checkkwd = savecheckkwd;
 511                 switch (readtoken()) {
 512                 case TWORD:
 513                         n = (union node *)stalloc(sizeof (struct narg));
 514                         n->type = NARG;
 515                         n->narg.text = wordtext;
 516                         n->narg.backquote = backquotelist;
 517                         if (savecheckkwd && isassignment(wordtext)) {
 518                                 *vpp = n;
 519                                 vpp = &n->narg.next;
 520                         } else {
 521                                 *app = n;
 522                                 app = &n->narg.next;
 523                                 savecheckkwd = 0;
 524                         }
 525                         break;
 526                 case TREDIR:
 527                         *rpp = n = redirnode;
 528                         rpp = &n->nfile.next;
 529                         parsefname();   /* read name of redirection file */
 530                         break;
 531                 case TLP:
 532                         if (
 533                                 args && app == &args->narg.next &&
 534                                 !vars && !redir
 535                         ) {
 536                                 struct builtincmd *bcmd;
 537                                 const char *name;
 538
 539                                 /* We have a function */
 540                                 if (readtoken() != TRP)
 541                                         synexpect(TRP);
 542                                 name = n->narg.text;
 543                                 if (
 544                                         !goodname(name) || (
 545                                                 (bcmd = find_builtin(name)) &&
 546                                                 bcmd->flags & BUILTIN_SPECIAL
 547                                         )
 548                                 )
 549                                         synerror("Bad function name");
 550                                 n->type = NDEFUN;
 551                                 checkkwd = CHKNL | CHKKWD | CHKALIAS;
 552                                 n->ndefun.text = n->narg.text;
 553                                 n->ndefun.linno = plinno;
 554                                 n->ndefun.body = command();
 555                                 return n;
 556                         }
 557                         /* fall through */
 558                 default:
 559                         tokpushback++;
 560                         goto out;
 561                 }
 562         }
 563 out:
 564         *app = NULL;
 565         *vpp = NULL;
 566         *rpp = NULL;
 567         n = (union node *)stalloc(sizeof (struct ncmd));
 568         n->type = NCMD;
 569         n->ncmd.linno = savelinno;
 570         n->ncmd.args = args;
 571         n->ncmd.assign = vars;
 572         n->ncmd.redirect = redir;
 573         return n;
 574 }
 575
 576 STATIC union node *
 577 makename(void)
 578 {
 579         union node *n;
 580
 581         n = (union node *)stalloc(sizeof (struct narg));
 582         n->type = NARG;
 583         n->narg.next = NULL;
 584         n->narg.text = wordtext;
 585         n->narg.backquote = backquotelist;
 586         return n;
 587 }
 588
 589 void fixredir(union node *n, const char *text, int err)
 590         {
 591         TRACE(("Fix redir %s %d\n", text, err));
 592         if (!err)
 593                 n->ndup.vname = NULL;
 594
 595         if (is_digit(text[0]) && text[1] == '\0')
 596                 n->ndup.dupfd = digit_val(text[0]);
 597         else if (text[0] == '-' && text[1] == '\0')
 598                 n->ndup.dupfd = -1;
 599         else {
 600
 601                 if (err)
 602                         synerror("Bad fd number");
 603                 else
 604                         n->ndup.vname = makename();
 605         }
 606 }
 607
 608
 609 STATIC void
 610 parsefname(void)
 611 {
 612         union node *n = redirnode;
 613
 614         if (n->type == NHERE)
 615                 checkkwd = CHKEOFMARK;
 616         if (readtoken() != TWORD)
 617                 synexpect(-1);
 618         if (n->type == NHERE) {
 619                 struct heredoc *here = heredoc;
 620                 struct heredoc *p;
 621
 622                 if (quoteflag == 0)
 623                         n->type = NXHERE;
 624                 TRACE(("Here document %d\n", n->type));
 625                 rmescapes(wordtext);
 626                 here->eofmark = wordtext;
 627                 here->next = NULL;
 628                 if (heredoclist == NULL)
 629                         heredoclist = here;
 630                 else {
 631                         for (p = heredoclist ; p->next ; p = p->next);
 632                         p->next = here;
 633                 }
 634         } else if (n->type == NTOFD || n->type == NFROMFD) {
 635                 fixredir(n, wordtext, 0);
 636         } else {
 637                 n->nfile.fname = makename();
 638         }
 639 }
 640
 641
 642 /*
 643  * Input any here documents.
 644  */
 645
 646 STATIC void
 647 parseheredoc(void)
 648 {
 649         struct heredoc *here;
 650         union node *n;
 651
 652         here = heredoclist;
 653         heredoclist = 0;
 654
 655         while (here) {
 656                 if (needprompt) {
 657                         setprompt(2);
 658                 }
 659                 readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX,
 660                                 here->eofmark, here->striptabs);
 661                 n = (union node *)stalloc(sizeof (struct narg));
 662                 n->narg.type = NARG;
 663                 n->narg.next = NULL;
 664                 n->narg.text = wordtext;
 665                 n->narg.backquote = backquotelist;
 666                 here->here->nhere.doc = n;
 667                 here = here->next;
 668         }
 669 }
 670
 671 STATIC int
 672 peektoken(void)
 673 {
 674         int t;
 675
 676         t = readtoken();
 677         tokpushback++;
 678         return (t);
 679 }
 680
 681 STATIC int
 682 readtoken(void)
 683 {
 684         int t;
 685         int kwd = checkkwd;
 686 #ifdef DEBUG
 687         int alreadyseen = tokpushback;
 688 #endif
 689
 690 top:
 691         t = xxreadtoken();
 692
 693         /*
 694          * eat newlines
 695          */
 696         if (kwd & CHKNL) {
 697                 while (t == TNL) {
 698                         parseheredoc();
 699                         t = xxreadtoken();
 700                 }
 701         }
 702
 703         if (t != TWORD || quoteflag) {
 704                 goto out;
 705         }
 706
 707         /*
 708          * check for keywords
 709          */
 710         if (kwd & CHKKWD) {
 711                 const char *const *pp;
 712
 713                 if ((pp = findkwd(wordtext))) {
 714                         lasttoken = t = pp - parsekwd + KWDOFFSET;
 715                         TRACE(("keyword %s recognized\n", tokname[t]));
 716                         goto out;
 717                 }
 718         }
 719
 720         if (checkkwd & CHKALIAS) {
 721                 struct alias *ap;
 722                 if ((ap = lookupalias(wordtext, 1)) != NULL) {
 723                         if (*ap->val) {
 724                                 pushstring(ap->val, ap);
 725                         }
 726                         goto top;
 727                 }
 728         }
 729 out:
 730         checkkwd = 0;
 731 #ifdef DEBUG
 732         if (!alreadyseen)
 733             TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
 734         else
 735             TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
 736 #endif
 737         return (t);
 738 }
 739
 740 static void nlprompt(void)
 741 {
 742         plinno++;
 743         if (doprompt)
 744                 setprompt(2);
 745 }
 746
 747 static void nlnoprompt(void)
 748 {
 749         plinno++;
 750         needprompt = doprompt;
 751 }
 752
 753
 754 /*
 755  * Read the next input token.
 756  * If the token is a word, we set backquotelist to the list of cmds in
 757  *      backquotes.  We set quoteflag to true if any part of the word was
 758  *      quoted.
 759  * If the token is TREDIR, then we set redirnode to a structure containing
 760  *      the redirection.
 761  *
 762  * [Change comment:  here documents and internal procedures]
 763  * [Readtoken shouldn't have any arguments.  Perhaps we should make the
 764  *  word parsing code into a separate routine.  In this case, readtoken
 765  *  doesn't need to have any internal procedures, but parseword does.
 766  *  We could also make parseoperator in essence the main routine, and
 767  *  have parseword (readtoken1?) handle both words and redirection.]
 768  */
 769
 770 #define RETURN(token)   return lasttoken = token
 771
 772 STATIC int
 773 xxreadtoken(void)
 774 {
 775         int c;
 776
 777         if (tokpushback) {
 778                 tokpushback = 0;
 779                 return lasttoken;
 780         }
 781         if (needprompt) {
 782                 setprompt(2);
 783         }
 784         for (;;) {      /* until token or start of word found */
 785                 c = pgetc();
 786                 switch (c) {
 787                 case ' ': case '\t':
 788                 case PEOA:
 789                         continue;
 790                 case '#':
 791                         while ((c = pgetc()) != '\n' && c != PEOF);
 792                         pungetc();
 793                         continue;
 794                 case '\\':
 795                         if (pgetc() == '\n') {
 796                                 nlprompt();
 797                                 continue;
 798                         }
 799                         pungetc();
 800                         goto breakloop;
 801                 case '\n':
 802                         nlnoprompt();
 803                         RETURN(TNL);
 804                 case PEOF:
 805                         RETURN(TEOF);
 806                 case '&':
 807                         if (pgetc() == '&')
 808                                 RETURN(TAND);
 809                         pungetc();
 810                         RETURN(TBACKGND);
 811                 case '|':
 812                         if (pgetc() == '|')
 813                                 RETURN(TOR);
 814                         pungetc();
 815                         RETURN(TPIPE);
 816                 case ';':
 817                         if (pgetc() == ';')
 818                                 RETURN(TENDCASE);
 819                         pungetc();
 820                         RETURN(TSEMI);
 821                 case '(':
 822                         RETURN(TLP);
 823                 case ')':
 824                         RETURN(TRP);
 825                 default:
 826                         goto breakloop;
 827                 }
 828         }
 829 breakloop:
 830         return readtoken1(c, BASESYNTAX, (char *)NULL, 0);
 831 #undef RETURN
 832 }
 833
 834 static int pgetc_eatbnl(void)
 835 {
 836         int c;
 837
 838         while ((c = pgetc()) == '\\') {
 839                 if (pgetc() != '\n') {
 840                         pungetc();
 841                         break;
 842                 }
 843
 844                 nlprompt();
 845         }
 846
 847         return c;
 848 }
 849
 850
 851
 852 /*
 853  * If eofmark is NULL, read a word or a redirection symbol.  If eofmark
 854  * is not NULL, read a here document.  In the latter case, eofmark is the
 855  * word which marks the end of the document and striptabs is true if
 856  * leading tabs should be stripped from the document.  The argument firstc
 857  * is the first character of the input token or document.
 858  *
 859  * Because C does not have internal subroutines, I have simulated them
 860  * using goto's to implement the subroutine linkage.  The following macros
 861  * will run code that appears at the end of readtoken1.
 862  */
 863
 864 #define CHECKEND()      {goto checkend; checkend_return:;}
 865 #define PARSEREDIR()    {goto parseredir; parseredir_return:;}
 866 #define PARSESUB()      {goto parsesub; parsesub_return:;}
 867 #define PARSEBACKQOLD() {oldstyle = 1; goto parsebackq; parsebackq_oldreturn:;}
 868 #define PARSEBACKQNEW() {oldstyle = 0; goto parsebackq; parsebackq_newreturn:;}
 869 #define PARSEARITH()    {goto parsearith; parsearith_return:;}
 870
 871 STATIC int
 872 readtoken1(int firstc, char const *syntax, char *eofmark, int striptabs)
 873 {
 874         int c = firstc;
 875         char *out;
 876         size_t len;
 877         struct nodelist *bqlist;
 878         int quotef;
 879         int dblquote;
 880         int varnest;    /* levels of variables expansion */
 881         int arinest;    /* levels of arithmetic expansion */
 882         int parenlevel; /* levels of parens in arithmetic */
 883         int dqvarnest;  /* levels of variables expansion within double quotes */
 884         int oldstyle;
 885         /* syntax before arithmetic */
 886         char const *uninitialized_var(prevsyntax);
 887
 888         dblquote = 0;
 889         if (syntax == DQSYNTAX)
 890                 dblquote = 1;
 891         quotef = 0;
 892         bqlist = NULL;
 893         varnest = 0;
 894         arinest = 0;
 895         parenlevel = 0;
 896         dqvarnest = 0;
 897
 898         STARTSTACKSTR(out);
 899         loop: { /* for each line, until end of word */
 900 #if ATTY
 901                 if (c == '\034' && doprompt
 902                  && attyset() && ! equal(termval(), "emacs")) {
 903                         attyline();
 904                         if (syntax == BASESYNTAX)
 905                                 return readtoken();
 906                         c = pgetc();
 907                         goto loop;
 908                 }
 909 #endif
 910                 CHECKEND();     /* set c to PEOF if at end of here document */
 911                 for (;;) {      /* until end of line or end of word */
 912                         CHECKSTRSPACE(4, out);  /* permit 4 calls to USTPUTC */
 913                         switch(syntax[c]) {
 914                         case CNL:       /* '\n' */
 915                                 if (syntax == BASESYNTAX)
 916                                         goto endword;   /* exit outer loop */
 917                                 USTPUTC(c, out);
 918                                 nlprompt();
 919                                 c = pgetc();
 920                                 goto loop;              /* continue outer loop */
 921                         case CWORD:
 922                                 USTPUTC(c, out);
 923                                 break;
 924                         case CCTL:
 925                                 if (eofmark == NULL || dblquote)
 926                                         USTPUTC(CTLESC, out);
 927                                 USTPUTC(c, out);
 928                                 break;
 929                         /* backslash */
 930                         case CBACK:
 931                                 c = pgetc2();
 932                                 if (c == PEOF) {
 933                                         USTPUTC(CTLESC, out);
 934                                         USTPUTC('\\', out);
 935                                         pungetc();
 936                                 } else if (c == '\n') {
 937                                         nlprompt();
 938                                 } else {
 939                                         if (
 940                                                 dblquote &&
 941                                                 c != '\\' && c != '`' &&
 942                                                 c != '$' && (
 943                                                         c != '"' ||
 944                                                         eofmark != NULL
 945                                                 )
 946                                         ) {
 947                                                 USTPUTC('\\', out);
 948                                         }
 949                                         USTPUTC(CTLESC, out);
 950                                         USTPUTC(c, out);
 951                                         quotef++;
 952                                 }
 953                                 break;
 954                         case CSQUOTE:
 955                                 syntax = SQSYNTAX;
 956 quotemark:
 957                                 if (eofmark == NULL) {
 958                                         USTPUTC(CTLQUOTEMARK, out);
 959                                 }
 960                                 break;
 961                         case CDQUOTE:
 962                                 syntax = DQSYNTAX;
 963                                 dblquote = 1;
 964                                 goto quotemark;
 965                         case CENDQUOTE:
 966                                 if (eofmark && !varnest)
 967                                         USTPUTC(c, out);
 968                                 else {
 969                                         if (dqvarnest == 0) {
 970                                                 syntax = BASESYNTAX;
 971                                                 dblquote = 0;
 972                                         }
 973                                         quotef++;
 974                                         goto quotemark;
 975                                 }
 976                                 break;
 977                         case CVAR:      /* '$' */
 978                                 PARSESUB();             /* parse substitution */
 979                                 break;
 980                         case CENDVAR:   /* '}' */
 981                                 if (varnest > 0) {
 982                                         varnest--;
 983                                         if (dqvarnest > 0) {
 984                                                 dqvarnest--;
 985                                         }
 986                                         USTPUTC(CTLENDVAR, out);
 987                                 } else {
 988                                         USTPUTC(c, out);
 989                                 }
 990                                 break;
 991                         case CLP:       /* '(' in arithmetic */
 992                                 parenlevel++;
 993                                 USTPUTC(c, out);
 994                                 break;
 995                         case CRP:       /* ')' in arithmetic */
 996                                 if (parenlevel > 0) {
 997                                         USTPUTC(c, out);
 998                                         --parenlevel;
 999                                 } else {
1000                                         if (pgetc() == ')') {
1001                                                 USTPUTC(CTLENDARI, out);
1002                                                 if (!--arinest)
1003                                                         syntax = prevsyntax;
1004                                         } else {
1005                                                 /*
1006                                                  * unbalanced parens
1007                                                  *  (don't 2nd guess - no error)
1008                                                  */
1009                                                 pungetc();
1010                                                 USTPUTC(')', out);
1011                                         }
1012                                 }
1013                                 break;
1014                         case CBQUOTE:   /* '`' */
1015                                 PARSEBACKQOLD();
1016                                 break;
1017                         case CEOF:
1018                                 goto endword;           /* exit outer loop */
1019                         case CIGN:
1020                                 break;
1021                         default:
1022                                 if (varnest == 0)
1023                                         goto endword;   /* exit outer loop */
1024                                 if (c != PEOA) {
1025                                         USTPUTC(c, out);
1026                                 }
1027                         }
1028                         c = pgetc();
1029                 }
1030         }
1031 endword:
1032         if (syntax == ARISYNTAX)
1033                 synerror("Missing '))'");
1034         if (syntax != BASESYNTAX && eofmark == NULL)
1035                 synerror("Unterminated quoted string");
1036         if (varnest != 0) {
1037                 /* { */
1038                 synerror("Missing '}'");
1039         }
1040         USTPUTC('\0', out);
1041         len = out - (char *)stackblock();
1042         out = stackblock();
1043         if (eofmark == NULL) {
1044                 if ((c == '>' || c == '<')
1045                  && quotef == 0
1046                  && len <= 2
1047                  && (*out == '\0' || is_digit(*out))) {
1048                         PARSEREDIR();
1049                         return lasttoken = TREDIR;
1050                 } else {
1051                         pungetc();
1052                 }
1053         }
1054         quoteflag = quotef;
1055         backquotelist = bqlist;
1056         grabstackblock(len);
1057         wordtext = out;
1058         return lasttoken = TWORD;
1059 /* end of readtoken routine */
1060
1061
1062
1063 /*
1064  * Check to see whether we are at the end of the here document.  When this
1065  * is called, c is set to the first character of the next input line.  If
1066  * we are at the end of the here document, this routine sets the c to PEOF.
1067  */
1068
1069 checkend: {
1070         if (realeofmark(eofmark)) {
1071                 int markloc;
1072                 char *p;
1073
1074                 if (c == PEOA) {
1075                         c = pgetc2();
1076                 }
1077                 if (striptabs) {
1078                         while (c == '\t') {
1079                                 c = pgetc2();
1080                         }
1081                 }
1082
1083                 markloc = out - (char *)stackblock();
1084                 for (p = eofmark; STPUTC(c, out), *p; p++) {
1085                         if (c != *p)
1086                                 goto more_heredoc;
1087
1088                         c = pgetc2();
1089                 }
1090
1091                 if (c == '\n' || c == PEOF) {
1092                         c = PEOF;
1093                         nlnoprompt();
1094                 } else {
1095                         int len;
1096
1097 more_heredoc:
1098                         p = (char *)stackblock() + markloc + 1;
1099                         len = out - p;
1100
1101                         if (len) {
1102                                 len -= c < 0;
1103                                 c = p[-1];
1104
1105                                 if (len) {
1106                                         char *str;
1107
1108                                         str = alloca(len + 1);
1109                                         *(char *)mempcpy(str, p, len) = 0;
1110
1111                                         pushstring(str, NULL);
1112                                 }
1113                         }
1114                 }
1115
1116                 STADJUST((char *)stackblock() + markloc - out, out);
1117         }
1118         goto checkend_return;
1119 }
1120
1121
1122 /*
1123  * Parse a redirection operator.  The variable "out" points to a string
1124  * specifying the fd to be redirected.  The variable "c" contains the
1125  * first character of the redirection operator.
1126  */
1127
1128 parseredir: {
1129         char fd = *out;
1130         union node *np;
1131
1132         np = (union node *)stalloc(sizeof (struct nfile));
1133         if (c == '>') {
1134                 np->nfile.fd = 1;
1135                 c = pgetc();
1136                 if (c == '>')
1137                         np->type = NAPPEND;
1138                 else if (c == '|')
1139                         np->type = NCLOBBER;
1140                 else if (c == '&')
1141                         np->type = NTOFD;
1142                 else {
1143                         np->type = NTO;
1144                         pungetc();
1145                 }
1146         } else {        /* c == '<' */
1147                 np->nfile.fd = 0;
1148                 switch (c = pgetc()) {
1149                 case '<':
1150                         if (sizeof (struct nfile) != sizeof (struct nhere)) {
1151                                 np = (union node *)stalloc(sizeof (struct nhere));
1152                                 np->nfile.fd = 0;
1153                         }
1154                         np->type = NHERE;
1155                         heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc));
1156                         heredoc->here = np;
1157                         if ((c = pgetc()) == '-') {
1158                                 heredoc->striptabs = 1;
1159                         } else {
1160                                 heredoc->striptabs = 0;
1161                                 pungetc();
1162                         }
1163                         break;
1164
1165                 case '&':
1166                         np->type = NFROMFD;
1167                         break;
1168
1169                 case '>':
1170                         np->type = NFROMTO;
1171                         break;
1172
1173                 default:
1174                         np->type = NFROM;
1175                         pungetc();
1176                         break;
1177                 }
1178         }
1179         if (fd != '\0')
1180                 np->nfile.fd = digit_val(fd);
1181         redirnode = np;
1182         goto parseredir_return;
1183 }
1184
1185
1186 /*
1187  * Parse a substitution.  At this point, we have read the dollar sign
1188  * and nothing else.
1189  */
1190
1191 parsesub: {
1192         int subtype;
1193         int typeloc;
1194         char *p;
1195         static const char types[] = "}-+?=";
1196
1197         c = pgetc_eatbnl();
1198         if (
1199                 (checkkwd & CHKEOFMARK) ||
1200                 c <= PEOA  ||
1201                 (c != '(' && c != '{' && !is_name(c) && !is_special(c))
1202         ) {
1203                 USTPUTC('$', out);
1204                 pungetc();
1205         } else if (c == '(') {  /* $(command) or $((arith)) */
1206                 if (pgetc_eatbnl() == '(') {
1207                         PARSEARITH();
1208                 } else {
1209                         pungetc();
1210                         PARSEBACKQNEW();
1211                 }
1212         } else {
1213                 USTPUTC(CTLVAR, out);
1214                 typeloc = out - (char *)stackblock();
1215                 STADJUST(1, out);
1216                 subtype = VSNORMAL;
1217                 if (likely(c == '{')) {
1218                         c = pgetc_eatbnl();
1219                         subtype = 0;
1220                 }
1221 varname:
1222                 if (is_name(c)) {
1223                         do {
1224                                 STPUTC(c, out);
1225                                 c = pgetc_eatbnl();
1226                         } while (is_in_name(c));
1227                 } else if (is_digit(c)) {
1228                         do {
1229                                 STPUTC(c, out);
1230                                 c = pgetc_eatbnl();
1231                         } while (is_digit(c));
1232                 } else {
1233                         int cc = c;
1234
1235                         c = pgetc_eatbnl();
1236
1237                         if (!subtype && cc == '#') {
1238                                 subtype = VSLENGTH;
1239
1240                                 if (c == '_' || isalnum(c))
1241                                         goto varname;
1242
1243                                 cc = c;
1244                                 c = pgetc_eatbnl();
1245                                 if (cc == '}' || c != '}') {
1246                                         pungetc();
1247                                         subtype = 0;
1248                                         c = cc;
1249                                         cc = '#';
1250                                 }
1251                         }
1252
1253                         if (!is_special(cc)) {
1254                                 if (subtype == VSLENGTH)
1255                                         subtype = 0;
1256                                 goto badsub;
1257                         }
1258
1259                         USTPUTC(cc, out);
1260                 }
1261
1262                 if (subtype == 0) {
1263                         switch (c) {
1264                         case ':':
1265                                 subtype = VSNUL;
1266                                 c = pgetc_eatbnl();
1267                                 /*FALLTHROUGH*/
1268                         default:
1269                                 p = strchr(types, c);
1270                                 if (p == NULL)
1271                                         break;
1272                                 subtype |= p - types + VSNORMAL;
1273                                 break;
1274                         case '%':
1275                         case '#':
1276                                 {
1277                                         int cc = c;
1278                                         subtype = c == '#' ? VSTRIMLEFT :
1279                                                              VSTRIMRIGHT;
1280                                         c = pgetc_eatbnl();
1281                                         if (c == cc)
1282                                                 subtype++;
1283                                         else
1284                                                 pungetc();
1285                                         break;
1286                                 }
1287                         }
1288                 } else {
1289 badsub:
1290                         pungetc();
1291                 }
1292                 *((char *)stackblock() + typeloc) = subtype;
1293                 if (subtype != VSNORMAL) {
1294                         varnest++;
1295                         if (dblquote)
1296                                 dqvarnest++;
1297                 }
1298                 STPUTC('=', out);
1299         }
1300         goto parsesub_return;
1301 }
1302
1303
1304 /*
1305  * Called to parse command substitutions.  Newstyle is set if the command
1306  * is enclosed inside $(...); nlpp is a pointer to the head of the linked
1307  * list of commands (passed by reference), and savelen is the number of
1308  * characters on the top of the stack which must be preserved.
1309  */
1310
1311 parsebackq: {
1312         struct nodelist **nlpp;
1313         union node *n;
1314         char *str;
1315         size_t savelen;
1316         int uninitialized_var(saveprompt);
1317
1318         str = NULL;
1319         savelen = out - (char *)stackblock();
1320         if (savelen > 0) {
1321                 str = alloca(savelen);
1322                 memcpy(str, stackblock(), savelen);
1323         }
1324         if (oldstyle) {
1325                 /* We must read until the closing backquote, giving special
1326                    treatment to some slashes, and then push the string and
1327                    reread it as input, interpreting it normally.  */
1328                 char *pout;
1329                 int pc;
1330                 size_t psavelen;
1331                 char *pstr;
1332
1333
1334                 STARTSTACKSTR(pout);
1335                 for (;;) {
1336                         if (needprompt) {
1337                                 setprompt(2);
1338                         }
1339                         switch (pc = pgetc()) {
1340                         case '`':
1341                                 goto done;
1342
1343                         case '\\':
1344                                 if ((pc = pgetc()) == '\n') {
1345                                         nlprompt();
1346                                         /*
1347                                          * If eating a newline, avoid putting
1348                                          * the newline into the new character
1349                                          * stream (via the STPUTC after the
1350                                          * switch).
1351                                          */
1352                                         continue;
1353                                 }
1354                                 if (pc != '\\' && pc != '`' && pc != '$'
1355                                     && (!dblquote || pc != '"'))
1356                                         STPUTC('\\', pout);
1357                                 if (pc > PEOA) {
1358                                         break;
1359                                 }
1360                                 /* fall through */
1361
1362                         case PEOF:
1363                         case PEOA:
1364                                 synerror("EOF in backquote substitution");
1365
1366                         case '\n':
1367                                 nlnoprompt();
1368                                 break;
1369
1370                         default:
1371                                 break;
1372                         }
1373                         STPUTC(pc, pout);
1374                 }
1375 done:
1376                 STPUTC('\0', pout);
1377                 psavelen = pout - (char *)stackblock();
1378                 if (psavelen > 0) {
1379                         pstr = grabstackstr(pout);
1380                         setinputstring(pstr);
1381                 }
1382         }
1383         nlpp = &bqlist;
1384         while (*nlpp)
1385                 nlpp = &(*nlpp)->next;
1386         *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist));
1387         (*nlpp)->next = NULL;
1388
1389         if (oldstyle) {
1390                 saveprompt = doprompt;
1391                 doprompt = 0;
1392         }
1393
1394         n = list(2);
1395
1396         if (oldstyle)
1397                 doprompt = saveprompt;
1398         else {
1399                 if (readtoken() != TRP)
1400                         synexpect(TRP);
1401         }
1402
1403         (*nlpp)->n = n;
1404         if (oldstyle) {
1405                 /*
1406                  * Start reading from old file again, ignoring any pushed back
1407                  * tokens left from the backquote parsing
1408                  */
1409                 popfile();
1410                 tokpushback = 0;
1411         }
1412         while (stackblocksize() <= savelen)
1413                 growstackblock();
1414         STARTSTACKSTR(out);
1415         if (str) {
1416                 memcpy(out, str, savelen);
1417                 STADJUST(savelen, out);
1418         }
1419         USTPUTC(CTLBACKQ, out);
1420         if (oldstyle)
1421                 goto parsebackq_oldreturn;
1422         else
1423                 goto parsebackq_newreturn;
1424 }
1425
1426 /*
1427  * Parse an arithmetic expansion (indicate start of one and set state)
1428  */
1429 parsearith: {
1430
1431         if (++arinest == 1) {
1432                 prevsyntax = syntax;
1433                 syntax = ARISYNTAX;
1434         }
1435         USTPUTC(CTLARI, out);
1436         goto parsearith_return;
1437 }
1438
1439 } /* end of readtoken */
1440
1441
1442
1443 #ifdef mkinit
1444 INCLUDE "parser.h"
1445 #endif
1446
1447
1448 /*
1449  * Return of a legal variable name (a letter or underscore followed by zero or
1450  * more letters, underscores, and digits).
1451  */
1452
1453 char *
1454 endofname(const char *name)
1455         {
1456         char *p;
1457
1458         p = (char *) name;
1459         if (! is_name(*p))
1460                 return p;
1461         while (*++p) {
1462                 if (! is_in_name(*p))
1463                         break;
1464         }
1465         return p;
1466 }
1467
1468
1469 /*
1470  * Called when an unexpected token is read during the parse.  The argument
1471  * is the token that is expected, or -1 if more than one type of token can
1472  * occur at this point.
1473  */
1474
1475 STATIC void
1476 synexpect(int token)
1477 {
1478         char msg[64];
1479
1480         if (token >= 0) {
1481                 fmtstr(msg, 64, "%s unexpected (expecting %s)",
1482                         tokname[lasttoken], tokname[token]);
1483         } else {
1484                 fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]);
1485         }
1486         synerror(msg);
1487         /* NOTREACHED */
1488 }
1489
1490
1491 STATIC void
1492 synerror(const char *msg)
1493 {
1494         errlinno = plinno;
1495         sh_error("Syntax error: %s", msg);
1496         /* NOTREACHED */
1497 }
1498
1499 STATIC void
1500 setprompt(int which)
1501 {
1502         struct stackmark smark;
1503         int show;
1504
1505         needprompt = 0;
1506         whichprompt = which;
1507
1508 #ifdef SMALL
1509         show = 1;
1510 #else
1511         show = !el;
1512 #endif
1513         if (show) {
1514                 pushstackmark(&smark, stackblocksize());
1515                 out2str(getprompt(NULL));
1516                 popstackmark(&smark);
1517         }
1518 }
1519
1520 const char *
1521 expandstr(const char *ps)
1522 {
1523         union node n;
1524         int saveprompt;
1525
1526         /* XXX Fix (char *) cast. */
1527         setinputstring((char *)ps);
1528
1529         saveprompt = doprompt;
1530         doprompt = 0;
1531
1532         readtoken1(pgetc(), DQSYNTAX, FAKEEOFMARK, 0);
1533
1534         doprompt = saveprompt;
1535
1536         popfile();
1537
1538         n.narg.type = NARG;
1539         n.narg.next = NULL;
1540         n.narg.text = wordtext;
1541         n.narg.backquote = backquotelist;
1542
1543         expandarg(&n, NULL, EXP_QUOTED);
1544         return stackblock();
1545 }
1546
1547 /*
1548  * called by editline -- any expansions to the prompt
1549  *    should be added here.
1550  */
1551 const char *
1552 getprompt(void *unused)
1553 {
1554         const char *prompt;
1555
1556         switch (whichprompt) {
1557         default:
1558 #ifdef DEBUG
1559                 return "<internal prompt error>";
1560 #endif
1561         case 0:
1562                 return nullstr;
1563         case 1:
1564                 prompt = ps1val();
1565                 break;
1566         case 2:
1567                 prompt = ps2val();
1568                 break;
1569         }
1570
1571         return expandstr(prompt);
1572 }
1573
1574 const char *const *
1575 findkwd(const char *s)
1576 {
1577         return findstring(
1578                 s, parsekwd, sizeof(parsekwd) / sizeof(const char *)
1579         );
1580 }