parser.c revision 208655
1167974Sdelphij/*- 2167974Sdelphij * Copyright (c) 1991, 1993 3167974Sdelphij * The Regents of the University of California. All rights reserved. 478556Sobrien * 5351008Sdelphij * This code is derived from software contributed to Berkeley by 6351008Sdelphij * Kenneth Almquist. 778556Sobrien * 8167974Sdelphij * Redistribution and use in source and binary forms, with or without 9167974Sdelphij * modification, are permitted provided that the following conditions 10167974Sdelphij * are met: 11167974Sdelphij * 1. Redistributions of source code must retain the above copyright 12167974Sdelphij * notice, this list of conditions and the following disclaimer. 13167974Sdelphij * 2. Redistributions in binary form must reproduce the above copyright 14167974Sdelphij * notice, this list of conditions and the following disclaimer in the 15167974Sdelphij * documentation and/or other materials provided with the distribution. 1678556Sobrien * 4. Neither the name of the University nor the names of its contributors 1778556Sobrien * may be used to endorse or promote products derived from this software 1878556Sobrien * without specific prior written permission. 1978556Sobrien * 2078556Sobrien * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2178556Sobrien * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2278556Sobrien * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2378556Sobrien * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2478556Sobrien * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2578556Sobrien * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2678556Sobrien * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2778556Sobrien * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2878556Sobrien * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2978556Sobrien * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3078556Sobrien * SUCH DAMAGE. 3178556Sobrien */ 3278556Sobrien 3378556Sobrien#ifndef lint 3478556Sobrien#if 0 3578556Sobrienstatic char sccsid[] = "@(#)parser.c 8.7 (Berkeley) 5/16/95"; 3678556Sobrien#endif 3778556Sobrien#endif /* not lint */ 3878556Sobrien#include <sys/cdefs.h> 3978556Sobrien__FBSDID("$FreeBSD: head/bin/sh/parser.c 208655 2010-05-30 14:11:27Z jilles $"); 4078556Sobrien 4178556Sobrien#include <stdlib.h> 4278556Sobrien#include <unistd.h> 4378556Sobrien 4478556Sobrien#include "shell.h" 4578556Sobrien#include "parser.h" 4678556Sobrien#include "nodes.h" 4778556Sobrien#include "expand.h" /* defines rmescapes() */ 4878556Sobrien#include "syntax.h" 4978556Sobrien#include "options.h" 5078556Sobrien#include "input.h" 5178556Sobrien#include "output.h" 5278556Sobrien#include "var.h" 5378556Sobrien#include "error.h" 5478556Sobrien#include "memalloc.h" 5578556Sobrien#include "mystring.h" 5678556Sobrien#include "alias.h" 5778556Sobrien#include "show.h" 5878556Sobrien#include "eval.h" 5978556Sobrien#ifndef NO_HISTORY 6078556Sobrien#include "myhistedit.h" 6178556Sobrien#endif 6278556Sobrien 6378556Sobrien/* 6478556Sobrien * Shell command parser. 6578556Sobrien */ 6678556Sobrien 6778556Sobrien#define EOFMARKLEN 79 6878556Sobrien#define PROMPTLEN 128 6978556Sobrien 7078556Sobrien/* values returned by readtoken */ 7178556Sobrien#include "token.h" 7278556Sobrien 7378556Sobrien 7478556Sobrien 7578556Sobrienstruct heredoc { 7678556Sobrien struct heredoc *next; /* next here document in list */ 7778556Sobrien union node *here; /* redirection node */ 7878556Sobrien char *eofmark; /* string indicating end of input */ 7978556Sobrien int striptabs; /* if set, strip leading tabs */ 8078556Sobrien}; 8178556Sobrien 8278556Sobrienstruct parser_temp { 8378556Sobrien struct parser_temp *next; 8478556Sobrien void *data; 8578556Sobrien}; 8678556Sobrien 8778556Sobrien 8878556SobrienSTATIC struct heredoc *heredoclist; /* list of here documents to read */ 8978556SobrienSTATIC int doprompt; /* if set, prompt the user */ 9078556SobrienSTATIC int needprompt; /* true if interactive and at start of line */ 9178556SobrienSTATIC int lasttoken; /* last token read */ 9278556SobrienMKINIT int tokpushback; /* last token pushed back */ 9378556SobrienSTATIC char *wordtext; /* text of last word returned by readtoken */ 9478556SobrienMKINIT int checkkwd; /* 1 == check for kwds, 2 == also eat newlines */ 9578556SobrienSTATIC struct nodelist *backquotelist; 9678556SobrienSTATIC union node *redirnode; 9778556SobrienSTATIC struct heredoc *heredoc; 9878556SobrienSTATIC int quoteflag; /* set if (part of) last token was quoted */ 9978556SobrienSTATIC int startlinno; /* line # where last token started */ 10078556SobrienSTATIC int funclinno; /* line # where the current function started */ 10178556SobrienSTATIC struct parser_temp *parser_temp; 10278556Sobrien 10378556Sobrien/* XXX When 'noaliases' is set to one, no alias expansion takes place. */ 10478556Sobrienstatic int noaliases = 0; 10578556Sobrien 10678556Sobrien 10778556SobrienSTATIC union node *list(int); 10878556SobrienSTATIC union node *andor(void); 10978556SobrienSTATIC union node *pipeline(void); 11078556SobrienSTATIC union node *command(void); 11178556SobrienSTATIC union node *simplecmd(union node **, union node *); 11278556SobrienSTATIC union node *makename(void); 11378556SobrienSTATIC void parsefname(void); 11478556SobrienSTATIC void parseheredoc(void); 11578556SobrienSTATIC int peektoken(void); 11678556SobrienSTATIC int readtoken(void); 11778556SobrienSTATIC int xxreadtoken(void); 11878556SobrienSTATIC int readtoken1(int, char const *, char *, int); 11978556SobrienSTATIC int noexpand(char *); 12078556SobrienSTATIC void synexpect(int); 12178556SobrienSTATIC void synerror(const char *); 12278556SobrienSTATIC void setprompt(int); 12378556Sobrien 12478556Sobrien 12578556SobrienSTATIC void * 12678556Sobrienparser_temp_alloc(size_t len) 12778556Sobrien{ 12878556Sobrien struct parser_temp *t; 12978556Sobrien 13078556Sobrien INTOFF; 13178556Sobrien t = ckmalloc(sizeof(*t)); 13278556Sobrien t->data = NULL; 13378556Sobrien t->next = parser_temp; 13478556Sobrien parser_temp = t; 13578556Sobrien t->data = ckmalloc(len); 13678556Sobrien INTON; 13778556Sobrien return t->data; 13878556Sobrien} 13978556Sobrien 14078556Sobrien 14178556SobrienSTATIC void * 14278556Sobrienparser_temp_realloc(void *ptr, size_t len) 14378556Sobrien{ 14478556Sobrien struct parser_temp *t; 14578556Sobrien 14678556Sobrien INTOFF; 14778556Sobrien t = parser_temp; 14878556Sobrien if (ptr != t->data) 14978556Sobrien error("bug: parser_temp_realloc misused"); 15090067Ssobomax t->data = ckrealloc(t->data, len); 15178556Sobrien INTON; 15278556Sobrien return t->data; 15378556Sobrien} 15478556Sobrien 15578556Sobrien 15678556SobrienSTATIC void 15778556Sobrienparser_temp_free_upto(void *ptr) 15878556Sobrien{ 15978556Sobrien struct parser_temp *t; 16078556Sobrien int done = 0; 16178556Sobrien 16278556Sobrien INTOFF; 16378556Sobrien while (parser_temp != NULL && !done) { 16478556Sobrien t = parser_temp; 16578556Sobrien parser_temp = t->next; 16678556Sobrien done = t->data == ptr; 16778556Sobrien ckfree(t->data); 16878556Sobrien ckfree(t); 16978556Sobrien } 17078556Sobrien INTON; 17178556Sobrien if (!done) 17278556Sobrien error("bug: parser_temp_free_upto misused"); 17378556Sobrien} 17478556Sobrien 17578556Sobrien 17678556SobrienSTATIC void 17778556Sobrienparser_temp_free_all(void) 17878556Sobrien{ 17978556Sobrien struct parser_temp *t; 18078556Sobrien 18190067Ssobomax INTOFF; 18290067Ssobomax while (parser_temp != NULL) { 18390067Ssobomax t = parser_temp; 18490067Ssobomax parser_temp = t->next; 18590067Ssobomax ckfree(t->data); 18690067Ssobomax ckfree(t); 18790067Ssobomax } 18890067Ssobomax INTON; 18990067Ssobomax} 19090067Ssobomax 19190067Ssobomax 19290067Ssobomax/* 19390067Ssobomax * Read and parse a command. Returns NEOF on end of file. (NULL is a 19490067Ssobomax * valid parse tree indicating a blank line.) 19590067Ssobomax */ 19690067Ssobomax 19790067Ssobomaxunion node * 19890067Ssobomaxparsecmd(int interact) 19990067Ssobomax{ 20090067Ssobomax int t; 20190067Ssobomax 20290067Ssobomax /* This assumes the parser is not re-entered, 20390067Ssobomax * which could happen if we add command substitution on PS1/PS2. 20490067Ssobomax */ 20590067Ssobomax parser_temp_free_all(); 20690067Ssobomax 20790067Ssobomax tokpushback = 0; 20890067Ssobomax doprompt = interact; 20990067Ssobomax if (doprompt) 21090067Ssobomax setprompt(1); 21190067Ssobomax else 21290067Ssobomax setprompt(0); 21390067Ssobomax needprompt = 0; 21490067Ssobomax t = readtoken(); 21590067Ssobomax if (t == TEOF) 21690067Ssobomax return NEOF; 21790067Ssobomax if (t == TNL) 21890067Ssobomax return NULL; 21990067Ssobomax tokpushback++; 22090067Ssobomax return list(1); 22190067Ssobomax} 22290067Ssobomax 22390067Ssobomax 22490067SsobomaxSTATIC union node * 22590067Ssobomaxlist(int nlflag) 22690067Ssobomax{ 22790067Ssobomax union node *n1, *n2, *n3; 22890067Ssobomax int tok; 22990067Ssobomax 23090067Ssobomax checkkwd = 2; 23190067Ssobomax if (nlflag == 0 && tokendlist[peektoken()]) 23290067Ssobomax return NULL; 23390067Ssobomax n1 = NULL; 23490067Ssobomax for (;;) { 23590067Ssobomax n2 = andor(); 23690067Ssobomax tok = readtoken(); 23790067Ssobomax if (tok == TBACKGND) { 23890067Ssobomax if (n2->type == NCMD || n2->type == NPIPE) { 23990067Ssobomax n2->ncmd.backgnd = 1; 24090067Ssobomax } else if (n2->type == NREDIR) { 24190067Ssobomax n2->type = NBACKGND; 24290067Ssobomax } else { 24390067Ssobomax n3 = (union node *)stalloc(sizeof (struct nredir)); 24490067Ssobomax n3->type = NBACKGND; 24590067Ssobomax n3->nredir.n = n2; 24690067Ssobomax n3->nredir.redirect = NULL; 24790067Ssobomax n2 = n3; 24890067Ssobomax } 24990067Ssobomax } 25090067Ssobomax if (n1 == NULL) { 25190067Ssobomax n1 = n2; 25290067Ssobomax } 25390067Ssobomax else { 25490067Ssobomax n3 = (union node *)stalloc(sizeof (struct nbinary)); 25590067Ssobomax n3->type = NSEMI; 25690067Ssobomax n3->nbinary.ch1 = n1; 25790067Ssobomax n3->nbinary.ch2 = n2; 25890067Ssobomax n1 = n3; 25990067Ssobomax } 26090067Ssobomax switch (tok) { 26190067Ssobomax case TBACKGND: 26290067Ssobomax case TSEMI: 26390067Ssobomax tok = readtoken(); 26490067Ssobomax /* FALLTHROUGH */ 26590067Ssobomax case TNL: 26690067Ssobomax if (tok == TNL) { 267146293Sobrien parseheredoc(); 268146293Sobrien if (nlflag) 269146293Sobrien return n1; 270146293Sobrien } else { 271146293Sobrien tokpushback++; 272146293Sobrien } 273146293Sobrien checkkwd = 2; 274146293Sobrien if (tokendlist[peektoken()]) 275146293Sobrien return n1; 276146293Sobrien break; 277167974Sdelphij case TEOF: 278146293Sobrien if (heredoclist) 279146293Sobrien parseheredoc(); 280146293Sobrien else 281146293Sobrien pungetc(); /* push back EOF on input */ 282146293Sobrien return n1; 283146293Sobrien default: 284146293Sobrien if (nlflag) 285146293Sobrien synexpect(-1); 286146293Sobrien tokpushback++; 287146293Sobrien return n1; 288146293Sobrien } 289167974Sdelphij } 290167974Sdelphij} 291167974Sdelphij 292167974Sdelphij 293167974Sdelphij 294167974SdelphijSTATIC union node * 295167974Sdelphijandor(void) 296167974Sdelphij{ 297167974Sdelphij union node *n1, *n2, *n3; 298167974Sdelphij int t; 299167974Sdelphij 300167974Sdelphij n1 = pipeline(); 301167974Sdelphij for (;;) { 302167974Sdelphij if ((t = readtoken()) == TAND) { 303167974Sdelphij t = NAND; 304167974Sdelphij } else if (t == TOR) { 305167974Sdelphij t = NOR; 306167974Sdelphij } else { 307167974Sdelphij tokpushback++; 308167974Sdelphij return n1; 309167974Sdelphij } 310167974Sdelphij n2 = pipeline(); 311167974Sdelphij n3 = (union node *)stalloc(sizeof (struct nbinary)); 312167974Sdelphij n3->type = t; 313167974Sdelphij n3->nbinary.ch1 = n1; 314167974Sdelphij n3->nbinary.ch2 = n2; 315177420Sdelphij n1 = n3; 316177420Sdelphij } 317177420Sdelphij} 318177420Sdelphij 319177420Sdelphij 320215041Sobrien 321215041SobrienSTATIC union node * 322215041Sobrienpipeline(void) 323215041Sobrien{ 324215041Sobrien union node *n1, *n2, *pipenode; 325215041Sobrien struct nodelist *lp, *prev; 326215041Sobrien int negate; 327215041Sobrien 328349719Sdelphij negate = 0; 329349719Sdelphij checkkwd = 2; 330349719Sdelphij TRACE(("pipeline: entered\n")); 331349719Sdelphij while (readtoken() == TNOT) 332349719Sdelphij negate = !negate; 333349719Sdelphij tokpushback++; 334349719Sdelphij n1 = command(); 335349719Sdelphij if (readtoken() == TPIPE) { 336349719Sdelphij pipenode = (union node *)stalloc(sizeof (struct npipe)); 337349719Sdelphij pipenode->type = NPIPE; 338349719Sdelphij pipenode->npipe.backgnd = 0; 339349719Sdelphij lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 340349719Sdelphij pipenode->npipe.cmdlist = lp; 341351008Sdelphij lp->n = n1; 342351008Sdelphij do { 343351008Sdelphij prev = lp; 344351008Sdelphij lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 345351008Sdelphij lp->n = command(); 346351008Sdelphij prev->next = lp; 347351008Sdelphij } while (readtoken() == TPIPE); 348351008Sdelphij lp->next = NULL; 349351008Sdelphij n1 = pipenode; 350351008Sdelphij } 351351008Sdelphij tokpushback++; 352351008Sdelphij if (negate) { 353351008Sdelphij n2 = (union node *)stalloc(sizeof (struct nnot)); 354351008Sdelphij n2->type = NNOT; 355351008Sdelphij n2->nnot.com = n1; 356351008Sdelphij return n2; 357 } else 358 return n1; 359} 360 361 362 363STATIC union node * 364command(void) 365{ 366 union node *n1, *n2; 367 union node *ap, **app; 368 union node *cp, **cpp; 369 union node *redir, **rpp; 370 int t, negate = 0; 371 372 checkkwd = 2; 373 redir = NULL; 374 n1 = NULL; 375 rpp = &redir; 376 377 /* Check for redirection which may precede command */ 378 while (readtoken() == TREDIR) { 379 *rpp = n2 = redirnode; 380 rpp = &n2->nfile.next; 381 parsefname(); 382 } 383 tokpushback++; 384 385 while (readtoken() == TNOT) { 386 TRACE(("command: TNOT recognized\n")); 387 negate = !negate; 388 } 389 tokpushback++; 390 391 switch (readtoken()) { 392 case TIF: 393 n1 = (union node *)stalloc(sizeof (struct nif)); 394 n1->type = NIF; 395 if ((n1->nif.test = list(0)) == NULL) 396 synexpect(-1); 397 if (readtoken() != TTHEN) 398 synexpect(TTHEN); 399 n1->nif.ifpart = list(0); 400 n2 = n1; 401 while (readtoken() == TELIF) { 402 n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif)); 403 n2 = n2->nif.elsepart; 404 n2->type = NIF; 405 if ((n2->nif.test = list(0)) == NULL) 406 synexpect(-1); 407 if (readtoken() != TTHEN) 408 synexpect(TTHEN); 409 n2->nif.ifpart = list(0); 410 } 411 if (lasttoken == TELSE) 412 n2->nif.elsepart = list(0); 413 else { 414 n2->nif.elsepart = NULL; 415 tokpushback++; 416 } 417 if (readtoken() != TFI) 418 synexpect(TFI); 419 checkkwd = 1; 420 break; 421 case TWHILE: 422 case TUNTIL: { 423 int got; 424 n1 = (union node *)stalloc(sizeof (struct nbinary)); 425 n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL; 426 if ((n1->nbinary.ch1 = list(0)) == NULL) 427 synexpect(-1); 428 if ((got=readtoken()) != TDO) { 429TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : "")); 430 synexpect(TDO); 431 } 432 n1->nbinary.ch2 = list(0); 433 if (readtoken() != TDONE) 434 synexpect(TDONE); 435 checkkwd = 1; 436 break; 437 } 438 case TFOR: 439 if (readtoken() != TWORD || quoteflag || ! goodname(wordtext)) 440 synerror("Bad for loop variable"); 441 n1 = (union node *)stalloc(sizeof (struct nfor)); 442 n1->type = NFOR; 443 n1->nfor.var = wordtext; 444 while (readtoken() == TNL) 445 ; 446 if (lasttoken == TWORD && ! quoteflag && equal(wordtext, "in")) { 447 app = ≈ 448 while (readtoken() == TWORD) { 449 n2 = (union node *)stalloc(sizeof (struct narg)); 450 n2->type = NARG; 451 n2->narg.text = wordtext; 452 n2->narg.backquote = backquotelist; 453 *app = n2; 454 app = &n2->narg.next; 455 } 456 *app = NULL; 457 n1->nfor.args = ap; 458 if (lasttoken != TNL && lasttoken != TSEMI) 459 synexpect(-1); 460 } else { 461 static char argvars[5] = { 462 CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0' 463 }; 464 n2 = (union node *)stalloc(sizeof (struct narg)); 465 n2->type = NARG; 466 n2->narg.text = argvars; 467 n2->narg.backquote = NULL; 468 n2->narg.next = NULL; 469 n1->nfor.args = n2; 470 /* 471 * Newline or semicolon here is optional (but note 472 * that the original Bourne shell only allowed NL). 473 */ 474 if (lasttoken != TNL && lasttoken != TSEMI) 475 tokpushback++; 476 } 477 checkkwd = 2; 478 if ((t = readtoken()) == TDO) 479 t = TDONE; 480 else if (t == TBEGIN) 481 t = TEND; 482 else 483 synexpect(-1); 484 n1->nfor.body = list(0); 485 if (readtoken() != t) 486 synexpect(t); 487 checkkwd = 1; 488 break; 489 case TCASE: 490 n1 = (union node *)stalloc(sizeof (struct ncase)); 491 n1->type = NCASE; 492 if (readtoken() != TWORD) 493 synexpect(TWORD); 494 n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg)); 495 n2->type = NARG; 496 n2->narg.text = wordtext; 497 n2->narg.backquote = backquotelist; 498 n2->narg.next = NULL; 499 while (readtoken() == TNL); 500 if (lasttoken != TWORD || ! equal(wordtext, "in")) 501 synerror("expecting \"in\""); 502 cpp = &n1->ncase.cases; 503 noaliases = 1; /* turn off alias expansion */ 504 checkkwd = 2, readtoken(); 505 while (lasttoken != TESAC) { 506 *cpp = cp = (union node *)stalloc(sizeof (struct nclist)); 507 cp->type = NCLIST; 508 app = &cp->nclist.pattern; 509 if (lasttoken == TLP) 510 readtoken(); 511 for (;;) { 512 *app = ap = (union node *)stalloc(sizeof (struct narg)); 513 ap->type = NARG; 514 ap->narg.text = wordtext; 515 ap->narg.backquote = backquotelist; 516 if (checkkwd = 2, readtoken() != TPIPE) 517 break; 518 app = &ap->narg.next; 519 readtoken(); 520 } 521 ap->narg.next = NULL; 522 if (lasttoken != TRP) 523 noaliases = 0, synexpect(TRP); 524 cp->nclist.body = list(0); 525 526 checkkwd = 2; 527 if ((t = readtoken()) != TESAC) { 528 if (t != TENDCASE) 529 noaliases = 0, synexpect(TENDCASE); 530 else 531 checkkwd = 2, readtoken(); 532 } 533 cpp = &cp->nclist.next; 534 } 535 noaliases = 0; /* reset alias expansion */ 536 *cpp = NULL; 537 checkkwd = 1; 538 break; 539 case TLP: 540 n1 = (union node *)stalloc(sizeof (struct nredir)); 541 n1->type = NSUBSHELL; 542 n1->nredir.n = list(0); 543 n1->nredir.redirect = NULL; 544 if (readtoken() != TRP) 545 synexpect(TRP); 546 checkkwd = 1; 547 break; 548 case TBEGIN: 549 n1 = list(0); 550 if (readtoken() != TEND) 551 synexpect(TEND); 552 checkkwd = 1; 553 break; 554 /* Handle an empty command like other simple commands. */ 555 case TSEMI: 556 case TAND: 557 case TOR: 558 /* 559 * An empty command before a ; doesn't make much sense, and 560 * should certainly be disallowed in the case of `if ;'. 561 */ 562 if (!redir) 563 synexpect(-1); 564 case TNL: 565 case TEOF: 566 case TWORD: 567 case TRP: 568 tokpushback++; 569 n1 = simplecmd(rpp, redir); 570 goto checkneg; 571 default: 572 synexpect(-1); 573 } 574 575 /* Now check for redirection which may follow command */ 576 while (readtoken() == TREDIR) { 577 *rpp = n2 = redirnode; 578 rpp = &n2->nfile.next; 579 parsefname(); 580 } 581 tokpushback++; 582 *rpp = NULL; 583 if (redir) { 584 if (n1->type != NSUBSHELL) { 585 n2 = (union node *)stalloc(sizeof (struct nredir)); 586 n2->type = NREDIR; 587 n2->nredir.n = n1; 588 n1 = n2; 589 } 590 n1->nredir.redirect = redir; 591 } 592 593checkneg: 594 if (negate) { 595 n2 = (union node *)stalloc(sizeof (struct nnot)); 596 n2->type = NNOT; 597 n2->nnot.com = n1; 598 return n2; 599 } 600 else 601 return n1; 602} 603 604 605STATIC union node * 606simplecmd(union node **rpp, union node *redir) 607{ 608 union node *args, **app; 609 union node **orig_rpp = rpp; 610 union node *n = NULL, *n2; 611 int negate = 0; 612 613 /* If we don't have any redirections already, then we must reset */ 614 /* rpp to be the address of the local redir variable. */ 615 if (redir == 0) 616 rpp = &redir; 617 618 args = NULL; 619 app = &args; 620 /* 621 * We save the incoming value, because we need this for shell 622 * functions. There can not be a redirect or an argument between 623 * the function name and the open parenthesis. 624 */ 625 orig_rpp = rpp; 626 627 while (readtoken() == TNOT) { 628 TRACE(("command: TNOT recognized\n")); 629 negate = !negate; 630 } 631 tokpushback++; 632 633 for (;;) { 634 if (readtoken() == TWORD) { 635 n = (union node *)stalloc(sizeof (struct narg)); 636 n->type = NARG; 637 n->narg.text = wordtext; 638 n->narg.backquote = backquotelist; 639 *app = n; 640 app = &n->narg.next; 641 } else if (lasttoken == TREDIR) { 642 *rpp = n = redirnode; 643 rpp = &n->nfile.next; 644 parsefname(); /* read name of redirection file */ 645 } else if (lasttoken == TLP && app == &args->narg.next 646 && rpp == orig_rpp) { 647 /* We have a function */ 648 if (readtoken() != TRP) 649 synexpect(TRP); 650 funclinno = plinno; 651#ifdef notdef 652 if (! goodname(n->narg.text)) 653 synerror("Bad function name"); 654#endif 655 n->type = NDEFUN; 656 n->narg.next = command(); 657 funclinno = 0; 658 goto checkneg; 659 } else { 660 tokpushback++; 661 break; 662 } 663 } 664 *app = NULL; 665 *rpp = NULL; 666 n = (union node *)stalloc(sizeof (struct ncmd)); 667 n->type = NCMD; 668 n->ncmd.backgnd = 0; 669 n->ncmd.args = args; 670 n->ncmd.redirect = redir; 671 672checkneg: 673 if (negate) { 674 n2 = (union node *)stalloc(sizeof (struct nnot)); 675 n2->type = NNOT; 676 n2->nnot.com = n; 677 return n2; 678 } 679 else 680 return n; 681} 682 683STATIC union node * 684makename(void) 685{ 686 union node *n; 687 688 n = (union node *)stalloc(sizeof (struct narg)); 689 n->type = NARG; 690 n->narg.next = NULL; 691 n->narg.text = wordtext; 692 n->narg.backquote = backquotelist; 693 return n; 694} 695 696void fixredir(union node *n, const char *text, int err) 697{ 698 TRACE(("Fix redir %s %d\n", text, err)); 699 if (!err) 700 n->ndup.vname = NULL; 701 702 if (is_digit(text[0]) && text[1] == '\0') 703 n->ndup.dupfd = digit_val(text[0]); 704 else if (text[0] == '-' && text[1] == '\0') 705 n->ndup.dupfd = -1; 706 else { 707 708 if (err) 709 synerror("Bad fd number"); 710 else 711 n->ndup.vname = makename(); 712 } 713} 714 715 716STATIC void 717parsefname(void) 718{ 719 union node *n = redirnode; 720 721 if (readtoken() != TWORD) 722 synexpect(-1); 723 if (n->type == NHERE) { 724 struct heredoc *here = heredoc; 725 struct heredoc *p; 726 int i; 727 728 if (quoteflag == 0) 729 n->type = NXHERE; 730 TRACE(("Here document %d\n", n->type)); 731 if (here->striptabs) { 732 while (*wordtext == '\t') 733 wordtext++; 734 } 735 if (! noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN) 736 synerror("Illegal eof marker for << redirection"); 737 rmescapes(wordtext); 738 here->eofmark = wordtext; 739 here->next = NULL; 740 if (heredoclist == NULL) 741 heredoclist = here; 742 else { 743 for (p = heredoclist ; p->next ; p = p->next); 744 p->next = here; 745 } 746 } else if (n->type == NTOFD || n->type == NFROMFD) { 747 fixredir(n, wordtext, 0); 748 } else { 749 n->nfile.fname = makename(); 750 } 751} 752 753 754/* 755 * Input any here documents. 756 */ 757 758STATIC void 759parseheredoc(void) 760{ 761 struct heredoc *here; 762 union node *n; 763 764 while (heredoclist) { 765 here = heredoclist; 766 heredoclist = here->next; 767 if (needprompt) { 768 setprompt(2); 769 needprompt = 0; 770 } 771 readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX, 772 here->eofmark, here->striptabs); 773 n = (union node *)stalloc(sizeof (struct narg)); 774 n->narg.type = NARG; 775 n->narg.next = NULL; 776 n->narg.text = wordtext; 777 n->narg.backquote = backquotelist; 778 here->here->nhere.doc = n; 779 } 780} 781 782STATIC int 783peektoken(void) 784{ 785 int t; 786 787 t = readtoken(); 788 tokpushback++; 789 return (t); 790} 791 792STATIC int 793readtoken(void) 794{ 795 int t; 796 int savecheckkwd = checkkwd; 797 struct alias *ap; 798#ifdef DEBUG 799 int alreadyseen = tokpushback; 800#endif 801 802 top: 803 t = xxreadtoken(); 804 805 if (checkkwd) { 806 /* 807 * eat newlines 808 */ 809 if (checkkwd == 2) { 810 checkkwd = 0; 811 while (t == TNL) { 812 parseheredoc(); 813 t = xxreadtoken(); 814 } 815 } else 816 checkkwd = 0; 817 /* 818 * check for keywords and aliases 819 */ 820 if (t == TWORD && !quoteflag) 821 { 822 const char * const *pp; 823 824 for (pp = parsekwd; *pp; pp++) { 825 if (**pp == *wordtext && equal(*pp, wordtext)) 826 { 827 lasttoken = t = pp - parsekwd + KWDOFFSET; 828 TRACE(("keyword %s recognized\n", tokname[t])); 829 goto out; 830 } 831 } 832 if (noaliases == 0 && 833 (ap = lookupalias(wordtext, 1)) != NULL) { 834 pushstring(ap->val, strlen(ap->val), ap); 835 checkkwd = savecheckkwd; 836 goto top; 837 } 838 } 839out: 840 checkkwd = (t == TNOT) ? savecheckkwd : 0; 841 } 842#ifdef DEBUG 843 if (!alreadyseen) 844 TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); 845 else 846 TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); 847#endif 848 return (t); 849} 850 851 852/* 853 * Read the next input token. 854 * If the token is a word, we set backquotelist to the list of cmds in 855 * backquotes. We set quoteflag to true if any part of the word was 856 * quoted. 857 * If the token is TREDIR, then we set redirnode to a structure containing 858 * the redirection. 859 * In all cases, the variable startlinno is set to the number of the line 860 * on which the token starts. 861 * 862 * [Change comment: here documents and internal procedures] 863 * [Readtoken shouldn't have any arguments. Perhaps we should make the 864 * word parsing code into a separate routine. In this case, readtoken 865 * doesn't need to have any internal procedures, but parseword does. 866 * We could also make parseoperator in essence the main routine, and 867 * have parseword (readtoken1?) handle both words and redirection.] 868 */ 869 870#define RETURN(token) return lasttoken = token 871 872STATIC int 873xxreadtoken(void) 874{ 875 int c; 876 877 if (tokpushback) { 878 tokpushback = 0; 879 return lasttoken; 880 } 881 if (needprompt) { 882 setprompt(2); 883 needprompt = 0; 884 } 885 startlinno = plinno; 886 for (;;) { /* until token or start of word found */ 887 c = pgetc_macro(); 888 if (c == ' ' || c == '\t') 889 continue; /* quick check for white space first */ 890 switch (c) { 891 case ' ': case '\t': 892 continue; 893 case '#': 894 while ((c = pgetc()) != '\n' && c != PEOF); 895 pungetc(); 896 continue; 897 case '\\': 898 if (pgetc() == '\n') { 899 startlinno = ++plinno; 900 if (doprompt) 901 setprompt(2); 902 else 903 setprompt(0); 904 continue; 905 } 906 pungetc(); 907 goto breakloop; 908 case '\n': 909 plinno++; 910 needprompt = doprompt; 911 RETURN(TNL); 912 case PEOF: 913 RETURN(TEOF); 914 case '&': 915 if (pgetc() == '&') 916 RETURN(TAND); 917 pungetc(); 918 RETURN(TBACKGND); 919 case '|': 920 if (pgetc() == '|') 921 RETURN(TOR); 922 pungetc(); 923 RETURN(TPIPE); 924 case ';': 925 if (pgetc() == ';') 926 RETURN(TENDCASE); 927 pungetc(); 928 RETURN(TSEMI); 929 case '(': 930 RETURN(TLP); 931 case ')': 932 RETURN(TRP); 933 default: 934 goto breakloop; 935 } 936 } 937breakloop: 938 return readtoken1(c, BASESYNTAX, (char *)NULL, 0); 939#undef RETURN 940} 941 942 943#define MAXNEST_STATIC 8 944struct tokenstate 945{ 946 const char *syntax; /* *SYNTAX */ 947 int parenlevel; /* levels of parentheses in arithmetic */ 948 enum tokenstate_category 949 { 950 TSTATE_TOP, 951 TSTATE_VAR_OLD, /* ${var+-=?}, inherits dquotes */ 952 TSTATE_VAR_NEW, /* other ${var...}, own dquote state */ 953 TSTATE_ARITH 954 } category; 955}; 956 957 958/* 959 * Called to parse command substitutions. 960 */ 961 962STATIC char * 963parsebackq(char *out, struct nodelist **pbqlist, 964 int oldstyle, int dblquote, int quoted) 965{ 966 struct nodelist **nlpp; 967 union node *n; 968 char *volatile str; 969 struct jmploc jmploc; 970 struct jmploc *const savehandler = handler; 971 int savelen; 972 int saveprompt; 973 const int bq_startlinno = plinno; 974 char *volatile ostr = NULL; 975 struct parsefile *const savetopfile = getcurrentfile(); 976 struct heredoc *const saveheredoclist = heredoclist; 977 struct heredoc *here; 978 979 str = NULL; 980 if (setjmp(jmploc.loc)) { 981 popfilesupto(savetopfile); 982 if (str) 983 ckfree(str); 984 if (ostr) 985 ckfree(ostr); 986 heredoclist = saveheredoclist; 987 handler = savehandler; 988 if (exception == EXERROR) { 989 startlinno = bq_startlinno; 990 synerror("Error in command substitution"); 991 } 992 longjmp(handler->loc, 1); 993 } 994 INTOFF; 995 savelen = out - stackblock(); 996 if (savelen > 0) { 997 str = ckmalloc(savelen); 998 memcpy(str, stackblock(), savelen); 999 } 1000 handler = &jmploc; 1001 heredoclist = NULL; 1002 INTON; 1003 if (oldstyle) { 1004 /* We must read until the closing backquote, giving special 1005 treatment to some slashes, and then push the string and 1006 reread it as input, interpreting it normally. */ 1007 char *oout; 1008 int c; 1009 int olen; 1010 1011 1012 STARTSTACKSTR(oout); 1013 for (;;) { 1014 if (needprompt) { 1015 setprompt(2); 1016 needprompt = 0; 1017 } 1018 switch (c = pgetc()) { 1019 case '`': 1020 goto done; 1021 1022 case '\\': 1023 if ((c = pgetc()) == '\n') { 1024 plinno++; 1025 if (doprompt) 1026 setprompt(2); 1027 else 1028 setprompt(0); 1029 /* 1030 * If eating a newline, avoid putting 1031 * the newline into the new character 1032 * stream (via the STPUTC after the 1033 * switch). 1034 */ 1035 continue; 1036 } 1037 if (c != '\\' && c != '`' && c != '$' 1038 && (!dblquote || c != '"')) 1039 STPUTC('\\', oout); 1040 break; 1041 1042 case '\n': 1043 plinno++; 1044 needprompt = doprompt; 1045 break; 1046 1047 case PEOF: 1048 startlinno = plinno; 1049 synerror("EOF in backquote substitution"); 1050 break; 1051 1052 default: 1053 break; 1054 } 1055 STPUTC(c, oout); 1056 } 1057done: 1058 STPUTC('\0', oout); 1059 olen = oout - stackblock(); 1060 INTOFF; 1061 ostr = ckmalloc(olen); 1062 memcpy(ostr, stackblock(), olen); 1063 setinputstring(ostr, 1); 1064 INTON; 1065 } 1066 nlpp = pbqlist; 1067 while (*nlpp) 1068 nlpp = &(*nlpp)->next; 1069 *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 1070 (*nlpp)->next = NULL; 1071 1072 if (oldstyle) { 1073 saveprompt = doprompt; 1074 doprompt = 0; 1075 } 1076 1077 n = list(0); 1078 1079 if (oldstyle) 1080 doprompt = saveprompt; 1081 else { 1082 if (readtoken() != TRP) 1083 synexpect(TRP); 1084 } 1085 1086 (*nlpp)->n = n; 1087 if (oldstyle) { 1088 /* 1089 * Start reading from old file again, ignoring any pushed back 1090 * tokens left from the backquote parsing 1091 */ 1092 popfile(); 1093 tokpushback = 0; 1094 } 1095 while (stackblocksize() <= savelen) 1096 growstackblock(); 1097 STARTSTACKSTR(out); 1098 INTOFF; 1099 if (str) { 1100 memcpy(out, str, savelen); 1101 STADJUST(savelen, out); 1102 ckfree(str); 1103 str = NULL; 1104 } 1105 if (ostr) { 1106 ckfree(ostr); 1107 ostr = NULL; 1108 } 1109 here = saveheredoclist; 1110 if (here != NULL) { 1111 while (here->next != NULL) 1112 here = here->next; 1113 here->next = heredoclist; 1114 heredoclist = saveheredoclist; 1115 } 1116 handler = savehandler; 1117 INTON; 1118 if (quoted) 1119 USTPUTC(CTLBACKQ | CTLQUOTE, out); 1120 else 1121 USTPUTC(CTLBACKQ, out); 1122 return out; 1123} 1124 1125 1126/* 1127 * If eofmark is NULL, read a word or a redirection symbol. If eofmark 1128 * is not NULL, read a here document. In the latter case, eofmark is the 1129 * word which marks the end of the document and striptabs is true if 1130 * leading tabs should be stripped from the document. The argument firstc 1131 * is the first character of the input token or document. 1132 * 1133 * Because C does not have internal subroutines, I have simulated them 1134 * using goto's to implement the subroutine linkage. The following macros 1135 * will run code that appears at the end of readtoken1. 1136 */ 1137 1138#define CHECKEND() {goto checkend; checkend_return:;} 1139#define PARSEREDIR() {goto parseredir; parseredir_return:;} 1140#define PARSESUB() {goto parsesub; parsesub_return:;} 1141#define PARSEARITH() {goto parsearith; parsearith_return:;} 1142 1143STATIC int 1144readtoken1(int firstc, char const *initialsyntax, char *eofmark, int striptabs) 1145{ 1146 int c = firstc; 1147 char *out; 1148 int len; 1149 char line[EOFMARKLEN + 1]; 1150 struct nodelist *bqlist; 1151 int quotef; 1152 int newvarnest; 1153 int level; 1154 int synentry; 1155 struct tokenstate state_static[MAXNEST_STATIC]; 1156 int maxnest = MAXNEST_STATIC; 1157 struct tokenstate *state = state_static; 1158 1159 startlinno = plinno; 1160 quotef = 0; 1161 bqlist = NULL; 1162 newvarnest = 0; 1163 level = 0; 1164 state[level].syntax = initialsyntax; 1165 state[level].parenlevel = 0; 1166 state[level].category = TSTATE_TOP; 1167 1168 STARTSTACKSTR(out); 1169 loop: { /* for each line, until end of word */ 1170 CHECKEND(); /* set c to PEOF if at end of here document */ 1171 for (;;) { /* until end of line or end of word */ 1172 CHECKSTRSPACE(3, out); /* permit 3 calls to USTPUTC */ 1173 1174 synentry = state[level].syntax[c]; 1175 1176 switch(synentry) { 1177 case CNL: /* '\n' */ 1178 if (state[level].syntax == BASESYNTAX) 1179 goto endword; /* exit outer loop */ 1180 USTPUTC(c, out); 1181 plinno++; 1182 if (doprompt) 1183 setprompt(2); 1184 else 1185 setprompt(0); 1186 c = pgetc(); 1187 goto loop; /* continue outer loop */ 1188 case CWORD: 1189 USTPUTC(c, out); 1190 break; 1191 case CCTL: 1192 if (eofmark == NULL || initialsyntax != SQSYNTAX) 1193 USTPUTC(CTLESC, out); 1194 USTPUTC(c, out); 1195 break; 1196 case CBACK: /* backslash */ 1197 c = pgetc(); 1198 if (c == PEOF) { 1199 USTPUTC('\\', out); 1200 pungetc(); 1201 } else if (c == '\n') { 1202 plinno++; 1203 if (doprompt) 1204 setprompt(2); 1205 else 1206 setprompt(0); 1207 } else { 1208 if (state[level].syntax == DQSYNTAX && 1209 c != '\\' && c != '`' && c != '$' && 1210 (c != '"' || (eofmark != NULL && 1211 newvarnest == 0)) && 1212 (c != '}' || state[level].category != TSTATE_VAR_OLD)) 1213 USTPUTC('\\', out); 1214 if (SQSYNTAX[c] == CCTL) 1215 USTPUTC(CTLESC, out); 1216 else if (eofmark == NULL || 1217 newvarnest > 0) 1218 USTPUTC(CTLQUOTEMARK, out); 1219 USTPUTC(c, out); 1220 quotef++; 1221 } 1222 break; 1223 case CSQUOTE: 1224 USTPUTC(CTLQUOTEMARK, out); 1225 state[level].syntax = SQSYNTAX; 1226 break; 1227 case CDQUOTE: 1228 USTPUTC(CTLQUOTEMARK, out); 1229 state[level].syntax = DQSYNTAX; 1230 break; 1231 case CENDQUOTE: 1232 if (eofmark != NULL && newvarnest == 0) 1233 USTPUTC(c, out); 1234 else { 1235 if (state[level].category == TSTATE_ARITH) 1236 state[level].syntax = ARISYNTAX; 1237 else 1238 state[level].syntax = BASESYNTAX; 1239 quotef++; 1240 } 1241 break; 1242 case CVAR: /* '$' */ 1243 PARSESUB(); /* parse substitution */ 1244 break; 1245 case CENDVAR: /* '}' */ 1246 if (level > 0 && 1247 (state[level].category == TSTATE_VAR_OLD || 1248 state[level].category == TSTATE_VAR_NEW)) { 1249 if (state[level].category == TSTATE_VAR_OLD) 1250 state[level - 1].syntax = state[level].syntax; 1251 else 1252 newvarnest--; 1253 level--; 1254 USTPUTC(CTLENDVAR, out); 1255 } else { 1256 USTPUTC(c, out); 1257 } 1258 break; 1259 case CLP: /* '(' in arithmetic */ 1260 state[level].parenlevel++; 1261 USTPUTC(c, out); 1262 break; 1263 case CRP: /* ')' in arithmetic */ 1264 if (state[level].parenlevel > 0) { 1265 USTPUTC(c, out); 1266 --state[level].parenlevel; 1267 } else { 1268 if (pgetc() == ')') { 1269 if (level > 0 && 1270 state[level].category == TSTATE_ARITH) { 1271 level--; 1272 USTPUTC(CTLENDARI, out); 1273 } else 1274 USTPUTC(')', out); 1275 } else { 1276 /* 1277 * unbalanced parens 1278 * (don't 2nd guess - no error) 1279 */ 1280 pungetc(); 1281 USTPUTC(')', out); 1282 } 1283 } 1284 break; 1285 case CBQUOTE: /* '`' */ 1286 out = parsebackq(out, &bqlist, 1, 1287 state[level].syntax == DQSYNTAX && 1288 (eofmark == NULL || newvarnest > 0), 1289 state[level].syntax == DQSYNTAX || state[level].syntax == ARISYNTAX); 1290 break; 1291 case CEOF: 1292 goto endword; /* exit outer loop */ 1293 default: 1294 if (level == 0) 1295 goto endword; /* exit outer loop */ 1296 USTPUTC(c, out); 1297 } 1298 c = pgetc_macro(); 1299 } 1300 } 1301endword: 1302 if (state[level].syntax == ARISYNTAX) 1303 synerror("Missing '))'"); 1304 if (state[level].syntax != BASESYNTAX && eofmark == NULL) 1305 synerror("Unterminated quoted string"); 1306 if (state[level].category == TSTATE_VAR_OLD || 1307 state[level].category == TSTATE_VAR_NEW) { 1308 startlinno = plinno; 1309 synerror("Missing '}'"); 1310 } 1311 if (state != state_static) 1312 parser_temp_free_upto(state); 1313 USTPUTC('\0', out); 1314 len = out - stackblock(); 1315 out = stackblock(); 1316 if (eofmark == NULL) { 1317 if ((c == '>' || c == '<') 1318 && quotef == 0 1319 && len <= 2 1320 && (*out == '\0' || is_digit(*out))) { 1321 PARSEREDIR(); 1322 return lasttoken = TREDIR; 1323 } else { 1324 pungetc(); 1325 } 1326 } 1327 quoteflag = quotef; 1328 backquotelist = bqlist; 1329 grabstackblock(len); 1330 wordtext = out; 1331 return lasttoken = TWORD; 1332/* end of readtoken routine */ 1333 1334 1335/* 1336 * Check to see whether we are at the end of the here document. When this 1337 * is called, c is set to the first character of the next input line. If 1338 * we are at the end of the here document, this routine sets the c to PEOF. 1339 */ 1340 1341checkend: { 1342 if (eofmark) { 1343 if (striptabs) { 1344 while (c == '\t') 1345 c = pgetc(); 1346 } 1347 if (c == *eofmark) { 1348 if (pfgets(line, sizeof line) != NULL) { 1349 char *p, *q; 1350 1351 p = line; 1352 for (q = eofmark + 1 ; *q && *p == *q ; p++, q++); 1353 if (*p == '\n' && *q == '\0') { 1354 c = PEOF; 1355 plinno++; 1356 needprompt = doprompt; 1357 } else { 1358 pushstring(line, strlen(line), NULL); 1359 } 1360 } 1361 } 1362 } 1363 goto checkend_return; 1364} 1365 1366 1367/* 1368 * Parse a redirection operator. The variable "out" points to a string 1369 * specifying the fd to be redirected. The variable "c" contains the 1370 * first character of the redirection operator. 1371 */ 1372 1373parseredir: { 1374 char fd = *out; 1375 union node *np; 1376 1377 np = (union node *)stalloc(sizeof (struct nfile)); 1378 if (c == '>') { 1379 np->nfile.fd = 1; 1380 c = pgetc(); 1381 if (c == '>') 1382 np->type = NAPPEND; 1383 else if (c == '&') 1384 np->type = NTOFD; 1385 else if (c == '|') 1386 np->type = NCLOBBER; 1387 else { 1388 np->type = NTO; 1389 pungetc(); 1390 } 1391 } else { /* c == '<' */ 1392 np->nfile.fd = 0; 1393 c = pgetc(); 1394 if (c == '<') { 1395 if (sizeof (struct nfile) != sizeof (struct nhere)) { 1396 np = (union node *)stalloc(sizeof (struct nhere)); 1397 np->nfile.fd = 0; 1398 } 1399 np->type = NHERE; 1400 heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc)); 1401 heredoc->here = np; 1402 if ((c = pgetc()) == '-') { 1403 heredoc->striptabs = 1; 1404 } else { 1405 heredoc->striptabs = 0; 1406 pungetc(); 1407 } 1408 } else if (c == '&') 1409 np->type = NFROMFD; 1410 else if (c == '>') 1411 np->type = NFROMTO; 1412 else { 1413 np->type = NFROM; 1414 pungetc(); 1415 } 1416 } 1417 if (fd != '\0') 1418 np->nfile.fd = digit_val(fd); 1419 redirnode = np; 1420 goto parseredir_return; 1421} 1422 1423 1424/* 1425 * Parse a substitution. At this point, we have read the dollar sign 1426 * and nothing else. 1427 */ 1428 1429parsesub: { 1430 char buf[10]; 1431 int subtype; 1432 int typeloc; 1433 int flags; 1434 char *p; 1435 static const char types[] = "}-+?="; 1436 int bracketed_name = 0; /* used to handle ${[0-9]*} variables */ 1437 int i; 1438 int linno; 1439 int length; 1440 1441 c = pgetc(); 1442 if (c != '(' && c != '{' && (is_eof(c) || !is_name(c)) && 1443 !is_special(c)) { 1444 USTPUTC('$', out); 1445 pungetc(); 1446 } else if (c == '(') { /* $(command) or $((arith)) */ 1447 if (pgetc() == '(') { 1448 PARSEARITH(); 1449 } else { 1450 pungetc(); 1451 out = parsebackq(out, &bqlist, 0, 1452 state[level].syntax == DQSYNTAX && 1453 (eofmark == NULL || newvarnest > 0), 1454 state[level].syntax == DQSYNTAX || 1455 state[level].syntax == ARISYNTAX); 1456 } 1457 } else { 1458 USTPUTC(CTLVAR, out); 1459 typeloc = out - stackblock(); 1460 USTPUTC(VSNORMAL, out); 1461 subtype = VSNORMAL; 1462 flags = 0; 1463 if (c == '{') { 1464 bracketed_name = 1; 1465 c = pgetc(); 1466 if (c == '#') { 1467 if ((c = pgetc()) == '}') 1468 c = '#'; 1469 else 1470 subtype = VSLENGTH; 1471 } 1472 else 1473 subtype = 0; 1474 } 1475 if (!is_eof(c) && is_name(c)) { 1476 length = 0; 1477 do { 1478 STPUTC(c, out); 1479 c = pgetc(); 1480 length++; 1481 } while (!is_eof(c) && is_in_name(c)); 1482 if (length == 6 && 1483 strncmp(out - length, "LINENO", length) == 0) { 1484 /* Replace the variable name with the 1485 * current line number. */ 1486 linno = plinno; 1487 if (funclinno != 0) 1488 linno -= funclinno - 1; 1489 snprintf(buf, sizeof(buf), "%d", linno); 1490 STADJUST(-6, out); 1491 for (i = 0; buf[i] != '\0'; i++) 1492 STPUTC(buf[i], out); 1493 flags |= VSLINENO; 1494 } 1495 } else if (is_digit(c)) { 1496 if (bracketed_name) { 1497 do { 1498 STPUTC(c, out); 1499 c = pgetc(); 1500 } while (is_digit(c)); 1501 } else { 1502 STPUTC(c, out); 1503 c = pgetc(); 1504 } 1505 } else { 1506 if (! is_special(c)) { 1507 subtype = VSERROR; 1508 if (c == '}') 1509 pungetc(); 1510 else if (c == '\n' || c == PEOF) 1511 synerror("Unexpected end of line in substitution"); 1512 else 1513 USTPUTC(c, out); 1514 } else { 1515 USTPUTC(c, out); 1516 c = pgetc(); 1517 } 1518 } 1519 if (subtype == 0) { 1520 switch (c) { 1521 case ':': 1522 flags |= VSNUL; 1523 c = pgetc(); 1524 /*FALLTHROUGH*/ 1525 default: 1526 p = strchr(types, c); 1527 if (p == NULL) { 1528 if (c == '\n' || c == PEOF) 1529 synerror("Unexpected end of line in substitution"); 1530 if (flags == VSNUL) 1531 STPUTC(':', out); 1532 STPUTC(c, out); 1533 subtype = VSERROR; 1534 } else 1535 subtype = p - types + VSNORMAL; 1536 break; 1537 case '%': 1538 case '#': 1539 { 1540 int cc = c; 1541 subtype = c == '#' ? VSTRIMLEFT : 1542 VSTRIMRIGHT; 1543 c = pgetc(); 1544 if (c == cc) 1545 subtype++; 1546 else 1547 pungetc(); 1548 break; 1549 } 1550 } 1551 } else if (subtype != VSERROR) { 1552 pungetc(); 1553 } 1554 STPUTC('=', out); 1555 if (subtype != VSLENGTH && (state[level].syntax == DQSYNTAX || 1556 state[level].syntax == ARISYNTAX)) 1557 flags |= VSQUOTE; 1558 *(stackblock() + typeloc) = subtype | flags; 1559 if (subtype != VSNORMAL) { 1560 if (level + 1 >= maxnest) { 1561 maxnest *= 2; 1562 if (state == state_static) { 1563 state = parser_temp_alloc( 1564 maxnest * sizeof(*state)); 1565 memcpy(state, state_static, 1566 MAXNEST_STATIC * sizeof(*state)); 1567 } else 1568 state = parser_temp_realloc(state, 1569 maxnest * sizeof(*state)); 1570 } 1571 level++; 1572 state[level].parenlevel = 0; 1573 if (subtype == VSMINUS || subtype == VSPLUS || 1574 subtype == VSQUESTION || subtype == VSASSIGN) { 1575 /* 1576 * For operators that were in the Bourne shell, 1577 * inherit the double-quote state. 1578 */ 1579 state[level].syntax = state[level - 1].syntax; 1580 state[level].category = TSTATE_VAR_OLD; 1581 } else { 1582 /* 1583 * The other operators take a pattern, 1584 * so go to BASESYNTAX. 1585 * Also, ' and " are now special, even 1586 * in here documents. 1587 */ 1588 state[level].syntax = BASESYNTAX; 1589 state[level].category = TSTATE_VAR_NEW; 1590 newvarnest++; 1591 } 1592 } 1593 } 1594 goto parsesub_return; 1595} 1596 1597 1598/* 1599 * Parse an arithmetic expansion (indicate start of one and set state) 1600 */ 1601parsearith: { 1602 1603 if (level + 1 >= maxnest) { 1604 maxnest *= 2; 1605 if (state == state_static) { 1606 state = parser_temp_alloc( 1607 maxnest * sizeof(*state)); 1608 memcpy(state, state_static, 1609 MAXNEST_STATIC * sizeof(*state)); 1610 } else 1611 state = parser_temp_realloc(state, 1612 maxnest * sizeof(*state)); 1613 } 1614 level++; 1615 state[level].syntax = ARISYNTAX; 1616 state[level].parenlevel = 0; 1617 state[level].category = TSTATE_ARITH; 1618 USTPUTC(CTLARI, out); 1619 if (state[level - 1].syntax == DQSYNTAX) 1620 USTPUTC('"',out); 1621 else 1622 USTPUTC(' ',out); 1623 goto parsearith_return; 1624} 1625 1626} /* end of readtoken */ 1627 1628 1629 1630#ifdef mkinit 1631RESET { 1632 tokpushback = 0; 1633 checkkwd = 0; 1634} 1635#endif 1636 1637/* 1638 * Returns true if the text contains nothing to expand (no dollar signs 1639 * or backquotes). 1640 */ 1641 1642STATIC int 1643noexpand(char *text) 1644{ 1645 char *p; 1646 char c; 1647 1648 p = text; 1649 while ((c = *p++) != '\0') { 1650 if ( c == CTLQUOTEMARK) 1651 continue; 1652 if (c == CTLESC) 1653 p++; 1654 else if (BASESYNTAX[(int)c] == CCTL) 1655 return 0; 1656 } 1657 return 1; 1658} 1659 1660 1661/* 1662 * Return true if the argument is a legal variable name (a letter or 1663 * underscore followed by zero or more letters, underscores, and digits). 1664 */ 1665 1666int 1667goodname(const char *name) 1668{ 1669 const char *p; 1670 1671 p = name; 1672 if (! is_name(*p)) 1673 return 0; 1674 while (*++p) { 1675 if (! is_in_name(*p)) 1676 return 0; 1677 } 1678 return 1; 1679} 1680 1681 1682/* 1683 * Called when an unexpected token is read during the parse. The argument 1684 * is the token that is expected, or -1 if more than one type of token can 1685 * occur at this point. 1686 */ 1687 1688STATIC void 1689synexpect(int token) 1690{ 1691 char msg[64]; 1692 1693 if (token >= 0) { 1694 fmtstr(msg, 64, "%s unexpected (expecting %s)", 1695 tokname[lasttoken], tokname[token]); 1696 } else { 1697 fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]); 1698 } 1699 synerror(msg); 1700} 1701 1702 1703STATIC void 1704synerror(const char *msg) 1705{ 1706 if (commandname) 1707 outfmt(out2, "%s: %d: ", commandname, startlinno); 1708 outfmt(out2, "Syntax error: %s\n", msg); 1709 error((char *)NULL); 1710} 1711 1712STATIC void 1713setprompt(int which) 1714{ 1715 whichprompt = which; 1716 1717#ifndef NO_HISTORY 1718 if (!el) 1719#endif 1720 { 1721 out2str(getprompt(NULL)); 1722 flushout(out2); 1723 } 1724} 1725 1726/* 1727 * called by editline -- any expansions to the prompt 1728 * should be added here. 1729 */ 1730char * 1731getprompt(void *unused __unused) 1732{ 1733 static char ps[PROMPTLEN]; 1734 char *fmt; 1735 int i, j, trim; 1736 static char internal_error[] = "<internal prompt error>"; 1737 1738 /* 1739 * Select prompt format. 1740 */ 1741 switch (whichprompt) { 1742 case 0: 1743 fmt = nullstr; 1744 break; 1745 case 1: 1746 fmt = ps1val(); 1747 break; 1748 case 2: 1749 fmt = ps2val(); 1750 break; 1751 default: 1752 return internal_error; 1753 } 1754 1755 /* 1756 * Format prompt string. 1757 */ 1758 for (i = 0; (i < 127) && (*fmt != '\0'); i++, fmt++) 1759 if (*fmt == '\\') 1760 switch (*++fmt) { 1761 1762 /* 1763 * Hostname. 1764 * 1765 * \h specifies just the local hostname, 1766 * \H specifies fully-qualified hostname. 1767 */ 1768 case 'h': 1769 case 'H': 1770 ps[i] = '\0'; 1771 gethostname(&ps[i], PROMPTLEN - i); 1772 /* Skip to end of hostname. */ 1773 trim = (*fmt == 'h') ? '.' : '\0'; 1774 while ((ps[i+1] != '\0') && (ps[i+1] != trim)) 1775 i++; 1776 break; 1777 1778 /* 1779 * Working directory. 1780 * 1781 * \W specifies just the final component, 1782 * \w specifies the entire path. 1783 */ 1784 case 'W': 1785 case 'w': 1786 ps[i] = '\0'; 1787 getcwd(&ps[i], PROMPTLEN - i); 1788 if (*fmt == 'W' && ps[i + 1] != '\0') { 1789 /* Final path component only. */ 1790 trim = 1; 1791 for (j = i; ps[j] != '\0'; j++) 1792 if (ps[j] == '/') 1793 trim = j + 1; 1794 memmove(&ps[i], &ps[trim], 1795 j - trim + 1); 1796 } 1797 /* Skip to end of path. */ 1798 while (ps[i + 1] != '\0') 1799 i++; 1800 break; 1801 1802 /* 1803 * Superuser status. 1804 * 1805 * '$' for normal users, '#' for root. 1806 */ 1807 case '$': 1808 ps[i] = (geteuid() != 0) ? '$' : '#'; 1809 break; 1810 1811 /* 1812 * A literal \. 1813 */ 1814 case '\\': 1815 ps[i] = '\\'; 1816 break; 1817 1818 /* 1819 * Emit unrecognized formats verbatim. 1820 */ 1821 default: 1822 ps[i++] = '\\'; 1823 ps[i] = *fmt; 1824 break; 1825 } 1826 else 1827 ps[i] = *fmt; 1828 ps[i] = '\0'; 1829 return (ps); 1830} 1831