1 /* $OpenBSD: lex.c,v 1.51 2015/09/10 22:48:58 nicm Exp $ */ 2 3 /*- 4 * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 5 * 2011, 2012, 2013, 2014, 2015, 2016 6 * mirabilos <m (at) mirbsd.org> 7 * 8 * Provided that these terms and disclaimer and all copyright notices 9 * are retained or reproduced in an accompanying document, permission 10 * is granted to deal in this work without restriction, including un- 11 * limited rights to use, publicly perform, distribute, sell, modify, 12 * merge, give away, or sublicence. 13 * 14 * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to 15 * the utmost extent permitted by applicable law, neither express nor 16 * implied; without malicious intent or gross negligence. In no event 17 * may a licensor, author or contributor be held liable for indirect, 18 * direct, other damage, loss, or other issues arising in any way out 19 * of dealing in the work, even if advised of the possibility of such 20 * damage or existence of a defect, except proven that it results out 21 * of said person's immediate fault when using the work as intended. 22 */ 23 24 #include "sh.h" 25 26 __RCSID("$MirOS: src/bin/mksh/lex.c,v 1.228 2016/08/01 21:38:03 tg Exp $"); 27 28 /* 29 * states while lexing word 30 */ 31 #define SBASE 0 /* outside any lexical constructs */ 32 #define SWORD 1 /* implicit quoting for substitute() */ 33 #define SLETPAREN 2 /* inside (( )), implicit quoting */ 34 #define SSQUOTE 3 /* inside '' */ 35 #define SDQUOTE 4 /* inside "" */ 36 #define SEQUOTE 5 /* inside $'' */ 37 #define SBRACE 6 /* inside ${} */ 38 #define SQBRACE 7 /* inside "${}" */ 39 #define SBQUOTE 8 /* inside `` */ 40 #define SASPAREN 9 /* inside $(( )) */ 41 #define SHEREDELIM 10 /* parsing << or <<- delimiter */ 42 #define SHEREDQUOTE 11 /* parsing " in << or <<- delimiter */ 43 #define SPATTERN 12 /* parsing *(...|...) pattern (*+?@!) */ 44 #define SADELIM 13 /* like SBASE, looking for delimiter */ 45 #define STBRACEKORN 14 /* parsing ${...[#%]...} !FSH */ 46 #define STBRACEBOURNE 15 /* parsing ${...[#%]...} FSH */ 47 #define SINVALID 255 /* invalid state */ 48 49 struct sretrace_info { 50 struct sretrace_info *next; 51 XString xs; 52 char *xp; 53 }; 54 55 /* 56 * Structure to keep track of the lexing state and the various pieces of info 57 * needed for each particular state. 58 */ 59 typedef struct lex_state { 60 union { 61 /* point to the next state block */ 62 struct lex_state *base; 63 /* marks start of state output in output string */ 64 size_t start; 65 /* SBQUOTE: true if in double quotes: "`...`" */ 66 /* SEQUOTE: got NUL, ignore rest of string */ 67 bool abool; 68 /* SADELIM information */ 69 struct { 70 /* character to search for */ 71 unsigned char delimiter; 72 /* max. number of delimiters */ 73 unsigned char num; 74 } adelim; 75 } u; 76 /* count open parentheses */ 77 short nparen; 78 /* type of this state */ 79 uint8_t type; 80 } Lex_state; 81 #define ls_base u.base 82 #define ls_start u.start 83 #define ls_bool u.abool 84 #define ls_adelim u.adelim 85 86 typedef struct { 87 Lex_state *base; 88 Lex_state *end; 89 } State_info; 90 91 static void readhere(struct ioword *); 92 static void ungetsc(int); 93 static void ungetsc_i(int); 94 static int getsc_uu(void); 95 static void getsc_line(Source *); 96 static int getsc_bn(void); 97 static int getsc_i(void); 98 static char *get_brace_var(XString *, char *); 99 static bool arraysub(char **); 100 static void gethere(void); 101 static Lex_state *push_state_i(State_info *, Lex_state *); 102 static Lex_state *pop_state_i(State_info *, Lex_state *); 103 104 static int backslash_skip; 105 static int ignore_backslash_newline; 106 107 /* optimised getsc_bn() */ 108 #define o_getsc() (*source->str != '\0' && *source->str != '\\' && \ 109 !backslash_skip ? *source->str++ : getsc_bn()) 110 /* optimised getsc_uu() */ 111 #define o_getsc_u() ((*source->str != '\0') ? *source->str++ : getsc_uu()) 112 113 /* retrace helper */ 114 #define o_getsc_r(carg) \ 115 int cev = (carg); \ 116 struct sretrace_info *rp = retrace_info; \ 117 \ 118 while (rp) { \ 119 Xcheck(rp->xs, rp->xp); \ 120 *rp->xp++ = cev; \ 121 rp = rp->next; \ 122 } \ 123 \ 124 return (cev); 125 126 /* callback */ 127 static int 128 getsc_i(void) 129 { 130 o_getsc_r(o_getsc()); 131 } 132 133 #if defined(MKSH_SMALL) && !defined(MKSH_SMALL_BUT_FAST) 134 #define getsc getsc_i 135 #else 136 static int getsc_r(int); 137 138 static int 139 getsc_r(int c) 140 { 141 o_getsc_r(c); 142 } 143 144 #define getsc() getsc_r(o_getsc()) 145 #endif 146 147 #define STATE_BSIZE 8 148 149 #define PUSH_STATE(s) do { \ 150 if (++statep == state_info.end) \ 151 statep = push_state_i(&state_info, statep); \ 152 state = statep->type = (s); \ 153 } while (/* CONSTCOND */ 0) 154 155 #define POP_STATE() do { \ 156 if (--statep == state_info.base) \ 157 statep = pop_state_i(&state_info, statep); \ 158 state = statep->type; \ 159 } while (/* CONSTCOND */ 0) 160 161 #define PUSH_SRETRACE(s) do { \ 162 struct sretrace_info *ri; \ 163 \ 164 PUSH_STATE(s); \ 165 statep->ls_start = Xsavepos(ws, wp); \ 166 ri = alloc(sizeof(struct sretrace_info), ATEMP); \ 167 Xinit(ri->xs, ri->xp, 64, ATEMP); \ 168 ri->next = retrace_info; \ 169 retrace_info = ri; \ 170 } while (/* CONSTCOND */ 0) 171 172 #define POP_SRETRACE() do { \ 173 wp = Xrestpos(ws, wp, statep->ls_start); \ 174 *retrace_info->xp = '\0'; \ 175 sp = Xstring(retrace_info->xs, retrace_info->xp); \ 176 dp = (void *)retrace_info; \ 177 retrace_info = retrace_info->next; \ 178 afree(dp, ATEMP); \ 179 POP_STATE(); \ 180 } while (/* CONSTCOND */ 0) 181 182 /** 183 * Lexical analyser 184 * 185 * tokens are not regular expressions, they are LL(1). 186 * for example, "${var:-${PWD}}", and "$(size $(whence ksh))". 187 * hence the state stack. Note "$(...)" are now parsed recursively. 188 */ 189 190 int 191 yylex(int cf) 192 { 193 Lex_state states[STATE_BSIZE], *statep, *s2, *base; 194 State_info state_info; 195 int c, c2, state; 196 size_t cz; 197 XString ws; /* expandable output word */ 198 char *wp; /* output word pointer */ 199 char *sp, *dp; 200 201 Again: 202 states[0].type = SINVALID; 203 states[0].ls_base = NULL; 204 statep = &states[1]; 205 state_info.base = states; 206 state_info.end = &state_info.base[STATE_BSIZE]; 207 208 Xinit(ws, wp, 64, ATEMP); 209 210 backslash_skip = 0; 211 ignore_backslash_newline = 0; 212 213 if (cf & ONEWORD) 214 state = SWORD; 215 else if (cf & LETEXPR) { 216 /* enclose arguments in (double) quotes */ 217 *wp++ = OQUOTE; 218 state = SLETPAREN; 219 statep->nparen = 0; 220 } else { 221 /* normal lexing */ 222 state = (cf & HEREDELIM) ? SHEREDELIM : SBASE; 223 while ((c = getsc()) == ' ' || c == '\t') 224 ; 225 if (c == '#') { 226 ignore_backslash_newline++; 227 while ((c = getsc()) != '\0' && c != '\n') 228 ; 229 ignore_backslash_newline--; 230 } 231 ungetsc(c); 232 } 233 if (source->flags & SF_ALIAS) { 234 /* trailing ' ' in alias definition */ 235 source->flags &= ~SF_ALIAS; 236 /* POSIX: trailing space only counts if parsing simple cmd */ 237 if (!Flag(FPOSIX) || (cf & CMDWORD)) 238 cf |= ALIAS; 239 } 240 241 /* Initial state: one of SWORD SLETPAREN SHEREDELIM SBASE */ 242 statep->type = state; 243 244 /* collect non-special or quoted characters to form word */ 245 while (!((c = getsc()) == 0 || 246 ((state == SBASE || state == SHEREDELIM) && ctype(c, C_LEX1)))) { 247 if (state == SBASE && 248 subshell_nesting_type == /*{*/ '}' && 249 c == /*{*/ '}') 250 /* possibly end ${ :;} */ 251 break; 252 Xcheck(ws, wp); 253 switch (state) { 254 case SADELIM: 255 if (c == '(') 256 statep->nparen++; 257 else if (c == ')') 258 statep->nparen--; 259 else if (statep->nparen == 0 && (c == /*{*/ '}' || 260 c == (int)statep->ls_adelim.delimiter)) { 261 *wp++ = ADELIM; 262 *wp++ = c; 263 if (c == /*{*/ '}' || --statep->ls_adelim.num == 0) 264 POP_STATE(); 265 if (c == /*{*/ '}') 266 POP_STATE(); 267 break; 268 } 269 /* FALLTHROUGH */ 270 case SBASE: 271 if (c == '[' && (cf & CMDASN)) { 272 /* temporary */ 273 *wp = EOS; 274 if (is_wdvarname(Xstring(ws, wp), false)) { 275 char *p, *tmp; 276 277 if (arraysub(&tmp)) { 278 *wp++ = CHAR; 279 *wp++ = c; 280 for (p = tmp; *p; ) { 281 Xcheck(ws, wp); 282 *wp++ = CHAR; 283 *wp++ = *p++; 284 } 285 afree(tmp, ATEMP); 286 break; 287 } else { 288 Source *s; 289 290 s = pushs(SREREAD, 291 source->areap); 292 s->start = s->str = 293 s->u.freeme = tmp; 294 s->next = source; 295 source = s; 296 } 297 } 298 *wp++ = CHAR; 299 *wp++ = c; 300 break; 301 } 302 /* FALLTHROUGH */ 303 Sbase1: /* includes *(...|...) pattern (*+?@!) */ 304 if (c == '*' || c == '@' || c == '+' || c == '?' || 305 c == '!') { 306 c2 = getsc(); 307 if (c2 == '(' /*)*/ ) { 308 *wp++ = OPAT; 309 *wp++ = c; 310 PUSH_STATE(SPATTERN); 311 break; 312 } 313 ungetsc(c2); 314 } 315 /* FALLTHROUGH */ 316 Sbase2: /* doesn't include *(...|...) pattern (*+?@!) */ 317 switch (c) { 318 case '\\': 319 getsc_qchar: 320 if ((c = getsc())) { 321 /* trailing \ is lost */ 322 *wp++ = QCHAR; 323 *wp++ = c; 324 } 325 break; 326 case '\'': 327 open_ssquote_unless_heredoc: 328 if ((cf & HEREDOC)) 329 goto store_char; 330 *wp++ = OQUOTE; 331 ignore_backslash_newline++; 332 PUSH_STATE(SSQUOTE); 333 break; 334 case '"': 335 open_sdquote: 336 *wp++ = OQUOTE; 337 PUSH_STATE(SDQUOTE); 338 break; 339 case '$': 340 /* 341 * processing of dollar sign belongs into 342 * Subst, except for those which can open 343 * a string: $'' and $"" 344 */ 345 subst_dollar_ex: 346 c = getsc(); 347 switch (c) { 348 case '"': 349 goto open_sdquote; 350 case '\'': 351 goto open_sequote; 352 default: 353 goto SubstS; 354 } 355 default: 356 goto Subst; 357 } 358 break; 359 360 Subst: 361 switch (c) { 362 case '\\': 363 c = getsc(); 364 switch (c) { 365 case '"': 366 if ((cf & HEREDOC)) 367 goto heredocquote; 368 /* FALLTHROUGH */ 369 case '\\': 370 case '$': case '`': 371 store_qchar: 372 *wp++ = QCHAR; 373 *wp++ = c; 374 break; 375 default: 376 heredocquote: 377 Xcheck(ws, wp); 378 if (c) { 379 /* trailing \ is lost */ 380 *wp++ = CHAR; 381 *wp++ = '\\'; 382 *wp++ = CHAR; 383 *wp++ = c; 384 } 385 break; 386 } 387 break; 388 case '$': 389 c = getsc(); 390 SubstS: 391 if (c == '(') /*)*/ { 392 c = getsc(); 393 if (c == '(') /*)*/ { 394 *wp++ = EXPRSUB; 395 PUSH_SRETRACE(SASPAREN); 396 statep->nparen = 2; 397 *retrace_info->xp++ = '('; 398 } else { 399 ungetsc(c); 400 subst_command: 401 c = COMSUB; 402 subst_command2: 403 sp = yyrecursive(c); 404 cz = strlen(sp) + 1; 405 XcheckN(ws, wp, cz); 406 *wp++ = c; 407 memcpy(wp, sp, cz); 408 wp += cz; 409 } 410 } else if (c == '{') /*}*/ { 411 if ((c = getsc()) == '|') { 412 /* 413 * non-subenvironment 414 * value substitution 415 */ 416 c = VALSUB; 417 goto subst_command2; 418 } else if (ctype(c, C_IFSWS)) { 419 /* 420 * non-subenvironment 421 * "command" substitution 422 */ 423 c = FUNSUB; 424 goto subst_command2; 425 } 426 ungetsc(c); 427 *wp++ = OSUBST; 428 *wp++ = '{'; /*}*/ 429 wp = get_brace_var(&ws, wp); 430 c = getsc(); 431 /* allow :# and :% (ksh88 compat) */ 432 if (c == ':') { 433 *wp++ = CHAR; 434 *wp++ = c; 435 c = getsc(); 436 if (c == ':') { 437 *wp++ = CHAR; 438 *wp++ = '0'; 439 *wp++ = ADELIM; 440 *wp++ = ':'; 441 PUSH_STATE(SBRACE); 442 PUSH_STATE(SADELIM); 443 statep->ls_adelim.delimiter = ':'; 444 statep->ls_adelim.num = 1; 445 statep->nparen = 0; 446 break; 447 } else if (ksh_isdigit(c) || 448 c == '('/*)*/ || c == ' ' || 449 /*XXX what else? */ 450 c == '$') { 451 /* substring subst. */ 452 if (c != ' ') { 453 *wp++ = CHAR; 454 *wp++ = ' '; 455 } 456 ungetsc(c); 457 PUSH_STATE(SBRACE); 458 PUSH_STATE(SADELIM); 459 statep->ls_adelim.delimiter = ':'; 460 statep->ls_adelim.num = 2; 461 statep->nparen = 0; 462 break; 463 } 464 } else if (c == '/') { 465 c2 = ADELIM; 466 parse_adelim_slash: 467 *wp++ = CHAR; 468 *wp++ = c; 469 if ((c = getsc()) == '/') { 470 *wp++ = c2; 471 *wp++ = c; 472 } else 473 ungetsc(c); 474 PUSH_STATE(SBRACE); 475 PUSH_STATE(SADELIM); 476 statep->ls_adelim.delimiter = '/'; 477 statep->ls_adelim.num = 1; 478 statep->nparen = 0; 479 break; 480 } else if (c == '@') { 481 c2 = getsc(); 482 ungetsc(c2); 483 if (c2 == '/') { 484 c2 = CHAR; 485 goto parse_adelim_slash; 486 } 487 } 488 /* 489 * If this is a trim operation, 490 * treat (,|,) specially in STBRACE. 491 */ 492 if (ctype(c, C_SUBOP2)) { 493 ungetsc(c); 494 if (Flag(FSH)) 495 PUSH_STATE(STBRACEBOURNE); 496 else 497 PUSH_STATE(STBRACEKORN); 498 } else { 499 ungetsc(c); 500 if (state == SDQUOTE || 501 state == SQBRACE) 502 PUSH_STATE(SQBRACE); 503 else 504 PUSH_STATE(SBRACE); 505 } 506 } else if (ksh_isalphx(c)) { 507 *wp++ = OSUBST; 508 *wp++ = 'X'; 509 do { 510 Xcheck(ws, wp); 511 *wp++ = c; 512 c = getsc(); 513 } while (ksh_isalnux(c)); 514 *wp++ = '\0'; 515 *wp++ = CSUBST; 516 *wp++ = 'X'; 517 ungetsc(c); 518 } else if (ctype(c, C_VAR1 | C_DIGIT)) { 519 Xcheck(ws, wp); 520 *wp++ = OSUBST; 521 *wp++ = 'X'; 522 *wp++ = c; 523 *wp++ = '\0'; 524 *wp++ = CSUBST; 525 *wp++ = 'X'; 526 } else { 527 *wp++ = CHAR; 528 *wp++ = '$'; 529 ungetsc(c); 530 } 531 break; 532 case '`': 533 subst_gravis: 534 PUSH_STATE(SBQUOTE); 535 *wp++ = COMSUB; 536 /* 537 * We need to know whether we are within double 538 * quotes in order to translate \" to " within 539 * "`\"`" because, unlike for COMSUBs, the 540 * outer double quoteing changes the backslash 541 * meaning for the inside. For more details: 542 * http://austingroupbugs.net/view.php?id=1015 543 */ 544 statep->ls_bool = false; 545 s2 = statep; 546 base = state_info.base; 547 while (/* CONSTCOND */ 1) { 548 for (; s2 != base; s2--) { 549 if (s2->type == SDQUOTE) { 550 statep->ls_bool = true; 551 break; 552 } 553 } 554 if (s2 != base) 555 break; 556 if (!(s2 = s2->ls_base)) 557 break; 558 base = s2-- - STATE_BSIZE; 559 } 560 break; 561 case QCHAR: 562 if (cf & LQCHAR) { 563 *wp++ = QCHAR; 564 *wp++ = getsc(); 565 break; 566 } 567 /* FALLTHROUGH */ 568 default: 569 store_char: 570 *wp++ = CHAR; 571 *wp++ = c; 572 } 573 break; 574 575 case SEQUOTE: 576 if (c == '\'') { 577 POP_STATE(); 578 *wp++ = CQUOTE; 579 ignore_backslash_newline--; 580 } else if (c == '\\') { 581 if ((c2 = unbksl(true, getsc_i, ungetsc)) == -1) 582 c2 = getsc(); 583 if (c2 == 0) 584 statep->ls_bool = true; 585 if (!statep->ls_bool) { 586 char ts[4]; 587 588 if ((unsigned int)c2 < 0x100) { 589 *wp++ = QCHAR; 590 *wp++ = c2; 591 } else { 592 cz = utf_wctomb(ts, c2 - 0x100); 593 ts[cz] = 0; 594 cz = 0; 595 do { 596 *wp++ = QCHAR; 597 *wp++ = ts[cz]; 598 } while (ts[++cz]); 599 } 600 } 601 } else if (!statep->ls_bool) { 602 *wp++ = QCHAR; 603 *wp++ = c; 604 } 605 break; 606 607 case SSQUOTE: 608 if (c == '\'') { 609 POP_STATE(); 610 if ((cf & HEREDOC) || state == SQBRACE) 611 goto store_char; 612 *wp++ = CQUOTE; 613 ignore_backslash_newline--; 614 } else { 615 *wp++ = QCHAR; 616 *wp++ = c; 617 } 618 break; 619 620 case SDQUOTE: 621 if (c == '"') { 622 POP_STATE(); 623 *wp++ = CQUOTE; 624 } else 625 goto Subst; 626 break; 627 628 /* $(( ... )) */ 629 case SASPAREN: 630 if (c == '(') 631 statep->nparen++; 632 else if (c == ')') { 633 statep->nparen--; 634 if (statep->nparen == 1) { 635 /* end of EXPRSUB */ 636 POP_SRETRACE(); 637 638 if ((c2 = getsc()) == /*(*/ ')') { 639 cz = strlen(sp) - 2; 640 XcheckN(ws, wp, cz); 641 memcpy(wp, sp + 1, cz); 642 wp += cz; 643 afree(sp, ATEMP); 644 *wp++ = '\0'; 645 break; 646 } else { 647 Source *s; 648 649 ungetsc(c2); 650 /* 651 * mismatched parenthesis - 652 * assume we were really 653 * parsing a $(...) expression 654 */ 655 --wp; 656 s = pushs(SREREAD, 657 source->areap); 658 s->start = s->str = 659 s->u.freeme = sp; 660 s->next = source; 661 source = s; 662 goto subst_command; 663 } 664 } 665 } 666 /* reuse existing state machine */ 667 goto Sbase2; 668 669 case SQBRACE: 670 if (c == '\\') { 671 /* 672 * perform POSIX "quote removal" if the back- 673 * slash is "special", i.e. same cases as the 674 * {case '\\':} in Subst: plus closing brace; 675 * in mksh code "quote removal" on '\c' means 676 * write QCHAR+c, otherwise CHAR+\+CHAR+c are 677 * emitted (in heredocquote:) 678 */ 679 if ((c = getsc()) == '"' || c == '\\' || 680 c == '$' || c == '`' || c == /*{*/'}') 681 goto store_qchar; 682 goto heredocquote; 683 } 684 goto common_SQBRACE; 685 686 case SBRACE: 687 if (c == '\'') 688 goto open_ssquote_unless_heredoc; 689 else if (c == '\\') 690 goto getsc_qchar; 691 common_SQBRACE: 692 if (c == '"') 693 goto open_sdquote; 694 else if (c == '$') 695 goto subst_dollar_ex; 696 else if (c == '`') 697 goto subst_gravis; 698 else if (c != /*{*/ '}') 699 goto store_char; 700 POP_STATE(); 701 *wp++ = CSUBST; 702 *wp++ = /*{*/ '}'; 703 break; 704 705 /* Same as SBASE, except (,|,) treated specially */ 706 case STBRACEKORN: 707 if (c == '|') 708 *wp++ = SPAT; 709 else if (c == '(') { 710 *wp++ = OPAT; 711 /* simile for @ */ 712 *wp++ = ' '; 713 PUSH_STATE(SPATTERN); 714 } else /* FALLTHROUGH */ 715 case STBRACEBOURNE: 716 if (c == /*{*/ '}') { 717 POP_STATE(); 718 *wp++ = CSUBST; 719 *wp++ = /*{*/ '}'; 720 } else 721 goto Sbase1; 722 break; 723 724 case SBQUOTE: 725 if (c == '`') { 726 *wp++ = 0; 727 POP_STATE(); 728 } else if (c == '\\') { 729 switch (c = getsc()) { 730 case 0: 731 /* trailing \ is lost */ 732 break; 733 case '$': 734 case '`': 735 case '\\': 736 *wp++ = c; 737 break; 738 case '"': 739 if (statep->ls_bool) { 740 *wp++ = c; 741 break; 742 } 743 /* FALLTHROUGH */ 744 default: 745 *wp++ = '\\'; 746 *wp++ = c; 747 break; 748 } 749 } else 750 *wp++ = c; 751 break; 752 753 /* ONEWORD */ 754 case SWORD: 755 goto Subst; 756 757 /* LETEXPR: (( ... )) */ 758 case SLETPAREN: 759 if (c == /*(*/ ')') { 760 if (statep->nparen > 0) 761 --statep->nparen; 762 else if ((c2 = getsc()) == /*(*/ ')') { 763 c = 0; 764 *wp++ = CQUOTE; 765 goto Done; 766 } else { 767 Source *s; 768 769 ungetsc(c2); 770 ungetsc(c); 771 /* 772 * mismatched parenthesis - 773 * assume we were really 774 * parsing a (...) expression 775 */ 776 *wp = EOS; 777 sp = Xstring(ws, wp); 778 dp = wdstrip(sp + 1, WDS_TPUTS); 779 s = pushs(SREREAD, source->areap); 780 s->start = s->str = s->u.freeme = dp; 781 s->next = source; 782 source = s; 783 ungetsc('('/*)*/); 784 return ('('/*)*/); 785 } 786 } else if (c == '(') 787 /* 788 * parentheses inside quotes and 789 * backslashes are lost, but AT&T ksh 790 * doesn't count them either 791 */ 792 ++statep->nparen; 793 goto Sbase2; 794 795 /* << or <<- delimiter */ 796 case SHEREDELIM: 797 /* 798 * here delimiters need a special case since 799 * $ and `...` are not to be treated specially 800 */ 801 switch (c) { 802 case '\\': 803 if ((c = getsc())) { 804 /* trailing \ is lost */ 805 *wp++ = QCHAR; 806 *wp++ = c; 807 } 808 break; 809 case '\'': 810 goto open_ssquote_unless_heredoc; 811 case '$': 812 if ((c2 = getsc()) == '\'') { 813 open_sequote: 814 *wp++ = OQUOTE; 815 ignore_backslash_newline++; 816 PUSH_STATE(SEQUOTE); 817 statep->ls_bool = false; 818 break; 819 } else if (c2 == '"') { 820 /* FALLTHROUGH */ 821 case '"': 822 PUSH_SRETRACE(SHEREDQUOTE); 823 break; 824 } 825 ungetsc(c2); 826 /* FALLTHROUGH */ 827 default: 828 *wp++ = CHAR; 829 *wp++ = c; 830 } 831 break; 832 833 /* " in << or <<- delimiter */ 834 case SHEREDQUOTE: 835 if (c != '"') 836 goto Subst; 837 POP_SRETRACE(); 838 dp = strnul(sp) - 1; 839 /* remove the trailing double quote */ 840 *dp = '\0'; 841 /* store the quoted string */ 842 *wp++ = OQUOTE; 843 XcheckN(ws, wp, (dp - sp) * 2); 844 dp = sp; 845 while ((c = *dp++)) { 846 if (c == '\\') { 847 switch ((c = *dp++)) { 848 case '\\': 849 case '"': 850 case '$': 851 case '`': 852 break; 853 default: 854 *wp++ = CHAR; 855 *wp++ = '\\'; 856 break; 857 } 858 } 859 *wp++ = CHAR; 860 *wp++ = c; 861 } 862 afree(sp, ATEMP); 863 *wp++ = CQUOTE; 864 state = statep->type = SHEREDELIM; 865 break; 866 867 /* in *(...|...) pattern (*+?@!) */ 868 case SPATTERN: 869 if (c == /*(*/ ')') { 870 *wp++ = CPAT; 871 POP_STATE(); 872 } else if (c == '|') { 873 *wp++ = SPAT; 874 } else if (c == '(') { 875 *wp++ = OPAT; 876 /* simile for @ */ 877 *wp++ = ' '; 878 PUSH_STATE(SPATTERN); 879 } else 880 goto Sbase1; 881 break; 882 } 883 } 884 Done: 885 Xcheck(ws, wp); 886 if (statep != &states[1]) 887 /* XXX figure out what is missing */ 888 yyerror("no closing quote\n"); 889 890 /* This done to avoid tests for SHEREDELIM wherever SBASE tested */ 891 if (state == SHEREDELIM) 892 state = SBASE; 893 894 dp = Xstring(ws, wp); 895 if (state == SBASE && ( 896 #ifndef MKSH_LEGACY_MODE 897 (c == '&' && !Flag(FSH) && !Flag(FPOSIX)) || 898 #endif 899 c == '<' || c == '>') && ((c2 = Xlength(ws, wp)) == 0 || 900 (c2 == 2 && dp[0] == CHAR && ksh_isdigit(dp[1])))) { 901 struct ioword *iop = alloc(sizeof(struct ioword), ATEMP); 902 903 iop->unit = c2 == 2 ? ksh_numdig(dp[1]) : c == '<' ? 0 : 1; 904 905 if (c == '&') { 906 if ((c2 = getsc()) != '>') { 907 ungetsc(c2); 908 goto no_iop; 909 } 910 c = c2; 911 iop->ioflag = IOBASH; 912 } else 913 iop->ioflag = 0; 914 915 c2 = getsc(); 916 /* <<, >>, <> are ok, >< is not */ 917 if (c == c2 || (c == '<' && c2 == '>')) { 918 iop->ioflag |= c == c2 ? 919 (c == '>' ? IOCAT : IOHERE) : IORDWR; 920 if (iop->ioflag == IOHERE) { 921 if ((c2 = getsc()) == '-') 922 iop->ioflag |= IOSKIP; 923 else if (c2 == '<') 924 iop->ioflag |= IOHERESTR; 925 else 926 ungetsc(c2); 927 } 928 } else if (c2 == '&') 929 iop->ioflag |= IODUP | (c == '<' ? IORDUP : 0); 930 else { 931 iop->ioflag |= c == '>' ? IOWRITE : IOREAD; 932 if (c == '>' && c2 == '|') 933 iop->ioflag |= IOCLOB; 934 else 935 ungetsc(c2); 936 } 937 938 iop->ioname = NULL; 939 iop->delim = NULL; 940 iop->heredoc = NULL; 941 /* free word */ 942 Xfree(ws, wp); 943 yylval.iop = iop; 944 return (REDIR); 945 no_iop: 946 afree(iop, ATEMP); 947 } 948 949 if (wp == dp && state == SBASE) { 950 /* free word */ 951 Xfree(ws, wp); 952 /* no word, process LEX1 character */ 953 if ((c == '|') || (c == '&') || (c == ';') || (c == '('/*)*/)) { 954 if ((c2 = getsc()) == c) 955 c = (c == ';') ? BREAK : 956 (c == '|') ? LOGOR : 957 (c == '&') ? LOGAND : 958 /* c == '(' ) */ MDPAREN; 959 else if (c == '|' && c2 == '&') 960 c = COPROC; 961 else if (c == ';' && c2 == '|') 962 c = BRKEV; 963 else if (c == ';' && c2 == '&') 964 c = BRKFT; 965 else 966 ungetsc(c2); 967 #ifndef MKSH_SMALL 968 if (c == BREAK) { 969 if ((c2 = getsc()) == '&') 970 c = BRKEV; 971 else 972 ungetsc(c2); 973 } 974 #endif 975 } else if (c == '\n') { 976 if (cf & HEREDELIM) 977 ungetsc(c); 978 else { 979 gethere(); 980 if (cf & CONTIN) 981 goto Again; 982 } 983 } else if (c == '\0' && !(cf & HEREDELIM)) { 984 struct ioword **p = heres; 985 986 while (p < herep) 987 if ((*p)->ioflag & IOHERESTR) 988 ++p; 989 else 990 /* ksh -c 'cat <<EOF' can cause this */ 991 yyerror(Tf_heredoc, 992 evalstr((*p)->delim, 0)); 993 } 994 return (c); 995 } 996 997 /* terminate word */ 998 *wp++ = EOS; 999 yylval.cp = Xclose(ws, wp); 1000 if (state == SWORD || state == SLETPAREN 1001 /* XXX ONEWORD? */) 1002 return (LWORD); 1003 1004 /* unget terminator */ 1005 ungetsc(c); 1006 1007 /* 1008 * note: the alias-vs-function code below depends on several 1009 * interna: starting from here, source->str is not modified; 1010 * the way getsc() and ungetsc() operate; etc. 1011 */ 1012 1013 /* copy word to unprefixed string ident */ 1014 sp = yylval.cp; 1015 dp = ident; 1016 while ((dp - ident) < IDENT && (c = *sp++) == CHAR) 1017 *dp++ = *sp++; 1018 if (c != EOS) 1019 /* word is not unquoted */ 1020 dp = ident; 1021 /* make sure the ident array stays NUL padded */ 1022 memset(dp, 0, (ident + IDENT) - dp + 1); 1023 1024 if (!(cf & (KEYWORD | ALIAS))) 1025 return (LWORD); 1026 1027 if (*ident != '\0') { 1028 struct tbl *p; 1029 uint32_t h = hash(ident); 1030 1031 if ((cf & KEYWORD) && (p = ktsearch(&keywords, ident, h)) && 1032 (!(cf & ESACONLY) || p->val.i == ESAC || 1033 p->val.i == /*{*/ '}')) { 1034 afree(yylval.cp, ATEMP); 1035 return (p->val.i); 1036 } 1037 if ((cf & ALIAS) && (p = ktsearch(&aliases, ident, h)) && 1038 (p->flag & ISSET)) { 1039 /* 1040 * this still points to the same character as the 1041 * ungetsc'd terminator from above 1042 */ 1043 const char *cp = source->str; 1044 1045 /* prefer POSIX but not Korn functions over aliases */ 1046 while (*cp == ' ' || *cp == '\t') 1047 /* 1048 * this is like getsc() without skipping 1049 * over Source boundaries (including not 1050 * parsing ungetsc'd characters that got 1051 * pushed into an SREREAD) which is what 1052 * we want here anyway: find out whether 1053 * the alias name is followed by a POSIX 1054 * function definition 1055 */ 1056 ++cp; 1057 /* prefer functions over aliases */ 1058 if (cp[0] != '(' || cp[1] != ')') { 1059 Source *s = source; 1060 1061 while (s && (s->flags & SF_HASALIAS)) 1062 if (s->u.tblp == p) 1063 return (LWORD); 1064 else 1065 s = s->next; 1066 /* push alias expansion */ 1067 s = pushs(SALIAS, source->areap); 1068 s->start = s->str = p->val.s; 1069 s->u.tblp = p; 1070 s->flags |= SF_HASALIAS; 1071 s->next = source; 1072 if (source->type == SEOF) { 1073 /* prevent infinite recursion at EOS */ 1074 source->u.tblp = p; 1075 source->flags |= SF_HASALIAS; 1076 } 1077 source = s; 1078 afree(yylval.cp, ATEMP); 1079 goto Again; 1080 } 1081 } 1082 } else if (cf & ALIAS) { 1083 /* retain typeset et al. even when quoted */ 1084 if (assign_command((dp = wdstrip(yylval.cp, 0)), true)) 1085 strlcpy(ident, dp, sizeof(ident)); 1086 afree(dp, ATEMP); 1087 } 1088 1089 return (LWORD); 1090 } 1091 1092 static void 1093 gethere(void) 1094 { 1095 struct ioword **p; 1096 1097 for (p = heres; p < herep; p++) 1098 if (!((*p)->ioflag & IOHERESTR)) 1099 readhere(*p); 1100 herep = heres; 1101 } 1102 1103 /* 1104 * read "<<word" text into temp file 1105 */ 1106 1107 static void 1108 readhere(struct ioword *iop) 1109 { 1110 int c; 1111 const char *eof, *eofp; 1112 XString xs; 1113 char *xp; 1114 size_t xpos; 1115 1116 eof = evalstr(iop->delim, 0); 1117 1118 if (!(iop->ioflag & IOEVAL)) 1119 ignore_backslash_newline++; 1120 1121 Xinit(xs, xp, 256, ATEMP); 1122 1123 heredoc_read_line: 1124 /* beginning of line */ 1125 eofp = eof; 1126 xpos = Xsavepos(xs, xp); 1127 if (iop->ioflag & IOSKIP) { 1128 /* skip over leading tabs */ 1129 while ((c = getsc()) == '\t') 1130 ; /* nothing */ 1131 goto heredoc_parse_char; 1132 } 1133 heredoc_read_char: 1134 c = getsc(); 1135 heredoc_parse_char: 1136 /* compare with here document marker */ 1137 if (!*eofp) { 1138 /* end of here document marker, what to do? */ 1139 switch (c) { 1140 case /*(*/ ')': 1141 if (!subshell_nesting_type) 1142 /*- 1143 * not allowed outside $(...) or (...) 1144 * => mismatch 1145 */ 1146 break; 1147 /* allow $(...) or (...) to close here */ 1148 ungetsc(/*(*/ ')'); 1149 /* FALLTHROUGH */ 1150 case 0: 1151 /* 1152 * Allow EOF here to commands without trailing 1153 * newlines (mksh -c '...') will work as well. 1154 */ 1155 case '\n': 1156 /* Newline terminates here document marker */ 1157 goto heredoc_found_terminator; 1158 } 1159 } else if (c == *eofp++) 1160 /* store; then read and compare next character */ 1161 goto heredoc_store_and_loop; 1162 /* nope, mismatch; read until end of line */ 1163 while (c != '\n') { 1164 if (!c) 1165 /* oops, reached EOF */ 1166 yyerror(Tf_heredoc, eof); 1167 /* store character */ 1168 Xcheck(xs, xp); 1169 Xput(xs, xp, c); 1170 /* read next character */ 1171 c = getsc(); 1172 } 1173 /* we read a newline as last character */ 1174 heredoc_store_and_loop: 1175 /* store character */ 1176 Xcheck(xs, xp); 1177 Xput(xs, xp, c); 1178 if (c == '\n') 1179 goto heredoc_read_line; 1180 goto heredoc_read_char; 1181 1182 heredoc_found_terminator: 1183 /* jump back to saved beginning of line */ 1184 xp = Xrestpos(xs, xp, xpos); 1185 /* terminate, close and store */ 1186 Xput(xs, xp, '\0'); 1187 iop->heredoc = Xclose(xs, xp); 1188 1189 if (!(iop->ioflag & IOEVAL)) 1190 ignore_backslash_newline--; 1191 } 1192 1193 void 1194 yyerror(const char *fmt, ...) 1195 { 1196 va_list va; 1197 1198 /* pop aliases and re-reads */ 1199 while (source->type == SALIAS || source->type == SREREAD) 1200 source = source->next; 1201 /* zap pending input */ 1202 source->str = null; 1203 1204 error_prefix(true); 1205 va_start(va, fmt); 1206 shf_vfprintf(shl_out, fmt, va); 1207 va_end(va); 1208 errorfz(); 1209 } 1210 1211 /* 1212 * input for yylex with alias expansion 1213 */ 1214 1215 Source * 1216 pushs(int type, Area *areap) 1217 { 1218 Source *s; 1219 1220 s = alloc(sizeof(Source), areap); 1221 memset(s, 0, sizeof(Source)); 1222 s->type = type; 1223 s->str = null; 1224 s->areap = areap; 1225 if (type == SFILE || type == SSTDIN) 1226 XinitN(s->xs, 256, s->areap); 1227 return (s); 1228 } 1229 1230 static int 1231 getsc_uu(void) 1232 { 1233 Source *s = source; 1234 int c; 1235 1236 while ((c = *s->str++) == 0) { 1237 /* return 0 for EOF by default */ 1238 s->str = NULL; 1239 switch (s->type) { 1240 case SEOF: 1241 s->str = null; 1242 return (0); 1243 1244 case SSTDIN: 1245 case SFILE: 1246 getsc_line(s); 1247 break; 1248 1249 case SWSTR: 1250 break; 1251 1252 case SSTRING: 1253 case SSTRINGCMDLINE: 1254 break; 1255 1256 case SWORDS: 1257 s->start = s->str = *s->u.strv++; 1258 s->type = SWORDSEP; 1259 break; 1260 1261 case SWORDSEP: 1262 if (*s->u.strv == NULL) { 1263 s->start = s->str = "\n"; 1264 s->type = SEOF; 1265 } else { 1266 s->start = s->str = T1space; 1267 s->type = SWORDS; 1268 } 1269 break; 1270 1271 case SALIAS: 1272 if (s->flags & SF_ALIASEND) { 1273 /* pass on an unused SF_ALIAS flag */ 1274 source = s->next; 1275 source->flags |= s->flags & SF_ALIAS; 1276 s = source; 1277 } else if (*s->u.tblp->val.s && 1278 (c = strnul(s->u.tblp->val.s)[-1], ksh_isspace(c))) { 1279 /* pop source stack */ 1280 source = s = s->next; 1281 /* 1282 * Note that this alias ended with a 1283 * space, enabling alias expansion on 1284 * the following word. 1285 */ 1286 s->flags |= SF_ALIAS; 1287 } else { 1288 /* 1289 * At this point, we need to keep the current 1290 * alias in the source list so recursive 1291 * aliases can be detected and we also need to 1292 * return the next character. Do this by 1293 * temporarily popping the alias to get the 1294 * next character and then put it back in the 1295 * source list with the SF_ALIASEND flag set. 1296 */ 1297 /* pop source stack */ 1298 source = s->next; 1299 source->flags |= s->flags & SF_ALIAS; 1300 c = getsc_uu(); 1301 if (c) { 1302 s->flags |= SF_ALIASEND; 1303 s->ugbuf[0] = c; s->ugbuf[1] = '\0'; 1304 s->start = s->str = s->ugbuf; 1305 s->next = source; 1306 source = s; 1307 } else { 1308 s = source; 1309 /* avoid reading EOF twice */ 1310 s->str = NULL; 1311 break; 1312 } 1313 } 1314 continue; 1315 1316 case SREREAD: 1317 if (s->start != s->ugbuf) 1318 /* yuck */ 1319 afree(s->u.freeme, ATEMP); 1320 source = s = s->next; 1321 continue; 1322 } 1323 if (s->str == NULL) { 1324 s->type = SEOF; 1325 s->start = s->str = null; 1326 return ('\0'); 1327 } 1328 if (s->flags & SF_ECHO) { 1329 shf_puts(s->str, shl_out); 1330 shf_flush(shl_out); 1331 } 1332 } 1333 return (c); 1334 } 1335 1336 static void 1337 getsc_line(Source *s) 1338 { 1339 char *xp = Xstring(s->xs, xp), *cp; 1340 bool interactive = Flag(FTALKING) && s->type == SSTDIN; 1341 bool have_tty = tobool(interactive && (s->flags & SF_TTY)); 1342 1343 /* Done here to ensure nothing odd happens when a timeout occurs */ 1344 XcheckN(s->xs, xp, LINE); 1345 *xp = '\0'; 1346 s->start = s->str = xp; 1347 1348 if (have_tty && ksh_tmout) { 1349 ksh_tmout_state = TMOUT_READING; 1350 alarm(ksh_tmout); 1351 } 1352 if (interactive) { 1353 if (cur_prompt == PS1) 1354 histsave(&s->line, NULL, HIST_FLUSH, true); 1355 change_winsz(); 1356 } 1357 #ifndef MKSH_NO_CMDLINE_EDITING 1358 if (have_tty && ( 1359 #if !MKSH_S_NOVI 1360 Flag(FVI) || 1361 #endif 1362 Flag(FEMACS) || Flag(FGMACS))) { 1363 int nread; 1364 1365 nread = x_read(xp); 1366 if (nread < 0) 1367 /* read error */ 1368 nread = 0; 1369 xp[nread] = '\0'; 1370 xp += nread; 1371 } else 1372 #endif 1373 { 1374 if (interactive) 1375 pprompt(prompt, 0); 1376 else 1377 s->line++; 1378 1379 while (/* CONSTCOND */ 1) { 1380 char *p = shf_getse(xp, Xnleft(s->xs, xp), s->u.shf); 1381 1382 if (!p && shf_error(s->u.shf) && 1383 shf_errno(s->u.shf) == EINTR) { 1384 shf_clearerr(s->u.shf); 1385 if (trap) 1386 runtraps(0); 1387 continue; 1388 } 1389 if (!p || (xp = p, xp[-1] == '\n')) 1390 break; 1391 /* double buffer size */ 1392 /* move past NUL so doubling works... */ 1393 xp++; 1394 XcheckN(s->xs, xp, Xlength(s->xs, xp)); 1395 /* ...and move back again */ 1396 xp--; 1397 } 1398 /* 1399 * flush any unwanted input so other programs/builtins 1400 * can read it. Not very optimal, but less error prone 1401 * than flushing else where, dealing with redirections, 1402 * etc. 1403 * TODO: reduce size of shf buffer (~128?) if SSTDIN 1404 */ 1405 if (s->type == SSTDIN) 1406 shf_flush(s->u.shf); 1407 } 1408 /* 1409 * XXX: temporary kludge to restore source after a 1410 * trap may have been executed. 1411 */ 1412 source = s; 1413 if (have_tty && ksh_tmout) { 1414 ksh_tmout_state = TMOUT_EXECUTING; 1415 alarm(0); 1416 } 1417 cp = Xstring(s->xs, xp); 1418 rndpush(cp); 1419 s->start = s->str = cp; 1420 strip_nuls(Xstring(s->xs, xp), Xlength(s->xs, xp)); 1421 /* Note: if input is all nulls, this is not eof */ 1422 if (Xlength(s->xs, xp) == 0) { 1423 /* EOF */ 1424 if (s->type == SFILE) 1425 shf_fdclose(s->u.shf); 1426 s->str = NULL; 1427 } else if (interactive && *s->str) { 1428 if (cur_prompt != PS1) 1429 histsave(&s->line, s->str, HIST_APPEND, true); 1430 else if (!ctype(*s->str, C_IFS | C_IFSWS)) 1431 histsave(&s->line, s->str, HIST_QUEUE, true); 1432 #if !defined(MKSH_SMALL) && HAVE_PERSISTENT_HISTORY 1433 else 1434 goto check_for_sole_return; 1435 } else if (interactive && cur_prompt == PS1) { 1436 check_for_sole_return: 1437 cp = Xstring(s->xs, xp); 1438 while (*cp && ctype(*cp, C_IFSWS)) 1439 ++cp; 1440 if (!*cp) { 1441 histsave(&s->line, NULL, HIST_FLUSH, true); 1442 histsync(); 1443 } 1444 #endif 1445 } 1446 if (interactive) 1447 set_prompt(PS2, NULL); 1448 } 1449 1450 void 1451 set_prompt(int to, Source *s) 1452 { 1453 cur_prompt = (uint8_t)to; 1454 1455 switch (to) { 1456 /* command */ 1457 case PS1: 1458 /* 1459 * Substitute ! and !! here, before substitutions are done 1460 * so ! in expanded variables are not expanded. 1461 * NOTE: this is not what AT&T ksh does (it does it after 1462 * substitutions, POSIX doesn't say which is to be done. 1463 */ 1464 { 1465 struct shf *shf; 1466 char * volatile ps1; 1467 Area *saved_atemp; 1468 int saved_lineno; 1469 1470 ps1 = str_val(global("PS1")); 1471 shf = shf_sopen(NULL, strlen(ps1) * 2, 1472 SHF_WR | SHF_DYNAMIC, NULL); 1473 while (*ps1) 1474 if (*ps1 != '!' || *++ps1 == '!') 1475 shf_putchar(*ps1++, shf); 1476 else 1477 shf_fprintf(shf, Tf_lu, s ? 1478 (unsigned long)s->line + 1 : 0UL); 1479 ps1 = shf_sclose(shf); 1480 saved_lineno = current_lineno; 1481 if (s) 1482 current_lineno = s->line + 1; 1483 saved_atemp = ATEMP; 1484 newenv(E_ERRH); 1485 if (kshsetjmp(e->jbuf)) { 1486 prompt = safe_prompt; 1487 /* 1488 * Don't print an error - assume it has already 1489 * been printed. Reason is we may have forked 1490 * to run a command and the child may be 1491 * unwinding its stack through this code as it 1492 * exits. 1493 */ 1494 } else { 1495 char *cp = substitute(ps1, 0); 1496 strdupx(prompt, cp, saved_atemp); 1497 } 1498 current_lineno = saved_lineno; 1499 quitenv(NULL); 1500 } 1501 break; 1502 /* command continuation */ 1503 case PS2: 1504 prompt = str_val(global("PS2")); 1505 break; 1506 } 1507 } 1508 1509 int 1510 pprompt(const char *cp, int ntruncate) 1511 { 1512 char delimiter = 0; 1513 bool doprint = (ntruncate != -1); 1514 bool indelimit = false; 1515 int columns = 0, lines = 0; 1516 1517 /* 1518 * Undocumented AT&T ksh feature: 1519 * If the second char in the prompt string is \r then the first 1520 * char is taken to be a non-printing delimiter and any chars 1521 * between two instances of the delimiter are not considered to 1522 * be part of the prompt length 1523 */ 1524 if (*cp && cp[1] == '\r') { 1525 delimiter = *cp; 1526 cp += 2; 1527 } 1528 for (; *cp; cp++) { 1529 if (indelimit && *cp != delimiter) 1530 ; 1531 else if (*cp == '\n' || *cp == '\r') { 1532 lines += columns / x_cols + ((*cp == '\n') ? 1 : 0); 1533 columns = 0; 1534 } else if (*cp == '\t') { 1535 columns = (columns | 7) + 1; 1536 } else if (*cp == '\b') { 1537 if (columns > 0) 1538 columns--; 1539 } else if (*cp == delimiter) 1540 indelimit = !indelimit; 1541 else if (UTFMODE && ((unsigned char)*cp > 0x7F)) { 1542 const char *cp2; 1543 columns += utf_widthadj(cp, &cp2); 1544 if (doprint && (indelimit || 1545 (ntruncate < (x_cols * lines + columns)))) 1546 shf_write(cp, cp2 - cp, shl_out); 1547 cp = cp2 - /* loop increment */ 1; 1548 continue; 1549 } else 1550 columns++; 1551 if (doprint && (*cp != delimiter) && 1552 (indelimit || (ntruncate < (x_cols * lines + columns)))) 1553 shf_putc(*cp, shl_out); 1554 } 1555 if (doprint) 1556 shf_flush(shl_out); 1557 return (x_cols * lines + columns); 1558 } 1559 1560 /* 1561 * Read the variable part of a ${...} expression (i.e. up to but not 1562 * including the :[-+?=#%] or close-brace). 1563 */ 1564 static char * 1565 get_brace_var(XString *wsp, char *wp) 1566 { 1567 char c; 1568 enum parse_state { 1569 PS_INITIAL, PS_SAW_PERCENT, PS_SAW_HASH, PS_SAW_BANG, 1570 PS_IDENT, PS_NUMBER, PS_VAR1 1571 } state = PS_INITIAL; 1572 1573 while (/* CONSTCOND */ 1) { 1574 c = getsc(); 1575 /* State machine to figure out where the variable part ends. */ 1576 switch (state) { 1577 case PS_SAW_HASH: 1578 if (ctype(c, C_VAR1)) { 1579 char c2; 1580 1581 c2 = getsc(); 1582 ungetsc(c2); 1583 if (c2 != /*{*/ '}') { 1584 ungetsc(c); 1585 goto out; 1586 } 1587 } 1588 goto ps_common; 1589 case PS_SAW_BANG: 1590 switch (c) { 1591 case '@': 1592 case '#': 1593 case '-': 1594 case '?': 1595 goto out; 1596 } 1597 goto ps_common; 1598 case PS_INITIAL: 1599 switch (c) { 1600 case '%': 1601 state = PS_SAW_PERCENT; 1602 goto next; 1603 case '#': 1604 state = PS_SAW_HASH; 1605 goto next; 1606 case '!': 1607 state = PS_SAW_BANG; 1608 goto next; 1609 } 1610 /* FALLTHROUGH */ 1611 case PS_SAW_PERCENT: 1612 ps_common: 1613 if (ksh_isalphx(c)) 1614 state = PS_IDENT; 1615 else if (ksh_isdigit(c)) 1616 state = PS_NUMBER; 1617 else if (ctype(c, C_VAR1)) 1618 state = PS_VAR1; 1619 else 1620 goto out; 1621 break; 1622 case PS_IDENT: 1623 if (!ksh_isalnux(c)) { 1624 if (c == '[') { 1625 char *tmp, *p; 1626 1627 if (!arraysub(&tmp)) 1628 yyerror("missing ]\n"); 1629 *wp++ = c; 1630 for (p = tmp; *p; ) { 1631 Xcheck(*wsp, wp); 1632 *wp++ = *p++; 1633 } 1634 afree(tmp, ATEMP); 1635 /* the ] */ 1636 c = getsc(); 1637 } 1638 goto out; 1639 } 1640 next: 1641 break; 1642 case PS_NUMBER: 1643 if (!ksh_isdigit(c)) 1644 goto out; 1645 break; 1646 case PS_VAR1: 1647 goto out; 1648 } 1649 Xcheck(*wsp, wp); 1650 *wp++ = c; 1651 } 1652 out: 1653 /* end of variable part */ 1654 *wp++ = '\0'; 1655 ungetsc(c); 1656 return (wp); 1657 } 1658 1659 /* 1660 * Save an array subscript - returns true if matching bracket found, false 1661 * if eof or newline was found. 1662 * (Returned string double null terminated) 1663 */ 1664 static bool 1665 arraysub(char **strp) 1666 { 1667 XString ws; 1668 char *wp, c; 1669 /* we are just past the initial [ */ 1670 unsigned int depth = 1; 1671 1672 Xinit(ws, wp, 32, ATEMP); 1673 1674 do { 1675 c = getsc(); 1676 Xcheck(ws, wp); 1677 *wp++ = c; 1678 if (c == '[') 1679 depth++; 1680 else if (c == ']') 1681 depth--; 1682 } while (depth > 0 && c && c != '\n'); 1683 1684 *wp++ = '\0'; 1685 *strp = Xclose(ws, wp); 1686 1687 return (tobool(depth == 0)); 1688 } 1689 1690 /* Unget a char: handles case when we are already at the start of the buffer */ 1691 static void 1692 ungetsc(int c) 1693 { 1694 struct sretrace_info *rp = retrace_info; 1695 1696 if (backslash_skip) 1697 backslash_skip--; 1698 /* Don't unget EOF... */ 1699 if (source->str == null && c == '\0') 1700 return; 1701 while (rp) { 1702 if (Xlength(rp->xs, rp->xp)) 1703 rp->xp--; 1704 rp = rp->next; 1705 } 1706 ungetsc_i(c); 1707 } 1708 static void 1709 ungetsc_i(int c) 1710 { 1711 if (source->str > source->start) 1712 source->str--; 1713 else { 1714 Source *s; 1715 1716 s = pushs(SREREAD, source->areap); 1717 s->ugbuf[0] = c; s->ugbuf[1] = '\0'; 1718 s->start = s->str = s->ugbuf; 1719 s->next = source; 1720 source = s; 1721 } 1722 } 1723 1724 1725 /* Called to get a char that isn't a \newline sequence. */ 1726 static int 1727 getsc_bn(void) 1728 { 1729 int c, c2; 1730 1731 if (ignore_backslash_newline) 1732 return (o_getsc_u()); 1733 1734 if (backslash_skip == 1) { 1735 backslash_skip = 2; 1736 return (o_getsc_u()); 1737 } 1738 1739 backslash_skip = 0; 1740 1741 while (/* CONSTCOND */ 1) { 1742 c = o_getsc_u(); 1743 if (c == '\\') { 1744 if ((c2 = o_getsc_u()) == '\n') 1745 /* ignore the \newline; get the next char... */ 1746 continue; 1747 ungetsc_i(c2); 1748 backslash_skip = 1; 1749 } 1750 return (c); 1751 } 1752 } 1753 1754 void 1755 yyskiputf8bom(void) 1756 { 1757 int c; 1758 1759 if ((unsigned char)(c = o_getsc_u()) != 0xEF) { 1760 ungetsc_i(c); 1761 return; 1762 } 1763 if ((unsigned char)(c = o_getsc_u()) != 0xBB) { 1764 ungetsc_i(c); 1765 ungetsc_i(0xEF); 1766 return; 1767 } 1768 if ((unsigned char)(c = o_getsc_u()) != 0xBF) { 1769 ungetsc_i(c); 1770 ungetsc_i(0xBB); 1771 ungetsc_i(0xEF); 1772 return; 1773 } 1774 UTFMODE |= 8; 1775 } 1776 1777 static Lex_state * 1778 push_state_i(State_info *si, Lex_state *old_end) 1779 { 1780 Lex_state *news = alloc2(STATE_BSIZE, sizeof(Lex_state), ATEMP); 1781 1782 news[0].ls_base = old_end; 1783 si->base = &news[0]; 1784 si->end = &news[STATE_BSIZE]; 1785 return (&news[1]); 1786 } 1787 1788 static Lex_state * 1789 pop_state_i(State_info *si, Lex_state *old_end) 1790 { 1791 Lex_state *old_base = si->base; 1792 1793 si->base = old_end->ls_base - STATE_BSIZE; 1794 si->end = old_end->ls_base; 1795 1796 afree(old_base, ATEMP); 1797 1798 return (si->base + STATE_BSIZE - 1); 1799 } 1800
