1 /* 2 * Copyright (C) 1984-2011 Mark Nudelman 3 * 4 * You may distribute under the terms of either the GNU General Public 5 * License or the Less License, as specified in the README file. 6 * 7 * For more information about less, or for information on how to 8 * contact the author, see the README file. 9 */ 10 11 12 /* 13 * Routines to decode user commands. 14 * 15 * This is all table driven. 16 * A command table is a sequence of command descriptors. 17 * Each command descriptor is a sequence of bytes with the following format: 18 * <c1><c2>...<cN><0><action> 19 * The characters c1,c2,...,cN are the command string; that is, 20 * the characters which the user must type. 21 * It is terminated by a null <0> byte. 22 * The byte after the null byte is the action code associated 23 * with the command string. 24 * If an action byte is OR-ed with A_EXTRA, this indicates 25 * that the option byte is followed by an extra string. 26 * 27 * There may be many command tables. 28 * The first (default) table is built-in. 29 * Other tables are read in from "lesskey" files. 30 * All the tables are linked together and are searched in order. 31 */ 32 33 #include "less.h" 34 #include "cmd.h" 35 #include "lesskey.h" 36 37 extern int erase_char, erase2_char, kill_char; 38 extern int secure; 39 40 #define SK(k) \ 41 SK_SPECIAL_KEY, (k), 6, 1, 1, 1 42 /* 43 * Command table is ordered roughly according to expected 44 * frequency of use, so the common commands are near the beginning. 45 */ 46 47 static unsigned char cmdtable[] = 48 { 49 '\r',0, A_F_LINE, 50 '\n',0, A_F_LINE, 51 'e',0, A_F_LINE, 52 'j',0, A_F_LINE, 53 SK(SK_DOWN_ARROW),0, A_F_LINE, 54 CONTROL('E'),0, A_F_LINE, 55 CONTROL('N'),0, A_F_LINE, 56 'k',0, A_B_LINE, 57 'y',0, A_B_LINE, 58 CONTROL('Y'),0, A_B_LINE, 59 SK(SK_CONTROL_K),0, A_B_LINE, 60 CONTROL('P'),0, A_B_LINE, 61 SK(SK_UP_ARROW),0, A_B_LINE, 62 'J',0, A_FF_LINE, 63 'K',0, A_BF_LINE, 64 'Y',0, A_BF_LINE, 65 'd',0, A_F_SCROLL, 66 CONTROL('D'),0, A_F_SCROLL, 67 'u',0, A_B_SCROLL, 68 CONTROL('U'),0, A_B_SCROLL, 69 ' ',0, A_F_SCREEN, 70 'f',0, A_F_SCREEN, 71 CONTROL('F'),0, A_F_SCREEN, 72 CONTROL('V'),0, A_F_SCREEN, 73 SK(SK_PAGE_DOWN),0, A_F_SCREEN, 74 'b',0, A_B_SCREEN, 75 CONTROL('B'),0, A_B_SCREEN, 76 ESC,'v',0, A_B_SCREEN, 77 SK(SK_PAGE_UP),0, A_B_SCREEN, 78 'z',0, A_F_WINDOW, 79 'w',0, A_B_WINDOW, 80 ESC,' ',0, A_FF_SCREEN, 81 'F',0, A_F_FOREVER, 82 'R',0, A_FREPAINT, 83 'r',0, A_REPAINT, 84 CONTROL('R'),0, A_REPAINT, 85 CONTROL('L'),0, A_REPAINT, 86 ESC,'u',0, A_UNDO_SEARCH, 87 'g',0, A_GOLINE, 88 SK(SK_HOME),0, A_GOLINE, 89 '<',0, A_GOLINE, 90 ESC,'<',0, A_GOLINE, 91 'p',0, A_PERCENT, 92 '%',0, A_PERCENT, 93 ESC,'[',0, A_LSHIFT, 94 ESC,']',0, A_RSHIFT, 95 ESC,'(',0, A_LSHIFT, 96 ESC,')',0, A_RSHIFT, 97 SK(SK_RIGHT_ARROW),0, A_RSHIFT, 98 SK(SK_LEFT_ARROW),0, A_LSHIFT, 99 '{',0, A_F_BRACKET|A_EXTRA, '{','}',0, 100 '}',0, A_B_BRACKET|A_EXTRA, '{','}',0, 101 '(',0, A_F_BRACKET|A_EXTRA, '(',')',0, 102 ')',0, A_B_BRACKET|A_EXTRA, '(',')',0, 103 '[',0, A_F_BRACKET|A_EXTRA, '[',']',0, 104 ']',0, A_B_BRACKET|A_EXTRA, '[',']',0, 105 ESC,CONTROL('F'),0, A_F_BRACKET, 106 ESC,CONTROL('B'),0, A_B_BRACKET, 107 'G',0, A_GOEND, 108 ESC,'>',0, A_GOEND, 109 '>',0, A_GOEND, 110 SK(SK_END),0, A_GOEND, 111 'P',0, A_GOPOS, 112 113 '0',0, A_DIGIT, 114 '1',0, A_DIGIT, 115 '2',0, A_DIGIT, 116 '3',0, A_DIGIT, 117 '4',0, A_DIGIT, 118 '5',0, A_DIGIT, 119 '6',0, A_DIGIT, 120 '7',0, A_DIGIT, 121 '8',0, A_DIGIT, 122 '9',0, A_DIGIT, 123 '.',0, A_DIGIT, 124 125 '=',0, A_STAT, 126 CONTROL('G'),0, A_STAT, 127 ':','f',0, A_STAT, 128 '/',0, A_F_SEARCH, 129 '?',0, A_B_SEARCH, 130 ESC,'/',0, A_F_SEARCH|A_EXTRA, '*',0, 131 ESC,'?',0, A_B_SEARCH|A_EXTRA, '*',0, 132 'n',0, A_AGAIN_SEARCH, 133 ESC,'n',0, A_T_AGAIN_SEARCH, 134 'N',0, A_REVERSE_SEARCH, 135 ESC,'N',0, A_T_REVERSE_SEARCH, 136 '&',0, A_FILTER, 137 'm',0, A_SETMARK, 138 '\'',0, A_GOMARK, 139 CONTROL('X'),CONTROL('X'),0, A_GOMARK, 140 'E',0, A_EXAMINE, 141 ':','e',0, A_EXAMINE, 142 CONTROL('X'),CONTROL('V'),0, A_EXAMINE, 143 ':','n',0, A_NEXT_FILE, 144 ':','p',0, A_PREV_FILE, 145 't',0, A_NEXT_TAG, 146 'T',0, A_PREV_TAG, 147 ':','x',0, A_INDEX_FILE, 148 ':','d',0, A_REMOVE_FILE, 149 '-',0, A_OPT_TOGGLE, 150 ':','t',0, A_OPT_TOGGLE|A_EXTRA, 't',0, 151 's',0, A_OPT_TOGGLE|A_EXTRA, 'o',0, 152 '_',0, A_DISP_OPTION, 153 '|',0, A_PIPE, 154 'v',0, A_VISUAL, 155 '!',0, A_SHELL, 156 '+',0, A_FIRSTCMD, 157 158 'H',0, A_HELP, 159 'h',0, A_HELP, 160 SK(SK_F1),0, A_HELP, 161 'V',0, A_VERSION, 162 'q',0, A_QUIT, 163 'Q',0, A_QUIT, 164 ':','q',0, A_QUIT, 165 ':','Q',0, A_QUIT, 166 'Z','Z',0, A_QUIT 167 }; 168 169 static unsigned char edittable[] = 170 { 171 '\t',0, EC_F_COMPLETE, /* TAB */ 172 '\17',0, EC_B_COMPLETE, /* BACKTAB */ 173 SK(SK_BACKTAB),0, EC_B_COMPLETE, /* BACKTAB */ 174 ESC,'\t',0, EC_B_COMPLETE, /* ESC TAB */ 175 CONTROL('L'),0, EC_EXPAND, /* CTRL-L */ 176 CONTROL('V'),0, EC_LITERAL, /* BACKSLASH */ 177 CONTROL('A'),0, EC_LITERAL, /* BACKSLASH */ 178 ESC,'l',0, EC_RIGHT, /* ESC l */ 179 SK(SK_RIGHT_ARROW),0, EC_RIGHT, /* RIGHTARROW */ 180 ESC,'h',0, EC_LEFT, /* ESC h */ 181 SK(SK_LEFT_ARROW),0, EC_LEFT, /* LEFTARROW */ 182 ESC,'b',0, EC_W_LEFT, /* ESC b */ 183 ESC,SK(SK_LEFT_ARROW),0, EC_W_LEFT, /* ESC LEFTARROW */ 184 SK(SK_CTL_LEFT_ARROW),0, EC_W_LEFT, /* CTRL-LEFTARROW */ 185 ESC,'w',0, EC_W_RIGHT, /* ESC w */ 186 ESC,SK(SK_RIGHT_ARROW),0, EC_W_RIGHT, /* ESC RIGHTARROW */ 187 SK(SK_CTL_RIGHT_ARROW),0, EC_W_RIGHT, /* CTRL-RIGHTARROW */ 188 ESC,'i',0, EC_INSERT, /* ESC i */ 189 SK(SK_INSERT),0, EC_INSERT, /* INSERT */ 190 ESC,'x',0, EC_DELETE, /* ESC x */ 191 SK(SK_DELETE),0, EC_DELETE, /* DELETE */ 192 ESC,'X',0, EC_W_DELETE, /* ESC X */ 193 ESC,SK(SK_DELETE),0, EC_W_DELETE, /* ESC DELETE */ 194 SK(SK_CTL_DELETE),0, EC_W_DELETE, /* CTRL-DELETE */ 195 SK(SK_CTL_BACKSPACE),0, EC_W_BACKSPACE, /* CTRL-BACKSPACE */ 196 ESC,'\b',0, EC_W_BACKSPACE, /* ESC BACKSPACE */ 197 ESC,'0',0, EC_HOME, /* ESC 0 */ 198 SK(SK_HOME),0, EC_HOME, /* HOME */ 199 ESC,'$',0, EC_END, /* ESC $ */ 200 SK(SK_END),0, EC_END, /* END */ 201 ESC,'k',0, EC_UP, /* ESC k */ 202 SK(SK_UP_ARROW),0, EC_UP, /* UPARROW */ 203 ESC,'j',0, EC_DOWN, /* ESC j */ 204 SK(SK_DOWN_ARROW),0, EC_DOWN, /* DOWNARROW */ 205 CONTROL('G'),0, EC_ABORT, /* CTRL-G */ 206 }; 207 208 /* 209 * Structure to support a list of command tables. 210 */ 211 struct tablelist 212 { 213 struct tablelist *t_next; 214 char *t_start; 215 char *t_end; 216 }; 217 218 /* 219 * List of command tables and list of line-edit tables. 220 */ 221 static struct tablelist *list_fcmd_tables = NULL; 222 static struct tablelist *list_ecmd_tables = NULL; 223 static struct tablelist *list_var_tables = NULL; 224 static struct tablelist *list_sysvar_tables = NULL; 225 226 227 /* 228 * Expand special key abbreviations in a command table. 229 */ 230 static void 231 expand_special_keys(table, len) 232 char *table; 233 int len; 234 { 235 register char *fm; 236 register char *to; 237 register int a; 238 char *repl; 239 int klen; 240 241 for (fm = table; fm < table + len; ) 242 { 243 /* 244 * Rewrite each command in the table with any 245 * special key abbreviations expanded. 246 */ 247 for (to = fm; *fm != '\0'; ) 248 { 249 if (*fm != SK_SPECIAL_KEY) 250 { 251 *to++ = *fm++; 252 continue; 253 } 254 /* 255 * After SK_SPECIAL_KEY, next byte is the type 256 * of special key (one of the SK_* contants), 257 * and the byte after that is the number of bytes, 258 * N, reserved by the abbreviation (including the 259 * SK_SPECIAL_KEY and key type bytes). 260 * Replace all N bytes with the actual bytes 261 * output by the special key on this terminal. 262 */ 263 repl = special_key_str(fm[1]); 264 klen = fm[2] & 0377; 265 fm += klen; 266 if (repl == NULL || (int) strlen(repl) > klen) 267 repl = "\377"; 268 while (*repl != '\0') 269 *to++ = *repl++; 270 } 271 *to++ = '\0'; 272 /* 273 * Fill any unused bytes between end of command and 274 * the action byte with A_SKIP. 275 */ 276 while (to <= fm) 277 *to++ = A_SKIP; 278 fm++; 279 a = *fm++ & 0377; 280 if (a & A_EXTRA) 281 { 282 while (*fm++ != '\0') 283 continue; 284 } 285 } 286 } 287 288 /* 289 * Initialize the command lists. 290 */ 291 public void 292 init_cmds() 293 { 294 /* 295 * Add the default command tables. 296 */ 297 add_fcmd_table((char*)cmdtable, sizeof(cmdtable)); 298 add_ecmd_table((char*)edittable, sizeof(edittable)); 299 #if USERFILE 300 /* 301 * For backwards compatibility, 302 * try to add tables in the OLD system lesskey file. 303 */ 304 #ifdef BINDIR 305 add_hometable(NULL, BINDIR "/.sysless", 1); 306 #endif 307 /* 308 * Try to add the tables in the system lesskey file. 309 */ 310 add_hometable("LESSKEY_SYSTEM", LESSKEYFILE_SYS, 1); 311 /* 312 * Try to add the tables in the standard lesskey file "$HOME/.less". 313 */ 314 add_hometable("LESSKEY", LESSKEYFILE, 0); 315 #endif 316 } 317 318 /* 319 * Add a command table. 320 */ 321 static int 322 add_cmd_table(tlist, buf, len) 323 struct tablelist **tlist; 324 char *buf; 325 int len; 326 { 327 register struct tablelist *t; 328 329 if (len == 0) 330 return (0); 331 /* 332 * Allocate a tablelist structure, initialize it, 333 * and link it into the list of tables. 334 */ 335 if ((t = (struct tablelist *) 336 calloc(1, sizeof(struct tablelist))) == NULL) 337 { 338 return (-1); 339 } 340 expand_special_keys(buf, len); 341 t->t_start = buf; 342 t->t_end = buf + len; 343 t->t_next = *tlist; 344 *tlist = t; 345 return (0); 346 } 347 348 /* 349 * Add a command table. 350 */ 351 public void 352 add_fcmd_table(buf, len) 353 char *buf; 354 int len; 355 { 356 if (add_cmd_table(&list_fcmd_tables, buf, len) < 0) 357 error("Warning: some commands disabled", NULL_PARG); 358 } 359 360 /* 361 * Add an editing command table. 362 */ 363 public void 364 add_ecmd_table(buf, len) 365 char *buf; 366 int len; 367 { 368 if (add_cmd_table(&list_ecmd_tables, buf, len) < 0) 369 error("Warning: some edit commands disabled", NULL_PARG); 370 } 371 372 /* 373 * Add an environment variable table. 374 */ 375 static void 376 add_var_table(tlist, buf, len) 377 struct tablelist **tlist; 378 char *buf; 379 int len; 380 { 381 if (add_cmd_table(tlist, buf, len) < 0) 382 error("Warning: environment variables from lesskey file unavailable", NULL_PARG); 383 } 384 385 /* 386 * Search a single command table for the command string in cmd. 387 */ 388 static int 389 cmd_search(cmd, table, endtable, sp) 390 char *cmd; 391 char *table; 392 char *endtable; 393 char **sp; 394 { 395 register char *p; 396 register char *q; 397 register int a; 398 399 *sp = NULL; 400 for (p = table, q = cmd; p < endtable; p++, q++) 401 { 402 if (*p == *q) 403 { 404 /* 405 * Current characters match. 406 * If we're at the end of the string, we've found it. 407 * Return the action code, which is the character 408 * after the null at the end of the string 409 * in the command table. 410 */ 411 if (*p == '\0') 412 { 413 a = *++p & 0377; 414 while (a == A_SKIP) 415 a = *++p & 0377; 416 if (a == A_END_LIST) 417 { 418 /* 419 * We get here only if the original 420 * cmd string passed in was empty (""). 421 * I don't think that can happen, 422 * but just in case ... 423 */ 424 return (A_UINVALID); 425 } 426 /* 427 * Check for an "extra" string. 428 */ 429 if (a & A_EXTRA) 430 { 431 *sp = ++p; 432 a &= ~A_EXTRA; 433 } 434 return (a); 435 } 436 } else if (*q == '\0') 437 { 438 /* 439 * Hit the end of the user's command, 440 * but not the end of the string in the command table. 441 * The user's command is incomplete. 442 */ 443 return (A_PREFIX); 444 } else 445 { 446 /* 447 * Not a match. 448 * Skip ahead to the next command in the 449 * command table, and reset the pointer 450 * to the beginning of the user's command. 451 */ 452 if (*p == '\0' && p[1] == A_END_LIST) 453 { 454 /* 455 * A_END_LIST is a special marker that tells 456 * us to abort the cmd search. 457 */ 458 return (A_UINVALID); 459 } 460 while (*p++ != '\0') 461 continue; 462 while (*p == A_SKIP) 463 p++; 464 if (*p & A_EXTRA) 465 while (*++p != '\0') 466 continue; 467 q = cmd-1; 468 } 469 } 470 /* 471 * No match found in the entire command table. 472 */ 473 return (A_INVALID); 474 } 475 476 /* 477 * Decode a command character and return the associated action. 478 * The "extra" string, if any, is returned in sp. 479 */ 480 static int 481 cmd_decode(tlist, cmd, sp) 482 struct tablelist *tlist; 483 char *cmd; 484 char **sp; 485 { 486 register struct tablelist *t; 487 register int action = A_INVALID; 488 489 /* 490 * Search thru all the command tables. 491 * Stop when we find an action which is not A_INVALID. 492 */ 493 for (t = tlist; t != NULL; t = t->t_next) 494 { 495 action = cmd_search(cmd, t->t_start, t->t_end, sp); 496 if (action != A_INVALID) 497 break; 498 } 499 if (action == A_UINVALID) 500 action = A_INVALID; 501 return (action); 502 } 503 504 /* 505 * Decode a command from the cmdtables list. 506 */ 507 public int 508 fcmd_decode(cmd, sp) 509 char *cmd; 510 char **sp; 511 { 512 return (cmd_decode(list_fcmd_tables, cmd, sp)); 513 } 514 515 /* 516 * Decode a command from the edittables list. 517 */ 518 public int 519 ecmd_decode(cmd, sp) 520 char *cmd; 521 char **sp; 522 { 523 return (cmd_decode(list_ecmd_tables, cmd, sp)); 524 } 525 526 /* 527 * Get the value of an environment variable. 528 * Looks first in the lesskey file, then in the real environment. 529 */ 530 public char * 531 lgetenv(var) 532 char *var; 533 { 534 int a; 535 char *s; 536 537 a = cmd_decode(list_var_tables, var, &s); 538 if (a == EV_OK) 539 return (s); 540 s = getenv(var); 541 if (s != NULL && *s != '\0') 542 return (s); 543 a = cmd_decode(list_sysvar_tables, var, &s); 544 if (a == EV_OK) 545 return (s); 546 return (NULL); 547 } 548 549 #if USERFILE 550 /* 551 * Get an "integer" from a lesskey file. 552 * Integers are stored in a funny format: 553 * two bytes, low order first, in radix KRADIX. 554 */ 555 static int 556 gint(sp) 557 char **sp; 558 { 559 int n; 560 561 n = *(*sp)++; 562 n += *(*sp)++ * KRADIX; 563 return (n); 564 } 565 566 /* 567 * Process an old (pre-v241) lesskey file. 568 */ 569 static int 570 old_lesskey(buf, len) 571 char *buf; 572 int len; 573 { 574 /* 575 * Old-style lesskey file. 576 * The file must end with either 577 * ...,cmd,0,action 578 * or ...,cmd,0,action|A_EXTRA,string,0 579 * So the last byte or the second to last byte must be zero. 580 */ 581 if (buf[len-1] != '\0' && buf[len-2] != '\0') 582 return (-1); 583 add_fcmd_table(buf, len); 584 return (0); 585 } 586 587 /* 588 * Process a new (post-v241) lesskey file. 589 */ 590 static int 591 new_lesskey(buf, len, sysvar) 592 char *buf; 593 int len; 594 int sysvar; 595 { 596 char *p; 597 register int c; 598 register int n; 599 600 /* 601 * New-style lesskey file. 602 * Extract the pieces. 603 */ 604 if (buf[len-3] != C0_END_LESSKEY_MAGIC || 605 buf[len-2] != C1_END_LESSKEY_MAGIC || 606 buf[len-1] != C2_END_LESSKEY_MAGIC) 607 return (-1); 608 p = buf + 4; 609 for (;;) 610 { 611 c = *p++; 612 switch (c) 613 { 614 case CMD_SECTION: 615 n = gint(&p); 616 add_fcmd_table(p, n); 617 p += n; 618 break; 619 case EDIT_SECTION: 620 n = gint(&p); 621 add_ecmd_table(p, n); 622 p += n; 623 break; 624 case VAR_SECTION: 625 n = gint(&p); 626 add_var_table((sysvar) ? 627 &list_sysvar_tables : &list_var_tables, p, n); 628 p += n; 629 break; 630 case END_SECTION: 631 return (0); 632 default: 633 /* 634 * Unrecognized section type. 635 */ 636 return (-1); 637 } 638 } 639 } 640 641 /* 642 * Set up a user command table, based on a "lesskey" file. 643 */ 644 public int 645 lesskey(filename, sysvar) 646 char *filename; 647 int sysvar; 648 { 649 register char *buf; 650 register POSITION len; 651 register long n; 652 register int f; 653 654 if (secure) 655 return (1); 656 /* 657 * Try to open the lesskey file. 658 */ 659 filename = shell_unquote(filename); 660 f = open(filename, OPEN_READ); 661 free(filename); 662 if (f < 0) 663 return (1); 664 665 /* 666 * Read the file into a buffer. 667 * We first figure out the size of the file and allocate space for it. 668 * {{ Minimal error checking is done here. 669 * A garbage .less file will produce strange results. 670 * To avoid a large amount of error checking code here, we 671 * rely on the lesskey program to generate a good .less file. }} 672 */ 673 len = filesize(f); 674 if (len == NULL_POSITION || len < 3) 675 { 676 /* 677 * Bad file (valid file must have at least 3 chars). 678 */ 679 close(f); 680 return (-1); 681 } 682 if ((buf = (char *) calloc((int)len, sizeof(char))) == NULL) 683 { 684 close(f); 685 return (-1); 686 } 687 if (lseek(f, (off_t)0, SEEK_SET) == BAD_LSEEK) 688 { 689 free(buf); 690 close(f); 691 return (-1); 692 } 693 n = read(f, buf, (unsigned int) len); 694 close(f); 695 if (n != len) 696 { 697 free(buf); 698 return (-1); 699 } 700 701 /* 702 * Figure out if this is an old-style (before version 241) 703 * or new-style lesskey file format. 704 */ 705 if (buf[0] != C0_LESSKEY_MAGIC || buf[1] != C1_LESSKEY_MAGIC || 706 buf[2] != C2_LESSKEY_MAGIC || buf[3] != C3_LESSKEY_MAGIC) 707 return (old_lesskey(buf, (int)len)); 708 return (new_lesskey(buf, (int)len, sysvar)); 709 } 710 711 /* 712 * Add the standard lesskey file "$HOME/.less" 713 */ 714 public void 715 add_hometable(envname, def_filename, sysvar) 716 char *envname; 717 char *def_filename; 718 int sysvar; 719 { 720 char *filename; 721 PARG parg; 722 723 if (envname != NULL && (filename = lgetenv(envname)) != NULL) 724 filename = save(filename); 725 else if (sysvar) 726 filename = save(def_filename); 727 else 728 filename = homefile(def_filename); 729 if (filename == NULL) 730 return; 731 if (lesskey(filename, sysvar) < 0) 732 { 733 parg.p_string = filename; 734 error("Cannot use lesskey file \"%s\"", &parg); 735 } 736 free(filename); 737 } 738 #endif 739 740 /* 741 * See if a char is a special line-editing command. 742 */ 743 public int 744 editchar(c, flags) 745 int c; 746 int flags; 747 { 748 int action; 749 int nch; 750 char *s; 751 char usercmd[MAX_CMDLEN+1]; 752 753 /* 754 * An editing character could actually be a sequence of characters; 755 * for example, an escape sequence sent by pressing the uparrow key. 756 * To match the editing string, we use the command decoder 757 * but give it the edit-commands command table 758 * This table is constructed to match the user's keyboard. 759 */ 760 if (c == erase_char || c == erase2_char) 761 return (EC_BACKSPACE); 762 if (c == kill_char) 763 return (EC_LINEKILL); 764 765 /* 766 * Collect characters in a buffer. 767 * Start with the one we have, and get more if we need them. 768 */ 769 nch = 0; 770 do { 771 if (nch > 0) 772 c = getcc(); 773 usercmd[nch] = c; 774 usercmd[nch+1] = '\0'; 775 nch++; 776 action = ecmd_decode(usercmd, &s); 777 } while (action == A_PREFIX); 778 779 if (flags & EC_NORIGHTLEFT) 780 { 781 switch (action) 782 { 783 case EC_RIGHT: 784 case EC_LEFT: 785 action = A_INVALID; 786 break; 787 } 788 } 789 #if CMD_HISTORY 790 if (flags & EC_NOHISTORY) 791 { 792 /* 793 * The caller says there is no history list. 794 * Reject any history-manipulation action. 795 */ 796 switch (action) 797 { 798 case EC_UP: 799 case EC_DOWN: 800 action = A_INVALID; 801 break; 802 } 803 } 804 #endif 805 #if TAB_COMPLETE_FILENAME 806 if (flags & EC_NOCOMPLETE) 807 { 808 /* 809 * The caller says we don't want any filename completion cmds. 810 * Reject them. 811 */ 812 switch (action) 813 { 814 case EC_F_COMPLETE: 815 case EC_B_COMPLETE: 816 case EC_EXPAND: 817 action = A_INVALID; 818 break; 819 } 820 } 821 #endif 822 if ((flags & EC_PEEK) || action == A_INVALID) 823 { 824 /* 825 * We're just peeking, or we didn't understand the command. 826 * Unget all the characters we read in the loop above. 827 * This does NOT include the original character that was 828 * passed in as a parameter. 829 */ 830 while (nch > 1) 831 { 832 ungetcc(usercmd[--nch]); 833 } 834 } else 835 { 836 if (s != NULL) 837 ungetsc(s); 838 } 839 return action; 840 } 841 842