1/* 2 * Copyright (C) 1984-2021 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, see the README file. 8 */ 9 10 11/* 12 * Routines to decode user commands. 13 * 14 * This is all table driven. 15 * A command table is a sequence of command descriptors. 16 * Each command descriptor is a sequence of bytes with the following format: 17 * <c1><c2>...<cN><0><action> 18 * The characters c1,c2,...,cN are the command string; that is, 19 * the characters which the user must type. 20 * It is terminated by a null <0> byte. 21 * The byte after the null byte is the action code associated 22 * with the command string. 23 * If an action byte is OR-ed with A_EXTRA, this indicates 24 * that the option byte is followed by an extra string. 25 * 26 * There may be many command tables. 27 * The first (default) table is built-in. 28 * Other tables are read in from "lesskey" files. 29 * All the tables are linked together and are searched in order. 30 */ 31 32#include "less.h" 33#include "cmd.h" 34#include "lesskey.h" 35 36extern int erase_char, erase2_char, kill_char; 37extern int secure; 38extern int mousecap; 39extern int screen_trashed; 40extern int sc_height; 41 42#define SK(k) \ 43 SK_SPECIAL_KEY, (k), 6, 1, 1, 1 44/* 45 * Command table is ordered roughly according to expected 46 * frequency of use, so the common commands are near the beginning. 47 */ 48 49static unsigned char cmdtable[] = 50{ 51 '\r',0, A_F_LINE, 52 '\n',0, A_F_LINE, 53 'e',0, A_F_LINE, 54 'j',0, A_F_LINE, 55 SK(SK_DOWN_ARROW),0, A_F_LINE, 56 CONTROL('E'),0, A_F_LINE, 57 CONTROL('N'),0, A_F_LINE, 58 'k',0, A_B_LINE, 59 'y',0, A_B_LINE, 60 CONTROL('Y'),0, A_B_LINE, 61 SK(SK_CONTROL_K),0, A_B_LINE, 62 CONTROL('P'),0, A_B_LINE, 63 SK(SK_UP_ARROW),0, A_B_LINE, 64 'J',0, A_FF_LINE, 65 'K',0, A_BF_LINE, 66 'Y',0, A_BF_LINE, 67 'd',0, A_F_SCROLL, 68 CONTROL('D'),0, A_F_SCROLL, 69 'u',0, A_B_SCROLL, 70 CONTROL('U'),0, A_B_SCROLL, 71 ESC,'[','M',0, A_X11MOUSE_IN, 72 ESC,'[','<',0, A_X116MOUSE_IN, 73 ' ',0, A_F_SCREEN, 74 'f',0, A_F_SCREEN, 75 CONTROL('F'),0, A_F_SCREEN, 76 CONTROL('V'),0, A_F_SCREEN, 77 SK(SK_PAGE_DOWN),0, A_F_SCREEN, 78 'b',0, A_B_SCREEN, 79 CONTROL('B'),0, A_B_SCREEN, 80 ESC,'v',0, A_B_SCREEN, 81 SK(SK_PAGE_UP),0, A_B_SCREEN, 82 'z',0, A_F_WINDOW, 83 'w',0, A_B_WINDOW, 84 ESC,' ',0, A_FF_SCREEN, 85 'F',0, A_F_FOREVER, 86 ESC,'F',0, A_F_UNTIL_HILITE, 87 'R',0, A_FREPAINT, 88 'r',0, A_REPAINT, 89 CONTROL('R'),0, A_REPAINT, 90 CONTROL('L'),0, A_REPAINT, 91 ESC,'u',0, A_UNDO_SEARCH, 92 ESC,'U',0, A_CLR_SEARCH, 93 'g',0, A_GOLINE, 94 SK(SK_HOME),0, A_GOLINE, 95 '<',0, A_GOLINE, 96 ESC,'<',0, A_GOLINE, 97 'p',0, A_PERCENT, 98 '%',0, A_PERCENT, 99 ESC,'[',0, A_LSHIFT, 100 ESC,']',0, A_RSHIFT, 101 ESC,'(',0, A_LSHIFT, 102 ESC,')',0, A_RSHIFT, 103 ESC,'{',0, A_LLSHIFT, 104 ESC,'}',0, A_RRSHIFT, 105 SK(SK_RIGHT_ARROW),0, A_RSHIFT, 106 SK(SK_LEFT_ARROW),0, A_LSHIFT, 107 SK(SK_CTL_RIGHT_ARROW),0, A_RRSHIFT, 108 SK(SK_CTL_LEFT_ARROW),0, A_LLSHIFT, 109 '{',0, A_F_BRACKET|A_EXTRA, '{','}',0, 110 '}',0, A_B_BRACKET|A_EXTRA, '{','}',0, 111 '(',0, A_F_BRACKET|A_EXTRA, '(',')',0, 112 ')',0, A_B_BRACKET|A_EXTRA, '(',')',0, 113 '[',0, A_F_BRACKET|A_EXTRA, '[',']',0, 114 ']',0, A_B_BRACKET|A_EXTRA, '[',']',0, 115 ESC,CONTROL('F'),0, A_F_BRACKET, 116 ESC,CONTROL('B'),0, A_B_BRACKET, 117 'G',0, A_GOEND, 118 ESC,'G',0, A_GOEND_BUF, 119 ESC,'>',0, A_GOEND, 120 '>',0, A_GOEND, 121 SK(SK_END),0, A_GOEND, 122 'P',0, A_GOPOS, 123 124 '0',0, A_DIGIT, 125 '1',0, A_DIGIT, 126 '2',0, A_DIGIT, 127 '3',0, A_DIGIT, 128 '4',0, A_DIGIT, 129 '5',0, A_DIGIT, 130 '6',0, A_DIGIT, 131 '7',0, A_DIGIT, 132 '8',0, A_DIGIT, 133 '9',0, A_DIGIT, 134 '.',0, A_DIGIT, 135 136 '=',0, A_STAT, 137 CONTROL('G'),0, A_STAT, 138 ':','f',0, A_STAT, 139 '/',0, A_F_SEARCH, 140 '?',0, A_B_SEARCH, 141 ESC,'/',0, A_F_SEARCH|A_EXTRA, '*',0, 142 ESC,'?',0, A_B_SEARCH|A_EXTRA, '*',0, 143 'n',0, A_AGAIN_SEARCH, 144 ESC,'n',0, A_T_AGAIN_SEARCH, 145 'N',0, A_REVERSE_SEARCH, 146 ESC,'N',0, A_T_REVERSE_SEARCH, 147 '&',0, A_FILTER, 148 'm',0, A_SETMARK, 149 'M',0, A_SETMARKBOT, 150 ESC,'m',0, A_CLRMARK, 151 '\'',0, A_GOMARK, 152 CONTROL('X'),CONTROL('X'),0, A_GOMARK, 153 'E',0, A_EXAMINE, 154 ':','e',0, A_EXAMINE, 155 CONTROL('X'),CONTROL('V'),0, A_EXAMINE, 156 ':','n',0, A_NEXT_FILE, 157 ':','p',0, A_PREV_FILE, 158 't',0, A_NEXT_TAG, 159 'T',0, A_PREV_TAG, 160 ':','x',0, A_INDEX_FILE, 161 ':','d',0, A_REMOVE_FILE, 162 '-',0, A_OPT_TOGGLE, 163 ':','t',0, A_OPT_TOGGLE|A_EXTRA, 't',0, 164 's',0, A_OPT_TOGGLE|A_EXTRA, 'o',0, 165 '_',0, A_DISP_OPTION, 166 '|',0, A_PIPE, 167 'v',0, A_VISUAL, 168 '!',0, A_SHELL, 169 '+',0, A_FIRSTCMD, 170 171 'H',0, A_HELP, 172 'h',0, A_HELP, 173 SK(SK_F1),0, A_HELP, 174 'V',0, A_VERSION, 175 'q',0, A_QUIT, 176 'Q',0, A_QUIT, 177 ':','q',0, A_QUIT, 178 ':','Q',0, A_QUIT, 179 'Z','Z',0, A_QUIT 180}; 181 182static unsigned char edittable[] = 183{ 184 '\t',0, EC_F_COMPLETE, /* TAB */ 185 '\17',0, EC_B_COMPLETE, /* BACKTAB */ 186 SK(SK_BACKTAB),0, EC_B_COMPLETE, /* BACKTAB */ 187 ESC,'\t',0, EC_B_COMPLETE, /* ESC TAB */ 188 CONTROL('L'),0, EC_EXPAND, /* CTRL-L */ 189 CONTROL('V'),0, EC_LITERAL, /* BACKSLASH */ 190 CONTROL('A'),0, EC_LITERAL, /* BACKSLASH */ 191 ESC,'l',0, EC_RIGHT, /* ESC l */ 192 SK(SK_RIGHT_ARROW),0, EC_RIGHT, /* RIGHTARROW */ 193 ESC,'h',0, EC_LEFT, /* ESC h */ 194 SK(SK_LEFT_ARROW),0, EC_LEFT, /* LEFTARROW */ 195 ESC,'b',0, EC_W_LEFT, /* ESC b */ 196 ESC,SK(SK_LEFT_ARROW),0, EC_W_LEFT, /* ESC LEFTARROW */ 197 SK(SK_CTL_LEFT_ARROW),0, EC_W_LEFT, /* CTRL-LEFTARROW */ 198 ESC,'w',0, EC_W_RIGHT, /* ESC w */ 199 ESC,SK(SK_RIGHT_ARROW),0, EC_W_RIGHT, /* ESC RIGHTARROW */ 200 SK(SK_CTL_RIGHT_ARROW),0, EC_W_RIGHT, /* CTRL-RIGHTARROW */ 201 ESC,'i',0, EC_INSERT, /* ESC i */ 202 SK(SK_INSERT),0, EC_INSERT, /* INSERT */ 203 ESC,'x',0, EC_DELETE, /* ESC x */ 204 SK(SK_DELETE),0, EC_DELETE, /* DELETE */ 205 ESC,'X',0, EC_W_DELETE, /* ESC X */ 206 ESC,SK(SK_DELETE),0, EC_W_DELETE, /* ESC DELETE */ 207 SK(SK_CTL_DELETE),0, EC_W_DELETE, /* CTRL-DELETE */ 208 SK(SK_CTL_BACKSPACE),0, EC_W_BACKSPACE, /* CTRL-BACKSPACE */ 209 ESC,'\b',0, EC_W_BACKSPACE, /* ESC BACKSPACE */ 210 ESC,'0',0, EC_HOME, /* ESC 0 */ 211 SK(SK_HOME),0, EC_HOME, /* HOME */ 212 ESC,'$',0, EC_END, /* ESC $ */ 213 SK(SK_END),0, EC_END, /* END */ 214 ESC,'k',0, EC_UP, /* ESC k */ 215 SK(SK_UP_ARROW),0, EC_UP, /* UPARROW */ 216 ESC,'j',0, EC_DOWN, /* ESC j */ 217 SK(SK_DOWN_ARROW),0, EC_DOWN, /* DOWNARROW */ 218 CONTROL('G'),0, EC_ABORT, /* CTRL-G */ 219 ESC,'[','M',0, EC_X11MOUSE, /* X11 mouse report */ 220 ESC,'[','<',0, EC_X116MOUSE, /* X11 1006 mouse report */ 221}; 222 223/* 224 * Structure to support a list of command tables. 225 */ 226struct tablelist 227{ 228 struct tablelist *t_next; 229 char *t_start; 230 char *t_end; 231}; 232 233/* 234 * List of command tables and list of line-edit tables. 235 */ 236static struct tablelist *list_fcmd_tables = NULL; 237static struct tablelist *list_ecmd_tables = NULL; 238static struct tablelist *list_var_tables = NULL; 239static struct tablelist *list_sysvar_tables = NULL; 240 241 242/* 243 * Expand special key abbreviations in a command table. 244 */ 245 static void 246expand_special_keys(table, len) 247 char *table; 248 int len; 249{ 250 char *fm; 251 char *to; 252 int a; 253 char *repl; 254 int klen; 255 256 for (fm = table; fm < table + len; ) 257 { 258 /* 259 * Rewrite each command in the table with any 260 * special key abbreviations expanded. 261 */ 262 for (to = fm; *fm != '\0'; ) 263 { 264 if (*fm != SK_SPECIAL_KEY) 265 { 266 *to++ = *fm++; 267 continue; 268 } 269 /* 270 * After SK_SPECIAL_KEY, next byte is the type 271 * of special key (one of the SK_* contants), 272 * and the byte after that is the number of bytes, 273 * N, reserved by the abbreviation (including the 274 * SK_SPECIAL_KEY and key type bytes). 275 * Replace all N bytes with the actual bytes 276 * output by the special key on this terminal. 277 */ 278 repl = special_key_str(fm[1]); 279 klen = fm[2] & 0377; 280 fm += klen; 281 if (repl == NULL || (int) strlen(repl) > klen) 282 repl = "\377"; 283 while (*repl != '\0') 284 *to++ = *repl++; 285 } 286 *to++ = '\0'; 287 /* 288 * Fill any unused bytes between end of command and 289 * the action byte with A_SKIP. 290 */ 291 while (to <= fm) 292 *to++ = A_SKIP; 293 fm++; 294 a = *fm++ & 0377; 295 if (a & A_EXTRA) 296 { 297 while (*fm++ != '\0') 298 continue; 299 } 300 } 301} 302 303/* 304 * Expand special key abbreviations in a list of command tables. 305 */ 306 static void 307expand_cmd_table(tlist) 308 struct tablelist *tlist; 309{ 310 struct tablelist *t; 311 for (t = tlist; t != NULL; t = t->t_next) 312 { 313 expand_special_keys(t->t_start, t->t_end - t->t_start); 314 } 315} 316 317/* 318 * Expand special key abbreviations in all command tables. 319 */ 320 public void 321expand_cmd_tables(VOID_PARAM) 322{ 323 expand_cmd_table(list_fcmd_tables); 324 expand_cmd_table(list_ecmd_tables); 325 expand_cmd_table(list_var_tables); 326 expand_cmd_table(list_sysvar_tables); 327} 328 329 330/* 331 * Initialize the command lists. 332 */ 333 public void 334init_cmds(VOID_PARAM) 335{ 336 /* 337 * Add the default command tables. 338 */ 339 add_fcmd_table((char*)cmdtable, sizeof(cmdtable)); 340 add_ecmd_table((char*)edittable, sizeof(edittable)); 341#if USERFILE 342 /* 343 * For backwards compatibility, 344 * try to add tables in the OLD system lesskey file. 345 */ 346#ifdef BINDIR 347 add_hometable(NULL, BINDIR "/.sysless", 1); 348#endif 349 /* 350 * Try to add the tables in the system lesskey file. 351 */ 352 add_hometable("LESSKEY_SYSTEM", LESSKEYFILE_SYS, 1); 353 /* 354 * Try to add the tables in the standard lesskey file "$HOME/.less". 355 */ 356 add_hometable("LESSKEY", LESSKEYFILE, 0); 357#endif 358} 359 360/* 361 * Add a command table. 362 */ 363 static int 364add_cmd_table(tlist, buf, len) 365 struct tablelist **tlist; 366 char *buf; 367 int len; 368{ 369 struct tablelist *t; 370 371 if (len == 0) 372 return (0); 373 /* 374 * Allocate a tablelist structure, initialize it, 375 * and link it into the list of tables. 376 */ 377 if ((t = (struct tablelist *) 378 calloc(1, sizeof(struct tablelist))) == NULL) 379 { 380 return (-1); 381 } 382 t->t_start = buf; 383 t->t_end = buf + len; 384 t->t_next = *tlist; 385 *tlist = t; 386 return (0); 387} 388 389/* 390 * Add a command table. 391 */ 392 public void 393add_fcmd_table(buf, len) 394 char *buf; 395 int len; 396{ 397 if (add_cmd_table(&list_fcmd_tables, buf, len) < 0) 398 error("Warning: some commands disabled", NULL_PARG); 399} 400 401/* 402 * Add an editing command table. 403 */ 404 public void 405add_ecmd_table(buf, len) 406 char *buf; 407 int len; 408{ 409 if (add_cmd_table(&list_ecmd_tables, buf, len) < 0) 410 error("Warning: some edit commands disabled", NULL_PARG); 411} 412 413/* 414 * Add an environment variable table. 415 */ 416 static void 417add_var_table(tlist, buf, len) 418 struct tablelist **tlist; 419 char *buf; 420 int len; 421{ 422 if (add_cmd_table(tlist, buf, len) < 0) 423 error("Warning: environment variables from lesskey file unavailable", NULL_PARG); 424} 425 426/* 427 * Return action for a mouse wheel down event. 428 */ 429 static int 430mouse_wheel_down(VOID_PARAM) 431{ 432 return ((mousecap == OPT_ONPLUS) ? A_B_MOUSE : A_F_MOUSE); 433} 434 435/* 436 * Return action for a mouse wheel up event. 437 */ 438 static int 439mouse_wheel_up(VOID_PARAM) 440{ 441 return ((mousecap == OPT_ONPLUS) ? A_F_MOUSE : A_B_MOUSE); 442} 443 444/* 445 * Return action for a mouse button release event. 446 */ 447 static int 448mouse_button_rel(x, y) 449 int x; 450 int y; 451{ 452 /* 453 * {{ It would be better to return an action and then do this 454 * in commands() but it's nontrivial to pass y to it. }} 455 */ 456 if (y < sc_height-1) 457 { 458 setmark('#', y); 459 screen_trashed = 1; 460 } 461 return (A_NOACTION); 462} 463 464/* 465 * Read a decimal integer. Return the integer and set *pterm to the terminating char. 466 */ 467 static int 468getcc_int(pterm) 469 char* pterm; 470{ 471 int num = 0; 472 int digits = 0; 473 for (;;) 474 { 475 char ch = getcc(); 476 if (ch < '0' || ch > '9') 477 { 478 if (pterm != NULL) *pterm = ch; 479 if (digits == 0) 480 return (-1); 481 return (num); 482 } 483 num = (10 * num) + (ch - '0'); 484 ++digits; 485 } 486} 487 488/* 489 * Read suffix of mouse input and return the action to take. 490 * The prefix ("\e[M") has already been read. 491 */ 492 static int 493x11mouse_action(skip) 494 int skip; 495{ 496 int b = getcc() - X11MOUSE_OFFSET; 497 int x = getcc() - X11MOUSE_OFFSET-1; 498 int y = getcc() - X11MOUSE_OFFSET-1; 499 if (skip) 500 return (A_NOACTION); 501 switch (b) { 502 default: 503 return (A_NOACTION); 504 case X11MOUSE_WHEEL_DOWN: 505 return mouse_wheel_down(); 506 case X11MOUSE_WHEEL_UP: 507 return mouse_wheel_up(); 508 case X11MOUSE_BUTTON_REL: 509 return mouse_button_rel(x, y); 510 } 511} 512 513/* 514 * Read suffix of mouse input and return the action to take. 515 * The prefix ("\e[<") has already been read. 516 */ 517 static int 518x116mouse_action(skip) 519 int skip; 520{ 521 char ch; 522 int x, y; 523 int b = getcc_int(&ch); 524 if (b < 0 || ch != ';') return (A_NOACTION); 525 x = getcc_int(&ch) - 1; 526 if (x < 0 || ch != ';') return (A_NOACTION); 527 y = getcc_int(&ch) - 1; 528 if (y < 0) return (A_NOACTION); 529 if (skip) 530 return (A_NOACTION); 531 switch (b) { 532 case X11MOUSE_WHEEL_DOWN: 533 return mouse_wheel_down(); 534 case X11MOUSE_WHEEL_UP: 535 return mouse_wheel_up(); 536 default: 537 if (ch != 'm') return (A_NOACTION); 538 return mouse_button_rel(x, y); 539 } 540} 541 542/* 543 * Search a single command table for the command string in cmd. 544 */ 545 static int 546cmd_search(cmd, table, endtable, sp) 547 char *cmd; 548 char *table; 549 char *endtable; 550 char **sp; 551{ 552 char *p; 553 char *q; 554 int a; 555 556 *sp = NULL; 557 for (p = table, q = cmd; p < endtable; p++, q++) 558 { 559 if (*p == *q) 560 { 561 /* 562 * Current characters match. 563 * If we're at the end of the string, we've found it. 564 * Return the action code, which is the character 565 * after the null at the end of the string 566 * in the command table. 567 */ 568 if (*p == '\0') 569 { 570 a = *++p & 0377; 571 while (a == A_SKIP) 572 a = *++p & 0377; 573 if (a == A_END_LIST) 574 { 575 /* 576 * We get here only if the original 577 * cmd string passed in was empty (""). 578 * I don't think that can happen, 579 * but just in case ... 580 */ 581 return (A_UINVALID); 582 } 583 /* 584 * Check for an "extra" string. 585 */ 586 if (a & A_EXTRA) 587 { 588 *sp = ++p; 589 a &= ~A_EXTRA; 590 } 591 if (a == A_X11MOUSE_IN) 592 a = x11mouse_action(0); 593 else if (a == A_X116MOUSE_IN) 594 a = x116mouse_action(0); 595 return (a); 596 } 597 } else if (*q == '\0') 598 { 599 /* 600 * Hit the end of the user's command, 601 * but not the end of the string in the command table. 602 * The user's command is incomplete. 603 */ 604 return (A_PREFIX); 605 } else 606 { 607 /* 608 * Not a match. 609 * Skip ahead to the next command in the 610 * command table, and reset the pointer 611 * to the beginning of the user's command. 612 */ 613 if (*p == '\0' && p[1] == A_END_LIST) 614 { 615 /* 616 * A_END_LIST is a special marker that tells 617 * us to abort the cmd search. 618 */ 619 return (A_UINVALID); 620 } 621 while (*p++ != '\0') 622 continue; 623 while (*p == A_SKIP) 624 p++; 625 if (*p & A_EXTRA) 626 while (*++p != '\0') 627 continue; 628 q = cmd-1; 629 } 630 } 631 /* 632 * No match found in the entire command table. 633 */ 634 return (A_INVALID); 635} 636 637/* 638 * Decode a command character and return the associated action. 639 * The "extra" string, if any, is returned in sp. 640 */ 641 static int 642cmd_decode(tlist, cmd, sp) 643 struct tablelist *tlist; 644 char *cmd; 645 char **sp; 646{ 647 struct tablelist *t; 648 int action = A_INVALID; 649 650 /* 651 * Search thru all the command tables. 652 * Stop when we find an action which is not A_INVALID. 653 */ 654 for (t = tlist; t != NULL; t = t->t_next) 655 { 656 action = cmd_search(cmd, t->t_start, t->t_end, sp); 657 if (action != A_INVALID) 658 break; 659 } 660 if (action == A_UINVALID) 661 action = A_INVALID; 662 return (action); 663} 664 665/* 666 * Decode a command from the cmdtables list. 667 */ 668 public int 669fcmd_decode(cmd, sp) 670 char *cmd; 671 char **sp; 672{ 673 return (cmd_decode(list_fcmd_tables, cmd, sp)); 674} 675 676/* 677 * Decode a command from the edittables list. 678 */ 679 public int 680ecmd_decode(cmd, sp) 681 char *cmd; 682 char **sp; 683{ 684 return (cmd_decode(list_ecmd_tables, cmd, sp)); 685} 686 687/* 688 * Get the value of an environment variable. 689 * Looks first in the lesskey file, then in the real environment. 690 */ 691 public char * 692lgetenv(var) 693 char *var; 694{ 695 int a; 696 char *s; 697 698 a = cmd_decode(list_var_tables, var, &s); 699 if (a == EV_OK) 700 return (s); 701 s = getenv(var); 702 if (s != NULL && *s != '\0') 703 return (s); 704 a = cmd_decode(list_sysvar_tables, var, &s); 705 if (a == EV_OK) 706 return (s); 707 return (NULL); 708} 709 710/* 711 * Is a string null or empty? 712 */ 713 public int 714isnullenv(s) 715 char* s; 716{ 717 return (s == NULL || *s == '\0'); 718} 719 720#if USERFILE 721/* 722 * Get an "integer" from a lesskey file. 723 * Integers are stored in a funny format: 724 * two bytes, low order first, in radix KRADIX. 725 */ 726 static int 727gint(sp) 728 char **sp; 729{ 730 int n; 731 732 n = *(*sp)++; 733 n += *(*sp)++ * KRADIX; 734 return (n); 735} 736 737/* 738 * Process an old (pre-v241) lesskey file. 739 */ 740 static int 741old_lesskey(buf, len) 742 char *buf; 743 int len; 744{ 745 /* 746 * Old-style lesskey file. 747 * The file must end with either 748 * ...,cmd,0,action 749 * or ...,cmd,0,action|A_EXTRA,string,0 750 * So the last byte or the second to last byte must be zero. 751 */ 752 if (buf[len-1] != '\0' && buf[len-2] != '\0') 753 return (-1); 754 add_fcmd_table(buf, len); 755 return (0); 756} 757 758/* 759 * Process a new (post-v241) lesskey file. 760 */ 761 static int 762new_lesskey(buf, len, sysvar) 763 char *buf; 764 int len; 765 int sysvar; 766{ 767 char *p; 768 int c; 769 int n; 770 771 /* 772 * New-style lesskey file. 773 * Extract the pieces. 774 */ 775 if (buf[len-3] != C0_END_LESSKEY_MAGIC || 776 buf[len-2] != C1_END_LESSKEY_MAGIC || 777 buf[len-1] != C2_END_LESSKEY_MAGIC) 778 return (-1); 779 p = buf + 4; 780 for (;;) 781 { 782 c = *p++; 783 switch (c) 784 { 785 case CMD_SECTION: 786 n = gint(&p); 787 add_fcmd_table(p, n); 788 p += n; 789 break; 790 case EDIT_SECTION: 791 n = gint(&p); 792 add_ecmd_table(p, n); 793 p += n; 794 break; 795 case VAR_SECTION: 796 n = gint(&p); 797 add_var_table((sysvar) ? 798 &list_sysvar_tables : &list_var_tables, p, n); 799 p += n; 800 break; 801 case END_SECTION: 802 return (0); 803 default: 804 /* 805 * Unrecognized section type. 806 */ 807 return (-1); 808 } 809 } 810} 811 812/* 813 * Set up a user command table, based on a "lesskey" file. 814 */ 815 public int 816lesskey(filename, sysvar) 817 char *filename; 818 int sysvar; 819{ 820 char *buf; 821 POSITION len; 822 long n; 823 int f; 824 825 if (secure) 826 return (1); 827 /* 828 * Try to open the lesskey file. 829 */ 830 f = open(filename, OPEN_READ); 831 if (f < 0) 832 return (1); 833 834 /* 835 * Read the file into a buffer. 836 * We first figure out the size of the file and allocate space for it. 837 * {{ Minimal error checking is done here. 838 * A garbage .less file will produce strange results. 839 * To avoid a large amount of error checking code here, we 840 * rely on the lesskey program to generate a good .less file. }} 841 */ 842 len = filesize(f); 843 if (len == NULL_POSITION || len < 3) 844 { 845 /* 846 * Bad file (valid file must have at least 3 chars). 847 */ 848 close(f); 849 return (-1); 850 } 851 if ((buf = (char *) calloc((int)len, sizeof(char))) == NULL) 852 { 853 close(f); 854 return (-1); 855 } 856 if (lseek(f, (off_t)0, SEEK_SET) == BAD_LSEEK) 857 { 858 free(buf); 859 close(f); 860 return (-1); 861 } 862 n = read(f, buf, (unsigned int) len); 863 close(f); 864 if (n != len) 865 { 866 free(buf); 867 return (-1); 868 } 869 870 /* 871 * Figure out if this is an old-style (before version 241) 872 * or new-style lesskey file format. 873 */ 874 if (buf[0] != C0_LESSKEY_MAGIC || buf[1] != C1_LESSKEY_MAGIC || 875 buf[2] != C2_LESSKEY_MAGIC || buf[3] != C3_LESSKEY_MAGIC) 876 return (old_lesskey(buf, (int)len)); 877 return (new_lesskey(buf, (int)len, sysvar)); 878} 879 880/* 881 * Add the standard lesskey file "$HOME/.less" 882 */ 883 public void 884add_hometable(envname, def_filename, sysvar) 885 char *envname; 886 char *def_filename; 887 int sysvar; 888{ 889 char *filename; 890 PARG parg; 891 892 if (envname != NULL && (filename = lgetenv(envname)) != NULL) 893 filename = save(filename); 894 else if (sysvar) 895 filename = save(def_filename); 896 else 897 filename = homefile(def_filename); 898 if (filename == NULL) 899 return; 900 if (lesskey(filename, sysvar) < 0) 901 { 902 parg.p_string = filename; 903 error("Cannot use lesskey file \"%s\"", &parg); 904 } 905 free(filename); 906} 907#endif 908 909/* 910 * See if a char is a special line-editing command. 911 */ 912 public int 913editchar(c, flags) 914 int c; 915 int flags; 916{ 917 int action; 918 int nch; 919 char *s; 920 char usercmd[MAX_CMDLEN+1]; 921 922 /* 923 * An editing character could actually be a sequence of characters; 924 * for example, an escape sequence sent by pressing the uparrow key. 925 * To match the editing string, we use the command decoder 926 * but give it the edit-commands command table 927 * This table is constructed to match the user's keyboard. 928 */ 929 if (c == erase_char || c == erase2_char) 930 return (EC_BACKSPACE); 931 if (c == kill_char) 932 { 933#if MSDOS_COMPILER==WIN32C 934 if (!win32_kbhit()) 935#endif 936 return (EC_LINEKILL); 937 } 938 939 /* 940 * Collect characters in a buffer. 941 * Start with the one we have, and get more if we need them. 942 */ 943 nch = 0; 944 do { 945 if (nch > 0) 946 c = getcc(); 947 usercmd[nch] = c; 948 usercmd[nch+1] = '\0'; 949 nch++; 950 action = ecmd_decode(usercmd, &s); 951 } while (action == A_PREFIX && nch < MAX_CMDLEN); 952 953 if (action == EC_X11MOUSE) 954 return (x11mouse_action(1)); 955 if (action == EC_X116MOUSE) 956 return (x116mouse_action(1)); 957 958 if (flags & ECF_NORIGHTLEFT) 959 { 960 switch (action) 961 { 962 case EC_RIGHT: 963 case EC_LEFT: 964 action = A_INVALID; 965 break; 966 } 967 } 968#if CMD_HISTORY 969 if (flags & ECF_NOHISTORY) 970 { 971 /* 972 * The caller says there is no history list. 973 * Reject any history-manipulation action. 974 */ 975 switch (action) 976 { 977 case EC_UP: 978 case EC_DOWN: 979 action = A_INVALID; 980 break; 981 } 982 } 983#endif 984#if TAB_COMPLETE_FILENAME 985 if (flags & ECF_NOCOMPLETE) 986 { 987 /* 988 * The caller says we don't want any filename completion cmds. 989 * Reject them. 990 */ 991 switch (action) 992 { 993 case EC_F_COMPLETE: 994 case EC_B_COMPLETE: 995 case EC_EXPAND: 996 action = A_INVALID; 997 break; 998 } 999 } 1000#endif 1001 if ((flags & ECF_PEEK) || action == A_INVALID) 1002 { 1003 /* 1004 * We're just peeking, or we didn't understand the command. 1005 * Unget all the characters we read in the loop above. 1006 * This does NOT include the original character that was 1007 * passed in as a parameter. 1008 */ 1009 while (nch > 1) 1010 { 1011 ungetcc(usercmd[--nch]); 1012 } 1013 } else 1014 { 1015 if (s != NULL) 1016 ungetsc(s); 1017 } 1018 return action; 1019} 1020 1021