1 /* $NetBSD: decode.c,v 1.7 2023/10/06 07:13:13 simonb Exp $ */ 2 3 /* 4 * Copyright (C) 1984-2023 Mark Nudelman 5 * 6 * You may distribute under the terms of either the GNU General Public 7 * License or the Less License, as specified in the README file. 8 * 9 * For more information, see the README file. 10 */ 11 12 13 /* 14 * Routines to decode user commands. 15 * 16 * This is all table driven. 17 * A command table is a sequence of command descriptors. 18 * Each command descriptor is a sequence of bytes with the following format: 19 * <c1><c2>...<cN><0><action> 20 * The characters c1,c2,...,cN are the command string; that is, 21 * the characters which the user must type. 22 * It is terminated by a null <0> byte. 23 * The byte after the null byte is the action code associated 24 * with the command string. 25 * If an action byte is OR-ed with A_EXTRA, this indicates 26 * that the option byte is followed by an extra string. 27 * 28 * There may be many command tables. 29 * The first (default) table is built-in. 30 * Other tables are read in from "lesskey" files. 31 * All the tables are linked together and are searched in order. 32 */ 33 34 #include "less.h" 35 #include "cmd.h" 36 #include "lesskey.h" 37 38 extern int erase_char, erase2_char, kill_char; 39 extern int secure; 40 extern int mousecap; 41 extern int screen_trashed; 42 extern int sc_height; 43 44 #define SK(k) \ 45 SK_SPECIAL_KEY, (k), 6, 1, 1, 1 46 /* 47 * Command table is ordered roughly according to expected 48 * frequency of use, so the common commands are near the beginning. 49 */ 50 51 static unsigned char cmdtable[] = 52 { 53 '\r',0, A_F_LINE, 54 '\n',0, A_F_LINE, 55 'e',0, A_F_LINE, 56 'j',0, A_F_LINE, 57 SK(SK_DOWN_ARROW),0, A_F_LINE, 58 CONTROL('E'),0, A_F_LINE, 59 CONTROL('N'),0, A_F_LINE, 60 'k',0, A_B_LINE, 61 'y',0, A_B_LINE, 62 CONTROL('Y'),0, A_B_LINE, 63 SK(SK_CONTROL_K),0, A_B_LINE, 64 CONTROL('P'),0, A_B_LINE, 65 SK(SK_UP_ARROW),0, A_B_LINE, 66 'J',0, A_FF_LINE, 67 'K',0, A_BF_LINE, 68 'Y',0, A_BF_LINE, 69 'd',0, A_F_SCROLL, 70 CONTROL('D'),0, A_F_SCROLL, 71 'u',0, A_B_SCROLL, 72 CONTROL('U'),0, A_B_SCROLL, 73 ESC,'[','M',0, A_X11MOUSE_IN, 74 ESC,'[','<',0, A_X116MOUSE_IN, 75 ' ',0, A_F_SCREEN, 76 'f',0, A_F_SCREEN, 77 CONTROL('F'),0, A_F_SCREEN, 78 CONTROL('V'),0, A_F_SCREEN, 79 SK(SK_PAGE_DOWN),0, A_F_SCREEN, 80 'b',0, A_B_SCREEN, 81 CONTROL('B'),0, A_B_SCREEN, 82 ESC,'v',0, A_B_SCREEN, 83 SK(SK_PAGE_UP),0, A_B_SCREEN, 84 'z',0, A_F_WINDOW, 85 'w',0, A_B_WINDOW, 86 ESC,' ',0, A_FF_SCREEN, 87 'F',0, A_F_FOREVER, 88 ESC,'F',0, A_F_UNTIL_HILITE, 89 'R',0, A_FREPAINT, 90 'r',0, A_REPAINT, 91 CONTROL('R'),0, A_REPAINT, 92 CONTROL('L'),0, A_REPAINT, 93 ESC,'u',0, A_UNDO_SEARCH, 94 ESC,'U',0, A_CLR_SEARCH, 95 'g',0, A_GOLINE, 96 SK(SK_HOME),0, A_GOLINE, 97 '<',0, A_GOLINE, 98 ESC,'<',0, A_GOLINE, 99 'p',0, A_PERCENT, 100 '%',0, A_PERCENT, 101 ESC,'[',0, A_LSHIFT, 102 ESC,']',0, A_RSHIFT, 103 ESC,'(',0, A_LSHIFT, 104 ESC,')',0, A_RSHIFT, 105 ESC,'{',0, A_LLSHIFT, 106 ESC,'}',0, A_RRSHIFT, 107 SK(SK_RIGHT_ARROW),0, A_RSHIFT, 108 SK(SK_LEFT_ARROW),0, A_LSHIFT, 109 SK(SK_CTL_RIGHT_ARROW),0, A_RRSHIFT, 110 SK(SK_CTL_LEFT_ARROW),0, A_LLSHIFT, 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 '[',0, A_F_BRACKET|A_EXTRA, '[',']',0, 116 ']',0, A_B_BRACKET|A_EXTRA, '[',']',0, 117 ESC,CONTROL('F'),0, A_F_BRACKET, 118 ESC,CONTROL('B'),0, A_B_BRACKET, 119 'G',0, A_GOEND, 120 ESC,'G',0, A_GOEND_BUF, 121 ESC,'>',0, A_GOEND, 122 '>',0, A_GOEND, 123 SK(SK_END),0, A_GOEND, 124 'P',0, A_GOPOS, 125 126 '0',0, A_DIGIT, 127 '1',0, A_DIGIT, 128 '2',0, A_DIGIT, 129 '3',0, A_DIGIT, 130 '4',0, A_DIGIT, 131 '5',0, A_DIGIT, 132 '6',0, A_DIGIT, 133 '7',0, A_DIGIT, 134 '8',0, A_DIGIT, 135 '9',0, A_DIGIT, 136 '.',0, A_DIGIT, 137 138 '=',0, A_STAT, 139 CONTROL('G'),0, A_STAT, 140 ':','f',0, A_STAT, 141 '/',0, A_F_SEARCH, 142 '?',0, A_B_SEARCH, 143 ESC,'/',0, A_F_SEARCH|A_EXTRA, '*',0, 144 ESC,'?',0, A_B_SEARCH|A_EXTRA, '*',0, 145 'n',0, A_AGAIN_SEARCH, 146 ESC,'n',0, A_T_AGAIN_SEARCH, 147 'N',0, A_REVERSE_SEARCH, 148 ESC,'N',0, A_T_REVERSE_SEARCH, 149 '&',0, A_FILTER, 150 'm',0, A_SETMARK, 151 'M',0, A_SETMARKBOT, 152 ESC,'m',0, A_CLRMARK, 153 '\'',0, A_GOMARK, 154 CONTROL('X'),CONTROL('X'),0, A_GOMARK, 155 'E',0, A_EXAMINE, 156 ':','e',0, A_EXAMINE, 157 CONTROL('X'),CONTROL('V'),0, A_EXAMINE, 158 ':','n',0, A_NEXT_FILE, 159 ':','p',0, A_PREV_FILE, 160 't',0, A_NEXT_TAG, 161 'T',0, A_PREV_TAG, 162 ':','x',0, A_INDEX_FILE, 163 ':','d',0, A_REMOVE_FILE, 164 '-',0, A_OPT_TOGGLE, 165 ':','t',0, A_OPT_TOGGLE|A_EXTRA, 't',0, 166 's',0, A_OPT_TOGGLE|A_EXTRA, 'o',0, 167 '_',0, A_DISP_OPTION, 168 '|',0, A_PIPE, 169 'v',0, A_VISUAL, 170 '!',0, A_SHELL, 171 '#',0, A_PSHELL, 172 '+',0, A_FIRSTCMD, 173 174 'H',0, A_HELP, 175 'h',0, A_HELP, 176 SK(SK_F1),0, A_HELP, 177 'V',0, A_VERSION, 178 'q',0, A_QUIT, 179 'Q',0, A_QUIT, 180 ':','q',0, A_QUIT, 181 ':','Q',0, A_QUIT, 182 'Z','Z',0, A_QUIT 183 }; 184 185 static unsigned char edittable[] = 186 { 187 '\t',0, EC_F_COMPLETE, /* TAB */ 188 '\17',0, EC_B_COMPLETE, /* BACKTAB */ 189 SK(SK_BACKTAB),0, EC_B_COMPLETE, /* BACKTAB */ 190 ESC,'\t',0, EC_B_COMPLETE, /* ESC TAB */ 191 CONTROL('L'),0, EC_EXPAND, /* CTRL-L */ 192 CONTROL('V'),0, EC_LITERAL, /* BACKSLASH */ 193 CONTROL('A'),0, EC_LITERAL, /* BACKSLASH */ 194 ESC,'l',0, EC_RIGHT, /* ESC l */ 195 SK(SK_RIGHT_ARROW),0, EC_RIGHT, /* RIGHTARROW */ 196 ESC,'h',0, EC_LEFT, /* ESC h */ 197 SK(SK_LEFT_ARROW),0, EC_LEFT, /* LEFTARROW */ 198 ESC,'b',0, EC_W_LEFT, /* ESC b */ 199 ESC,SK(SK_LEFT_ARROW),0, EC_W_LEFT, /* ESC LEFTARROW */ 200 SK(SK_CTL_LEFT_ARROW),0, EC_W_LEFT, /* CTRL-LEFTARROW */ 201 ESC,'w',0, EC_W_RIGHT, /* ESC w */ 202 ESC,SK(SK_RIGHT_ARROW),0, EC_W_RIGHT, /* ESC RIGHTARROW */ 203 SK(SK_CTL_RIGHT_ARROW),0, EC_W_RIGHT, /* CTRL-RIGHTARROW */ 204 ESC,'i',0, EC_INSERT, /* ESC i */ 205 SK(SK_INSERT),0, EC_INSERT, /* INSERT */ 206 ESC,'x',0, EC_DELETE, /* ESC x */ 207 SK(SK_DELETE),0, EC_DELETE, /* DELETE */ 208 ESC,'X',0, EC_W_DELETE, /* ESC X */ 209 ESC,SK(SK_DELETE),0, EC_W_DELETE, /* ESC DELETE */ 210 SK(SK_CTL_DELETE),0, EC_W_DELETE, /* CTRL-DELETE */ 211 SK(SK_CTL_BACKSPACE),0, EC_W_BACKSPACE, /* CTRL-BACKSPACE */ 212 ESC,SK(SK_BACKSPACE),0, EC_W_BACKSPACE, /* ESC BACKSPACE */ 213 ESC,'0',0, EC_HOME, /* ESC 0 */ 214 SK(SK_HOME),0, EC_HOME, /* HOME */ 215 ESC,'$',0, EC_END, /* ESC $ */ 216 SK(SK_END),0, EC_END, /* END */ 217 ESC,'k',0, EC_UP, /* ESC k */ 218 SK(SK_UP_ARROW),0, EC_UP, /* UPARROW */ 219 ESC,'j',0, EC_DOWN, /* ESC j */ 220 SK(SK_DOWN_ARROW),0, EC_DOWN, /* DOWNARROW */ 221 CONTROL('G'),0, EC_ABORT, /* CTRL-G */ 222 ESC,'[','M',0, EC_X11MOUSE, /* X11 mouse report */ 223 ESC,'[','<',0, EC_X116MOUSE, /* X11 1006 mouse report */ 224 }; 225 226 /* 227 * Structure to support a list of command tables. 228 */ 229 struct tablelist 230 { 231 struct tablelist *t_next; 232 char *t_start; 233 char *t_end; 234 }; 235 236 /* 237 * List of command tables and list of line-edit tables. 238 */ 239 static struct tablelist *list_fcmd_tables = NULL; 240 static struct tablelist *list_ecmd_tables = NULL; 241 static struct tablelist *list_var_tables = NULL; 242 static struct tablelist *list_sysvar_tables = NULL; 243 244 245 /* 246 * Expand special key abbreviations in a command table. 247 */ 248 static void expand_special_keys(char *table, 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_* constants), 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 expand_cmd_table(struct tablelist *tlist) 307 { 308 struct tablelist *t; 309 for (t = tlist; t != NULL; t = t->t_next) 310 { 311 expand_special_keys(t->t_start, t->t_end - t->t_start); 312 } 313 } 314 315 /* 316 * Expand special key abbreviations in all command tables. 317 */ 318 public void expand_cmd_tables(void) 319 { 320 expand_cmd_table(list_fcmd_tables); 321 expand_cmd_table(list_ecmd_tables); 322 expand_cmd_table(list_var_tables); 323 expand_cmd_table(list_sysvar_tables); 324 } 325 326 327 /* 328 * Initialize the command lists. 329 */ 330 public void init_cmds(void) 331 { 332 /* 333 * Add the default command tables. 334 */ 335 add_fcmd_table((char*)cmdtable, sizeof(cmdtable)); 336 add_ecmd_table((char*)edittable, sizeof(edittable)); 337 #if USERFILE 338 #ifdef BINDIR /* For backwards compatibility */ 339 /* Try to add tables in the OLD system lesskey file. */ 340 add_hometable(lesskey, NULL, BINDIR "/.sysless", 1); 341 #endif 342 /* 343 * Try to load lesskey source file or binary file. 344 * If the source file succeeds, don't load binary file. 345 * The binary file is likely to have been generated from 346 * a (possibly out of date) copy of the src file, 347 * so loading it is at best redundant. 348 */ 349 /* 350 * Try to add tables in system lesskey src file. 351 */ 352 #if HAVE_LESSKEYSRC 353 if (add_hometable(lesskey_src, "LESSKEYIN_SYSTEM", LESSKEYINFILE_SYS, 1) != 0) 354 #endif 355 { 356 /* 357 * Try to add the tables in the system lesskey binary file. 358 */ 359 add_hometable(lesskey, "LESSKEY_SYSTEM", LESSKEYFILE_SYS, 1); 360 } 361 /* 362 * Try to add tables in the lesskey src file "$HOME/.lesskey". 363 */ 364 #if HAVE_LESSKEYSRC 365 if (add_hometable(lesskey_src, "LESSKEYIN", DEF_LESSKEYINFILE, 0) != 0) 366 #endif 367 { 368 /* 369 * Try to add the tables in the standard lesskey binary file "$HOME/.less". 370 */ 371 add_hometable(lesskey, "LESSKEY", LESSKEYFILE, 0); 372 } 373 #endif 374 } 375 376 /* 377 * Add a command table. 378 */ 379 static int add_cmd_table(struct tablelist **tlist, char *buf, int len) 380 { 381 struct tablelist *t; 382 383 if (len == 0) 384 return (0); 385 /* 386 * Allocate a tablelist structure, initialize it, 387 * and link it into the list of tables. 388 */ 389 if ((t = (struct tablelist *) 390 calloc(1, sizeof(struct tablelist))) == NULL) 391 { 392 return (-1); 393 } 394 t->t_start = buf; 395 t->t_end = buf + len; 396 t->t_next = *tlist; 397 *tlist = t; 398 return (0); 399 } 400 401 /* 402 * Add a command table. 403 */ 404 public void add_fcmd_table(char *buf, int len) 405 { 406 if (add_cmd_table(&list_fcmd_tables, buf, len) < 0) 407 error("Warning: some commands disabled", NULL_PARG); 408 } 409 410 /* 411 * Add an editing command table. 412 */ 413 public void add_ecmd_table(char *buf, int len) 414 { 415 if (add_cmd_table(&list_ecmd_tables, buf, len) < 0) 416 error("Warning: some edit commands disabled", NULL_PARG); 417 } 418 419 /* 420 * Add an environment variable table. 421 */ 422 static void add_var_table(struct tablelist **tlist, char *buf, int len) 423 { 424 if (add_cmd_table(tlist, buf, len) < 0) 425 error("Warning: environment variables from lesskey file unavailable", NULL_PARG); 426 } 427 428 /* 429 * Return action for a mouse wheel down event. 430 */ 431 static int mouse_wheel_down(void) 432 { 433 return ((mousecap == OPT_ONPLUS) ? A_B_MOUSE : A_F_MOUSE); 434 } 435 436 /* 437 * Return action for a mouse wheel up event. 438 */ 439 static int mouse_wheel_up(void) 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 mouse_button_rel(int x, int y) 448 { 449 /* 450 * {{ It would be better to return an action and then do this 451 * in commands() but it's nontrivial to pass y to it. }} 452 */ 453 if (y < sc_height-1) 454 { 455 setmark('#', y); 456 screen_trashed = 1; 457 } 458 return (A_NOACTION); 459 } 460 461 /* 462 * Read a decimal integer. Return the integer and set *pterm to the terminating char. 463 */ 464 static int getcc_int(char *pterm) 465 { 466 int num = 0; 467 int digits = 0; 468 for (;;) 469 { 470 char ch = getcc(); 471 if (ch < '0' || ch > '9') 472 { 473 if (pterm != NULL) *pterm = ch; 474 if (digits == 0) 475 return (-1); 476 return (num); 477 } 478 if (ckd_mul(&num, num, 10) || ckd_add(&num, num, ch - '0')) 479 return -1; 480 ++digits; 481 } 482 } 483 484 /* 485 * Read suffix of mouse input and return the action to take. 486 * The prefix ("\e[M") has already been read. 487 */ 488 static int x11mouse_action(int skip) 489 { 490 int b = getcc() - X11MOUSE_OFFSET; 491 int x = getcc() - X11MOUSE_OFFSET-1; 492 int y = getcc() - X11MOUSE_OFFSET-1; 493 if (skip) 494 return (A_NOACTION); 495 switch (b) { 496 default: 497 return (A_NOACTION); 498 case X11MOUSE_WHEEL_DOWN: 499 return mouse_wheel_down(); 500 case X11MOUSE_WHEEL_UP: 501 return mouse_wheel_up(); 502 case X11MOUSE_BUTTON_REL: 503 return mouse_button_rel(x, y); 504 } 505 } 506 507 /* 508 * Read suffix of mouse input and return the action to take. 509 * The prefix ("\e[<") has already been read. 510 */ 511 static int x116mouse_action(int skip) 512 { 513 char ch; 514 int x, y; 515 int b = getcc_int(&ch); 516 if (b < 0 || ch != ';') return (A_NOACTION); 517 x = getcc_int(&ch) - 1; 518 if (x < 0 || ch != ';') return (A_NOACTION); 519 y = getcc_int(&ch) - 1; 520 if (y < 0) return (A_NOACTION); 521 if (skip) 522 return (A_NOACTION); 523 switch (b) { 524 case X11MOUSE_WHEEL_DOWN: 525 return mouse_wheel_down(); 526 case X11MOUSE_WHEEL_UP: 527 return mouse_wheel_up(); 528 default: 529 if (ch != 'm') return (A_NOACTION); 530 return mouse_button_rel(x, y); 531 } 532 } 533 534 /* 535 * Search a single command table for the command string in cmd. 536 */ 537 static int cmd_search(char *cmd, char *table, char *endtable, char **sp) 538 { 539 char *p; 540 char *q; 541 int a; 542 543 *sp = NULL; 544 for (p = table, q = cmd; p < endtable; p++, q++) 545 { 546 if (*p == *q) 547 { 548 /* 549 * Current characters match. 550 * If we're at the end of the string, we've found it. 551 * Return the action code, which is the character 552 * after the null at the end of the string 553 * in the command table. 554 */ 555 if (*p == '\0') 556 { 557 a = *++p & 0377; 558 while (a == A_SKIP) 559 a = *++p & 0377; 560 if (a == A_END_LIST) 561 { 562 /* 563 * We get here only if the original 564 * cmd string passed in was empty (""). 565 * I don't think that can happen, 566 * but just in case ... 567 */ 568 return (A_UINVALID); 569 } 570 /* 571 * Check for an "extra" string. 572 */ 573 if (a & A_EXTRA) 574 { 575 *sp = ++p; 576 a &= ~A_EXTRA; 577 } 578 if (a == A_X11MOUSE_IN) 579 a = x11mouse_action(0); 580 else if (a == A_X116MOUSE_IN) 581 a = x116mouse_action(0); 582 return (a); 583 } 584 } else if (*q == '\0') 585 { 586 /* 587 * Hit the end of the user's command, 588 * but not the end of the string in the command table. 589 * The user's command is incomplete. 590 */ 591 return (A_PREFIX); 592 } else 593 { 594 /* 595 * Not a match. 596 * Skip ahead to the next command in the 597 * command table, and reset the pointer 598 * to the beginning of the user's command. 599 */ 600 if (*p == '\0' && p[1] == A_END_LIST) 601 { 602 /* 603 * A_END_LIST is a special marker that tells 604 * us to abort the cmd search. 605 */ 606 return (A_UINVALID); 607 } 608 while (*p++ != '\0') 609 continue; 610 while (*p == A_SKIP) 611 p++; 612 if (*p & A_EXTRA) 613 while (*++p != '\0') 614 continue; 615 q = cmd-1; 616 } 617 } 618 /* 619 * No match found in the entire command table. 620 */ 621 return (A_INVALID); 622 } 623 624 /* 625 * Decode a command character and return the associated action. 626 * The "extra" string, if any, is returned in sp. 627 */ 628 static int cmd_decode(struct tablelist *tlist, char *cmd, char **sp) 629 { 630 struct tablelist *t; 631 int action = A_INVALID; 632 633 /* 634 * Search thru all the command tables. 635 * Stop when we find an action which is not A_INVALID. 636 */ 637 for (t = tlist; t != NULL; t = t->t_next) 638 { 639 action = cmd_search(cmd, t->t_start, t->t_end, sp); 640 if (action != A_INVALID) 641 break; 642 } 643 if (action == A_UINVALID) 644 action = A_INVALID; 645 return (action); 646 } 647 648 /* 649 * Decode a command from the cmdtables list. 650 */ 651 public int fcmd_decode(char *cmd, char **sp) 652 { 653 return (cmd_decode(list_fcmd_tables, cmd, sp)); 654 } 655 656 /* 657 * Decode a command from the edittables list. 658 */ 659 public int ecmd_decode(char *cmd, char **sp) 660 { 661 return (cmd_decode(list_ecmd_tables, cmd, sp)); 662 } 663 664 /* 665 * Get the value of an environment variable. 666 * Looks first in the lesskey file, then in the real environment. 667 */ 668 public char * lgetenv(char *var) 669 { 670 int a; 671 char *s; 672 673 a = cmd_decode(list_var_tables, var, &s); 674 if (a == EV_OK) 675 return (s); 676 s = getenv(var); 677 if (s != NULL && *s != '\0') 678 return (s); 679 a = cmd_decode(list_sysvar_tables, var, &s); 680 if (a == EV_OK) 681 return (s); 682 return (NULL); 683 } 684 685 /* 686 * Is a string null or empty? 687 */ 688 public int isnullenv(char *s) 689 { 690 return (s == NULL || *s == '\0'); 691 } 692 693 #if USERFILE 694 /* 695 * Get an "integer" from a lesskey file. 696 * Integers are stored in a funny format: 697 * two bytes, low order first, in radix KRADIX. 698 */ 699 static int gint(char **sp) 700 { 701 int n; 702 703 n = *(*sp)++; 704 n += *(*sp)++ * KRADIX; 705 return (n); 706 } 707 708 /* 709 * Process an old (pre-v241) lesskey file. 710 */ 711 static int old_lesskey(char *buf, int len) 712 { 713 /* 714 * Old-style lesskey file. 715 * The file must end with either 716 * ...,cmd,0,action 717 * or ...,cmd,0,action|A_EXTRA,string,0 718 * So the last byte or the second to last byte must be zero. 719 */ 720 if (buf[len-1] != '\0' && buf[len-2] != '\0') 721 return (-1); 722 add_fcmd_table(buf, len); 723 return (0); 724 } 725 726 /* 727 * Process a new (post-v241) lesskey file. 728 */ 729 static int new_lesskey(char *buf, int len, int sysvar) 730 { 731 char *p; 732 char *end; 733 int c; 734 int n; 735 736 /* 737 * New-style lesskey file. 738 * Extract the pieces. 739 */ 740 if (buf[len-3] != C0_END_LESSKEY_MAGIC || 741 buf[len-2] != C1_END_LESSKEY_MAGIC || 742 buf[len-1] != C2_END_LESSKEY_MAGIC) 743 return (-1); 744 p = buf + 4; 745 end = buf + len; 746 for (;;) 747 { 748 c = *p++; 749 switch (c) 750 { 751 case CMD_SECTION: 752 n = gint(&p); 753 if (n < 0 || p+n >= end) 754 return (-1); 755 add_fcmd_table(p, n); 756 p += n; 757 break; 758 case EDIT_SECTION: 759 n = gint(&p); 760 if (n < 0 || p+n >= end) 761 return (-1); 762 add_ecmd_table(p, n); 763 p += n; 764 break; 765 case VAR_SECTION: 766 n = gint(&p); 767 if (n < 0 || p+n >= end) 768 return (-1); 769 add_var_table((sysvar) ? 770 &list_sysvar_tables : &list_var_tables, p, n); 771 p += n; 772 break; 773 case END_SECTION: 774 return (0); 775 default: 776 /* 777 * Unrecognized section type. 778 */ 779 return (-1); 780 } 781 } 782 } 783 784 /* 785 * Set up a user command table, based on a "lesskey" file. 786 */ 787 public int lesskey(char *filename, int sysvar) 788 { 789 char *buf; 790 POSITION len; 791 long n; 792 int f; 793 794 if (secure) 795 return (1); 796 /* 797 * Try to open the lesskey file. 798 */ 799 f = open(filename, OPEN_READ); 800 if (f < 0) 801 return (1); 802 803 /* 804 * Read the file into a buffer. 805 * We first figure out the size of the file and allocate space for it. 806 * {{ Minimal error checking is done here. 807 * A garbage .less file will produce strange results. 808 * To avoid a large amount of error checking code here, we 809 * rely on the lesskey program to generate a good .less file. }} 810 */ 811 len = filesize(f); 812 if (len == NULL_POSITION || len < 3) 813 { 814 /* 815 * Bad file (valid file must have at least 3 chars). 816 */ 817 close(f); 818 return (-1); 819 } 820 if ((buf = (char *) calloc((int)len, sizeof(char))) == NULL) 821 { 822 close(f); 823 return (-1); 824 } 825 if (lseek(f, (off_t)0, SEEK_SET) == BAD_LSEEK) 826 { 827 free(buf); 828 close(f); 829 return (-1); 830 } 831 n = read(f, buf, (unsigned int) len); 832 close(f); 833 if (n != len) 834 { 835 free(buf); 836 return (-1); 837 } 838 839 /* 840 * Figure out if this is an old-style (before version 241) 841 * or new-style lesskey file format. 842 */ 843 if (len < 4 || 844 buf[0] != C0_LESSKEY_MAGIC || buf[1] != C1_LESSKEY_MAGIC || 845 buf[2] != C2_LESSKEY_MAGIC || buf[3] != C3_LESSKEY_MAGIC) 846 return (old_lesskey(buf, (int)len)); 847 return (new_lesskey(buf, (int)len, sysvar)); 848 } 849 850 #if HAVE_LESSKEYSRC 851 public int lesskey_src(char *filename, int sysvar) 852 { 853 static struct lesskey_tables tables; 854 int r = parse_lesskey(filename, &tables); 855 if (r != 0) 856 return (r); 857 add_fcmd_table(xbuf_char_data(&tables.cmdtable.buf), tables.cmdtable.buf.end); 858 add_ecmd_table(xbuf_char_data(&tables.edittable.buf), tables.edittable.buf.end); 859 add_var_table(sysvar ? &list_sysvar_tables : &list_var_tables, 860 xbuf_char_data(&tables.vartable.buf), tables.vartable.buf.end); 861 return (0); 862 } 863 864 void lesskey_parse_error(char *s) 865 { 866 PARG parg; 867 parg.p_string = s; 868 error("%s", &parg); 869 } 870 #endif /* HAVE_LESSKEYSRC */ 871 872 /* 873 * Add a lesskey file. 874 */ 875 public int add_hometable(int (*call_lesskey)(char *, int), char *envname, char *def_filename, int sysvar) 876 { 877 char *filename; 878 int r; 879 880 if (envname != NULL && (filename = lgetenv(envname)) != NULL) 881 filename = save(filename); 882 else if (sysvar) /* def_filename is full path */ 883 filename = save(def_filename); 884 else /* def_filename is just basename */ 885 { 886 /* Remove first char (normally a dot) unless stored in $HOME. */ 887 char *xdg = lgetenv("XDG_CONFIG_HOME"); 888 if (!isnullenv(xdg)) 889 filename = dirfile(xdg, &def_filename[1], 1); 890 if (filename == NULL) 891 { 892 char *home = lgetenv("HOME"); 893 if (!isnullenv(home)) 894 { 895 char *cfg_dir = dirfile(home, ".config", 0); 896 filename = dirfile(cfg_dir, &def_filename[1], 1); 897 free(cfg_dir); 898 } 899 } 900 if (filename == NULL) 901 filename = homefile(def_filename); 902 } 903 if (filename == NULL) 904 return -1; 905 r = (*call_lesskey)(filename, sysvar); 906 free(filename); 907 return (r); 908 } 909 #endif 910 911 /* 912 * See if a char is a special line-editing command. 913 */ 914 public int editchar(int c, int flags) 915 { 916 int action; 917 int nch; 918 char *s; 919 char usercmd[MAX_CMDLEN+1]; 920 921 /* 922 * An editing character could actually be a sequence of characters; 923 * for example, an escape sequence sent by pressing the uparrow key. 924 * To match the editing string, we use the command decoder 925 * but give it the edit-commands command table 926 * This table is constructed to match the user's keyboard. 927 */ 928 if (c == erase_char || c == erase2_char) 929 return (EC_BACKSPACE); 930 if (c == kill_char) 931 { 932 #if MSDOS_COMPILER==WIN32C 933 if (!win32_kbhit()) 934 #endif 935 return (EC_LINEKILL); 936 } 937 938 /* 939 * Collect characters in a buffer. 940 * Start with the one we have, and get more if we need them. 941 */ 942 nch = 0; 943 do { 944 if (nch > 0) 945 c = getcc(); 946 usercmd[nch] = c; 947 usercmd[nch+1] = '\0'; 948 nch++; 949 action = ecmd_decode(usercmd, &s); 950 } while (action == A_PREFIX && nch < MAX_CMDLEN); 951 952 if (action == EC_X11MOUSE) 953 return (x11mouse_action(1)); 954 if (action == EC_X116MOUSE) 955 return (x116mouse_action(1)); 956 957 if (flags & ECF_NORIGHTLEFT) 958 { 959 switch (action) 960 { 961 case EC_RIGHT: 962 case EC_LEFT: 963 action = A_INVALID; 964 break; 965 } 966 } 967 #if CMD_HISTORY 968 if (flags & ECF_NOHISTORY) 969 { 970 /* 971 * The caller says there is no history list. 972 * Reject any history-manipulation action. 973 */ 974 switch (action) 975 { 976 case EC_UP: 977 case EC_DOWN: 978 action = A_INVALID; 979 break; 980 } 981 } 982 #endif 983 #if TAB_COMPLETE_FILENAME 984 if (flags & ECF_NOCOMPLETE) 985 { 986 /* 987 * The caller says we don't want any filename completion cmds. 988 * Reject them. 989 */ 990 switch (action) 991 { 992 case EC_F_COMPLETE: 993 case EC_B_COMPLETE: 994 case EC_EXPAND: 995 action = A_INVALID; 996 break; 997 } 998 } 999 #endif 1000 if ((flags & ECF_PEEK) || action == A_INVALID) 1001 { 1002 /* 1003 * We're just peeking, or we didn't understand the command. 1004 * Unget all the characters we read in the loop above. 1005 * This does NOT include the original character that was 1006 * passed in as a parameter. 1007 */ 1008 while (nch > 1) 1009 { 1010 ungetcc(usercmd[--nch]); 1011 } 1012 } else 1013 { 1014 if (s != NULL) 1015 ungetsc(s); 1016 } 1017 return action; 1018 } 1019 1020
Indexes created Tue Feb 24 08:35:24 UTC 2026