1 /* 2 * Copyright (C) 1984-2017 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 * The option table. 13 */ 14 15 #include "less.h" 16 #include "option.h" 17 18 /* 19 * Variables controlled by command line options. 20 */ 21 public int quiet; /* Should we suppress the audible bell? */ 22 public int how_search; /* Where should forward searches start? */ 23 public int top_scroll; /* Repaint screen from top? 24 (alternative is scroll from bottom) */ 25 public int pr_type; /* Type of prompt (short, medium, long) */ 26 public int bs_mode; /* How to process backspaces */ 27 public int know_dumb; /* Don't complain about dumb terminals */ 28 public int quit_at_eof; /* Quit after hitting end of file twice */ 29 public int quit_if_one_screen; /* Quit if EOF on first screen */ 30 public int squeeze; /* Squeeze multiple blank lines into one */ 31 public int tabstop; /* Tab settings */ 32 public int back_scroll; /* Repaint screen on backwards movement */ 33 public int forw_scroll; /* Repaint screen on forward movement */ 34 public int caseless; /* Do "caseless" searches */ 35 public int linenums; /* Use line numbers */ 36 public int autobuf; /* Automatically allocate buffers as needed */ 37 public int bufspace; /* Max buffer space per file (K) */ 38 public int ctldisp; /* Send control chars to screen untranslated */ 39 public int force_open; /* Open the file even if not regular file */ 40 public int swindow; /* Size of scrolling window */ 41 public int jump_sline; /* Screen line of "jump target" */ 42 public long jump_sline_fraction = -1; 43 public long shift_count_fraction = -1; 44 public int chopline; /* Truncate displayed lines at screen width */ 45 public int no_init; /* Disable sending ti/te termcap strings */ 46 public int no_keypad; /* Disable sending ks/ke termcap strings */ 47 public int twiddle; /* Show tildes after EOF */ 48 public int show_attn; /* Hilite first unread line */ 49 public int shift_count; /* Number of positions to shift horizontally */ 50 public int status_col; /* Display a status column */ 51 public int use_lessopen; /* Use the LESSOPEN filter */ 52 public int quit_on_intr; /* Quit on interrupt */ 53 public int follow_mode; /* F cmd Follows file desc or file name? */ 54 public int oldbot; /* Old bottom of screen behavior {{REMOVE}} */ 55 public int opt_use_backslash; /* Use backslash escaping in option parsing */ 56 #if HILITE_SEARCH 57 public int hilite_search; /* Highlight matched search patterns? */ 58 #endif 59 60 public int less_is_more = 0; /* Make compatible with POSIX more */ 61 62 /* 63 * Long option names. 64 */ 65 static struct optname a_optname = { "search-skip-screen", NULL }; 66 static struct optname b_optname = { "buffers", NULL }; 67 static struct optname B__optname = { "auto-buffers", NULL }; 68 static struct optname c_optname = { "clear-screen", NULL }; 69 static struct optname d_optname = { "dumb", NULL }; 70 #if MSDOS_COMPILER 71 static struct optname D__optname = { "color", NULL }; 72 #endif 73 static struct optname e_optname = { "quit-at-eof", NULL }; 74 static struct optname f_optname = { "force", NULL }; 75 static struct optname F__optname = { "quit-if-one-screen", NULL }; 76 #if HILITE_SEARCH 77 static struct optname g_optname = { "hilite-search", NULL }; 78 #endif 79 static struct optname h_optname = { "max-back-scroll", NULL }; 80 static struct optname i_optname = { "ignore-case", NULL }; 81 static struct optname j_optname = { "jump-target", NULL }; 82 static struct optname J__optname = { "status-column", NULL }; 83 #if USERFILE 84 static struct optname k_optname = { "lesskey-file", NULL }; 85 #endif 86 static struct optname K__optname = { "quit-on-intr", NULL }; 87 static struct optname L__optname = { "no-lessopen", NULL }; 88 static struct optname m_optname = { "long-prompt", NULL }; 89 static struct optname n_optname = { "line-numbers", NULL }; 90 #if LOGFILE 91 static struct optname o_optname = { "log-file", NULL }; 92 static struct optname O__optname = { "LOG-FILE", NULL }; 93 #endif 94 static struct optname p_optname = { "pattern", NULL }; 95 static struct optname P__optname = { "prompt", NULL }; 96 static struct optname q2_optname = { "silent", NULL }; 97 static struct optname q_optname = { "quiet", &q2_optname }; 98 static struct optname r_optname = { "raw-control-chars", NULL }; 99 static struct optname s_optname = { "squeeze-blank-lines", NULL }; 100 static struct optname S__optname = { "chop-long-lines", NULL }; 101 #if TAGS 102 static struct optname t_optname = { "tag", NULL }; 103 static struct optname T__optname = { "tag-file", NULL }; 104 #endif 105 static struct optname u_optname = { "underline-special", NULL }; 106 static struct optname V__optname = { "version", NULL }; 107 static struct optname w_optname = { "hilite-unread", NULL }; 108 static struct optname x_optname = { "tabs", NULL }; 109 static struct optname X__optname = { "no-init", NULL }; 110 static struct optname y_optname = { "max-forw-scroll", NULL }; 111 static struct optname z_optname = { "window", NULL }; 112 static struct optname quote_optname = { "quotes", NULL }; 113 static struct optname tilde_optname = { "tilde", NULL }; 114 static struct optname query_optname = { "help", NULL }; 115 static struct optname pound_optname = { "shift", NULL }; 116 static struct optname keypad_optname = { "no-keypad", NULL }; 117 static struct optname oldbot_optname = { "old-bot", NULL }; 118 static struct optname follow_optname = { "follow-name", NULL }; 119 static struct optname use_backslash_optname = { "use-backslash", NULL }; 120 121 122 /* 123 * Table of all options and their semantics. 124 * 125 * For BOOL and TRIPLE options, odesc[0], odesc[1], odesc[2] are 126 * the description of the option when set to 0, 1 or 2, respectively. 127 * For NUMBER options, odesc[0] is the prompt to use when entering 128 * a new value, and odesc[1] is the description, which should contain 129 * one %d which is replaced by the value of the number. 130 * For STRING options, odesc[0] is the prompt to use when entering 131 * a new value, and odesc[1], if not NULL, is the set of characters 132 * that are valid in the string. 133 */ 134 static struct loption option[] = 135 { 136 { 'a', &a_optname, 137 TRIPLE, OPT_ONPLUS, &how_search, NULL, 138 { 139 "Search includes displayed screen", 140 "Search skips displayed screen", 141 "Search includes all of displayed screen" 142 } 143 }, 144 145 { 'b', &b_optname, 146 NUMBER|INIT_HANDLER, 64, &bufspace, opt_b, 147 { 148 "Max buffer space per file (K): ", 149 "Max buffer space per file: %dK", 150 NULL 151 } 152 }, 153 { 'B', &B__optname, 154 BOOL, OPT_ON, &autobuf, NULL, 155 { 156 "Don't automatically allocate buffers", 157 "Automatically allocate buffers when needed", 158 NULL 159 } 160 }, 161 { 'c', &c_optname, 162 TRIPLE, OPT_OFF, &top_scroll, NULL, 163 { 164 "Repaint by scrolling from bottom of screen", 165 "Repaint by painting from top of screen", 166 "Repaint by painting from top of screen" 167 } 168 }, 169 { 'd', &d_optname, 170 BOOL|NO_TOGGLE, OPT_OFF, &know_dumb, NULL, 171 { 172 "Assume intelligent terminal", 173 "Assume dumb terminal", 174 NULL 175 } 176 }, 177 #if MSDOS_COMPILER 178 { 'D', &D__optname, 179 STRING|REPAINT, 0, NULL, opt_D, 180 { 181 "color desc: ", 182 "Dadknsu0123456789.", 183 NULL 184 } 185 }, 186 #endif 187 { 'e', &e_optname, 188 TRIPLE, OPT_OFF, &quit_at_eof, NULL, 189 { 190 "Don't quit at end-of-file", 191 "Quit at end-of-file", 192 "Quit immediately at end-of-file" 193 } 194 }, 195 { 'f', &f_optname, 196 BOOL, OPT_OFF, &force_open, NULL, 197 { 198 "Open only regular files", 199 "Open even non-regular files", 200 NULL 201 } 202 }, 203 { 'F', &F__optname, 204 BOOL, OPT_OFF, &quit_if_one_screen, NULL, 205 { 206 "Don't quit if end-of-file on first screen", 207 "Quit if end-of-file on first screen", 208 NULL 209 } 210 }, 211 #if HILITE_SEARCH 212 { 'g', &g_optname, 213 TRIPLE|HL_REPAINT, OPT_ONPLUS, &hilite_search, NULL, 214 { 215 "Don't highlight search matches", 216 "Highlight matches for previous search only", 217 "Highlight all matches for previous search pattern", 218 } 219 }, 220 #endif 221 { 'h', &h_optname, 222 NUMBER, -1, &back_scroll, NULL, 223 { 224 "Backwards scroll limit: ", 225 "Backwards scroll limit is %d lines", 226 NULL 227 } 228 }, 229 { 'i', &i_optname, 230 TRIPLE|HL_REPAINT, OPT_OFF, &caseless, opt_i, 231 { 232 "Case is significant in searches", 233 "Ignore case in searches", 234 "Ignore case in searches and in patterns" 235 } 236 }, 237 { 'j', &j_optname, 238 STRING, 0, NULL, opt_j, 239 { 240 "Target line: ", 241 "0123456789.-", 242 NULL 243 } 244 }, 245 { 'J', &J__optname, 246 BOOL|REPAINT, OPT_OFF, &status_col, NULL, 247 { 248 "Don't display a status column", 249 "Display a status column", 250 NULL 251 } 252 }, 253 #if USERFILE 254 { 'k', &k_optname, 255 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_k, 256 { NULL, NULL, NULL } 257 }, 258 #endif 259 { 'K', &K__optname, 260 BOOL, OPT_OFF, &quit_on_intr, NULL, 261 { 262 "Interrupt (ctrl-C) returns to prompt", 263 "Interrupt (ctrl-C) exits less", 264 NULL 265 } 266 }, 267 { 'L', &L__optname, 268 BOOL, OPT_ON, &use_lessopen, NULL, 269 { 270 "Don't use the LESSOPEN filter", 271 "Use the LESSOPEN filter", 272 NULL 273 } 274 }, 275 { 'm', &m_optname, 276 TRIPLE, OPT_OFF, &pr_type, NULL, 277 { 278 "Short prompt", 279 "Medium prompt", 280 "Long prompt" 281 } 282 }, 283 { 'n', &n_optname, 284 TRIPLE|REPAINT, OPT_ON, &linenums, NULL, 285 { 286 "Don't use line numbers", 287 "Use line numbers", 288 "Constantly display line numbers" 289 } 290 }, 291 #if LOGFILE 292 { 'o', &o_optname, 293 STRING, 0, NULL, opt_o, 294 { "log file: ", NULL, NULL } 295 }, 296 { 'O', &O__optname, 297 STRING, 0, NULL, opt__O, 298 { "Log file: ", NULL, NULL } 299 }, 300 #endif 301 { 'p', &p_optname, 302 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_p, 303 { NULL, NULL, NULL } 304 }, 305 { 'P', &P__optname, 306 STRING, 0, NULL, opt__P, 307 { "prompt: ", NULL, NULL } 308 }, 309 { 'q', &q_optname, 310 TRIPLE, OPT_OFF, &quiet, NULL, 311 { 312 "Ring the bell for errors AND at eof/bof", 313 "Ring the bell for errors but not at eof/bof", 314 "Never ring the bell" 315 } 316 }, 317 { 'r', &r_optname, 318 TRIPLE|REPAINT, OPT_OFF, &ctldisp, NULL, 319 { 320 "Display control characters as ^X", 321 "Display control characters directly", 322 "Display control characters directly, processing ANSI sequences" 323 } 324 }, 325 { 's', &s_optname, 326 BOOL|REPAINT, OPT_OFF, &squeeze, NULL, 327 { 328 "Display all blank lines", 329 "Squeeze multiple blank lines", 330 NULL 331 } 332 }, 333 { 'S', &S__optname, 334 BOOL|REPAINT, OPT_OFF, &chopline, NULL, 335 { 336 "Fold long lines", 337 "Chop long lines", 338 NULL 339 } 340 }, 341 #if TAGS 342 { 't', &t_optname, 343 STRING|NO_QUERY, 0, NULL, opt_t, 344 { "tag: ", NULL, NULL } 345 }, 346 { 'T', &T__optname, 347 STRING, 0, NULL, opt__T, 348 { "tags file: ", NULL, NULL } 349 }, 350 #endif 351 { 'u', &u_optname, 352 TRIPLE|REPAINT, OPT_OFF, &bs_mode, NULL, 353 { 354 "Display underlined text in underline mode", 355 "Backspaces cause overstrike", 356 "Print backspace as ^H" 357 } 358 }, 359 { 'V', &V__optname, 360 NOVAR, 0, NULL, opt__V, 361 { NULL, NULL, NULL } 362 }, 363 { 'w', &w_optname, 364 TRIPLE|REPAINT, OPT_OFF, &show_attn, NULL, 365 { 366 "Don't highlight first unread line", 367 "Highlight first unread line after forward-screen", 368 "Highlight first unread line after any forward movement", 369 } 370 }, 371 { 'x', &x_optname, 372 STRING|REPAINT, 0, NULL, opt_x, 373 { 374 "Tab stops: ", 375 "0123456789,", 376 NULL 377 } 378 }, 379 { 'X', &X__optname, 380 BOOL|NO_TOGGLE, OPT_OFF, &no_init, NULL, 381 { 382 "Send init/deinit strings to terminal", 383 "Don't use init/deinit strings", 384 NULL 385 } 386 }, 387 { 'y', &y_optname, 388 NUMBER, -1, &forw_scroll, NULL, 389 { 390 "Forward scroll limit: ", 391 "Forward scroll limit is %d lines", 392 NULL 393 } 394 }, 395 { 'z', &z_optname, 396 NUMBER, -1, &swindow, NULL, 397 { 398 "Scroll window size: ", 399 "Scroll window size is %d lines", 400 NULL 401 } 402 }, 403 { '"', "e_optname, 404 STRING, 0, NULL, opt_quote, 405 { "quotes: ", NULL, NULL } 406 }, 407 { '~', &tilde_optname, 408 BOOL|REPAINT, OPT_ON, &twiddle, NULL, 409 { 410 "Don't show tildes after end of file", 411 "Show tildes after end of file", 412 NULL 413 } 414 }, 415 { '?', &query_optname, 416 NOVAR, 0, NULL, opt_query, 417 { NULL, NULL, NULL } 418 }, 419 { '#', £_optname, 420 STRING, 0, NULL, opt_shift, 421 { 422 "Horizontal shift: ", 423 "0123456789.", 424 NULL 425 } 426 }, 427 { OLETTER_NONE, &keypad_optname, 428 BOOL|NO_TOGGLE, OPT_OFF, &no_keypad, NULL, 429 { 430 "Use keypad mode", 431 "Don't use keypad mode", 432 NULL 433 } 434 }, 435 { OLETTER_NONE, &oldbot_optname, 436 BOOL, OPT_OFF, &oldbot, NULL, 437 { 438 "Use new bottom of screen behavior", 439 "Use old bottom of screen behavior", 440 NULL 441 } 442 }, 443 { OLETTER_NONE, &follow_optname, 444 BOOL, FOLLOW_DESC, &follow_mode, NULL, 445 { 446 "F command follows file descriptor", 447 "F command follows file name", 448 NULL 449 } 450 }, 451 { OLETTER_NONE, &use_backslash_optname, 452 BOOL, OPT_OFF, &opt_use_backslash, NULL, 453 { 454 "Use backslash escaping in command line parameters", 455 "Don't use backslash escaping in command line parameters", 456 NULL 457 } 458 }, 459 { '\0', NULL, NOVAR, 0, NULL, NULL, { NULL, NULL, NULL } } 460 }; 461 462 463 /* 464 * Initialize each option to its default value. 465 */ 466 public void 467 init_option() 468 { 469 struct loption *o; 470 char *p; 471 472 p = lgetenv("LESS_IS_MORE"); 473 if (p != NULL && *p != '\0') 474 less_is_more = 1; 475 476 for (o = option; o->oletter != '\0'; o++) 477 { 478 /* 479 * Set each variable to its default. 480 */ 481 if (o->ovar != NULL) 482 *(o->ovar) = o->odefault; 483 if (o->otype & INIT_HANDLER) 484 (*(o->ofunc))(INIT, (char *) NULL); 485 } 486 } 487 488 /* 489 * Find an option in the option table, given its option letter. 490 */ 491 public struct loption * 492 findopt(c) 493 int c; 494 { 495 struct loption *o; 496 497 for (o = option; o->oletter != '\0'; o++) 498 { 499 if (o->oletter == c) 500 return (o); 501 if ((o->otype & TRIPLE) && ASCII_TO_UPPER(o->oletter) == c) 502 return (o); 503 } 504 return (NULL); 505 } 506 507 /* 508 * 509 */ 510 static int 511 is_optchar(c) 512 char c; 513 { 514 if (ASCII_IS_UPPER(c)) 515 return 1; 516 if (ASCII_IS_LOWER(c)) 517 return 1; 518 if (c == '-') 519 return 1; 520 return 0; 521 } 522 523 /* 524 * Find an option in the option table, given its option name. 525 * p_optname is the (possibly partial) name to look for, and 526 * is updated to point after the matched name. 527 * p_oname if non-NULL is set to point to the full option name. 528 */ 529 public struct loption * 530 findopt_name(p_optname, p_oname, p_err) 531 char **p_optname; 532 char **p_oname; 533 int *p_err; 534 { 535 char *optname = *p_optname; 536 struct loption *o; 537 struct optname *oname; 538 int len; 539 int uppercase; 540 struct loption *maxo = NULL; 541 struct optname *maxoname = NULL; 542 int maxlen = 0; 543 int ambig = 0; 544 int exact = 0; 545 546 /* 547 * Check all options. 548 */ 549 for (o = option; o->oletter != '\0'; o++) 550 { 551 /* 552 * Check all names for this option. 553 */ 554 for (oname = o->onames; oname != NULL; oname = oname->onext) 555 { 556 /* 557 * Try normal match first (uppercase == 0), 558 * then, then if it's a TRIPLE option, 559 * try uppercase match (uppercase == 1). 560 */ 561 for (uppercase = 0; uppercase <= 1; uppercase++) 562 { 563 len = sprefix(optname, oname->oname, uppercase); 564 if (len <= 0 || is_optchar(optname[len])) 565 { 566 /* 567 * We didn't use all of the option name. 568 */ 569 continue; 570 } 571 if (!exact && len == maxlen) 572 /* 573 * Already had a partial match, 574 * and now there's another one that 575 * matches the same length. 576 */ 577 ambig = 1; 578 else if (len > maxlen) 579 { 580 /* 581 * Found a better match than 582 * the one we had. 583 */ 584 maxo = o; 585 maxoname = oname; 586 maxlen = len; 587 ambig = 0; 588 exact = (len == (int)strlen(oname->oname)); 589 } 590 if (!(o->otype & TRIPLE)) 591 break; 592 } 593 } 594 } 595 if (ambig) 596 { 597 /* 598 * Name matched more than one option. 599 */ 600 if (p_err != NULL) 601 *p_err = OPT_AMBIG; 602 return (NULL); 603 } 604 *p_optname = optname + maxlen; 605 if (p_oname != NULL) 606 *p_oname = maxoname == NULL ? NULL : maxoname->oname; 607 return (maxo); 608 } 609