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 * The option table. 14 */ 15 16 #include "less.h" 17 #include "option.h" 18 19 /* 20 * Variables controlled by command line options. 21 */ 22 public int quiet; /* Should we suppress the audible bell? */ 23 public int how_search; /* Where should forward searches start? */ 24 public int top_scroll; /* Repaint screen from top? 25 (alternative is scroll from bottom) */ 26 public int pr_type; /* Type of prompt (short, medium, long) */ 27 public int bs_mode; /* How to process backspaces */ 28 public int know_dumb; /* Don't complain about dumb terminals */ 29 public int quit_at_eof; /* Quit after hitting end of file twice */ 30 public int quit_if_one_screen; /* Quit if EOF on first screen */ 31 public int squeeze; /* Squeeze multiple blank lines into one */ 32 public int tabstop; /* Tab settings */ 33 public int back_scroll; /* Repaint screen on backwards movement */ 34 public int forw_scroll; /* Repaint screen on forward movement */ 35 public int caseless; /* Do "caseless" searches */ 36 public int linenums; /* Use line numbers */ 37 public int autobuf; /* Automatically allocate buffers as needed */ 38 public int bufspace; /* Max buffer space per file (K) */ 39 public int ctldisp; /* Send control chars to screen untranslated */ 40 public int force_open; /* Open the file even if not regular file */ 41 public int swindow; /* Size of scrolling window */ 42 public int jump_sline; /* Screen line of "jump target" */ 43 public long jump_sline_fraction = -1; 44 public long shift_count_fraction = -1; 45 public int chopline; /* Truncate displayed lines at screen width */ 46 public int no_init; /* Disable sending ti/te termcap strings */ 47 public int no_keypad; /* Disable sending ks/ke termcap strings */ 48 public int twiddle; /* Show tildes after EOF */ 49 public int show_attn; /* Hilite first unread line */ 50 public int shift_count; /* Number of positions to shift horizontally */ 51 public int status_col; /* Display a status column */ 52 public int use_lessopen; /* Use the LESSOPEN filter */ 53 public int quit_on_intr; /* Quit on interrupt */ 54 public int follow_mode; /* F cmd Follows file desc or file name? */ 55 public int oldbot; /* Old bottom of screen behavior {{REMOVE}} */ 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 }; 119 120 121 /* 122 * Table of all options and their semantics. 123 * 124 * For BOOL and TRIPLE options, odesc[0], odesc[1], odesc[2] are 125 * the description of the option when set to 0, 1 or 2, respectively. 126 * For NUMBER options, odesc[0] is the prompt to use when entering 127 * a new value, and odesc[1] is the description, which should contain 128 * one %d which is replaced by the value of the number. 129 * For STRING options, odesc[0] is the prompt to use when entering 130 * a new value, and odesc[1], if not NULL, is the set of characters 131 * that are valid in the string. 132 */ 133 static struct loption option[] = 134 { 135 { 'a', &a_optname, 136 TRIPLE, OPT_ONPLUS, &how_search, NULL, 137 { 138 "Search includes displayed screen", 139 "Search skips displayed screen", 140 "Search includes all of displayed screen" 141 } 142 }, 143 144 { 'b', &b_optname, 145 NUMBER|INIT_HANDLER, 64, &bufspace, opt_b, 146 { 147 "Max buffer space per file (K): ", 148 "Max buffer space per file: %dK", 149 NULL 150 } 151 }, 152 { 'B', &B__optname, 153 BOOL, OPT_ON, &autobuf, NULL, 154 { 155 "Don't automatically allocate buffers", 156 "Automatically allocate buffers when needed", 157 NULL 158 } 159 }, 160 { 'c', &c_optname, 161 TRIPLE, OPT_OFF, &top_scroll, NULL, 162 { 163 "Repaint by scrolling from bottom of screen", 164 "Repaint by painting from top of screen", 165 "Repaint by painting from top of screen" 166 } 167 }, 168 { 'd', &d_optname, 169 BOOL|NO_TOGGLE, OPT_OFF, &know_dumb, NULL, 170 { 171 "Assume intelligent terminal", 172 "Assume dumb terminal", 173 NULL 174 } 175 }, 176 #if MSDOS_COMPILER 177 { 'D', &D__optname, 178 STRING|REPAINT|NO_QUERY, 0, NULL, opt_D, 179 { 180 "color desc: ", 181 "Ddknsu0123456789.", 182 NULL 183 } 184 }, 185 #endif 186 { 'e', &e_optname, 187 TRIPLE, OPT_OFF, &quit_at_eof, NULL, 188 { 189 "Don't quit at end-of-file", 190 "Quit at end-of-file", 191 "Quit immediately at end-of-file" 192 } 193 }, 194 { 'f', &f_optname, 195 BOOL, OPT_OFF, &force_open, NULL, 196 { 197 "Open only regular files", 198 "Open even non-regular files", 199 NULL 200 } 201 }, 202 { 'F', &F__optname, 203 BOOL, OPT_OFF, &quit_if_one_screen, NULL, 204 { 205 "Don't quit if end-of-file on first screen", 206 "Quit if end-of-file on first screen", 207 NULL 208 } 209 }, 210 #if HILITE_SEARCH 211 { 'g', &g_optname, 212 TRIPLE|HL_REPAINT, OPT_ONPLUS, &hilite_search, NULL, 213 { 214 "Don't highlight search matches", 215 "Highlight matches for previous search only", 216 "Highlight all matches for previous search pattern", 217 } 218 }, 219 #endif 220 { 'h', &h_optname, 221 NUMBER, -1, &back_scroll, NULL, 222 { 223 "Backwards scroll limit: ", 224 "Backwards scroll limit is %d lines", 225 NULL 226 } 227 }, 228 { 'i', &i_optname, 229 TRIPLE|HL_REPAINT, OPT_OFF, &caseless, opt_i, 230 { 231 "Case is significant in searches", 232 "Ignore case in searches", 233 "Ignore case in searches and in patterns" 234 } 235 }, 236 { 'j', &j_optname, 237 STRING, 0, NULL, opt_j, 238 { 239 "Target line: ", 240 "0123456789.-", 241 NULL 242 } 243 }, 244 { 'J', &J__optname, 245 BOOL|REPAINT, OPT_OFF, &status_col, NULL, 246 { 247 "Don't display a status column", 248 "Display a status column", 249 NULL 250 } 251 }, 252 #if USERFILE 253 { 'k', &k_optname, 254 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_k, 255 { NULL, NULL, NULL } 256 }, 257 #endif 258 { 'K', &K__optname, 259 BOOL, OPT_OFF, &quit_on_intr, NULL, 260 { 261 "Interrupt (ctrl-C) returns to prompt", 262 "Interrupt (ctrl-C) exits less", 263 NULL 264 } 265 }, 266 { 'l', NULL, 267 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_l, 268 { NULL, NULL, NULL } 269 }, 270 { 'L', &L__optname, 271 BOOL, OPT_ON, &use_lessopen, NULL, 272 { 273 "Don't use the LESSOPEN filter", 274 "Use the LESSOPEN filter", 275 NULL 276 } 277 }, 278 { 'm', &m_optname, 279 TRIPLE, OPT_OFF, &pr_type, NULL, 280 { 281 "Short prompt", 282 "Medium prompt", 283 "Long prompt" 284 } 285 }, 286 { 'n', &n_optname, 287 TRIPLE|REPAINT, OPT_ON, &linenums, NULL, 288 { 289 "Don't use line numbers", 290 "Use line numbers", 291 "Constantly display line numbers" 292 } 293 }, 294 #if LOGFILE 295 { 'o', &o_optname, 296 STRING, 0, NULL, opt_o, 297 { "log file: ", NULL, NULL } 298 }, 299 { 'O', &O__optname, 300 STRING, 0, NULL, opt__O, 301 { "Log file: ", NULL, NULL } 302 }, 303 #endif 304 { 'p', &p_optname, 305 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_p, 306 { NULL, NULL, NULL } 307 }, 308 { 'P', &P__optname, 309 STRING, 0, NULL, opt__P, 310 { "prompt: ", NULL, NULL } 311 }, 312 { 'q', &q_optname, 313 TRIPLE, OPT_OFF, &quiet, NULL, 314 { 315 "Ring the bell for errors AND at eof/bof", 316 "Ring the bell for errors but not at eof/bof", 317 "Never ring the bell" 318 } 319 }, 320 { 'r', &r_optname, 321 TRIPLE|REPAINT, OPT_OFF, &ctldisp, NULL, 322 { 323 "Display control characters as ^X", 324 "Display control characters directly", 325 "Display control characters directly, processing ANSI sequences" 326 } 327 }, 328 { 's', &s_optname, 329 BOOL|REPAINT, OPT_OFF, &squeeze, NULL, 330 { 331 "Display all blank lines", 332 "Squeeze multiple blank lines", 333 NULL 334 } 335 }, 336 { 'S', &S__optname, 337 BOOL|REPAINT, OPT_OFF, &chopline, NULL, 338 { 339 "Fold long lines", 340 "Chop long lines", 341 NULL 342 } 343 }, 344 #if TAGS 345 { 't', &t_optname, 346 STRING|NO_QUERY, 0, NULL, opt_t, 347 { "tag: ", NULL, NULL } 348 }, 349 { 'T', &T__optname, 350 STRING, 0, NULL, opt__T, 351 { "tags file: ", NULL, NULL } 352 }, 353 #endif 354 { 'u', &u_optname, 355 TRIPLE|REPAINT, OPT_OFF, &bs_mode, NULL, 356 { 357 "Display underlined text in underline mode", 358 "Backspaces cause overstrike", 359 "Print backspace as ^H" 360 } 361 }, 362 { 'V', &V__optname, 363 NOVAR, 0, NULL, opt__V, 364 { NULL, NULL, NULL } 365 }, 366 { 'w', &w_optname, 367 TRIPLE|REPAINT, OPT_OFF, &show_attn, NULL, 368 { 369 "Don't highlight first unread line", 370 "Highlight first unread line after forward-screen", 371 "Highlight first unread line after any forward movement", 372 } 373 }, 374 { 'x', &x_optname, 375 STRING|REPAINT, 0, NULL, opt_x, 376 { 377 "Tab stops: ", 378 "0123456789,", 379 NULL 380 } 381 }, 382 { 'X', &X__optname, 383 BOOL|NO_TOGGLE, OPT_OFF, &no_init, NULL, 384 { 385 "Send init/deinit strings to terminal", 386 "Don't use init/deinit strings", 387 NULL 388 } 389 }, 390 { 'y', &y_optname, 391 NUMBER, -1, &forw_scroll, NULL, 392 { 393 "Forward scroll limit: ", 394 "Forward scroll limit is %d lines", 395 NULL 396 } 397 }, 398 { 'z', &z_optname, 399 NUMBER, -1, &swindow, NULL, 400 { 401 "Scroll window size: ", 402 "Scroll window size is %d lines", 403 NULL 404 } 405 }, 406 { '"', "e_optname, 407 STRING, 0, NULL, opt_quote, 408 { "quotes: ", NULL, NULL } 409 }, 410 { '~', &tilde_optname, 411 BOOL|REPAINT, OPT_ON, &twiddle, NULL, 412 { 413 "Don't show tildes after end of file", 414 "Show tildes after end of file", 415 NULL 416 } 417 }, 418 { '?', &query_optname, 419 NOVAR, 0, NULL, opt_query, 420 { NULL, NULL, NULL } 421 }, 422 { '#', £_optname, 423 STRING, 0, NULL, opt_shift, 424 { 425 "Horizontal shift: ", 426 "0123456789.", 427 NULL 428 } 429 }, 430 { OLETTER_NONE, &keypad_optname, 431 BOOL|NO_TOGGLE, OPT_OFF, &no_keypad, NULL, 432 { 433 "Use keypad mode", 434 "Don't use keypad mode", 435 NULL 436 } 437 }, 438 { OLETTER_NONE, &oldbot_optname, 439 BOOL, OPT_OFF, &oldbot, NULL, 440 { 441 "Use new bottom of screen behavior", 442 "Use old bottom of screen behavior", 443 NULL 444 } 445 }, 446 { OLETTER_NONE, &follow_optname, 447 BOOL, FOLLOW_DESC, &follow_mode, NULL, 448 { 449 "F command follows file descriptor", 450 "F command follows file name", 451 NULL 452 } 453 }, 454 { '\0', NULL, NOVAR, 0, NULL, NULL, { NULL, NULL, NULL } } 455 }; 456 457 458 /* 459 * Initialize each option to its default value. 460 */ 461 public void 462 init_option() 463 { 464 register struct loption *o; 465 char *p; 466 467 p = lgetenv("LESS_IS_MORE"); 468 if (p != NULL && *p != '\0') 469 less_is_more = 1; 470 471 for (o = option; o->oletter != '\0'; o++) 472 { 473 /* 474 * Set each variable to its default. 475 */ 476 if (o->ovar != NULL) 477 *(o->ovar) = o->odefault; 478 if (o->otype & INIT_HANDLER) 479 (*(o->ofunc))(INIT, (char *) NULL); 480 } 481 } 482 483 /* 484 * Find an option in the option table, given its option letter. 485 */ 486 public struct loption * 487 findopt(c) 488 int c; 489 { 490 register struct loption *o; 491 492 for (o = option; o->oletter != '\0'; o++) 493 { 494 if (o->oletter == c) 495 return (o); 496 if ((o->otype & TRIPLE) && ASCII_TO_UPPER(o->oletter) == c) 497 return (o); 498 } 499 return (NULL); 500 } 501 502 /* 503 * 504 */ 505 static int 506 is_optchar(c) 507 char c; 508 { 509 if (ASCII_IS_UPPER(c)) 510 return 1; 511 if (ASCII_IS_LOWER(c)) 512 return 1; 513 if (c == '-') 514 return 1; 515 return 0; 516 } 517 518 /* 519 * Find an option in the option table, given its option name. 520 * p_optname is the (possibly partial) name to look for, and 521 * is updated to point after the matched name. 522 * p_oname if non-NULL is set to point to the full option name. 523 */ 524 public struct loption * 525 findopt_name(p_optname, p_oname, p_err) 526 char **p_optname; 527 char **p_oname; 528 int *p_err; 529 { 530 char *optname = *p_optname; 531 register struct loption *o; 532 register struct optname *oname; 533 register int len; 534 int uppercase; 535 struct loption *maxo = NULL; 536 struct optname *maxoname = NULL; 537 int maxlen = 0; 538 int ambig = 0; 539 int exact = 0; 540 541 /* 542 * Check all options. 543 */ 544 for (o = option; o->oletter != '\0'; o++) 545 { 546 /* 547 * Check all names for this option. 548 */ 549 for (oname = o->onames; oname != NULL; oname = oname->onext) 550 { 551 /* 552 * Try normal match first (uppercase == 0), 553 * then, then if it's a TRIPLE option, 554 * try uppercase match (uppercase == 1). 555 */ 556 for (uppercase = 0; uppercase <= 1; uppercase++) 557 { 558 len = sprefix(optname, oname->oname, uppercase); 559 if (len <= 0 || is_optchar(optname[len])) 560 { 561 /* 562 * We didn't use all of the option name. 563 */ 564 continue; 565 } 566 if (!exact && len == maxlen) 567 /* 568 * Already had a partial match, 569 * and now there's another one that 570 * matches the same length. 571 */ 572 ambig = 1; 573 else if (len > maxlen) 574 { 575 /* 576 * Found a better match than 577 * the one we had. 578 */ 579 maxo = o; 580 maxoname = oname; 581 maxlen = len; 582 ambig = 0; 583 exact = (len == (int)strlen(oname->oname)); 584 } 585 if (!(o->otype & TRIPLE)) 586 break; 587 } 588 } 589 } 590 if (ambig) 591 { 592 /* 593 * Name matched more than one option. 594 */ 595 if (p_err != NULL) 596 *p_err = OPT_AMBIG; 597 return (NULL); 598 } 599 *p_optname = optname + maxlen; 600 if (p_oname != NULL) 601 *p_oname = maxoname == NULL ? NULL : maxoname->oname; 602 return (maxo); 603 } 604