1 /* $NetBSD */ 2 3 /* 4 * Copyright (C) 1984-2011 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 about less, or for information on how to 10 * contact the author, see the README file. 11 */ 12 13 14 /* 15 * Prompting and other messages. 16 * There are three flavors of prompts, SHORT, MEDIUM and LONG, 17 * selected by the -m/-M options. 18 * There is also the "equals message", printed by the = command. 19 * A prompt is a message composed of various pieces, such as the 20 * name of the file being viewed, the percentage into the file, etc. 21 */ 22 23 #include "less.h" 24 #include "position.h" 25 26 extern int pr_type; 27 extern int new_file; 28 extern int sc_width; 29 extern int so_s_width, so_e_width; 30 extern int linenums; 31 extern int hshift; 32 extern int sc_height; 33 extern int jump_sline; 34 extern int less_is_more; 35 extern IFILE curr_ifile; 36 #if EDITOR 37 extern char *editor; 38 extern char *editproto; 39 #endif 40 41 /* 42 * Prototypes for the three flavors of prompts. 43 * These strings are expanded by pr_expand(). 44 */ 45 static constant char s_proto[] = 46 "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x..%t"; 47 static constant char m_proto[] = 48 "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t"; 49 static constant char M_proto[] = 50 "?f%f .?n?m(%T %i of %m) ..?ltlines %lt-%lb?L/%L. :byte %bB?s/%s. .?e(END) ?x- Next\\: %x.:?pB%pB\\%..%t"; 51 static constant char e_proto[] = 52 "?f%f .?m(%T %i of %m) .?ltlines %lt-%lb?L/%L. .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t"; 53 static constant char h_proto[] = 54 "HELP -- ?eEND -- Press g to see it again:Press RETURN for more., or q when done"; 55 static constant char w_proto[] = 56 "Waiting for data"; 57 static constant char more_proto[] = 58 "--More--(?eEND ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t)"; 59 60 public char *prproto[3]; 61 public char constant *eqproto = e_proto; 62 public char constant *hproto = h_proto; 63 public char constant *wproto = w_proto; 64 65 static char message[PROMPT_SIZE]; 66 static char *mp; 67 68 /* 69 * Initialize the prompt prototype strings. 70 */ 71 public void 72 init_prompt() 73 { 74 prproto[0] = save(s_proto); 75 prproto[1] = save(less_is_more ? more_proto : m_proto); 76 prproto[2] = save(M_proto); 77 eqproto = save(e_proto); 78 hproto = save(h_proto); 79 wproto = save(w_proto); 80 } 81 82 /* 83 * Append a string to the end of the message. 84 */ 85 static void 86 ap_str(s) 87 char *s; 88 { 89 int len; 90 91 len = strlen(s); 92 if (mp + len >= message + PROMPT_SIZE) 93 len = message + PROMPT_SIZE - mp - 1; 94 strncpy(mp, s, len); 95 mp += len; 96 *mp = '\0'; 97 } 98 99 /* 100 * Append a character to the end of the message. 101 */ 102 static void 103 ap_char(c) 104 char c; 105 { 106 char buf[2]; 107 108 buf[0] = c; 109 buf[1] = '\0'; 110 ap_str(buf); 111 } 112 113 /* 114 * Append a POSITION (as a decimal integer) to the end of the message. 115 */ 116 static void 117 ap_pos(pos) 118 POSITION pos; 119 { 120 char buf[INT_STRLEN_BOUND(pos) + 2]; 121 122 postoa(pos, buf); 123 ap_str(buf); 124 } 125 126 /* 127 * Append a line number to the end of the message. 128 */ 129 static void 130 ap_linenum(linenum) 131 LINENUM linenum; 132 { 133 char buf[INT_STRLEN_BOUND(linenum) + 2]; 134 135 linenumtoa(linenum, buf); 136 ap_str(buf); 137 } 138 139 /* 140 * Append an integer to the end of the message. 141 */ 142 static void 143 ap_int(num) 144 int num; 145 { 146 char buf[INT_STRLEN_BOUND(num) + 2]; 147 148 inttoa(num, buf); 149 ap_str(buf); 150 } 151 152 /* 153 * Append a question mark to the end of the message. 154 */ 155 static void 156 ap_quest() 157 { 158 ap_str("?"); 159 } 160 161 /* 162 * Return the "current" byte offset in the file. 163 */ 164 static POSITION 165 curr_byte(where) 166 int where; 167 { 168 POSITION pos; 169 170 pos = position(where); 171 while (pos == NULL_POSITION && where >= 0 && where < sc_height-1) 172 pos = position(++where); 173 if (pos == NULL_POSITION) 174 pos = ch_length(); 175 return (pos); 176 } 177 178 /* 179 * Return the value of a prototype conditional. 180 * A prototype string may include conditionals which consist of a 181 * question mark followed by a single letter. 182 * Here we decode that letter and return the appropriate boolean value. 183 */ 184 static int 185 cond(c, where) 186 char c; 187 int where; 188 { 189 POSITION len; 190 191 switch (c) 192 { 193 case 'a': /* Anything in the message yet? */ 194 return (mp > message); 195 case 'b': /* Current byte offset known? */ 196 return (curr_byte(where) != NULL_POSITION); 197 case 'c': 198 return (hshift != 0); 199 case 'e': /* At end of file? */ 200 return (eof_displayed()); 201 case 'f': /* Filename known? */ 202 return (strcmp(get_filename(curr_ifile), "-") != 0); 203 case 'l': /* Line number known? */ 204 case 'd': /* Same as l */ 205 return (linenums); 206 case 'L': /* Final line number known? */ 207 case 'D': /* Final page number known? */ 208 return (linenums && ch_length() != NULL_POSITION); 209 case 'm': /* More than one file? */ 210 #if TAGS 211 return (ntags() ? (ntags() > 1) : (nifile() > 1)); 212 #else 213 return (nifile() > 1); 214 #endif 215 case 'n': /* First prompt in a new file? */ 216 #if TAGS 217 return (ntags() ? 1 : new_file); 218 #else 219 return (new_file); 220 #endif 221 case 'p': /* Percent into file (bytes) known? */ 222 return (curr_byte(where) != NULL_POSITION && 223 ch_length() > 0); 224 case 'P': /* Percent into file (lines) known? */ 225 return (currline(where) != 0 && 226 (len = ch_length()) > 0 && 227 find_linenum(len) != 0); 228 case 's': /* Size of file known? */ 229 case 'B': 230 return (ch_length() != NULL_POSITION); 231 case 'x': /* Is there a "next" file? */ 232 #if TAGS 233 if (ntags()) 234 return (0); 235 #endif 236 return (next_ifile(curr_ifile) != NULL_IFILE); 237 } 238 return (0); 239 } 240 241 /* 242 * Decode a "percent" prototype character. 243 * A prototype string may include various "percent" escapes; 244 * that is, a percent sign followed by a single letter. 245 * Here we decode that letter and take the appropriate action, 246 * usually by appending something to the message being built. 247 */ 248 static void 249 protochar(c, where, iseditproto) 250 int c; 251 int where; 252 int iseditproto; 253 { 254 POSITION pos; 255 POSITION len; 256 int n; 257 LINENUM linenum; 258 LINENUM last_linenum; 259 IFILE h; 260 261 #undef PAGE_NUM 262 #define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - 1)) + 1) 263 264 switch (c) 265 { 266 case 'b': /* Current byte offset */ 267 pos = curr_byte(where); 268 if (pos != NULL_POSITION) 269 ap_pos(pos); 270 else 271 ap_quest(); 272 break; 273 case 'c': 274 ap_int(hshift); 275 break; 276 case 'd': /* Current page number */ 277 linenum = currline(where); 278 if (linenum > 0 && sc_height > 1) 279 ap_linenum(PAGE_NUM(linenum)); 280 else 281 ap_quest(); 282 break; 283 case 'D': /* Final page number */ 284 /* Find the page number of the last byte in the file (len-1). */ 285 len = ch_length(); 286 if (len == NULL_POSITION) 287 ap_quest(); 288 else if (len == 0) 289 /* An empty file has no pages. */ 290 ap_linenum(0); 291 else 292 { 293 linenum = find_linenum(len - 1); 294 if (linenum <= 0) 295 ap_quest(); 296 else 297 ap_linenum(PAGE_NUM(linenum)); 298 } 299 break; 300 #if EDITOR 301 case 'E': /* Editor name */ 302 ap_str(editor); 303 break; 304 #endif 305 case 'f': /* File name */ 306 ap_str(get_filename(curr_ifile)); 307 break; 308 case 'F': /* Last component of file name */ 309 ap_str(last_component(get_filename(curr_ifile))); 310 break; 311 case 'i': /* Index into list of files */ 312 #if TAGS 313 if (ntags()) 314 ap_int(curr_tag()); 315 else 316 #endif 317 ap_int(get_index(curr_ifile)); 318 break; 319 case 'l': /* Current line number */ 320 linenum = currline(where); 321 if (linenum != 0) 322 ap_linenum(linenum); 323 else 324 ap_quest(); 325 break; 326 case 'L': /* Final line number */ 327 len = ch_length(); 328 if (len == NULL_POSITION || len == ch_zero() || 329 (linenum = find_linenum(len)) <= 0) 330 ap_quest(); 331 else 332 ap_linenum(linenum-1); 333 break; 334 case 'm': /* Number of files */ 335 #if TAGS 336 n = ntags(); 337 if (n) 338 ap_int(n); 339 else 340 #endif 341 ap_int(nifile()); 342 break; 343 case 'p': /* Percent into file (bytes) */ 344 pos = curr_byte(where); 345 len = ch_length(); 346 if (pos != NULL_POSITION && len > 0) 347 ap_int(percentage(pos,len)); 348 else 349 ap_quest(); 350 break; 351 case 'P': /* Percent into file (lines) */ 352 linenum = currline(where); 353 if (linenum == 0 || 354 (len = ch_length()) == NULL_POSITION || len == ch_zero() || 355 (last_linenum = find_linenum(len)) <= 0) 356 ap_quest(); 357 else 358 ap_int(percentage(linenum, last_linenum)); 359 break; 360 case 's': /* Size of file */ 361 case 'B': 362 len = ch_length(); 363 if (len != NULL_POSITION) 364 ap_pos(len); 365 else 366 ap_quest(); 367 break; 368 case 't': /* Truncate trailing spaces in the message */ 369 while (mp > message && mp[-1] == ' ') 370 mp--; 371 *mp = '\0'; 372 break; 373 case 'T': /* Type of list */ 374 #if TAGS 375 if (ntags()) 376 ap_str("tag"); 377 else 378 #endif 379 ap_str("file"); 380 break; 381 case 'x': /* Name of next file */ 382 h = next_ifile(curr_ifile); 383 if (h != NULL_IFILE) 384 ap_str(get_filename(h)); 385 else 386 ap_quest(); 387 break; 388 } 389 } 390 391 /* 392 * Skip a false conditional. 393 * When a false condition is found (either a false IF or the ELSE part 394 * of a true IF), this routine scans the prototype string to decide 395 * where to resume parsing the string. 396 * We must keep track of nested IFs and skip them properly. 397 */ 398 static char * 399 skipcond(p) 400 register char *p; 401 { 402 register int iflevel; 403 404 /* 405 * We came in here after processing a ? or :, 406 * so we start nested one level deep. 407 */ 408 iflevel = 1; 409 410 for (;;) switch (*++p) 411 { 412 case '?': 413 /* 414 * Start of a nested IF. 415 */ 416 iflevel++; 417 break; 418 case ':': 419 /* 420 * Else. 421 * If this matches the IF we came in here with, 422 * then we're done. 423 */ 424 if (iflevel == 1) 425 return (p); 426 break; 427 case '.': 428 /* 429 * Endif. 430 * If this matches the IF we came in here with, 431 * then we're done. 432 */ 433 if (--iflevel == 0) 434 return (p); 435 break; 436 case '\\': 437 /* 438 * Backslash escapes the next character. 439 */ 440 ++p; 441 break; 442 case '\0': 443 /* 444 * Whoops. Hit end of string. 445 * This is a malformed conditional, but just treat it 446 * as if all active conditionals ends here. 447 */ 448 return (p-1); 449 } 450 /*NOTREACHED*/ 451 } 452 453 /* 454 * Decode a char that represents a position on the screen. 455 */ 456 static char * 457 wherechar(p, wp) 458 char *p; 459 int *wp; 460 { 461 switch (*p) 462 { 463 case 'b': case 'd': case 'l': case 'p': case 'P': 464 switch (*++p) 465 { 466 case 't': *wp = TOP; break; 467 case 'm': *wp = MIDDLE; break; 468 case 'b': *wp = BOTTOM; break; 469 case 'B': *wp = BOTTOM_PLUS_ONE; break; 470 case 'j': *wp = adjsline(jump_sline); break; 471 default: *wp = TOP; p--; break; 472 } 473 } 474 return (p); 475 } 476 477 /* 478 * Construct a message based on a prototype string. 479 */ 480 public char * 481 pr_expand(proto, maxwidth) 482 char *proto; 483 int maxwidth; 484 { 485 register char *p; 486 register int c; 487 int where; 488 489 mp = message; 490 491 if (*proto == '\0') 492 return (""); 493 494 for (p = proto; *p != '\0'; p++) 495 { 496 switch (*p) 497 { 498 default: /* Just put the character in the message */ 499 ap_char(*p); 500 break; 501 case '\\': /* Backslash escapes the next character */ 502 p++; 503 ap_char(*p); 504 break; 505 case '?': /* Conditional (IF) */ 506 if ((c = *++p) == '\0') 507 --p; 508 else 509 { 510 where = 0; 511 p = wherechar(p, &where); 512 if (!cond(c, where)) 513 p = skipcond(p); 514 } 515 break; 516 case ':': /* ELSE */ 517 p = skipcond(p); 518 break; 519 case '.': /* ENDIF */ 520 break; 521 case '%': /* Percent escape */ 522 if ((c = *++p) == '\0') 523 --p; 524 else 525 { 526 where = 0; 527 p = wherechar(p, &where); 528 protochar(c, where, 529 #if EDITOR 530 (proto == editproto)); 531 #else 532 0); 533 #endif 534 535 } 536 break; 537 } 538 } 539 540 if (mp == message) 541 return (""); 542 if (maxwidth > 0 && mp >= message + maxwidth) 543 { 544 /* 545 * Message is too long. 546 * Return just the final portion of it. 547 */ 548 return (mp - maxwidth); 549 } 550 return (message); 551 } 552 553 /* 554 * Return a message suitable for printing by the "=" command. 555 */ 556 public char * 557 eq_message() 558 { 559 return (pr_expand(eqproto, 0)); 560 } 561 562 /* 563 * Return a prompt. 564 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc. 565 * If we can't come up with an appropriate prompt, return NULL 566 * and the caller will prompt with a colon. 567 */ 568 public char * 569 pr_string() 570 { 571 char *prompt; 572 int type; 573 574 type = (!less_is_more) ? pr_type : pr_type ? 0 : 1; 575 prompt = pr_expand((ch_getflags() & CH_HELPFILE) ? 576 hproto : prproto[type], 577 sc_width-so_s_width-so_e_width-2); 578 new_file = 0; 579 return (prompt); 580 } 581 582 /* 583 * Return a message suitable for printing while waiting in the F command. 584 */ 585 public char * 586 wait_message() 587 { 588 return (pr_expand(wproto, sc_width-so_s_width-so_e_width-2)); 589 } 590