1 /* 2 * Copyright (C) 1984-2025 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 * Prompting and other messages. 13 * There are three flavors of prompts, SHORT, MEDIUM and LONG, 14 * selected by the -m/-M options. 15 * There is also the "equals message", printed by the = command. 16 * A prompt is a message composed of various pieces, such as the 17 * name of the file being viewed, the percentage into the file, etc. 18 */ 19 20 #include "less.h" 21 #include "position.h" 22 23 extern int pr_type; 24 extern lbool new_file; 25 extern int linenums; 26 extern int hshift; 27 extern int sc_height; 28 extern int jump_sline; 29 extern int less_is_more; 30 extern int header_lines; 31 extern int utf_mode; 32 extern IFILE curr_ifile; 33 #if OSC8_LINK 34 extern char *osc8_path; 35 #endif 36 #if EDITOR 37 extern constant char *editor; 38 extern constant 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 init_prompt(void) 72 { 73 prproto[0] = save(s_proto); 74 prproto[1] = save(less_is_more ? more_proto : m_proto); 75 prproto[2] = save(M_proto); 76 eqproto = save(e_proto); 77 hproto = save(h_proto); 78 wproto = save(w_proto); 79 } 80 81 /* 82 * Append a string to the end of the message. 83 * nprt means the character *may* be nonprintable 84 * and should be converted to printable form. 85 */ 86 static void ap_estr(constant char *s, lbool nprt) 87 { 88 constant char *es = s + strlen(s); 89 while (*s != '\0') 90 { 91 LWCHAR ch = step_charc(&s, +1, es); 92 constant char *ps; 93 char ubuf[MAX_UTF_CHAR_LEN+1]; 94 size_t plen; 95 96 if (nprt) 97 { 98 ps = utf_mode ? prutfchar(ch) : prchar(ch); 99 } else 100 { 101 char *up = ubuf; 102 put_wchar(&up, ch); 103 *up = '\0'; 104 ps = ubuf; 105 } 106 plen = strlen(ps); 107 if (mp + plen >= message + PROMPT_SIZE) 108 break; 109 strcpy(mp, ps); 110 mp += plen; 111 } 112 *mp = '\0'; 113 } 114 115 static void ap_str(constant char *s) 116 { 117 ap_estr(s, FALSE); 118 } 119 120 /* 121 * Append a character to the end of the message. 122 */ 123 static void ap_char(char c) 124 { 125 if (mp + 1 >= message + PROMPT_SIZE) 126 return; 127 *mp++ = c; 128 *mp = '\0'; 129 } 130 131 /* 132 * Append a POSITION (as a decimal integer) to the end of the message. 133 */ 134 static void ap_pos(POSITION pos) 135 { 136 char buf[INT_STRLEN_BOUND(pos) + 2]; 137 138 postoa(pos, buf, 10); 139 ap_str(buf); 140 } 141 142 /* 143 * Append a line number to the end of the message. 144 */ 145 static void ap_linenum(LINENUM linenum) 146 { 147 char buf[INT_STRLEN_BOUND(linenum) + 2]; 148 149 linenumtoa(linenum, buf, 10); 150 ap_str(buf); 151 } 152 153 /* 154 * Append an integer to the end of the message. 155 */ 156 static void ap_int(int num) 157 { 158 char buf[INT_STRLEN_BOUND(num) + 2]; 159 160 inttoa(num, buf, 10); 161 ap_str(buf); 162 } 163 164 /* 165 * Append a question mark to the end of the message. 166 */ 167 static void ap_quest(void) 168 { 169 ap_str("?"); 170 } 171 172 /* 173 * Return the "current" byte offset in the file. 174 */ 175 static POSITION curr_byte(int where) 176 { 177 POSITION pos; 178 179 pos = position(where); 180 while (pos == NULL_POSITION && where >= 0 && where < sc_height-1) 181 pos = position(++where); 182 if (pos == NULL_POSITION) 183 pos = ch_length(); 184 return (pos); 185 } 186 187 /* 188 * Return the value of a prototype conditional. 189 * A prototype string may include conditionals which consist of a 190 * question mark followed by a single letter. 191 * Here we decode that letter and return the appropriate boolean value. 192 */ 193 static lbool cond(char c, int where) 194 { 195 POSITION len; 196 197 switch (c) 198 { 199 case 'a': /* Anything in the message yet? */ 200 return (mp > message); 201 case 'b': /* Current byte offset known? */ 202 return (curr_byte(where) != NULL_POSITION); 203 case 'c': 204 return (hshift != 0); 205 case 'e': /* At end of file? */ 206 return (eof_displayed(FALSE)); 207 case 'f': /* Filename known? */ 208 case 'g': 209 return (strcmp(get_filename(curr_ifile), "-") != 0); 210 case 'l': /* Line number known? */ 211 case 'd': /* Same as l */ 212 if (!linenums) 213 return FALSE; 214 return (currline(where) != 0); 215 case 'L': /* Final line number known? */ 216 case 'D': /* Final page number known? */ 217 return (linenums && ch_length() != NULL_POSITION); 218 case 'm': /* More than one file? */ 219 #if TAGS 220 return (ntags() ? (ntags() > 1) : (nifile() > 1)); 221 #else 222 return (nifile() > 1); 223 #endif 224 case 'n': /* First prompt in a new file? */ 225 #if TAGS 226 return (ntags() ? TRUE : new_file ? TRUE : FALSE); 227 #else 228 return (new_file ? TRUE : FALSE); 229 #endif 230 case 'p': /* Percent into file (bytes) known? */ 231 return (curr_byte(where) != NULL_POSITION && ch_length() > 0); 232 case 'P': /* Percent into file (lines) known? */ 233 return (currline(where) != 0 && 234 (len = ch_length()) > 0 && 235 find_linenum(len) != 0); 236 case 's': /* Size of file known? */ 237 case 'B': 238 return (ch_length() != NULL_POSITION); 239 case 'x': /* Is there a "next" file? */ 240 #if TAGS 241 if (ntags()) 242 return (FALSE); 243 #endif 244 return (next_ifile(curr_ifile) != NULL_IFILE); 245 } 246 return (FALSE); 247 } 248 249 /* 250 * Decode a "percent" prototype character. 251 * A prototype string may include various "percent" escapes; 252 * that is, a percent sign followed by a single letter. 253 * Here we decode that letter and take the appropriate action, 254 * usually by appending something to the message being built. 255 */ 256 static void protochar(char c, int where) 257 { 258 POSITION pos; 259 POSITION len; 260 LINENUM linenum; 261 LINENUM last_linenum; 262 IFILE h; 263 char *s; 264 265 #undef PAGE_NUM 266 #define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - header_lines - 1)) + 1) 267 268 switch (c) 269 { 270 case 'b': /* Current byte offset */ 271 pos = curr_byte(where); 272 if (pos != NULL_POSITION) 273 ap_pos(pos); 274 else 275 ap_quest(); 276 break; 277 case 'c': 278 ap_int(hshift); 279 break; 280 case 'd': /* Current page number */ 281 linenum = currline(where); 282 if (linenum > 0 && sc_height > header_lines + 1) 283 ap_linenum(PAGE_NUM(linenum)); 284 else 285 ap_quest(); 286 break; 287 case 'D': /* Final page number */ 288 /* Find the page number of the last byte in the file (len-1). */ 289 len = ch_length(); 290 if (len == NULL_POSITION) 291 ap_quest(); 292 else if (len == 0) 293 /* An empty file has no pages. */ 294 ap_linenum(0); 295 else 296 { 297 linenum = find_linenum(len - 1); 298 if (linenum <= 0) 299 ap_quest(); 300 else 301 ap_linenum(PAGE_NUM(linenum)); 302 } 303 break; 304 #if EDITOR 305 case 'E': /* Editor name */ 306 ap_str(editor); 307 break; 308 #endif 309 case 'f': /* File name */ 310 ap_estr(get_filename(curr_ifile), TRUE); 311 break; 312 case 'F': /* Last component of file name */ 313 ap_estr(last_component(get_filename(curr_ifile)), TRUE); 314 break; 315 case 'g': /* Shell-escaped file name */ 316 s = shell_quote(get_filename(curr_ifile)); 317 ap_str(s); 318 free(s); 319 break; 320 case 'i': /* Index into list of files */ 321 #if TAGS 322 if (ntags()) 323 ap_int(curr_tag()); 324 else 325 #endif 326 ap_int(get_index(curr_ifile)); 327 break; 328 case 'l': /* Current line number */ 329 linenum = currline(where); 330 if (linenum != 0) 331 ap_linenum(vlinenum(linenum)); 332 else 333 ap_quest(); 334 break; 335 case 'L': /* Final line number */ 336 len = ch_length(); 337 if (len == NULL_POSITION || len == ch_zero() || 338 (linenum = find_linenum(len)) <= 0) 339 ap_quest(); 340 else 341 ap_linenum(vlinenum(linenum-1)); 342 break; 343 case 'm': { /* Number of files */ 344 #if TAGS 345 int n = ntags(); 346 if (n) 347 ap_int(n); 348 else 349 #endif 350 ap_int(nifile()); 351 break; } 352 case 'o': /* path (URI without protocol) of selected OSC8 link */ 353 #if OSC8_LINK 354 if (osc8_path != NULL) 355 ap_str(osc8_path); 356 else 357 #endif 358 ap_quest(); 359 break; 360 case 'p': /* Percent into file (bytes) */ 361 pos = curr_byte(where); 362 len = ch_length(); 363 if (pos != NULL_POSITION && len > 0) 364 ap_int(percentage(pos,len)); 365 else 366 ap_quest(); 367 break; 368 case 'P': /* Percent into file (lines) */ 369 linenum = currline(where); 370 if (linenum == 0 || 371 (len = ch_length()) == NULL_POSITION || len == ch_zero() || 372 (last_linenum = find_linenum(len)) <= 0) 373 ap_quest(); 374 else 375 ap_int(percentage(linenum, last_linenum)); 376 break; 377 case 's': /* Size of file */ 378 case 'B': 379 len = ch_length(); 380 if (len != NULL_POSITION) 381 ap_pos(len); 382 else 383 ap_quest(); 384 break; 385 case 't': /* Truncate trailing spaces in the message */ 386 while (mp > message && mp[-1] == ' ') 387 mp--; 388 *mp = '\0'; 389 break; 390 case 'T': /* Type of list */ 391 #if TAGS 392 if (ntags()) 393 ap_str("tag"); 394 else 395 #endif 396 ap_str("file"); 397 break; 398 case 'x': /* Name of next file */ 399 h = next_ifile(curr_ifile); 400 if (h != NULL_IFILE) 401 ap_str(get_filename(h)); 402 else 403 ap_quest(); 404 break; 405 } 406 } 407 408 /* 409 * Skip a false conditional. 410 * When a false condition is found (either a false IF or the ELSE part 411 * of a true IF), this routine scans the prototype string to decide 412 * where to resume parsing the string. 413 * We must keep track of nested IFs and skip them properly. 414 */ 415 static constant char * skipcond(constant char *p) 416 { 417 int iflevel; 418 419 /* 420 * We came in here after processing a ? or :, 421 * so we start nested one level deep. 422 */ 423 iflevel = 1; 424 425 for (;;) switch (*++p) 426 { 427 case '?': 428 /* 429 * Start of a nested IF. 430 */ 431 iflevel++; 432 break; 433 case ':': 434 /* 435 * Else. 436 * If this matches the IF we came in here with, 437 * then we're done. 438 */ 439 if (iflevel == 1) 440 return (p); 441 break; 442 case '.': 443 /* 444 * Endif. 445 * If this matches the IF we came in here with, 446 * then we're done. 447 */ 448 if (--iflevel == 0) 449 return (p); 450 break; 451 case '\\': 452 /* 453 * Backslash escapes the next character. 454 */ 455 if (p[1] != '\0') 456 ++p; 457 break; 458 case '\0': 459 /* 460 * Whoops. Hit end of string. 461 * This is a malformed conditional, but just treat it 462 * as if all active conditionals ends here. 463 */ 464 return (p-1); 465 } 466 /*NOTREACHED*/ 467 } 468 469 /* 470 * Decode a char that represents a position on the screen. 471 */ 472 static constant char * wherechar(char constant *p, int *wp) 473 { 474 switch (*p) 475 { 476 case 'b': case 'd': case 'l': case 'p': case 'P': 477 switch (*++p) 478 { 479 case 't': *wp = TOP; break; 480 case 'm': *wp = MIDDLE; break; 481 case 'b': *wp = BOTTOM; break; 482 case 'B': *wp = BOTTOM_PLUS_ONE; break; 483 case 'j': *wp = sindex_from_sline(jump_sline); break; 484 default: *wp = TOP; p--; break; 485 } 486 } 487 return (p); 488 } 489 490 /* 491 * Construct a message based on a prototype string. 492 */ 493 public constant char * pr_expand(constant char *proto) 494 { 495 constant char *p; 496 char c; 497 int where; 498 499 mp = message; 500 501 if (*proto == '\0') 502 return (""); 503 504 for (p = proto; *p != '\0'; p++) 505 { 506 switch (*p) 507 { 508 default: /* Just put the character in the message */ 509 ap_char(*p); 510 break; 511 case '\\': /* Backslash escapes the next character */ 512 if (p[1] != '\0') 513 ap_char(*++p); 514 break; 515 case '?': /* Conditional (IF) */ 516 if ((c = *++p) == '\0') 517 --p; 518 else 519 { 520 where = 0; 521 p = wherechar(p, &where); 522 if (!cond(c, where)) 523 p = skipcond(p); 524 } 525 break; 526 case ':': /* ELSE */ 527 p = skipcond(p); 528 break; 529 case '.': /* ENDIF */ 530 break; 531 case '%': /* Percent escape */ 532 if ((c = *++p) == '\0') 533 --p; 534 else 535 { 536 where = 0; 537 p = wherechar(p, &where); 538 protochar(c, where); 539 } 540 break; 541 } 542 } 543 544 if (mp == message) 545 return (""); 546 return (message); 547 } 548 549 /* 550 * Return a message suitable for printing by the "=" command. 551 */ 552 public constant char * eq_message(void) 553 { 554 return (pr_expand(eqproto)); 555 } 556 557 /* 558 * Return a prompt. 559 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc. 560 * If we can't come up with an appropriate prompt, return NULL 561 * and the caller will prompt with a colon. 562 */ 563 public constant char * pr_string(void) 564 { 565 constant char *prompt; 566 int type; 567 568 type = (!less_is_more) ? pr_type : pr_type ? 0 : 1; 569 prompt = pr_expand((ch_getflags() & CH_HELPFILE) ? 570 hproto : prproto[type]); 571 new_file = FALSE; 572 return (prompt); 573 } 574 575 /* 576 * Return a message suitable for printing while waiting in the F command. 577 */ 578 public constant char * wait_message(void) 579 { 580 return (pr_expand(wproto)); 581 } 582