1 /* 2 * Copyright (C) 1984-2022 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 int new_file; 25 extern int sc_width; 26 extern int so_s_width, so_e_width; 27 extern int linenums; 28 extern int hshift; 29 extern int sc_height; 30 extern int jump_sline; 31 extern int less_is_more; 32 extern int header_lines; 33 extern IFILE curr_ifile; 34 #if EDITOR 35 extern char *editor; 36 extern char *editproto; 37 #endif 38 39 /* 40 * Prototypes for the three flavors of prompts. 41 * These strings are expanded by pr_expand(). 42 */ 43 static constant char s_proto[] = 44 "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x..%t"; 45 static constant char m_proto[] = 46 "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t"; 47 static constant char M_proto[] = 48 "?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"; 49 static constant char e_proto[] = 50 "?f%f .?m(%T %i of %m) .?ltlines %lt-%lb?L/%L. .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t"; 51 static constant char h_proto[] = 52 "HELP -- ?eEND -- Press g to see it again:Press RETURN for more., or q when done"; 53 static constant char w_proto[] = 54 "Waiting for data"; 55 static constant char more_proto[] = 56 "--More--(?eEND ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t)"; 57 58 public char *prproto[3]; 59 public char constant *eqproto = e_proto; 60 public char constant *hproto = h_proto; 61 public char constant *wproto = w_proto; 62 63 static char message[PROMPT_SIZE]; 64 static char *mp; 65 66 /* 67 * Initialize the prompt prototype strings. 68 */ 69 public void 70 init_prompt(VOID_PARAM) 71 { 72 prproto[0] = save(s_proto); 73 prproto[1] = save(less_is_more ? more_proto : m_proto); 74 prproto[2] = save(M_proto); 75 eqproto = save(e_proto); 76 hproto = save(h_proto); 77 wproto = save(w_proto); 78 } 79 80 /* 81 * Append a string to the end of the message. 82 */ 83 static void 84 ap_str(s) 85 char *s; 86 { 87 int len; 88 89 len = (int) strlen(s); 90 if (mp + len >= message + PROMPT_SIZE) 91 len = (int) (message + PROMPT_SIZE - mp - 1); 92 strncpy(mp, s, len); 93 mp += len; 94 *mp = '\0'; 95 } 96 97 /* 98 * Append a character to the end of the message. 99 */ 100 static void 101 ap_char(c) 102 char c; 103 { 104 char buf[2]; 105 106 buf[0] = c; 107 buf[1] = '\0'; 108 ap_str(buf); 109 } 110 111 /* 112 * Append a POSITION (as a decimal integer) to the end of the message. 113 */ 114 static void 115 ap_pos(pos) 116 POSITION pos; 117 { 118 char buf[INT_STRLEN_BOUND(pos) + 2]; 119 120 postoa(pos, buf); 121 ap_str(buf); 122 } 123 124 /* 125 * Append a line number to the end of the message. 126 */ 127 static void 128 ap_linenum(linenum) 129 LINENUM linenum; 130 { 131 char buf[INT_STRLEN_BOUND(linenum) + 2]; 132 133 linenumtoa(linenum, buf); 134 ap_str(buf); 135 } 136 137 /* 138 * Append an integer to the end of the message. 139 */ 140 static void 141 ap_int(num) 142 int num; 143 { 144 char buf[INT_STRLEN_BOUND(num) + 2]; 145 146 inttoa(num, buf); 147 ap_str(buf); 148 } 149 150 /* 151 * Append a question mark to the end of the message. 152 */ 153 static void 154 ap_quest(VOID_PARAM) 155 { 156 ap_str("?"); 157 } 158 159 /* 160 * Return the "current" byte offset in the file. 161 */ 162 static POSITION 163 curr_byte(where) 164 int where; 165 { 166 POSITION pos; 167 168 pos = position(where); 169 while (pos == NULL_POSITION && where >= 0 && where < sc_height-1) 170 pos = position(++where); 171 if (pos == NULL_POSITION) 172 pos = ch_length(); 173 return (pos); 174 } 175 176 /* 177 * Return the value of a prototype conditional. 178 * A prototype string may include conditionals which consist of a 179 * question mark followed by a single letter. 180 * Here we decode that letter and return the appropriate boolean value. 181 */ 182 static int 183 cond(c, where) 184 char c; 185 int where; 186 { 187 POSITION len; 188 189 switch (c) 190 { 191 case 'a': /* Anything in the message yet? */ 192 return (mp > message); 193 case 'b': /* Current byte offset known? */ 194 return (curr_byte(where) != NULL_POSITION); 195 case 'c': 196 return (hshift != 0); 197 case 'e': /* At end of file? */ 198 return (eof_displayed()); 199 case 'f': /* Filename known? */ 200 case 'g': 201 return (strcmp(get_filename(curr_ifile), "-") != 0); 202 case 'l': /* Line number known? */ 203 case 'd': /* Same as l */ 204 if (!linenums) 205 return 0; 206 return (currline(where) != 0); 207 case 'L': /* Final line number known? */ 208 case 'D': /* Final page number known? */ 209 return (linenums && ch_length() != NULL_POSITION); 210 case 'm': /* More than one file? */ 211 #if TAGS 212 return (ntags() ? (ntags() > 1) : (nifile() > 1)); 213 #else 214 return (nifile() > 1); 215 #endif 216 case 'n': /* First prompt in a new file? */ 217 #if TAGS 218 return (ntags() ? 1 : new_file); 219 #else 220 return (new_file); 221 #endif 222 case 'p': /* Percent into file (bytes) known? */ 223 return (curr_byte(where) != NULL_POSITION && 224 ch_length() > 0); 225 case 'P': /* Percent into file (lines) known? */ 226 return (currline(where) != 0 && 227 (len = ch_length()) > 0 && 228 find_linenum(len) != 0); 229 case 's': /* Size of file known? */ 230 case 'B': 231 return (ch_length() != NULL_POSITION); 232 case 'x': /* Is there a "next" file? */ 233 #if TAGS 234 if (ntags()) 235 return (0); 236 #endif 237 return (next_ifile(curr_ifile) != NULL_IFILE); 238 } 239 return (0); 240 } 241 242 /* 243 * Decode a "percent" prototype character. 244 * A prototype string may include various "percent" escapes; 245 * that is, a percent sign followed by a single letter. 246 * Here we decode that letter and take the appropriate action, 247 * usually by appending something to the message being built. 248 */ 249 static void 250 protochar(c, where, iseditproto) 251 int c; 252 int where; 253 int iseditproto; 254 { 255 POSITION pos; 256 POSITION len; 257 int n; 258 LINENUM linenum; 259 LINENUM last_linenum; 260 IFILE h; 261 char *s; 262 263 #undef PAGE_NUM 264 #define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - header_lines - 1)) + 1) 265 266 switch (c) 267 { 268 case 'b': /* Current byte offset */ 269 pos = curr_byte(where); 270 if (pos != NULL_POSITION) 271 ap_pos(pos); 272 else 273 ap_quest(); 274 break; 275 case 'c': 276 ap_int(hshift); 277 break; 278 case 'd': /* Current page number */ 279 linenum = currline(where); 280 if (linenum > 0 && sc_height > header_lines + 1) 281 ap_linenum(PAGE_NUM(linenum)); 282 else 283 ap_quest(); 284 break; 285 case 'D': /* Final page number */ 286 /* Find the page number of the last byte in the file (len-1). */ 287 len = ch_length(); 288 if (len == NULL_POSITION) 289 ap_quest(); 290 else if (len == 0) 291 /* An empty file has no pages. */ 292 ap_linenum(0); 293 else 294 { 295 linenum = find_linenum(len - 1); 296 if (linenum <= 0) 297 ap_quest(); 298 else 299 ap_linenum(PAGE_NUM(linenum)); 300 } 301 break; 302 #if EDITOR 303 case 'E': /* Editor name */ 304 ap_str(editor); 305 break; 306 #endif 307 case 'f': /* File name */ 308 ap_str(get_filename(curr_ifile)); 309 break; 310 case 'F': /* Last component of file name */ 311 ap_str(last_component(get_filename(curr_ifile))); 312 break; 313 case 'g': /* Shell-escaped file name */ 314 s = shell_quote(get_filename(curr_ifile)); 315 ap_str(s); 316 free(s); 317 break; 318 case 'i': /* Index into list of files */ 319 #if TAGS 320 if (ntags()) 321 ap_int(curr_tag()); 322 else 323 #endif 324 ap_int(get_index(curr_ifile)); 325 break; 326 case 'l': /* Current line number */ 327 linenum = currline(where); 328 if (linenum != 0) 329 ap_linenum(vlinenum(linenum)); 330 else 331 ap_quest(); 332 break; 333 case 'L': /* Final line number */ 334 len = ch_length(); 335 if (len == NULL_POSITION || len == ch_zero() || 336 (linenum = find_linenum(len)) <= 0) 337 ap_quest(); 338 else 339 ap_linenum(vlinenum(linenum-1)); 340 break; 341 case 'm': /* Number of files */ 342 #if TAGS 343 n = ntags(); 344 if (n) 345 ap_int(n); 346 else 347 #endif 348 ap_int(nifile()); 349 break; 350 case 'p': /* Percent into file (bytes) */ 351 pos = curr_byte(where); 352 len = ch_length(); 353 if (pos != NULL_POSITION && len > 0) 354 ap_int(percentage(pos,len)); 355 else 356 ap_quest(); 357 break; 358 case 'P': /* Percent into file (lines) */ 359 linenum = currline(where); 360 if (linenum == 0 || 361 (len = ch_length()) == NULL_POSITION || len == ch_zero() || 362 (last_linenum = find_linenum(len)) <= 0) 363 ap_quest(); 364 else 365 ap_int(percentage(linenum, last_linenum)); 366 break; 367 case 's': /* Size of file */ 368 case 'B': 369 len = ch_length(); 370 if (len != NULL_POSITION) 371 ap_pos(len); 372 else 373 ap_quest(); 374 break; 375 case 't': /* Truncate trailing spaces in the message */ 376 while (mp > message && mp[-1] == ' ') 377 mp--; 378 *mp = '\0'; 379 break; 380 case 'T': /* Type of list */ 381 #if TAGS 382 if (ntags()) 383 ap_str("tag"); 384 else 385 #endif 386 ap_str("file"); 387 break; 388 case 'x': /* Name of next file */ 389 h = next_ifile(curr_ifile); 390 if (h != NULL_IFILE) 391 ap_str(get_filename(h)); 392 else 393 ap_quest(); 394 break; 395 } 396 } 397 398 /* 399 * Skip a false conditional. 400 * When a false condition is found (either a false IF or the ELSE part 401 * of a true IF), this routine scans the prototype string to decide 402 * where to resume parsing the string. 403 * We must keep track of nested IFs and skip them properly. 404 */ 405 static constant char * 406 skipcond(p) 407 constant char *p; 408 { 409 int iflevel; 410 411 /* 412 * We came in here after processing a ? or :, 413 * so we start nested one level deep. 414 */ 415 iflevel = 1; 416 417 for (;;) switch (*++p) 418 { 419 case '?': 420 /* 421 * Start of a nested IF. 422 */ 423 iflevel++; 424 break; 425 case ':': 426 /* 427 * Else. 428 * If this matches the IF we came in here with, 429 * then we're done. 430 */ 431 if (iflevel == 1) 432 return (p); 433 break; 434 case '.': 435 /* 436 * Endif. 437 * If this matches the IF we came in here with, 438 * then we're done. 439 */ 440 if (--iflevel == 0) 441 return (p); 442 break; 443 case '\\': 444 /* 445 * Backslash escapes the next character. 446 */ 447 ++p; 448 break; 449 case '\0': 450 /* 451 * Whoops. Hit end of string. 452 * This is a malformed conditional, but just treat it 453 * as if all active conditionals ends here. 454 */ 455 return (p-1); 456 } 457 /*NOTREACHED*/ 458 } 459 460 /* 461 * Decode a char that represents a position on the screen. 462 */ 463 static constant char * 464 wherechar(p, wp) 465 char constant *p; 466 int *wp; 467 { 468 switch (*p) 469 { 470 case 'b': case 'd': case 'l': case 'p': case 'P': 471 switch (*++p) 472 { 473 case 't': *wp = TOP; break; 474 case 'm': *wp = MIDDLE; break; 475 case 'b': *wp = BOTTOM; break; 476 case 'B': *wp = BOTTOM_PLUS_ONE; break; 477 case 'j': *wp = sindex_from_sline(jump_sline); break; 478 default: *wp = TOP; p--; break; 479 } 480 } 481 return (p); 482 } 483 484 /* 485 * Construct a message based on a prototype string. 486 */ 487 public char * 488 pr_expand(proto) 489 constant char *proto; 490 { 491 constant char *p; 492 int c; 493 int where; 494 495 mp = message; 496 497 if (*proto == '\0') 498 return (""); 499 500 for (p = proto; *p != '\0'; p++) 501 { 502 switch (*p) 503 { 504 default: /* Just put the character in the message */ 505 ap_char(*p); 506 break; 507 case '\\': /* Backslash escapes the next character */ 508 p++; 509 ap_char(*p); 510 break; 511 case '?': /* Conditional (IF) */ 512 if ((c = *++p) == '\0') 513 --p; 514 else 515 { 516 where = 0; 517 p = wherechar(p, &where); 518 if (!cond(c, where)) 519 p = skipcond(p); 520 } 521 break; 522 case ':': /* ELSE */ 523 p = skipcond(p); 524 break; 525 case '.': /* ENDIF */ 526 break; 527 case '%': /* Percent escape */ 528 if ((c = *++p) == '\0') 529 --p; 530 else 531 { 532 where = 0; 533 p = wherechar(p, &where); 534 protochar(c, where, 535 #if EDITOR 536 (proto == editproto)); 537 #else 538 0); 539 #endif 540 541 } 542 break; 543 } 544 } 545 546 if (mp == message) 547 return (""); 548 return (message); 549 } 550 551 /* 552 * Return a message suitable for printing by the "=" command. 553 */ 554 public char * 555 eq_message(VOID_PARAM) 556 { 557 return (pr_expand(eqproto)); 558 } 559 560 /* 561 * Return a prompt. 562 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc. 563 * If we can't come up with an appropriate prompt, return NULL 564 * and the caller will prompt with a colon. 565 */ 566 public char * 567 pr_string(VOID_PARAM) 568 { 569 char *prompt; 570 int type; 571 572 type = (!less_is_more) ? pr_type : pr_type ? 0 : 1; 573 prompt = pr_expand((ch_getflags() & CH_HELPFILE) ? 574 hproto : prproto[type]); 575 new_file = 0; 576 return (prompt); 577 } 578 579 /* 580 * Return a message suitable for printing while waiting in the F command. 581 */ 582 public char * 583 wait_message(VOID_PARAM) 584 { 585 return (pr_expand(wproto)); 586 } 587