1 /* $NetBSD: prompt.c,v 1.5 2023/10/06 05:49:49 simonb Exp $ */ 2 3 /* 4 * Copyright (C) 1984-2023 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, see the README file. 10 */ 11 12 13 /* 14 * Prompting and other messages. 15 * There are three flavors of prompts, SHORT, MEDIUM and LONG, 16 * selected by the -m/-M options. 17 * There is also the "equals message", printed by the = command. 18 * A prompt is a message composed of various pieces, such as the 19 * name of the file being viewed, the percentage into the file, etc. 20 */ 21 22 #include "less.h" 23 #include "position.h" 24 25 extern int pr_type; 26 extern int new_file; 27 extern int sc_width; 28 extern int so_s_width, so_e_width; 29 extern int linenums; 30 extern int hshift; 31 extern int sc_height; 32 extern int jump_sline; 33 extern int less_is_more; 34 extern int header_lines; 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 constant *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 */ 84 static void ap_str(char *s) 85 { 86 int len; 87 88 len = (int) strlen(s); 89 if (mp + len >= message + PROMPT_SIZE) 90 len = (int) (message + PROMPT_SIZE - mp - 1); 91 strncpy(mp, s, len); 92 mp += len; 93 *mp = '\0'; 94 } 95 96 /* 97 * Append a character to the end of the message. 98 */ 99 static void ap_char(char c) 100 { 101 char buf[2]; 102 103 buf[0] = c; 104 buf[1] = '\0'; 105 ap_str(buf); 106 } 107 108 /* 109 * Append a POSITION (as a decimal integer) to the end of the message. 110 */ 111 static void ap_pos(POSITION pos) 112 { 113 char buf[INT_STRLEN_BOUND(pos) + 2]; 114 115 postoa(pos, buf, 10); 116 ap_str(buf); 117 } 118 119 /* 120 * Append a line number to the end of the message. 121 */ 122 static void ap_linenum(LINENUM linenum) 123 { 124 char buf[INT_STRLEN_BOUND(linenum) + 2]; 125 126 linenumtoa(linenum, buf, 10); 127 ap_str(buf); 128 } 129 130 /* 131 * Append an integer to the end of the message. 132 */ 133 static void ap_int(int num) 134 { 135 char buf[INT_STRLEN_BOUND(num) + 2]; 136 137 inttoa(num, buf, 10); 138 ap_str(buf); 139 } 140 141 /* 142 * Append a question mark to the end of the message. 143 */ 144 static void ap_quest(void) 145 { 146 ap_str("?"); 147 } 148 149 /* 150 * Return the "current" byte offset in the file. 151 */ 152 static POSITION curr_byte(int where) 153 { 154 POSITION pos; 155 156 pos = position(where); 157 while (pos == NULL_POSITION && where >= 0 && where < sc_height-1) 158 pos = position(++where); 159 if (pos == NULL_POSITION) 160 pos = ch_length(); 161 return (pos); 162 } 163 164 /* 165 * Return the value of a prototype conditional. 166 * A prototype string may include conditionals which consist of a 167 * question mark followed by a single letter. 168 * Here we decode that letter and return the appropriate boolean value. 169 */ 170 static int cond(char c, int where) 171 { 172 POSITION len; 173 174 switch (c) 175 { 176 case 'a': /* Anything in the message yet? */ 177 return (mp > message); 178 case 'b': /* Current byte offset known? */ 179 return (curr_byte(where) != NULL_POSITION); 180 case 'c': 181 return (hshift != 0); 182 case 'e': /* At end of file? */ 183 return (eof_displayed()); 184 case 'f': /* Filename known? */ 185 case 'g': 186 return (strcmp(get_filename(curr_ifile), "-") != 0); 187 case 'l': /* Line number known? */ 188 case 'd': /* Same as l */ 189 if (!linenums) 190 return 0; 191 return (currline(where) != 0); 192 case 'L': /* Final line number known? */ 193 case 'D': /* Final page number known? */ 194 return (linenums && ch_length() != NULL_POSITION); 195 case 'm': /* More than one file? */ 196 #if TAGS 197 return (ntags() ? (ntags() > 1) : (nifile() > 1)); 198 #else 199 return (nifile() > 1); 200 #endif 201 case 'n': /* First prompt in a new file? */ 202 #if TAGS 203 return (ntags() ? 1 : new_file); 204 #else 205 return (new_file); 206 #endif 207 case 'p': /* Percent into file (bytes) known? */ 208 return (curr_byte(where) != NULL_POSITION && 209 ch_length() > 0); 210 case 'P': /* Percent into file (lines) known? */ 211 return (currline(where) != 0 && 212 (len = ch_length()) > 0 && 213 find_linenum(len) != 0); 214 case 's': /* Size of file known? */ 215 case 'B': 216 return (ch_length() != NULL_POSITION); 217 case 'x': /* Is there a "next" file? */ 218 #if TAGS 219 if (ntags()) 220 return (0); 221 #endif 222 return (next_ifile(curr_ifile) != NULL_IFILE); 223 } 224 return (0); 225 } 226 227 /* 228 * Decode a "percent" prototype character. 229 * A prototype string may include various "percent" escapes; 230 * that is, a percent sign followed by a single letter. 231 * Here we decode that letter and take the appropriate action, 232 * usually by appending something to the message being built. 233 */ 234 static void protochar(int c, int where, int iseditproto) 235 { 236 POSITION pos; 237 POSITION len; 238 int n; 239 LINENUM linenum; 240 LINENUM last_linenum; 241 IFILE h; 242 char *s; 243 244 #undef PAGE_NUM 245 #define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - header_lines - 1)) + 1) 246 247 switch (c) 248 { 249 case 'b': /* Current byte offset */ 250 pos = curr_byte(where); 251 if (pos != NULL_POSITION) 252 ap_pos(pos); 253 else 254 ap_quest(); 255 break; 256 case 'c': 257 ap_int(hshift); 258 break; 259 case 'd': /* Current page number */ 260 linenum = currline(where); 261 if (linenum > 0 && sc_height > header_lines + 1) 262 ap_linenum(PAGE_NUM(linenum)); 263 else 264 ap_quest(); 265 break; 266 case 'D': /* Final page number */ 267 /* Find the page number of the last byte in the file (len-1). */ 268 len = ch_length(); 269 if (len == NULL_POSITION) 270 ap_quest(); 271 else if (len == 0) 272 /* An empty file has no pages. */ 273 ap_linenum(0); 274 else 275 { 276 linenum = find_linenum(len - 1); 277 if (linenum <= 0) 278 ap_quest(); 279 else 280 ap_linenum(PAGE_NUM(linenum)); 281 } 282 break; 283 #if EDITOR 284 case 'E': /* Editor name */ 285 ap_str(editor); 286 break; 287 #endif 288 case 'f': /* File name */ 289 ap_str(get_filename(curr_ifile)); 290 break; 291 case 'F': /* Last component of file name */ 292 ap_str(last_component(get_filename(curr_ifile))); 293 break; 294 case 'g': /* Shell-escaped file name */ 295 s = shell_quote(get_filename(curr_ifile)); 296 ap_str(s); 297 free(s); 298 break; 299 case 'i': /* Index into list of files */ 300 #if TAGS 301 if (ntags()) 302 ap_int(curr_tag()); 303 else 304 #endif 305 ap_int(get_index(curr_ifile)); 306 break; 307 case 'l': /* Current line number */ 308 linenum = currline(where); 309 if (linenum != 0) 310 ap_linenum(vlinenum(linenum)); 311 else 312 ap_quest(); 313 break; 314 case 'L': /* Final line number */ 315 len = ch_length(); 316 if (len == NULL_POSITION || len == ch_zero() || 317 (linenum = find_linenum(len)) <= 0) 318 ap_quest(); 319 else 320 ap_linenum(vlinenum(linenum-1)); 321 break; 322 case 'm': /* Number of files */ 323 #if TAGS 324 n = ntags(); 325 if (n) 326 ap_int(n); 327 else 328 #endif 329 ap_int(nifile()); 330 break; 331 case 'p': /* Percent into file (bytes) */ 332 pos = curr_byte(where); 333 len = ch_length(); 334 if (pos != NULL_POSITION && len > 0) 335 ap_int(percentage(pos,len)); 336 else 337 ap_quest(); 338 break; 339 case 'P': /* Percent into file (lines) */ 340 linenum = currline(where); 341 if (linenum == 0 || 342 (len = ch_length()) == NULL_POSITION || len == ch_zero() || 343 (last_linenum = find_linenum(len)) <= 0) 344 ap_quest(); 345 else 346 ap_int(percentage(linenum, last_linenum)); 347 break; 348 case 's': /* Size of file */ 349 case 'B': 350 len = ch_length(); 351 if (len != NULL_POSITION) 352 ap_pos(len); 353 else 354 ap_quest(); 355 break; 356 case 't': /* Truncate trailing spaces in the message */ 357 while (mp > message && mp[-1] == ' ') 358 mp--; 359 *mp = '\0'; 360 break; 361 case 'T': /* Type of list */ 362 #if TAGS 363 if (ntags()) 364 ap_str("tag"); 365 else 366 #endif 367 ap_str("file"); 368 break; 369 case 'x': /* Name of next file */ 370 h = next_ifile(curr_ifile); 371 if (h != NULL_IFILE) 372 ap_str(get_filename(h)); 373 else 374 ap_quest(); 375 break; 376 } 377 } 378 379 /* 380 * Skip a false conditional. 381 * When a false condition is found (either a false IF or the ELSE part 382 * of a true IF), this routine scans the prototype string to decide 383 * where to resume parsing the string. 384 * We must keep track of nested IFs and skip them properly. 385 */ 386 static constant char * skipcond(constant char *p) 387 { 388 int iflevel; 389 390 /* 391 * We came in here after processing a ? or :, 392 * so we start nested one level deep. 393 */ 394 iflevel = 1; 395 396 for (;;) switch (*++p) 397 { 398 case '?': 399 /* 400 * Start of a nested IF. 401 */ 402 iflevel++; 403 break; 404 case ':': 405 /* 406 * Else. 407 * If this matches the IF we came in here with, 408 * then we're done. 409 */ 410 if (iflevel == 1) 411 return (p); 412 break; 413 case '.': 414 /* 415 * Endif. 416 * If this matches the IF we came in here with, 417 * then we're done. 418 */ 419 if (--iflevel == 0) 420 return (p); 421 break; 422 case '\\': 423 /* 424 * Backslash escapes the next character. 425 */ 426 if (p[1] != '\0') 427 ++p; 428 break; 429 case '\0': 430 /* 431 * Whoops. Hit end of string. 432 * This is a malformed conditional, but just treat it 433 * as if all active conditionals ends here. 434 */ 435 return (p-1); 436 } 437 /*NOTREACHED*/ 438 } 439 440 /* 441 * Decode a char that represents a position on the screen. 442 */ 443 static constant char * wherechar(char constant *p, int *wp) 444 { 445 switch (*p) 446 { 447 case 'b': case 'd': case 'l': case 'p': case 'P': 448 switch (*++p) 449 { 450 case 't': *wp = TOP; break; 451 case 'm': *wp = MIDDLE; break; 452 case 'b': *wp = BOTTOM; break; 453 case 'B': *wp = BOTTOM_PLUS_ONE; break; 454 case 'j': *wp = sindex_from_sline(jump_sline); break; 455 default: *wp = TOP; p--; break; 456 } 457 } 458 return (p); 459 } 460 461 /* 462 * Construct a message based on a prototype string. 463 */ 464 public char * pr_expand(constant char *proto) 465 { 466 constant char *p; 467 int c; 468 int where; 469 470 mp = message; 471 472 if (*proto == '\0') 473 return (""); 474 475 for (p = proto; *p != '\0'; p++) 476 { 477 switch (*p) 478 { 479 default: /* Just put the character in the message */ 480 ap_char(*p); 481 break; 482 case '\\': /* Backslash escapes the next character */ 483 if (p[1] != '\0') 484 ap_char(*++p); 485 break; 486 case '?': /* Conditional (IF) */ 487 if ((c = *++p) == '\0') 488 --p; 489 else 490 { 491 where = 0; 492 p = wherechar(p, &where); 493 if (!cond(c, where)) 494 p = skipcond(p); 495 } 496 break; 497 case ':': /* ELSE */ 498 p = skipcond(p); 499 break; 500 case '.': /* ENDIF */ 501 break; 502 case '%': /* Percent escape */ 503 if ((c = *++p) == '\0') 504 --p; 505 else 506 { 507 where = 0; 508 p = wherechar(p, &where); 509 protochar(c, where, 510 #if EDITOR 511 (proto == editproto)); 512 #else 513 0); 514 #endif 515 516 } 517 break; 518 } 519 } 520 521 if (mp == message) 522 return (""); 523 return (message); 524 } 525 526 /* 527 * Return a message suitable for printing by the "=" command. 528 */ 529 public char * eq_message(void) 530 { 531 return (pr_expand(eqproto)); 532 } 533 534 /* 535 * Return a prompt. 536 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc. 537 * If we can't come up with an appropriate prompt, return NULL 538 * and the caller will prompt with a colon. 539 */ 540 public char * pr_string(void) 541 { 542 char *prompt; 543 int type; 544 545 type = (!less_is_more) ? pr_type : pr_type ? 0 : 1; 546 prompt = pr_expand((ch_getflags() & CH_HELPFILE) ? 547 hproto : prproto[type]); 548 new_file = 0; 549 return (prompt); 550 } 551 552 /* 553 * Return a message suitable for printing while waiting in the F command. 554 */ 555 public char * wait_message(void) 556 { 557 return (pr_expand(wproto)); 558 } 559
Indexes created Mon Jun 22 00:25:11 UTC 2026