1 /* $FreeBSD$ */ 2 /* 3 * Copyright (C) 1984-2000 Mark Nudelman 4 * 5 * You may distribute under the terms of either the GNU General Public 6 * License or the Less License, as specified in the README file. 7 * 8 * For more information about less, or for information on how to 9 * contact the author, 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 hit_eof; 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 IFILE curr_ifile; 35 #if EDITOR 36 extern char *editor; 37 extern char *editproto; 38 #endif 39 40 /* 41 * Prototypes for the three flavors of prompts. 42 * These strings are expanded by pr_expand(). 43 */ 44 static constant char s_proto[] = 45 "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x..%t"; 46 static constant char m_proto[] = 47 "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t"; 48 static constant char M_proto[] = 49 "?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"; 50 static constant char e_proto[] = 51 "?f%f .?m(%T %i of %m) .?ltlines %lt-%lb?L/%L. .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t"; 52 static constant char h_proto[] = 53 "HELP -- ?eEND -- Press g to see it again:Press RETURN for more., or q when done"; 54 static constant char w_proto[] = 55 "Waiting for data"; 56 57 public char *prproto[3]; 58 public char constant *eqproto = e_proto; 59 public char constant *hproto = h_proto; 60 public char constant *wproto = w_proto; 61 62 static char message[PROMPT_SIZE]; 63 static char *mp; 64 65 /* 66 * Initialize the prompt prototype strings. 67 */ 68 public void 69 init_prompt() 70 { 71 prproto[0] = save(s_proto); 72 prproto[1] = save(m_proto); 73 prproto[2] = save(M_proto); 74 eqproto = save(e_proto); 75 hproto = save(h_proto); 76 wproto = save(w_proto); 77 } 78 79 /* 80 * Append a string to the end of the message. 81 */ 82 static void 83 ap_str(s) 84 char *s; 85 { 86 int len; 87 88 len = strlen(s); 89 if (mp + len >= message + PROMPT_SIZE) 90 len = 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 100 ap_char(c) 101 char c; 102 { 103 char buf[2]; 104 105 buf[0] = c; 106 buf[1] = '\0'; 107 ap_str(buf); 108 } 109 110 /* 111 * Append a POSITION (as a decimal integer) to the end of the message. 112 */ 113 static void 114 ap_pos(pos) 115 POSITION pos; 116 { 117 char buf[INT_STRLEN_BOUND(pos) + 1]; 118 char *p = buf + sizeof(buf) - 1; 119 int neg = (pos < 0); 120 121 if (neg) 122 pos = -pos; 123 *p = '\0'; 124 do 125 *--p = '0' + (pos % 10); 126 while ((pos /= 10) != 0); 127 if (neg) 128 *--p = '-'; 129 ap_str(p); 130 } 131 132 /* 133 * Append an integer to the end of the message. 134 */ 135 static void 136 ap_int(n) 137 int n; 138 { 139 char buf[INT_STRLEN_BOUND(n) + 1]; 140 141 sprintf(buf, "%d", n); 142 ap_str(buf); 143 } 144 145 /* 146 * Append a question mark to the end of the message. 147 */ 148 static void 149 ap_quest() 150 { 151 ap_str("?"); 152 } 153 154 /* 155 * Return the "current" byte offset in the file. 156 */ 157 static POSITION 158 curr_byte(where) 159 int where; 160 { 161 POSITION pos; 162 163 pos = position(where); 164 while (pos == NULL_POSITION && where >= 0 && where < sc_height) 165 pos = position(++where); 166 if (pos == NULL_POSITION) 167 pos = ch_length(); 168 return (pos); 169 } 170 171 /* 172 * Return the value of a prototype conditional. 173 * A prototype string may include conditionals which consist of a 174 * question mark followed by a single letter. 175 * Here we decode that letter and return the appropriate boolean value. 176 */ 177 static int 178 cond(c, where) 179 char c; 180 int where; 181 { 182 POSITION len; 183 184 switch (c) 185 { 186 case 'a': /* Anything in the message yet? */ 187 return (mp > message); 188 case 'b': /* Current byte offset known? */ 189 return (curr_byte(where) != NULL_POSITION); 190 case 'c': 191 return (hshift != 0); 192 case 'e': /* At end of file? */ 193 return (hit_eof); 194 case 'f': /* Filename known? */ 195 return (strcmp(get_filename(curr_ifile), "-") != 0); 196 case 'l': /* Line number known? */ 197 case 'd': /* Same as l */ 198 return (linenums); 199 case 'L': /* Final line number known? */ 200 case 'D': /* Same as L */ 201 return (linenums && ch_length() != NULL_POSITION); 202 case 'm': /* More than one file? */ 203 return (ntags() ? (ntags() > 1) : (nifile() > 1)); 204 case 'n': /* First prompt in a new file? */ 205 return (ntags() ? 1 : new_file); 206 case 'p': /* Percent into file (bytes) known? */ 207 return (curr_byte(where) != NULL_POSITION && 208 ch_length() > 0); 209 case 'P': /* Percent into file (lines) known? */ 210 return (currline(where) != 0 && 211 (len = ch_length()) > 0 && 212 find_linenum(len) != 0); 213 case 's': /* Size of file known? */ 214 case 'B': 215 return (ch_length() != NULL_POSITION); 216 case 'x': /* Is there a "next" file? */ 217 if (ntags()) 218 return (0); 219 return (next_ifile(curr_ifile) != NULL_IFILE); 220 } 221 return (0); 222 } 223 224 /* 225 * Decode a "percent" prototype character. 226 * A prototype string may include various "percent" escapes; 227 * that is, a percent sign followed by a single letter. 228 * Here we decode that letter and take the appropriate action, 229 * usually by appending something to the message being built. 230 */ 231 static void 232 protochar(c, where, iseditproto) 233 int c; 234 int where; 235 int iseditproto; 236 { 237 POSITION pos; 238 POSITION len; 239 int n; 240 IFILE h; 241 char *s; 242 char *escs; 243 244 switch (c) 245 { 246 case 'b': /* Current byte offset */ 247 pos = curr_byte(where); 248 if (pos != NULL_POSITION) 249 ap_pos(pos); 250 else 251 ap_quest(); 252 break; 253 case 'c': 254 ap_int(hshift); 255 break; 256 case 'd': /* Current page number */ 257 n = currline(where); 258 if (n > 0 && sc_height > 1) 259 ap_int(((n - 1) / (sc_height - 1)) + 1); 260 else 261 ap_quest(); 262 break; 263 case 'D': /* Last page number */ 264 len = ch_length(); 265 if (len == NULL_POSITION || len == ch_zero() || 266 (n = find_linenum(len)) <= 0) 267 ap_quest(); 268 else 269 ap_int(((n - 1) / (sc_height - 1)) + 1); 270 break; 271 #if EDITOR 272 case 'E': /* Editor name */ 273 ap_str(editor); 274 break; 275 #endif 276 case 'f': /* File name */ 277 s = unquote_file(get_filename(curr_ifile)); 278 /* 279 * If we are expanding editproto then we escape metachars. 280 * This allows us to run the editor on files with funny names. 281 */ 282 if (iseditproto && (escs = esc_metachars(s)) != NULL) 283 { 284 free(s); 285 s = escs; 286 } 287 ap_str(s); 288 free(s); 289 break; 290 case 'i': /* Index into list of files */ 291 if (ntags()) 292 ap_int(curr_tag()); 293 else 294 ap_int(get_index(curr_ifile)); 295 break; 296 case 'l': /* Current line number */ 297 n = currline(where); 298 if (n != 0) 299 ap_int(n); 300 else 301 ap_quest(); 302 break; 303 case 'L': /* Final line number */ 304 len = ch_length(); 305 if (len == NULL_POSITION || len == ch_zero() || 306 (n = find_linenum(len)) <= 0) 307 ap_quest(); 308 else 309 ap_int(n-1); 310 break; 311 case 'm': /* Number of files */ 312 n = ntags(); 313 if (n) 314 ap_int(n); 315 else 316 ap_int(nifile()); 317 break; 318 case 'p': /* Percent into file (bytes) */ 319 pos = curr_byte(where); 320 len = ch_length(); 321 if (pos != NULL_POSITION && len > 0) 322 ap_int(percentage(pos,len)); 323 else 324 ap_quest(); 325 break; 326 case 'P': /* Percent into file (lines) */ 327 pos = (POSITION) currline(where); 328 if (pos == 0 || 329 (len = ch_length()) == NULL_POSITION || len == ch_zero() || 330 (n = find_linenum(len)) <= 0) 331 ap_quest(); 332 else 333 ap_int(percentage(pos, (POSITION)n)); 334 break; 335 case 's': /* Size of file */ 336 case 'B': 337 len = ch_length(); 338 if (len != NULL_POSITION) 339 ap_pos(len); 340 else 341 ap_quest(); 342 break; 343 case 't': /* Truncate trailing spaces in the message */ 344 while (mp > message && mp[-1] == ' ') 345 mp--; 346 break; 347 case 'T': /* Type of list */ 348 if (ntags()) 349 ap_str("tag"); 350 else 351 ap_str("file"); 352 break; 353 case 'x': /* Name of next file */ 354 h = next_ifile(curr_ifile); 355 if (h != NULL_IFILE) 356 { 357 s = unquote_file(get_filename(h)); 358 ap_str(s); 359 free(s); 360 } else 361 ap_quest(); 362 break; 363 } 364 } 365 366 /* 367 * Skip a false conditional. 368 * When a false condition is found (either a false IF or the ELSE part 369 * of a true IF), this routine scans the prototype string to decide 370 * where to resume parsing the string. 371 * We must keep track of nested IFs and skip them properly. 372 */ 373 static char * 374 skipcond(p) 375 register char *p; 376 { 377 register int iflevel; 378 379 /* 380 * We came in here after processing a ? or :, 381 * so we start nested one level deep. 382 */ 383 iflevel = 1; 384 385 for (;;) switch (*++p) 386 { 387 case '?': 388 /* 389 * Start of a nested IF. 390 */ 391 iflevel++; 392 break; 393 case ':': 394 /* 395 * Else. 396 * If this matches the IF we came in here with, 397 * then we're done. 398 */ 399 if (iflevel == 1) 400 return (p); 401 break; 402 case '.': 403 /* 404 * Endif. 405 * If this matches the IF we came in here with, 406 * then we're done. 407 */ 408 if (--iflevel == 0) 409 return (p); 410 break; 411 case '\\': 412 /* 413 * Backslash escapes the next character. 414 */ 415 ++p; 416 break; 417 case '\0': 418 /* 419 * Whoops. Hit end of string. 420 * This is a malformed conditional, but just treat it 421 * as if all active conditionals ends here. 422 */ 423 return (p-1); 424 } 425 /*NOTREACHED*/ 426 } 427 428 /* 429 * Decode a char that represents a position on the screen. 430 */ 431 static char * 432 wherechar(p, wp) 433 char *p; 434 int *wp; 435 { 436 switch (*p) 437 { 438 case 'b': case 'd': case 'l': case 'p': case 'P': 439 switch (*++p) 440 { 441 case 't': *wp = TOP; break; 442 case 'm': *wp = MIDDLE; break; 443 case 'b': *wp = BOTTOM; break; 444 case 'B': *wp = BOTTOM_PLUS_ONE; break; 445 case 'j': *wp = adjsline(jump_sline); break; 446 default: *wp = TOP; p--; break; 447 } 448 } 449 return (p); 450 } 451 452 /* 453 * Construct a message based on a prototype string. 454 */ 455 public char * 456 pr_expand(proto, maxwidth) 457 char *proto; 458 int maxwidth; 459 { 460 register char *p; 461 register int c; 462 int where; 463 464 mp = message; 465 466 if (*proto == '\0') 467 return (""); 468 469 for (p = proto; *p != '\0'; p++) 470 { 471 switch (*p) 472 { 473 default: /* Just put the character in the message */ 474 ap_char(*p); 475 break; 476 case '\\': /* Backslash escapes the next character */ 477 p++; 478 ap_char(*p); 479 break; 480 case '?': /* Conditional (IF) */ 481 if ((c = *++p) == '\0') 482 --p; 483 else 484 { 485 where = 0; 486 p = wherechar(p, &where); 487 if (!cond(c, where)) 488 p = skipcond(p); 489 } 490 break; 491 case ':': /* ELSE */ 492 p = skipcond(p); 493 break; 494 case '.': /* ENDIF */ 495 break; 496 case '%': /* Percent escape */ 497 if ((c = *++p) == '\0') 498 --p; 499 else 500 { 501 where = 0; 502 p = wherechar(p, &where); 503 protochar(c, where, 504 #if EDITOR 505 (proto == editproto)); 506 #else 507 0); 508 #endif 509 510 } 511 break; 512 } 513 } 514 515 if (mp == message) 516 return (NULL); 517 if (maxwidth > 0 && mp >= message + maxwidth) 518 { 519 /* 520 * Message is too long. 521 * Return just the final portion of it. 522 */ 523 return (mp - maxwidth); 524 } 525 return (message); 526 } 527 528 /* 529 * Return a message suitable for printing by the "=" command. 530 */ 531 public char * 532 eq_message() 533 { 534 return (pr_expand(eqproto, 0)); 535 } 536 537 /* 538 * Return a prompt. 539 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc. 540 * If we can't come up with an appropriate prompt, return NULL 541 * and the caller will prompt with a colon. 542 */ 543 public char * 544 pr_string() 545 { 546 char *prompt; 547 548 prompt = pr_expand((ch_getflags() & CH_HELPFILE) ? 549 hproto : prproto[pr_type], 550 sc_width-so_s_width-so_e_width-2); 551 new_file = 0; 552 return (prompt); 553 } 554 555 /* 556 * Return a message suitable for printing while waiting in the F command. 557 */ 558 public char * 559 wait_message() 560 { 561 return (pr_expand(wproto, sc_width-so_s_width-so_e_width-2)); 562 } 563