1 /* $FreeBSD$ */ 2 /* 3 * Copyright (C) 1984-2004 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) + 2]; 118 119 postoa(pos, buf); 120 ap_str(buf); 121 } 122 123 /* 124 * Append a line number to the end of the message. 125 */ 126 static void 127 ap_linenum(linenum) 128 LINENUM linenum; 129 { 130 char buf[INT_STRLEN_BOUND(linenum) + 2]; 131 132 linenumtoa(linenum, buf); 133 ap_str(buf); 134 } 135 136 /* 137 * Append an integer to the end of the message. 138 */ 139 static void 140 ap_int(num) 141 int num; 142 { 143 char buf[INT_STRLEN_BOUND(num) + 2]; 144 145 inttoa(num, buf); 146 ap_str(buf); 147 } 148 149 /* 150 * Append a question mark to the end of the message. 151 */ 152 static void 153 ap_quest() 154 { 155 ap_str("?"); 156 } 157 158 /* 159 * Return the "current" byte offset in the file. 160 */ 161 static POSITION 162 curr_byte(where) 163 int where; 164 { 165 POSITION pos; 166 167 pos = position(where); 168 while (pos == NULL_POSITION && where >= 0 && where < sc_height-1) 169 pos = position(++where); 170 if (pos == NULL_POSITION) 171 pos = ch_length(); 172 return (pos); 173 } 174 175 /* 176 * Return the value of a prototype conditional. 177 * A prototype string may include conditionals which consist of a 178 * question mark followed by a single letter. 179 * Here we decode that letter and return the appropriate boolean value. 180 */ 181 static int 182 cond(c, where) 183 char c; 184 int where; 185 { 186 POSITION len; 187 188 switch (c) 189 { 190 case 'a': /* Anything in the message yet? */ 191 return (mp > message); 192 case 'b': /* Current byte offset known? */ 193 return (curr_byte(where) != NULL_POSITION); 194 case 'c': 195 return (hshift != 0); 196 case 'e': /* At end of file? */ 197 return (hit_eof); 198 case 'f': /* Filename known? */ 199 return (strcmp(get_filename(curr_ifile), "-") != 0); 200 case 'l': /* Line number known? */ 201 case 'd': /* Same as l */ 202 return (linenums); 203 case 'L': /* Final line number known? */ 204 case 'D': /* Final page number known? */ 205 return (linenums && ch_length() != NULL_POSITION); 206 case 'm': /* More than one file? */ 207 #if TAGS 208 return (ntags() ? (ntags() > 1) : (nifile() > 1)); 209 #else 210 return (nifile() > 1); 211 #endif 212 case 'n': /* First prompt in a new file? */ 213 #if TAGS 214 return (ntags() ? 1 : new_file); 215 #else 216 return (new_file); 217 #endif 218 case 'p': /* Percent into file (bytes) known? */ 219 return (curr_byte(where) != NULL_POSITION && 220 ch_length() > 0); 221 case 'P': /* Percent into file (lines) known? */ 222 return (currline(where) != 0 && 223 (len = ch_length()) > 0 && 224 find_linenum(len) != 0); 225 case 's': /* Size of file known? */ 226 case 'B': 227 return (ch_length() != NULL_POSITION); 228 case 'x': /* Is there a "next" file? */ 229 #if TAGS 230 if (ntags()) 231 return (0); 232 #endif 233 return (next_ifile(curr_ifile) != NULL_IFILE); 234 } 235 return (0); 236 } 237 238 /* 239 * Decode a "percent" prototype character. 240 * A prototype string may include various "percent" escapes; 241 * that is, a percent sign followed by a single letter. 242 * Here we decode that letter and take the appropriate action, 243 * usually by appending something to the message being built. 244 */ 245 static void 246 protochar(c, where, iseditproto) 247 int c; 248 int where; 249 int iseditproto; 250 { 251 POSITION pos; 252 POSITION len; 253 int n; 254 LINENUM linenum; 255 LINENUM last_linenum; 256 IFILE h; 257 258 #undef PAGE_NUM 259 #define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - 1)) + 1) 260 261 switch (c) 262 { 263 case 'b': /* Current byte offset */ 264 pos = curr_byte(where); 265 if (pos != NULL_POSITION) 266 ap_pos(pos); 267 else 268 ap_quest(); 269 break; 270 case 'c': 271 ap_int(hshift); 272 break; 273 case 'd': /* Current page number */ 274 linenum = currline(where); 275 if (linenum > 0 && sc_height > 1) 276 ap_linenum(PAGE_NUM(linenum)); 277 else 278 ap_quest(); 279 break; 280 case 'D': /* Final page number */ 281 /* Find the page number of the last byte in the file (len-1). */ 282 len = ch_length(); 283 if (len == NULL_POSITION) 284 ap_quest(); 285 else if (len == 0) 286 /* An empty file has no pages. */ 287 ap_linenum(0); 288 else 289 { 290 linenum = find_linenum(len - 1); 291 if (linenum <= 0) 292 ap_quest(); 293 else 294 ap_linenum(PAGE_NUM(linenum)); 295 } 296 break; 297 #if EDITOR 298 case 'E': /* Editor name */ 299 ap_str(editor); 300 break; 301 #endif 302 case 'f': /* File name */ 303 ap_str(get_filename(curr_ifile)); 304 break; 305 case 'i': /* Index into list of files */ 306 #if TAGS 307 if (ntags()) 308 ap_int(curr_tag()); 309 else 310 #endif 311 ap_int(get_index(curr_ifile)); 312 break; 313 case 'l': /* Current line number */ 314 linenum = currline(where); 315 if (linenum != 0) 316 ap_linenum(linenum); 317 else 318 ap_quest(); 319 break; 320 case 'L': /* Final line number */ 321 len = ch_length(); 322 if (len == NULL_POSITION || len == ch_zero() || 323 (linenum = find_linenum(len)) <= 0) 324 ap_quest(); 325 else 326 ap_linenum(linenum-1); 327 break; 328 case 'm': /* Number of files */ 329 #if TAGS 330 n = ntags(); 331 if (n) 332 ap_int(n); 333 else 334 #endif 335 ap_int(nifile()); 336 break; 337 case 'p': /* Percent into file (bytes) */ 338 pos = curr_byte(where); 339 len = ch_length(); 340 if (pos != NULL_POSITION && len > 0) 341 ap_int(percentage(pos,len)); 342 else 343 ap_quest(); 344 break; 345 case 'P': /* Percent into file (lines) */ 346 linenum = currline(where); 347 if (linenum == 0 || 348 (len = ch_length()) == NULL_POSITION || len == ch_zero() || 349 (last_linenum = find_linenum(len)) <= 0) 350 ap_quest(); 351 else 352 ap_int(percentage(linenum, last_linenum)); 353 break; 354 case 's': /* Size of file */ 355 case 'B': 356 len = ch_length(); 357 if (len != NULL_POSITION) 358 ap_pos(len); 359 else 360 ap_quest(); 361 break; 362 case 't': /* Truncate trailing spaces in the message */ 363 while (mp > message && mp[-1] == ' ') 364 mp--; 365 break; 366 case 'T': /* Type of list */ 367 #if TAGS 368 if (ntags()) 369 ap_str("tag"); 370 else 371 #endif 372 ap_str("file"); 373 break; 374 case 'x': /* Name of next file */ 375 h = next_ifile(curr_ifile); 376 if (h != NULL_IFILE) 377 ap_str(get_filename(h)); 378 else 379 ap_quest(); 380 break; 381 } 382 } 383 384 /* 385 * Skip a false conditional. 386 * When a false condition is found (either a false IF or the ELSE part 387 * of a true IF), this routine scans the prototype string to decide 388 * where to resume parsing the string. 389 * We must keep track of nested IFs and skip them properly. 390 */ 391 static char * 392 skipcond(p) 393 register char *p; 394 { 395 register int iflevel; 396 397 /* 398 * We came in here after processing a ? or :, 399 * so we start nested one level deep. 400 */ 401 iflevel = 1; 402 403 for (;;) switch (*++p) 404 { 405 case '?': 406 /* 407 * Start of a nested IF. 408 */ 409 iflevel++; 410 break; 411 case ':': 412 /* 413 * Else. 414 * If this matches the IF we came in here with, 415 * then we're done. 416 */ 417 if (iflevel == 1) 418 return (p); 419 break; 420 case '.': 421 /* 422 * Endif. 423 * If this matches the IF we came in here with, 424 * then we're done. 425 */ 426 if (--iflevel == 0) 427 return (p); 428 break; 429 case '\\': 430 /* 431 * Backslash escapes the next character. 432 */ 433 ++p; 434 break; 435 case '\0': 436 /* 437 * Whoops. Hit end of string. 438 * This is a malformed conditional, but just treat it 439 * as if all active conditionals ends here. 440 */ 441 return (p-1); 442 } 443 /*NOTREACHED*/ 444 } 445 446 /* 447 * Decode a char that represents a position on the screen. 448 */ 449 static char * 450 wherechar(p, wp) 451 char *p; 452 int *wp; 453 { 454 switch (*p) 455 { 456 case 'b': case 'd': case 'l': case 'p': case 'P': 457 switch (*++p) 458 { 459 case 't': *wp = TOP; break; 460 case 'm': *wp = MIDDLE; break; 461 case 'b': *wp = BOTTOM; break; 462 case 'B': *wp = BOTTOM_PLUS_ONE; break; 463 case 'j': *wp = adjsline(jump_sline); break; 464 default: *wp = TOP; p--; break; 465 } 466 } 467 return (p); 468 } 469 470 /* 471 * Construct a message based on a prototype string. 472 */ 473 public char * 474 pr_expand(proto, maxwidth) 475 char *proto; 476 int maxwidth; 477 { 478 register char *p; 479 register int c; 480 int where; 481 482 mp = message; 483 484 if (*proto == '\0') 485 return (""); 486 487 for (p = proto; *p != '\0'; p++) 488 { 489 switch (*p) 490 { 491 default: /* Just put the character in the message */ 492 ap_char(*p); 493 break; 494 case '\\': /* Backslash escapes the next character */ 495 p++; 496 ap_char(*p); 497 break; 498 case '?': /* Conditional (IF) */ 499 if ((c = *++p) == '\0') 500 --p; 501 else 502 { 503 where = 0; 504 p = wherechar(p, &where); 505 if (!cond(c, where)) 506 p = skipcond(p); 507 } 508 break; 509 case ':': /* ELSE */ 510 p = skipcond(p); 511 break; 512 case '.': /* ENDIF */ 513 break; 514 case '%': /* Percent escape */ 515 if ((c = *++p) == '\0') 516 --p; 517 else 518 { 519 where = 0; 520 p = wherechar(p, &where); 521 protochar(c, where, 522 #if EDITOR 523 (proto == editproto)); 524 #else 525 0); 526 #endif 527 528 } 529 break; 530 } 531 } 532 533 if (mp == message) 534 return (""); 535 if (maxwidth > 0 && mp >= message + maxwidth) 536 { 537 /* 538 * Message is too long. 539 * Return just the final portion of it. 540 */ 541 return (mp - maxwidth); 542 } 543 return (message); 544 } 545 546 /* 547 * Return a message suitable for printing by the "=" command. 548 */ 549 public char * 550 eq_message() 551 { 552 return (pr_expand(eqproto, 0)); 553 } 554 555 /* 556 * Return a prompt. 557 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc. 558 * If we can't come up with an appropriate prompt, return NULL 559 * and the caller will prompt with a colon. 560 */ 561 public char * 562 pr_string() 563 { 564 char *prompt; 565 566 prompt = pr_expand((ch_getflags() & CH_HELPFILE) ? 567 hproto : prproto[pr_type], 568 sc_width-so_s_width-so_e_width-2); 569 new_file = 0; 570 return (prompt); 571 } 572 573 /* 574 * Return a message suitable for printing while waiting in the F command. 575 */ 576 public char * 577 wait_message() 578 { 579 return (pr_expand(wproto, sc_width-so_s_width-so_e_width-2)); 580 } 581