1 /* 2 * Copyright (C) 1984-2012 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 IFILE curr_ifile; 33 #if EDITOR 34 extern char *editor; 35 extern char *editproto; 36 #endif 37 38 /* 39 * Prototypes for the three flavors of prompts. 40 * These strings are expanded by pr_expand(). 41 */ 42 static constant char s_proto[] = 43 "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x..%t"; 44 static constant char m_proto[] = 45 "?f%f .?m(%T %i of %m) .?e(END) ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t"; 46 static constant char M_proto[] = 47 "?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"; 48 static constant char e_proto[] = 49 "?f%f .?m(%T %i of %m) .?ltlines %lt-%lb?L/%L. .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t"; 50 static constant char h_proto[] = 51 "HELP -- ?eEND -- Press g to see it again:Press RETURN for more., or q when done"; 52 static constant char w_proto[] = 53 "Waiting for data"; 54 55 public char *prproto[3]; 56 public char constant *eqproto = e_proto; 57 public char constant *hproto = h_proto; 58 public char constant *wproto = w_proto; 59 60 static char message[PROMPT_SIZE]; 61 static char *mp; 62 63 /* 64 * Initialize the prompt prototype strings. 65 */ 66 public void 67 init_prompt() 68 { 69 prproto[0] = save(s_proto); 70 prproto[1] = save(m_proto); 71 prproto[2] = save(M_proto); 72 eqproto = save(e_proto); 73 hproto = save(h_proto); 74 wproto = save(w_proto); 75 } 76 77 /* 78 * Append a string to the end of the message. 79 */ 80 static void 81 ap_str(s) 82 char *s; 83 { 84 int len; 85 86 len = strlen(s); 87 if (mp + len >= message + PROMPT_SIZE) 88 len = message + PROMPT_SIZE - mp - 1; 89 strncpy(mp, s, len); 90 mp += len; 91 *mp = '\0'; 92 } 93 94 /* 95 * Append a character to the end of the message. 96 */ 97 static void 98 ap_char(c) 99 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 112 ap_pos(pos) 113 POSITION pos; 114 { 115 char buf[INT_STRLEN_BOUND(pos) + 2]; 116 117 postoa(pos, buf, sizeof(buf)); 118 ap_str(buf); 119 } 120 121 /* 122 * Append a line number to the end of the message. 123 */ 124 static void 125 ap_linenum(linenum) 126 LINENUM linenum; 127 { 128 char buf[INT_STRLEN_BOUND(linenum) + 2]; 129 130 linenumtoa(linenum, buf, sizeof(buf)); 131 ap_str(buf); 132 } 133 134 /* 135 * Append an integer to the end of the message. 136 */ 137 static void 138 ap_int(num) 139 int num; 140 { 141 char buf[INT_STRLEN_BOUND(num) + 2]; 142 143 inttoa(num, buf, sizeof(buf)); 144 ap_str(buf); 145 } 146 147 /* 148 * Append a question mark to the end of the message. 149 */ 150 static void 151 ap_quest() 152 { 153 ap_str("?"); 154 } 155 156 /* 157 * Return the "current" byte offset in the file. 158 */ 159 static POSITION 160 curr_byte(where) 161 int where; 162 { 163 POSITION pos; 164 165 pos = position(where); 166 while (pos == NULL_POSITION && where >= 0 && where < sc_height-1) 167 pos = position(++where); 168 if (pos == NULL_POSITION) 169 pos = ch_length(); 170 return (pos); 171 } 172 173 /* 174 * Return the value of a prototype conditional. 175 * A prototype string may include conditionals which consist of a 176 * question mark followed by a single letter. 177 * Here we decode that letter and return the appropriate boolean value. 178 */ 179 static int 180 cond(c, where) 181 char c; 182 int where; 183 { 184 POSITION len; 185 186 switch (c) 187 { 188 case 'a': /* Anything in the message yet? */ 189 return (mp > message); 190 case 'b': /* Current byte offset known? */ 191 return (curr_byte(where) != NULL_POSITION); 192 case 'c': 193 return (hshift != 0); 194 case 'e': /* At end of file? */ 195 return (eof_displayed()); 196 case 'f': /* Filename known? */ 197 return (strcmp(get_filename(curr_ifile), "-") != 0); 198 case 'l': /* Line number known? */ 199 case 'd': /* Same as l */ 200 return (linenums); 201 case 'L': /* Final line number known? */ 202 case 'D': /* Final page number known? */ 203 return (linenums && ch_length() != NULL_POSITION); 204 case 'm': /* More than one file? */ 205 #if TAGS 206 return (ntags() ? (ntags() > 1) : (nifile() > 1)); 207 #else 208 return (nifile() > 1); 209 #endif 210 case 'n': /* First prompt in a new file? */ 211 #if TAGS 212 return (ntags() ? 1 : new_file); 213 #else 214 return (new_file); 215 #endif 216 case 'p': /* Percent into file (bytes) known? */ 217 return (curr_byte(where) != NULL_POSITION && 218 ch_length() > 0); 219 case 'P': /* Percent into file (lines) known? */ 220 return (currline(where) != 0 && 221 (len = ch_length()) > 0 && 222 find_linenum(len) != 0); 223 case 's': /* Size of file known? */ 224 case 'B': 225 return (ch_length() != NULL_POSITION); 226 case 'x': /* Is there a "next" file? */ 227 #if TAGS 228 if (ntags()) 229 return (0); 230 #endif 231 return (next_ifile(curr_ifile) != NULL_IFILE); 232 } 233 return (0); 234 } 235 236 /* 237 * Decode a "percent" prototype character. 238 * A prototype string may include various "percent" escapes; 239 * that is, a percent sign followed by a single letter. 240 * Here we decode that letter and take the appropriate action, 241 * usually by appending something to the message being built. 242 */ 243 static void 244 protochar(c, where, iseditproto) 245 int c; 246 int where; 247 int iseditproto; 248 { 249 POSITION pos; 250 POSITION len; 251 int n; 252 LINENUM linenum; 253 LINENUM last_linenum; 254 IFILE h; 255 256 #undef PAGE_NUM 257 #define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - 1)) + 1) 258 259 switch (c) 260 { 261 case 'b': /* Current byte offset */ 262 pos = curr_byte(where); 263 if (pos != NULL_POSITION) 264 ap_pos(pos); 265 else 266 ap_quest(); 267 break; 268 case 'c': 269 ap_int(hshift); 270 break; 271 case 'd': /* Current page number */ 272 linenum = currline(where); 273 if (linenum > 0 && sc_height > 1) 274 ap_linenum(PAGE_NUM(linenum)); 275 else 276 ap_quest(); 277 break; 278 case 'D': /* Final page number */ 279 /* Find the page number of the last byte in the file (len-1). */ 280 len = ch_length(); 281 if (len == NULL_POSITION) 282 ap_quest(); 283 else if (len == 0) 284 /* An empty file has no pages. */ 285 ap_linenum(0); 286 else 287 { 288 linenum = find_linenum(len - 1); 289 if (linenum <= 0) 290 ap_quest(); 291 else 292 ap_linenum(PAGE_NUM(linenum)); 293 } 294 break; 295 #if EDITOR 296 case 'E': /* Editor name */ 297 ap_str(editor); 298 break; 299 #endif 300 case 'f': /* File name */ 301 ap_str(get_filename(curr_ifile)); 302 break; 303 case 'F': /* Last component of file name */ 304 ap_str(last_component(get_filename(curr_ifile))); 305 break; 306 case 'i': /* Index into list of files */ 307 #if TAGS 308 if (ntags()) 309 ap_int(curr_tag()); 310 else 311 #endif 312 ap_int(get_index(curr_ifile)); 313 break; 314 case 'l': /* Current line number */ 315 linenum = currline(where); 316 if (linenum != 0) 317 ap_linenum(linenum); 318 else 319 ap_quest(); 320 break; 321 case 'L': /* Final line number */ 322 len = ch_length(); 323 if (len == NULL_POSITION || len == ch_zero() || 324 (linenum = find_linenum(len)) <= 0) 325 ap_quest(); 326 else 327 ap_linenum(linenum-1); 328 break; 329 case 'm': /* Number of files */ 330 #if TAGS 331 n = ntags(); 332 if (n) 333 ap_int(n); 334 else 335 #endif 336 ap_int(nifile()); 337 break; 338 case 'p': /* Percent into file (bytes) */ 339 pos = curr_byte(where); 340 len = ch_length(); 341 if (pos != NULL_POSITION && len > 0) 342 ap_int(percentage(pos,len)); 343 else 344 ap_quest(); 345 break; 346 case 'P': /* Percent into file (lines) */ 347 linenum = currline(where); 348 if (linenum == 0 || 349 (len = ch_length()) == NULL_POSITION || len == ch_zero() || 350 (last_linenum = find_linenum(len)) <= 0) 351 ap_quest(); 352 else 353 ap_int(percentage(linenum, last_linenum)); 354 break; 355 case 's': /* Size of file */ 356 case 'B': 357 len = ch_length(); 358 if (len != NULL_POSITION) 359 ap_pos(len); 360 else 361 ap_quest(); 362 break; 363 case 't': /* Truncate trailing spaces in the message */ 364 while (mp > message && mp[-1] == ' ') 365 mp--; 366 *mp = '\0'; 367 break; 368 case 'T': /* Type of list */ 369 #if TAGS 370 if (ntags()) 371 ap_str("tag"); 372 else 373 #endif 374 ap_str("file"); 375 break; 376 case 'x': /* Name of next file */ 377 h = next_ifile(curr_ifile); 378 if (h != NULL_IFILE) 379 ap_str(get_filename(h)); 380 else 381 ap_quest(); 382 break; 383 } 384 } 385 386 /* 387 * Skip a false conditional. 388 * When a false condition is found (either a false IF or the ELSE part 389 * of a true IF), this routine scans the prototype string to decide 390 * where to resume parsing the string. 391 * We must keep track of nested IFs and skip them properly. 392 */ 393 static constant char * 394 skipcond(p) 395 register constant char *p; 396 { 397 register int iflevel; 398 399 /* 400 * We came in here after processing a ? or :, 401 * so we start nested one level deep. 402 */ 403 iflevel = 1; 404 405 for (;;) switch (*++p) 406 { 407 case '?': 408 /* 409 * Start of a nested IF. 410 */ 411 iflevel++; 412 break; 413 case ':': 414 /* 415 * Else. 416 * If this matches the IF we came in here with, 417 * then we're done. 418 */ 419 if (iflevel == 1) 420 return (p); 421 break; 422 case '.': 423 /* 424 * Endif. 425 * If this matches the IF we came in here with, 426 * then we're done. 427 */ 428 if (--iflevel == 0) 429 return (p); 430 break; 431 case '\\': 432 /* 433 * Backslash escapes the next character. 434 */ 435 ++p; 436 break; 437 case '\0': 438 /* 439 * Whoops. Hit end of string. 440 * This is a malformed conditional, but just treat it 441 * as if all active conditionals ends here. 442 */ 443 return (p-1); 444 } 445 /*NOTREACHED*/ 446 } 447 448 /* 449 * Decode a char that represents a position on the screen. 450 */ 451 static constant char * 452 wherechar(p, wp) 453 char constant *p; 454 int *wp; 455 { 456 switch (*p) 457 { 458 case 'b': case 'd': case 'l': case 'p': case 'P': 459 switch (*++p) 460 { 461 case 't': *wp = TOP; break; 462 case 'm': *wp = MIDDLE; break; 463 case 'b': *wp = BOTTOM; break; 464 case 'B': *wp = BOTTOM_PLUS_ONE; break; 465 case 'j': *wp = adjsline(jump_sline); break; 466 default: *wp = TOP; p--; break; 467 } 468 } 469 return (p); 470 } 471 472 /* 473 * Construct a message based on a prototype string. 474 */ 475 public char * 476 pr_expand(proto, maxwidth) 477 constant char *proto; 478 int maxwidth; 479 { 480 register constant char *p; 481 register int c; 482 int where; 483 484 mp = message; 485 486 if (*proto == '\0') 487 return (""); 488 489 for (p = proto; *p != '\0'; p++) 490 { 491 switch (*p) 492 { 493 default: /* Just put the character in the message */ 494 ap_char(*p); 495 break; 496 case '\\': /* Backslash escapes the next character */ 497 p++; 498 ap_char(*p); 499 break; 500 case '?': /* Conditional (IF) */ 501 if ((c = *++p) == '\0') 502 --p; 503 else 504 { 505 where = 0; 506 p = wherechar(p, &where); 507 if (!cond(c, where)) 508 p = skipcond(p); 509 } 510 break; 511 case ':': /* ELSE */ 512 p = skipcond(p); 513 break; 514 case '.': /* ENDIF */ 515 break; 516 case '%': /* Percent escape */ 517 if ((c = *++p) == '\0') 518 --p; 519 else 520 { 521 where = 0; 522 p = wherechar(p, &where); 523 protochar(c, where, 524 #if EDITOR 525 (proto == editproto)); 526 #else 527 0); 528 #endif 529 530 } 531 break; 532 } 533 } 534 535 if (mp == message) 536 return (""); 537 if (maxwidth > 0 && mp >= message + maxwidth) 538 { 539 /* 540 * Message is too long. 541 * Return just the final portion of it. 542 */ 543 return (mp - maxwidth); 544 } 545 return (message); 546 } 547 548 /* 549 * Return a message suitable for printing by the "=" command. 550 */ 551 public char * 552 eq_message() 553 { 554 return (pr_expand(eqproto, 0)); 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 char * 564 pr_string() 565 { 566 char *prompt; 567 int type; 568 569 type = (!less_is_more) ? pr_type : pr_type ? 0 : 1; 570 prompt = pr_expand((ch_getflags() & CH_HELPFILE) ? 571 hproto : prproto[type], 572 sc_width-so_s_width-so_e_width-2); 573 new_file = 0; 574 return (prompt); 575 } 576 577 /* 578 * Return a message suitable for printing while waiting in the F command. 579 */ 580 public char * 581 wait_message() 582 { 583 return (pr_expand(wproto, sc_width-so_s_width-so_e_width-2)); 584 } 585