1 /* $NetBSD: display.c,v 1.1.1.1 2016/01/14 00:11:29 christos Exp $ */ 2 3 /* display.c -- How to display Info windows. 4 Id: display.c,v 1.7 2004/04/11 17:56:45 karl Exp 5 6 Copyright (C) 1993, 1997, 2003, 2004 Free Software Foundation, Inc. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2, or (at your option) 11 any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 21 22 Originally written by Brian Fox (bfox@ai.mit.edu). */ 23 24 #include "info.h" 25 #include "display.h" 26 27 extern int info_any_buffered_input_p (void); /* Found in session.c. */ 28 29 static void free_display (DISPLAY_LINE **display); 30 static DISPLAY_LINE **make_display (int width, int height); 31 32 void handle_tag (char *tag); 33 void handle_tag_start (char *tag); 34 void handle_tag_end (char *tag); 35 36 /* An array of display lines which tell us what is currently visible on 37 the display. */ 38 DISPLAY_LINE **the_display = (DISPLAY_LINE **)NULL; 39 40 /* Non-zero means do no output. */ 41 int display_inhibited = 0; 42 43 /* Initialize THE_DISPLAY to WIDTH and HEIGHT, with nothing in it. */ 44 void 45 display_initialize_display (int width, int height) 46 { 47 free_display (the_display); 48 the_display = make_display (width, height); 49 display_clear_display (the_display); 50 } 51 52 /* Clear all of the lines in DISPLAY making the screen blank. */ 53 void 54 display_clear_display (DISPLAY_LINE **display) 55 { 56 register int i; 57 58 for (i = 0; display[i]; i++) 59 { 60 display[i]->text[0] = '\0'; 61 display[i]->textlen = 0; 62 display[i]->inverse = 0; 63 } 64 } 65 66 /* Non-zero if we didn't completely redisplay a window. */ 67 int display_was_interrupted_p = 0; 68 69 /* Update the windows pointed to by WINDOW in the_display. This actually 70 writes the text on the screen. */ 71 void 72 display_update_display (WINDOW *window) 73 { 74 register WINDOW *win; 75 76 display_was_interrupted_p = 0; 77 78 /* For every window in the list, check contents against the display. */ 79 for (win = window; win; win = win->next) 80 { 81 /* Only re-display visible windows which need updating. */ 82 if (((win->flags & W_WindowVisible) == 0) || 83 ((win->flags & W_UpdateWindow) == 0) || 84 (win->height == 0)) 85 continue; 86 87 display_update_one_window (win); 88 if (display_was_interrupted_p) 89 break; 90 } 91 92 /* Always update the echo area. */ 93 display_update_one_window (the_echo_area); 94 } 95 96 void 97 handle_tag_start (char *tag) 98 { 99 /* TODO really handle this tag. */ 100 return; 101 } 102 103 void 104 handle_tag_end (char *tag) 105 { 106 /* TODO really handle this tag. */ 107 return; 108 } 109 110 void 111 handle_tag (char *tag) 112 { 113 if (tag[0] == '/') 114 { 115 tag++; 116 handle_tag_end (tag); 117 } 118 else 119 handle_tag_start (tag); 120 } 121 122 /* Display WIN on the_display. Unlike display_update_display (), this 123 function only does one window. */ 124 void 125 display_update_one_window (WINDOW *win) 126 { 127 register char *nodetext; /* Current character to display. */ 128 register char *last_node_char; /* Position of the last character in node. */ 129 register int i; /* General use index. */ 130 char *printed_line; /* Buffer for a printed line. */ 131 int pl_index = 0; /* Index into PRINTED_LINE. */ 132 int line_index = 0; /* Number of lines done so far. */ 133 int pl_ignore = 0; /* How many chars use zero width on screen. */ 134 int allocated_win_width; 135 DISPLAY_LINE **display = the_display; 136 137 /* If display is inhibited, that counts as an interrupted display. */ 138 if (display_inhibited) 139 display_was_interrupted_p = 1; 140 141 /* If the window has no height, or display is inhibited, quit now. */ 142 if (!win->height || display_inhibited) 143 return; 144 145 /* If the window's first row doesn't appear in the_screen, then it 146 cannot be displayed. This can happen when the_echo_area is the 147 window to be displayed, and the screen has shrunk to less than one 148 line. */ 149 if ((win->first_row < 0) || (win->first_row > the_screen->height)) 150 return; 151 152 /* Print each line in the window into our local buffer, and then 153 check the contents of that buffer against the display. If they 154 differ, update the display. */ 155 allocated_win_width = win->width + 1; 156 printed_line = (char *)xmalloc (allocated_win_width); 157 158 if (!win->node || !win->line_starts) 159 goto done_with_node_display; 160 161 nodetext = win->line_starts[win->pagetop]; 162 last_node_char = win->node->contents + win->node->nodelen; 163 164 for (; nodetext < last_node_char; nodetext++) 165 { 166 char *rep = NULL, *rep_carried_over, rep_temp[2]; 167 int replen; 168 169 if (isprint (*nodetext)) 170 { 171 rep_temp[0] = *nodetext; 172 replen = 1; 173 rep_temp[1] = '\0'; 174 rep = rep_temp; 175 } 176 else 177 { 178 if (*nodetext == '\r' || *nodetext == '\n') 179 { 180 replen = win->width - pl_index + pl_ignore; 181 } 182 else if (*nodetext == '\0' 183 && (nodetext + 2) < last_node_char 184 && *(nodetext + 1) == '\b' 185 && *(nodetext + 2) == '[') 186 { 187 /* Found new style tag/cookie \0\b[ 188 Read until the closing tag \0\b] */ 189 int element_len = 0; 190 char *element; 191 192 /* Skip the escapes. */ 193 nodetext += 3; 194 195 while (!(*nodetext == '\0' 196 && *(nodetext + 1) == '\b' 197 && *(nodetext + 2) == ']')) 198 { 199 nodetext++; 200 element_len++; 201 } 202 203 element = (char *) malloc (element_len + 1); 204 strncpy (element, nodetext - element_len, element_len); 205 206 /* Skip the escapes. */ 207 nodetext += 2; 208 pl_ignore += element_len + 5; 209 /* Append string terminator. */ 210 element[element_len] = '\0'; 211 212 handle_tag (element); 213 214 /* Over and out */ 215 free (element); 216 217 continue; 218 } 219 else 220 { 221 rep = printed_representation (*nodetext, pl_index); 222 replen = strlen (rep); 223 } 224 } 225 226 /* Support ANSI escape sequences under -R. */ 227 if (raw_escapes_p 228 && *nodetext == '\033' 229 && nodetext[1] == '[' 230 && isdigit (nodetext[2])) 231 { 232 if (nodetext[3] == 'm') 233 pl_ignore += 4; 234 else if (isdigit (nodetext[3]) && nodetext[4] == 'm') 235 pl_ignore += 5; 236 } 237 while (pl_index + 2 >= allocated_win_width - 1) 238 { 239 allocated_win_width *= 2; 240 printed_line = (char *)xrealloc (printed_line, allocated_win_width); 241 } 242 243 /* If this character can be printed without passing the width of 244 the line, then stuff it into the line. */ 245 if (replen + pl_index < win->width + pl_ignore) 246 { 247 /* Optimize if possible. */ 248 if (replen == 1) 249 { 250 printed_line[pl_index++] = *rep; 251 } 252 else 253 { 254 for (i = 0; i < replen; i++) 255 printed_line[pl_index++] = rep[i]; 256 } 257 } 258 else 259 { 260 DISPLAY_LINE *entry; 261 262 /* If this character cannot be printed in this line, we have 263 found the end of this line as it would appear on the screen. 264 Carefully print the end of the line, and then compare. */ 265 if (*nodetext == '\n' || *nodetext == '\r' || *nodetext == '\t') 266 { 267 printed_line[pl_index] = '\0'; 268 rep_carried_over = (char *)NULL; 269 } 270 else 271 { 272 /* The printed representation of this character extends into 273 the next line. Remember the offset of the last character 274 printed out of REP so that we can carry the character over 275 to the next line. */ 276 for (i = 0; pl_index < (win->width + pl_ignore - 1);) 277 printed_line[pl_index++] = rep[i++]; 278 279 rep_carried_over = rep + i; 280 281 /* If printing the last character in this window couldn't 282 possibly cause the screen to scroll, place a backslash 283 in the rightmost column. */ 284 if (1 + line_index + win->first_row < the_screen->height) 285 { 286 if (win->flags & W_NoWrap) 287 printed_line[pl_index++] = '$'; 288 else 289 printed_line[pl_index++] = '\\'; 290 } 291 printed_line[pl_index] = '\0'; 292 } 293 294 /* We have the exact line as it should appear on the screen. 295 Check to see if this line matches the one already appearing 296 on the screen. */ 297 entry = display[line_index + win->first_row]; 298 299 /* If the screen line is inversed, then we have to clear 300 the line from the screen first. Why, I don't know. 301 (But don't do this if we have no visible entries, as can 302 happen if the window is shrunk very small.) */ 303 if ((entry && entry->inverse) 304 /* Need to erase the line if it has escape sequences. */ 305 || (raw_escapes_p && strchr (entry->text, '\033') != 0)) 306 { 307 terminal_goto_xy (0, line_index + win->first_row); 308 terminal_clear_to_eol (); 309 entry->inverse = 0; 310 entry->text[0] = '\0'; 311 entry->textlen = 0; 312 } 313 314 /* Find the offset where these lines differ. */ 315 for (i = 0; i < pl_index; i++) 316 if (printed_line[i] != entry->text[i]) 317 break; 318 319 /* If the lines are not the same length, or if they differed 320 at all, we must do some redrawing. */ 321 if ((i != pl_index) || (pl_index != entry->textlen)) 322 { 323 /* Move to the proper point on the terminal. */ 324 terminal_goto_xy (i, line_index + win->first_row); 325 326 /* If there is any text to print, print it. */ 327 if (i != pl_index) 328 terminal_put_text (printed_line + i); 329 330 /* If the printed text didn't extend all the way to the edge 331 of the window, and text was appearing between here and the 332 edge of the window, clear from here to the end of the line. */ 333 if ((pl_index < win->width + pl_ignore 334 && pl_index < entry->textlen) 335 || (entry->inverse)) 336 terminal_clear_to_eol (); 337 338 fflush (stdout); 339 340 /* Update the display text buffer. */ 341 if (strlen (printed_line) > (unsigned int) screenwidth) 342 /* printed_line[] can include more than screenwidth 343 characters if we are under -R and there are escape 344 sequences in it. However, entry->text was 345 allocated (in display_initialize_display) for 346 screenwidth characters only. */ 347 entry->text = xrealloc (entry->text, strlen (printed_line)+1); 348 strcpy (entry->text + i, printed_line + i); 349 entry->textlen = pl_index; 350 351 /* Lines showing node text are not in inverse. Only modelines 352 have that distinction. */ 353 entry->inverse = 0; 354 } 355 356 /* We have done at least one line. Increment our screen line 357 index, and check against the bottom of the window. */ 358 if (++line_index == win->height) 359 break; 360 361 /* A line has been displayed, and the screen reflects that state. 362 If there is typeahead pending, then let that typeahead be read 363 now, instead of continuing with the display. */ 364 if (info_any_buffered_input_p ()) 365 { 366 free (printed_line); 367 display_was_interrupted_p = 1; 368 return; 369 } 370 371 /* Reset PL_INDEX to the start of the line. */ 372 pl_index = 0; 373 pl_ignore = 0; /* this is computed per line */ 374 375 /* If there are characters from REP left to print, stuff them 376 into the buffer now. */ 377 if (rep_carried_over) 378 for (; rep[pl_index]; pl_index++) 379 printed_line[pl_index] = rep[pl_index]; 380 381 /* If this window has chosen not to wrap lines, skip to the end 382 of the physical line in the buffer, and start a new line here. */ 383 if (pl_index && (win->flags & W_NoWrap)) 384 { 385 char *begin; 386 387 pl_index = 0; 388 printed_line[0] = '\0'; 389 390 begin = nodetext; 391 392 while ((nodetext < last_node_char) && (*nodetext != '\n')) 393 nodetext++; 394 } 395 } 396 } 397 398 done_with_node_display: 399 /* We have reached the end of the node or the end of the window. If it 400 is the end of the node, then clear the lines of the window from here 401 to the end of the window. */ 402 for (; line_index < win->height; line_index++) 403 { 404 DISPLAY_LINE *entry = display[line_index + win->first_row]; 405 406 /* If this line has text on it then make it go away. */ 407 if (entry && entry->textlen) 408 { 409 entry->textlen = 0; 410 entry->text[0] = '\0'; 411 412 terminal_goto_xy (0, line_index + win->first_row); 413 terminal_clear_to_eol (); 414 } 415 } 416 417 /* Finally, if this window has a modeline it might need to be redisplayed. 418 Check the window's modeline against the one in the display, and update 419 if necessary. */ 420 if ((win->flags & W_InhibitMode) == 0) 421 { 422 window_make_modeline (win); 423 line_index = win->first_row + win->height; 424 425 /* This display line must both be in inverse, and have the same 426 contents. */ 427 if ((!display[line_index]->inverse) || 428 (strcmp (display[line_index]->text, win->modeline) != 0)) 429 { 430 terminal_goto_xy (0, line_index); 431 terminal_begin_inverse (); 432 terminal_put_text (win->modeline); 433 terminal_end_inverse (); 434 strcpy (display[line_index]->text, win->modeline); 435 display[line_index]->inverse = 1; 436 display[line_index]->textlen = strlen (win->modeline); 437 fflush (stdout); 438 } 439 } 440 441 /* Okay, this window doesn't need updating anymore. */ 442 win->flags &= ~W_UpdateWindow; 443 free (printed_line); 444 fflush (stdout); 445 } 446 447 /* Scroll the region of the_display starting at START, ending at END, and 448 moving the lines AMOUNT lines. If AMOUNT is less than zero, the lines 449 are moved up in the screen, otherwise down. Actually, it is possible 450 for no scrolling to take place in the case that the terminal doesn't 451 support it. This doesn't matter to us. */ 452 void 453 display_scroll_display (int start, int end, int amount) 454 { 455 register int i, last; 456 DISPLAY_LINE *temp; 457 458 /* If this terminal cannot do scrolling, give up now. */ 459 if (!terminal_can_scroll) 460 return; 461 462 /* If there isn't anything displayed on the screen because it is too 463 small, quit now. */ 464 if (!the_display[0]) 465 return; 466 467 /* If there is typeahead pending, then don't actually do any scrolling. */ 468 if (info_any_buffered_input_p ()) 469 return; 470 471 /* Do it on the screen. */ 472 terminal_scroll_terminal (start, end, amount); 473 474 /* Now do it in the display buffer so our contents match the screen. */ 475 if (amount > 0) 476 { 477 last = end + amount; 478 479 /* Shift the lines to scroll right into place. */ 480 for (i = 0; i < (end - start); i++) 481 { 482 temp = the_display[last - i]; 483 the_display[last - i] = the_display[end - i]; 484 the_display[end - i] = temp; 485 } 486 487 /* The lines have been shifted down in the buffer. Clear all of the 488 lines that were vacated. */ 489 for (i = start; i != (start + amount); i++) 490 { 491 the_display[i]->text[0] = '\0'; 492 the_display[i]->textlen = 0; 493 the_display[i]->inverse = 0; 494 } 495 } 496 497 if (amount < 0) 498 { 499 last = start + amount; 500 for (i = 0; i < (end - start); i++) 501 { 502 temp = the_display[last + i]; 503 the_display[last + i] = the_display[start + i]; 504 the_display[start + i] = temp; 505 } 506 507 /* The lines have been shifted up in the buffer. Clear all of the 508 lines that are left over. */ 509 for (i = end + amount; i != end; i++) 510 { 511 the_display[i]->text[0] = '\0'; 512 the_display[i]->textlen = 0; 513 the_display[i]->inverse = 0; 514 } 515 } 516 } 517 518 /* Try to scroll lines in WINDOW. OLD_PAGETOP is the pagetop of WINDOW before 519 having had its line starts recalculated. OLD_STARTS is the list of line 520 starts that used to appear in this window. OLD_COUNT is the number of lines 521 that appear in the OLD_STARTS array. */ 522 void 523 display_scroll_line_starts (WINDOW *window, int old_pagetop, 524 char **old_starts, int old_count) 525 { 526 register int i, old, new; /* Indices into the line starts arrays. */ 527 int last_new, last_old; /* Index of the last visible line. */ 528 int old_first, new_first; /* Index of the first changed line. */ 529 int unchanged_at_top = 0; 530 int already_scrolled = 0; 531 532 /* Locate the first line which was displayed on the old window. */ 533 old_first = old_pagetop; 534 new_first = window->pagetop; 535 536 /* Find the last line currently visible in this window. */ 537 last_new = window->pagetop + (window->height - 1); 538 if (last_new > window->line_count) 539 last_new = window->line_count - 1; 540 541 /* Find the last line which used to be currently visible in this window. */ 542 last_old = old_pagetop + (window->height - 1); 543 if (last_old > old_count) 544 last_old = old_count - 1; 545 546 for (old = old_first, new = new_first; 547 old < last_old && new < last_new; 548 old++, new++) 549 if (old_starts[old] != window->line_starts[new]) 550 break; 551 else 552 unchanged_at_top++; 553 554 /* Loop through the old lines looking for a match in the new lines. */ 555 for (old = old_first + unchanged_at_top; old < last_old; old++) 556 { 557 for (new = new_first; new < last_new; new++) 558 if (old_starts[old] == window->line_starts[new]) 559 { 560 /* Find the extent of the matching lines. */ 561 for (i = 0; (old + i) < last_old; i++) 562 if (old_starts[old + i] != window->line_starts[new + i]) 563 break; 564 565 /* Scroll these lines if there are enough of them. */ 566 { 567 int start, end, amount; 568 569 start = (window->first_row 570 + ((old + already_scrolled) - old_pagetop)); 571 amount = new - (old + already_scrolled); 572 end = window->first_row + window->height; 573 574 /* If we are shifting the block of lines down, then the last 575 AMOUNT lines will become invisible. Thus, don't bother 576 scrolling them. */ 577 if (amount > 0) 578 end -= amount; 579 580 if ((end - start) > 0) 581 { 582 display_scroll_display (start, end, amount); 583 584 /* Some lines have been scrolled. Simulate the scrolling 585 by offsetting the value of the old index. */ 586 old += i; 587 already_scrolled += amount; 588 } 589 } 590 } 591 } 592 } 593 594 /* Move the screen cursor to directly over the current character in WINDOW. */ 595 void 596 display_cursor_at_point (WINDOW *window) 597 { 598 int vpos, hpos; 599 600 vpos = window_line_of_point (window) - window->pagetop + window->first_row; 601 hpos = window_get_cursor_column (window); 602 terminal_goto_xy (hpos, vpos); 603 fflush (stdout); 604 } 605 606 /* **************************************************************** */ 607 /* */ 608 /* Functions Static to this File */ 609 /* */ 610 /* **************************************************************** */ 611 612 /* Make a DISPLAY_LINE ** with width and height. */ 613 static DISPLAY_LINE ** 614 make_display (int width, int height) 615 { 616 register int i; 617 DISPLAY_LINE **display; 618 619 display = (DISPLAY_LINE **)xmalloc ((1 + height) * sizeof (DISPLAY_LINE *)); 620 621 for (i = 0; i < height; i++) 622 { 623 display[i] = (DISPLAY_LINE *)xmalloc (sizeof (DISPLAY_LINE)); 624 display[i]->text = (char *)xmalloc (1 + width); 625 display[i]->textlen = 0; 626 display[i]->inverse = 0; 627 } 628 display[i] = (DISPLAY_LINE *)NULL; 629 return (display); 630 } 631 632 /* Free the storage allocated to DISPLAY. */ 633 static void 634 free_display (DISPLAY_LINE **display) 635 { 636 register int i; 637 register DISPLAY_LINE *display_line; 638 639 if (!display) 640 return; 641 642 for (i = 0; (display_line = display[i]); i++) 643 { 644 free (display_line->text); 645 free (display_line); 646 } 647 free (display); 648 } 649