refresh.c revision 1.5
1 /* 2 * Copyright (c) 1981, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static char sccsid[] = "@(#)refresh.c 8.1 (Berkeley) 7/20/93"; 36 #endif /* not lint */ 37 38 #include <curses.h> 39 #include <string.h> 40 41 static int curwin; 42 static short ly, lx; 43 44 static void domvcur __P((int, int, int, int)); 45 static int makech __P((WINDOW *, int)); 46 static void quickch __P((WINDOW *)); 47 static void scrolln __P((WINDOW *, int, int, int, int, int)); 48 49 /* 50 * wrefresh -- 51 * Make the current screen look like "win" over the area coverd by 52 * win. 53 */ 54 int 55 wrefresh(win) 56 register WINDOW *win; 57 { 58 register __LINE *wlp; 59 register int retval; 60 register short wy; 61 int dnum; 62 63 /* Initialize loop parameters. */ 64 ly = curscr->cury; 65 lx = curscr->curx; 66 wy = 0; 67 curwin = (win == curscr); 68 69 if (!curwin) 70 for (wy = 0; wy < win->maxy; wy++) { 71 wlp = win->lines[wy]; 72 if (wlp->flags & __ISDIRTY) 73 wlp->hash = 74 __hash((char *) wlp->line, win->maxx * __LDATASIZE); 75 } 76 77 if (win->flags & __CLEAROK || curscr->flags & __CLEAROK || curwin) { 78 if ((win->flags & __FULLWIN) || curscr->flags & __CLEAROK) { 79 tputs(CL, 0, __cputchar); 80 ly = 0; 81 lx = 0; 82 if (!curwin) { 83 curscr->flags &= ~__CLEAROK; 84 curscr->cury = 0; 85 curscr->curx = 0; 86 werase(curscr); 87 } 88 __touchwin(win); 89 } 90 win->flags &= ~__CLEAROK; 91 } 92 if (!CA) { 93 if (win->curx != 0) 94 putchar('\n'); 95 if (!curwin) 96 werase(curscr); 97 } 98 #ifdef DEBUG 99 __CTRACE("wrefresh: (%0.2o): curwin = %d\n", win, curwin); 100 __CTRACE("wrefresh: \tfirstch\tlastch\n"); 101 #endif 102 103 #ifndef NOQCH 104 if ((win->flags & __FULLWIN) && !curwin) { 105 /* 106 * Invoke quickch() only if more than a quarter of the lines 107 * in the window are dirty. 108 */ 109 for (wy = 0, dnum = 0; wy < win->maxy; wy++) 110 if (win->lines[wy]->flags & (__ISDIRTY | __FORCEPAINT)) 111 dnum++; 112 if (!__noqch && dnum > (int) win->maxy / 4) 113 quickch(win); 114 } 115 #endif 116 117 #ifdef DEBUG 118 { int i, j; 119 __CTRACE("#####################################\n"); 120 for (i = 0; i < curscr->maxy; i++) { 121 __CTRACE("C: %d:", i); 122 __CTRACE(" 0x%x \n", curscr->lines[i]->hash); 123 for (j = 0; j < curscr->maxx; j++) 124 __CTRACE("%c", 125 curscr->lines[i]->line[j].ch); 126 __CTRACE("\n"); 127 for (j = 0; j < curscr->maxx; j++) 128 __CTRACE("%x", 129 curscr->lines[i]->line[j].attr); 130 __CTRACE("\n"); 131 __CTRACE("W: %d:", i); 132 __CTRACE(" 0x%x \n", win->lines[i]->hash); 133 __CTRACE(" 0x%x ", win->lines[i]->flags); 134 for (j = 0; j < win->maxx; j++) 135 __CTRACE("%c", 136 win->lines[i]->line[j].ch); 137 __CTRACE("\n"); 138 for (j = 0; j < win->maxx; j++) 139 __CTRACE("%x", 140 win->lines[i]->line[j].attr); 141 __CTRACE("\n"); 142 } 143 } 144 #endif /* DEBUG */ 145 146 for (wy = 0; wy < win->maxy; wy++) { 147 #ifdef DEBUG 148 __CTRACE("%d\t%d\t%d\n", 149 wy, *win->lines[wy]->firstchp, *win->lines[wy]->lastchp); 150 #endif 151 if (!curwin) 152 curscr->lines[wy]->hash = win->lines[wy]->hash; 153 if (win->lines[wy]->flags & (__ISDIRTY | __FORCEPAINT)) { 154 if (makech(win, wy) == ERR) 155 return (ERR); 156 else { 157 if (*win->lines[wy]->firstchp >= win->ch_off) 158 *win->lines[wy]->firstchp = win->maxx + 159 win->ch_off; 160 if (*win->lines[wy]->lastchp < win->maxx + 161 win->ch_off) 162 *win->lines[wy]->lastchp = win->ch_off; 163 if (*win->lines[wy]->lastchp < 164 *win->lines[wy]->firstchp) { 165 #ifdef DEBUG 166 __CTRACE("wrefresh: line %d notdirty \n", wy); 167 #endif 168 win->lines[wy]->flags &= ~__ISDIRTY; 169 } 170 } 171 172 } 173 #ifdef DEBUG 174 __CTRACE("\t%d\t%d\n", *win->lines[wy]->firstchp, 175 *win->lines[wy]->lastchp); 176 #endif 177 } 178 179 #ifdef DEBUG 180 __CTRACE("refresh: ly=%d, lx=%d\n", ly, lx); 181 #endif 182 183 if (win == curscr) 184 domvcur(ly, lx, win->cury, win->curx); 185 else { 186 if (win->flags & __LEAVEOK) { 187 curscr->cury = ly; 188 curscr->curx = lx; 189 ly -= win->begy; 190 lx -= win->begx; 191 if (ly >= 0 && ly < win->maxy && lx >= 0 && 192 lx < win->maxx) { 193 win->cury = ly; 194 win->curx = lx; 195 } else 196 win->cury = win->curx = 0; 197 } else { 198 domvcur(ly, lx, win->cury + win->begy, 199 win->curx + win->begx); 200 curscr->cury = win->cury + win->begy; 201 curscr->curx = win->curx + win->begx; 202 } 203 } 204 retval = OK; 205 206 (void)fflush(stdout); 207 return (retval); 208 } 209 210 /* 211 * makech -- 212 * Make a change on the screen. 213 */ 214 static int 215 makech(win, wy) 216 register WINDOW *win; 217 int wy; 218 { 219 static __LDATA blank = {' ', 0}; 220 register int nlsp, clsp; /* Last space in lines. */ 221 register int wx, lch, y; 222 register __LDATA *nsp, *csp, *cp, *cep; 223 u_int force; 224 char *ce; 225 226 /* Is the cursor still on the end of the last line? */ 227 if (wy > 0 && win->lines[wy - 1]->flags & __ISPASTEOL) { 228 domvcur(ly, lx, ly + 1, 0); 229 ly++; 230 lx = 0; 231 } 232 wx = *win->lines[wy]->firstchp - win->ch_off; 233 if (wx < 0) 234 wx = 0; 235 else if (wx >= win->maxx) 236 return (OK); 237 lch = *win->lines[wy]->lastchp - win->ch_off; 238 if (lch < 0) 239 return (OK); 240 else if (lch >= (int) win->maxx) 241 lch = win->maxx - 1; 242 y = wy + win->begy; 243 244 if (curwin) 245 csp = ␣ 246 else 247 csp = &curscr->lines[wy + win->begy]->line[wx + win->begx]; 248 249 nsp = &win->lines[wy]->line[wx]; 250 force = win->lines[wy]->flags & __FORCEPAINT; 251 win->lines[wy]->flags &= ~__FORCEPAINT; 252 if (CE && !curwin) { 253 for (cp = &win->lines[wy]->line[win->maxx - 1]; 254 cp->ch == ' ' && cp->attr == 0; cp--) 255 if (cp <= win->lines[wy]->line) 256 break; 257 nlsp = cp - win->lines[wy]->line; 258 } 259 if (!curwin) 260 ce = CE; 261 else 262 ce = NULL; 263 264 if (force) { 265 if (CM) 266 tputs(tgoto(CM, lx, ly), 0, __cputchar); 267 else { 268 tputs(HO, 0, __cputchar); 269 __mvcur(0, 0, ly, lx, 1); 270 } 271 } 272 while (wx <= lch) { 273 if (!force && memcmp(nsp, csp, sizeof(__LDATA)) == 0) { 274 if (wx <= lch) { 275 while (wx <= lch && 276 memcmp(nsp, csp, sizeof(__LDATA)) == 0) { 277 nsp++; 278 if (!curwin) 279 csp++; 280 ++wx; 281 } 282 continue; 283 } 284 break; 285 } 286 domvcur(ly, lx, y, wx + win->begx); 287 288 #ifdef DEBUG 289 __CTRACE("makech: 1: wx = %d, ly= %d, lx = %d, newy = %d, newx = %d, force =%d\n", 290 wx, ly, lx, y, wx + win->begx, force); 291 #endif 292 ly = y; 293 lx = wx + win->begx; 294 while ((force || memcmp(nsp, csp, sizeof(__LDATA)) != 0) 295 && wx <= lch) { 296 297 if (ce != NULL && win->maxx + win->begx == 298 curscr->maxx && wx >= nlsp && nsp->ch == ' ') { 299 /* Check for clear to end-of-line. */ 300 cep = &curscr->lines[wy]->line[win->maxx - 1]; 301 while (cep->ch == ' ' && cep->attr == 0) 302 if (cep-- <= csp) 303 break; 304 clsp = cep - curscr->lines[wy]->line - 305 win->begx * __LDATASIZE; 306 #ifdef DEBUG 307 __CTRACE("makech: clsp = %d, nlsp = %d\n", clsp, nlsp); 308 #endif 309 if ((clsp - nlsp >= strlen(CE) 310 && clsp < win->maxx * __LDATASIZE) || 311 wy == win->maxy - 1) { 312 #ifdef DEBUG 313 __CTRACE("makech: using CE\n"); 314 #endif 315 tputs(CE, 0, __cputchar); 316 lx = wx + win->begx; 317 while (wx++ <= clsp) { 318 csp->ch = ' '; 319 csp->attr = 0; 320 csp++; 321 } 322 return (OK); 323 } 324 ce = NULL; 325 } 326 327 /* Enter/exit standout mode as appropriate. */ 328 if (SO && (nsp->attr & __STANDOUT) != 329 (curscr->flags & __WSTANDOUT)) { 330 if (nsp->attr & __STANDOUT) { 331 tputs(SO, 0, __cputchar); 332 curscr->flags |= __WSTANDOUT; 333 } else { 334 tputs(SE, 0, __cputchar); 335 curscr->flags &= ~__WSTANDOUT; 336 } 337 } 338 339 wx++; 340 if (wx >= win->maxx && wy == win->maxy - 1 && !curwin) 341 if (win->flags & __SCROLLOK) { 342 if (curscr->flags & __WSTANDOUT 343 && win->flags & __ENDLINE) 344 if (!MS) { 345 tputs(SE, 0, 346 __cputchar); 347 curscr->flags &= 348 ~__WSTANDOUT; 349 } 350 if (!(win->flags & __SCROLLWIN)) { 351 if (!curwin) { 352 csp->attr = nsp->attr; 353 putchar(csp->ch = nsp->ch); 354 } else 355 putchar(nsp->ch); 356 } 357 if (wx + win->begx < curscr->maxx) { 358 domvcur(ly, wx + win->begx, 359 win->begy + win->maxy - 1, 360 win->begx + win->maxx - 1); 361 } 362 ly = win->begy + win->maxy - 1; 363 lx = win->begx + win->maxx - 1; 364 return (OK); 365 } 366 if (wx < win->maxx || wy < win->maxy - 1 || 367 !(win->flags & __SCROLLWIN)) { 368 if (!curwin) { 369 csp->attr = nsp->attr; 370 putchar(csp->ch = nsp->ch); 371 csp++; 372 } else 373 putchar(nsp->ch); 374 } 375 #ifdef DEBUG 376 __CTRACE("makech: putchar(%c)\n", nsp->ch & 0177); 377 #endif 378 if (UC && (nsp->attr & __STANDOUT)) { 379 putchar('\b'); 380 tputs(UC, 0, __cputchar); 381 } 382 nsp++; 383 #ifdef DEBUG 384 __CTRACE("makech: 2: wx = %d, lx = %d\n", wx, lx); 385 #endif 386 } 387 if (lx == wx + win->begx) /* If no change. */ 388 break; 389 lx = wx + win->begx; 390 if (lx >= COLS && AM) 391 lx = COLS - 1; 392 else if (wx >= win->maxx) { 393 domvcur(ly, lx, ly, win->maxx + win->begx - 1); 394 lx = win->maxx + win->begx - 1; 395 } 396 397 #ifdef DEBUG 398 __CTRACE("makech: 3: wx = %d, lx = %d\n", wx, lx); 399 #endif 400 } 401 return (OK); 402 } 403 404 /* 405 * domvcur -- 406 * Do a mvcur, leaving standout mode if necessary. 407 */ 408 static void 409 domvcur(oy, ox, ny, nx) 410 int oy, ox, ny, nx; 411 { 412 if (curscr->flags & __WSTANDOUT && !MS) { 413 tputs(SE, 0, __cputchar); 414 curscr->flags &= ~__WSTANDOUT; 415 } 416 417 __mvcur(oy, ox, ny, nx, 1); 418 } 419 420 /* 421 * Quickch() attempts to detect a pattern in the change of the window 422 * in order to optimize the change, e.g., scroll n lines as opposed to 423 * repainting the screen line by line. 424 */ 425 426 static void 427 quickch(win) 428 WINDOW *win; 429 { 430 #define THRESH (int) win->maxy / 4 431 432 register __LINE *clp, *tmp1, *tmp2; 433 register int bsize, curs, curw, starts, startw, i, j; 434 int n, target, cur_period, bot, top, sc_region; 435 __LDATA buf[1024]; 436 u_int blank_hash; 437 438 /* 439 * Find how many lines from the top of the screen are unchanged. 440 */ 441 for (top = 0; top < win->maxy; top++) 442 if (win->lines[top]->flags & __FORCEPAINT || 443 win->lines[top]->hash != curscr->lines[top]->hash 444 || memcmp(win->lines[top]->line, 445 curscr->lines[top]->line, 446 win->maxx * __LDATASIZE) != 0) 447 break; 448 else 449 win->lines[top]->flags &= ~__ISDIRTY; 450 /* 451 * Find how many lines from bottom of screen are unchanged. 452 */ 453 for (bot = win->maxy - 1; bot >= 0; bot--) 454 if (win->lines[bot]->flags & __FORCEPAINT || 455 win->lines[bot]->hash != curscr->lines[bot]->hash 456 || memcmp(win->lines[bot]->line, 457 curscr->lines[bot]->line, 458 win->maxx * __LDATASIZE) != 0) 459 break; 460 else 461 win->lines[bot]->flags &= ~__ISDIRTY; 462 463 #ifdef NO_JERKINESS 464 /* 465 * If we have a bottom unchanged region return. Scrolling the 466 * bottom region up and then back down causes a screen jitter. 467 * This will increase the number of characters sent to the screen 468 * but it looks better. 469 */ 470 if (bot < win->maxy - 1) 471 return; 472 #endif /* NO_JERKINESS */ 473 474 /* 475 * Search for the largest block of text not changed. 476 * Invariants of the loop: 477 * - Startw is the index of the beginning of the examined block in win. 478 * - Starts is the index of the beginning of the examined block in 479 * curscr. 480 * - Curs is the index of one past the end of the exmined block in win. 481 * - Curw is the index of one past the end of the exmined block in 482 * curscr. 483 * - bsize is the current size of the examined block. 484 */ 485 for (bsize = bot - top; bsize >= THRESH; bsize--) { 486 for (startw = top; startw <= bot - bsize; startw++) 487 for (starts = top; starts <= bot - bsize; 488 starts++) { 489 for (curw = startw, curs = starts; 490 curs < starts + bsize; curw++, curs++) 491 if (win->lines[curw]->flags & 492 __FORCEPAINT || 493 (win->lines[curw]->hash != 494 curscr->lines[curs]->hash || 495 memcmp(win->lines[curw]->line, 496 curscr->lines[curs]->line, 497 win->maxx * __LDATASIZE) != 0)) 498 break; 499 if (curs == starts + bsize) 500 goto done; 501 } 502 } 503 done: 504 /* Did not find anything */ 505 if (bsize < THRESH) 506 return; 507 508 #ifdef DEBUG 509 __CTRACE("quickch:bsize=%d,starts=%d,startw=%d,curw=%d,curs=%d,top=%d,bot=%d\n", 510 bsize, starts, startw, curw, curs, top, bot); 511 #endif 512 513 /* 514 * Make sure that there is no overlap between the bottom and top 515 * regions and the middle scrolled block. 516 */ 517 if (bot < curs) 518 bot = curs - 1; 519 if (top > starts) 520 top = starts; 521 522 n = startw - starts; 523 524 #ifdef DEBUG 525 __CTRACE("#####################################\n"); 526 for (i = 0; i < curscr->maxy; i++) { 527 __CTRACE("C: %d:", i); 528 __CTRACE(" 0x%x \n", curscr->lines[i]->hash); 529 for (j = 0; j < curscr->maxx; j++) 530 __CTRACE("%c", 531 curscr->lines[i]->line[j].ch); 532 __CTRACE("\n"); 533 for (j = 0; j < curscr->maxx; j++) 534 __CTRACE("%x", 535 curscr->lines[i]->line[j].attr); 536 __CTRACE("\n"); 537 __CTRACE("W: %d:", i); 538 __CTRACE(" 0x%x \n", win->lines[i]->hash); 539 __CTRACE(" 0x%x ", win->lines[i]->flags); 540 for (j = 0; j < win->maxx; j++) 541 __CTRACE("%c", 542 win->lines[i]->line[j].ch); 543 __CTRACE("\n"); 544 for (j = 0; j < win->maxx; j++) 545 __CTRACE("%x", 546 win->lines[i]->line[j].attr); 547 __CTRACE("\n"); 548 } 549 #endif 550 551 /* So we don't have to call __hash() each time */ 552 for (i = 0; i < win->maxx; i++) { 553 buf[i].ch = ' '; 554 buf[i].attr = 0; 555 } 556 blank_hash = __hash((char *) buf, win->maxx * __LDATASIZE); 557 558 /* 559 * Perform the rotation to maintain the consistency of curscr. 560 * This is hairy since we are doing an *in place* rotation. 561 * Invariants of the loop: 562 * - I is the index of the current line. 563 * - Target is the index of the target of line i. 564 * - Tmp1 points to current line (i). 565 * - Tmp2 and points to target line (target); 566 * - Cur_period is the index of the end of the current period. 567 * (see below). 568 * 569 * There are 2 major issues here that make this rotation non-trivial: 570 * 1. Scrolling in a scrolling region bounded by the top 571 * and bottom regions determined (whose size is sc_region). 572 * 2. As a result of the use of the mod function, there may be a 573 * period introduced, i.e., 2 maps to 4, 4 to 6, n-2 to 0, and 574 * 0 to 2, which then causes all odd lines not to be rotated. 575 * To remedy this, an index of the end ( = beginning) of the 576 * current 'period' is kept, cur_period, and when it is reached, 577 * the next period is started from cur_period + 1 which is 578 * guaranteed not to have been reached since that would mean that 579 * all records would have been reached. (think about it...). 580 * 581 * Lines in the rotation can have 3 attributes which are marked on the 582 * line so that curscr is consistent with the visual screen. 583 * 1. Not dirty -- lines inside the scrolled block, top region or 584 * bottom region. 585 * 2. Blank lines -- lines in the differential of the scrolling 586 * region adjacent to top and bot regions 587 * depending on scrolling direction. 588 * 3. Dirty line -- all other lines are marked dirty. 589 */ 590 sc_region = bot - top + 1; 591 i = top; 592 tmp1 = curscr->lines[top]; 593 cur_period = top; 594 for (j = top; j <= bot; j++) { 595 target = (i - top + n + sc_region) % sc_region + top; 596 tmp2 = curscr->lines[target]; 597 curscr->lines[target] = tmp1; 598 /* Mark block as clean and blank out scrolled lines. */ 599 clp = curscr->lines[target]; 600 #ifdef DEBUG 601 __CTRACE("quickch: n=%d startw=%d curw=%d i = %d target=%d ", 602 n, startw, curw, i, target); 603 #endif 604 if ((target >= startw && target < curw) || target < top 605 || target > bot) { 606 #ifdef DEBUG 607 __CTRACE("-- notdirty"); 608 #endif 609 win->lines[target]->flags &= ~__ISDIRTY; 610 } else if ((n > 0 && target >= top && target < top + n) || 611 (n < 0 && target <= bot && target > bot + n)) { 612 if (clp->hash != blank_hash || memcmp(clp->line, 613 buf, win->maxx * __LDATASIZE) !=0) { 614 (void)memcpy(clp->line, buf, 615 win->maxx * __LDATASIZE); 616 #ifdef DEBUG 617 __CTRACE("-- blanked out: dirty"); 618 #endif 619 clp->hash = blank_hash; 620 __touchline(win, target, 0, win->maxx - 1, 0); 621 } else { 622 __touchline(win, target, 0, win->maxx - 1, 0); 623 #ifdef DEBUG 624 __CTRACE(" -- blank line already: dirty"); 625 #endif 626 } 627 } else { 628 #ifdef DEBUG 629 __CTRACE(" -- dirty"); 630 #endif 631 __touchline(win, target, 0, win->maxx - 1, 0); 632 } 633 #ifdef DEBUG 634 __CTRACE("\n"); 635 #endif 636 if (target == cur_period) { 637 i = target + 1; 638 tmp1 = curscr->lines[i]; 639 cur_period = i; 640 } else { 641 tmp1 = tmp2; 642 i = target; 643 } 644 } 645 #ifdef DEBUG 646 __CTRACE("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$\n"); 647 for (i = 0; i < curscr->maxy; i++) { 648 __CTRACE("C: %d:", i); 649 for (j = 0; j < curscr->maxx; j++) 650 __CTRACE("%c", 651 curscr->lines[i]->line[j].ch); 652 __CTRACE("\n"); 653 __CTRACE("W: %d:", i); 654 for (j = 0; j < win->maxx; j++) 655 __CTRACE("%c", 656 win->lines[i]->line[j].ch); 657 __CTRACE("\n"); 658 } 659 #endif 660 if (n != 0) { 661 WINDOW *wp; 662 scrolln(win, starts, startw, curs, bot, top); 663 /* 664 * Need to repoint any subwindow lines to the rotated 665 * line structured. 666 */ 667 for (wp = win->nextp; wp != win; wp = wp->nextp) 668 __set_subwin(win, wp); 669 } 670 } 671 672 /* 673 * Scrolln performs the scroll by n lines, where n is starts - startw. 674 */ 675 static void 676 scrolln(win, starts, startw, curs, bot, top) 677 WINDOW *win; 678 int starts, startw, curs, bot, top; 679 { 680 int i, oy, ox, n; 681 682 oy = curscr->cury; 683 ox = curscr->curx; 684 n = starts - startw; 685 686 if (n > 0) { 687 __mvcur(oy, ox, top, 0, 1); 688 /* Scroll up the block */ 689 if (DL) 690 tputs(__tscroll(DL, n), 0, __cputchar); 691 else 692 for(i = 0; i < n; i++) 693 tputs(dl, 0, __cputchar); 694 695 /* 696 * Push down the bottom region. 697 */ 698 __mvcur(top, 0, bot - n + 1, 0, 1); 699 if (AL) 700 tputs(__tscroll(AL, n), 0, __cputchar); 701 else 702 for(i = 0; i < n; i++) 703 tputs(al, 0, __cputchar); 704 __mvcur(bot - n + 1, 0, oy, ox, 1); 705 } else { 706 /* Preserve the bottom lines */ 707 __mvcur(oy, ox, bot + n + 1, 0, 1); /* n < 0 */ 708 if (DL) 709 tputs(__tscroll(DL, -n), 0, __cputchar); 710 else 711 for(i = n; i < 0; i++) 712 tputs(dl, 0, __cputchar); 713 __mvcur(bot + n + 1, 0, top, 0, 1); 714 715 /* Scroll the block down */ 716 if (AL) 717 tputs(__tscroll(AL, -n), 0, __cputchar); 718 else 719 for(i = n; i < 0; i++) 720 tputs(al, 0, __cputchar); 721 __mvcur(top, 0, oy, ox, 1); 722 } 723 } 724
Indexes created Sun Sep 21 20:09:37 GMT 2025