Skip to content
This repository
tag: libc-970324
Fetching contributors…

Octocat-spinner-32-eaf2f5

Cannot retrieve contributors at this time

file 446 lines (384 sloc) 11.123 kb
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445
/* Cursor motion subroutines for GNU Emacs.
Copyright (C) 1985, 1995 Free Software Foundation, Inc.
based primarily on public domain code written by Chris Torek

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */


#include <config.h>
#include <stdio.h>
#include "cm.h"
#include "termhooks.h"

#define BIG 9999 /* 9999 good on VAXen. For 16 bit machines
use about 2000.... */

char *tgoto ();

extern char *BC, *UP;

int cost; /* sums up costs */

/* ARGSUSED */
evalcost (c)
     char c;
{
  cost++;
  return c;
}

cmputc (c)
     char c;
{
  if (termscript)
    fputc (c & 0177, termscript);
  putchar (c & 0177);
  return c;
}

/* NEXT TWO ARE DONE WITH MACROS */
#if 0
/*
* Assume the cursor is at row row, column col. Normally used only after
* clearing the screen, when the cursor is at (0, 0), but what the heck,
* let's let the guy put it anywhere.
*/

static
at (row, col) {
curY = row;
curX = col;
}

/*
* Add n columns to the current cursor position.
*/

static
addcol (n) {
curX += n;

/*
* If cursor hit edge of screen, what happened?
* N.B.: DO NOT!! write past edge of screen. If you do, you
* deserve what you get. Furthermore, on terminals with
* autowrap (but not magicwrap), don't write in the last column
* of the last line.
*/

if (curX == Wcm.cm_cols) {
/*
* Well, if magicwrap, still there, past the edge of the
* screen (!). If autowrap, on the col 0 of the next line.
* Otherwise on last column.
*/

if (Wcm.cm_magicwrap)
; /* "limbo" */
else if (Wcm.cm_autowrap) {
curX = 0;
curY++; /* Beware end of screen! */
}
else
curX--;
}
}
#endif

/*
* Terminals with magicwrap (xn) don't all behave identically.
* The VT100 leaves the cursor in the last column but will wrap before
* printing the next character. I hear that the Concept terminal does
* the wrap immediately but ignores the next newline it sees. And some
* terminals just have buggy firmware, and think that the cursor is still
* in limbo if we use direct cursor addressing from the phantom column.
* The only guaranteed safe thing to do is to emit a CRLF immediately
* after we reach the last column; this takes us to a known state.
*/
void
cmcheckmagic ()
{
  if (curX == FrameCols)
    {
      if (!MagicWrap || curY >= FrameRows - 1)
abort ();
      if (termscript)
putc ('\r', termscript);
      putchar ('\r');
      if (termscript)
putc ('\n', termscript);
      putchar ('\n');
      curX = 0;
      curY++;
    }
}


/*
* (Re)Initialize the cost factors, given the output speed of the terminal
* in the variable ospeed. (Note: this holds B300, B9600, etc -- ie stuff
* out of <sgtty.h>.)
*/

cmcostinit ()
{
    char *p;

#define COST(x,e) (x ? (cost = 0, tputs (x, 1, e), cost) : BIG)
#define CMCOST(x,e) ((x == 0) ? BIG : (p = tgoto(x, 0, 0), COST(p ,e)))

    Wcm.cc_up = COST (Wcm.cm_up, evalcost);
    Wcm.cc_down = COST (Wcm.cm_down, evalcost);
    Wcm.cc_left = COST (Wcm.cm_left, evalcost);
    Wcm.cc_right = COST (Wcm.cm_right, evalcost);
    Wcm.cc_home = COST (Wcm.cm_home, evalcost);
    Wcm.cc_cr = COST (Wcm.cm_cr, evalcost);
    Wcm.cc_ll = COST (Wcm.cm_ll, evalcost);
    Wcm.cc_tab = Wcm.cm_tabwidth ? COST (Wcm.cm_tab, evalcost) : BIG;

    /*
* These last three are actually minimum costs. When (if) they are
* candidates for the least-cost motion, the real cost is computed.
* (Note that "0" is the assumed to generate the minimum cost.
* While this is not necessarily true, I have yet to see a terminal
* for which is not; all the terminals that have variable-cost
* cursor motion seem to take straight numeric values. --ACT)
*/

    Wcm.cc_abs = CMCOST (Wcm.cm_abs, evalcost);
    Wcm.cc_habs = CMCOST (Wcm.cm_habs, evalcost);
    Wcm.cc_vabs = CMCOST (Wcm.cm_vabs, evalcost);

#undef CMCOST
#undef COST
}

/*
* Calculate the cost to move from (srcy, srcx) to (dsty, dstx) using
* up and down, and left and right, motions, and tabs. If doit is set
* actually perform the motion.
*/

static
calccost (srcy, srcx, dsty, dstx, doit)
{
    register int deltay,
                    deltax,
                    c,
                    totalcost;
    int ntabs,
            n2tabs,
            tabx,
            tab2x,
            tabcost;
    register char *p;

    /* If have just wrapped on a terminal with xn,
don't believe the cursor position: give up here
and force use of absolute positioning. */

    if (curX == Wcm.cm_cols)
      goto fail;

    totalcost = 0;
    if ((deltay = dsty - srcy) == 0)
goto x;
    if (deltay < 0)
p = Wcm.cm_up, c = Wcm.cc_up, deltay = -deltay;
    else
p = Wcm.cm_down, c = Wcm.cc_down;
    if (c == BIG) { /* caint get thar from here */
if (doit)
printf ("OOPS");
return c;
    }
    totalcost = c * deltay;
    if (doit)
while (--deltay >= 0)
tputs (p, 1, cmputc);
x:
    if ((deltax = dstx - srcx) == 0)
goto done;
    if (deltax < 0) {
p = Wcm.cm_left, c = Wcm.cc_left, deltax = -deltax;
goto dodelta; /* skip all the tab junk */
    }
    /* Tabs (the toughie) */
    if (Wcm.cc_tab >= BIG || !Wcm.cm_usetabs)
goto olddelta; /* forget it! */

    /*
* ntabs is # tabs towards but not past dstx; n2tabs is one more
* (ie past dstx), but this is only valid if that is not past the
* right edge of the screen. We can check that at the same time
* as we figure out where we would be if we use the tabs (which
* we will put into tabx (for ntabs) and tab2x (for n2tabs)).
*/

    ntabs = (deltax + srcx % Wcm.cm_tabwidth) / Wcm.cm_tabwidth;
    n2tabs = ntabs + 1;
    tabx = (srcx / Wcm.cm_tabwidth + ntabs) * Wcm.cm_tabwidth;
    tab2x = tabx + Wcm.cm_tabwidth;

    if (tab2x >= Wcm.cm_cols) /* too far (past edge) */
n2tabs = 0;

    /*
* Now set tabcost to the cost for using ntabs, and c to the cost
* for using n2tabs, then pick the minimum.
*/

/* cost for ntabs + cost for right motion */
    tabcost = ntabs ? ntabs * Wcm.cc_tab + (dstx - tabx) * Wcm.cc_right
: BIG;

/* cost for n2tabs + cost for left motion */
    c = n2tabs ? n2tabs * Wcm.cc_tab + (tab2x - dstx) * Wcm.cc_left
: BIG;

    if (c < tabcost) /* then cheaper to overshoot & back up */
ntabs = n2tabs, tabcost = c, tabx = tab2x;

    if (tabcost >= BIG) /* caint use tabs */
goto newdelta;

    /*
* See if tabcost is less than just moving right
*/

    if (tabcost < (deltax * Wcm.cc_right)) {
totalcost += tabcost; /* use the tabs */
if (doit)
while (--ntabs >= 0)
tputs (Wcm.cm_tab, 1, cmputc);
srcx = tabx;
    }

    /*
* Now might as well just recompute the delta.
*/

newdelta:
    if ((deltax = dstx - srcx) == 0)
goto done;
olddelta:
    if (deltax > 0)
p = Wcm.cm_right, c = Wcm.cc_right;
    else
p = Wcm.cm_left, c = Wcm.cc_left, deltax = -deltax;

dodelta:
    if (c == BIG) { /* caint get thar from here */
fail:
if (doit)
printf ("OOPS");
return BIG;
    }
    totalcost += c * deltax;
    if (doit)
while (--deltax >= 0)
tputs (p, 1, cmputc);
done:
    return totalcost;
}

#if 0
losecursor ()
{
  curY = -1;
}
#endif

#define USEREL 0
#define USEHOME 1
#define USELL 2
#define USECR 3

cmgoto (row, col)
{
    int homecost,
            crcost,
            llcost,
            relcost,
            directcost;
    int use;
    char *p,
           *dcm;

  /* First the degenerate case */
  if (row == curY && col == curX) /* already there */
    return;

  if (curY >= 0 && curX >= 0)
    {
      /* We may have quick ways to go to the upper-left, bottom-left,
* start-of-line, or start-of-next-line. Or it might be best to
* start where we are. Examine the options, and pick the cheapest.
*/

      relcost = calccost (curY, curX, row, col, 0);
      use = USEREL;
      if ((homecost = Wcm.cc_home) < BIG)
homecost += calccost (0, 0, row, col, 0);
      if (homecost < relcost)
relcost = homecost, use = USEHOME;
      if ((llcost = Wcm.cc_ll) < BIG)
llcost += calccost (Wcm.cm_rows - 1, 0, row, col, 0);
      if (llcost < relcost)
relcost = llcost, use = USELL;
      if ((crcost = Wcm.cc_cr) < BIG) {
if (Wcm.cm_autolf)
if (curY + 1 >= Wcm.cm_rows)
crcost = BIG;
else
crcost += calccost (curY + 1, 0, row, col, 0);
else
crcost += calccost (curY, 0, row, col, 0);
      }
      if (crcost < relcost)
relcost = crcost, use = USECR;
      directcost = Wcm.cc_abs, dcm = Wcm.cm_abs;
      if (row == curY && Wcm.cc_habs < BIG)
directcost = Wcm.cc_habs, dcm = Wcm.cm_habs;
      else if (col == curX && Wcm.cc_vabs < BIG)
directcost = Wcm.cc_vabs, dcm = Wcm.cm_vabs;
    }
  else
    {
      directcost = 0, relcost = 100000;
      dcm = Wcm.cm_abs;
    }

  /*
* In the following comparison, the = in <= is because when the costs
* are the same, it looks nicer (I think) to move directly there.
*/
  if (directcost <= relcost)
    {
      /* compute REAL direct cost */
      cost = 0;
      p = dcm == Wcm.cm_habs ? tgoto (dcm, row, col) :
tgoto (dcm, col, row);
      tputs (p, 1, evalcost);
      if (cost <= relcost)
{ /* really is cheaper */
tputs (p, 1, cmputc);
curY = row, curX = col;
return;
}
    }

  switch (use)
    {
    case USEHOME:
      tputs (Wcm.cm_home, 1, cmputc);
      curY = 0, curX = 0;
      break;

    case USELL:
      tputs (Wcm.cm_ll, 1, cmputc);
      curY = Wcm.cm_rows - 1, curX = 0;
      break;

    case USECR:
      tputs (Wcm.cm_cr, 1, cmputc);
      if (Wcm.cm_autolf)
curY++;
      curX = 0;
      break;
    }

  (void) calccost (curY, curX, row, col, 1);
  curY = row, curX = col;
}

/* Clear out all terminal info.
Used before copying into it the info on the actual terminal.
*/

Wcm_clear ()
{
  bzero (&Wcm, sizeof Wcm);
  UP = 0;
  BC = 0;
}

/*
* Initialized stuff
* Return 0 if can do CM.
* Return -1 if cannot.
* Return -2 if size not specified.
*/

Wcm_init ()
{
#if 0
if (Wcm.cm_abs && !Wcm.cm_ds)
return 0;
#endif
  if (Wcm.cm_abs)
    return 0;
  /* Require up and left, and, if no absolute, down and right */
  if (!Wcm.cm_up || !Wcm.cm_left)
    return - 1;
  if (!Wcm.cm_abs && (!Wcm.cm_down || !Wcm.cm_right))
    return - 1;
  /* Check that we know the size of the screen.... */
  if (Wcm.cm_rows <= 0 || Wcm.cm_cols <= 0)
    return - 2;
  return 0;
}
Something went wrong with that request. Please try again.