| 1 | /* Cursor motion subroutines for GNU Emacs. |
| 2 | Copyright (C) 1985, 1995, 2002, 2003, 2004, |
| 3 | 2005, 2006 Free Software Foundation, Inc. |
| 4 | based primarily on public domain code written by Chris Torek |
| 5 | |
| 6 | This file is part of GNU Emacs. |
| 7 | |
| 8 | GNU Emacs 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 | GNU Emacs 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 GNU Emacs; see the file COPYING. If not, write to |
| 20 | the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| 21 | Boston, MA 02110-1301, USA. */ |
| 22 | |
| 23 | |
| 24 | #include <config.h> |
| 25 | #include <stdio.h> |
| 26 | #include "cm.h" |
| 27 | #include "termhooks.h" |
| 28 | |
| 29 | /* For now, don't try to include termcap.h. On some systems, |
| 30 | configure finds a non-standard termcap.h that the main build |
| 31 | won't find. */ |
| 32 | |
| 33 | #if defined HAVE_TERMCAP_H && 0 |
| 34 | #include <termcap.h> |
| 35 | #else |
| 36 | extern void tputs P_ ((const char *, int, int (*)(int))); |
| 37 | extern char *tgoto P_ ((const char *, int, int)); |
| 38 | #endif |
| 39 | |
| 40 | #define BIG 9999 /* 9999 good on VAXen. For 16 bit machines |
| 41 | use about 2000.... */ |
| 42 | |
| 43 | extern char *BC, *UP; |
| 44 | |
| 45 | int cost; /* sums up costs */ |
| 46 | |
| 47 | /* ARGSUSED */ |
| 48 | int |
| 49 | evalcost (c) |
| 50 | char c; |
| 51 | { |
| 52 | cost++; |
| 53 | return c; |
| 54 | } |
| 55 | |
| 56 | int |
| 57 | cmputc (c) |
| 58 | char c; |
| 59 | { |
| 60 | if (termscript) |
| 61 | fputc (c & 0177, termscript); |
| 62 | putchar (c & 0177); |
| 63 | return c; |
| 64 | } |
| 65 | |
| 66 | /* NEXT TWO ARE DONE WITH MACROS */ |
| 67 | #if 0 |
| 68 | /* |
| 69 | * Assume the cursor is at row row, column col. Normally used only after |
| 70 | * clearing the screen, when the cursor is at (0, 0), but what the heck, |
| 71 | * let's let the guy put it anywhere. |
| 72 | */ |
| 73 | |
| 74 | static |
| 75 | at (row, col) { |
| 76 | curY = row; |
| 77 | curX = col; |
| 78 | } |
| 79 | |
| 80 | /* |
| 81 | * Add n columns to the current cursor position. |
| 82 | */ |
| 83 | |
| 84 | static |
| 85 | addcol (n) { |
| 86 | curX += n; |
| 87 | |
| 88 | /* |
| 89 | * If cursor hit edge of screen, what happened? |
| 90 | * N.B.: DO NOT!! write past edge of screen. If you do, you |
| 91 | * deserve what you get. Furthermore, on terminals with |
| 92 | * autowrap (but not magicwrap), don't write in the last column |
| 93 | * of the last line. |
| 94 | */ |
| 95 | |
| 96 | if (curX == Wcm.cm_cols) { |
| 97 | /* |
| 98 | * Well, if magicwrap, still there, past the edge of the |
| 99 | * screen (!). If autowrap, on the col 0 of the next line. |
| 100 | * Otherwise on last column. |
| 101 | */ |
| 102 | |
| 103 | if (Wcm.cm_magicwrap) |
| 104 | ; /* "limbo" */ |
| 105 | else if (Wcm.cm_autowrap) { |
| 106 | curX = 0; |
| 107 | curY++; /* Beware end of screen! */ |
| 108 | } |
| 109 | else |
| 110 | curX--; |
| 111 | } |
| 112 | } |
| 113 | #endif |
| 114 | |
| 115 | /* |
| 116 | * Terminals with magicwrap (xn) don't all behave identically. |
| 117 | * The VT100 leaves the cursor in the last column but will wrap before |
| 118 | * printing the next character. I hear that the Concept terminal does |
| 119 | * the wrap immediately but ignores the next newline it sees. And some |
| 120 | * terminals just have buggy firmware, and think that the cursor is still |
| 121 | * in limbo if we use direct cursor addressing from the phantom column. |
| 122 | * The only guaranteed safe thing to do is to emit a CRLF immediately |
| 123 | * after we reach the last column; this takes us to a known state. |
| 124 | */ |
| 125 | void |
| 126 | cmcheckmagic () |
| 127 | { |
| 128 | if (curX == FrameCols) |
| 129 | { |
| 130 | if (!MagicWrap || curY >= FrameRows - 1) |
| 131 | abort (); |
| 132 | if (termscript) |
| 133 | putc ('\r', termscript); |
| 134 | putchar ('\r'); |
| 135 | if (termscript) |
| 136 | putc ('\n', termscript); |
| 137 | putchar ('\n'); |
| 138 | curX = 0; |
| 139 | curY++; |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | |
| 144 | /* |
| 145 | * (Re)Initialize the cost factors, given the output speed of the terminal |
| 146 | * in the variable ospeed. (Note: this holds B300, B9600, etc -- ie stuff |
| 147 | * out of <sgtty.h>.) |
| 148 | */ |
| 149 | |
| 150 | void |
| 151 | cmcostinit () |
| 152 | { |
| 153 | char *p; |
| 154 | |
| 155 | #define COST(x,e) (x ? (cost = 0, tputs (x, 1, e), cost) : BIG) |
| 156 | #define CMCOST(x,e) ((x == 0) ? BIG : (p = tgoto(x, 0, 0), COST(p ,e))) |
| 157 | |
| 158 | Wcm.cc_up = COST (Wcm.cm_up, evalcost); |
| 159 | Wcm.cc_down = COST (Wcm.cm_down, evalcost); |
| 160 | Wcm.cc_left = COST (Wcm.cm_left, evalcost); |
| 161 | Wcm.cc_right = COST (Wcm.cm_right, evalcost); |
| 162 | Wcm.cc_home = COST (Wcm.cm_home, evalcost); |
| 163 | Wcm.cc_cr = COST (Wcm.cm_cr, evalcost); |
| 164 | Wcm.cc_ll = COST (Wcm.cm_ll, evalcost); |
| 165 | Wcm.cc_tab = Wcm.cm_tabwidth ? COST (Wcm.cm_tab, evalcost) : BIG; |
| 166 | |
| 167 | /* |
| 168 | * These last three are actually minimum costs. When (if) they are |
| 169 | * candidates for the least-cost motion, the real cost is computed. |
| 170 | * (Note that "0" is the assumed to generate the minimum cost. |
| 171 | * While this is not necessarily true, I have yet to see a terminal |
| 172 | * for which is not; all the terminals that have variable-cost |
| 173 | * cursor motion seem to take straight numeric values. --ACT) |
| 174 | */ |
| 175 | |
| 176 | Wcm.cc_abs = CMCOST (Wcm.cm_abs, evalcost); |
| 177 | Wcm.cc_habs = CMCOST (Wcm.cm_habs, evalcost); |
| 178 | Wcm.cc_vabs = CMCOST (Wcm.cm_vabs, evalcost); |
| 179 | |
| 180 | #undef CMCOST |
| 181 | #undef COST |
| 182 | } |
| 183 | |
| 184 | /* |
| 185 | * Calculate the cost to move from (srcy, srcx) to (dsty, dstx) using |
| 186 | * up and down, and left and right, motions, and tabs. If doit is set |
| 187 | * actually perform the motion. |
| 188 | */ |
| 189 | |
| 190 | static int |
| 191 | calccost (srcy, srcx, dsty, dstx, doit) |
| 192 | int srcy, srcx, dsty, dstx, doit; |
| 193 | { |
| 194 | register int deltay, |
| 195 | deltax, |
| 196 | c, |
| 197 | totalcost; |
| 198 | int ntabs, |
| 199 | n2tabs, |
| 200 | tabx, |
| 201 | tab2x, |
| 202 | tabcost; |
| 203 | register char *p; |
| 204 | |
| 205 | /* If have just wrapped on a terminal with xn, |
| 206 | don't believe the cursor position: give up here |
| 207 | and force use of absolute positioning. */ |
| 208 | |
| 209 | if (curX == Wcm.cm_cols) |
| 210 | goto fail; |
| 211 | |
| 212 | totalcost = 0; |
| 213 | if ((deltay = dsty - srcy) == 0) |
| 214 | goto x; |
| 215 | if (deltay < 0) |
| 216 | p = Wcm.cm_up, c = Wcm.cc_up, deltay = -deltay; |
| 217 | else |
| 218 | p = Wcm.cm_down, c = Wcm.cc_down; |
| 219 | if (c == BIG) { /* caint get thar from here */ |
| 220 | if (doit) |
| 221 | printf ("OOPS"); |
| 222 | return c; |
| 223 | } |
| 224 | totalcost = c * deltay; |
| 225 | if (doit) |
| 226 | while (--deltay >= 0) |
| 227 | tputs (p, 1, cmputc); |
| 228 | x: |
| 229 | if ((deltax = dstx - srcx) == 0) |
| 230 | goto done; |
| 231 | if (deltax < 0) { |
| 232 | p = Wcm.cm_left, c = Wcm.cc_left, deltax = -deltax; |
| 233 | goto dodelta; /* skip all the tab junk */ |
| 234 | } |
| 235 | /* Tabs (the toughie) */ |
| 236 | if (Wcm.cc_tab >= BIG || !Wcm.cm_usetabs) |
| 237 | goto olddelta; /* forget it! */ |
| 238 | |
| 239 | /* |
| 240 | * ntabs is # tabs towards but not past dstx; n2tabs is one more |
| 241 | * (ie past dstx), but this is only valid if that is not past the |
| 242 | * right edge of the screen. We can check that at the same time |
| 243 | * as we figure out where we would be if we use the tabs (which |
| 244 | * we will put into tabx (for ntabs) and tab2x (for n2tabs)). |
| 245 | */ |
| 246 | |
| 247 | ntabs = (deltax + srcx % Wcm.cm_tabwidth) / Wcm.cm_tabwidth; |
| 248 | n2tabs = ntabs + 1; |
| 249 | tabx = (srcx / Wcm.cm_tabwidth + ntabs) * Wcm.cm_tabwidth; |
| 250 | tab2x = tabx + Wcm.cm_tabwidth; |
| 251 | |
| 252 | if (tab2x >= Wcm.cm_cols) /* too far (past edge) */ |
| 253 | n2tabs = 0; |
| 254 | |
| 255 | /* |
| 256 | * Now set tabcost to the cost for using ntabs, and c to the cost |
| 257 | * for using n2tabs, then pick the minimum. |
| 258 | */ |
| 259 | |
| 260 | /* cost for ntabs + cost for right motion */ |
| 261 | tabcost = ntabs ? ntabs * Wcm.cc_tab + (dstx - tabx) * Wcm.cc_right |
| 262 | : BIG; |
| 263 | |
| 264 | /* cost for n2tabs + cost for left motion */ |
| 265 | c = n2tabs ? n2tabs * Wcm.cc_tab + (tab2x - dstx) * Wcm.cc_left |
| 266 | : BIG; |
| 267 | |
| 268 | if (c < tabcost) /* then cheaper to overshoot & back up */ |
| 269 | ntabs = n2tabs, tabcost = c, tabx = tab2x; |
| 270 | |
| 271 | if (tabcost >= BIG) /* caint use tabs */ |
| 272 | goto newdelta; |
| 273 | |
| 274 | /* |
| 275 | * See if tabcost is less than just moving right |
| 276 | */ |
| 277 | |
| 278 | if (tabcost < (deltax * Wcm.cc_right)) { |
| 279 | totalcost += tabcost; /* use the tabs */ |
| 280 | if (doit) |
| 281 | while (--ntabs >= 0) |
| 282 | tputs (Wcm.cm_tab, 1, cmputc); |
| 283 | srcx = tabx; |
| 284 | } |
| 285 | |
| 286 | /* |
| 287 | * Now might as well just recompute the delta. |
| 288 | */ |
| 289 | |
| 290 | newdelta: |
| 291 | if ((deltax = dstx - srcx) == 0) |
| 292 | goto done; |
| 293 | olddelta: |
| 294 | if (deltax > 0) |
| 295 | p = Wcm.cm_right, c = Wcm.cc_right; |
| 296 | else |
| 297 | p = Wcm.cm_left, c = Wcm.cc_left, deltax = -deltax; |
| 298 | |
| 299 | dodelta: |
| 300 | if (c == BIG) { /* caint get thar from here */ |
| 301 | fail: |
| 302 | if (doit) |
| 303 | printf ("OOPS"); |
| 304 | return BIG; |
| 305 | } |
| 306 | totalcost += c * deltax; |
| 307 | if (doit) |
| 308 | while (--deltax >= 0) |
| 309 | tputs (p, 1, cmputc); |
| 310 | done: |
| 311 | return totalcost; |
| 312 | } |
| 313 | |
| 314 | #if 0 |
| 315 | losecursor () |
| 316 | { |
| 317 | curY = -1; |
| 318 | } |
| 319 | #endif |
| 320 | |
| 321 | #define USEREL 0 |
| 322 | #define USEHOME 1 |
| 323 | #define USELL 2 |
| 324 | #define USECR 3 |
| 325 | |
| 326 | void |
| 327 | cmgoto (row, col) |
| 328 | int row, col; |
| 329 | { |
| 330 | int homecost, |
| 331 | crcost, |
| 332 | llcost, |
| 333 | relcost, |
| 334 | directcost; |
| 335 | int use; |
| 336 | char *p, |
| 337 | *dcm; |
| 338 | |
| 339 | /* First the degenerate case */ |
| 340 | if (row == curY && col == curX) /* already there */ |
| 341 | return; |
| 342 | |
| 343 | if (curY >= 0 && curX >= 0) |
| 344 | { |
| 345 | /* We may have quick ways to go to the upper-left, bottom-left, |
| 346 | * start-of-line, or start-of-next-line. Or it might be best to |
| 347 | * start where we are. Examine the options, and pick the cheapest. |
| 348 | */ |
| 349 | |
| 350 | relcost = calccost (curY, curX, row, col, 0); |
| 351 | use = USEREL; |
| 352 | if ((homecost = Wcm.cc_home) < BIG) |
| 353 | homecost += calccost (0, 0, row, col, 0); |
| 354 | if (homecost < relcost) |
| 355 | relcost = homecost, use = USEHOME; |
| 356 | if ((llcost = Wcm.cc_ll) < BIG) |
| 357 | llcost += calccost (Wcm.cm_rows - 1, 0, row, col, 0); |
| 358 | if (llcost < relcost) |
| 359 | relcost = llcost, use = USELL; |
| 360 | if ((crcost = Wcm.cc_cr) < BIG) { |
| 361 | if (Wcm.cm_autolf) |
| 362 | if (curY + 1 >= Wcm.cm_rows) |
| 363 | crcost = BIG; |
| 364 | else |
| 365 | crcost += calccost (curY + 1, 0, row, col, 0); |
| 366 | else |
| 367 | crcost += calccost (curY, 0, row, col, 0); |
| 368 | } |
| 369 | if (crcost < relcost) |
| 370 | relcost = crcost, use = USECR; |
| 371 | directcost = Wcm.cc_abs, dcm = Wcm.cm_abs; |
| 372 | if (row == curY && Wcm.cc_habs < BIG) |
| 373 | directcost = Wcm.cc_habs, dcm = Wcm.cm_habs; |
| 374 | else if (col == curX && Wcm.cc_vabs < BIG) |
| 375 | directcost = Wcm.cc_vabs, dcm = Wcm.cm_vabs; |
| 376 | } |
| 377 | else |
| 378 | { |
| 379 | directcost = 0, relcost = 100000; |
| 380 | dcm = Wcm.cm_abs; |
| 381 | } |
| 382 | |
| 383 | /* |
| 384 | * In the following comparison, the = in <= is because when the costs |
| 385 | * are the same, it looks nicer (I think) to move directly there. |
| 386 | */ |
| 387 | if (directcost <= relcost) |
| 388 | { |
| 389 | /* compute REAL direct cost */ |
| 390 | cost = 0; |
| 391 | p = dcm == Wcm.cm_habs ? tgoto (dcm, row, col) : |
| 392 | tgoto (dcm, col, row); |
| 393 | tputs (p, 1, evalcost); |
| 394 | if (cost <= relcost) |
| 395 | { /* really is cheaper */ |
| 396 | tputs (p, 1, cmputc); |
| 397 | curY = row, curX = col; |
| 398 | return; |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | switch (use) |
| 403 | { |
| 404 | case USEHOME: |
| 405 | tputs (Wcm.cm_home, 1, cmputc); |
| 406 | curY = 0, curX = 0; |
| 407 | break; |
| 408 | |
| 409 | case USELL: |
| 410 | tputs (Wcm.cm_ll, 1, cmputc); |
| 411 | curY = Wcm.cm_rows - 1, curX = 0; |
| 412 | break; |
| 413 | |
| 414 | case USECR: |
| 415 | tputs (Wcm.cm_cr, 1, cmputc); |
| 416 | if (Wcm.cm_autolf) |
| 417 | curY++; |
| 418 | curX = 0; |
| 419 | break; |
| 420 | } |
| 421 | |
| 422 | (void) calccost (curY, curX, row, col, 1); |
| 423 | curY = row, curX = col; |
| 424 | } |
| 425 | |
| 426 | /* Clear out all terminal info. |
| 427 | Used before copying into it the info on the actual terminal. |
| 428 | */ |
| 429 | |
| 430 | void |
| 431 | Wcm_clear () |
| 432 | { |
| 433 | bzero (&Wcm, sizeof Wcm); |
| 434 | UP = 0; |
| 435 | BC = 0; |
| 436 | } |
| 437 | |
| 438 | /* |
| 439 | * Initialized stuff |
| 440 | * Return 0 if can do CM. |
| 441 | * Return -1 if cannot. |
| 442 | * Return -2 if size not specified. |
| 443 | */ |
| 444 | |
| 445 | int |
| 446 | Wcm_init () |
| 447 | { |
| 448 | #if 0 |
| 449 | if (Wcm.cm_abs && !Wcm.cm_ds) |
| 450 | return 0; |
| 451 | #endif |
| 452 | if (Wcm.cm_abs) |
| 453 | return 0; |
| 454 | /* Require up and left, and, if no absolute, down and right */ |
| 455 | if (!Wcm.cm_up || !Wcm.cm_left) |
| 456 | return - 1; |
| 457 | if (!Wcm.cm_abs && (!Wcm.cm_down || !Wcm.cm_right)) |
| 458 | return - 1; |
| 459 | /* Check that we know the size of the screen.... */ |
| 460 | if (Wcm.cm_rows <= 0 || Wcm.cm_cols <= 0) |
| 461 | return - 2; |
| 462 | return 0; |
| 463 | } |
| 464 | |
| 465 | /* arch-tag: bcf64c02-00f6-44ef-94b6-c56eab5b3dc4 |
| 466 | (do not change this comment) */ |