Commit | Line | Data |
---|---|---|
d427b66a | 1 | /* Cursor motion subroutines for GNU Emacs. |
f8c25f1b | 2 | Copyright (C) 1985, 1995 Free Software Foundation, Inc. |
d427b66a JB |
3 | based primarily on public domain code written by Chris Torek |
4 | ||
5 | This file is part of GNU Emacs. | |
6 | ||
7 | GNU Emacs is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
4fc440b7 | 9 | the Free Software Foundation; either version 2, or (at your option) |
d427b66a JB |
10 | any later version. |
11 | ||
12 | GNU Emacs is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GNU Emacs; see the file COPYING. If not, write to | |
3b7ad313 EN |
19 | the Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
20 | Boston, MA 02111-1307, USA. */ | |
d427b66a JB |
21 | |
22 | ||
18160b98 | 23 | #include <config.h> |
d427b66a JB |
24 | #include <stdio.h> |
25 | #include "cm.h" | |
26 | #include "termhooks.h" | |
27 | ||
28 | #define BIG 9999 /* 9999 good on VAXen. For 16 bit machines | |
29 | use about 2000.... */ | |
30 | ||
31 | char *tgoto (); | |
32 | ||
33 | extern char *BC, *UP; | |
34 | ||
35 | int cost; /* sums up costs */ | |
36 | ||
37 | /* ARGSUSED */ | |
38 | evalcost (c) | |
39 | char c; | |
40 | { | |
41 | cost++; | |
97f11a9d | 42 | return c; |
d427b66a JB |
43 | } |
44 | ||
d427b66a JB |
45 | cmputc (c) |
46 | char c; | |
47 | { | |
48 | if (termscript) | |
49 | fputc (c & 0177, termscript); | |
50 | putchar (c & 0177); | |
97f11a9d | 51 | return c; |
d427b66a JB |
52 | } |
53 | ||
54 | /* NEXT TWO ARE DONE WITH MACROS */ | |
55 | #if 0 | |
56 | /* | |
57 | * Assume the cursor is at row row, column col. Normally used only after | |
58 | * clearing the screen, when the cursor is at (0, 0), but what the heck, | |
59 | * let's let the guy put it anywhere. | |
60 | */ | |
61 | ||
62 | static | |
63 | at (row, col) { | |
64 | curY = row; | |
65 | curX = col; | |
66 | } | |
67 | ||
68 | /* | |
69 | * Add n columns to the current cursor position. | |
70 | */ | |
71 | ||
72 | static | |
73 | addcol (n) { | |
74 | curX += n; | |
75 | ||
76 | /* | |
77 | * If cursor hit edge of screen, what happened? | |
78 | * N.B.: DO NOT!! write past edge of screen. If you do, you | |
79 | * deserve what you get. Furthermore, on terminals with | |
80 | * autowrap (but not magicwrap), don't write in the last column | |
81 | * of the last line. | |
82 | */ | |
83 | ||
84 | if (curX == Wcm.cm_cols) { | |
85 | /* | |
86 | * Well, if magicwrap, still there, past the edge of the | |
87 | * screen (!). If autowrap, on the col 0 of the next line. | |
88 | * Otherwise on last column. | |
89 | */ | |
90 | ||
91 | if (Wcm.cm_magicwrap) | |
92 | ; /* "limbo" */ | |
93 | else if (Wcm.cm_autowrap) { | |
94 | curX = 0; | |
95 | curY++; /* Beware end of screen! */ | |
96 | } | |
97 | else | |
98 | curX--; | |
99 | } | |
100 | } | |
101 | #endif | |
102 | ||
902a3b86 KH |
103 | /* |
104 | * Terminals with magicwrap (xn) don't all behave identically. | |
105 | * The VT100 leaves the cursor in the last column but will wrap before | |
106 | * printing the next character. I hear that the Concept terminal does | |
107 | * the wrap immediately but ignores the next newline it sees. And some | |
108 | * terminals just have buggy firmware, and think that the cursor is still | |
109 | * in limbo if we use direct cursor addressing from the phantom column. | |
110 | * The only guaranteed safe thing to do is to emit a CRLF immediately | |
111 | * after we reach the last column; this takes us to a known state. | |
112 | */ | |
113 | void | |
114 | cmcheckmagic () | |
115 | { | |
116 | if (curX == FrameCols) | |
117 | { | |
118 | if (!MagicWrap || curY >= FrameRows - 1) | |
119 | abort (); | |
120 | if (termscript) | |
121 | putc ('\r', termscript); | |
122 | putchar ('\r'); | |
123 | if (termscript) | |
124 | putc ('\n', termscript); | |
125 | putchar ('\n'); | |
126 | curX = 0; | |
127 | curY++; | |
128 | } | |
129 | } | |
130 | ||
131 | ||
d427b66a JB |
132 | /* |
133 | * (Re)Initialize the cost factors, given the output speed of the terminal | |
134 | * in the variable ospeed. (Note: this holds B300, B9600, etc -- ie stuff | |
135 | * out of <sgtty.h>.) | |
136 | */ | |
137 | ||
138 | cmcostinit () | |
139 | { | |
140 | char *p; | |
141 | ||
142 | #define COST(x,e) (x ? (cost = 0, tputs (x, 1, e), cost) : BIG) | |
143 | #define CMCOST(x,e) ((x == 0) ? BIG : (p = tgoto(x, 0, 0), COST(p ,e))) | |
144 | ||
145 | Wcm.cc_up = COST (Wcm.cm_up, evalcost); | |
146 | Wcm.cc_down = COST (Wcm.cm_down, evalcost); | |
147 | Wcm.cc_left = COST (Wcm.cm_left, evalcost); | |
148 | Wcm.cc_right = COST (Wcm.cm_right, evalcost); | |
149 | Wcm.cc_home = COST (Wcm.cm_home, evalcost); | |
150 | Wcm.cc_cr = COST (Wcm.cm_cr, evalcost); | |
151 | Wcm.cc_ll = COST (Wcm.cm_ll, evalcost); | |
152 | Wcm.cc_tab = Wcm.cm_tabwidth ? COST (Wcm.cm_tab, evalcost) : BIG; | |
153 | ||
154 | /* | |
155 | * These last three are actually minimum costs. When (if) they are | |
156 | * candidates for the least-cost motion, the real cost is computed. | |
157 | * (Note that "0" is the assumed to generate the minimum cost. | |
158 | * While this is not necessarily true, I have yet to see a terminal | |
159 | * for which is not; all the terminals that have variable-cost | |
160 | * cursor motion seem to take straight numeric values. --ACT) | |
161 | */ | |
162 | ||
163 | Wcm.cc_abs = CMCOST (Wcm.cm_abs, evalcost); | |
164 | Wcm.cc_habs = CMCOST (Wcm.cm_habs, evalcost); | |
165 | Wcm.cc_vabs = CMCOST (Wcm.cm_vabs, evalcost); | |
166 | ||
167 | #undef CMCOST | |
168 | #undef COST | |
169 | } | |
170 | ||
171 | /* | |
172 | * Calculate the cost to move from (srcy, srcx) to (dsty, dstx) using | |
173 | * up and down, and left and right, motions, and tabs. If doit is set | |
174 | * actually perform the motion. | |
175 | */ | |
176 | ||
177 | static | |
178 | calccost (srcy, srcx, dsty, dstx, doit) | |
179 | { | |
180 | register int deltay, | |
181 | deltax, | |
182 | c, | |
183 | totalcost; | |
184 | int ntabs, | |
185 | n2tabs, | |
186 | tabx, | |
187 | tab2x, | |
188 | tabcost; | |
189 | register char *p; | |
190 | ||
191 | /* If have just wrapped on a terminal with xn, | |
192 | don't believe the cursor position: give up here | |
193 | and force use of absolute positioning. */ | |
194 | ||
195 | if (curX == Wcm.cm_cols) | |
196 | goto fail; | |
197 | ||
198 | totalcost = 0; | |
199 | if ((deltay = dsty - srcy) == 0) | |
200 | goto x; | |
201 | if (deltay < 0) | |
202 | p = Wcm.cm_up, c = Wcm.cc_up, deltay = -deltay; | |
203 | else | |
204 | p = Wcm.cm_down, c = Wcm.cc_down; | |
205 | if (c == BIG) { /* caint get thar from here */ | |
206 | if (doit) | |
207 | printf ("OOPS"); | |
208 | return c; | |
209 | } | |
210 | totalcost = c * deltay; | |
211 | if (doit) | |
212 | while (--deltay >= 0) | |
213 | tputs (p, 1, cmputc); | |
214 | x: | |
215 | if ((deltax = dstx - srcx) == 0) | |
216 | goto done; | |
217 | if (deltax < 0) { | |
218 | p = Wcm.cm_left, c = Wcm.cc_left, deltax = -deltax; | |
219 | goto dodelta; /* skip all the tab junk */ | |
220 | } | |
221 | /* Tabs (the toughie) */ | |
222 | if (Wcm.cc_tab >= BIG || !Wcm.cm_usetabs) | |
223 | goto olddelta; /* forget it! */ | |
224 | ||
225 | /* | |
226 | * ntabs is # tabs towards but not past dstx; n2tabs is one more | |
227 | * (ie past dstx), but this is only valid if that is not past the | |
228 | * right edge of the screen. We can check that at the same time | |
229 | * as we figure out where we would be if we use the tabs (which | |
230 | * we will put into tabx (for ntabs) and tab2x (for n2tabs)). | |
231 | */ | |
232 | ||
233 | ntabs = (deltax + srcx % Wcm.cm_tabwidth) / Wcm.cm_tabwidth; | |
234 | n2tabs = ntabs + 1; | |
235 | tabx = (srcx / Wcm.cm_tabwidth + ntabs) * Wcm.cm_tabwidth; | |
236 | tab2x = tabx + Wcm.cm_tabwidth; | |
237 | ||
238 | if (tab2x >= Wcm.cm_cols) /* too far (past edge) */ | |
239 | n2tabs = 0; | |
240 | ||
241 | /* | |
242 | * Now set tabcost to the cost for using ntabs, and c to the cost | |
243 | * for using n2tabs, then pick the minimum. | |
244 | */ | |
245 | ||
246 | /* cost for ntabs + cost for right motion */ | |
247 | tabcost = ntabs ? ntabs * Wcm.cc_tab + (dstx - tabx) * Wcm.cc_right | |
248 | : BIG; | |
249 | ||
250 | /* cost for n2tabs + cost for left motion */ | |
251 | c = n2tabs ? n2tabs * Wcm.cc_tab + (tab2x - dstx) * Wcm.cc_left | |
252 | : BIG; | |
253 | ||
254 | if (c < tabcost) /* then cheaper to overshoot & back up */ | |
255 | ntabs = n2tabs, tabcost = c, tabx = tab2x; | |
256 | ||
257 | if (tabcost >= BIG) /* caint use tabs */ | |
258 | goto newdelta; | |
259 | ||
260 | /* | |
261 | * See if tabcost is less than just moving right | |
262 | */ | |
263 | ||
264 | if (tabcost < (deltax * Wcm.cc_right)) { | |
265 | totalcost += tabcost; /* use the tabs */ | |
266 | if (doit) | |
267 | while (--ntabs >= 0) | |
268 | tputs (Wcm.cm_tab, 1, cmputc); | |
269 | srcx = tabx; | |
270 | } | |
271 | ||
272 | /* | |
273 | * Now might as well just recompute the delta. | |
274 | */ | |
275 | ||
276 | newdelta: | |
277 | if ((deltax = dstx - srcx) == 0) | |
278 | goto done; | |
279 | olddelta: | |
280 | if (deltax > 0) | |
281 | p = Wcm.cm_right, c = Wcm.cc_right; | |
282 | else | |
283 | p = Wcm.cm_left, c = Wcm.cc_left, deltax = -deltax; | |
284 | ||
285 | dodelta: | |
286 | if (c == BIG) { /* caint get thar from here */ | |
287 | fail: | |
288 | if (doit) | |
289 | printf ("OOPS"); | |
290 | return BIG; | |
291 | } | |
292 | totalcost += c * deltax; | |
293 | if (doit) | |
294 | while (--deltax >= 0) | |
295 | tputs (p, 1, cmputc); | |
296 | done: | |
297 | return totalcost; | |
298 | } | |
299 | ||
300 | #if 0 | |
301 | losecursor () | |
302 | { | |
303 | curY = -1; | |
304 | } | |
305 | #endif | |
306 | ||
307 | #define USEREL 0 | |
308 | #define USEHOME 1 | |
309 | #define USELL 2 | |
310 | #define USECR 3 | |
311 | ||
312 | cmgoto (row, col) | |
313 | { | |
314 | int homecost, | |
315 | crcost, | |
316 | llcost, | |
317 | relcost, | |
318 | directcost; | |
319 | int use; | |
320 | char *p, | |
321 | *dcm; | |
322 | ||
323 | /* First the degenerate case */ | |
324 | if (row == curY && col == curX) /* already there */ | |
325 | return; | |
326 | ||
327 | if (curY >= 0 && curX >= 0) | |
328 | { | |
329 | /* We may have quick ways to go to the upper-left, bottom-left, | |
330 | * start-of-line, or start-of-next-line. Or it might be best to | |
331 | * start where we are. Examine the options, and pick the cheapest. | |
332 | */ | |
333 | ||
334 | relcost = calccost (curY, curX, row, col, 0); | |
335 | use = USEREL; | |
336 | if ((homecost = Wcm.cc_home) < BIG) | |
337 | homecost += calccost (0, 0, row, col, 0); | |
338 | if (homecost < relcost) | |
339 | relcost = homecost, use = USEHOME; | |
340 | if ((llcost = Wcm.cc_ll) < BIG) | |
341 | llcost += calccost (Wcm.cm_rows - 1, 0, row, col, 0); | |
342 | if (llcost < relcost) | |
343 | relcost = llcost, use = USELL; | |
344 | if ((crcost = Wcm.cc_cr) < BIG) { | |
345 | if (Wcm.cm_autolf) | |
346 | if (curY + 1 >= Wcm.cm_rows) | |
347 | crcost = BIG; | |
348 | else | |
349 | crcost += calccost (curY + 1, 0, row, col, 0); | |
350 | else | |
351 | crcost += calccost (curY, 0, row, col, 0); | |
352 | } | |
353 | if (crcost < relcost) | |
354 | relcost = crcost, use = USECR; | |
355 | directcost = Wcm.cc_abs, dcm = Wcm.cm_abs; | |
356 | if (row == curY && Wcm.cc_habs < BIG) | |
357 | directcost = Wcm.cc_habs, dcm = Wcm.cm_habs; | |
358 | else if (col == curX && Wcm.cc_vabs < BIG) | |
359 | directcost = Wcm.cc_vabs, dcm = Wcm.cm_vabs; | |
360 | } | |
361 | else | |
362 | { | |
363 | directcost = 0, relcost = 100000; | |
364 | dcm = Wcm.cm_abs; | |
365 | } | |
366 | ||
367 | /* | |
368 | * In the following comparison, the = in <= is because when the costs | |
369 | * are the same, it looks nicer (I think) to move directly there. | |
370 | */ | |
371 | if (directcost <= relcost) | |
372 | { | |
373 | /* compute REAL direct cost */ | |
374 | cost = 0; | |
375 | p = dcm == Wcm.cm_habs ? tgoto (dcm, row, col) : | |
376 | tgoto (dcm, col, row); | |
377 | tputs (p, 1, evalcost); | |
378 | if (cost <= relcost) | |
379 | { /* really is cheaper */ | |
380 | tputs (p, 1, cmputc); | |
381 | curY = row, curX = col; | |
382 | return; | |
383 | } | |
384 | } | |
385 | ||
386 | switch (use) | |
387 | { | |
388 | case USEHOME: | |
389 | tputs (Wcm.cm_home, 1, cmputc); | |
390 | curY = 0, curX = 0; | |
391 | break; | |
392 | ||
393 | case USELL: | |
394 | tputs (Wcm.cm_ll, 1, cmputc); | |
395 | curY = Wcm.cm_rows - 1, curX = 0; | |
396 | break; | |
397 | ||
398 | case USECR: | |
399 | tputs (Wcm.cm_cr, 1, cmputc); | |
400 | if (Wcm.cm_autolf) | |
401 | curY++; | |
402 | curX = 0; | |
403 | break; | |
404 | } | |
405 | ||
406 | (void) calccost (curY, curX, row, col, 1); | |
407 | curY = row, curX = col; | |
408 | } | |
409 | ||
410 | /* Clear out all terminal info. | |
411 | Used before copying into it the info on the actual terminal. | |
412 | */ | |
413 | ||
414 | Wcm_clear () | |
415 | { | |
416 | bzero (&Wcm, sizeof Wcm); | |
417 | UP = 0; | |
418 | BC = 0; | |
419 | } | |
420 | ||
421 | /* | |
422 | * Initialized stuff | |
423 | * Return 0 if can do CM. | |
424 | * Return -1 if cannot. | |
425 | * Return -2 if size not specified. | |
426 | */ | |
427 | ||
428 | Wcm_init () | |
429 | { | |
430 | #if 0 | |
431 | if (Wcm.cm_abs && !Wcm.cm_ds) | |
432 | return 0; | |
433 | #endif | |
434 | if (Wcm.cm_abs) | |
435 | return 0; | |
436 | /* Require up and left, and, if no absolute, down and right */ | |
437 | if (!Wcm.cm_up || !Wcm.cm_left) | |
438 | return - 1; | |
439 | if (!Wcm.cm_abs && (!Wcm.cm_down || !Wcm.cm_right)) | |
440 | return - 1; | |
441 | /* Check that we know the size of the screen.... */ | |
442 | if (Wcm.cm_rows <= 0 || Wcm.cm_cols <= 0) | |
443 | return - 2; | |
444 | return 0; | |
445 | } |