Commit | Line | Data |
---|---|---|
d427b66a JB |
1 | /* Cursor motion subroutines for GNU Emacs. |
2 | Copyright (C) 1985 Free Software Foundation, Inc. | |
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 | |
9 | the Free Software Foundation; either version 1, or (at your option) | |
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 | |
19 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
20 | ||
21 | ||
22 | #include "config.h" | |
23 | #include <stdio.h> | |
24 | #include "cm.h" | |
25 | #include "termhooks.h" | |
26 | ||
27 | #define BIG 9999 /* 9999 good on VAXen. For 16 bit machines | |
28 | use about 2000.... */ | |
29 | ||
30 | char *tgoto (); | |
31 | ||
32 | extern char *BC, *UP; | |
33 | ||
34 | int cost; /* sums up costs */ | |
35 | ||
36 | /* ARGSUSED */ | |
37 | evalcost (c) | |
38 | char c; | |
39 | { | |
40 | cost++; | |
41 | } | |
42 | ||
43 | void | |
44 | cmputc (c) | |
45 | char c; | |
46 | { | |
47 | if (termscript) | |
48 | fputc (c & 0177, termscript); | |
49 | putchar (c & 0177); | |
50 | } | |
51 | ||
52 | /* NEXT TWO ARE DONE WITH MACROS */ | |
53 | #if 0 | |
54 | /* | |
55 | * Assume the cursor is at row row, column col. Normally used only after | |
56 | * clearing the screen, when the cursor is at (0, 0), but what the heck, | |
57 | * let's let the guy put it anywhere. | |
58 | */ | |
59 | ||
60 | static | |
61 | at (row, col) { | |
62 | curY = row; | |
63 | curX = col; | |
64 | } | |
65 | ||
66 | /* | |
67 | * Add n columns to the current cursor position. | |
68 | */ | |
69 | ||
70 | static | |
71 | addcol (n) { | |
72 | curX += n; | |
73 | ||
74 | /* | |
75 | * If cursor hit edge of screen, what happened? | |
76 | * N.B.: DO NOT!! write past edge of screen. If you do, you | |
77 | * deserve what you get. Furthermore, on terminals with | |
78 | * autowrap (but not magicwrap), don't write in the last column | |
79 | * of the last line. | |
80 | */ | |
81 | ||
82 | if (curX == Wcm.cm_cols) { | |
83 | /* | |
84 | * Well, if magicwrap, still there, past the edge of the | |
85 | * screen (!). If autowrap, on the col 0 of the next line. | |
86 | * Otherwise on last column. | |
87 | */ | |
88 | ||
89 | if (Wcm.cm_magicwrap) | |
90 | ; /* "limbo" */ | |
91 | else if (Wcm.cm_autowrap) { | |
92 | curX = 0; | |
93 | curY++; /* Beware end of screen! */ | |
94 | } | |
95 | else | |
96 | curX--; | |
97 | } | |
98 | } | |
99 | #endif | |
100 | ||
101 | /* | |
102 | * (Re)Initialize the cost factors, given the output speed of the terminal | |
103 | * in the variable ospeed. (Note: this holds B300, B9600, etc -- ie stuff | |
104 | * out of <sgtty.h>.) | |
105 | */ | |
106 | ||
107 | cmcostinit () | |
108 | { | |
109 | char *p; | |
110 | ||
111 | #define COST(x,e) (x ? (cost = 0, tputs (x, 1, e), cost) : BIG) | |
112 | #define CMCOST(x,e) ((x == 0) ? BIG : (p = tgoto(x, 0, 0), COST(p ,e))) | |
113 | ||
114 | Wcm.cc_up = COST (Wcm.cm_up, evalcost); | |
115 | Wcm.cc_down = COST (Wcm.cm_down, evalcost); | |
116 | Wcm.cc_left = COST (Wcm.cm_left, evalcost); | |
117 | Wcm.cc_right = COST (Wcm.cm_right, evalcost); | |
118 | Wcm.cc_home = COST (Wcm.cm_home, evalcost); | |
119 | Wcm.cc_cr = COST (Wcm.cm_cr, evalcost); | |
120 | Wcm.cc_ll = COST (Wcm.cm_ll, evalcost); | |
121 | Wcm.cc_tab = Wcm.cm_tabwidth ? COST (Wcm.cm_tab, evalcost) : BIG; | |
122 | ||
123 | /* | |
124 | * These last three are actually minimum costs. When (if) they are | |
125 | * candidates for the least-cost motion, the real cost is computed. | |
126 | * (Note that "0" is the assumed to generate the minimum cost. | |
127 | * While this is not necessarily true, I have yet to see a terminal | |
128 | * for which is not; all the terminals that have variable-cost | |
129 | * cursor motion seem to take straight numeric values. --ACT) | |
130 | */ | |
131 | ||
132 | Wcm.cc_abs = CMCOST (Wcm.cm_abs, evalcost); | |
133 | Wcm.cc_habs = CMCOST (Wcm.cm_habs, evalcost); | |
134 | Wcm.cc_vabs = CMCOST (Wcm.cm_vabs, evalcost); | |
135 | ||
136 | #undef CMCOST | |
137 | #undef COST | |
138 | } | |
139 | ||
140 | /* | |
141 | * Calculate the cost to move from (srcy, srcx) to (dsty, dstx) using | |
142 | * up and down, and left and right, motions, and tabs. If doit is set | |
143 | * actually perform the motion. | |
144 | */ | |
145 | ||
146 | static | |
147 | calccost (srcy, srcx, dsty, dstx, doit) | |
148 | { | |
149 | register int deltay, | |
150 | deltax, | |
151 | c, | |
152 | totalcost; | |
153 | int ntabs, | |
154 | n2tabs, | |
155 | tabx, | |
156 | tab2x, | |
157 | tabcost; | |
158 | register char *p; | |
159 | ||
160 | /* If have just wrapped on a terminal with xn, | |
161 | don't believe the cursor position: give up here | |
162 | and force use of absolute positioning. */ | |
163 | ||
164 | if (curX == Wcm.cm_cols) | |
165 | goto fail; | |
166 | ||
167 | totalcost = 0; | |
168 | if ((deltay = dsty - srcy) == 0) | |
169 | goto x; | |
170 | if (deltay < 0) | |
171 | p = Wcm.cm_up, c = Wcm.cc_up, deltay = -deltay; | |
172 | else | |
173 | p = Wcm.cm_down, c = Wcm.cc_down; | |
174 | if (c == BIG) { /* caint get thar from here */ | |
175 | if (doit) | |
176 | printf ("OOPS"); | |
177 | return c; | |
178 | } | |
179 | totalcost = c * deltay; | |
180 | if (doit) | |
181 | while (--deltay >= 0) | |
182 | tputs (p, 1, cmputc); | |
183 | x: | |
184 | if ((deltax = dstx - srcx) == 0) | |
185 | goto done; | |
186 | if (deltax < 0) { | |
187 | p = Wcm.cm_left, c = Wcm.cc_left, deltax = -deltax; | |
188 | goto dodelta; /* skip all the tab junk */ | |
189 | } | |
190 | /* Tabs (the toughie) */ | |
191 | if (Wcm.cc_tab >= BIG || !Wcm.cm_usetabs) | |
192 | goto olddelta; /* forget it! */ | |
193 | ||
194 | /* | |
195 | * ntabs is # tabs towards but not past dstx; n2tabs is one more | |
196 | * (ie past dstx), but this is only valid if that is not past the | |
197 | * right edge of the screen. We can check that at the same time | |
198 | * as we figure out where we would be if we use the tabs (which | |
199 | * we will put into tabx (for ntabs) and tab2x (for n2tabs)). | |
200 | */ | |
201 | ||
202 | ntabs = (deltax + srcx % Wcm.cm_tabwidth) / Wcm.cm_tabwidth; | |
203 | n2tabs = ntabs + 1; | |
204 | tabx = (srcx / Wcm.cm_tabwidth + ntabs) * Wcm.cm_tabwidth; | |
205 | tab2x = tabx + Wcm.cm_tabwidth; | |
206 | ||
207 | if (tab2x >= Wcm.cm_cols) /* too far (past edge) */ | |
208 | n2tabs = 0; | |
209 | ||
210 | /* | |
211 | * Now set tabcost to the cost for using ntabs, and c to the cost | |
212 | * for using n2tabs, then pick the minimum. | |
213 | */ | |
214 | ||
215 | /* cost for ntabs + cost for right motion */ | |
216 | tabcost = ntabs ? ntabs * Wcm.cc_tab + (dstx - tabx) * Wcm.cc_right | |
217 | : BIG; | |
218 | ||
219 | /* cost for n2tabs + cost for left motion */ | |
220 | c = n2tabs ? n2tabs * Wcm.cc_tab + (tab2x - dstx) * Wcm.cc_left | |
221 | : BIG; | |
222 | ||
223 | if (c < tabcost) /* then cheaper to overshoot & back up */ | |
224 | ntabs = n2tabs, tabcost = c, tabx = tab2x; | |
225 | ||
226 | if (tabcost >= BIG) /* caint use tabs */ | |
227 | goto newdelta; | |
228 | ||
229 | /* | |
230 | * See if tabcost is less than just moving right | |
231 | */ | |
232 | ||
233 | if (tabcost < (deltax * Wcm.cc_right)) { | |
234 | totalcost += tabcost; /* use the tabs */ | |
235 | if (doit) | |
236 | while (--ntabs >= 0) | |
237 | tputs (Wcm.cm_tab, 1, cmputc); | |
238 | srcx = tabx; | |
239 | } | |
240 | ||
241 | /* | |
242 | * Now might as well just recompute the delta. | |
243 | */ | |
244 | ||
245 | newdelta: | |
246 | if ((deltax = dstx - srcx) == 0) | |
247 | goto done; | |
248 | olddelta: | |
249 | if (deltax > 0) | |
250 | p = Wcm.cm_right, c = Wcm.cc_right; | |
251 | else | |
252 | p = Wcm.cm_left, c = Wcm.cc_left, deltax = -deltax; | |
253 | ||
254 | dodelta: | |
255 | if (c == BIG) { /* caint get thar from here */ | |
256 | fail: | |
257 | if (doit) | |
258 | printf ("OOPS"); | |
259 | return BIG; | |
260 | } | |
261 | totalcost += c * deltax; | |
262 | if (doit) | |
263 | while (--deltax >= 0) | |
264 | tputs (p, 1, cmputc); | |
265 | done: | |
266 | return totalcost; | |
267 | } | |
268 | ||
269 | #if 0 | |
270 | losecursor () | |
271 | { | |
272 | curY = -1; | |
273 | } | |
274 | #endif | |
275 | ||
276 | #define USEREL 0 | |
277 | #define USEHOME 1 | |
278 | #define USELL 2 | |
279 | #define USECR 3 | |
280 | ||
281 | cmgoto (row, col) | |
282 | { | |
283 | int homecost, | |
284 | crcost, | |
285 | llcost, | |
286 | relcost, | |
287 | directcost; | |
288 | int use; | |
289 | char *p, | |
290 | *dcm; | |
291 | ||
292 | /* First the degenerate case */ | |
293 | if (row == curY && col == curX) /* already there */ | |
294 | return; | |
295 | ||
296 | if (curY >= 0 && curX >= 0) | |
297 | { | |
298 | /* We may have quick ways to go to the upper-left, bottom-left, | |
299 | * start-of-line, or start-of-next-line. Or it might be best to | |
300 | * start where we are. Examine the options, and pick the cheapest. | |
301 | */ | |
302 | ||
303 | relcost = calccost (curY, curX, row, col, 0); | |
304 | use = USEREL; | |
305 | if ((homecost = Wcm.cc_home) < BIG) | |
306 | homecost += calccost (0, 0, row, col, 0); | |
307 | if (homecost < relcost) | |
308 | relcost = homecost, use = USEHOME; | |
309 | if ((llcost = Wcm.cc_ll) < BIG) | |
310 | llcost += calccost (Wcm.cm_rows - 1, 0, row, col, 0); | |
311 | if (llcost < relcost) | |
312 | relcost = llcost, use = USELL; | |
313 | if ((crcost = Wcm.cc_cr) < BIG) { | |
314 | if (Wcm.cm_autolf) | |
315 | if (curY + 1 >= Wcm.cm_rows) | |
316 | crcost = BIG; | |
317 | else | |
318 | crcost += calccost (curY + 1, 0, row, col, 0); | |
319 | else | |
320 | crcost += calccost (curY, 0, row, col, 0); | |
321 | } | |
322 | if (crcost < relcost) | |
323 | relcost = crcost, use = USECR; | |
324 | directcost = Wcm.cc_abs, dcm = Wcm.cm_abs; | |
325 | if (row == curY && Wcm.cc_habs < BIG) | |
326 | directcost = Wcm.cc_habs, dcm = Wcm.cm_habs; | |
327 | else if (col == curX && Wcm.cc_vabs < BIG) | |
328 | directcost = Wcm.cc_vabs, dcm = Wcm.cm_vabs; | |
329 | } | |
330 | else | |
331 | { | |
332 | directcost = 0, relcost = 100000; | |
333 | dcm = Wcm.cm_abs; | |
334 | } | |
335 | ||
336 | /* | |
337 | * In the following comparison, the = in <= is because when the costs | |
338 | * are the same, it looks nicer (I think) to move directly there. | |
339 | */ | |
340 | if (directcost <= relcost) | |
341 | { | |
342 | /* compute REAL direct cost */ | |
343 | cost = 0; | |
344 | p = dcm == Wcm.cm_habs ? tgoto (dcm, row, col) : | |
345 | tgoto (dcm, col, row); | |
346 | tputs (p, 1, evalcost); | |
347 | if (cost <= relcost) | |
348 | { /* really is cheaper */ | |
349 | tputs (p, 1, cmputc); | |
350 | curY = row, curX = col; | |
351 | return; | |
352 | } | |
353 | } | |
354 | ||
355 | switch (use) | |
356 | { | |
357 | case USEHOME: | |
358 | tputs (Wcm.cm_home, 1, cmputc); | |
359 | curY = 0, curX = 0; | |
360 | break; | |
361 | ||
362 | case USELL: | |
363 | tputs (Wcm.cm_ll, 1, cmputc); | |
364 | curY = Wcm.cm_rows - 1, curX = 0; | |
365 | break; | |
366 | ||
367 | case USECR: | |
368 | tputs (Wcm.cm_cr, 1, cmputc); | |
369 | if (Wcm.cm_autolf) | |
370 | curY++; | |
371 | curX = 0; | |
372 | break; | |
373 | } | |
374 | ||
375 | (void) calccost (curY, curX, row, col, 1); | |
376 | curY = row, curX = col; | |
377 | } | |
378 | ||
379 | /* Clear out all terminal info. | |
380 | Used before copying into it the info on the actual terminal. | |
381 | */ | |
382 | ||
383 | Wcm_clear () | |
384 | { | |
385 | bzero (&Wcm, sizeof Wcm); | |
386 | UP = 0; | |
387 | BC = 0; | |
388 | } | |
389 | ||
390 | /* | |
391 | * Initialized stuff | |
392 | * Return 0 if can do CM. | |
393 | * Return -1 if cannot. | |
394 | * Return -2 if size not specified. | |
395 | */ | |
396 | ||
397 | Wcm_init () | |
398 | { | |
399 | #if 0 | |
400 | if (Wcm.cm_abs && !Wcm.cm_ds) | |
401 | return 0; | |
402 | #endif | |
403 | if (Wcm.cm_abs) | |
404 | return 0; | |
405 | /* Require up and left, and, if no absolute, down and right */ | |
406 | if (!Wcm.cm_up || !Wcm.cm_left) | |
407 | return - 1; | |
408 | if (!Wcm.cm_abs && (!Wcm.cm_down || !Wcm.cm_right)) | |
409 | return - 1; | |
410 | /* Check that we know the size of the screen.... */ | |
411 | if (Wcm.cm_rows <= 0 || Wcm.cm_cols <= 0) | |
412 | return - 2; | |
413 | return 0; | |
414 | } |