xref: /minix/external/bsd/tmux/dist/screen.c (revision ebfedea0)
1 /* $Id: screen.c,v 1.3 2011/08/17 18:48:36 jmmv Exp $ */
2 
3 /*
4  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 
21 #include <netdb.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <unistd.h>
25 
26 #include "tmux.h"
27 
28 void	screen_resize_x(struct screen *, u_int);
29 void	screen_resize_y(struct screen *, u_int);
30 
31 /* Create a new screen. */
32 void
33 screen_init(struct screen *s, u_int sx, u_int sy, u_int hlimit)
34 {
35 	char hn[MAXHOSTNAMELEN];
36 
37 	s->grid = grid_create(sx, sy, hlimit);
38 
39 	if (gethostname(hn, MAXHOSTNAMELEN) == 0)
40 		s->title = xstrdup(hn);
41 	else
42 		s->title = xstrdup("");
43 
44 	s->cstyle = 0;
45 	s->ccolour = xstrdup("");
46 	s->tabs = NULL;
47 
48 	screen_reinit(s);
49 }
50 
51 /* Reinitialise screen. */
52 void
53 screen_reinit(struct screen *s)
54 {
55 	s->cx = 0;
56 	s->cy = 0;
57 
58 	s->rupper = 0;
59 	s->rlower = screen_size_y(s) - 1;
60 
61 	s->mode = MODE_CURSOR | MODE_WRAP;
62 
63 	screen_reset_tabs(s);
64 
65 	grid_clear_lines(s->grid, s->grid->hsize, s->grid->sy);
66 
67 	screen_clear_selection(s);
68 }
69 
70 /* Destroy a screen. */
71 void
72 screen_free(struct screen *s)
73 {
74 	if (s->tabs != NULL)
75 		xfree(s->tabs);
76 	xfree(s->title);
77 	xfree(s->ccolour);
78 	grid_destroy(s->grid);
79 }
80 
81 /* Reset tabs to default, eight spaces apart. */
82 void
83 screen_reset_tabs(struct screen *s)
84 {
85 	u_int	i;
86 
87 	if (s->tabs != NULL)
88 		xfree(s->tabs);
89 
90 	if ((s->tabs = bit_alloc(screen_size_x(s))) == NULL)
91 		fatal("bit_alloc failed");
92 	for (i = 8; i < screen_size_x(s); i += 8)
93 		bit_set(s->tabs, i);
94 }
95 
96 /* Set screen cursor style. */
97 void
98 screen_set_cursor_style(struct screen *s, u_int style)
99 {
100 	if (style <= 4)
101 		s->cstyle = style;
102 }
103 
104 /* Set screen cursor colour. */
105 void
106 screen_set_cursor_colour(struct screen *s, const char *colour_string)
107 {
108 	xfree(s->ccolour);
109 	s->ccolour = xstrdup(colour_string);
110 }
111 
112 /* Set screen title. */
113 void
114 screen_set_title(struct screen *s, const char *title)
115 {
116 	size_t	slen = strlen(title);
117 	char	tmp[slen * 4 + 1];
118 
119 	strvisx(tmp, title, slen, VIS_OCTAL|VIS_TAB|VIS_NL);
120 
121 	xfree(s->title);
122 	s->title = xstrdup(tmp);
123 }
124 
125 /* Resize screen. */
126 void
127 screen_resize(struct screen *s, u_int sx, u_int sy)
128 {
129 	if (sx < 1)
130 		sx = 1;
131 	if (sy < 1)
132 		sy = 1;
133 
134 	if (sx != screen_size_x(s)) {
135 		screen_resize_x(s, sx);
136 
137 		/*
138 		 * It is unclear what should happen to tabs on resize. xterm
139 		 * seems to try and maintain them, rxvt resets them. Resetting
140 		 * is simpler and more reliable so let's do that.
141 		 */
142 		screen_reset_tabs(s);
143 	}
144 
145 	if (sy != screen_size_y(s))
146 		screen_resize_y(s, sy);
147 }
148 
149 void
150 screen_resize_x(struct screen *s, u_int sx)
151 {
152 	struct grid		*gd = s->grid;
153 
154 	if (sx == 0)
155 		fatalx("zero size");
156 
157 	/*
158 	 * Treat resizing horizontally simply: just ensure the cursor is
159 	 * on-screen and change the size. Don't bother to truncate any lines -
160 	 * then the data should be accessible if the size is then incrased.
161 	 *
162 	 * The only potential wrinkle is if UTF-8 double-width characters are
163 	 * left in the last column, but UTF-8 terminals should deal with this
164 	 * sanely.
165 	 */
166 	if (s->cx >= sx)
167 		s->cx = sx - 1;
168 	gd->sx = sx;
169 }
170 
171 void
172 screen_resize_y(struct screen *s, u_int sy)
173 {
174 	struct grid	*gd = s->grid;
175 	u_int		 needed, available, oldy, i;
176 
177 	if (sy == 0)
178 		fatalx("zero size");
179 	oldy = screen_size_y(s);
180 
181 	/*
182 	 * When resizing:
183 	 *
184 	 * If the height is decreasing, delete lines from the bottom until
185 	 * hitting the cursor, then push lines from the top into the history.
186 	 *
187 	 * When increasing, pull as many lines as possible from the history to
188 	 * the top, then fill the remaining with blanks at the bottom.
189 	 */
190 
191 	/* Size decreasing. */
192 	if (sy < oldy) {
193 		needed = oldy - sy;
194 
195 		/* Delete as many lines as possible from the bottom. */
196 		available = oldy - 1 - s->cy;
197 		if (available > 0) {
198 			if (available > needed)
199 				available = needed;
200 			grid_view_delete_lines(gd, oldy - available, available);
201 		}
202 		needed -= available;
203 
204 		/*
205 		 * Now just increase the history size, if possible, to take
206 		 * over the lines which are left. If history is off, delete
207 		 * lines from the top.
208 		 *
209 		 * XXX Should apply history limit?
210 		 */
211 		available = s->cy;
212 		if (gd->flags & GRID_HISTORY)
213 			gd->hsize += needed;
214 		else if (needed > 0 && available > 0) {
215 			if (available > needed)
216 				available = needed;
217 			grid_view_delete_lines(gd, 0, available);
218 		}
219 		s->cy -= needed;
220 	}
221 
222 	/* Resize line arrays. */
223 	gd->linedata = xrealloc(
224 	    gd->linedata, gd->hsize + sy, sizeof *gd->linedata);
225 
226 	/* Size increasing. */
227 	if (sy > oldy) {
228 		needed = sy - oldy;
229 
230 		/*
231 		 * Try to pull as much as possible out of the history, if is
232 		 * is enabled.
233 		 */
234 		available = gd->hsize;
235 		if (gd->flags & GRID_HISTORY && available > 0) {
236 			if (available > needed)
237 				available = needed;
238 			gd->hsize -= available;
239 			s->cy += available;
240 		} else
241 			available = 0;
242 		needed -= available;
243 
244 		/* Then fill the rest in with blanks. */
245 		for (i = gd->hsize + sy - needed; i < gd->hsize + sy; i++)
246 			memset(&gd->linedata[i], 0, sizeof gd->linedata[i]);
247 	}
248 
249 	/* Set the new size, and reset the scroll region. */
250 	gd->sy = sy;
251 	s->rupper = 0;
252 	s->rlower = screen_size_y(s) - 1;
253 }
254 
255 /* Set selection. */
256 void
257 screen_set_selection(struct screen *s, u_int sx, u_int sy,
258     u_int ex, u_int ey, u_int rectflag, struct grid_cell *gc)
259 {
260 	struct screen_sel	*sel = &s->sel;
261 
262 	memcpy(&sel->cell, gc, sizeof sel->cell);
263 	sel->flag = 1;
264 	sel->rectflag = rectflag;
265 
266 	sel->sx = sx; sel->sy = sy;
267 	sel->ex = ex; sel->ey = ey;
268 }
269 
270 /* Clear selection. */
271 void
272 screen_clear_selection(struct screen *s)
273 {
274 	struct screen_sel	*sel = &s->sel;
275 
276 	sel->flag = 0;
277 }
278 
279 /* Check if cell in selection. */
280 int
281 screen_check_selection(struct screen *s, u_int px, u_int py)
282 {
283 	struct screen_sel	*sel = &s->sel;
284 
285 	if (!sel->flag)
286 		return (0);
287 
288 	if (sel->rectflag) {
289 		if (sel->sy < sel->ey) {
290 			/* start line < end line -- downward selection. */
291 			if (py < sel->sy || py > sel->ey)
292 				return (0);
293 		} else if (sel->sy > sel->ey) {
294 			/* start line > end line -- upward selection. */
295 			if (py > sel->sy || py < sel->ey)
296 				return (0);
297 		} else {
298 			/* starting line == ending line. */
299 			if (py != sel->sy)
300 				return (0);
301 		}
302 
303 		/*
304 		 * Need to include the selection start row, but not the cursor
305 		 * row, which means the selection changes depending on which
306 		 * one is on the left.
307 		 */
308 		if (sel->ex < sel->sx) {
309 			/* Cursor (ex) is on the left. */
310 			if (px < sel->ex)
311 				return (0);
312 
313 			if (px > sel->sx)
314 				return (0);
315 		} else {
316 			/* Selection start (sx) is on the left. */
317 			if (px < sel->sx)
318 				return (0);
319 
320 			if (px > sel->ex)
321 				return (0);
322 		}
323 	} else {
324 		/*
325 		 * Like emacs, keep the top-left-most character, and drop the
326 		 * bottom-right-most, regardless of copy direction.
327 		 */
328 		if (sel->sy < sel->ey) {
329 			/* starting line < ending line -- downward selection. */
330 			if (py < sel->sy || py > sel->ey)
331 				return (0);
332 
333 			if ((py == sel->sy && px < sel->sx)
334 			    || (py == sel->ey && px > sel->ex))
335 				return (0);
336 		} else if (sel->sy > sel->ey) {
337 			/* starting line > ending line -- upward selection. */
338 			if (py > sel->sy || py < sel->ey)
339 				return (0);
340 
341 			if ((py == sel->sy && px >= sel->sx)
342 			    || (py == sel->ey && px < sel->ex))
343 				return (0);
344 		} else {
345 			/* starting line == ending line. */
346 			if (py != sel->sy)
347 				return (0);
348 
349 			if (sel->ex < sel->sx) {
350 				/* cursor (ex) is on the left */
351 				if (px > sel->sx || px < sel->ex)
352 					return (0);
353 			} else {
354 				/* selection start (sx) is on the left */
355 				if (px < sel->sx || px > sel->ex)
356 					return (0);
357 			}
358 		}
359 	}
360 
361 	return (1);
362 }
363