xref: /dragonfly/sys/dev/misc/syscons/schistory.c (revision 70675b40)
1 /*-
2  * Copyright (c) 1999 Kazutaka YOKOTA <yokota@zodiac.mech.utsunomiya-u.ac.jp>
3  * Copyright (c) 1992-1998 Søren Schmidt
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer,
11  *    without modification, immediately at the beginning of the file.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  * $FreeBSD: src/sys/dev/syscons/schistory.c,v 1.8.2.1 2001/07/19 06:38:53 dd Exp $
30  * $DragonFly: src/sys/dev/misc/syscons/schistory.c,v 1.8 2006/09/05 00:55:38 dillon Exp $
31  */
32 
33 #include "use_sc.h"
34 #include "opt_syscons.h"
35 
36 #ifndef SC_NO_HISTORY
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/conf.h>
41 #include <sys/tty.h>
42 #include <sys/kernel.h>
43 
44 #include <machine/console.h>
45 #include <machine/pc/display.h>
46 
47 #include "syscons.h"
48 
49 #if !defined(SC_MAX_HISTORY_SIZE)
50 #define SC_MAX_HISTORY_SIZE	(1000 * MAXCONS * NSC)
51 #endif
52 
53 #if !defined(SC_HISTORY_SIZE)
54 #define SC_HISTORY_SIZE		(ROW * 10)
55 #endif
56 
57 #if (SC_HISTORY_SIZE * MAXCONS * NSC) > SC_MAX_HISTORY_SIZE
58 #undef SC_MAX_HISTORY_SIZE
59 #define SC_MAX_HISTORY_SIZE	(SC_HISTORY_SIZE * MAXCONS * NSC)
60 #endif
61 
62 /* local variables */
63 static int extra_history_size = SC_MAX_HISTORY_SIZE - SC_HISTORY_SIZE*MAXCONS;
64 
65 /* local functions */
66 static void copy_history(sc_vtb_t *from, sc_vtb_t *to);
67 static void history_to_screen(scr_stat *scp);
68 static void history_to_screen_lines(scr_stat *scp, int cnt);
69 
70 /* allocate a history buffer */
71 int
72 sc_alloc_history_buffer(scr_stat *scp, int lines, int prev_ysize, int wait)
73 {
74 	/*
75 	 * syscons unconditionally allocates buffers upto
76 	 * SC_HISTORY_SIZE lines or scp->ysize lines, whichever
77 	 * is larger. A value greater than that is allowed,
78 	 * subject to extra_history_size.
79 	 */
80 	sc_vtb_t *history;
81 	sc_vtb_t *prev_history;
82 	int cur_lines;				/* current buffer size */
83 	int min_lines;				/* guaranteed buffer size */
84 	int delta;				/* lines to put back */
85 	int ok;
86 
87 	if (lines <= 0)
88 		lines = SC_HISTORY_SIZE;	/* use the default value */
89 
90 	/* make it at least as large as the screen size */
91 	lines = imax(lines, scp->ysize);
92 
93 	/* remove the history buffer while we update it */
94 	history = prev_history = scp->history;
95 	scp->history = NULL;
96 
97 	/* calculate the amount of lines to put back to extra_history_size */
98 	delta = 0;
99 	if (prev_history) {
100 		cur_lines = sc_vtb_rows(history);
101 		min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
102 		if (cur_lines > min_lines)
103 			delta = cur_lines - min_lines;
104 	}
105 
106 	/* lines upto min_lines are always allowed. */
107 	min_lines = imax(SC_HISTORY_SIZE, scp->ysize);
108 	if (lines > min_lines) {
109 		if (lines - min_lines > extra_history_size + delta) {
110 			/* too many lines are requested */
111 			scp->history = prev_history;
112 			return EINVAL;
113 		}
114 	}
115 
116 	/* allocate a new buffer */
117 	ok = 0;
118 	history = kmalloc(sizeof(*history), M_SYSCONS,
119 			 (wait) ? M_WAITOK : M_NOWAIT);
120 	if (history != NULL) {
121 		if (lines > min_lines)
122 			extra_history_size -= lines - min_lines;
123 		/* XXX error check? */
124 		sc_vtb_init(history, VTB_RINGBUFFER, scp->xsize, lines,
125 			    NULL, wait);
126 		if (history->vtb_flags & VTB_VALID) {
127 			/* FIXME: XXX no good? */
128 			sc_vtb_clear(history, scp->sc->scr_map[0x20],
129 				     SC_NORM_ATTR << 8);
130 			if (prev_history != NULL)
131 				copy_history(prev_history, history);
132 			scp->history_pos = sc_vtb_tail(history);
133 			ok = 1;
134 		}
135 	}
136 
137 	if (ok) {
138 		/*
139 		 * Install new buffer, destroy previous buffer
140 		 */
141 		if (prev_history != NULL) {
142 			extra_history_size += delta;
143 			sc_vtb_destroy(prev_history);
144 			kfree(prev_history, M_SYSCONS);
145 		}
146 		scp->history = history;
147 	} else {
148 		/*
149 		 * Destroy partially initialized new buffer, keep
150 		 * previous buffer.   Anything could have happened
151 		 * in the mean time so reset the history position.
152 		 */
153 		if (history) {
154 			sc_vtb_destroy(history);
155 			kfree(history, M_SYSCONS);
156 		}
157 		scp->history_pos = 0;
158 		scp->history = prev_history;
159 	}
160 	return 0;
161 }
162 
163 static void
164 copy_history(sc_vtb_t *from, sc_vtb_t *to)
165 {
166 	int lines;
167 	int cols;
168 	int cols1;
169 	int cols2;
170 	int pos;
171 	int i;
172 
173 	lines = sc_vtb_rows(from);
174 	cols1 = sc_vtb_cols(from);
175 	cols2 = sc_vtb_cols(to);
176 	cols = imin(cols1, cols2);
177 	pos = sc_vtb_tail(from);
178 	for (i = 0; i < lines; ++i) {
179 		sc_vtb_append(from, pos, to, cols);
180 		if (cols < cols2)
181 			sc_vtb_seek(to, sc_vtb_pos(to,
182 						   sc_vtb_tail(to),
183 						   cols2 - cols));
184 		pos = sc_vtb_pos(from, pos, cols1);
185 	}
186 }
187 
188 void
189 sc_free_history_buffer(scr_stat *scp, int prev_ysize)
190 {
191 	sc_vtb_t *history;
192 	int cur_lines;				/* current buffer size */
193 	int min_lines;				/* guaranteed buffer size */
194 
195 	history = scp->history;
196 	scp->history = NULL;
197 	if (history == NULL)
198 		return;
199 
200 	cur_lines = sc_vtb_rows(history);
201 	min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
202 	extra_history_size += (cur_lines > min_lines) ?
203 				  cur_lines - min_lines : 0;
204 
205 	sc_vtb_destroy(history);
206 	kfree(history, M_SYSCONS);
207 }
208 
209 /* copy entire screen into the top of the history buffer */
210 void
211 sc_hist_save(scr_stat *scp)
212 {
213 	sc_vtb_append(&scp->vtb, 0, scp->history, scp->xsize*scp->ysize);
214 	scp->history_pos = sc_vtb_tail(scp->history);
215 }
216 
217 /* restore the screen by copying from the history buffer */
218 int
219 sc_hist_restore(scr_stat *scp)
220 {
221 	int ret;
222 
223 	if (scp->history_pos != sc_vtb_tail(scp->history)) {
224 		scp->history_pos = sc_vtb_tail(scp->history);
225 		history_to_screen(scp);
226 		ret =  0;
227 	} else {
228 		ret = 1;
229 	}
230 	sc_vtb_seek(scp->history, sc_vtb_pos(scp->history,
231 					     sc_vtb_tail(scp->history),
232 					     -scp->xsize*scp->ysize));
233 	return ret;
234 }
235 
236 /* copy screen-full of saved lines */
237 static void
238 history_to_screen(scr_stat *scp)
239 {
240 	history_to_screen_lines(scp, scp->ysize);
241 }
242 
243 /* copy cnt of saved lines */
244 static void
245 history_to_screen_lines(scr_stat *scp, int cnt)
246 {
247 	int pos;
248 	int i;
249 	int lines = imin(cnt, scp->ysize);
250 
251 	pos = scp->history_pos;
252 	for (i = 1; i <= lines; ++i) {
253 		pos = sc_vtb_pos(scp->history, pos, -scp->xsize);
254 		sc_vtb_copy(scp->history, pos,
255 			    &scp->vtb, scp->xsize*(lines - i),
256 			    scp->xsize);
257 	}
258 	mark_all(scp);
259 }
260 
261 /* go to the tail of the history buffer */
262 void
263 sc_hist_home(scr_stat *scp)
264 {
265 	scp->history_pos = sc_vtb_tail(scp->history);
266 	history_to_screen(scp);
267 }
268 
269 /* Restore old_ysize lines from the tail of the history buffer */
270 void
271 sc_hist_getback(scr_stat *scp, int old_ysize)
272 {
273 	scp->history_pos = sc_vtb_tail(scp->history);
274 	history_to_screen_lines(scp, old_ysize);
275 }
276 
277 /* go to the top of the history buffer */
278 void
279 sc_hist_end(scr_stat *scp)
280 {
281 	scp->history_pos = sc_vtb_pos(scp->history, sc_vtb_tail(scp->history),
282 				      scp->xsize*scp->ysize);
283 	history_to_screen(scp);
284 }
285 
286 /* move one line up */
287 int
288 sc_hist_up_line(scr_stat *scp)
289 {
290 	if (sc_vtb_pos(scp->history, scp->history_pos, -(scp->xsize*scp->ysize))
291 	    == sc_vtb_tail(scp->history))
292 		return -1;
293 	scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
294 				      -scp->xsize);
295 	history_to_screen(scp);
296 	return 0;
297 }
298 
299 /* move one line down */
300 int
301 sc_hist_down_line(scr_stat *scp)
302 {
303 	if (scp->history_pos == sc_vtb_tail(scp->history))
304 		return -1;
305 	scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
306 				      scp->xsize);
307 	history_to_screen(scp);
308 	return 0;
309 }
310 
311 int
312 sc_hist_ioctl(struct tty *tp, u_long cmd, caddr_t data, int flag)
313 {
314 	scr_stat *scp;
315 	int error;
316 
317 	switch (cmd) {
318 
319 	case CONS_HISTORY:  	/* set history size */
320 		scp = SC_STAT(tp->t_dev);
321 		if (*(int *)data <= 0)
322 			return EINVAL;
323 		if (scp->status & BUFFER_SAVED)
324 			return EBUSY;
325 		DPRINTF(5, ("lines:%d, ysize:%d, pool:%d\n",
326 			    *(int *)data, scp->ysize, extra_history_size));
327 		error = sc_alloc_history_buffer(scp,
328 					       imax(*(int *)data, scp->ysize),
329 					       scp->ysize, TRUE);
330 		DPRINTF(5, ("error:%d, rows:%d, pool:%d\n", error,
331 			    sc_vtb_rows(scp->history), extra_history_size));
332 		return error;
333 
334 	case CONS_CLRHIST:
335 		scp = SC_STAT(tp->t_dev);
336 		sc_vtb_clear(scp->history, scp->sc->scr_map[0x20],
337 		    SC_NORM_ATTR << 8);
338 		return 0;
339 	}
340 
341 	return ENOIOCTL;
342 }
343 
344 #endif /* SC_NO_HISTORY */
345