xref: /freebsd/sys/dev/syscons/schistory.c (revision ab0b9f6b3073e6c4d1dfbf07444d7db67a189a96)
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 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include "opt_syscons.h"
34 
35 #ifndef SC_NO_HISTORY
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/conf.h>
40 #include <sys/consio.h>
41 #include <sys/tty.h>
42 #include <sys/kernel.h>
43 #include <sys/malloc.h>
44 
45 #if defined(__arm__) || defined(__mips__) || \
46 	defined(__powerpc__) || defined(__sparc64__)
47 #include <machine/sc_machdep.h>
48 #else
49 #include <machine/pc/display.h>
50 #endif
51 
52 #include <dev/syscons/syscons.h>
53 
54 /*
55  * XXX Placeholder.
56  * This calculations should be dynamically scaled by number of separate sc
57  * devices.  A base value of 'extra_history_size' should be defined for
58  * each syscons unit, and added and subtracted from the dynamic
59  * 'extra_history_size' as units are added and removed.  This way, each time
60  * a new syscons unit goes online, extra_history_size is automatically bumped.
61  */
62 #define	MAXSC	1
63 
64 #if !defined(SC_MAX_HISTORY_SIZE)
65 #define SC_MAX_HISTORY_SIZE	(1000 * MAXCONS * MAXSC)
66 #endif
67 
68 #if !defined(SC_HISTORY_SIZE)
69 #define SC_HISTORY_SIZE		(ROW * 4)
70 #endif
71 
72 #if (SC_HISTORY_SIZE * MAXCONS * MAXSC) > SC_MAX_HISTORY_SIZE
73 #undef SC_MAX_HISTORY_SIZE
74 #define SC_MAX_HISTORY_SIZE	(SC_HISTORY_SIZE * MAXCONS * MAXSC)
75 #endif
76 
77 /* local variables */
78 static int		extra_history_size
79 				= SC_MAX_HISTORY_SIZE - SC_HISTORY_SIZE*MAXCONS;
80 
81 /* local functions */
82 static void copy_history(sc_vtb_t *from, sc_vtb_t *to);
83 static void history_to_screen(scr_stat *scp);
84 
85 /* allocate a history buffer */
86 int
87 sc_alloc_history_buffer(scr_stat *scp, int lines, int prev_ysize, int wait)
88 {
89 	/*
90 	 * syscons unconditionally allocates buffers up to
91 	 * SC_HISTORY_SIZE lines or scp->ysize lines, whichever
92 	 * is larger. A value greater than that is allowed,
93 	 * subject to extra_history_size.
94 	 */
95 	sc_vtb_t *history;
96 	sc_vtb_t *prev_history;
97 	int cur_lines;				/* current buffer size */
98 	int min_lines;				/* guaranteed buffer size */
99 	int delta;				/* lines to put back */
100 
101 	if (lines <= 0)
102 		lines = SC_HISTORY_SIZE;	/* use the default value */
103 
104 	/* make it at least as large as the screen size */
105 	lines = imax(lines, scp->ysize);
106 
107 	/* remove the history buffer while we update it */
108 	history = prev_history = scp->history;
109 	scp->history = NULL;
110 
111 	/* calculate the amount of lines to put back to extra_history_size */
112 	delta = 0;
113 	if (prev_history) {
114 		cur_lines = sc_vtb_rows(history);
115 		min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
116 		if (cur_lines > min_lines)
117 			delta = cur_lines - min_lines;
118 	}
119 
120 	/* lines up to min_lines are always allowed. */
121 	min_lines = imax(SC_HISTORY_SIZE, scp->ysize);
122 	if (lines > min_lines) {
123 		if (lines - min_lines > extra_history_size + delta) {
124 			/* too many lines are requested */
125 			scp->history = prev_history;
126 			return EINVAL;
127 		}
128 	}
129 
130 	/* allocate a new buffer */
131 	history = (sc_vtb_t *)malloc(sizeof(*history),
132 				     M_DEVBUF,
133 				     (wait) ? M_WAITOK : M_NOWAIT);
134 	if (history != NULL) {
135 		if (lines > min_lines)
136 			extra_history_size -= lines - min_lines;
137 		/* XXX error check? */
138 		sc_vtb_init(history, VTB_RINGBUFFER, scp->xsize, lines,
139 			    NULL, wait);
140 		/* FIXME: XXX no good? */
141 		sc_vtb_clear(history, scp->sc->scr_map[0x20],
142 			     SC_NORM_ATTR << 8);
143 		if (prev_history != NULL)
144 			copy_history(prev_history, history);
145 		scp->history_pos = sc_vtb_tail(history);
146 	} else {
147 		scp->history_pos = 0;
148 	}
149 
150 	/* destroy the previous buffer */
151 	if (prev_history != NULL) {
152 		extra_history_size += delta;
153 		sc_vtb_destroy(prev_history);
154 		free(prev_history, M_DEVBUF);
155 	}
156 
157 	scp->history = history;
158 
159 	return 0;
160 }
161 
162 static void
163 copy_history(sc_vtb_t *from, sc_vtb_t *to)
164 {
165 	int lines;
166 	int cols;
167 	int cols1;
168 	int cols2;
169 	int pos;
170 	int i;
171 
172 	lines = sc_vtb_rows(from);
173 	cols1 = sc_vtb_cols(from);
174 	cols2 = sc_vtb_cols(to);
175 	cols = imin(cols1, cols2);
176 	pos = sc_vtb_tail(from);
177 	for (i = 0; i < lines; ++i) {
178 		sc_vtb_append(from, pos, to, cols);
179 		if (cols < cols2)
180 			sc_vtb_seek(to, sc_vtb_pos(to,
181 						   sc_vtb_tail(to),
182 						   cols2 - cols));
183 		pos = sc_vtb_pos(from, pos, cols1);
184 	}
185 }
186 
187 void
188 sc_free_history_buffer(scr_stat *scp, int prev_ysize)
189 {
190 	sc_vtb_t *history;
191 	int cur_lines;				/* current buffer size */
192 	int min_lines;				/* guaranteed buffer size */
193 
194 	history = scp->history;
195 	scp->history = NULL;
196 	if (history == NULL)
197 		return;
198 
199 	cur_lines = sc_vtb_rows(history);
200 	min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
201 	extra_history_size += (cur_lines > min_lines) ?
202 				  cur_lines - min_lines : 0;
203 
204 	sc_vtb_destroy(history);
205 	free(history, M_DEVBUF);
206 }
207 
208 /* copy entire screen into the top of the history buffer */
209 void
210 sc_hist_save(scr_stat *scp)
211 {
212 	sc_vtb_append(&scp->vtb, 0, scp->history, scp->xsize*scp->ysize);
213 	scp->history_pos = sc_vtb_tail(scp->history);
214 }
215 
216 /* restore the screen by copying from the history buffer */
217 int
218 sc_hist_restore(scr_stat *scp)
219 {
220 	int ret;
221 
222 	if (scp->history_pos != sc_vtb_tail(scp->history)) {
223 		scp->history_pos = sc_vtb_tail(scp->history);
224 		history_to_screen(scp);
225 		ret =  0;
226 	} else {
227 		ret = 1;
228 	}
229 	sc_vtb_seek(scp->history, sc_vtb_pos(scp->history,
230 					     sc_vtb_tail(scp->history),
231 					     -scp->xsize*scp->ysize));
232 	return ret;
233 }
234 
235 /* copy screen-full of saved lines */
236 static void
237 history_to_screen(scr_stat *scp)
238 {
239 	int pos;
240 	int i;
241 
242 	pos = scp->history_pos;
243 	for (i = 1; i <= scp->ysize; ++i) {
244 		pos = sc_vtb_pos(scp->history, pos, -scp->xsize);
245 		sc_vtb_copy(scp->history, pos,
246 			    &scp->vtb, scp->xsize*(scp->ysize - i),
247 			    scp->xsize);
248 	}
249 	mark_all(scp);
250 }
251 
252 /* go to the tail of the history buffer */
253 void
254 sc_hist_home(scr_stat *scp)
255 {
256 	scp->history_pos = sc_vtb_tail(scp->history);
257 	history_to_screen(scp);
258 }
259 
260 /* go to the top of the history buffer */
261 void
262 sc_hist_end(scr_stat *scp)
263 {
264 	scp->history_pos = sc_vtb_pos(scp->history, sc_vtb_tail(scp->history),
265 				      scp->xsize*scp->ysize);
266 	history_to_screen(scp);
267 }
268 
269 /* move one line up */
270 int
271 sc_hist_up_line(scr_stat *scp)
272 {
273 	if (sc_vtb_pos(scp->history, scp->history_pos, -(scp->xsize*scp->ysize))
274 	    == sc_vtb_tail(scp->history))
275 		return -1;
276 	scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
277 				      -scp->xsize);
278 	history_to_screen(scp);
279 	return 0;
280 }
281 
282 /* move one line down */
283 int
284 sc_hist_down_line(scr_stat *scp)
285 {
286 	if (scp->history_pos == sc_vtb_tail(scp->history))
287 		return -1;
288 	scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
289 				      scp->xsize);
290 	history_to_screen(scp);
291 	return 0;
292 }
293 
294 int
295 sc_hist_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
296 {
297 	scr_stat *scp;
298 	int error;
299 
300 	switch (cmd) {
301 
302 	case CONS_HISTORY:  	/* set history size */
303 		scp = SC_STAT(tp);
304 		if (*(int *)data <= 0)
305 			return EINVAL;
306 		if (scp->status & BUFFER_SAVED)
307 			return EBUSY;
308 		DPRINTF(5, ("lines:%d, ysize:%d, pool:%d\n",
309 			    *(int *)data, scp->ysize, extra_history_size));
310 		error = sc_alloc_history_buffer(scp,
311 					       imax(*(int *)data, scp->ysize),
312 					       scp->ysize, TRUE);
313 		DPRINTF(5, ("error:%d, rows:%d, pool:%d\n", error,
314 			    sc_vtb_rows(scp->history), extra_history_size));
315 		return error;
316 
317 	case CONS_CLRHIST:
318 		scp = SC_STAT(tp);
319 		sc_vtb_clear(scp->history, scp->sc->scr_map[0x20],
320 		    SC_NORM_ATTR << 8);
321 		return 0;
322 	}
323 
324 	return ENOIOCTL;
325 }
326 
327 #endif /* SC_NO_HISTORY */
328