xref: /freebsd/sys/dev/syscons/schistory.c (revision 685dc743dc3b5645e34836464128e1c0558b404b)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1999 Kazutaka YOKOTA <yokota@zodiac.mech.utsunomiya-u.ac.jp>
5  * Copyright (c) 1992-1998 Søren Schmidt
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer,
13  *    without modification, immediately at the beginning of the file.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
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(__powerpc__)
46 #include <machine/sc_machdep.h>
47 #else
48 #include <machine/pc/display.h>
49 #endif
50 
51 #include <dev/syscons/syscons.h>
52 
53 /*
54  * XXX Placeholder.
55  * This calculations should be dynamically scaled by number of separate sc
56  * devices.  A base value of 'extra_history_size' should be defined for
57  * each syscons unit, and added and subtracted from the dynamic
58  * 'extra_history_size' as units are added and removed.  This way, each time
59  * a new syscons unit goes online, extra_history_size is automatically bumped.
60  */
61 #define	MAXSC	1
62 
63 #if !defined(SC_MAX_HISTORY_SIZE)
64 #define SC_MAX_HISTORY_SIZE	(1000 * MAXCONS * MAXSC)
65 #endif
66 
67 #if !defined(SC_HISTORY_SIZE)
68 #define SC_HISTORY_SIZE		(ROW * 4)
69 #endif
70 
71 #if (SC_HISTORY_SIZE * MAXCONS * MAXSC) > SC_MAX_HISTORY_SIZE
72 #undef SC_MAX_HISTORY_SIZE
73 #define SC_MAX_HISTORY_SIZE	(SC_HISTORY_SIZE * MAXCONS * MAXSC)
74 #endif
75 
76 /* local variables */
77 static int		extra_history_size
78 				= SC_MAX_HISTORY_SIZE - SC_HISTORY_SIZE*MAXCONS;
79 
80 /* local functions */
81 static void copy_history(sc_vtb_t *from, sc_vtb_t *to);
82 static void history_to_screen(scr_stat *scp);
83 
84 /* allocate a history buffer */
85 int
sc_alloc_history_buffer(scr_stat * scp,int lines,int prev_ysize,int wait)86 sc_alloc_history_buffer(scr_stat *scp, int lines, int prev_ysize, int wait)
87 {
88 	/*
89 	 * syscons unconditionally allocates buffers up to
90 	 * SC_HISTORY_SIZE lines or scp->ysize lines, whichever
91 	 * is larger. A value greater than that is allowed,
92 	 * subject to extra_history_size.
93 	 */
94 	sc_vtb_t *history;
95 	sc_vtb_t *prev_history;
96 	int cur_lines;				/* current buffer size */
97 	int min_lines;				/* guaranteed buffer size */
98 	int delta;				/* lines to put back */
99 
100 	if (lines <= 0)
101 		lines = SC_HISTORY_SIZE;	/* use the default value */
102 
103 	/* make it at least as large as the screen size */
104 	lines = imax(lines, scp->ysize);
105 
106 	/* remove the history buffer while we update it */
107 	history = prev_history = scp->history;
108 	scp->history = NULL;
109 
110 	/* calculate the amount of lines to put back to extra_history_size */
111 	delta = 0;
112 	if (prev_history) {
113 		cur_lines = sc_vtb_rows(history);
114 		min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
115 		if (cur_lines > min_lines)
116 			delta = cur_lines - min_lines;
117 	}
118 
119 	/* lines up to min_lines are always allowed. */
120 	min_lines = imax(SC_HISTORY_SIZE, scp->ysize);
121 	if (lines > min_lines) {
122 		if (lines - min_lines > extra_history_size + delta) {
123 			/* too many lines are requested */
124 			scp->history = prev_history;
125 			return EINVAL;
126 		}
127 	}
128 
129 	/* allocate a new buffer */
130 	history = (sc_vtb_t *)malloc(sizeof(*history),
131 				     M_DEVBUF,
132 				     (wait) ? M_WAITOK : M_NOWAIT);
133 	if (history != NULL) {
134 		if (lines > min_lines)
135 			extra_history_size -= lines - min_lines;
136 		/* XXX error check? */
137 		sc_vtb_init(history, VTB_RINGBUFFER, scp->xsize, lines,
138 			    NULL, wait);
139 		/* FIXME: XXX no good? */
140 		sc_vtb_clear(history, scp->sc->scr_map[0x20],
141 			     SC_NORM_ATTR << 8);
142 		if (prev_history != NULL)
143 			copy_history(prev_history, history);
144 		scp->history_pos = sc_vtb_tail(history);
145 	} else {
146 		scp->history_pos = 0;
147 	}
148 
149 	/* destroy the previous buffer */
150 	if (prev_history != NULL) {
151 		extra_history_size += delta;
152 		sc_vtb_destroy(prev_history);
153 		free(prev_history, M_DEVBUF);
154 	}
155 
156 	scp->history = history;
157 
158 	return 0;
159 }
160 
161 static void
copy_history(sc_vtb_t * from,sc_vtb_t * to)162 copy_history(sc_vtb_t *from, sc_vtb_t *to)
163 {
164 	int lines;
165 	int cols;
166 	int cols1;
167 	int cols2;
168 	int pos;
169 	int i;
170 
171 	lines = sc_vtb_rows(from);
172 	cols1 = sc_vtb_cols(from);
173 	cols2 = sc_vtb_cols(to);
174 	cols = imin(cols1, cols2);
175 	pos = sc_vtb_tail(from);
176 	for (i = 0; i < lines; ++i) {
177 		sc_vtb_append(from, pos, to, cols);
178 		if (cols < cols2)
179 			sc_vtb_seek(to, sc_vtb_pos(to,
180 						   sc_vtb_tail(to),
181 						   cols2 - cols));
182 		pos = sc_vtb_pos(from, pos, cols1);
183 	}
184 }
185 
186 void
sc_free_history_buffer(scr_stat * scp,int prev_ysize)187 sc_free_history_buffer(scr_stat *scp, int prev_ysize)
188 {
189 	sc_vtb_t *history;
190 	int cur_lines;				/* current buffer size */
191 	int min_lines;				/* guaranteed buffer size */
192 
193 	history = scp->history;
194 	scp->history = NULL;
195 	if (history == NULL)
196 		return;
197 
198 	cur_lines = sc_vtb_rows(history);
199 	min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
200 	extra_history_size += (cur_lines > min_lines) ?
201 				  cur_lines - min_lines : 0;
202 
203 	sc_vtb_destroy(history);
204 	free(history, M_DEVBUF);
205 }
206 
207 /* copy entire screen into the top of the history buffer */
208 void
sc_hist_save(scr_stat * scp)209 sc_hist_save(scr_stat *scp)
210 {
211 	sc_vtb_append(&scp->vtb, 0, scp->history, scp->xsize*scp->ysize);
212 	scp->history_pos = sc_vtb_tail(scp->history);
213 }
214 
215 /* restore the screen by copying from the history buffer */
216 int
sc_hist_restore(scr_stat * scp)217 sc_hist_restore(scr_stat *scp)
218 {
219 	int ret;
220 
221 	if (scp->history_pos != sc_vtb_tail(scp->history)) {
222 		scp->history_pos = sc_vtb_tail(scp->history);
223 		history_to_screen(scp);
224 		ret =  0;
225 	} else {
226 		ret = 1;
227 	}
228 	sc_vtb_seek(scp->history, sc_vtb_pos(scp->history,
229 					     sc_vtb_tail(scp->history),
230 					     -scp->xsize*scp->ysize));
231 	return ret;
232 }
233 
234 /* copy screen-full of saved lines */
235 static void
history_to_screen(scr_stat * scp)236 history_to_screen(scr_stat *scp)
237 {
238 	int pos;
239 	int i;
240 
241 	pos = scp->history_pos;
242 	for (i = 1; i <= scp->ysize; ++i) {
243 		pos = sc_vtb_pos(scp->history, pos, -scp->xsize);
244 		sc_vtb_copy(scp->history, pos,
245 			    &scp->vtb, scp->xsize*(scp->ysize - i),
246 			    scp->xsize);
247 	}
248 	mark_all(scp);
249 }
250 
251 /* go to the tail of the history buffer */
252 void
sc_hist_home(scr_stat * scp)253 sc_hist_home(scr_stat *scp)
254 {
255 	scp->history_pos = sc_vtb_tail(scp->history);
256 	history_to_screen(scp);
257 }
258 
259 /* go to the top of the history buffer */
260 void
sc_hist_end(scr_stat * scp)261 sc_hist_end(scr_stat *scp)
262 {
263 	scp->history_pos = sc_vtb_pos(scp->history, sc_vtb_tail(scp->history),
264 				      scp->xsize*scp->ysize);
265 	history_to_screen(scp);
266 }
267 
268 /* move one line up */
269 int
sc_hist_up_line(scr_stat * scp)270 sc_hist_up_line(scr_stat *scp)
271 {
272 	if (sc_vtb_pos(scp->history, scp->history_pos, -(scp->xsize*scp->ysize))
273 	    == sc_vtb_tail(scp->history))
274 		return -1;
275 	scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
276 				      -scp->xsize);
277 	history_to_screen(scp);
278 	return 0;
279 }
280 
281 /* move one line down */
282 int
sc_hist_down_line(scr_stat * scp)283 sc_hist_down_line(scr_stat *scp)
284 {
285 	if (scp->history_pos == sc_vtb_tail(scp->history))
286 		return -1;
287 	scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
288 				      scp->xsize);
289 	history_to_screen(scp);
290 	return 0;
291 }
292 
293 int
sc_hist_ioctl(struct tty * tp,u_long cmd,caddr_t data,struct thread * td)294 sc_hist_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
295 {
296 	scr_stat *scp;
297 	int error;
298 
299 	switch (cmd) {
300 	case CONS_HISTORY:  	/* set history size */
301 		scp = SC_STAT(tp);
302 		if (*(int *)data <= 0)
303 			return EINVAL;
304 		if (scp->status & BUFFER_SAVED)
305 			return EBUSY;
306 		DPRINTF(5, ("lines:%d, ysize:%d, pool:%d\n",
307 			    *(int *)data, scp->ysize, extra_history_size));
308 		error = sc_alloc_history_buffer(scp,
309 					       imax(*(int *)data, scp->ysize),
310 					       scp->ysize, TRUE);
311 		DPRINTF(5, ("error:%d, rows:%d, pool:%d\n", error,
312 			    sc_vtb_rows(scp->history), extra_history_size));
313 		return error;
314 
315 	case CONS_CLRHIST:
316 		scp = SC_STAT(tp);
317 		sc_vtb_clear(scp->history, scp->sc->scr_map[0x20],
318 		    SC_NORM_ATTR << 8);
319 		return 0;
320 	}
321 
322 	return ENOIOCTL;
323 }
324 
325 #endif /* SC_NO_HISTORY */
326