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 __FBSDID("$FreeBSD: stable/12/sys/dev/syscons/schistory.c 326255 2017-11-27 14:52:40Z pfg $");
34
35 #include "opt_syscons.h"
36
37 #ifndef SC_NO_HISTORY
38
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/conf.h>
42 #include <sys/consio.h>
43 #include <sys/tty.h>
44 #include <sys/kernel.h>
45 #include <sys/malloc.h>
46
47 #if defined(__arm__) || defined(__mips__) || \
48 defined(__powerpc__) || defined(__sparc64__)
49 #include <machine/sc_machdep.h>
50 #else
51 #include <machine/pc/display.h>
52 #endif
53
54 #include <dev/syscons/syscons.h>
55
56 /*
57 * XXX Placeholder.
58 * This calculations should be dynamically scaled by number of separate sc
59 * devices. A base value of 'extra_history_size' should be defined for
60 * each syscons unit, and added and subtracted from the dynamic
61 * 'extra_history_size' as units are added and removed. This way, each time
62 * a new syscons unit goes online, extra_history_size is automatically bumped.
63 */
64 #define MAXSC 1
65
66 #if !defined(SC_MAX_HISTORY_SIZE)
67 #define SC_MAX_HISTORY_SIZE (1000 * MAXCONS * MAXSC)
68 #endif
69
70 #if !defined(SC_HISTORY_SIZE)
71 #define SC_HISTORY_SIZE (ROW * 4)
72 #endif
73
74 #if (SC_HISTORY_SIZE * MAXCONS * MAXSC) > SC_MAX_HISTORY_SIZE
75 #undef SC_MAX_HISTORY_SIZE
76 #define SC_MAX_HISTORY_SIZE (SC_HISTORY_SIZE * MAXCONS * MAXSC)
77 #endif
78
79 /* local variables */
80 static int extra_history_size
81 = SC_MAX_HISTORY_SIZE - SC_HISTORY_SIZE*MAXCONS;
82
83 /* local functions */
84 static void copy_history(sc_vtb_t *from, sc_vtb_t *to);
85 static void history_to_screen(scr_stat *scp);
86
87 /* allocate a history buffer */
88 int
sc_alloc_history_buffer(scr_stat * scp,int lines,int prev_ysize,int wait)89 sc_alloc_history_buffer(scr_stat *scp, int lines, int prev_ysize, int wait)
90 {
91 /*
92 * syscons unconditionally allocates buffers up to
93 * SC_HISTORY_SIZE lines or scp->ysize lines, whichever
94 * is larger. A value greater than that is allowed,
95 * subject to extra_history_size.
96 */
97 sc_vtb_t *history;
98 sc_vtb_t *prev_history;
99 int cur_lines; /* current buffer size */
100 int min_lines; /* guaranteed buffer size */
101 int delta; /* lines to put back */
102
103 if (lines <= 0)
104 lines = SC_HISTORY_SIZE; /* use the default value */
105
106 /* make it at least as large as the screen size */
107 lines = imax(lines, scp->ysize);
108
109 /* remove the history buffer while we update it */
110 history = prev_history = scp->history;
111 scp->history = NULL;
112
113 /* calculate the amount of lines to put back to extra_history_size */
114 delta = 0;
115 if (prev_history) {
116 cur_lines = sc_vtb_rows(history);
117 min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
118 if (cur_lines > min_lines)
119 delta = cur_lines - min_lines;
120 }
121
122 /* lines up to min_lines are always allowed. */
123 min_lines = imax(SC_HISTORY_SIZE, scp->ysize);
124 if (lines > min_lines) {
125 if (lines - min_lines > extra_history_size + delta) {
126 /* too many lines are requested */
127 scp->history = prev_history;
128 return EINVAL;
129 }
130 }
131
132 /* allocate a new buffer */
133 history = (sc_vtb_t *)malloc(sizeof(*history),
134 M_DEVBUF,
135 (wait) ? M_WAITOK : M_NOWAIT);
136 if (history != NULL) {
137 if (lines > min_lines)
138 extra_history_size -= lines - min_lines;
139 /* XXX error check? */
140 sc_vtb_init(history, VTB_RINGBUFFER, scp->xsize, lines,
141 NULL, wait);
142 /* FIXME: XXX no good? */
143 sc_vtb_clear(history, scp->sc->scr_map[0x20],
144 SC_NORM_ATTR << 8);
145 if (prev_history != NULL)
146 copy_history(prev_history, history);
147 scp->history_pos = sc_vtb_tail(history);
148 } else {
149 scp->history_pos = 0;
150 }
151
152 /* destroy the previous buffer */
153 if (prev_history != NULL) {
154 extra_history_size += delta;
155 sc_vtb_destroy(prev_history);
156 free(prev_history, M_DEVBUF);
157 }
158
159 scp->history = history;
160
161 return 0;
162 }
163
164 static void
copy_history(sc_vtb_t * from,sc_vtb_t * to)165 copy_history(sc_vtb_t *from, sc_vtb_t *to)
166 {
167 int lines;
168 int cols;
169 int cols1;
170 int cols2;
171 int pos;
172 int i;
173
174 lines = sc_vtb_rows(from);
175 cols1 = sc_vtb_cols(from);
176 cols2 = sc_vtb_cols(to);
177 cols = imin(cols1, cols2);
178 pos = sc_vtb_tail(from);
179 for (i = 0; i < lines; ++i) {
180 sc_vtb_append(from, pos, to, cols);
181 if (cols < cols2)
182 sc_vtb_seek(to, sc_vtb_pos(to,
183 sc_vtb_tail(to),
184 cols2 - cols));
185 pos = sc_vtb_pos(from, pos, cols1);
186 }
187 }
188
189 void
sc_free_history_buffer(scr_stat * scp,int prev_ysize)190 sc_free_history_buffer(scr_stat *scp, int prev_ysize)
191 {
192 sc_vtb_t *history;
193 int cur_lines; /* current buffer size */
194 int min_lines; /* guaranteed buffer size */
195
196 history = scp->history;
197 scp->history = NULL;
198 if (history == NULL)
199 return;
200
201 cur_lines = sc_vtb_rows(history);
202 min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
203 extra_history_size += (cur_lines > min_lines) ?
204 cur_lines - min_lines : 0;
205
206 sc_vtb_destroy(history);
207 free(history, M_DEVBUF);
208 }
209
210 /* copy entire screen into the top of the history buffer */
211 void
sc_hist_save(scr_stat * scp)212 sc_hist_save(scr_stat *scp)
213 {
214 sc_vtb_append(&scp->vtb, 0, scp->history, scp->xsize*scp->ysize);
215 scp->history_pos = sc_vtb_tail(scp->history);
216 }
217
218 /* restore the screen by copying from the history buffer */
219 int
sc_hist_restore(scr_stat * scp)220 sc_hist_restore(scr_stat *scp)
221 {
222 int ret;
223
224 if (scp->history_pos != sc_vtb_tail(scp->history)) {
225 scp->history_pos = sc_vtb_tail(scp->history);
226 history_to_screen(scp);
227 ret = 0;
228 } else {
229 ret = 1;
230 }
231 sc_vtb_seek(scp->history, sc_vtb_pos(scp->history,
232 sc_vtb_tail(scp->history),
233 -scp->xsize*scp->ysize));
234 return ret;
235 }
236
237 /* copy screen-full of saved lines */
238 static void
history_to_screen(scr_stat * scp)239 history_to_screen(scr_stat *scp)
240 {
241 int pos;
242 int i;
243
244 pos = scp->history_pos;
245 for (i = 1; i <= scp->ysize; ++i) {
246 pos = sc_vtb_pos(scp->history, pos, -scp->xsize);
247 sc_vtb_copy(scp->history, pos,
248 &scp->vtb, scp->xsize*(scp->ysize - i),
249 scp->xsize);
250 }
251 mark_all(scp);
252 }
253
254 /* go to the tail of the history buffer */
255 void
sc_hist_home(scr_stat * scp)256 sc_hist_home(scr_stat *scp)
257 {
258 scp->history_pos = sc_vtb_tail(scp->history);
259 history_to_screen(scp);
260 }
261
262 /* go to the top of the history buffer */
263 void
sc_hist_end(scr_stat * scp)264 sc_hist_end(scr_stat *scp)
265 {
266 scp->history_pos = sc_vtb_pos(scp->history, sc_vtb_tail(scp->history),
267 scp->xsize*scp->ysize);
268 history_to_screen(scp);
269 }
270
271 /* move one line up */
272 int
sc_hist_up_line(scr_stat * scp)273 sc_hist_up_line(scr_stat *scp)
274 {
275 if (sc_vtb_pos(scp->history, scp->history_pos, -(scp->xsize*scp->ysize))
276 == sc_vtb_tail(scp->history))
277 return -1;
278 scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
279 -scp->xsize);
280 history_to_screen(scp);
281 return 0;
282 }
283
284 /* move one line down */
285 int
sc_hist_down_line(scr_stat * scp)286 sc_hist_down_line(scr_stat *scp)
287 {
288 if (scp->history_pos == sc_vtb_tail(scp->history))
289 return -1;
290 scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
291 scp->xsize);
292 history_to_screen(scp);
293 return 0;
294 }
295
296 int
sc_hist_ioctl(struct tty * tp,u_long cmd,caddr_t data,struct thread * td)297 sc_hist_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
298 {
299 scr_stat *scp;
300 int error;
301
302 switch (cmd) {
303
304 case CONS_HISTORY: /* set history size */
305 scp = SC_STAT(tp);
306 if (*(int *)data <= 0)
307 return EINVAL;
308 if (scp->status & BUFFER_SAVED)
309 return EBUSY;
310 DPRINTF(5, ("lines:%d, ysize:%d, pool:%d\n",
311 *(int *)data, scp->ysize, extra_history_size));
312 error = sc_alloc_history_buffer(scp,
313 imax(*(int *)data, scp->ysize),
314 scp->ysize, TRUE);
315 DPRINTF(5, ("error:%d, rows:%d, pool:%d\n", error,
316 sc_vtb_rows(scp->history), extra_history_size));
317 return error;
318
319 case CONS_CLRHIST:
320 scp = SC_STAT(tp);
321 sc_vtb_clear(scp->history, scp->sc->scr_map[0x20],
322 SC_NORM_ATTR << 8);
323 return 0;
324 }
325
326 return ENOIOCTL;
327 }
328
329 #endif /* SC_NO_HISTORY */
330