sys/dev/syscons/schistory.c

   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("$FreeBSD$");
  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
  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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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 */