sys/dev/misc/syscons/schistory.c

   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 */