freebsd-nq/sys/dev/syscons/schistory.c
2020-09-01 21:29:44 +00:00

328 lines
8.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1999 Kazutaka YOKOTA <yokota@zodiac.mech.utsunomiya-u.ac.jp>
* Copyright (c) 1992-1998 Søren Schmidt
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* without modification, immediately at the beginning of the file.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_syscons.h"
#ifndef SC_NO_HISTORY
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/consio.h>
#include <sys/tty.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#if defined(__arm__) || defined(__mips__) || defined(__powerpc__)
#include <machine/sc_machdep.h>
#else
#include <machine/pc/display.h>
#endif
#include <dev/syscons/syscons.h>
/*
* XXX Placeholder.
* This calculations should be dynamically scaled by number of separate sc
* devices. A base value of 'extra_history_size' should be defined for
* each syscons unit, and added and subtracted from the dynamic
* 'extra_history_size' as units are added and removed. This way, each time
* a new syscons unit goes online, extra_history_size is automatically bumped.
*/
#define MAXSC 1
#if !defined(SC_MAX_HISTORY_SIZE)
#define SC_MAX_HISTORY_SIZE (1000 * MAXCONS * MAXSC)
#endif
#if !defined(SC_HISTORY_SIZE)
#define SC_HISTORY_SIZE (ROW * 4)
#endif
#if (SC_HISTORY_SIZE * MAXCONS * MAXSC) > SC_MAX_HISTORY_SIZE
#undef SC_MAX_HISTORY_SIZE
#define SC_MAX_HISTORY_SIZE (SC_HISTORY_SIZE * MAXCONS * MAXSC)
#endif
/* local variables */
static int extra_history_size
= SC_MAX_HISTORY_SIZE - SC_HISTORY_SIZE*MAXCONS;
/* local functions */
static void copy_history(sc_vtb_t *from, sc_vtb_t *to);
static void history_to_screen(scr_stat *scp);
/* allocate a history buffer */
int
sc_alloc_history_buffer(scr_stat *scp, int lines, int prev_ysize, int wait)
{
/*
* syscons unconditionally allocates buffers up to
* SC_HISTORY_SIZE lines or scp->ysize lines, whichever
* is larger. A value greater than that is allowed,
* subject to extra_history_size.
*/
sc_vtb_t *history;
sc_vtb_t *prev_history;
int cur_lines; /* current buffer size */
int min_lines; /* guaranteed buffer size */
int delta; /* lines to put back */
if (lines <= 0)
lines = SC_HISTORY_SIZE; /* use the default value */
/* make it at least as large as the screen size */
lines = imax(lines, scp->ysize);
/* remove the history buffer while we update it */
history = prev_history = scp->history;
scp->history = NULL;
/* calculate the amount of lines to put back to extra_history_size */
delta = 0;
if (prev_history) {
cur_lines = sc_vtb_rows(history);
min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
if (cur_lines > min_lines)
delta = cur_lines - min_lines;
}
/* lines up to min_lines are always allowed. */
min_lines = imax(SC_HISTORY_SIZE, scp->ysize);
if (lines > min_lines) {
if (lines - min_lines > extra_history_size + delta) {
/* too many lines are requested */
scp->history = prev_history;
return EINVAL;
}
}
/* allocate a new buffer */
history = (sc_vtb_t *)malloc(sizeof(*history),
M_DEVBUF,
(wait) ? M_WAITOK : M_NOWAIT);
if (history != NULL) {
if (lines > min_lines)
extra_history_size -= lines - min_lines;
/* XXX error check? */
sc_vtb_init(history, VTB_RINGBUFFER, scp->xsize, lines,
NULL, wait);
/* FIXME: XXX no good? */
sc_vtb_clear(history, scp->sc->scr_map[0x20],
SC_NORM_ATTR << 8);
if (prev_history != NULL)
copy_history(prev_history, history);
scp->history_pos = sc_vtb_tail(history);
} else {
scp->history_pos = 0;
}
/* destroy the previous buffer */
if (prev_history != NULL) {
extra_history_size += delta;
sc_vtb_destroy(prev_history);
free(prev_history, M_DEVBUF);
}
scp->history = history;
return 0;
}
static void
copy_history(sc_vtb_t *from, sc_vtb_t *to)
{
int lines;
int cols;
int cols1;
int cols2;
int pos;
int i;
lines = sc_vtb_rows(from);
cols1 = sc_vtb_cols(from);
cols2 = sc_vtb_cols(to);
cols = imin(cols1, cols2);
pos = sc_vtb_tail(from);
for (i = 0; i < lines; ++i) {
sc_vtb_append(from, pos, to, cols);
if (cols < cols2)
sc_vtb_seek(to, sc_vtb_pos(to,
sc_vtb_tail(to),
cols2 - cols));
pos = sc_vtb_pos(from, pos, cols1);
}
}
void
sc_free_history_buffer(scr_stat *scp, int prev_ysize)
{
sc_vtb_t *history;
int cur_lines; /* current buffer size */
int min_lines; /* guaranteed buffer size */
history = scp->history;
scp->history = NULL;
if (history == NULL)
return;
cur_lines = sc_vtb_rows(history);
min_lines = imax(SC_HISTORY_SIZE, prev_ysize);
extra_history_size += (cur_lines > min_lines) ?
cur_lines - min_lines : 0;
sc_vtb_destroy(history);
free(history, M_DEVBUF);
}
/* copy entire screen into the top of the history buffer */
void
sc_hist_save(scr_stat *scp)
{
sc_vtb_append(&scp->vtb, 0, scp->history, scp->xsize*scp->ysize);
scp->history_pos = sc_vtb_tail(scp->history);
}
/* restore the screen by copying from the history buffer */
int
sc_hist_restore(scr_stat *scp)
{
int ret;
if (scp->history_pos != sc_vtb_tail(scp->history)) {
scp->history_pos = sc_vtb_tail(scp->history);
history_to_screen(scp);
ret = 0;
} else {
ret = 1;
}
sc_vtb_seek(scp->history, sc_vtb_pos(scp->history,
sc_vtb_tail(scp->history),
-scp->xsize*scp->ysize));
return ret;
}
/* copy screen-full of saved lines */
static void
history_to_screen(scr_stat *scp)
{
int pos;
int i;
pos = scp->history_pos;
for (i = 1; i <= scp->ysize; ++i) {
pos = sc_vtb_pos(scp->history, pos, -scp->xsize);
sc_vtb_copy(scp->history, pos,
&scp->vtb, scp->xsize*(scp->ysize - i),
scp->xsize);
}
mark_all(scp);
}
/* go to the tail of the history buffer */
void
sc_hist_home(scr_stat *scp)
{
scp->history_pos = sc_vtb_tail(scp->history);
history_to_screen(scp);
}
/* go to the top of the history buffer */
void
sc_hist_end(scr_stat *scp)
{
scp->history_pos = sc_vtb_pos(scp->history, sc_vtb_tail(scp->history),
scp->xsize*scp->ysize);
history_to_screen(scp);
}
/* move one line up */
int
sc_hist_up_line(scr_stat *scp)
{
if (sc_vtb_pos(scp->history, scp->history_pos, -(scp->xsize*scp->ysize))
== sc_vtb_tail(scp->history))
return -1;
scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
-scp->xsize);
history_to_screen(scp);
return 0;
}
/* move one line down */
int
sc_hist_down_line(scr_stat *scp)
{
if (scp->history_pos == sc_vtb_tail(scp->history))
return -1;
scp->history_pos = sc_vtb_pos(scp->history, scp->history_pos,
scp->xsize);
history_to_screen(scp);
return 0;
}
int
sc_hist_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
{
scr_stat *scp;
int error;
switch (cmd) {
case CONS_HISTORY: /* set history size */
scp = SC_STAT(tp);
if (*(int *)data <= 0)
return EINVAL;
if (scp->status & BUFFER_SAVED)
return EBUSY;
DPRINTF(5, ("lines:%d, ysize:%d, pool:%d\n",
*(int *)data, scp->ysize, extra_history_size));
error = sc_alloc_history_buffer(scp,
imax(*(int *)data, scp->ysize),
scp->ysize, TRUE);
DPRINTF(5, ("error:%d, rows:%d, pool:%d\n", error,
sc_vtb_rows(scp->history), extra_history_size));
return error;
case CONS_CLRHIST:
scp = SC_STAT(tp);
sc_vtb_clear(scp->history, scp->sc->scr_map[0x20],
SC_NORM_ATTR << 8);
return 0;
}
return ENOIOCTL;
}
#endif /* SC_NO_HISTORY */