1 files changed, 322 insertions, 0 deletions

diff --git a/sys/dev/syscons/schistory.c b/sys/dev/syscons/schistory.c
new file mode 100644
index 0000000..30cbdfd
--- /dev/null
+++ b/sys/dev/syscons/schistory.c
@@ -0,0 +1,322 @@
+/*-
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#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>
+
+#include <machine/pc/display.h>
+
+#include <dev/syscons/syscons.h>
+
+/*
+ * XXX Placeholder.
+ * This calculations should be dynamically scaled by number of seperate 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 upto 
+	 * 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 upto 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, int flag,
+	      struct thread *td)
+{
+	scr_stat *scp;
+	int error;
+
+	switch (cmd) {
+
+	case CONS_HISTORY:  	/* set history size */
+		scp = SC_STAT(tp->t_dev);
+		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->t_dev);
+		sc_vtb_clear(scp->history, scp->sc->scr_map[0x20],
+		    SC_NORM_ATTR << 8);
+		return 0;
+	}
+
+	return ENOIOCTL;
+}
+
+#endif /* SC_NO_HISTORY */