Fix the bug which always reallocated the cut buffer whenever

the screen mode is changed even if another vty has larger size.
Reallocate the buffer only when the new screen size is larger than
the current cut buffer size.

1 files changed, 18 insertions, 7 deletions

diff --git a/sys/isa/syscons.c b/sys/isa/syscons.c
index 000f9d7..b996d39 100644
--- a/sys/isa/syscons.c
+++ b/sys/isa/syscons.c
@@ -25,7 +25,7 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- *  $Id: syscons.c,v 1.268 1998/08/03 09:09:34 yokota Exp $
+ *  $Id: syscons.c,v 1.269 1998/08/03 09:15:36 yokota Exp $
  */
 
 #include "sc.h"
@@ -184,6 +184,7 @@ static  char		vgaregs[MODE_PARAM_SIZE];
 static  char		vgaregs2[MODE_PARAM_SIZE];
 static  int		rows_offset = 1;
 static	char 		*cut_buffer;
+static	int		cut_buffer_size;
 static	int		mouse_level = 0;	/* sysmouse protocol level */
 static	mousestatus_t	mouse_status = { 0, 0, 0, 0, 0, 0 };
 static  u_short 	mouse_and_mask[16] = {
@@ -720,7 +721,10 @@ scattach(struct isa_device *dev)
     scp = console[0];
 
     if (crtc_vga) {
-    	cut_buffer = (char *)malloc(scp->xsize*scp->ysize, M_DEVBUF, M_NOWAIT);
+	cut_buffer_size = scp->xsize * scp->ysize + 1;
+    	cut_buffer = (char *)malloc(cut_buffer_size, M_DEVBUF, M_NOWAIT);
+	if (cut_buffer != NULL)
+	    cut_buffer[0] = '\0';
     }
 
     scp->scr_buf = (u_short *)malloc(scp->xsize*scp->ysize*sizeof(u_short),
@@ -1289,7 +1293,7 @@ scioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
 		else
 		    psignal(cur_console->mouse_proc, cur_console->mouse_signal);
 	    }
-	    else if (mouse->operation == MOUSE_ACTION) {
+	    else if (mouse->operation == MOUSE_ACTION && cut_buffer != NULL) {
 		/* process button presses */
 		if ((cur_console->mouse_buttons ^ mouse->u.data.buttons) && 
 		    !(cur_console->status & UNKNOWN_MODE)) {
@@ -1356,7 +1360,7 @@ scioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
 		break;
 	    }
 
-	    if (cur_console->status & UNKNOWN_MODE)
+	    if ((cur_console->status & UNKNOWN_MODE) || (cut_buffer == NULL))
 		break;
 
 	    switch (mouse->u.event.id) {
@@ -1641,9 +1645,16 @@ scioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
     	scp->mouse_pos = scp->mouse_oldpos = 
 	    scp->scr_buf + (scp->mouse_ypos / scp->font_size) * scp->xsize 
 	    + scp->mouse_xpos / 8;
-	free(cut_buffer, M_DEVBUF);
-    	cut_buffer = (char *)malloc(scp->xsize*scp->ysize, M_DEVBUF, M_NOWAIT);
-	cut_buffer[0] = 0x00;
+	/* allocate a larger cut buffer if necessary */
+	if ((cut_buffer == NULL)
+	    || (cut_buffer_size < scp->xsize * scp->ysize + 1)) {
+	    if (cut_buffer != NULL)
+		free(cut_buffer, M_DEVBUF);
+	    cut_buffer_size = scp->xsize * scp->ysize + 1;
+	    cut_buffer = (char *)malloc(cut_buffer_size, M_DEVBUF, M_NOWAIT);
+	    if (cut_buffer != NULL)
+		cut_buffer[0] = '\0';
+	}
 	splx(s);
 
 	usp = scp->history;