From Bruce Evans:

lpt doesn't work here if the printer is not turned on at boot time (this
has been reported for other systems).

lpt has a weird mapping of the flag bits vs printer numbers and MAKEDEV
does not understand this (printer 0 uses minor numbers 0-0x3f, printer 1
uses minors 0x40-0x7f, etc).

The following (simpler) problems are fixed by the patch.

lpt did not check the minor number on open, so if NLPT1 == 1 and you
try to open printer 1 then random memory above the lpt_sc array is
accessed.  I thought I had this problem for minors 1 and 2.  However,
it does not actually occur until minor 0x40.  Does anyone have lpt64?

lpt had several unnecessary && broken ANSIisms and other sloppy
declarations.

Bruce
This commit is contained in:
Rodney W. Grimes 1993-07-13 18:52:49 +00:00
parent f7710986e2
commit 0d01087b28

View File

@ -97,12 +97,13 @@
int lptflag = 1;
#endif
int lptout();
void lptout();
#ifdef DEBUG
int lptflag = 1;
#endif
int lptprobe(), lptattach(), lptintr();
int lptprobe(), lptattach();
void lptintr();
struct isa_driver lptdriver = {
lptprobe, lptattach, "lpt"
@ -143,7 +144,10 @@ struct lpt_softc {
* Internal routine to lptprobe to do port tests of one byte value
*/
int
lpt_port_test(short port, u_char data, u_char mask)
lpt_port_test(port, data, mask)
short port;
u_char data;
u_char mask;
{
int temp, timeout;
@ -182,8 +186,9 @@ lpt_port_test(short port, u_char data, u_char mask)
*/
int
lptprobe(struct isa_device *dvp)
{
lptprobe(dvp)
struct isa_device *dvp;
{
int status;
short port;
u_char data;
@ -227,6 +232,7 @@ lptprobe(struct isa_device *dvp)
return (status);
}
int
lptattach(isdp)
struct isa_device *isdp;
{
@ -242,13 +248,19 @@ lptattach(isdp)
* lptopen -- reset the printer, then wait until it's selected and not busy.
*/
int
lptopen(dev, flag)
dev_t dev;
int flag;
{
struct lpt_softc *sc = lpt_sc + LPTUNIT(minor(dev));
struct lpt_softc *sc;
int s;
int trys, port;
u_int unit = LPTUNIT(minor(dev));
if (unit >= NLPT)
return (ENXIO);
sc = lpt_sc + unit;
if (sc->sc_state) {
lprintf("lp: still open\n") ;
@ -310,6 +322,7 @@ lprintf("opened.\n");
return(0);
}
void
lptout (sc)
struct lpt_softc *sc;
{ int pl;
@ -339,7 +352,9 @@ lprintf ("T %x ", inb(sc->sc_port+lpt_status));
* lptclose -- close the device, free the local line buffer.
*/
int
lptclose(dev, flag)
dev_t dev;
int flag;
{
struct lpt_softc *sc = lpt_sc + LPTUNIT(minor(dev));
@ -365,6 +380,7 @@ lprintf("closed.\n");
* putc to get the chars moved to the output queue.
*/
int
lptwrite(dev, uio)
dev_t dev;
struct uio *uio;
@ -398,7 +414,9 @@ lprintf("W ");
* ready to accept another char.
*/
void
lptintr(unit)
int unit;
{
struct lpt_softc *sc = lpt_sc + unit;
int port = sc->sc_port,sts;
@ -433,7 +451,11 @@ lprintf("sts %x ", sts);
}
int
lptioctl(dev_t dev, int cmd, caddr_t data, int flag)
lptioctl(dev, cmd, data, flag)
dev_t dev;
int cmd;
caddr_t data;
int flag;
{
int error;