mirror of https://github.com/lianthony/NT4.0
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
100 lines
1.9 KiB
100 lines
1.9 KiB
/*[
|
|
|
|
verr.c
|
|
|
|
LOCAL CHAR SccsID[]="@(#)verr.c 1.5 02/09/94";
|
|
|
|
VERR CPU Functions.
|
|
-------------------
|
|
|
|
]*/
|
|
|
|
|
|
#include <insignia.h>
|
|
|
|
#include <host_def.h>
|
|
#include <xt.h>
|
|
#include <c_main.h>
|
|
#include <c_addr.h>
|
|
#include <c_bsic.h>
|
|
#include <c_prot.h>
|
|
#include <c_seg.h>
|
|
#include <c_stack.h>
|
|
#include <c_xcptn.h>
|
|
#include <c_reg.h>
|
|
#include <verr.h>
|
|
#include <c_page.h>
|
|
|
|
|
|
/*
|
|
=====================================================================
|
|
EXTERNAL ROUTINES START HERE
|
|
=====================================================================
|
|
*/
|
|
|
|
|
|
GLOBAL VOID
|
|
VERR
|
|
|
|
IFN1(
|
|
IU32, op1 /* src(selector) operand */
|
|
)
|
|
|
|
|
|
{
|
|
BOOL readable = FALSE;
|
|
IU32 descr;
|
|
IU8 AR;
|
|
|
|
if ( !selector_outside_GDT_LDT((IU16)op1, &descr) )
|
|
{
|
|
/* get access rights */
|
|
AR = spr_read_byte(descr+5);
|
|
|
|
/* Handle each type of descriptor */
|
|
switch ( descriptor_super_type((IU16)AR) )
|
|
{
|
|
case INVALID:
|
|
case AVAILABLE_TSS:
|
|
case LDT_SEGMENT:
|
|
case BUSY_TSS:
|
|
case CALL_GATE:
|
|
case TASK_GATE:
|
|
case INTERRUPT_GATE:
|
|
case TRAP_GATE:
|
|
case XTND_AVAILABLE_TSS:
|
|
case XTND_BUSY_TSS:
|
|
case XTND_CALL_GATE:
|
|
case XTND_INTERRUPT_GATE:
|
|
case XTND_TRAP_GATE:
|
|
case CONFORM_NOREAD_CODE:
|
|
case NONCONFORM_NOREAD_CODE:
|
|
break; /* never readable */
|
|
|
|
case CONFORM_READABLE_CODE:
|
|
readable = TRUE; /* always readable */
|
|
break;
|
|
|
|
case EXPANDUP_READONLY_DATA:
|
|
case EXPANDUP_WRITEABLE_DATA:
|
|
case EXPANDDOWN_READONLY_DATA:
|
|
case EXPANDDOWN_WRITEABLE_DATA:
|
|
case NONCONFORM_READABLE_CODE:
|
|
/* access depends on privilege, it is required that
|
|
DPL >= CPL and DPL >= RPL */
|
|
if ( GET_AR_DPL(AR) >= GET_CPL() &&
|
|
GET_AR_DPL(AR) >= GET_SELECTOR_RPL(op1) )
|
|
readable = TRUE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if ( readable )
|
|
{
|
|
SET_ZF(1);
|
|
}
|
|
else
|
|
{
|
|
SET_ZF(0);
|
|
}
|
|
}
|