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/*++
Copyright (c) 1991 Microsoft Corporation
Module Name:
pmode.c
Abstract:
This file contains 386 code for debugger extension associated with
segemented protected mode.
Author:
Dave Hastings (daveh) 3-Apr-1992
Revision History:
--*/
#include <ieuvddex.h>
#include <stdio.h>
//
// Local constants
//
#define SELECTOR_LDT 0x04
#define SELECTOR_RPL 0x03
#define SELECTOR_SYSTEM 0x10
#define SELECTOR_CODE 0x08
#define SELECTOR_CONFORMEXPAND 0x04
#define SELECTOR_READWRITE 0x02
#define SELECTOR_ACCESSED 0x01
VOID
Selp(
IN HANDLE CurrentProcess,
IN HANDLE CurrentThread,
IN LPSTR ArgumentString
)
/*++
Routine Description:
This routine dumps LDT selectors. The selectors are dumped from the
user mode Ldt, rather than the system ldt.
Arguments:
CurrentProcess -- Supplies a handle to the process to dump selectors for
CurrentThread -- Supplies a handle to the thread to dump selectors for
ArgumentString -- Supplies the arguments to the !sel command
Return Value
None.
--*/
{
BOOL Status;
ULONG BytesRead;
LONG l;
ULONG Selector, Number, ul, Index;
VDMLDT_ENTRY LdtEntries[16];
PVOID LdtAddress;
UNREFERENCED_PARAMETER(CurrentThread);
//
// Get starting selector number and number of selectors
//
if ((l = sscanf(ArgumentString, "%lx l%lx", &Selector, &Number)) < 1) {
(*Print)("Starting selector number must be specified\n");
return;
}
if (l == 1) {
Number = 16;
}
//
// Check starting selector for LDT/GDT, and remove rpl info
//
if (!(Selector & SELECTOR_LDT)) {
(*Print)("Starting selector must be an ldt selector\n");
return;
}
Selector &= ~(SELECTOR_LDT | SELECTOR_RPL);
//
// Get address of Ldt
//
LdtAddress = (PVOID)(*GetExpression)(
"ntvdm!Ldt"
);
if (!LdtAddress) {
(*Print)("Error geting Ldt address\n");
return;
}
Status = ReadProcessMem(
CurrentProcess,
LdtAddress,
&LdtAddress,
sizeof(ULONG),
&BytesRead
);
if ((!Status) || (BytesRead != sizeof(ULONG))) {
GetLastError();
(*Print)("Error reading the address of LDT table\n");
return;
}
(PUCHAR)LdtAddress += Selector;
//
// Read and dump selectors until the desired number have been done
//
while (Number > 0) {
if (Number > 16) {
ul = 16;
} else {
ul = Number;
}
Status = ReadProcessMem(
CurrentProcess,
LdtAddress,
LdtEntries,
ul * sizeof(VDMLDT_ENTRY),
&BytesRead
);
if ((!Status) || (BytesRead != ul * sizeof(VDMLDT_ENTRY))) {
GetLastError();
(*Print)("Error reading selectors\n");
return;
}
for (Index = 0; Index < ul; Index++) {
PrintDescriptor(
CurrentProcess,
&LdtEntries[Index],
Selector + Index * sizeof(VDMLDT_ENTRY)
);
}
Number -= ul;
(PUCHAR)LdtAddress += ul * sizeof(VDMLDT_ENTRY);
Selector += ul * sizeof(VDMLDT_ENTRY);
}
}
VOID
PrintDescriptor(
IN HANDLE hProcess,
IN LPVDMLDT_ENTRY Descriptor,
IN ULONG Selector
)
/*++
Routine Description:
This routine prints out the contents of a descriptor
Arguments:
Descriptor -- Supplies a pointer to the descriptor to dump
Return Value:
None.
--*/
{
ULONG Base, Limit;
Base = (Descriptor->HighWord.Bytes.BaseHi << 24)
+ (Descriptor->HighWord.Bytes.BaseMid << 16)
+ (Descriptor->BaseLow);
Limit = (Descriptor->HighWord.Bits.LimitHi << 16)
+ (Descriptor->LimitLow);
#ifdef i386
(*Print)("%04x Base=%08lx Limit=%08lx", Selector, Base, Limit);
#else
(*Print)("%04x Base=%08lx (%08lx) Limit=%08lx", Selector, Base, Base+GetIntelBase(hProcess), Limit);
#endif
if (Descriptor->HighWord.Bits.Granularity) {
(*Print)(" Pages ");
} else {
(*Print)(" Bytes ");
}
(*Print)("DPL=%x", Descriptor->HighWord.Bits.Dpl);
if (Descriptor->HighWord.Bits.Pres) {
(*Print)(" P ");
} else {
(*Print)(" NP ");
}
if (!(Descriptor->HighWord.Bits.Type & SELECTOR_SYSTEM)) {
(*Print)("System");
} else {
if (Descriptor->HighWord.Bits.Type & SELECTOR_CODE) {
(*Print)("Code ");
if (Descriptor->HighWord.Bits.Type & SELECTOR_CONFORMEXPAND) {
(*Print)("C");
} else {
(*Print)(" ");
}
if (Descriptor->HighWord.Bits.Type & SELECTOR_READWRITE) {
(*Print)("R");
} else {
(*Print)(" ");
}
} else {
(*Print)("Data ");
if (Descriptor->HighWord.Bits.Type & SELECTOR_CONFORMEXPAND) {
(*Print)("E");
} else {
(*Print)(" ");
}
if (Descriptor->HighWord.Bits.Type & SELECTOR_READWRITE) {
(*Print)("W");
} else {
(*Print)(" ");
}
}
if (Descriptor->HighWord.Bits.Type & SELECTOR_ACCESSED) {
(*Print)(" A");
} else {
(*Print)(" ");
}
if (Descriptor->HighWord.Bits.Default_Big) {
(*Print)(" Big");
}
}
(*Print)("\n");
}
ULONG GetIntelBase(
HANDLE hCurrentProcess
)
{
#ifndef i386
ULONG IntelBase;
BOOL b;
IntelBase = (ULONG)(*GetExpression)("ntvdm!Start_of_M_area");
if ( IntelBase ) {
b = ReadProcessMem( hCurrentProcess,
(LPVOID) IntelBase, &IntelBase,
sizeof(ULONG), NULL );
if ( !b ) {
(*Print)("Could not read symbol 'ntvdm!Start_of_M_area\n");
return(0);
}
} else {
(*Print)("Could not find the symbol 'ntvdm!Start_of_M_area'\n");
}
return(IntelBase);
#else
return(0);
#endif
}
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