/*++
Copyright (c) 1985 - 1999, Microsoft Corporation

Module Name:
    NtHard.c
--*/

#include "precomp.h"
#pragma hdrstop

#if defined(i386)
#define REGISTRY_HARDWARE_DESCRIPTION         TEXT("\\Registry\\Machine\\Hardware\\DESCRIPTION\\System")
#define REGISTRY_MACHINE_IDENTIFIER           TEXT("Identifier")
#define FUJITSU_FMR_NAME    TEXT("FUJITSU FMR-")
#define NEC_PC98_NAME       TEXT("NEC PC-98")
#define KEY_WORK_AREA ((sizeof(KEY_VALUE_FULL_INFORMATION) + sizeof(ULONG)) + 256)


NTSTATUS NtGetMachineIdentifierValue(IN OUT PULONG Value)
/*++
Routine Description:
    Given a unicode value name this routine will go into the registry location for the machine identifier information and get the value.
Arguments:
    ValueName - the unicode name for the registry value located in the identifier location of the registry.
    Value   - a pointer to the ULONG for the result.
Return Value:

    NTSTATUS

    If STATUS_SUCCESSFUL is returned, the location *Value will be updated with the DWORD value from the registry.
    If any failing status is returned, this value is untouched.
--*/
{
    HANDLE Handle;
    NTSTATUS Status;
    ULONG RequestLength;
    ULONG ResultLength;
    UCHAR Buffer[KEY_WORK_AREA];
    UNICODE_STRING KeyName;
    UNICODE_STRING ValueName;
    OBJECT_ATTRIBUTES ObjectAttributes;
    PKEY_VALUE_FULL_INFORMATION KeyValueInformation;

    // Set default as PC/AT
    *Value = MACHINEID_MS_PCAT;

    KeyName.Buffer = REGISTRY_HARDWARE_DESCRIPTION;
    KeyName.Length = sizeof(REGISTRY_HARDWARE_DESCRIPTION) - sizeof(WCHAR);
    KeyName.MaximumLength = sizeof(REGISTRY_HARDWARE_DESCRIPTION);
    InitializeObjectAttributes(&ObjectAttributes, &KeyName, OBJ_CASE_INSENSITIVE, NULL, NULL);
    Status = NtOpenKey(&Handle, KEY_READ, &ObjectAttributes);
    if (!NT_SUCCESS(Status)) {
        return Status;
    }

    ValueName.Buffer = REGISTRY_MACHINE_IDENTIFIER;
    ValueName.Length = sizeof(REGISTRY_MACHINE_IDENTIFIER) - sizeof(WCHAR);
    ValueName.MaximumLength = sizeof(REGISTRY_MACHINE_IDENTIFIER);
    RequestLength = KEY_WORK_AREA;
    KeyValueInformation = (PKEY_VALUE_FULL_INFORMATION)Buffer;
    Status = NtQueryValueKey(Handle, &ValueName, KeyValueFullInformation, KeyValueInformation, RequestLength, &ResultLength);
    ASSERT( Status != STATUS_BUFFER_OVERFLOW );
    NtClose(Handle);
    if (NT_SUCCESS(Status)) {
        if (KeyValueInformation->DataLength != 0) {
            PWCHAR DataPtr;
            UNICODE_STRING DetectedString, TargetString1, TargetString2;

            DataPtr = (PWCHAR) ((PUCHAR)KeyValueInformation + KeyValueInformation->DataOffset);// Return contents to the caller.

            // Initialize strings.
            RtlInitUnicodeString( &DetectedString, DataPtr );
            RtlInitUnicodeString( &TargetString1, FUJITSU_FMR_NAME );
            RtlInitUnicodeString( &TargetString2, NEC_PC98_NAME );

            // Check the hardware platform
            if (RtlPrefixUnicodeString( &TargetString1 , &DetectedString , TRUE)) {
                *Value = MACHINEID_FUJITSU_FMR;// Fujitsu FMR Series.
            } else if (RtlPrefixUnicodeString( &TargetString2 , &DetectedString , TRUE)) {
                *Value = MACHINEID_NEC_PC98; // NEC PC-9800 Seriss
            } else {
                *Value = MACHINEID_MS_PCAT;// Standard PC/AT comapatibles
            }
        } else {
            // Treat as if no value was found
            Status = STATUS_OBJECT_NAME_NOT_FOUND;
        }
    }

    return Status;
}
#endif // defined(i386)