qsfile.cpp

这个是串口驱动程序开发包

/*++

Abstract:

    This module contains the code that is very specific to query/set file
    operations in the serial driver.

--*/

#include "precomp.h"


NTSTATUS
KdSerialDevice::DispatchQueryInformation(IN KdIrp &Irp)

/*++

Routine Description:

    This routine is used to query the end of file information on
    the opened serial port.  Any other file information request
    is returned with an invalid parameter.

    This routine always returns an end of file of 0.

Arguments:

    Irp - Pointer to the IRP for the current request

Return Value:

    The function value is the final status of the call

--*/
{
    // The status that gets returned to the caller and
    // set in the Irp.
    NTSTATUS Status;

    DebugDump(DBG_DIAG6, ("Dispatch entry for: %x\n",Irp) );
    if (CompleteIfError(Irp) != STATUS_SUCCESS) 
        return STATUS_CANCELLED;

    Irp.Information() = 0L;
    Status = STATUS_SUCCESS;
    if (Irp.QueryFileInformationClass()==FileStandardInformation) 
    {
        PFILE_STANDARD_INFORMATION Buf = (PFILE_STANDARD_INFORMATION)Irp.SystemBuffer();

        Buf->AllocationSize.QuadPart = 0;
        Buf->EndOfFile = Buf->AllocationSize;
        Buf->NumberOfLinks = 0;
        Buf->DeletePending = FALSE;
        Buf->Directory = FALSE;
        Irp.Information() = sizeof(FILE_STANDARD_INFORMATION);
    } 
    else if (Irp.QueryFileInformationClass()==FilePositionInformation) 
    {
        ((PFILE_POSITION_INFORMATION)Irp.SystemBuffer())->
            CurrentByteOffset.QuadPart = 0;
        Irp.Information() = sizeof(FILE_POSITION_INFORMATION);
    } 
    else 
        Status = STATUS_INVALID_PARAMETER;

    DebugDump(DBG_DIAG6, ("Complete Irp: %x\n",Irp) );
    Irp.Complete();

    return Status;
}

NTSTATUS KdSerialDevice::DispatchSetInformation(IN KdIrp &Irp)

/*++

Routine Description:

    This routine is used to set the end of file information on
    the opened parallel port.  Any other file information request
    is returned with an invalid parameter.

    This routine always ignores the actual end of file since
    the query information code always returns an end of file of 0.

Arguments:

    Irp - Pointer to the IRP for the current request

Return Value:

The function value is the final status of the call

--*/

{
    // The status that gets returned to the caller and
    // set in the Irp.
    NTSTATUS Status;

    DebugDump(DBG_DIAG6, ("Dispatch entry for: %x\n",Irp) );
    if (CompleteIfError(Irp) != STATUS_SUCCESS)
        return STATUS_CANCELLED;

    Irp.Information() = 0L;
    if (Irp.SetFileInformationClass()==FileEndOfFileInformation ||
        Irp.SetFileInformationClass()==FileAllocationInformation ) 
    {
        Status = STATUS_SUCCESS;
    } 
    else 
        Status = STATUS_INVALID_PARAMETER;

    Irp.Status() = Status;

    DebugDump(DBG_DIAG6, ("Complete Irp: %x\n",Irp) );
    Irp.Complete();

    return Status;
}