fileinfo.c

winddk src目录下的文件系统驱动源码压缩!

    //  Extract the data and fill in the non zero fields of the output
    //  buffer
    //

    if (Fcb->Header.NodeTypeCode == FAT_NTC_ROOT_DCB) {

        //
        //  We have to munge a lie on the fly.  Every time we have to
        //  use 1/1/80 we need to convert to GMT since the TZ may have
        //  changed on us.
        //

        ExLocalTimeToSystemTime( &FatJanOne1980,
                                 &Buffer->LastWriteTime );
        Buffer->CreationTime = Buffer->LastAccessTime = Buffer->LastWriteTime;

    } else {

        Buffer->LastWriteTime = Fcb->LastWriteTime;
        Buffer->CreationTime = Fcb->CreationTime;
        Buffer->LastAccessTime = Fcb->LastAccessTime;
    }

    Buffer->FileAttributes = Fcb->DirentFatFlags;

    //
    //  If the temporary flag is set, then set it in the buffer.
    //

    if (FlagOn( Fcb->FcbState, FCB_STATE_TEMPORARY )) {

        SetFlag( Buffer->FileAttributes, FILE_ATTRIBUTE_TEMPORARY );
    }

    //
    //  If no attributes were set, set the normal bit.
    //

    if (Buffer->FileAttributes == 0) {

        Buffer->FileAttributes = FILE_ATTRIBUTE_NORMAL;
    }

    //
    //  Update the length and status output variables
    //

    *Length -= sizeof( FILE_BASIC_INFORMATION );

    DebugTrace( 0, Dbg, "*Length = %08lx\n", *Length);

    DebugTrace(-1, Dbg, "FatQueryBasicInfo -> VOID\n", 0);

    return;
}


//
//  Internal Support Routine
//

VOID
FatQueryStandardInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PFCB Fcb,
    IN OUT PFILE_STANDARD_INFORMATION Buffer,
    IN OUT PLONG Length
    )

/*++

Routine Description:

    This routine performs the query standard information function for fat.

Arguments:

    Fcb - Supplies the Fcb being queried, it has been verified

    Buffer - Supplies a pointer to the buffer where the information is to
        be returned

    Length - Supplies the length of the buffer in bytes, and receives the
        remaining bytes free in the buffer upon return.

Return Value:

    None

--*/

{
    DebugTrace(+1, Dbg, "FatQueryStandardInfo...\n", 0);

    //
    //  Zero out the output buffer, and fill in the number of links
    //  and the delete pending flag.
    //

    RtlZeroMemory( Buffer, sizeof(FILE_STANDARD_INFORMATION) );

    Buffer->NumberOfLinks = 1;
    Buffer->DeletePending = BooleanFlagOn( Fcb->FcbState, FCB_STATE_DELETE_ON_CLOSE );

    //
    //  Case on whether this is a file or a directory, and extract
    //  the information and fill in the fcb/dcb specific parts
    //  of the output buffer
    //

    if (NodeType(Fcb) == FAT_NTC_FCB) {

        if (Fcb->Header.AllocationSize.QuadPart == FCB_LOOKUP_ALLOCATIONSIZE_HINT) {

            FatLookupFileAllocationSize( IrpContext, Fcb );
        }

        Buffer->AllocationSize = Fcb->Header.AllocationSize;
        Buffer->EndOfFile = Fcb->Header.FileSize;

        Buffer->Directory = FALSE;

    } else {

        Buffer->Directory = TRUE;
    }

    //
    //  Update the length and status output variables
    //

    *Length -= sizeof( FILE_STANDARD_INFORMATION );

    DebugTrace( 0, Dbg, "*Length = %08lx\n", *Length);

    DebugTrace(-1, Dbg, "FatQueryStandardInfo -> VOID\n", 0);

    return;
}


//
//  Internal Support Routine
//

VOID
FatQueryInternalInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PFCB Fcb,
    IN OUT PFILE_INTERNAL_INFORMATION Buffer,
    IN OUT PLONG Length
    )

/*++

Routine Description:

    This routine performs the query internal information function for fat.

Arguments:

    Fcb - Supplies the Fcb being queried, it has been verified

    Buffer - Supplies a pointer to the buffer where the information is to
        be returned

    Length - Supplies the length of the buffer in bytes, and receives the
        remaining bytes free in the buffer upon return.

Return Value:

    None

--*/

{
    DebugTrace(+1, Dbg, "FatQueryInternalInfo...\n", 0);

    try {

        Buffer->IndexNumber.QuadPart = FatGenerateFileIdFromFcb( Fcb );

        //
        //  Update the length and status output variables
        //

        *Length -= sizeof( FILE_INTERNAL_INFORMATION );

    } finally {

        DebugUnwind( FatQueryInternalInfo );

        DebugTrace( 0, Dbg, "*Length = %08lx\n", *Length);

        DebugTrace(-1, Dbg, "FatQueryInternalInfo -> VOID\n", 0);
    }

    return;
}


//
//  Internal Support Routine
//

VOID
FatQueryEaInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PFCB Fcb,
    IN OUT PFILE_EA_INFORMATION Buffer,
    IN OUT PLONG Length
    )

/*++

Routine Description:

    This routine performs the query Ea information function for fat.

Arguments:

    Fcb - Supplies the Fcb being queried, it has been verified

    Buffer - Supplies a pointer to the buffer where the information is to
        be returned

    Length - Supplies the length of the buffer in bytes, and receives the
        remaining bytes free in the buffer upon return.

Return Value:

    None

--*/

{
    PBCB Bcb;

    DebugTrace(+1, Dbg, "FatQueryEaInfo...\n", 0);

    Bcb = NULL;

    try {

        //
        //  Zero out the output buffer
        //

        RtlZeroMemory( Buffer, sizeof(FILE_EA_INFORMATION) );

#if 0
        //
        //  The Root dcb does not have any EAs so don't look for any.  Fat32
        //  doesn't have any, either.
        //

        if ( NodeType( Fcb ) != FAT_NTC_ROOT_DCB &&
             !FatIsFat32( Fcb->Vcb )) {

            PDIRENT Dirent;

            //
            //  Try to get the dirent for this file.
            //

            FatGetDirentFromFcbOrDcb( IrpContext,
                                      Fcb,
                                      &Dirent,
                                      &Bcb );

            if (Dirent != NULL) {

                //
                //  Get a the size needed to store the full eas for the file.
                //

                FatGetEaLength( IrpContext,
                                Fcb->Vcb,
                                Dirent,
                                &Buffer->EaSize );
            }
        }
#endif

        //
        //  Update the length and status output variables
        //

        *Length -= sizeof( FILE_EA_INFORMATION );

    } finally {

        DebugUnwind( FatQueryEaInfo );

        //
        //  Unpin the dirent if pinned.
        //

        FatUnpinBcb( IrpContext, Bcb );

        DebugTrace( 0, Dbg, "*Length = %08lx\n", *Length);

        DebugTrace(-1, Dbg, "FatQueryEaInfo -> VOID\n", 0);
    }
}


//
//  Internal Support Routine
//

VOID
FatQueryPositionInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PFILE_OBJECT FileObject,
    IN OUT PFILE_POSITION_INFORMATION Buffer,
    IN OUT PLONG Length
    )

/*++

Routine Description:

    This routine performs the query position information function for fat.

Arguments:

    FileObject - Supplies the File object being queried

    Buffer - Supplies a pointer to the buffer where the information is to
        be returned

    Length - Supplies the length of the buffer in bytes, and receives the
        remaining bytes free in the buffer upon return.

Return Value:

    None

--*/

{
    DebugTrace(+1, Dbg, "FatQueryPositionInfo...\n", 0);

    //
    //  Get the current position found in the file object.
    //

    Buffer->CurrentByteOffset = FileObject->CurrentByteOffset;

    //
    //  Update the length and status output variables
    //

    *Length -= sizeof( FILE_POSITION_INFORMATION );

    DebugTrace( 0, Dbg, "*Length = %08lx\n", *Length);

    DebugTrace(-1, Dbg, "FatQueryPositionInfo -> VOID\n", 0);

    UNREFERENCED_PARAMETER( IrpContext );

    return;
}


//
//  Internal Support Routine
//

VOID
FatQueryNameInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PFCB Fcb,
    IN PCCB Ccb,
    IN OUT PFILE_NAME_INFORMATION Buffer,
    IN OUT PLONG Length
    )

/*++

Routine Description:

    This routine performs the query name information function for fat.

Arguments:

    Fcb - Supplies the Fcb being queried, it has been verified

    Ccb - Supplies the Ccb for the context of the user open

    Buffer - Supplies a pointer to the buffer where the information is to
        be returned

    Length - Supplies the length of the buffer in bytes, and receives the
        remaining bytes free in the buffer upon return.

Return Value:

    None

--*/

{
    ULONG BytesToCopy;
    LONG TrimLength;
    BOOLEAN Overflow = FALSE;

    DebugTrace(+1, Dbg, "FatQueryNameInfo...\n", 0);

    //
    //  Convert the name to UNICODE
    //

    *Length -= FIELD_OFFSET(FILE_NAME_INFORMATION, FileName[0]);

    //
    //  Use the full filename to build the path up.  If we wanted to be
    //  slick in the future, we'd just build the path directly into the
    //  return buffer and avoid constructing the full filename, but since
    //  the full filename winds up being required so often lets not
    //  over optimize this case yet.
    //

    if (Fcb->FullFileName.Buffer == NULL) {

        FatSetFullFileNameInFcb( IrpContext, Fcb );
    }

    //
    //  Here is where it gets a smidge tricky.  FinalNameLength is the length
    //  of the LFN element if it exists, and since the long name is always used
    //  to build FullFileName, we have two cases:
    //
    //  1) short name: use FinalNameLength to tear off the path from FullFileName
    //      and append the UNICODE converted short name.
    //  2) long name: just use FullFileName
    //
    //  We bias to the name the user thinks they opened by.  This winds
    //  up fixing some oddball tunneling cases where intermediate filters
    //  translate operations like delete into renames - this lets them
    //  do the operation in the context of the name the user was using.
    //
    //  It also matches what NTFS does, and so we have the definition of
    //  correct behavior.
    //

    //
    //
    //  Assume there is no long name and we are just going to use
    //  FullFileName.
    //

    TrimLength = 0;

    //
    //  If a LongName exists and the original open was by the short name
    //  then set TrimLength to point to the place where the short name goes.
    //
    //
    //  Note: The Ccb can be NULL.  The lazy writer calls to get the name of
    //  a DirectoryOpen FILE_OBJECT that it wants to display in the lost
    //  delayed write popup.  Handle this case by just using the FileFullName.
    //

    if (Fcb->LongName.Unicode.Name.Unicode.Buffer != NULL) {

        if ((Ccb != NULL) && FlagOn(Ccb->Flags, CCB_FLAG_OPENED_BY_SHORTNAME)) {

            TrimLength = Fcb->FinalNameLength;
        }
    }

    if (*Length < Fcb->FullFileName.Length - TrimLength) {

        BytesToCopy = *Length;
        Overflow = TRUE;

    } else {

        BytesToCopy = Fcb->FullFileName.Length - TrimLength;
        *Length -= BytesToCopy;
    }

    RtlCopyMemory( &Buffer->FileName[0],
                   Fcb->FullFileName.Buffer,
                   BytesToCopy );

    //
    //  Note that this is just the amount of name we've copied so far.  It'll
    //  either be all of it (long) or the path element including the \ (short).
    //

    Buffer->FileNameLength = Fcb->FullFileName.Length - TrimLength;

    //
    //  If we trimmed off the name element, this is the short name case.  Pick