Sample Code
Windows Driver Samples/ fastfat File System Driver/ C++/ dirctrl.c/
/*++
Copyright (c) 1989-2000 Microsoft Corporation
Module Name:
DirCtrl.c
Abstract:
This module implements the File Directory Control routines for Fat called
by the dispatch driver.
--*/
#include "FatProcs.h"
//
// The Bug check file id for this module
//
#define BugCheckFileId (FAT_BUG_CHECK_DIRCTRL)
//
// The local debug trace level
//
#define Dbg (DEBUG_TRACE_DIRCTRL)
WCHAR Fat8QMdot3QM[12] = { DOS_QM, DOS_QM, DOS_QM, DOS_QM, DOS_QM, DOS_QM, DOS_QM, DOS_QM,
L'.', DOS_QM, DOS_QM, DOS_QM};
//
// Local procedure prototypes
//
_Requires_lock_held_(_Global_critical_region_)
NTSTATUS
FatQueryDirectory (
IN PIRP_CONTEXT IrpContext,
IN PIRP Irp
);
VOID
FatGetDirTimes(
PIRP_CONTEXT IrpContext,
PDIRENT Dirent,
PFILE_DIRECTORY_INFORMATION DirInfo
);
_Requires_lock_held_(_Global_critical_region_)
NTSTATUS
FatNotifyChangeDirectory (
IN PIRP_CONTEXT IrpContext,
IN PIRP Irp
);
#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE, FatCommonDirectoryControl)
#pragma alloc_text(PAGE, FatFsdDirectoryControl)
#pragma alloc_text(PAGE, FatNotifyChangeDirectory)
#pragma alloc_text(PAGE, FatQueryDirectory)
#pragma alloc_text(PAGE, FatGetDirTimes)
#endif
_Function_class_(IRP_MJ_DIRECTORY_CONTROL)
_Function_class_(DRIVER_DISPATCH)
NTSTATUS
FatFsdDirectoryControl (
_In_ PVOLUME_DEVICE_OBJECT VolumeDeviceObject,
_Inout_ PIRP Irp
)
/*++
Routine Description:
This routine implements the FSD part of directory control
Arguments:
VolumeDeviceObject - Supplies the volume device object where the
file exists
Irp - Supplies the Irp being processed
Return Value:
NTSTATUS - The FSD status for the IRP
--*/
{
NTSTATUS Status;
PIRP_CONTEXT IrpContext = NULL;
BOOLEAN TopLevel;
PAGED_CODE();
DebugTrace(+1, Dbg, "FatFsdDirectoryControl\n", 0);
//
// Call the common directory Control routine, with blocking allowed if
// synchronous
//
FsRtlEnterFileSystem();
TopLevel = FatIsIrpTopLevel( Irp );
try {
IrpContext = FatCreateIrpContext( Irp, CanFsdWait( Irp ) );
Status = FatCommonDirectoryControl( IrpContext, Irp );
} except(FatExceptionFilter( IrpContext, GetExceptionInformation() )) {
//
// We had some trouble trying to perform the requested
// operation, so we'll abort the I/O request with
// the error status that we get back from the
// execption code
//
Status = FatProcessException( IrpContext, Irp, GetExceptionCode() );
}
if (TopLevel) { IoSetTopLevelIrp( NULL ); }
FsRtlExitFileSystem();
//
// And return to our caller
//
DebugTrace(-1, Dbg, "FatFsdDirectoryControl -> %08lx\n", Status);
UNREFERENCED_PARAMETER( VolumeDeviceObject );
return Status;
}
_Requires_lock_held_(_Global_critical_region_)
NTSTATUS
FatCommonDirectoryControl (
IN PIRP_CONTEXT IrpContext,
IN PIRP Irp
)
/*++
Routine Description:
This is the common routine for doing directory control operations called
by both the fsd and fsp threads
Arguments:
Irp - Supplies the Irp to process
Return Value:
NTSTATUS - The return status for the operation
--*/
{
NTSTATUS Status;
PIO_STACK_LOCATION IrpSp;
PAGED_CODE();
//
// Get a pointer to the current Irp stack location
//
IrpSp = IoGetCurrentIrpStackLocation( Irp );
DebugTrace(+1, Dbg, "FatCommonDirectoryControl\n", 0);
DebugTrace( 0, Dbg, "Irp = %08lx\n", Irp );
DebugTrace( 0, Dbg, "MinorFunction = %08lx\n", IrpSp->MinorFunction );
//
// We know this is a directory control so we'll case on the
// minor function, and call a internal worker routine to complete
// the irp.
//
switch ( IrpSp->MinorFunction ) {
case IRP_MN_QUERY_DIRECTORY:
Status = FatQueryDirectory( IrpContext, Irp );
break;
case IRP_MN_NOTIFY_CHANGE_DIRECTORY:
Status = FatNotifyChangeDirectory( IrpContext, Irp );
break;
default:
DebugTrace(0, Dbg, "Invalid Directory Control Minor Function %08lx\n", IrpSp->MinorFunction);
FatCompleteRequest( IrpContext, Irp, STATUS_INVALID_DEVICE_REQUEST );
Status = STATUS_INVALID_DEVICE_REQUEST;
break;
}
DebugTrace(-1, Dbg, "FatCommonDirectoryControl -> %08lx\n", Status);
return Status;
}
//
// Local Support Routine
//
_Requires_lock_held_(_Global_critical_region_)
NTSTATUS
FatQueryDirectory (
IN PIRP_CONTEXT IrpContext,
IN PIRP Irp
)
/*++
Routine Description:
This routine performs the query directory operation. It is responsible
for either completing of enqueuing the input Irp.
Arguments:
Irp - Supplies the Irp to process
Return Value:
NTSTATUS - The return status for the operation
--*/
{
NTSTATUS Status;
PIO_STACK_LOCATION IrpSp;
PVCB Vcb;
PDCB Dcb;
PCCB Ccb;
PBCB Bcb;
ULONG i;
PUCHAR Buffer;
CLONG UserBufferLength;
PUNICODE_STRING UniArgFileName;
WCHAR LongFileNameBuffer[ FAT_CREATE_INITIAL_NAME_BUF_SIZE];
UNICODE_STRING LongFileName;
FILE_INFORMATION_CLASS FileInformationClass;
ULONG FileIndex;
BOOLEAN RestartScan;
BOOLEAN ReturnSingleEntry;
BOOLEAN IndexSpecified;
BOOLEAN InitialQuery;
VBO CurrentVbo = 0;
BOOLEAN UpdateCcb;
PDIRENT Dirent;
UCHAR Fat8Dot3Buffer[12];
OEM_STRING Fat8Dot3String;
ULONG DiskAllocSize;
ULONG NextEntry;
ULONG LastEntry;
PFILE_DIRECTORY_INFORMATION DirInfo;
PFILE_FULL_DIR_INFORMATION FullDirInfo;
PFILE_BOTH_DIR_INFORMATION BothDirInfo;
PFILE_ID_FULL_DIR_INFORMATION IdFullDirInfo;
PFILE_ID_BOTH_DIR_INFORMATION IdBothDirInfo;
PFILE_NAMES_INFORMATION NamesInfo;
PAGED_CODE();
//
// Get the current Stack location
//
IrpSp = IoGetCurrentIrpStackLocation( Irp );
//
// Display the input values.
//
DebugTrace(+1, Dbg, "FatQueryDirectory...\n", 0);
DebugTrace( 0, Dbg, " Wait = %08lx\n", FlagOn(IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT));
DebugTrace( 0, Dbg, " Irp = %08lx\n", Irp);
DebugTrace( 0, Dbg, " ->Length = %08lx\n", IrpSp->Parameters.QueryDirectory.Length);
DebugTrace( 0, Dbg, " ->FileName = %08lx\n", IrpSp->Parameters.QueryDirectory.FileName);
DebugTrace( 0, Dbg, " ->FileInformationClass = %08lx\n", IrpSp->Parameters.QueryDirectory.FileInformationClass);
DebugTrace( 0, Dbg, " ->FileIndex = %08lx\n", IrpSp->Parameters.QueryDirectory.FileIndex);
DebugTrace( 0, Dbg, " ->UserBuffer = %08lx\n", Irp->AssociatedIrp.SystemBuffer);
DebugTrace( 0, Dbg, " ->RestartScan = %08lx\n", FlagOn( IrpSp->Flags, SL_RESTART_SCAN ));
DebugTrace( 0, Dbg, " ->ReturnSingleEntry = %08lx\n", FlagOn( IrpSp->Flags, SL_RETURN_SINGLE_ENTRY ));
DebugTrace( 0, Dbg, " ->IndexSpecified = %08lx\n", FlagOn( IrpSp->Flags, SL_INDEX_SPECIFIED ));
//
// Reference our input parameters to make things easier
//
UserBufferLength = IrpSp->Parameters.QueryDirectory.Length;
FileInformationClass = IrpSp->Parameters.QueryDirectory.FileInformationClass;
FileIndex = IrpSp->Parameters.QueryDirectory.FileIndex;
UniArgFileName = IrpSp->Parameters.QueryDirectory.FileName;
RestartScan = BooleanFlagOn(IrpSp->Flags, SL_RESTART_SCAN);
ReturnSingleEntry = BooleanFlagOn(IrpSp->Flags, SL_RETURN_SINGLE_ENTRY);
IndexSpecified = BooleanFlagOn(IrpSp->Flags, SL_INDEX_SPECIFIED);
//
// Check on the type of open. We return invalid parameter for all
// but UserDirectoryOpens. Also check that the filename is a valid
// UNICODE string.
//
if (FatDecodeFileObject( IrpSp->FileObject,
&Vcb,
&Dcb,
&Ccb) != UserDirectoryOpen ||
(UniArgFileName &&
UniArgFileName->Length % sizeof(WCHAR))) {
FatCompleteRequest( IrpContext, Irp, STATUS_INVALID_PARAMETER );
DebugTrace(-1, Dbg, "FatQueryDirectory -> STATUS_INVALID_PARAMETER\n", 0);
return STATUS_INVALID_PARAMETER;
}
//
// Initialize the local variables.
//
Bcb = NULL;
UpdateCcb = TRUE;
Dirent = NULL;
Fat8Dot3String.MaximumLength = 12;
Fat8Dot3String.Buffer = (PCHAR)Fat8Dot3Buffer;
LongFileName.Length = 0;
LongFileName.MaximumLength = sizeof( LongFileNameBuffer);
LongFileName.Buffer = LongFileNameBuffer;
InitialQuery = (BOOLEAN)((Ccb->UnicodeQueryTemplate.Buffer == NULL) &&
!FlagOn(Ccb->Flags, CCB_FLAG_MATCH_ALL));
Status = STATUS_SUCCESS;
Irp->IoStatus.Information = 0;
DiskAllocSize = 1 << Vcb->AllocationSupport.LogOfBytesPerCluster;
//
// If this is the initial query, then grab exclusive access in
// order to update the search string in the Ccb. We may
// discover that we are not the initial query once we grab the Fcb
// and downgrade our status.
//
// If restartscan is set, we may be replacing the query template,
// so take the FCB exclusive to protect against multiple people
// changing the CCB at once.
//
if (InitialQuery || RestartScan) {
if (!FatAcquireExclusiveFcb( IrpContext, Dcb )) {
DebugTrace(0, Dbg, "FatQueryDirectory -> Enqueue to Fsp\n", 0);
Status = FatFsdPostRequest( IrpContext, Irp );
DebugTrace(-1, Dbg, "FatQueryDirectory -> %08lx\n", Status);
return Status;
}
if (!RestartScan && (Ccb->UnicodeQueryTemplate.Buffer != NULL)) {
InitialQuery = FALSE;
FatConvertToSharedFcb( IrpContext, Dcb );
}
} else {
if (!FatAcquireSharedFcb( IrpContext, Dcb )) {
DebugTrace(0, Dbg, "FatQueryDirectory -> Enqueue to Fsp\n", 0);
Status = FatFsdPostRequest( IrpContext, Irp );
DebugTrace(-1, Dbg, "FatQueryDirectory -> %08lx\n", Status);
return Status;
}
}
try {
ULONG BaseLength;
ULONG BytesConverted;
//
// If we are in the Fsp now because we had to wait earlier,
// we must map the user buffer, otherwise we can use the
// user's buffer directly.
//
Buffer = FatMapUserBuffer( IrpContext, Irp );
//
// Make sure the Dcb is still good.
//
FatVerifyFcb( IrpContext, Dcb );
//
// Determine where to start the scan. Highest priority is given
// to the file index. Lower priority is the restart flag. If
// neither of these is specified, then the Vbo offset field in the
// Ccb is used.
//
if (IndexSpecified) {
CurrentVbo = FileIndex + sizeof( DIRENT );
} else if (RestartScan) {
CurrentVbo = 0;
Ccb->OffsetToStartSearchFrom = 0;
} else {
CurrentVbo = Ccb->OffsetToStartSearchFrom;
}
//
// If this is the first try then allocate a buffer for the file
// name.
//
if (InitialQuery ||
(RestartScan && UniArgFileName != NULL && UniArgFileName->Length != 0)) {
//
// If we're restarting the scan, clear out the pattern in the Ccb and regenerate it,
//
if (RestartScan) {
if (Ccb->UnicodeQueryTemplate.Buffer) {
if (FlagOn(Ccb->Flags, CCB_FLAG_FREE_UNICODE)) {
ExFreePoolWithTag(Ccb->UnicodeQueryTemplate.Buffer, TAG_FILENAME_BUFFER);
ClearFlag(Ccb->Flags, CCB_FLAG_FREE_UNICODE);
}
Ccb->UnicodeQueryTemplate.Buffer = NULL;
Ccb->UnicodeQueryTemplate.Length = 0;
Ccb->UnicodeQueryTemplate.MaximumLength = 0;
}
if (Ccb->OemQueryTemplate.Wild.Buffer) {
if (FlagOn(Ccb->Flags, CCB_FLAG_FREE_OEM_BEST_FIT)) {
RtlFreeOemString( &Ccb->OemQueryTemplate.Wild );
ClearFlag(Ccb->Flags, CCB_FLAG_FREE_OEM_BEST_FIT);
}
Ccb->OemQueryTemplate.Wild.Buffer = NULL;
Ccb->OemQueryTemplate.Wild.Length = 0;
Ccb->OemQueryTemplate.Wild.MaximumLength = 0;
}
Ccb->ContainsWildCards = FALSE;
ClearFlag(Ccb->Flags, CCB_FLAG_MATCH_ALL);
ClearFlag(Ccb->Flags, CCB_FLAG_FREE_UNICODE);
ClearFlag(Ccb->Flags, CCB_FLAG_SKIP_SHORT_NAME_COMPARE);
ClearFlag(Ccb->Flags, CCB_FLAG_QUERY_TEMPLATE_MIXED);
}
//
// If either:
//
// - No name was specified
// - An empty name was specified
// - We received a '*'
// - The user specified the DOS equivolent of ????????.???
//
// then match all names.
//
if ((UniArgFileName == NULL) ||
(UniArgFileName->Length == 0) ||
(UniArgFileName->Buffer == NULL) ||
((UniArgFileName->Length == sizeof(WCHAR)) &&
(UniArgFileName->Buffer[0] == L'*')) ||
((UniArgFileName->Length == 12*sizeof(WCHAR)) &&
(RtlEqualMemory( UniArgFileName->Buffer,
Fat8QMdot3QM,
12*sizeof(WCHAR) )))) {
Ccb->ContainsWildCards = TRUE;
SetFlag( Ccb->Flags, CCB_FLAG_MATCH_ALL );
} else {
BOOLEAN ExtendedName = FALSE;
OEM_STRING LocalBestFit;
//
// First and formost, see if the name has wild cards.
//
Ccb->ContainsWildCards =
FsRtlDoesNameContainWildCards( UniArgFileName );
//
// Now check to see if the name contains any extended
// characters
//
for (i=0; i < UniArgFileName->Length / sizeof(WCHAR); i++) {
if (UniArgFileName->Buffer[i] >= 0x80) {
ExtendedName = TRUE;
break;
}
}
//
// OK, now do the conversions we need.
//
if (ExtendedName) {
Status = RtlUpcaseUnicodeString( &Ccb->UnicodeQueryTemplate,
UniArgFileName,
TRUE );
if (!NT_SUCCESS(Status)) {
try_return( Status );
}
SetFlag( Ccb->Flags, CCB_FLAG_FREE_UNICODE );
//
// Upcase the name and convert it to the Oem code page.
//
Status = RtlUpcaseUnicodeStringToCountedOemString( &LocalBestFit,
UniArgFileName,
TRUE );
//
// If this conversion failed for any reason other than
// an unmappable character fail the request.
//
if (!NT_SUCCESS(Status)) {
if (Status == STATUS_UNMAPPABLE_CHARACTER) {
SetFlag( Ccb->Flags, CCB_FLAG_SKIP_SHORT_NAME_COMPARE );
} else {
try_return( Status );
}
} else {
SetFlag( Ccb->Flags, CCB_FLAG_FREE_OEM_BEST_FIT );
}
} else {
PVOID Buffers;
//
// This case is optimized because I know I only have to
// worry about a-z.
//
Buffers = FsRtlAllocatePoolWithTag( PagedPool,
UniArgFileName->Length +
UniArgFileName->Length / sizeof(WCHAR),
TAG_FILENAME_BUFFER );
Ccb->UnicodeQueryTemplate.Buffer = Buffers;
Ccb->UnicodeQueryTemplate.Length = UniArgFileName->Length;
Ccb->UnicodeQueryTemplate.MaximumLength = UniArgFileName->Length;
LocalBestFit.Buffer = (PCHAR)Buffers + UniArgFileName->Length;
LocalBestFit.Length = UniArgFileName->Length / sizeof(WCHAR);
LocalBestFit.MaximumLength = LocalBestFit.Length;
SetFlag( Ccb->Flags, CCB_FLAG_FREE_UNICODE );
for (i=0; i < UniArgFileName->Length / sizeof(WCHAR); i++) {
WCHAR c = UniArgFileName->Buffer[i];
LocalBestFit.Buffer[i] = (UCHAR)
(Ccb->UnicodeQueryTemplate.Buffer[i] =
(c < 'a' ? c : c <= 'z' ? c - ('a' - 'A') : c));
}
}
//
// At this point we now have the upcased unicode name,
// and the two Oem names if they could be represented in
// this code page.
//
// Now determine if the Oem names are legal for what we
// going to try and do. Mark them as not usable is they
// are not legal. Note that we can optimize extended names
// since they are actually both the same string.
//
if (!FlagOn( Ccb->Flags, CCB_FLAG_SKIP_SHORT_NAME_COMPARE ) &&
!FatIsNameShortOemValid( IrpContext,
LocalBestFit,
Ccb->ContainsWildCards,
FALSE,
FALSE )) {
if (ExtendedName) {
RtlFreeOemString( &LocalBestFit );
ClearFlag( Ccb->Flags, CCB_FLAG_FREE_OEM_BEST_FIT );
}
SetFlag( Ccb->Flags, CCB_FLAG_SKIP_SHORT_NAME_COMPARE );
}
//
// OK, now both locals oem strings correctly reflect their
// usability. Now we want to load up the Ccb structure.
//
// Now we will branch on two paths of wheather the name
// is wild or not.
//
if (!FlagOn( Ccb->Flags, CCB_FLAG_SKIP_SHORT_NAME_COMPARE )) {
if (Ccb->ContainsWildCards) {
Ccb->OemQueryTemplate.Wild = LocalBestFit;
} else {
FatStringTo8dot3( IrpContext,
LocalBestFit,
&Ccb->OemQueryTemplate.Constant );
if (FlagOn(Ccb->Flags, CCB_FLAG_FREE_OEM_BEST_FIT)) {
RtlFreeOemString( &LocalBestFit );
ClearFlag( Ccb->Flags, CCB_FLAG_FREE_OEM_BEST_FIT );
}
}
}
}
//
// We convert to shared access.
//
FatConvertToSharedFcb( IrpContext, Dcb );
}
LastEntry = 0;
NextEntry = 0;
switch (FileInformationClass) {
case FileDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_DIRECTORY_INFORMATION,
FileName[0] );
break;
case FileFullDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_FULL_DIR_INFORMATION,
FileName[0] );
break;
case FileIdFullDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_ID_FULL_DIR_INFORMATION,
FileName[0] );
break;
case FileNamesInformation:
BaseLength = FIELD_OFFSET( FILE_NAMES_INFORMATION,
FileName[0] );
break;
case FileBothDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_BOTH_DIR_INFORMATION,
FileName[0] );
break;
case FileIdBothDirectoryInformation:
BaseLength = FIELD_OFFSET( FILE_ID_BOTH_DIR_INFORMATION,
FileName[0] );
break;
default:
try_return( Status = STATUS_INVALID_INFO_CLASS );
}
//
// At this point we are about to enter our query loop. We have
// determined the index into the directory file to begin the
// search. LastEntry and NextEntry are used to index into the user
// buffer. LastEntry is the last entry we've added, NextEntry is
// current one we're working on. If NextEntry is non-zero, then
// at least one entry was added.
//
while ( TRUE ) {
VBO NextVbo;
ULONG FileNameLength;
ULONG BytesRemainingInBuffer;
BOOLEAN FileNameDos;
DebugTrace(0, Dbg, "FatQueryDirectory -> Top of loop\n", 0);
//
// If the user had requested only a single match and we have
// returned that, then we stop at this point.
//
if (ReturnSingleEntry && NextEntry != 0) {
try_return( Status );
}
//
// We call FatLocateDirent to lock down the next matching dirent.
//
FatLocateDirent( IrpContext,
Dcb,
Ccb,
CurrentVbo,
&Dirent,
&Bcb,
&NextVbo,
&FileNameDos,
&LongFileName);
//
// If we didn't receive a dirent, then we are at the end of the
// directory. If we have returned any files, we exit with
// success, otherwise we return STATUS_NO_MORE_FILES.
//
if (!Dirent) {
DebugTrace(0, Dbg, "FatQueryDirectory -> No dirent\n", 0);
if (NextEntry == 0) {
UpdateCcb = FALSE;
if (InitialQuery) {
Status = STATUS_NO_SUCH_FILE;
} else {
Status = STATUS_NO_MORE_FILES;
}
}
try_return( Status );
}
//
// Protect access to the user buffer with an exception handler.
// Since (at our request) IO doesn't buffer these requests, we have
// to guard against a user messing with the page protection and other
// such trickery.
//
try {
if (LongFileName.Length == 0) {
//
// Now we have an entry to return to our caller. We'll convert
// the name from the form in the dirent to a <name>.<ext> form.
// We'll case on the type of information requested and fill up
// the user buffer if everything fits.
//
Fat8dot3ToString( IrpContext, Dirent, TRUE, &Fat8Dot3String );
//
// Determine the UNICODE length of the file name.
//
FileNameLength = RtlOemStringToCountedUnicodeSize(&Fat8Dot3String);
//
// Here are the rules concerning filling up the buffer:
//
// 1. The Io system garentees that there will always be
// enough room for at least one base record.
//
// 2. If the full first record (including file name) cannot
// fit, as much of the name as possible is copied and
// STATUS_BUFFER_OVERFLOW is returned.
//
// 3. If a subsequent record cannot completely fit into the
// buffer, none of it (as in 0 bytes) is copied, and
// STATUS_SUCCESS is returned. A subsequent query will
// pick up with this record.
//
BytesRemainingInBuffer = UserBufferLength - NextEntry;
if ( (NextEntry != 0) &&
( (BaseLength + FileNameLength > BytesRemainingInBuffer) ||
(UserBufferLength < NextEntry) ) ) {
DebugTrace(0, Dbg, "Next entry won't fit\n", 0);
try_return( Status = STATUS_SUCCESS );
}
NT_ASSERT( BytesRemainingInBuffer >= BaseLength );
//
// Zero the base part of the structure.
//
RtlZeroMemory( &Buffer[NextEntry], BaseLength );
switch ( FileInformationClass ) {
//
// Now fill the base parts of the strucure that are applicable.
//
case FileBothDirectoryInformation:
case FileFullDirectoryInformation:
case FileIdBothDirectoryInformation:
case FileIdFullDirectoryInformation:
DebugTrace(0, Dbg, "FatQueryDirectory -> Getting file full directory information\n", 0);
//
// Get the Ea file length.
//
FullDirInfo = (PFILE_FULL_DIR_INFORMATION)&Buffer[NextEntry];
//
// If the EAs are corrupt, ignore the error. We don't want
// to abort the directory query.
//
try {
FatGetEaLength( IrpContext,
Vcb,
Dirent,
&FullDirInfo->EaSize );
} except(EXCEPTION_EXECUTE_HANDLER) {
FatResetExceptionState( IrpContext );
FullDirInfo->EaSize = 0;
}
case FileDirectoryInformation:
DirInfo = (PFILE_DIRECTORY_INFORMATION)&Buffer[NextEntry];
FatGetDirTimes( IrpContext, Dirent, DirInfo );
DirInfo->EndOfFile.QuadPart = Dirent->FileSize;
if (!FlagOn( Dirent->Attributes, FAT_DIRENT_ATTR_DIRECTORY )) {
DirInfo->AllocationSize.QuadPart =
(((Dirent->FileSize + DiskAllocSize - 1) / DiskAllocSize) *
DiskAllocSize );
}
DirInfo->FileAttributes = Dirent->Attributes != 0 ?
Dirent->Attributes :
FILE_ATTRIBUTE_NORMAL;
DirInfo->FileIndex = NextVbo;
DirInfo->FileNameLength = FileNameLength;
DebugTrace(0, Dbg, "FatQueryDirectory -> Name = \"%Z\"\n", &Fat8Dot3String);
break;
case FileNamesInformation:
DebugTrace(0, Dbg, "FatQueryDirectory -> Getting file names information\n", 0);
NamesInfo = (PFILE_NAMES_INFORMATION)&Buffer[NextEntry];
NamesInfo->FileIndex = NextVbo;
NamesInfo->FileNameLength = FileNameLength;
DebugTrace(0, Dbg, "FatQueryDirectory -> Name = \"%Z\"\n", &Fat8Dot3String );
break;
default:
#pragma prefast( suppress:28159, "things are seriously wrong if we get here" )
FatBugCheck( FileInformationClass, 0, 0 );
}
BytesConverted = 0;
Status = RtlOemToUnicodeN( (PWCH)&Buffer[NextEntry + BaseLength],
BytesRemainingInBuffer - BaseLength,
&BytesConverted,
Fat8Dot3String.Buffer,
Fat8Dot3String.Length );
//
// Check for the case that a single entry doesn't fit.
// This should only get this far on the first entry
//
if (BytesConverted < FileNameLength) {
NT_ASSERT( NextEntry == 0 );
Status = STATUS_BUFFER_OVERFLOW;
}
//
// Set up the previous next entry offset
//
*((PULONG)(&Buffer[LastEntry])) = NextEntry - LastEntry;
//
// And indicate how much of the user buffer we have currently
// used up. We must compute this value before we long align
// ourselves for the next entry
//
Irp->IoStatus.Information = QuadAlign( Irp->IoStatus.Information ) +
BaseLength + BytesConverted;
//
// If something happened with the conversion, bail here.
//
if ( !NT_SUCCESS( Status ) ) {
try_return( NOTHING );
}
} else {
ULONG ShortNameLength;
FileNameLength = LongFileName.Length;
//
// Here are the rules concerning filling up the buffer:
//
// 1. The Io system garentees that there will always be
// enough room for at least one base record.
//
// 2. If the full first record (including file name) cannot
// fit, as much of the name as possible is copied and
// STATUS_BUFFER_OVERFLOW is returned.
//
// 3. If a subsequent record cannot completely fit into the
// buffer, none of it (as in 0 bytes) is copied, and
// STATUS_SUCCESS is returned. A subsequent query will
// pick up with this record.
//
BytesRemainingInBuffer = UserBufferLength - NextEntry;
if ( (NextEntry != 0) &&
( (BaseLength + FileNameLength > BytesRemainingInBuffer) ||
(UserBufferLength < NextEntry) ) ) {
DebugTrace(0, Dbg, "Next entry won't fit\n", 0);
try_return( Status = STATUS_SUCCESS );
}
NT_ASSERT( BytesRemainingInBuffer >= BaseLength );
//
// Zero the base part of the structure.
//
RtlZeroMemory( &Buffer[NextEntry], BaseLength );
switch ( FileInformationClass ) {
//
// Now fill the base parts of the strucure that are applicable.
//
case FileBothDirectoryInformation:
case FileIdBothDirectoryInformation:
BothDirInfo = (PFILE_BOTH_DIR_INFORMATION)&Buffer[NextEntry];
//
// Now we have an entry to return to our caller. We'll convert
// the name from the form in the dirent to a <name>.<ext> form.
// We'll case on the type of information requested and fill up
// the user buffer if everything fits.
//
Fat8dot3ToString( IrpContext, Dirent, FALSE, &Fat8Dot3String );
NT_ASSERT( Fat8Dot3String.Length <= 12 );
Status = RtlOemToUnicodeN( &BothDirInfo->ShortName[0],
12*sizeof(WCHAR),
&ShortNameLength,
Fat8Dot3String.Buffer,
Fat8Dot3String.Length );
NT_ASSERT( Status != STATUS_BUFFER_OVERFLOW );
NT_ASSERT( ShortNameLength <= 12*sizeof(WCHAR) );
//
// Copy the length into the dirinfo structure. Note
// that the LHS below is a USHORT, so it can not
// be specificed as the OUT parameter above.
//
BothDirInfo->ShortNameLength = (UCHAR)ShortNameLength;
//
// If something happened with the conversion, bail here.
//
if ( !NT_SUCCESS( Status ) ) {
try_return( NOTHING );
}
case FileFullDirectoryInformation:
case FileIdFullDirectoryInformation:
DebugTrace(0, Dbg, "FatQueryDirectory -> Getting file full directory information\n", 0);
//
// Get the Ea file length.
//
FullDirInfo = (PFILE_FULL_DIR_INFORMATION)&Buffer[NextEntry];
//
// If the EAs are corrupt, ignore the error. We don't want
// to abort the directory query.
//
try {
FatGetEaLength( IrpContext,
Vcb,
Dirent,
&FullDirInfo->EaSize );
} except(EXCEPTION_EXECUTE_HANDLER) {
FatResetExceptionState( IrpContext );
FullDirInfo->EaSize = 0;
}
case FileDirectoryInformation:
DirInfo = (PFILE_DIRECTORY_INFORMATION)&Buffer[NextEntry];
FatGetDirTimes( IrpContext, Dirent, DirInfo );
DirInfo->EndOfFile.QuadPart = Dirent->FileSize;
if (!FlagOn( Dirent->Attributes, FAT_DIRENT_ATTR_DIRECTORY )) {
DirInfo->AllocationSize.QuadPart = (
(( Dirent->FileSize
+ DiskAllocSize - 1 )
/ DiskAllocSize )
* DiskAllocSize );
}
DirInfo->FileAttributes = Dirent->Attributes != 0 ?
Dirent->Attributes :
FILE_ATTRIBUTE_NORMAL;
DirInfo->FileIndex = NextVbo;
DirInfo->FileNameLength = FileNameLength;
DebugTrace(0, Dbg, "FatQueryDirectory -> Name = \"%Z\"\n", &Fat8Dot3String);
break;
case FileNamesInformation:
DebugTrace(0, Dbg, "FatQueryDirectory -> Getting file names information\n", 0);
NamesInfo = (PFILE_NAMES_INFORMATION)&Buffer[NextEntry];
NamesInfo->FileIndex = NextVbo;
NamesInfo->FileNameLength = FileNameLength;
DebugTrace(0, Dbg, "FatQueryDirectory -> Name = \"%Z\"\n", &Fat8Dot3String );
break;
default:
#pragma prefast( suppress:28159, "things are seriously wrong if we get here" )
FatBugCheck( FileInformationClass, 0, 0 );
}
BytesConverted = BytesRemainingInBuffer - BaseLength >= FileNameLength ?
FileNameLength :
BytesRemainingInBuffer - BaseLength;
RtlCopyMemory( &Buffer[NextEntry + BaseLength],
&LongFileName.Buffer[0],
BytesConverted );
//
// Set up the previous next entry offset
//
*((PULONG)(&Buffer[LastEntry])) = NextEntry - LastEntry;
//
// And indicate how much of the user buffer we have currently
// used up. We must compute this value before we long align
// ourselves for the next entry
//
Irp->IoStatus.Information = QuadAlign( Irp->IoStatus.Information ) +
BaseLength + BytesConverted;
//
// Check for the case that a single entry doesn't fit.
// This should only get this far on the first entry.
//
if (BytesConverted < FileNameLength) {
NT_ASSERT( NextEntry == 0 );
try_return( Status = STATUS_BUFFER_OVERFLOW );
}
}
//
// Finish up by filling in the FileId
//
switch ( FileInformationClass ) {
case FileIdBothDirectoryInformation:
IdBothDirInfo = (PFILE_ID_BOTH_DIR_INFORMATION)&Buffer[NextEntry];
IdBothDirInfo->FileId.QuadPart = FatGenerateFileIdFromDirentAndOffset( Dcb, Dirent, NextVbo );
break;
case FileIdFullDirectoryInformation:
IdFullDirInfo = (PFILE_ID_FULL_DIR_INFORMATION)&Buffer[NextEntry];
IdFullDirInfo->FileId.QuadPart = FatGenerateFileIdFromDirentAndOffset( Dcb, Dirent, NextVbo );
break;
default:
break;
}
} except (EXCEPTION_EXECUTE_HANDLER) {
//
// We had a problem filling in the user's buffer, so stop and
// fail this request. This is the only reason any exception
// would have occured at this level.
//
Irp->IoStatus.Information = 0;
UpdateCcb = FALSE;
try_return( Status = GetExceptionCode());
}
//
// Set ourselves up for the next iteration
//
LastEntry = NextEntry;
NextEntry += (ULONG)QuadAlign(BaseLength + BytesConverted);
CurrentVbo = NextVbo + sizeof( DIRENT );
}
try_exit: NOTHING;
} finally {
DebugUnwind( FatQueryDirectory );
FatReleaseFcb( IrpContext, Dcb );
//
// Unpin data in cache if still held.
//
FatUnpinBcb( IrpContext, Bcb );
//
// Free any dynamically allocated string buffer
//
FatFreeStringBuffer( &LongFileName);
//
// Perform any cleanup. If this is the first query, then store
// the filename in the Ccb if successful. Also update the
// VBO index for the next search. This is done by transferring
// from shared access to exclusive access and copying the
// data from the local copies.
//
if (!AbnormalTermination()) {
if (UpdateCcb) {
//
// Store the most recent VBO to use as a starting point for
// the next search.
//
Ccb->OffsetToStartSearchFrom = CurrentVbo;
}
FatCompleteRequest( IrpContext, Irp, Status );
}
DebugTrace(-1, Dbg, "FatQueryDirectory -> %08lx\n", Status);
}
return Status;
}
//
// Local Support Routine
//
VOID
FatGetDirTimes(
PIRP_CONTEXT IrpContext,
PDIRENT Dirent,
PFILE_DIRECTORY_INFORMATION DirInfo
)
/*++
Routine Description:
This routine pulls the date/time information from a dirent and fills
in the DirInfo structure.
Arguments:
Dirent - Supplies the dirent
DirInfo - Supplies the target structure
Return Value:
VOID
--*/
{
PAGED_CODE();
//
// Start with the Last Write Time.
//
DirInfo->LastWriteTime =
FatFatTimeToNtTime( IrpContext,
Dirent->LastWriteTime,
0 );
//
// These fields are only non-zero when in Chicago mode.
//
if (FatData.ChicagoMode) {
//
// Do a quick check here for Creation and LastAccess
// times that are the same as the LastWriteTime.
//
if (*((UNALIGNED LONG *)&Dirent->CreationTime) ==
*((UNALIGNED LONG *)&Dirent->LastWriteTime)) {
DirInfo->CreationTime.QuadPart =
DirInfo->LastWriteTime.QuadPart +
Dirent->CreationMSec * 10 * 1000 * 10;
} else {
//
// Only do the really hard work if this field is non-zero.
//
if (((PUSHORT)Dirent)[8] != 0) {
DirInfo->CreationTime =
FatFatTimeToNtTime( IrpContext,
Dirent->CreationTime,
Dirent->CreationMSec );
} else {
ExLocalTimeToSystemTime( &FatJanOne1980,
&DirInfo->CreationTime );
}
}
//
// Do a quick check for LastAccessDate.
//
if (*((PUSHORT)&Dirent->LastAccessDate) ==
*((PUSHORT)&Dirent->LastWriteTime.Date)) {
PFAT_TIME WriteTime;
WriteTime = &Dirent->LastWriteTime.Time;
DirInfo->LastAccessTime.QuadPart =
DirInfo->LastWriteTime.QuadPart -
UInt32x32To64(((WriteTime->DoubleSeconds * 2) +
(WriteTime->Minute * 60) +
(WriteTime->Hour * 60 * 60)),
1000 * 1000 * 10);
} else {
//
// Only do the really hard work if this field is non-zero.
//
if (((PUSHORT)Dirent)[9] != 0) {
DirInfo->LastAccessTime =
FatFatDateToNtTime( IrpContext,
Dirent->LastAccessDate );
} else {
ExLocalTimeToSystemTime( &FatJanOne1980,
&DirInfo->LastAccessTime );
}
}
}
}
//
// Local Support Routine
//
_Requires_lock_held_(_Global_critical_region_)
NTSTATUS
FatNotifyChangeDirectory (
IN PIRP_CONTEXT IrpContext,
IN PIRP Irp
)
/*++
Routine Description:
This routine performs the notify change directory operation. It is
responsible for either completing of enqueuing the input Irp.
Arguments:
Irp - Supplies the Irp to process
Return Value:
NTSTATUS - The return status for the operation
--*/
{
NTSTATUS Status = STATUS_SUCCESS;
PIO_STACK_LOCATION IrpSp;
PVCB Vcb;
PDCB Dcb;
PCCB Ccb;
ULONG CompletionFilter;
BOOLEAN WatchTree;
BOOLEAN CompleteRequest;
PAGED_CODE();
//
// Get the current Stack location
//
IrpSp = IoGetCurrentIrpStackLocation( Irp );
DebugTrace(+1, Dbg, "FatNotifyChangeDirectory...\n", 0);
DebugTrace( 0, Dbg, " Wait = %08lx\n", FlagOn(IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT));
DebugTrace( 0, Dbg, " Irp = %08lx\n", Irp);
DebugTrace( 0, Dbg, " ->CompletionFilter = %08lx\n", IrpSp->Parameters.NotifyDirectory.CompletionFilter);
//
// Always set the wait flag in the Irp context for the original request.
//
SetFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT );
//
// Assume we don't complete request.
//
CompleteRequest = FALSE;
//
// Check on the type of open. We return invalid parameter for all
// but UserDirectoryOpens.
//
if (FatDecodeFileObject( IrpSp->FileObject,
&Vcb,
&Dcb,
&Ccb ) != UserDirectoryOpen) {
FatCompleteRequest( IrpContext, Irp, STATUS_INVALID_PARAMETER );
DebugTrace(-1, Dbg, "FatQueryDirectory -> STATUS_INVALID_PARAMETER\n", 0);
return STATUS_INVALID_PARAMETER;
}
//
// Reference our input parameter to make things easier
//
CompletionFilter = IrpSp->Parameters.NotifyDirectory.CompletionFilter;
WatchTree = BooleanFlagOn( IrpSp->Flags, SL_WATCH_TREE );
//
// Try to acquire exclusive access to the Dcb and enqueue the Irp to the
// Fsp if we didn't get access
//
if (!FatAcquireExclusiveFcb( IrpContext, Dcb )) {
DebugTrace(0, Dbg, "FatNotifyChangeDirectory -> Cannot Acquire Fcb\n", 0);
Status = FatFsdPostRequest( IrpContext, Irp );
DebugTrace(-1, Dbg, "FatNotifyChangeDirectory -> %08lx\n", Status);
return Status;
}
try {
//
// Make sure the Fcb is still good
//
FatVerifyFcb( IrpContext, Dcb );
//
// We need the full name.
//
FatSetFullFileNameInFcb( IrpContext, Dcb );
//
// If the file is marked as DELETE_PENDING then complete this
// request immediately.
//
if (FlagOn( Dcb->FcbState, FCB_STATE_DELETE_ON_CLOSE )) {
FatRaiseStatus( IrpContext, STATUS_DELETE_PENDING );
}
//
// Call the Fsrtl package to process the request.
//
FsRtlNotifyFullChangeDirectory( Vcb->NotifySync,
&Vcb->DirNotifyList,
Ccb,
(PSTRING)&Dcb->FullFileName,
WatchTree,
FALSE,
CompletionFilter,
Irp,
NULL,
NULL );
Status = STATUS_PENDING;
CompleteRequest = TRUE;
} finally {
DebugUnwind( FatNotifyChangeDirectory );
FatReleaseFcb( IrpContext, Dcb );
//
// If the dir notify package is holding the Irp, we discard the
// the IrpContext.
//
if (CompleteRequest) {
FatCompleteRequest( IrpContext, FatNull, 0 );
}
DebugTrace(-1, Dbg, "FatNotifyChangeDirectory -> %08lx\n", Status);
}
return Status;
}
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