/*
 *  ReactOS kernel
 *  Copyright (C) 2002, 2003, 2004 ReactOS Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
/*
 * COPYRIGHT:        See COPYING in the top level directory
 * PROJECT:          ReactOS kernel
 * FILE:             drivers/filesystems/cdfs/cdfs.c
 * PURPOSE:          CDROM (ISO 9660) filesystem driver
 * PROGRAMMER:       Art Yerkes
 *                   Eric Kohl
 */

/* INCLUDES *****************************************************************/

#include "cdfs.h"

#define NDEBUG
#include <debug.h>

/* FUNCTIONS ****************************************************************/

static NTSTATUS
CdfsMakeAbsoluteFilename(PFILE_OBJECT FileObject,
                         PUNICODE_STRING RelativeFileName,
                         PUNICODE_STRING AbsoluteFileName)
{
    USHORT Length;
    PFCB Fcb;
    NTSTATUS Status;

    DPRINT("try related for %wZ\n", RelativeFileName);
    Fcb = FileObject->FsContext;
    ASSERT(Fcb);

    /* verify related object is a directory and target name
    don't start with \. */
    if ((Fcb->Entry.FileFlags & FILE_FLAG_DIRECTORY) == 0 ||
        (RelativeFileName->Length >= sizeof(WCHAR) &&
         RelativeFileName->Buffer[0] == L'\\'))
    {
        return STATUS_INVALID_PARAMETER;
    }

    /* construct absolute path name */
    Length = Fcb->PathName.Length +
        sizeof(WCHAR) +
        RelativeFileName->Length +
        sizeof(WCHAR);
    AbsoluteFileName->Length = 0;
    AbsoluteFileName->MaximumLength = Length;
    AbsoluteFileName->Buffer = ExAllocatePoolWithTag(NonPagedPool, Length, CDFS_FILENAME_TAG);
    if (AbsoluteFileName->Buffer == NULL)
    {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    Status = RtlAppendUnicodeStringToString(AbsoluteFileName,
        &Fcb->PathName);
    if (!NT_SUCCESS(Status))
    {
        RtlFreeUnicodeString(AbsoluteFileName);
        return Status;
    }

    if (!CdfsFCBIsRoot(Fcb))
    {
        Status = RtlAppendUnicodeToString(AbsoluteFileName,
            L"\\");
        if (!NT_SUCCESS(Status))
        {
            RtlFreeUnicodeString(AbsoluteFileName);
            return Status;
        }
    }

    Status = RtlAppendUnicodeStringToString(AbsoluteFileName,
        RelativeFileName);
    if (!NT_SUCCESS(Status))
    {
        RtlFreeUnicodeString(AbsoluteFileName);
        return Status;
    }

    return STATUS_SUCCESS;
}


/*
* FUNCTION: Opens a file
*/
static NTSTATUS
CdfsOpenFile(PDEVICE_EXTENSION DeviceExt,
             PFILE_OBJECT FileObject,
             PUNICODE_STRING FileName)
{
    PFCB ParentFcb;
    PFCB Fcb;
    NTSTATUS Status;
    UNICODE_STRING AbsFileName;

    DPRINT("CdfsOpenFile(%p, %p, %wZ)\n", DeviceExt, FileObject, FileName);

    if (FileObject->RelatedFileObject)
    {
        DPRINT("Converting relative filename to absolute filename\n");

        Status = CdfsMakeAbsoluteFilename(FileObject->RelatedFileObject,
            FileName,
            &AbsFileName);
        if (!NT_SUCCESS(Status))
        {
            return Status;
        }

        FileName = &AbsFileName;
    }

    Status = CdfsDeviceIoControl (DeviceExt->StorageDevice,
        IOCTL_CDROM_CHECK_VERIFY,
        NULL,
        0,
        NULL,
        0,
        FALSE);
    DPRINT ("Status %lx\n", Status);
    if (!NT_SUCCESS(Status))
    {
        DPRINT1 ("Status %lx\n", Status);
        return Status;
    }

    DPRINT("PathName to open: %wZ\n", FileName);

    /*  try first to find an existing FCB in memory  */
    DPRINT("Checking for existing FCB in memory\n");
    Fcb = CdfsGrabFCBFromTable(DeviceExt,
        FileName);
    if (Fcb == NULL)
    {
        DPRINT("No existing FCB found, making a new one if file exists.\n");
        Status = CdfsGetFCBForFile(DeviceExt,
            &ParentFcb,
            &Fcb,
            FileName);
        if (ParentFcb != NULL)
        {
            CdfsReleaseFCB(DeviceExt,
                ParentFcb);
        }

        if (!NT_SUCCESS (Status))
        {
            DPRINT("Could not make a new FCB, status: %x\n", Status);

            if (FileName == &AbsFileName)
                RtlFreeUnicodeString(&AbsFileName);

            return Status;
        }
    }

    DPRINT("Attaching FCB to fileObject\n");
    Status = CdfsAttachFCBToFileObject(DeviceExt,
        Fcb,
        FileObject);

    if ((FileName == &AbsFileName) && AbsFileName.Buffer)
        ExFreePoolWithTag(AbsFileName.Buffer, CDFS_FILENAME_TAG);

    return Status;
}


/*
* FUNCTION: Opens a file
*/
static NTSTATUS
CdfsCreateFile(PDEVICE_OBJECT DeviceObject,
               PIRP Irp)
{
    PDEVICE_EXTENSION DeviceExt;
    PIO_STACK_LOCATION Stack;
    PFILE_OBJECT FileObject;
    ULONG RequestedDisposition;
    ULONG RequestedOptions;
    PFCB Fcb;
    NTSTATUS Status;

    DPRINT("CdfsCreateFile() called\n");

    DeviceExt = DeviceObject->DeviceExtension;
    ASSERT(DeviceExt);
    Stack = IoGetCurrentIrpStackLocation (Irp);
    ASSERT(Stack);

    RequestedDisposition = ((Stack->Parameters.Create.Options >> 24) & 0xff);
    RequestedOptions = Stack->Parameters.Create.Options & FILE_VALID_OPTION_FLAGS;
    DPRINT("RequestedDisposition %x, RequestedOptions %x\n",
        RequestedDisposition, RequestedOptions);

    FileObject = Stack->FileObject;

    if (RequestedDisposition == FILE_CREATE ||
        RequestedDisposition == FILE_OVERWRITE_IF ||
        RequestedDisposition == FILE_SUPERSEDE)
    {
        return STATUS_ACCESS_DENIED;
    }

    Status = CdfsOpenFile(DeviceExt,
        FileObject,
        &FileObject->FileName);
    if (NT_SUCCESS(Status))
    {
        Fcb = FileObject->FsContext;

        /* Check whether the file has the requested attributes */
        if (RequestedOptions & FILE_NON_DIRECTORY_FILE && CdfsFCBIsDirectory(Fcb))
        {
            CdfsCloseFile (DeviceExt, FileObject);
            return STATUS_FILE_IS_A_DIRECTORY;
        }

        if (RequestedOptions & FILE_DIRECTORY_FILE && !CdfsFCBIsDirectory(Fcb))
        {
            CdfsCloseFile (DeviceExt, FileObject);
            return STATUS_NOT_A_DIRECTORY;
        }

        DeviceExt->OpenHandleCount++;
    }

    /*
    * If the directory containing the file to open doesn't exist then
    * fail immediately
    */
    Irp->IoStatus.Information = (NT_SUCCESS(Status)) ? FILE_OPENED : 0;

    return Status;
}


NTSTATUS NTAPI
CdfsCreate(
    PCDFS_IRP_CONTEXT IrpContext)
{
    PDEVICE_OBJECT DeviceObject;
    PDEVICE_EXTENSION DeviceExt;
    NTSTATUS Status;

    DPRINT("CdfsCreate()\n");

    ASSERT(IrpContext);

    DeviceObject = IrpContext->DeviceObject;
    DeviceExt = DeviceObject->DeviceExtension;
    if (BooleanFlagOn(DeviceExt->Flags, VCB_VOLUME_LOCKED))
    {
        return STATUS_ACCESS_DENIED;
    }

    if (DeviceObject == CdfsGlobalData->CdFsDeviceObject || DeviceObject == CdfsGlobalData->HddFsDeviceObject)
    {
        /* DeviceObject represents FileSystem instead of logical volume */
        DPRINT("Opening file system\n");
        IrpContext->Irp->IoStatus.Information = FILE_OPENED;
        DeviceExt->OpenHandleCount++;
        return STATUS_SUCCESS;
    }

    KeEnterCriticalRegion();
    ExAcquireResourceExclusiveLite(&DeviceExt->DirResource,
        TRUE);
    Status = CdfsCreateFile(DeviceObject,
                            IrpContext->Irp);
    ExReleaseResourceLite(&DeviceExt->DirResource);
    KeLeaveCriticalRegion();

    return Status;
}

/* EOF */