drivers/ksfilter/ks/misc.c

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS Kernel Streaming
   4  * FILE:            drivers/ksfilter/ks/misc.c
   5  * PURPOSE:         KS Allocator functions
   6  * PROGRAMMER:      Johannes Anderwald
   7  */
   8
   9
  10 #include "priv.h"
  11
  12 PVOID
  13 AllocateItem(
  14     IN POOL_TYPE PoolType,
  15     IN SIZE_T NumberOfBytes)
  16 {
  17     PVOID Item = ExAllocatePool(PoolType, NumberOfBytes);
  18     if (!Item)
  19         return Item;
  20
  21     RtlZeroMemory(Item, NumberOfBytes);
  22     return Item;
  23 }
  24
  25 VOID
  26 FreeItem(
  27     IN PVOID Item)
  28 {
  29
  30     ExFreePool(Item);
  31 }
  32
  33 NTSTATUS
  34 NTAPI
  35 KspForwardIrpSynchronousCompletion(
  36     IN PDEVICE_OBJECT  DeviceObject,
  37     IN PIRP  Irp,
  38     IN PVOID  Context)
  39 {
  40     if (Irp->PendingReturned == TRUE)
  41     {
  42         KeSetEvent ((PKEVENT) Context, IO_NO_INCREMENT, FALSE);
  43     }
  44     return STATUS_MORE_PROCESSING_REQUIRED;
  45 }
  46
  47
  48 NTSTATUS
  49 KspForwardIrpSynchronous(
  50     IN  PDEVICE_OBJECT DeviceObject,
  51     IN  PIRP Irp)
  52 {
  53     KEVENT Event;
  54     NTSTATUS Status;
  55     PDEVICE_EXTENSION DeviceExtension;
  56     PKSIDEVICE_HEADER DeviceHeader;
  57
  58     ASSERT_IRQL_EQUAL(PASSIVE_LEVEL);
  59
  60     /* get device extension */
  61     DeviceExtension = (PDEVICE_EXTENSION)DeviceObject->DeviceExtension;
  62     /* get device header */
  63     DeviceHeader = DeviceExtension->DeviceHeader;
  64
  65     /* initialize the notification event */
  66     KeInitializeEvent(&Event, NotificationEvent, FALSE);
  67
  68     IoCopyCurrentIrpStackLocationToNext(Irp);
  69
  70     IoSetCompletionRoutine(Irp, KspForwardIrpSynchronousCompletion, (PVOID)&Event, TRUE, TRUE, TRUE);
  71
  72     /* now call the driver */
  73     Status = IoCallDriver(DeviceHeader->BaseDevice, Irp);
  74     /* did the request complete yet */
  75     if (Status == STATUS_PENDING)
  76     {
  77         /* not yet, lets wait a bit */
  78         KeWaitForSingleObject(&Event, Executive, KernelMode, FALSE, NULL);
  79         Status = Irp->IoStatus.Status;
  80     }
  81     return Status;
  82 }
  83
  84 NTSTATUS
  85 KspCopyCreateRequest(
  86     IN PIRP Irp,
  87     IN LPWSTR ObjectClass,
  88     IN OUT PULONG Size,
  89     OUT PVOID * Result)
  90 {
  91     PIO_STACK_LOCATION IoStack;
  92     ULONG ObjectLength, ParametersLength;
  93     PVOID Buffer;
  94
  95     /* get current irp stack */
  96     IoStack = IoGetCurrentIrpStackLocation(Irp);
  97
  98     /* get object class length */
  99     ObjectLength = (wcslen(ObjectClass) + 2) * sizeof(WCHAR);
 100
 101     /* check for minium length requirement */
 102     if (ObjectLength  + *Size > IoStack->FileObject->FileName.MaximumLength)
 103         return STATUS_UNSUCCESSFUL;
 104
 105     /* extract parameters length */
 106     ParametersLength = IoStack->FileObject->FileName.MaximumLength - ObjectLength;
 107
 108     /* allocate buffer */
 109     Buffer = AllocateItem(NonPagedPool, ParametersLength);
 110     if (!Buffer)
 111         return STATUS_INSUFFICIENT_RESOURCES;
 112
 113     /* copy parameters */
 114     RtlMoveMemory(Buffer, &IoStack->FileObject->FileName.Buffer[ObjectLength / sizeof(WCHAR)], ParametersLength);
 115
 116     /* store result */
 117     *Result = Buffer;
 118     *Size = ParametersLength;
 119
 120     return STATUS_SUCCESS;
 121 }
 122
 123 /*
 124     @implemented
 125 */
 126 KSDDKAPI
 127 PVOID
 128 NTAPI
 129 KsGetObjectFromFileObject(
 130     IN PFILE_OBJECT FileObject)
 131 {
 132     PKSIOBJECT_HEADER ObjectHeader;
 133
 134     /* get object header */
 135     ObjectHeader = (PKSIOBJECT_HEADER)FileObject->FsContext2;
 136
 137     /* return associated object */
 138     return ObjectHeader->ObjectType;
 139 }
 140
 141 /*
 142     @implemented
 143 */
 144 KSDDKAPI
 145 KSOBJECTTYPE
 146 NTAPI
 147 KsGetObjectTypeFromFileObject(
 148     IN PFILE_OBJECT FileObject)
 149 {
 150     PKSIOBJECT_HEADER ObjectHeader;
 151
 152     /* get object header */
 153     ObjectHeader = (PKSIOBJECT_HEADER)FileObject->FsContext2;
 154     /* return type */
 155     return ObjectHeader->Type;
 156 }
 157
 158 /*
 159     @implemented
 160 */
 161 KSOBJECTTYPE
 162 NTAPI
 163 KsGetObjectTypeFromIrp(
 164     IN PIRP  Irp)
 165 {
 166     PKSIOBJECT_HEADER ObjectHeader;
 167     PIO_STACK_LOCATION IoStack;
 168
 169     /* get current irp stack */
 170     IoStack = IoGetCurrentIrpStackLocation(Irp);
 171     /* get object header */
 172     ObjectHeader = (PKSIOBJECT_HEADER)IoStack->FileObject->FsContext2;
 173     /* return type */
 174     return ObjectHeader->Type;
 175 }
 176
 177 /*
 178     @unimplemented
 179 */
 180 PUNKNOWN
 181 NTAPI
 182 KsGetOuterUnknown(
 183     IN PVOID  Object)
 184 {
 185     UNIMPLEMENTED
 186     return NULL;
 187
 188 }
 189
 190 /*
 191     @implemented
 192 */
 193 KSDDKAPI
 194 PVOID
 195 NTAPI
 196 KsGetParent(
 197     IN PVOID Object)
 198 {
 199     PKSBASIC_HEADER BasicHeader = (PKSBASIC_HEADER)((ULONG_PTR)Object - sizeof(KSBASIC_HEADER));
 200     /* sanity check */
 201     ASSERT(BasicHeader->Parent.KsDevice != NULL);
 202     /* return object type */
 203     return (PVOID)BasicHeader->Parent.KsDevice;
 204 }
 205
 206