[pschweitzer] 49716: [NTOSKRNL] - Implemented FsRtlLookupPerStreamContextInternal(), FsRtlInsertPerStreamContext(), FsRtlRemovePerStreamContext(), FsRtlTeardownPerStreamContexts() Based on my previ...

Author: pschweitzer
Date: Mon Nov 22 23:30:01 2010
New Revision: 49716

URL: http://svn.reactos.org/svn/reactos?rev=49716&view=rev
Log:
[NTOSKRNL]
- Implemented FsRtlLookupPerStreamContextInternal(), FsRtlInsertPerStreamContext(),
FsRtlRemovePerStreamContext(), FsRtlTeardownPerStreamContexts()
Based on my previous work on pierre-fsd branch.

Modified:
    trunk/reactos/ntoskrnl/fsrtl/filtrctx.c

Modified: trunk/reactos/ntoskrnl/fsrtl/filtrctx.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/fsrtl/filtrctx.c?…
==============================================================================
--- trunk/reactos/ntoskrnl/fsrtl/filtrctx.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/fsrtl/filtrctx.c [iso-8859-1] Mon Nov 22 23:30:01 2010
@@ -3,7 +3,7 @@
  * LICENSE:         GPL - See COPYING in the top level directory
  * FILE:            ntoskrnl/fsrtl/filtrctx.c
  * PURPOSE:         File Stream Filter Context support for File System Drivers
- * PROGRAMMERS:     None.
+ * PROGRAMMERS:     Pierre Schweitzer (pierre.schweitzer(a)reactos.org)
  */
 
 /* INCLUDES ******************************************************************/
@@ -36,16 +36,51 @@
 }
 
 /*
- * @unimplemented
+ * @implemented
  */
 PFSRTL_PER_STREAM_CONTEXT
 NTAPI
-FsRtlLookupPerStreamContextInternal(IN PFSRTL_ADVANCED_FCB_HEADER StreamContext,
+FsRtlLookupPerStreamContextInternal(IN PFSRTL_ADVANCED_FCB_HEADER AdvFcbHeader,
                                     IN PVOID OwnerId OPTIONAL,
                                     IN PVOID InstanceId OPTIONAL)
 {
-    KeBugCheck(FILE_SYSTEM);
-    return FALSE;
+    PLIST_ENTRY NextEntry;
+    PFSRTL_PER_STREAM_CONTEXT TmpPerStreamContext, PerStreamContext = NULL;
+
+    ASSERT(AdvFcbHeader);
+    ASSERT(FlagOn(AdvFcbHeader->Flags2, FSRTL_FLAG2_SUPPORTS_FILTER_CONTEXTS));
+
+    ExAcquireFastMutex(AdvFcbHeader->FastMutex);
+
+    /* If list is empty, no need to browse it */
+    if (!IsListEmpty(&(AdvFcbHeader->FilterContexts)))
+    {
+        for (NextEntry = AdvFcbHeader->FilterContexts.Flink;
+             NextEntry != &(AdvFcbHeader->FilterContexts);
+             NextEntry = NextEntry->Flink)
+        {
+            /* If we don't have any criteria for search, first entry will be enough
*/
+            if (!OwnerId && !InstanceId)
+            {
+                PerStreamContext = (PFSRTL_PER_STREAM_CONTEXT)NextEntry;
+                break;
+            }
+            /* Else, we've to find something that matches with the parameters. */
+            else
+            {
+                TmpPerStreamContext = CONTAINING_RECORD(NextEntry,
FSRTL_PER_STREAM_CONTEXT, Links);
+                if ((InstanceId && TmpPerStreamContext->InstanceId ==
InstanceId && TmpPerStreamContext->OwnerId == OwnerId) ||
+                    (OwnerId && TmpPerStreamContext->OwnerId == OwnerId))
+                {
+                    PerStreamContext = TmpPerStreamContext;
+                    break;
+                }
+            }
+        }
+    }
+    ExReleaseFastMutex(AdvFcbHeader->FastMutex);
+
+    return PerStreamContext;
 }
 
 /*
@@ -62,28 +97,77 @@
 }
 
 /*
- * @unimplemented
+ * @implemented
  */
 NTSTATUS
 NTAPI
-FsRtlInsertPerStreamContext(IN PFSRTL_ADVANCED_FCB_HEADER PerStreamContext,
-                            IN PFSRTL_PER_STREAM_CONTEXT Ptr)
-{
-    KeBugCheck(FILE_SYSTEM);
-    return STATUS_NOT_IMPLEMENTED;
-}
-
-/*
- * @unimplemented
+FsRtlInsertPerStreamContext(IN PFSRTL_ADVANCED_FCB_HEADER AdvFcbHeader,
+                            IN PFSRTL_PER_STREAM_CONTEXT PerStreamContext)
+{
+    if (!(AdvFcbHeader) || !(AdvFcbHeader->Flags2 &
FSRTL_FLAG2_SUPPORTS_FILTER_CONTEXTS))
+    {
+        return STATUS_INVALID_DEVICE_REQUEST;
+    }
+
+    ExAcquireFastMutex(AdvFcbHeader->FastMutex);
+    InsertHeadList(&(AdvFcbHeader->FilterContexts),
&(PerStreamContext->Links));
+    ExReleaseFastMutex(AdvFcbHeader->FastMutex);
+    return STATUS_SUCCESS;
+}
+
+/*
+ * @implemented
  */
 PFSRTL_PER_STREAM_CONTEXT
 NTAPI
-FsRtlRemovePerStreamContext(IN PFSRTL_ADVANCED_FCB_HEADER StreamContext,
+FsRtlRemovePerStreamContext(IN PFSRTL_ADVANCED_FCB_HEADER AdvFcbHeader,
                             IN PVOID OwnerId OPTIONAL,
                             IN PVOID InstanceId OPTIONAL)
 {
-    KeBugCheck(FILE_SYSTEM);
-    return NULL;
+    PLIST_ENTRY NextEntry;
+    PFSRTL_PER_STREAM_CONTEXT TmpPerStreamContext, PerStreamContext = NULL;
+
+    if (!(AdvFcbHeader) || !(AdvFcbHeader->Flags2 &
FSRTL_FLAG2_SUPPORTS_FILTER_CONTEXTS))
+    {
+        return NULL;
+    }
+
+    ExAcquireFastMutex(AdvFcbHeader->FastMutex);
+    /* If list is empty, no need to browse it */
+    if (!IsListEmpty(&(AdvFcbHeader->FilterContexts)))
+    {
+        for (NextEntry = AdvFcbHeader->FilterContexts.Flink;
+             NextEntry != &(AdvFcbHeader->FilterContexts);
+             NextEntry = NextEntry->Flink)
+        {
+            /* If we don't have any criteria for search, first entry will be enough
*/
+            if (!OwnerId && !InstanceId)
+            {
+                PerStreamContext = (PFSRTL_PER_STREAM_CONTEXT)NextEntry;
+                break;
+            }
+            /* Else, we've to find something that matches with the parameters. */
+            else
+            {
+                TmpPerStreamContext = CONTAINING_RECORD(NextEntry,
FSRTL_PER_STREAM_CONTEXT, Links);
+                if ((InstanceId && TmpPerStreamContext->InstanceId ==
InstanceId && TmpPerStreamContext->OwnerId == OwnerId) ||
+                    (OwnerId && TmpPerStreamContext->OwnerId == OwnerId))
+                {
+                    PerStreamContext = TmpPerStreamContext;
+                    break;
+                }
+            }
+        }
+        /* Finally remove entry from list */
+        if (PerStreamContext)
+        {
+            RemoveEntryList(&(PerStreamContext->Links));
+        }
+    }
+    ExReleaseFastMutex(AdvFcbHeader->FastMutex);
+
+    return PerStreamContext;
+
 }
 
 /*
@@ -112,12 +196,49 @@
 }
 
 /*
- * @unimplemented
+ * @implemented
  */
 VOID
 NTAPI
-FsRtlTeardownPerStreamContexts(IN PFSRTL_ADVANCED_FCB_HEADER AdvancedHeader)
-{
-    KeBugCheck(FILE_SYSTEM);
-}
-
+FsRtlTeardownPerStreamContexts(IN PFSRTL_ADVANCED_FCB_HEADER AdvFcbHeader)
+{
+    PLIST_ENTRY NextEntry;
+    BOOLEAN IsMutexLocked = FALSE;
+    PFSRTL_PER_STREAM_CONTEXT PerStreamContext;
+
+    _SEH2_TRY
+    {
+        /* Acquire mutex to deal with the list */
+        ExAcquireFastMutex(AdvFcbHeader->FastMutex);
+        IsMutexLocked = TRUE;
+
+        /* While there are items... */
+        while (!IsListEmpty(&(AdvFcbHeader->FilterContexts)))
+        {
+            /* ...remove one */
+            NextEntry = RemoveHeadList(&(AdvFcbHeader->FilterContexts));
+            PerStreamContext = CONTAINING_RECORD(NextEntry, FSRTL_PER_STREAM_CONTEXT,
Links);
+
+            /* Release mutex before calling callback */
+            ExReleaseFastMutex(AdvFcbHeader->FastMutex);
+            IsMutexLocked = FALSE;
+
+            /* Call the callback */
+            ASSERT(PerStreamContext->FreeCallback);
+            (*PerStreamContext->FreeCallback)(PerStreamContext);
+
+            /* Relock the list to continue */
+            ExAcquireFastMutex(AdvFcbHeader->FastMutex);
+            IsMutexLocked = TRUE;
+        }
+    }
+    _SEH2_FINALLY
+    {
+        /* If mutex was locked, release */
+        if (IsMutexLocked)
+        {
+            ExReleaseFastMutex(AdvFcbHeader->FastMutex);
+        }
+    }
+    _SEH2_END;
+}