sys: notify implementation

inc/winfsp/winfsp.h

@@ -1699,6 +1699,28 @@ UINT32 FspFileSystemGetEaPackedSize(PFILE_FULL_EA_INFORMATION SingleEa)
     /* magic computations are courtesy of NTFS */
     return 5 + SingleEa->EaNameLength + SingleEa->EaValueLength;
 }
+/**
+ * Add notify information to a buffer.
+ *
+ * This is a helper for filling a buffer to use with FspFileSystemNotify.
+ *
+ * @param NotifyInfo
+ *     The notify information to add.
+ * @param Buffer
+ *     Pointer to a buffer that will receive the notify information.
+ * @param Length
+ *     Length of buffer.
+ * @param PBytesTransferred [out]
+ *     Pointer to a memory location that will receive the actual number of bytes stored. This should
+ *     be initialized to 0 prior to the first call to FspFileSystemAddNotifyInfo for a particular
+ *     buffer.
+ * @return
+ *     TRUE if the notify information was added, FALSE if there was not enough space to add it.
+ * @see
+ *     FspFileSystemNotify
+ */
+FSP_API BOOLEAN FspFileSystemAddNotifyInfo(FSP_FSCTL_NOTIFY_INFO *NotifyInfo,
+    PVOID Buffer, ULONG Length, PULONG PBytesTransferred);
 
 /*
  * Directory buffering

src/dll/fsop.c

@@ -1866,3 +1866,9 @@ FSP_API BOOLEAN FspFileSystemAddEa(PFILE_FULL_EA_INFORMATION SingleEa,
 
     return TRUE;
 }
+
+FSP_API BOOLEAN FspFileSystemAddNotifyInfo(FSP_FSCTL_NOTIFY_INFO *NotifyInfo,
+    PVOID Buffer, ULONG Length, PULONG PBytesTransferred)
+{
+    return FspFileSystemAddXxxInfo(NotifyInfo, Buffer, Length, PBytesTransferred);
+}

src/sys/volume.c

@@ -1068,10 +1068,10 @@ NTSTATUS FspVolumeStop(
 
 typedef struct
 {
-    PDEVICE_OBJECT FsvolDeviceObject;
-    PVOID InputBuffer;
-    ULONG InputBufferLength;
     WORK_QUEUE_ITEM WorkItem;
+    PDEVICE_OBJECT FsvolDeviceObject;
+    ULONG InputBufferLength;
+    FSP_FSCTL_DECLSPEC_ALIGN UINT8 InputBuffer[];
 } FSP_VOLUME_NOTIFY_WORK_ITEM;
 
 NTSTATUS FspVolumeNotify(
@@ -1108,22 +1108,14 @@ NTSTATUS FspVolumeNotify(
     if (!FspDeviceReference(FsvolDeviceObject))
         return STATUS_CANCELLED;
 
-    NotifyWorkItem = FspAllocNonPaged(sizeof *NotifyWorkItem);
+    NotifyWorkItem = FspAllocNonPaged(
+        FIELD_OFFSET(FSP_VOLUME_NOTIFY_WORK_ITEM, InputBuffer) + InputBufferLength);
     if (0 == NotifyWorkItem)
     {
         Result = STATUS_INSUFFICIENT_RESOURCES;
         goto fail;
     }
 
-    NotifyWorkItem->FsvolDeviceObject = FsvolDeviceObject;
-
-    NotifyWorkItem->InputBuffer = FspAllocNonPaged(InputBufferLength);
-    if (0 == NotifyWorkItem->InputBuffer)
-    {
-        Result = STATUS_INSUFFICIENT_RESOURCES;
-        goto fail;
-    }
-
     try
     {
         ProbeForRead(InputBuffer, InputBufferLength, 1);
@@ -1138,17 +1130,14 @@ NTSTATUS FspVolumeNotify(
     }
 
     ExInitializeWorkItem(&NotifyWorkItem->WorkItem, FspVolumeNotifyWork, NotifyWorkItem);
+    NotifyWorkItem->FsvolDeviceObject = FsvolDeviceObject;
     ExQueueWorkItem(&NotifyWorkItem->WorkItem, DelayedWorkQueue);
 
     return STATUS_SUCCESS;
 
 fail:
     if (0 != NotifyWorkItem)
-    {
-        if (0 != NotifyWorkItem->InputBuffer)
-            FspFree(NotifyWorkItem->InputBuffer);
         FspFree(NotifyWorkItem);
-    }
 
     FspDeviceDereference(FsvolDeviceObject);
 
@@ -1202,7 +1191,7 @@ static VOID FspVolumeNotifyWork(PVOID NotifyWorkItem0)
     FSP_VOLUME_NOTIFY_WORK_ITEM *NotifyWorkItem = NotifyWorkItem0;
     PDEVICE_OBJECT FsvolDeviceObject = NotifyWorkItem->FsvolDeviceObject;
     FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension = FspFsvolDeviceExtension(FsvolDeviceObject);
-    FSP_FSCTL_NOTIFY_INFO *NotifyInfo = NotifyWorkItem->InputBuffer;
+    FSP_FSCTL_NOTIFY_INFO *NotifyInfo = (PVOID)NotifyWorkItem->InputBuffer;
     PUINT8 NotifyInfoEnd = (PUINT8)NotifyInfo + NotifyWorkItem->InputBufferLength;
     ULONG NotifyInfoSize;
     UNICODE_STRING FileName = { 0 }, StreamPart = { 0 }, AbsFileName = { 0 }, FullFileName = { 0 };
@@ -1217,6 +1206,7 @@ static VOID FspVolumeNotifyWork(PVOID NotifyWorkItem0)
 
         if (sizeof(FSP_FSCTL_NOTIFY_INFO) > NotifyInfoSize)
         {
+            /* !!!: we should wait until all pending notify work is done! */
             if (1 == InterlockedCompareExchange(&FsvolDeviceExtension->VolumeNotifyLock, 0, 1))
                 FspFsvolDeviceFileRenameReleaseOwner(FsvolDeviceObject, FsvolDeviceObject);
             break;
@@ -1257,7 +1247,7 @@ static VOID FspVolumeNotifyWork(PVOID NotifyWorkItem0)
             if (NT_SUCCESS(Result))
             {
                 if (sizeof(WCHAR) * 2/* not empty or root */ <= AbsFileName.Length &&
-                    L'\\' == AbsFileName.Buffer[AbsFileName.Length / sizeof(WCHAR) - 1])
+                    L'\\' != AbsFileName.Buffer[AbsFileName.Length / sizeof(WCHAR) - 1])
                     Result = RtlAppendUnicodeToString(&FullFileName, L"\\");
             }
             if (NT_SUCCESS(Result))
@@ -1273,7 +1263,6 @@ static VOID FspVolumeNotifyWork(PVOID NotifyWorkItem0)
     if (0 != FullFileName.Buffer)
         FspFree(FullFileName.Buffer);
 
-    FspFree(NotifyWorkItem->InputBuffer);
     FspFree(NotifyWorkItem);
 
     FspDeviceDereference(FsvolDeviceObject);

tst/winfsp-tests/notify-test.c

@@ -151,6 +151,109 @@ void notify_timeout_test(void)
         notify_timeout_dotest(MemfsNet);
 }
 
+static
+void notify_change_dotest(ULONG Flags)
+{
+    void *memfs = memfs_start(Flags);
+    FSP_FILE_SYSTEM *FileSystem = MemfsFileSystem(memfs);
+    union
+    {
+        FSP_FSCTL_NOTIFY_INFO V;
+        UINT8 B[1024];
+    } Buffer;
+    ULONG Length = 0;
+    union
+    {
+        FSP_FSCTL_NOTIFY_INFO V;
+        UINT8 B[sizeof(FSP_FSCTL_NOTIFY_INFO) + MAX_PATH * sizeof(WCHAR)];
+    } NotifyInfo;
+    PWSTR FileName;
+    NTSTATUS Result;
+
+    Result = FspFileSystemNotifyBegin(FileSystem, 0);
+    ASSERT(STATUS_SUCCESS == Result);
+
+    FileName = L"\\";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    FileName = L"bar";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    FileName = L"baz";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    FileName = L"\\foo";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    FileName = L"bar";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    FileName = L"baz";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    FileName = L"\\foo\\";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    FileName = L"bar";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    FileName = L"baz";
+    NotifyInfo.V.Size = (UINT16)(sizeof(FSP_FSCTL_NOTIFY_INFO) + wcslen(FileName) * sizeof(WCHAR));
+    NotifyInfo.V.Filter = 0;
+    NotifyInfo.V.Action = 0;
+    memcpy(NotifyInfo.V.FileNameBuf, FileName, NotifyInfo.V.Size - sizeof(FSP_FSCTL_NOTIFY_INFO));
+    FspFileSystemAddNotifyInfo(&NotifyInfo.V, &Buffer, sizeof Buffer, &Length);
+
+    Result = FspFileSystemNotify(FileSystem, &Buffer.V, Length);
+    ASSERT(STATUS_SUCCESS == Result);
+
+    Result = FspFileSystemNotifyEnd(FileSystem);
+    ASSERT(STATUS_SUCCESS == Result);
+
+    memfs_stop(memfs);
+}
+
+static
+void notify_change_test(void)
+{
+    if (WinFspDiskTests)
+        notify_change_dotest(MemfsDisk);
+    if (WinFspNetTests)
+        notify_change_dotest(MemfsNet);
+}
+
 void notify_tests(void)
 {
     if (!OptExternal)
@@ -158,5 +261,6 @@ void notify_tests(void)
         TEST(notify_abandon_test);
         TEST(notify_abandon_rename_test);
         TEST(notify_timeout_test);
+        TEST(notify_change_test);
     }
 }