dll: FspFileSystemLoop

src/dll/fsctl.c

@@ -241,17 +241,24 @@ FSP_API NTSTATUS FspFsctlTransact(HANDLE VolumeHandle,
     PVOID RequestBuf, SIZE_T *PRequestBufSize)
 {
     NTSTATUS Result = STATUS_SUCCESS;
-    DWORD Bytes;
+    DWORD Bytes = 0;
+
+    if (0 != *PRequestBufSize)
+    {
+        Bytes = (DWORD)*PRequestBufSize;
+        *PRequestBufSize = 0;
+    }
 
     if (!DeviceIoControl(VolumeHandle, FSP_FSCTL_TRANSACT,
-        ResponseBuf, (DWORD)ResponseBufSize, RequestBuf, (DWORD)*PRequestBufSize,
+        ResponseBuf, (DWORD)ResponseBufSize, RequestBuf, Bytes,
         &Bytes, 0))
     {
         Result = FspNtStatusFromWin32(GetLastError());
         goto exit;
     }
 
-    *PRequestBufSize = Bytes;
+    if (0 != *PRequestBufSize)
+        *PRequestBufSize = Bytes;
 
 exit:
     return Result;

src/dll/library.h

@@ -9,7 +9,6 @@
 
 #define WINFSP_DLL_INTERNAL
 #include <winfsp/winfsp.h>
-#include <winfsp/fsctl.h>
 #include <strsafe.h>
 
 #define LIBRARY_NAME                    "WinFsp"

src/dll/loop.c

@@ -0,0 +1,144 @@
+/**
+ * @file dll/loop.c
+ *
+ * @copyright 2015 Bill Zissimopoulos
+ */
+
+#include <dll/library.h>
+
+typedef struct _FSP_WORK_ITEM
+{
+    FSP_FILE_SYSTEM *FileSystem;
+    __declspec(align(MEMORY_ALLOCATION_ALIGNMENT)) UINT8 RequestBuf[];
+} FSP_WORK_ITEM;
+
+FSP_API NTSTATUS FspFileSystemCreate(FSP_FILE_SYSTEM_PR *ProcessRequest,
+    FSP_FILE_SYSTEM **PFileSystem)
+{
+    FSP_FILE_SYSTEM *FileSystem;
+
+    *PFileSystem = 0;
+
+    if (0 == ProcessRequest)
+        return STATUS_INVALID_PARAMETER;
+
+    FileSystem = malloc(sizeof *FileSystem);
+    if (0 == FileSystem)
+        return STATUS_INSUFFICIENT_RESOURCES;
+
+    memset(FileSystem, 0, sizeof *FileSystem);
+    FileSystem->ProcessRequest = ProcessRequest;
+
+    *PFileSystem = FileSystem;
+
+    return STATUS_SUCCESS;
+}
+
+FSP_API VOID FspFileSystemDelete(FSP_FILE_SYSTEM *FileSystem)
+{
+    free(FileSystem);
+}
+
+FSP_API NTSTATUS FspFileSystemLoop(FSP_FILE_SYSTEM *FileSystem)
+{
+    NTSTATUS Result;
+    PUINT8 RequestBuf, RequestBufEnd;
+    SIZE_T RequestBufSize;
+    FSP_FSCTL_TRANSACT_REQ *Request, *NextRequest;
+
+    RequestBuf = malloc(FSP_FSCTL_TRANSACT_REQ_BUFFER_SIZEMIN);
+    if (0 == RequestBuf)
+        return STATUS_INSUFFICIENT_RESOURCES;
+
+    for (;;)
+    {
+        RequestBufSize = FSP_FSCTL_TRANSACT_REQ_BUFFER_SIZEMIN;
+        Result = FspFsctlTransact(FileSystem->VolumeHandle, 0, 0, RequestBuf, &RequestBufSize);
+        if (!NT_SUCCESS(Result))
+            goto exit;
+        RequestBufEnd = RequestBuf + RequestBufSize;
+
+        Request = (PVOID)RequestBuf;
+        for (;;)
+        {
+            NextRequest = FspFsctlTransactConsumeRequest(Request, RequestBufEnd);
+            if (0 == NextRequest)
+                break;
+
+            Result = FileSystem->ProcessRequest(FileSystem, Request);
+            if (!NT_SUCCESS(Result))
+                goto exit;
+
+            Request = NextRequest;
+        }
+    }
+
+exit:
+    free(RequestBuf);
+
+    return Result;
+}
+
+FSP_API NTSTATUS FspProcessRequestDirect(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_REQ *Request)
+{
+    if (FspFsctlTransactKindCount <= Request->Kind || 0 == FileSystem->Operations[Request->Kind])
+        return FspProduceResponseWithStatus(FileSystem, Request, STATUS_INVALID_DEVICE_REQUEST);
+
+    FileSystem->Operations[Request->Kind](FileSystem, Request);
+    return STATUS_SUCCESS;
+}
+
+static DWORD WINAPI FspProcessRequestInPoolWorker(PVOID Param)
+{
+    FSP_WORK_ITEM *WorkItem = Param;
+    FSP_FSCTL_TRANSACT_REQ *Request = (PVOID)WorkItem->RequestBuf;
+
+    WorkItem->FileSystem->Operations[Request->Kind](WorkItem->FileSystem, Request);
+    free(WorkItem);
+
+    return 0;
+}
+
+FSP_API NTSTATUS FspProcessRequestInPool(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_REQ *Request)
+{
+    if (FspFsctlTransactKindCount <= Request->Kind || 0 == FileSystem->Operations[Request->Kind])
+        return FspProduceResponseWithStatus(FileSystem, Request, STATUS_INVALID_DEVICE_REQUEST);
+
+    FSP_WORK_ITEM *WorkItem;
+    BOOLEAN Success;
+
+    WorkItem = malloc(sizeof *WorkItem + Request->Size);
+    if (0 == WorkItem)
+        return STATUS_INSUFFICIENT_RESOURCES;
+
+    WorkItem->FileSystem = FileSystem;
+    memcpy(WorkItem->RequestBuf, Request, Request->Size);
+
+    Success = QueueUserWorkItem(FspProcessRequestInPoolWorker, WorkItem, WT_EXECUTEDEFAULT);
+    if (!Success)
+    {
+        free(WorkItem);
+        return FspNtStatusFromWin32(GetLastError());
+    }
+
+    return STATUS_SUCCESS;
+}
+
+FSP_API NTSTATUS FspProduceResponse(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_RSP *Response)
+{
+    return FspFsctlTransact(FileSystem->VolumeHandle, Response, Response->Size, 0, 0);
+}
+
+FSP_API NTSTATUS FspProduceResponseWithStatus(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_REQ *Request, NTSTATUS Result)
+{
+    FSP_FSCTL_TRANSACT_RSP Response = { 0 };
+    Response.Size = sizeof Response;
+    Response.Kind = Request->Kind;
+    Response.Hint = Request->Hint;
+    Response.IoStatus.Status = Result;
+    return FspProduceResponse(FileSystem, &Response);
+}