[WDF] Add Windows Driver Framework files

Takern from Microsoft GitHub repo:
d9c6040fe9

Licensed under MIT

sdk/lib/drivers/wdf/shared/support/fxstringapi.cpp

@@ -0,0 +1,152 @@
+/*++
+
+Copyright (c) Microsoft Corporation
+
+Module Name:
+
+    FxStringApi.cpp
+
+Abstract:
+
+    This module implements the "C" interface to the collection object.
+
+Author:
+
+
+
+Environment:
+
+    Both kernel and user mode
+
+Revision History:
+
+--*/
+
+#include "FxSupportPch.hpp"
+
+extern "C"  {
+#include "FxStringAPI.tmh"
+}
+
+extern "C" {
+
+_Must_inspect_result_
+__drv_maxIRQL(PASSIVE_LEVEL)
+NTSTATUS
+WDFEXPORT(WdfStringCreate)(
+    __in
+    PWDF_DRIVER_GLOBALS DriverGlobals,
+    __in_opt
+    PCUNICODE_STRING UnicodeString,
+    __in_opt
+    PWDF_OBJECT_ATTRIBUTES StringAttributes,
+    __out
+    WDFSTRING* String
+    )
+{
+    DDI_ENTRY();
+
+    PFX_DRIVER_GLOBALS pFxDriverGlobals;
+    FxString* pString;
+    NTSTATUS status;
+
+    pFxDriverGlobals = GetFxDriverGlobals(DriverGlobals);
+
+    //
+    // Get the parent's globals if it is present
+    //
+    if (NT_SUCCESS(FxValidateObjectAttributesForParentHandle(pFxDriverGlobals,
+                                                             StringAttributes))) {
+        FxObject* pParent;
+
+        FxObjectHandleGetPtrAndGlobals(pFxDriverGlobals,
+                                       StringAttributes->ParentObject,
+                                       FX_TYPE_OBJECT,
+                                       (PVOID*)&pParent,
+                                       &pFxDriverGlobals);
+    }
+
+    FxPointerNotNull(pFxDriverGlobals, String);
+
+    *String = NULL;
+
+    status = FxVerifierCheckIrqlLevel(pFxDriverGlobals, PASSIVE_LEVEL);
+    if (!NT_SUCCESS(status)) {
+        return status;
+    }
+
+    status = FxValidateObjectAttributes(pFxDriverGlobals, StringAttributes);
+    if (!NT_SUCCESS(status)) {
+        return status;
+    }
+
+    if (UnicodeString != NULL) {
+        status = FxValidateUnicodeString(pFxDriverGlobals, UnicodeString);
+        if (!NT_SUCCESS(status)) {
+            return status;
+        }
+    }
+
+    pString = new (pFxDriverGlobals, StringAttributes) FxString(pFxDriverGlobals);
+
+    if (pString != NULL) {
+        if (UnicodeString != NULL) {
+            status = pString->Assign(UnicodeString);
+        }
+
+        if (NT_SUCCESS(status)) {
+            status = pString->Commit(StringAttributes, (WDFOBJECT*)String);
+        }
+
+        if (!NT_SUCCESS(status)) {
+            pString->DeleteFromFailedCreate();
+            pString = NULL;
+        }
+    }
+    else {
+        status = STATUS_INSUFFICIENT_RESOURCES;
+
+        DoTraceLevelMessage(
+            pFxDriverGlobals, TRACE_LEVEL_ERROR, TRACINGERROR,
+            "Could not allocate WDFSTRING handle, %!STATUS!", status);
+    }
+
+    return status;
+}
+
+__drv_maxIRQL(PASSIVE_LEVEL)
+VOID
+WDFEXPORT(WdfStringGetUnicodeString)(
+    __in
+    PWDF_DRIVER_GLOBALS DriverGlobals,
+    __in
+    WDFSTRING String,
+    __out
+    PUNICODE_STRING UnicodeString
+    )
+{
+    DDI_ENTRY();
+
+    PFX_DRIVER_GLOBALS pFxDriverGlobals;
+    FxString* pString;
+    NTSTATUS status;
+
+    FxObjectHandleGetPtrAndGlobals(GetFxDriverGlobals(DriverGlobals),
+                                   String,
+                                   FX_TYPE_STRING,
+                                   (PVOID*) &pString,
+                                   &pFxDriverGlobals);
+
+    FxPointerNotNull(pFxDriverGlobals, UnicodeString);
+
+    status = FxVerifierCheckIrqlLevel(pFxDriverGlobals, PASSIVE_LEVEL);
+    if (!NT_SUCCESS(status)) {
+        return;
+    }
+
+    RtlCopyMemory(UnicodeString,
+                  pString->GetUnicodeString(),
+                  sizeof(UNICODE_STRING));
+}
+
+} // extern "C"