add read

add function that makes an ioctl call to return the driver's active mouse_modifier

3 files changed, 48 insertions, 1 deletions

diff --git a/common/common.vcxitems b/common/common.vcxitems
index d1e8db0..aeeaa95 100644
--- a/common/common.vcxitems
+++ b/common/common.vcxitems
@@ -23,6 +23,7 @@
     <ClInclude Include="$(MSBuildThisFileDirectory)accel-power.hpp" />
     <ClInclude Include="$(MSBuildThisFileDirectory)accel-sigmoid.hpp" />
     <ClInclude Include="$(MSBuildThisFileDirectory)accel-error.hpp" />
+    <ClInclude Include="$(MSBuildThisFileDirectory)rawaccel-io.hpp" />
     <ClInclude Include="$(MSBuildThisFileDirectory)rawaccel-userspace.hpp" />
     <ClInclude Include="$(MSBuildThisFileDirectory)rawaccel.hpp" />
     <ClInclude Include="$(MSBuildThisFileDirectory)x64-util.hpp" />
diff --git a/common/external/tagged-union-single.h b/common/external/tagged-union-single.h
index 3353325..f0de097 100644
--- a/common/external/tagged-union-single.h
+++ b/common/external/tagged-union-single.h
@@ -137,7 +137,7 @@ struct tagged_union {
     int tag = 0;
 
     struct storage_t {
-        alignas(max_align_of<First, Rest...>) char bytes[max_size_of<First, Rest...>] = "";
+        alignas(max_align_of<First, Rest...>) char bytes[max_size_of<First, Rest...>] = {};
 
         template <typename T>
         inline constexpr T& as() {
diff --git a/common/rawaccel-io.hpp b/common/rawaccel-io.hpp
new file mode 100644
index 0000000..5d6fad6
--- /dev/null
+++ b/common/rawaccel-io.hpp
@@ -0,0 +1,46 @@
+#pragma once
+
+#include <system_error>
+
+#define NOMINMAX
+#include <Windows.h>
+
+#include "rawaccel.hpp"
+
+#define RA_IOCTL CTL_CODE(0x8888, 0x888, METHOD_BUFFERED, FILE_ANY_ACCESS)
+
+namespace rawaccel {
+
+	mouse_modifier read() {
+		HANDLE ra_handle = INVALID_HANDLE_VALUE;
+
+		ra_handle = CreateFileW(L"\\\\.\\rawaccel", 0, 0, 0, OPEN_EXISTING, 0, 0);
+
+		if (ra_handle == INVALID_HANDLE_VALUE) {
+			throw std::system_error(GetLastError(), std::system_category(), "CreateFile failed");
+		}
+
+		mouse_modifier mod;
+		DWORD dummy;
+
+		BOOL success = DeviceIoControl(
+			ra_handle,
+			RA_IOCTL,
+			NULL,					  // input buffer
+			0,						  // input buffer size
+			&mod,                     // output buffer
+			sizeof(mouse_modifier),   // output buffer size
+			&dummy,                   // bytes returned
+			NULL                      // overlapped structure
+		);
+
+		CloseHandle(ra_handle);
+
+		if (!success) {
+			throw std::system_error(GetLastError(), std::system_category(), "DeviceIoControl failed");
+		}
+
+		return mod;
+	}
+
+}