Rewrite CLOn12 loader in C (#179)

* Rewrite CLOn12 loader in C

* Remove additional now-unneeded extern "C" guards for khrEnableTrace

* Fix trace message

Co-authored-by: Ben Ashbaugh <[email protected]>

Co-authored-by: Ben Ashbaugh <[email protected]>

CMakeLists.txt

@@ -69,7 +69,6 @@ set (OPENCL_ICD_LOADER_SOURCES
     loader/icd_platform.h)
 
 if (WIN32)
-    enable_language (CXX)
     list (APPEND OPENCL_ICD_LOADER_SOURCES
         loader/windows/adapter.h
         loader/windows/icd_windows.c
@@ -79,7 +78,7 @@ if (WIN32)
         loader/windows/icd_windows_envvars.c
         loader/windows/icd_windows_hkr.c
         loader/windows/icd_windows_hkr.h
-        loader/windows/icd_windows_apppackage.cpp
+        loader/windows/icd_windows_apppackage.c
         loader/windows/icd_windows_apppackage.h
         loader/windows/OpenCL.def
         loader/windows/OpenCL.rc)

loader/icd.h

@@ -85,13 +85,7 @@ struct KHRicdVendorRec
 // the global state
 extern KHRicdVendor * khrIcdVendors;
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-    extern int khrEnableTrace;
-#ifdef __cplusplus
-}
-#endif
+extern int khrEnableTrace;
 
 #if defined(CL_ENABLE_LAYERS)
 /*

loader/windows/icd_windows_apppackage.c

@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2017-2019 The Khronos Group Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * OpenCL is a trademark of Apple Inc. used under license by Khronos.
+ */
+
+#include <icd.h>
+#include "icd_windows_apppackage.h"
+
+#ifdef OPENCL_ICD_LOADER_DISABLE_OPENCLON12
+
+bool khrIcdOsVendorsEnumerateAppPackage(void)
+{
+    KHR_ICD_TRACE("OpenCLOn12 is disabled\n");
+    return false;
+}
+
+#else
+
+#include <AppModel.h>
+
+bool khrIcdOsVendorsEnumerateAppPackage(void)
+{
+    UINT32 numPackages = 0, bufferLength = 0;
+    PCWSTR familyName = L"Microsoft.D3DMappingLayers_8wekyb3d8bbwe";
+    if (ERROR_INSUFFICIENT_BUFFER != GetPackagesByPackageFamily(familyName,
+                                                                &numPackages, NULL,
+                                                                &bufferLength, NULL) ||
+        numPackages == 0 || bufferLength == 0)
+    {
+        KHR_ICD_TRACE("Failed to find mapping layers packages by family name\n");
+        return false;
+    }
+
+    bool ret = false;
+    WCHAR *buffer = malloc(sizeof(WCHAR) * bufferLength);
+    PWSTR *packages = malloc(sizeof(PWSTR) * numPackages);
+    if (!buffer || !packages)
+    {
+        KHR_ICD_TRACE("Failed to allocate memory for package names\n");
+        goto cleanup;
+    }
+
+    if (ERROR_SUCCESS != GetPackagesByPackageFamily(familyName,
+                                                    &numPackages, packages,
+                                                    &bufferLength, buffer))
+    {
+        KHR_ICD_TRACE("Failed to get mapping layers package full names\n");
+        goto cleanup;
+    }
+
+    UINT32 pathLength = 0;
+    WCHAR path[MAX_PATH];
+    if (ERROR_INSUFFICIENT_BUFFER != GetPackagePathByFullName(packages[0], &pathLength, NULL) ||
+        pathLength > MAX_PATH ||
+        ERROR_SUCCESS != GetPackagePathByFullName(packages[0], &pathLength, path))
+    {
+        KHR_ICD_TRACE("Failed to get mapping layers package path length\n");
+        goto cleanup;
+    }
+
+#if defined(_M_AMD64)
+#define PLATFORM_PATH L"x64"
+#elif defined(_M_ARM)
+#define PLATFORM_PATH L"arm"
+#elif defined(_M_ARM64)
+#define PLATFORM_PATH L"arm64"
+#elif defined(_M_IX86)
+#define PLATFORM_PATH L"x86"
+#endif
+
+    wchar_t dllPath[MAX_PATH];
+    wcscpy_s(dllPath, MAX_PATH, path);
+    wcscat_s(dllPath, MAX_PATH, L"\\" PLATFORM_PATH L"\\OpenCLOn12.dll");
+
+    char narrowDllPath[MAX_PATH];
+    WideCharToMultiByte(CP_ACP, 0, dllPath, -1, narrowDllPath, MAX_PATH, NULL, NULL);
+
+    ret = adapterAdd(narrowDllPath, ZeroLuid);
+
+cleanup:
+    free(buffer);
+    free(packages);
+    return ret;
+}
+
+#endif

loader/windows/icd_windows_apppackage.h

@@ -19,7 +19,4 @@
 #include <stdbool.h>
 #include "icd_windows.h"
 
-#ifdef __cplusplus
-extern "C"
-#endif
 bool khrIcdOsVendorsEnumerateAppPackage(void);