libtorch: export official CMake vars

recipes/libtorch/all/conan-official-libtorch-vars.cmake

@@ -0,0 +1,12 @@
+# ATenConfig.cmake variables
+set(ATEN_FOUND 1)
+
+# Caffe2Config.cmake variables
+set(Caffe2_MAIN_LIBS torch)
+set(CAFFE2_INCLUDE_DIRS ${${CMAKE_FIND_PACKAGE_NAME}_INCLUDE_DIRS})
+
+# TorchConfig.cmake variables
+set(TORCH_FOUND TRUE)
+set(TORCH_INCLUDE_DIRS ${${CMAKE_FIND_PACKAGE_NAME}_INCLUDE_DIRS})
+set(TORCH_LIBRARIES ${${CMAKE_FIND_PACKAGE_NAME}_LIBRARIES})
+set(TORCH_CXX_FLAGS)

recipes/libtorch/all/conanfile.py

@@ -171,6 +171,7 @@ def _is_mobile_os(self):
     def export_sources(self):
         export_conandata_patches(self)
         copy(self, "conan_deps.cmake", self.recipe_folder, os.path.join(self.export_sources_folder, "src"))
+        copy(self, "conan-official-libtorch-vars.cmake", self.recipe_folder, os.path.join(self.export_sources_folder, "src"))
 
     def config_options(self):
         if self.settings.os == "Windows":
@@ -501,6 +502,11 @@ def package(self):
         cmake.install()
         os.rename(os.path.join(self.package_folder, "share"), os.path.join(self.package_folder, "res"))
         rmdir(self, os.path.join(self.package_folder, "res", "cmake"))
+        copy(self, "conan-official-libtorch-vars.cmake", self.source_folder, os.path.join(self.package_folder, self._modules_dir))
+
+    @property
+    def _modules_dir(self):
+        return os.path.join("lib", "cmake", "Torch")
 
     def package_info(self):
         def _lib_exists(name):
@@ -583,18 +589,10 @@ def _itt():
 
         self.cpp_info.set_property("cmake_file_name", "Torch")
 
-        # TODO: export ATenConfig.cmake variables
-        # set(ATEN_FOUND 1)
-        # set(ATEN_INCLUDE_DIR "/usr/local/include")
-        # set(ATEN_LIBRARIES "")
-        # TODO: export Caffe2Config.cmake variables
-        # set(Caffe2_MAIN_LIBS torch_library)
-        # set(CAFFE2_INCLUDE_DIRS "${_INSTALL_PREFIX}/include")
-        # TODO: export TorchConfig.cmake variables
-        # TORCH_FOUND        -- True if the system has the Torch library
-        # TORCH_INCLUDE_DIRS -- The include directories for torch
-        # TORCH_LIBRARIES    -- Libraries to link against
-        # TORCH_CXX_FLAGS    -- Additional (required) compiler flags
+        # Export official CMake variables
+        self.cpp_info.builddirs.append(self._modules_dir)
+        cmake_vars_module = os.path.join(self._modules_dir, "conan-official-libtorch-vars.cmake")
+        self.cpp_info.set_property("cmake_build_modules", [cmake_vars_module])
 
         self.cpp_info.components["_headers"].includedirs.append(os.path.join("include", "torch", "csrc", "api", "include"))
         self.cpp_info.components["_headers"].resdirs = ["res"]