Fix headers generation

Author: DataTriny

bindings/c/CMakeLists.txt

@@ -2,8 +2,9 @@ cmake_minimum_required(VERSION 3.20)
 
 project(accesskit_c)
 
+SET(ACCESSKIT_INCLUDE_DIR ${CMAKE_SOURCE_DIR}/include)
 SET(ACCESSKIT_IN_REPO ON)
-if (NOT EXISTS(${CMAKE_SOURCE_DIR}/lib))
+if (EXISTS(${CMAKE_SOURCE_DIR}/lib))
     SET(ACCESSKIT_IN_REPO OFF)
     if (WIN32)
         if (MINGW)
@@ -20,19 +21,19 @@ if (NOT EXISTS(${CMAKE_SOURCE_DIR}/lib))
             endif()
         endif()
     endif()
-endif()
-SET(ACCESSKIT_INCLUDE_DIR ${CMAKE_SOURCE_DIR}/include)
-
-if (${ACCESSKIT_IN_REPO})
-    include(ExternalProject)
+else()
     add_subdirectory(corrosion)
     corrosion_import_crate(MANIFEST_PATH Cargo.toml)
 
+    find_program(RUSTUP rustup)
+    find_program(CBINDGEN cbindgen)
+    find_program(CLANG_FORMAT clang-format)
+
     add_custom_target(headers
-        COMMAND rustup run nightly cbindgen --crate accesskit_c --output "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp" "${CMAKE_SOURCE_DIR}"
-        COMMAND clang-format -i "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp"
+        COMMAND ${RUSTUP} run nightly ${CBINDGEN} --crate accesskit_c --output "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp" "${CMAKE_SOURCE_DIR}"
+        COMMAND ${CLANG_FORMAT} -i "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp"
         COMMAND ${CMAKE_COMMAND} -E rename "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp" "${ACCESSKIT_INCLUDE_DIR}/accesskit.h"
-        DEPENDS "${ACCESSKIT_INCLUDE_DIR}/accesskit.h"
+        BYPRODUCTS "${ACCESSKIT_INCLUDE_DIR}/accesskit.h"
     )
 
     add_dependencies(cargo-prebuild_accesskit headers)