1 files changed, 52 insertions, 0 deletions
diff --git a/circuitpython/py/usermod.cmake b/circuitpython/py/usermod.cmake
new file mode 100644
index 0000000..8532762
--- /dev/null
+++ b/circuitpython/py/usermod.cmake
@@ -0,0 +1,52 @@
+# Create a target for all user modules to link against.
+add_library(usermod INTERFACE)
+
+function(usermod_gather_sources SOURCES_VARNAME INCLUDE_DIRECTORIES_VARNAME INCLUDED_VARNAME LIB)
+    if (NOT ${LIB} IN_LIST ${INCLUDED_VARNAME})
+        list(APPEND ${INCLUDED_VARNAME} ${LIB})
+
+        # Gather library sources
+        get_target_property(lib_sources ${LIB} INTERFACE_SOURCES)
+        if (lib_sources)
+            list(APPEND ${SOURCES_VARNAME} ${lib_sources})
+        endif()
+
+        # Gather library includes
+        get_target_property(lib_include_directories ${LIB} INTERFACE_INCLUDE_DIRECTORIES)
+        if (lib_include_directories)
+            list(APPEND ${INCLUDE_DIRECTORIES_VARNAME} ${lib_include_directories})
+        endif()
+
+        # Recurse linked libraries
+        get_target_property(trans_depend ${LIB} INTERFACE_LINK_LIBRARIES)
+        if (trans_depend)
+            foreach(SUB_LIB ${trans_depend})
+                usermod_gather_sources(
+                    ${SOURCES_VARNAME}
+                    ${INCLUDE_DIRECTORIES_VARNAME}
+                    ${INCLUDED_VARNAME}
+                    ${SUB_LIB})
+            endforeach()
+        endif()
+
+        set(${SOURCES_VARNAME} ${${SOURCES_VARNAME}} PARENT_SCOPE)
+        set(${INCLUDE_DIRECTORIES_VARNAME} ${${INCLUDE_DIRECTORIES_VARNAME}} PARENT_SCOPE)
+        set(${INCLUDED_VARNAME} ${${INCLUDED_VARNAME}} PARENT_SCOPE)
+    endif()
+endfunction()
+
+# Include CMake files for user modules.
+if (USER_C_MODULES)
+    foreach(USER_C_MODULE_PATH ${USER_C_MODULES})
+        message("Including User C Module(s) from ${USER_C_MODULE_PATH}")
+        include(${USER_C_MODULE_PATH})
+    endforeach()
+endif()
+
+# Recursively gather sources for QSTR scanning - doesn't support generator expressions.
+usermod_gather_sources(MICROPY_SOURCE_USERMOD MICROPY_INC_USERMOD found_modules usermod)
+
+# Report found modules.
+list(REMOVE_ITEM found_modules "usermod")
+list(JOIN found_modules ", " found_modules)
+message("Found User C Module(s): ${found_modules}")