buildsystem: implement EXTERNAL_PKG_DIRS feature

Kconfig

@@ -34,9 +34,13 @@ rsource "sys/Kconfig"
 rsource "pkg/Kconfig"
 
 menu "External Modules"
-osource "$(KCONFIG_EXTERNAL_CONFIGS)"
+osource "$(KCONFIG_EXTERNAL_MODULE_CONFIGS)"
 endmenu # External Modules
 
+menu "External Packages"
+osource "$(KCONFIG_EXTERNAL_PKG_CONFIGS)"
+endmenu # External Packages
+
 comment "RIOT is in a migration phase."
 comment "Some configuration options may not be here. Use CFLAGS instead."
 

Makefile.include

@@ -49,6 +49,7 @@ EXTERNAL_BOARD_DIRS             ?=
 RIOTMAKE                        ?= $(RIOTBASE)/makefiles
 RIOTKCONFIG                     ?= $(RIOTBASE)/kconfigs
 RIOTPKG                         ?= $(RIOTBASE)/pkg
+EXTERNAL_PKG_DIRS               ?=
 RIOTTOOLS                       ?= $(RIOTBASE)/dist/tools
 RIOTPROJECT                     ?= $(shell git rev-parse --show-toplevel 2>/dev/null || pwd)
 BUILD_DIR                       ?= $(RIOTBASE)/build
@@ -98,6 +99,9 @@ ifeq ($(INSIDE_DOCKER),0)
   ifeq ($(origin EXTERNAL_MODULE_DIRS),command line)
     $(error EXTERNAL_MODULE_DIRS must be passed as environment variable, and not as command line argument)
   endif
+  ifeq ($(origin EXTERNAL_PKG_DIRS),command line)
+    $(error EXTERNAL_PKG_DIRS must be passed as environment variable, and not as command line argument)
+  endif
 endif
 
 # Deprecation of configuring 'RIOTBOARD'
@@ -142,6 +146,9 @@ EXTERNAL_BOARD_DIRS             := $(foreach dir,\
 EXTERNAL_MODULE_DIRS            := $(foreach dir,\
                                              $(EXTERNAL_MODULE_DIRS),\
                                              $(abspath $(dir)))
+EXTERNAL_PKG_DIRS               := $(foreach dir,\
+                                             $(EXTERNAL_PKG_DIRS),\
+                                             $(abspath $(dir)))
 
 # Ensure that all directories are set and don't contain spaces.
 ifneq (, $(filter-out 1, $(foreach v,$(__DIRECTORY_VARIABLES),$(words $($(v))))))
@@ -428,8 +435,9 @@ ifeq (1,$(TEST_KCONFIG))
   KCONFIG_PACKAGES := $(call lowercase,$(patsubst CONFIG_PACKAGE_%,%,$(filter CONFIG_PACKAGE_%,$(.VARIABLES))))
   USEPKG := $(KCONFIG_PACKAGES)
 
-  # Locate used packages in $(RIOTPKG).
-  PKG_PATHS := $(sort $(foreach dir,$(RIOTPKG),\
+  # Locate used packages in $(RIOTPKG) or $(EXTERNAL_PKG_DIRS).
+  PKGDIRS := $(RIOTPKG) $(EXTERNAL_PKG_DIRS)
+  PKG_PATHS := $(sort $(foreach dir,$(PKGDIRS),\
     $(foreach pkg,$(USEPKG),$(dir $(wildcard $(dir)/$(pkg)/Makefile)))))
 
   EXTERNAL_MODULE_PATHS := $(dir $(EXTERNAL_MODULE_KCONFIGS))

makefiles/dependency_resolution.inc.mk

@@ -6,8 +6,9 @@
 EXTERNAL_MODULE_PATHS := $(sort $(foreach dir,$(EXTERNAL_MODULE_DIRS),\
   $(foreach mod,$(USEMODULE),$(dir $(wildcard $(dir)/$(mod)/Makefile)))))
 
-# Locate used packages in $(RIOTPKG).
-PKG_PATHS := $(sort $(foreach dir,$(RIOTPKG),\
+# Locate used packages in $(RIOTPKG) or $(EXTERNAL_PKG_DIRS).
+PKGDIRS := $(RIOTPKG) $(EXTERNAL_PKG_DIRS)
+PKG_PATHS := $(sort $(foreach dir,$(PKGDIRS),\
   $(foreach pkg,$(USEPKG),$(dir $(wildcard $(dir)/$(pkg)/Makefile)))))
 
 # Back up current state to detect changes

makefiles/kconfig.mk

@@ -27,7 +27,10 @@ export KCONFIG_AUTOHEADER_HEADER
 export KCONFIG_GENERATED_DEPENDENCIES = $(GENERATED_DIR)/Kconfig.dep
 
 # This file will contain external module configurations
-export KCONFIG_EXTERNAL_CONFIGS = $(GENERATED_DIR)/Kconfig.external_modules
+export KCONFIG_EXTERNAL_MODULE_CONFIGS = $(GENERATED_DIR)/Kconfig.external_modules
+
+# This file will contain external package configurations
+export KCONFIG_EXTERNAL_PKG_CONFIGS = $(GENERATED_DIR)/Kconfig.external_pkgs
 
 # Add configurations that only work when running the Kconfig test so far,
 # because they activate modules.
@@ -183,8 +186,8 @@ EXTERNAL_MODULE_KCONFIGS ?= $(sort $(foreach dir,$(EXTERNAL_MODULE_DIRS),\
                               $(wildcard $(dir)/*/Kconfig)))
 # Build a Kconfig file that source all external modules configuration
 # files. Every EXTERNAL_MODULE_DIRS with a Kconfig file is written to
-# KCONFIG_EXTERNAL_CONFIGS as 'osource dir/Kconfig'
-$(KCONFIG_EXTERNAL_CONFIGS): FORCE | $(GENERATED_DIR)
+# KCONFIG_EXTERNAL_MODULE_CONFIGS as 'osource dir/Kconfig'
+$(KCONFIG_EXTERNAL_MODULE_CONFIGS): FORCE | $(GENERATED_DIR)
 	$(Q)\
 	if [ -n "$(EXTERNAL_MODULE_KCONFIGS)" ] ; then  \
 		printf "%s\n" $(EXTERNAL_MODULE_KCONFIGS) \
@@ -195,6 +198,24 @@ $(KCONFIG_EXTERNAL_CONFIGS): FORCE | $(GENERATED_DIR)
 		| $(LAZYSPONGE) $(LAZYSPONGE_FLAGS) $@ ; \
 	fi
 
+# All directories in EXTERNAL_PKG_DIRS which have a subdirectory containing a
+# Kconfig file.
+EXTERNAL_PKG_KCONFIGS ?= $(sort $(foreach dir,$(EXTERNAL_PKG_DIRS),\
+                              $(wildcard $(dir)/*/Kconfig)))
+# Build a Kconfig file that sources all external packages configuration
+# files. Every directory with a Kconfig file is written to KCONFIG_PKG_CONFIGS
+# as 'osource dir/Kconfig'
+$(KCONFIG_EXTERNAL_PKG_CONFIGS): FORCE | $(GENERATED_DIR)
+	$(Q)\
+	if [ -n "$(EXTERNAL_PKG_KCONFIGS)" ] ; then  \
+		printf "%s\n" $(EXTERNAL_PKG_KCONFIGS) \
+		| awk '{ printf "osource \"%s\"\n", $$0 }' \
+		| $(LAZYSPONGE) $(LAZYSPONGE_FLAGS) $@ ; \
+	else \
+		printf "# no external packages" \
+		| $(LAZYSPONGE) $(LAZYSPONGE_FLAGS) $@ ; \
+	fi
+
 # When the 'clean' target is called, the files inside GENERATED_DIR should be
 # regenerated. For that, we conditionally change GENERATED_DIR from an 'order
 # only' requisite to a normal one.
@@ -211,7 +232,7 @@ GENERATED_DIR_DEP := $(if $(CLEAN),,|) $(GENERATED_DIR)
 # Generates a .config file by merging multiple sources specified in
 # MERGE_SOURCES. This will also generate KCONFIG_OUT_DEP with the list of used
 # Kconfig files.
-$(KCONFIG_OUT_CONFIG): $(KCONFIG_EXTERNAL_CONFIGS)
+$(KCONFIG_OUT_CONFIG): $(KCONFIG_EXTERNAL_MODULE_CONFIGS) $(KCONFIG_EXTERNAL_PKG_CONFIGS)
 $(KCONFIG_OUT_CONFIG): $(GENERATED_DEPENDENCIES_DEP) $(GENCONFIG) $(MERGE_SOURCES) $(GENERATED_DIR_DEP)
 	$(Q) $(GENCONFIG) \
 	  --config-out=$(KCONFIG_OUT_CONFIG) \

tests/external_pkg_dirs/app.config.test

@@ -0,0 +1 @@
+CONFIG_PACKAGE_EXTERNAL_PKG=y