core/legal-info: Add package dependencies with licenses to the manifest

This adds one column to the legal-info manifest table. It contains the
dependencies of the given package and their licenses. This information
is useful when assessing license compatibility of the packages and
their libraries.

An example of the content of the new column for the MPD package is
shown below:

    "alsa-lib [LGPL-2.1+ (library), GPL-2.0+ (aserver)] boost
    [BSL-1.0] libid3tag [GPL-2.0+] libmad [GPL-2.0+] libogg
    [BSD-3-Clause] libvorbis [BSD-3-Clause] libzlib [Zlib]
    skeleton-init-common [unknown] skeleton-init-sysv [unknown] sqlite
    [Public domain] toolchain-external-linaro-arm [unknown]"

[Credits to Yann E. MORIN <yann.morin.1998@free.fr> for suggesting a
few simplifications.]

Signed-off-by: Michal Sojka <sojka@merica.cz>
Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Tested-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

Makefile

@@ -798,8 +798,8 @@ legal-info-clean:
 legal-info-prepare: $(LEGAL_INFO_DIR)
 	@$(call MESSAGE,"Buildroot $(BR2_VERSION_FULL) Collecting legal info")
 	@$(call legal-license-file,buildroot,buildroot,support/legal-info/buildroot.hash,COPYING,COPYING,HOST)
-	@$(call legal-manifest,TARGET,PACKAGE,VERSION,LICENSE,LICENSE FILES,SOURCE ARCHIVE,SOURCE SITE)
-	@$(call legal-manifest,HOST,PACKAGE,VERSION,LICENSE,LICENSE FILES,SOURCE ARCHIVE,SOURCE SITE)
+	@$(call legal-manifest,TARGET,PACKAGE,VERSION,LICENSE,LICENSE FILES,SOURCE ARCHIVE,SOURCE SITE,DEPENDENCIES WITH LICENSES)
+	@$(call legal-manifest,HOST,PACKAGE,VERSION,LICENSE,LICENSE FILES,SOURCE ARCHIVE,SOURCE SITE,DEPENDENCIES WITH LICENSES)
 	@$(call legal-manifest,HOST,buildroot,$(BR2_VERSION_FULL),GPL-2.0+,COPYING,not saved,not saved)
 	@$(call legal-warning,the Buildroot source code has not been saved)
 	@cp $(BR2_CONFIG) $(LEGAL_INFO_DIR)/buildroot.config

package/pkg-generic.mk

@@ -615,6 +615,14 @@ $(2)_FINAL_ALL_DEPENDENCIES = \
 		$$($(2)_FINAL_DEPENDENCIES) \
 		$$($(2)_FINAL_EXTRACT_DEPENDENCIES) \
 		$$($(2)_FINAL_PATCH_DEPENDENCIES))
+$(2)_FINAL_RECURSIVE_DEPENDENCIES = \
+	$$(sort \
+		$$(foreach p,\
+			$$($(2)_FINAL_ALL_DEPENDENCIES),\
+			$$(p)\
+			$$($$(call UPPERCASE,$$(p))_FINAL_RECURSIVE_DEPENDENCIES)\
+		)\
+	)
 
 $(2)_INSTALL_STAGING		?= NO
 $(2)_INSTALL_IMAGES		?= NO
@@ -942,7 +950,7 @@ ifeq ($$($(2)_REDISTRIBUTE),YES)
 endif # redistribute
 
 endif # other packages
-	@$$(call legal-manifest,$$(call UPPERCASE,$(4)),$$($(2)_RAWNAME),$$($(2)_VERSION),$$($(2)_LICENSE),$$($(2)_MANIFEST_LICENSE_FILES),$$($(2)_ACTUAL_SOURCE_TARBALL),$$($(2)_ACTUAL_SOURCE_SITE))
+	@$$(call legal-manifest,$$(call UPPERCASE,$(4)),$$($(2)_RAWNAME),$$($(2)_VERSION),$$($(2)_LICENSE),$$($(2)_MANIFEST_LICENSE_FILES),$$($(2)_ACTUAL_SOURCE_TARBALL),$$($(2)_ACTUAL_SOURCE_SITE),$$(call legal-deps,$(1)))
 endif # ifneq ($$(call qstrip,$$($(2)_SOURCE)),)
 	$$(foreach hook,$$($(2)_POST_LEGAL_INFO_HOOKS),$$(call $$(hook))$$(sep))
 

package/pkg-utils.mk

@@ -79,8 +79,8 @@ define legal-warning-nosource # pkg, {local|override}
 	$(call legal-warning-pkg,$(1),sources not saved ($(2) packages not handled))
 endef
 
-define legal-manifest # {HOST|TARGET}, pkg, version, license, license-files, source, url
-	echo '"$(2)","$(3)","$(4)","$(5)","$(6)","$(7)"' >>$(LEGAL_MANIFEST_CSV_$(1))
+define legal-manifest # {HOST|TARGET}, pkg, version, license, license-files, source, url, dependencies
+	echo '"$(2)","$(3)","$(4)","$(5)","$(6)","$(7)","$(8)"' >>$(LEGAL_MANIFEST_CSV_$(1))
 endef
 
 define legal-license-file # pkgname, pkgname-pkgver, pkg-hashfile, filename, file-fullpath, {HOST|TARGET}
@@ -91,3 +91,14 @@ define legal-license-file # pkgname, pkgname-pkgver, pkg-hashfile, filename, fil
 	} && \
 	cp $(5) $(LICENSE_FILES_DIR_$(6))/$(2)/$(4)
 endef
+
+non-virtual-deps = $(foreach p,$(1),$(if $($(call UPPERCASE,$(p))_IS_VIRTUAL),,$(p)))
+
+# Returns the list of recursive dependencies and their licensing terms
+# for the package specified in parameter (in lowercase). If that
+# package is a target package, remove host packages from the list.
+legal-deps = \
+    $(foreach p,\
+        $(filter-out $(if $(1:host-%=),host-%),\
+            $(call non-virtual-deps,\
+                $($(call UPPERCASE,$(1))_FINAL_RECURSIVE_DEPENDENCIES))),$(p) [$($(call UPPERCASE,$(p))_LICENSE)])