1################################################################################ 2# Virtual package infrastructure 3# 4# This file implements an infrastructure that eases development of 5# package .mk files for virtual packages. It should be used for all 6# virtual packages. 7# 8# See the Buildroot documentation for details on the usage of this 9# infrastructure 10# 11# In terms of implementation, this virtual infrastructure requires 12# the .mk file to only call the 'virtual-package' macro. 13# 14################################################################################ 15 16 17################################################################################ 18# inner-virtual-package -- defines the dependency rules of the virtual 19# package against its provider. 20# 21# argument 1 is the lowercase package name 22# argument 2 is the uppercase package name, including a HOST_ prefix 23# for host packages 24# argument 3 is the uppercase package name, without the HOST_ prefix 25# for host packages 26# argument 4 is the type (target or host) 27################################################################################ 28 29# Note: putting this comment here rather than in the define block, otherwise 30# make would try to expand the $(error ...) in the comment, which is not 31# really what we want. 32# We need to use second-expansion for the $(error ...) call, below, 33# so it is not evaluated now, but as part of the generated make code. 34 35define inner-virtual-package 36 37# Ensure the virtual package has an implementation defined. 38ifeq ($$(BR2_PACKAGE_HAS_$(2)),y) 39ifeq ($$(call qstrip,$$(BR2_PACKAGE_PROVIDES_$(2))),) 40$$(error No implementation selected for virtual package $(1). Configuration error) 41endif 42endif 43 44# explicitly set these so we do not get confused by environment 45# variables with the same names. 46$(2)_VERSION = 47$(2)_SOURCE = 48 49$(2)_IS_VIRTUAL = YES 50 51# Add dependency against the provider 52# For a host package, there is no corresponding BR2_PACKAGE_PROVIDES_HOST_FOO, 53# so we need to compute it from the target variant. 54ifeq ($(4),target) 55$(2)_DEPENDENCIES += $$(call qstrip,$$(BR2_PACKAGE_PROVIDES_$(2))) 56else 57ifeq ($$(call qstrip,$$(BR2_PACKAGE_PROVIDES_$(2))),) 58# Inherit from target package BR2_PACKAGE_PROVIDES_FOO 59$(2)_DEPENDENCIES += host-$$(call qstrip,$$(BR2_PACKAGE_PROVIDES_$(3))) 60else 61# BR2_PACKAGE_PROVIDES_HOST_<pkg> is explicitly defined 62$(2)_DEPENDENCIES += $$(call qstrip,$$(BR2_PACKAGE_PROVIDES_$(2))) 63endif 64endif 65 66# Call the generic package infrastructure to generate the necessary 67# make targets 68$(call inner-generic-package,$(1),$(2),$(3),$(4)) 69 70endef 71 72################################################################################ 73# virtual-package -- the target generator macro for virtual packages 74################################################################################ 75 76virtual-package = $(call inner-virtual-package,$(pkgname),$(call UPPERCASE,$(pkgname)),$(call UPPERCASE,$(pkgname)),target) 77host-virtual-package = $(call inner-virtual-package,host-$(pkgname),$(call UPPERCASE,host-$(pkgname)),$(call UPPERCASE,$(pkgname)),host) 78