make/subdir.mk

   1 # This file is intended to be included from each subdirectory makefile.
   2 #
   3 # Subdirectory makefiles must define:
   4 #   SubDirs - The subdirectories to traverse.
   5 #   ObjNames - The objects available in that directory.
   6 #   Implementation - The library configuration the objects should go in (Generic
   7 #                    or Optimized)
   8 #   Dependencies - Any dependences for the object files.
   9 #
  10 # Subdirectory makefiles may define:
  11 #   OnlyArchs - Only build the objects for the listed archs.
  12 #   OnlyConfigs - Only build the objects for the listed configurations.
  13
  14 ifeq ($(Dir),)
  15   $(error "No Dir variable defined.")
  16 endif
  17
  18 ###
  19 # Include child makefile fragments
  20
  21 # The list of variables which are intended to be overridden in a subdirectory
  22 # makefile.
  23 RequiredSubdirVariables := \
  24         ModuleName SubDirs ObjNames Implementation Dependencies
  25 OptionalSubdirVariables := OnlyArchs OnlyConfigs
  26
  27 # Template: subdir_traverse_template subdir
  28 define subdir_traverse_template
  29 $(call Set,Dir,$(1))
  30 ifneq ($(DEBUGMAKE),)
  31   $$(info MAKE: $(Dir): Processing subdirectory)
  32 endif
  33
  34 # Construct the variable key for this directory.
  35 $(call Set,DirKey,SubDir.$(subst .,,$(subst /,__,$(1))))
  36 $(call Append,SubDirKeys,$(DirKey))
  37 $(call Set,$(DirKey).Dir,$(Dir))
  38
  39 # Reset subdirectory specific variables to sentinel value.
  40 $$(foreach var,$$(RequiredSubdirVariables) $$(OptionalSubdirVariables),\
  41   $$(call Set,$$(var),UNDEFINED))
  42
  43 # Get the subdirectory variables.
  44 include $(1)/Makefile.mk
  45
  46 ifeq ($(DEBUGMAKE),2)
  47 $$(foreach var,$(RequiredSubdirVariables) $(OptionalSubdirVariables),\
  48   $$(if $$(call strneq,UNDEFINED,$$($$(var))), \
  49         $$(info MAKE: $(Dir): $$(var) is defined), \
  50         $$(info MAKE: $(Dir): $$(var) is undefined)))
  51 endif
  52
  53 # Check for undefined required variables, and unset sentinel value from optional
  54 # variables.
  55 $$(foreach var,$(RequiredSubdirVariables),\
  56   $$(if $$(call strneq,UNDEFINED,$$($$(var))),, \
  57         $$(error $(Dir): variable '$$(var)' was not undefined)))
  58 $$(foreach var,$(OptionalSubdirVariables),\
  59   $$(if $$(call strneq,UNDEFINED,$$($$(var))),, \
  60         $$(call Set,$$(var),)))
  61
  62 # Collect all subdirectory variables for subsequent use.
  63 $$(foreach var,$(RequiredSubdirVariables) $(OptionalSubdirVariables),\
  64   $$(call Set,$(DirKey).$$(var),$$($$(var))))
  65
  66 # Recurse.
  67 include make/subdir.mk
  68
  69 # Restore directory variable, for cleanliness.
  70 $$(call Set,Dir,$(1))
  71
  72 ifneq ($(DEBUGMAKE),)
  73   $$(info MAKE: $$(Dir): Done processing subdirectory)
  74 endif
  75 endef
  76
  77 # Evaluate this now so we do not have to worry about order of evaluation.
  78
  79 SubDirsList := $(strip \
  80   $(if $(call streq,.,$(Dir)),\
  81        $(SubDirs),\
  82        $(SubDirs:%=$(Dir)/%)))
  83 ifeq ($(SubDirsList),)
  84 else
  85   ifneq ($(DEBUGMAKE),)
  86     $(info MAKE: Descending into subdirs: $(SubDirsList))
  87   endif
  88
  89   $(foreach subdir,$(SubDirsList),\
  90         $(eval $(call subdir_traverse_template,$(subdir))))
  91 endif