config/makefiles/autotargets.mk

   1 # -*- makefile -*-
   2 # vim:set ts=8 sw=8 sts=8 noet:
   3 #
   4 # This Source Code Form is subject to the terms of the Mozilla Public
   5 # License, v. 2.0. If a copy of the MPL was not distributed with this file,
   6 # You can obtain one at http://mozilla.org/MPL/2.0/.
   7 #
   8
   9 ifndef INCLUDED_AUTOTARGETS_MK #{
  10
  11 # Conditional does not wrap the entire file so multiple
  12 # includes will be able to accumulate dependencies.
  13
  14 ###########################################################################
  15 #      AUTO_DEPS - A list of deps/targets drived from other macros.
  16 ###########################################################################
  17
  18 MKDIR ?= mkdir -p
  19 TOUCH ?= touch
  20
  21 # declare for local use, rules.mk may not have been loaded
  22 space = $(NULL) $(NULL)
  23
  24 # Deps will be considered intermediate when used as a pre-requisite for
  25 # wildcard targets.  Inhibit their removal, mkdir -p is a standalone op.
  26 .PRECIOUS: %/.mkdir.done
  27
  28 #########################
  29 ##---]  FUNCTIONS  [---##
  30 #########################
  31
  32 # Squeeze can be overzealous, restore root for abspath
  33 getPathPrefix =$(if $(filter /%,$(1)),/)
  34
  35 # Squeeze '//' from the path, easily created by string functions
  36 _slashSqueeze =$(foreach val,$(getargv),$(call getPathPrefix,$(val))$(subst $(space),/,$(strip $(subst /,$(space),$(val)))))
  37
  38 # Squeeze extraneous directory slashes from the path
  39 #  o protect embedded spaces within the path
  40 #  o replace //+ sequences with /
  41 slash_strip = \
  42   $(strip \
  43     $(subst <--[**]-->,$(space),\
  44         $(call _slashSqueeze,\
  45     $(subst $(space),<--[**]-->,$(1))\
  46   )))
  47
  48 # Extract directory path from a dependency file.
  49 mkdir_stem =$(foreach val,$(getargv),$(subst /.mkdir.done,$(NULL),$(val)))
  50
  51 ## Generate timestamp file for threadsafe directory creation
  52 mkdir_deps =$(foreach dir,$(getargv),$(call slash_strip,$(dir)/.mkdir.done))
  53
  54 #######################
  55 ##---]  TARGETS  [---##
  56 #######################
  57
  58 %/.mkdir.done: # mkdir -p -p => mkdir -p
  59         $(subst $(space)-p,$(null),$(MKDIR)) -p '$(dir $@)'
  60 # Make the timestamp old enough for not being a problem with symbolic links
  61 # targets depending on it. Use Jan 3, 1980 to accomodate any timezone where
  62 # 198001010000 would translate to something older than FAT epoch.
  63         @$(TOUCH) -t 198001030000 '$@'
  64
  65 # A handful of makefiles are attempting "mkdir dot".
  66 # tbpl/valgrind builds are using this target
  67 # https://bugzilla.mozilla.org/show_bug.cgi?id=837754
  68 .mkdir.done:
  69         @echo 'WARNING: $(MKDIR) -dot- requested by $(MAKE) -C $(CURDIR) $(MAKECMDGOALS)'
  70         @$(TOUCH) -t 198001030000 '$@'
  71
  72 INCLUDED_AUTOTARGETS_MK = 1
  73 endif #}
  74
  75
  76 ## Accumulate deps and cleanup
  77 ifneq (,$(GENERATED_DIRS))
  78   GENERATED_DIRS := $(strip $(sort $(GENERATED_DIRS)))
  79   tmpauto :=$(call mkdir_deps,GENERATED_DIRS)
  80   GENERATED_DIRS_DEPS +=$(tmpauto)
  81 endif
  82
  83 #################################################################
  84 # One ring/dep to rule them all:
  85 #   config/rules.mk::all target is available by default
  86 #   Add $(AUTO_DEPS) as an explicit target dependency when needed.
  87 #################################################################
  88
  89 AUTO_DEPS +=$(GENERATED_DIRS_DEPS)
  90 AUTO_DEPS := $(strip $(sort $(AUTO_DEPS)))
  91
  92 # Complain loudly if deps have not loaded so getargv != $(NULL)
  93 $(call requiredfunction,getargv)