include/prereq.mk

   1 #
   2 # Copyright (C) 2006 OpenWrt.org
   3 #
   4 # This is free software, licensed under the GNU General Public License v2.
   5 # See /LICENSE for more information.
   6 #
   7
   8 $(TMP_DIR):
   9         mkdir -p $@
  10
  11 prereq:
  12         if [ -f $(TMP_DIR)/.prereq-error ]; then \
  13                 echo; \
  14                 cat $(TMP_DIR)/.prereq-error; \
  15                 echo; \
  16                 rm -rf $(TMP_DIR); \
  17                 false; \
  18         fi
  19         rm -rf $(TMP_DIR)
  20         mkdir -p $(TMP_DIR)
  21
  22 .SILENT: $(TMP_DIR) prereq
  23
  24 define Require
  25   export PREREQ_CHECK=1
  26   ifeq ($$(CHECK_$(1)),)
  27     prereq: prereq-$(1)
  28
  29     prereq-$(1): $(TMP_DIR) FORCE
  30                 echo -n "Checking '$(1)'... "
  31                 if $(NO_TRACE_MAKE) -f $(firstword $(MAKEFILE_LIST)) check-$(1) >/dev/null 2>/dev/null; then \
  32                         echo 'ok.'; \
  33                 else \
  34                         echo 'failed.'; \
  35                         echo -e "$(strip $(2))" >> $(TMP_DIR)/.prereq-error; \
  36                 fi
  37
  38     check-$(1): FORCE
  39           $(call Require/$(1))
  40     CHECK_$(1):=1
  41
  42     .SILENT: prereq-$(1) check-$(1)
  43   endif
  44 endef
  45
  46
  47 define RequireCommand
  48   define Require/$(1)
  49     which $(1)
  50   endef
  51
  52   $$(eval $$(call Require,$(1),$(2)))
  53 endef
  54