finally move buildroot-ng to trunk
[oweals/openwrt.git] / include / prereq.mk
diff --git a/include/prereq.mk b/include/prereq.mk
new file mode 100644 (file)
index 0000000..eda7ca3
--- /dev/null
@@ -0,0 +1,54 @@
+# 
+# Copyright (C) 2006 OpenWrt.org
+#
+# This is free software, licensed under the GNU General Public License v2.
+# See /LICENSE for more information.
+#
+
+$(TMP_DIR):
+       mkdir -p $@
+
+prereq:
+       if [ -f $(TMP_DIR)/.prereq-error ]; then \
+               echo; \
+               cat $(TMP_DIR)/.prereq-error; \
+               echo; \
+               rm -rf $(TMP_DIR); \
+               false; \
+       fi
+       rm -rf $(TMP_DIR)
+       mkdir -p $(TMP_DIR)
+
+.SILENT: $(TMP_DIR) prereq
+
+define Require
+  export PREREQ_CHECK=1
+  ifeq ($$(CHECK_$(1)),)
+    prereq: prereq-$(1)
+
+    prereq-$(1): $(TMP_DIR) FORCE
+               echo -n "Checking '$(1)'... "
+               if $(NO_TRACE_MAKE) -f $(firstword $(MAKEFILE_LIST)) check-$(1) >/dev/null 2>/dev/null; then \
+                       echo 'ok.'; \
+               else \
+                       echo 'failed.'; \
+                       echo -e "$(strip $(2))" >> $(TMP_DIR)/.prereq-error; \
+               fi
+
+    check-$(1): FORCE
+         $(call Require/$(1))
+    CHECK_$(1):=1
+
+    .SILENT: prereq-$(1) check-$(1)
+  endif
+endef
+
+
+define RequireCommand
+  define Require/$(1)
+    which $(1)
+  endef
+
+  $$(eval $$(call Require,$(1),$(2)))
+endef
+