build: allow openwrt.git packages to be replaced by feeds

[openwrt/svn-archive/archive.git] / include / prereq.mk

diff --git a/include/prereq.mk b/include/prereq.mk
index 8a08be8e68c9f4d34b0b8085c99ab01602bd21f5..45ee77e9e6042a9f46af1356ac6a5770dd76ff53 100644 (file)
--- a/include/prereq.mk
+++ b/include/prereq.mk
@@ -1,10 +1,13 @@
 # 
-# Copyright (C) 2006 OpenWrt.org
+# Copyright (C) 2006-2007 OpenWrt.org
 #
 # This is free software, licensed under the GNU General Public License v2.
 # See /LICENSE for more information.
 #
 
+ifneq ($(__prereq_inc),1)
+__prereq_inc:=1
+
 prereq:
        if [ -f $(TMP_DIR)/.prereq-error ]; then \
                echo; \
@@ -15,6 +18,7 @@ prereq:
        fi
 
 .SILENT: prereq
+endif
 
 define Require
   export PREREQ_CHECK=1
@@ -35,6 +39,7 @@ define Require
     CHECK_$(1):=1
 
     .SILENT: prereq-$(1) check-$(1)
+    .NOTPARALLEL:
   endif
 endef
 
@@ -47,3 +52,11 @@ define RequireCommand
   $$(eval $$(call Require,$(1),$(2)))
 endef
 
+define RequireHeader
+  define Require/$(1)
+    [ -e "$(1)" ]
+  endef
+  
+  $$(eval $$(call Require,$(1),$(2)))
+endef
+