Added PrivateBuildHeaders and UsePrivateBuildHeaders rules.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42163 a95241bf-73f2-0310-859d-f6bbb57e9c96

build/jam/HeadersRules

@@ -160,6 +160,22 @@ rule PrivateHeaders
 }
 
 
+rule PrivateBuildHeaders
+{
+	# PrivateBuildHeaders <group list>
+	#
+	# Returns the directory names for the private build header dirs identified
+	# by <group list>.
+
+	local list = $(1) ;
+	local dirs ;
+	for i in $(list) {
+		dirs += [ FDirName $(HAIKU_TOP) headers build private $(i) ] ;
+	}
+	return $(dirs) ;
+}
+
+
 rule LibraryHeaders
 {
 	# LibraryHeaders <group list>
@@ -273,6 +289,23 @@ rule UsePrivateObjectHeaders
 }
 
 
+rule UsePrivateBuildHeaders
+{
+	# UsePrivateBuildHeaders <group list> [ : <system> ] ;
+	#
+	# Adds the private build C header dirs given by <group list> to the header
+	# search dirs of the subdirectory.
+	# <system> specifies whether to add the dirs as system or local header
+	# search dirs. Defaults to "true".
+	# NOTE: This rule must be invoked *before* the rule that builds the objects.
+
+	local system = $(2) ;
+	system ?= true ;
+
+	UseHeaders [ PrivateBuildHeaders $(1) ] : $(system) ;
+}
+
+
 rule UseCppUnitHeaders
 {
 	SubDirSysHdrs [ FDirName $(HAIKU_TOP) headers tools cppunit ] ;