HADOOP-6267. Permit building contrib modules located in external source trees. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@816752 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -200,6 +200,9 @@ Trunk (unreleased changes)
     This permits one to take advantage of both Avro's RPC versioning
     features and Hadoop's proven RPC scalability.  (cutting)
 
+    HADOOP-6267. Permit building contrib modules located in external
+    source trees.  (Todd Lipcon via cutting)
+
   IMPROVEMENTS
 
     HADOOP-4565. Added CombineFileInputFormat to use data locality information

src/contrib/build-contrib.xml

@@ -22,6 +22,7 @@
 <project name="hadoopbuildcontrib" xmlns:ivy="antlib:org.apache.ivy.ant">
 
   <property name="name" value="${ant.project.name}"/>
+  <dirname property="src.contrib.dir" file="${ant.file.hadoopbuildcontrib}" />
   <property name="root" value="${basedir}"/>
 
   <!-- Load all the default properties, and any the user wants    -->
@@ -29,7 +30,7 @@
   <property file="${user.home}/${name}.build.properties" />
   <property file="${root}/build.properties" />
 
-  <property name="hadoop.root" location="${root}/../../../"/>
+  <property name="hadoop.root" location="${src.contrib.dir}/../../"/>
   <property name="src.dir"  location="${root}/src/java"/>
   <property name="src.test" location="${root}/src/test"/>
   <property name="src.examples" location="${root}/src/examples"/>