Allow explicitly-set git hash in version info.

From: Aaron Kimball <aaron@cloudera.com>

git-svn-id: https://svn.apache.org/repos/asf/incubator/sqoop/trunk@1149926 13f79535-47bb-0310-9956-ffa450edef68

build.xml

@@ -32,7 +32,8 @@
   <property name="Name" value="Sqoop" />
   <property name="version" value="1.1.0-SNAPSHOT" />
   <property name="artifact.name" value="${name}-${version}" />
-  <property name="dest.jar" value="${artifact.name}.jar"/>
+  <property name="dest.jar" value="${artifact.name}.jar" />
+  <property name="git.hash" value="" />
   
   <!-- locations in the source tree -->
   <property name="base.src.dir" location="${basedir}/src" />
@@ -252,6 +253,7 @@
         dir="${basedir}" failonerror="true">
       <arg value="${build.dir}" />
       <arg value="${version}" />
+      <arg value="${git.hash}" />
     </exec>
   </target>
   

src/scripts/write-version-info.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 #
 # Licensed to Cloudera, Inc. under one or more
 # contributor license agreements.  See the NOTICE file distributed with
@@ -21,16 +21,22 @@
 # Arguments are:
 #    path to the root of the build directory
 #    the version number
+#    the git hash of the current checkout. If empty, auto-detect.
 #
 # e.g., $ write-version-info.sh ./build/ 1.0.0
 
 buildroot=$1
 version=$2
+specifiedgithash=$3
 
 outputdir=${buildroot}/src/com.cloudera.sqoop
 outputfile=${outputdir}/SqoopVersion.java
 
-signature=`git log -1 --pretty=format:%H`
+signature=$specifiedgithash
+if [ -z "$signature" ]; then
+  signature=`git log -1 --pretty=format:%H`
+fi
+
 host=`hostname`
 compiledate=`date`