Only build new snapshot if new changes exist.

Check the date of the last build against the official
repo on amsterdam.  If no new changes, don't build.

dist/build-chord.sh

@@ -3,6 +3,8 @@
 BUILDROOT=$1
 PUBLISHROOT=$2
 
+REPO=/home/am9/public-hg/dht.hg
+
 if [ -z "$BUILDROOT" ]; then
     echo "Must specify a build root!" 1>&2
     exit 1
@@ -28,6 +30,14 @@ cd $BUILDROOT
 exec >build-$today.log
 exec 2>&1
 
+t=$(stat -f "%Sm" $PUBLISHROOT)
+if [ $(hg -R $REPO log -d "> $t" | grep -c changeset) -eq 0 ];
+then
+   echo "No new changes since $t"
+   exit 0
+fi
+echo "Re-building with changes since $t"
+
 hg clone /home/am9/public-hg/dht.hg dht
 cd dht
 PKG_CONFIG_PATH=:/usr/local/libdata/pkgconfig:/usr/X11R6/libdata/pkgconfig PATH=/usr/local/gnu-autotools/bin:$PATH export PKG_CONFIG_PATH PATH