support multi-distribution setup

Based on patch by Alexander Wirt, thanks!

scripts/build-and-provide-package

@@ -80,14 +80,20 @@ build_info() {
 identify_sourcefile() {
   if [ -n "${sources:-}" ]; then
     echo "*** Variable \$sources set. Consider switching to ArtifactDeployer plugin setup. ***"
-    sourcefile=$(echo "${sources}/"*.dsc)
+    if [ -z "${distribution:-}" ]; then
+        sourcefile=$(echo "${sources}/"*.dsc)
+    else
+        sourcefile=$(echo "${sources}/distribution=${distribution}/"*.dsc)
+    fi
+
     if [ "$sourcefile" = 'sources/*.dsc' ] ; then
       bailout 1 "Error: no sourcefile (*.dsc) found. Exiting."
     fi
+
     case "$sourcefile" in
       *\ *) echo "*** Multiple source files (*.dsc) present in $(pwd): ***"
-	  ls -la "${sources}/"
-	  bailout 1 "Error: Please re-run source job to force clean rebuild."
+        ls -la "${sources}/"
+        bailout 1 "Error: Please re-run source job to force clean rebuild."
         ;;
     esac
     p="$(basename $sourcefile .dsc)"
@@ -96,7 +102,14 @@ identify_sourcefile() {
     sources="unset"
     echo "*** Identifying newest package version ***"
     newest_version="0"
-    for file in "${JENKINS_HOME}/userContent/${PACKAGE}-source/"*.dsc ; do
+
+    if [ -z "$distribution:-}" ]; then
+      local bpath="${JENKINS_HOME}/userContent/${PACKAGE}-source/"
+    else
+      local bpath="${JENKINS_HOME}/userContent/${PACKAGE}-source/distribution=${distribution}/"
+    fi
+
+    for file in "${bpath}"/*.dsc; do
       SOURCE_PACKAGE="$(awk '/^Source: / {print $2}' $file)"
       p="$(basename $file .dsc)"
       if [ "$p" = '*' ] ; then
@@ -109,8 +122,9 @@ identify_sourcefile() {
         base_version="${cur_version}"
       fi
     done
+
     echo "*** Found package version $newest_version ***"
-    sourcefile="${JENKINS_HOME}/userContent/${PACKAGE}-source/${SOURCE_PACKAGE}"_*"${newest_version}".dsc
+    sourcefile="${bpath}/${SOURCE_PACKAGE}"_*"${newest_version}".dsc
     #archtype="$(awk '/^Architecture/ {print $2}' ${JENKINS_HOME}/userContent/${PACKAGE}-source/${SOURCE_PACKAGE}_*${newest_version}.dsc)"
   fi