2 files changed, 35 insertions, 14 deletions

diff --git a/bin/build-packages b/bin/build-packages
index 70676d5..c3be5ff 100755
--- a/bin/build-packages
+++ b/bin/build-packages
@@ -110,17 +110,23 @@ while [ ${count} -ne 0 ]; do
         # build successful
           ls -1 *.pkg.tar.xz | \
             xargs -rn1 gpg --detach-sign
-          if ! tar -c *.pkg.tar.xz{,.sig} | \
-            ssh \
-              -i "${master_build_server_identity}" \
-              -p "${master_build_server_port}" \
-              "${master_build_server_user}@${master_build_server}" \
-              'return-assignment' "${package}" "${git_revision}" "${mod_git_revision}" "${repository}"; then
+          tar -c 'package.tar' *.pkg.tar.xz{,.sig}
+          while ! ssh \
+            -i "${master_build_server_identity}" \
+            -p "${master_build_server_port}" \
+            "${master_build_server_user}@${master_build_server}" \
+            'return-assignment' "${package}" "${git_revision}" "${mod_git_revision}" "${repository}" \
+            < 'package.tar'; do
             case $? in
               1)
-                >&2 echo 'I was too slow, the package is outdated. I will continue ...'
+                # 'return-assignment' was running already
+                sleep $[15+$RANDOM%30]
               ;;
               2)
+                >&2 echo 'I was too slow, the package is outdated. I will continue ...'
+                break
+              ;;
+              3)
                 >& echo "'return-assignment' reports a signature error."
                 exit 1
               ;;
@@ -128,7 +134,7 @@ while [ ${count} -ne 0 ]; do
                 >&2 echo "unknown return code $? from 'return-assignment'"
                 exit 1
             esac
-          fi
+          done
           success=true
           break
         fi
@@ -179,7 +185,7 @@ while [ ${count} -ne 0 ]; do
 
     *)
 
-      >&2 echo "ERROR: Unknown exit code $?."
+      >&2 echo "ERROR: Unknown exit code $? from 'get-assignment'."
       exit 1
 
     ;;
diff --git a/bin/return-assignment b/bin/return-assignment
index 3468f49..b8d1bb4 100755
--- a/bin/return-assignment
+++ b/bin/return-assignment
@@ -9,16 +9,31 @@
 
 # exit codes:
 #  0: ok
-#  1: outdated package
-#  2: signature error
+#  1: another instance was already running
+#  2: outdated package
+#  3: signature error
 
 # TODO:
-#  use lock file(s)
+#  use lock file for build list
 #  remove old version(s) of newly compiled packages
 #  check that received archive contains the expected packages
 
 . "${0%/*}/../conf/default.conf"
 
+# Create a lock file and a trap.
+
+exec 9> "${lock_file}"
+if ! flock -n 9; then
+  >&2 echo 'come back (shortly) later - I was running already'
+  exit 1
+fi
+
+function clean_up {
+  rm -f "${lock_file}"
+}
+
+trap clean_up EXIT
+
 if [ "$5" == 'ERROR' ]; then
 # the build failed on the build slave
 
@@ -51,7 +66,7 @@ fi
 
 if ! grep -q "^${1//./\\.} $2 $3 $4\$" "${work_dir}/build-list"; then
   >&2 echo 'Sorry, the sent package is outdated.'
-  exit 1
+  exit 2
 fi
 
 function clean_up {
@@ -78,7 +93,7 @@ signature_errors="$(
 if [ -n "${signature_errors}" ]; then
   >&2 echo 'The following packages lack a signature or vice versa:'
   >&2 echo "${signature_errors}"
-  exit 2
+  exit 3
 fi
 
 # move packages