Avoid ccache dir being created when not used

Also clean an empty ccache dir.

icinga-build-deb-binary

@@ -17,7 +17,9 @@ fi
 
 # reset ccache statistics
 # so we now the statistics of the new build
-ccache -z # (--zero-stats)
+if [ -d "${CCACHE_DIR}" ]; then
+  ccache -z # (--zero-stats)
+fi
 
 # use eatmydata if present
 eatmydata=
@@ -70,9 +72,17 @@ echo "[ Building binary package ]"
   dpkg-buildpackage -rfakeroot -uc -us $binopts
 )
 
-echo "[ ccache stats ]"
-ccache -s | tee build/ccache-stats.txt # (--show-stats)
-echo
+if [ -d "${CCACHE_DIR}" ]; then
+  cached_files="$(find "${CCACHE_DIR}" -type f ! -name ccache.conf ! -name stats | wc -l)"
+  if [ "$cached_files" -eq 0 ]; then
+    echo "Removing empty ccache dir: ${CCACHE_DIR}"
+    rm -rf "${CCACHE_DIR}"
+  else
+    echo "[ ccache stats ]"
+    ccache -s | tee build/ccache-stats.txt # (--show-stats)
+    echo
+  fi
+fi
 
 echo "[ Running Lintian ]"
 (

icinga-build-rpm-binary

@@ -63,12 +63,13 @@ if command -v ccache &>/dev/null; then
   echo "[ Preparing ccache for our environment ]"
   export CCACHE_DIR="${WORKDIR}/ccache"
   rm -f ccache.stats
-  test -d "${CCACHE_DIR}" || mkdir "${CCACHE_DIR}"
   preconfigure_ccache
 
   # reset ccache statistics
   # so we now the statistics of the new build
-  ccache -z # (--zero-stats)
+  if [ -d "${CCACHE_DIR}" ]; then
+    ccache -z # (--zero-stats)
+  fi
 fi
 
 echo "[ Building binary package ]"
@@ -88,10 +89,16 @@ eval "$(get_rpmbuild --rebuild "${source_rpm}")"
   fi
 )
 
-if command -v ccache &>/dev/null; then
-  echo "[ ccache stats ]"
-  ccache -s | tee build/ccache-stats.txt # (--show-stats)
-  echo
+if command -v ccache &>/dev/null && [ -d "${CCACHE_DIR}" ]; then
+  cached_files="$(find "${CCACHE_DIR}" -type f ! -name ccache.conf ! -name stats | wc -l)"
+  if [ "$cached_files" -eq 0 ]; then
+    echo "Removing empty ccache dir: ${CCACHE_DIR}"
+    rm -rf "${CCACHE_DIR}"
+  else
+    echo "[ ccache stats ]"
+    ccache -s | tee build/ccache-stats.txt # (--show-stats)
+    echo
+  fi
 fi
 
 echo "[ Running rpmlint ]"