Allow comments in users.conf

entrypoint

@@ -14,6 +14,7 @@ reGid='[[:digit:]]*'
 reDir='[^:]*'
 reArgs="^($reUser)(:$rePass)(:e)?(:$reUid)?(:$reGid)?(:$reDir)?$"
 reArgsMaybe="^[^:[:space:]]+:.*$" # Smallest indication of attempt to use argument
+reArgSkip='^([[:blank:]]*#.*|[[:blank:]]*)$' # comment or empty line
 
 function log() {
     echo "[entrypoint] $@"
@@ -126,7 +127,7 @@ if [ ! -f "$userConfFinalPath" ]; then
 
     # Append mounted config to final config
     if [ -f "$userConfPath" ]; then
-        cat "$userConfPath" | grep -v -e '^$' > "$userConfFinalPath"
+        cat "$userConfPath" | grep -v -E "$reArgSkip" > "$userConfFinalPath"
     fi
 
     # Append users from STDIN to final config

tests/run

@@ -44,6 +44,10 @@ function beforeTest() {
     mkdir "$tmpDir"
 
     echo "test::$(id -u):$(id -g):dir1,dir2" >> "$tmpDir/users"
+    echo "" >> "$tmpDir/users" # empty line
+    echo "# comments are allowed" >> "$tmpDir/users"
+    echo "  " >> "$tmpDir/users" # only whitespace
+    echo "  # with whitespace in front" >> "$tmpDir/users"
     echo "user.with.dot::$(id -u):$(id -g)" >> "$tmpDir/users"
     $sudo docker run \
         -v "$tmpDir/users:/etc/sftp/users.conf:ro" \