utils/ipc-tap: Check if a hook is present before executing it

When ipc-tap calls per-topic hooks, it does not check if a hook was
set, causing an error to be emitted when no hook for a topic was set.

This commit modifies ipc-tap so that it checks if a hook is set before
executing it.

diff --git a/utils/ipc-tap.sh b/utils/ipc-tap.sh
index df49a1364077181a2dde921eab85e3cab9c1f2c6..265c1d9100a9f00ed7d3d63c18d82d837f5688cc 100755 (executable)
--- a/utils/ipc-tap.sh
+++ b/utils/ipc-tap.sh
@@ -67,8 +67,12 @@ invoke_hooks() {
        local message="$2"
 
        local data
+       local hook
+
+       hook="${hooks[$topic]}"
 
-       if data=$("${hooks[$topic]}" <<< "$message") &&
+       if [[ -n "$hook" ]] &&
+          data=$("$hook" <<< "$message") &&
           [[ -n "$data" ]]; then
                output_message "HookData" "$data"
        fi