Fix wait command with supervisord

Author: meyer9

reth/reth-entrypoint

@@ -46,6 +46,24 @@ case "$LOG_LEVEL" in
         ;;
 esac
 
+wait_for_pid() {
+    local pid="$1"
+
+    # Check if the process exists at all before waiting
+    if [[ ! -e "/proc/$pid" ]]; then
+        echo "Process $pid does not exist." >&2
+        return 1
+    fi
+
+    echo "Waiting for process $pid to exit..."
+    while [[ -e "/proc/$pid" ]]; do
+        sleep 1
+    done
+    echo "Process $pid has exited."
+}
+
+
+
 # Add pruning for base
 if [[ "${RETH_PRUNING_ARGS+x}" = x ]]; then
     echo "Adding pruning arguments: $RETH_PRUNING_ARGS"
@@ -71,7 +89,7 @@ if [[ "$RETH_HISTORICAL_PROOFS" == "true" && -n "$RETH_HISTORICAL_PROOFS_STORAGE
     # wait for json-rpc to return a block number greater than 0 (synced beyond genesis)
     while true; do
         RESPONSE=$(curl -s -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getBlockByNumber","params":["latest", false],"id":1}' http://127.0.0.1:"$RPC_PORT" 2>/dev/null || true)
-        
+
         if echo "$RESPONSE" | grep -q '"number":"0x0"'; then
             echo "waiting for reth node to sync beyond genesis block"
         elif echo "$RESPONSE" | grep -q '"result"'; then
@@ -80,7 +98,7 @@ if [[ "$RETH_HISTORICAL_PROOFS" == "true" && -n "$RETH_HISTORICAL_PROOFS_STORAGE
         else
             echo "waiting for reth node to start up"
         fi
-        
+
         sleep 1
         MAX_WAIT=$((MAX_WAIT - 1))
         if [ "$MAX_WAIT" -eq 0 ]; then
@@ -93,7 +111,7 @@ if [[ "$RETH_HISTORICAL_PROOFS" == "true" && -n "$RETH_HISTORICAL_PROOFS_STORAGE
     # shut down gracefully
     kill "$PID"
 
-    (wait "$PID" && echo "reth node initialized") || echo "warning: reth node exited with code $?"
+    (wait_for_pid "$PID" && echo "reth node initialized") || echo "warning: reth node exited with code $?"
 
     ADDITIONAL_ARGS="$ADDITIONAL_ARGS --proofs-history --proofs-history.storage-path=$RETH_HISTORICAL_PROOFS_STORAGE_PATH"