#!/bin/sh
set -eu

# Ensure /etc/ntp.conf exists for tools/hooks expecting it
if [ ! -e /etc/ntp.conf ] && [ -f /etc/ntpd.conf ]; then
  ln -sf /etc/ntpd.conf /etc/ntp.conf
fi
# dhcpcd hook may write into /var/lib/ntp
mkdir -p /var/lib/ntp

# Extract ntp=... from kernel cmdline if present
ntp_flags="$(grep -o 'ntp=[^ ]*' /proc/cmdline 2>/dev/null | sed 's/^ntp=//' || true)"

params=""
if [ -n "${ntp_flags}" ]; then
  # Convert comma-separated list into multiple -p args
  params="-p $(printf '%s' "${ntp_flags}" | sed 's/,/ -p /g')"
else
  # Sensible defaults when no ntp= is provided
  params="-p time.google.com -p time1.google.com -p time2.google.com -p time3.google.com"
fi

# BusyBox ntpd uses -p servers on CLI; /etc/ntp.conf symlink above helps alternative daemons.
exec ntpd -n ${params}