recipes-google/true-hitless/true-hitless/true-hitless-initialize.sh

#!/bin/sh
set -eu

# Configuration
# Persistent configuration paths
PERSISTENT_TRUE_HITLESS_CONFIG_DIR="/var/google/true-hitless"
PERSISTENT_SERVICE_LIST_FILE="${PERSISTENT_TRUE_HITLESS_CONFIG_DIR}/true-hitless-service-list.txt"
# Systemd configuration directories
SYSTEMD_RUNTIME_OVERRIDE_DIR="/run/systemd/system"
# Content for block-override.conf
BLOCK_OVERRIDE_CONTENT="# True-hitless block-override configuration
# Blocks True-hitless services from multi-user.target
# Services will only start after one of the postprocessing services completes
[Unit]
# Check for completion flags created by postprocessing scripts
# Using subfolder /run/true-hitless/ for better organization
# The -complete suffix indicates the postprocessing is complete
# Removed After=emmc-available-postprocessing.service to avoid deadlock during install
ConditionPathExists=|/run/true-hitless/emmc-available-postprocessing-complete
ConditionPathExists=|/run/true-hitless/emmc-unavailable-postprocessing-complete"
# Systemd folder paths
SYSTEMD_USR_LIB_DIR="/usr/lib/systemd/system"
SYSTEMD_ETC_DIR="/etc/systemd/system"
# Systemd target configuration
SYSTEMD_DISABLE_FROM_TARGETS="multi-user.target.wants"
SYSTEMD_ENABLE_TO_TARGETS="emmc-available.target.wants"
changes_made=0

################################################################################
# 1. Verify true-hitless package installation and enablement
################################################################################
if [ ! -d "${PERSISTENT_TRUE_HITLESS_CONFIG_DIR}" ]; then
  echo "True-hitless package is not installed (true-hitless directory not found at ${PERSISTENT_TRUE_HITLESS_CONFIG_DIR})" >&2
  exit 0
fi
if [ ! -f "${PERSISTENT_SERVICE_LIST_FILE}" ]; then
  echo "True-hitless is not enabled (true-hitless service list file not found at ${PERSISTENT_SERVICE_LIST_FILE})" >&2
  exit 0
fi
echo "True-hitless is enabled" >&2
echo "Starting true-hitless initialization..." >&2


################################################################################
# 2. Read and parse service list
################################################################################
# Service list file format: One service per line with .service suffix
# Example:
#   phosphor-abc@.service
#   xyz.openbmc_project.abcd@.service
#   my-service.service
# No comments, no empty lines, no extra whitespace
################################################################################
echo "Reading service list from ${PERSISTENT_SERVICE_LIST_FILE}..." >&2
service_list=$(cat "${PERSISTENT_SERVICE_LIST_FILE}")

if [ -z "$service_list" ]; then
  echo "No services found in ${PERSISTENT_SERVICE_LIST_FILE}" >&2
  exit 0
fi
echo "Services to process: $service_list" >&2

################################################################################
# 3. Process each service
################################################################################
# Create target directories if they don't exist
for target in $SYSTEMD_ENABLE_TO_TARGETS; do
  mkdir -p "${SYSTEMD_ETC_DIR}/$target"
done

for service in $service_list; do
  echo "Processing service: ${service}" >&2

  service_override_dir="${SYSTEMD_RUNTIME_OVERRIDE_DIR}/${service}.d"
  mkdir -p "$service_override_dir"

  block_override_file="${service_override_dir}/block-override.conf"
  echo "  Generating block-override.conf" >&2
  echo "$BLOCK_OVERRIDE_CONTENT" > "$block_override_file"

  # Find the service unit file
  service_unit_path="${SYSTEMD_USR_LIB_DIR}/${service}"
  if [ ! -f "$service_unit_path" ]; then
    service_unit_path="${SYSTEMD_ETC_DIR}/${service}"
  fi

  if [ ! -f "$service_unit_path" ]; then
    echo "    Warning: Service unit file not found: ${service}" >&2
    continue
  fi

  case "$service" in
    *@.service)
      echo "  Template service detected, finding instances..." >&2
      instances=$(systemctl list-units --all --no-legend "${service%@.service}@*.service" 2>/dev/null | awk '{print $1}')

      if [ -z "$instances" ]; then
        echo "    No instances found" >&2
        continue
      fi
      ;;
    *)
      echo "  Regular service detected" >&2
      # Treat regular service as a single instance
      instances="$service"
      ;;
  esac

  # Process all services
  for instance in $instances; do
    echo "    Processing instance: $instance" >&2
  done

  changes_made=1
done

# Reload systemd if any changes were made
if [ "$changes_made" -eq 1 ]; then
  echo "Reloading systemd daemon..." >&2
  systemctl daemon-reload
  echo "True-hitless initialization completed successfully" >&2
else
  echo "No services processed" >&2
fi