#!/bin/sh

# Copyright 2011 The ChromiumOS Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# This script should be called daily to clean up log files.
# It can also be called with "--no-periodic" directly from an init
# script in which case it will clean up but not rotate.

# This file exists on the DUT, but not outside of a chroot during repo upload.
# shellcheck source=disk_utils.sh
. "/usr/share/cros/disk_utils.sh"

CLEANUP_PAUSED_FILE="/var/lib/cleanup_logs_paused"
NUM_DAYS_TO_PRESERVE=7
MAX_SUBDIR_SIZE=100   # MB
MAX_SUBDIR_FILES=21
# Threshold for additional histogram reporting (in 1KB blocks), 1GB in total.
ENCRYPTED_REBOOT_VAULT="/mnt/stateful_partition/reboot_vault"

# Paths for the CRX cache. Shared with installer/crx-import.conf
UNVALIDATED_CRX_CACHE="${STATEFUL:?}/unencrypted/import_extensions"
VALIDATED_CRX_CACHE=/var/cache/external_cache

# Remove older files, keep deleting until the directory is less than 100MB
# or only one day old files remains.  ...and also delete older files if
# there are too many (the number of files to keep can optionally be configured
# by $3).
remove_old_files() {
  local subdir="$1"
  local file_pattern="$2"
  local mtime="${NUM_DAYS_TO_PRESERVE}"
  local max_subdir_files="${3:-${MAX_SUBDIR_FILES}}"
  if [ ! -d "${subdir}" ]; then
    return
  fi
  while [ "${mtime}" -ge 1 ]; do
    find "${subdir}" -type f -name "${file_pattern}" -mtime "+${mtime}" -delete
    if [ "$(du -s --block-size=1M "${subdir}" | cut -f 1)" -gt \
         "${MAX_SUBDIR_SIZE}" ]; then
      : "$(( mtime -= 1 ))"
    else
      break
    fi
  done

  # Delete all but the most recent $max_subdir_files files.
  #
  # Note that 'ls -t' doesn't have a "null terminated" mode apparently
  # because you're not supposed to use it for scripts, so we end up
  # using several steps.
  find "${subdir}" -type f -name "${file_pattern}" -printf "%T+ %p\0" | \
    sort -zr | \
    cut -z -d ' ' -f 2- | \
    tail -z "-n+$(( max_subdir_files + 1 ))" | \
    xargs -r -0 rm
}

# Wipe the unencyrpted CRX cache if it still exists.
wipe_crx_cache() {
  local root_dev
  local removable
  local disk_percent

  # If we are on removable media or we haven't imported the crx cache,
  # don't wipe.
  root_dev="$(basename "$(rootdev -s -d)")"
  removable="$(cat "/sys/block/${root_dev}/removable")" || :
  disk_percent="$(get_stateful_usage_percent)" || :
  [ -z "${disk_percent}" ] && disk_percent=0
  if [ "${removable:-0}" -eq 0 ] && [ -d "${UNVALIDATED_CRX_CACHE}" ] && \
      [ -f "${VALIDATED_CRX_CACHE}/.initialized" ] && \
      [ "${disk_percent}" -gt 25 ]; then
    echo "Wiping unvalidated crx cache as it has already been imported."
    rm -rf "${UNVALIDATED_CRX_CACHE}"
  fi
}

remove_old_files_encrypted_reboot_vault() {
  find "${ENCRYPTED_REBOOT_VAULT}" -type f -mtime "+${NUM_DAYS_TO_PRESERVE}" \
      -delete
}

remove_old_pattern_log_files() {
  # Remove old biometrics cypto init, daemon, and firmware
  # updater logs
  remove_old_files /var/log/bio_crypto_init "*"
  remove_old_files /var/log/biod "biod.*"
  remove_old_files /var/log/biod "bio_fw_updater.*"

  # Remove old chrome logs (not logged in)
  remove_old_files /var/log/chrome "chrome_*-*"
  # Remove old lacros chrome logs (not logged in)
  remove_old_files /var/log/lacros "lacros_*-*.log"

  # Remove old chrome logs (logged in)
  remove_old_files /home/chronos/user/log "chrome_*-*"
  # Remove old lacros chrome logs (logged in)
  remove_old_files /home/chronos/user/lacros "lacros_*-*.log"

  # Remove old miscellaneous UI logs
  remove_old_files /var/log/ui "ui.*-*"

  # Remove old update engine logs
  remove_old_files /var/log/update_engine "update_engine.*-*"

  # Remove old power manager logs
  remove_old_files /var/log/power_manager "power*"

  # Remove old vmlog logs (written by metrics_daemon)
  remove_old_files /var/log/vmlog "vmlog.*"

  # Remove old modemfwd helper logs
  remove_old_files /var/log/modemfwd "helper_log.*"

  # Remove old modemloggerd logs
  remove_old_files /var/log/modemloggerd "*"
}

usage() {
  echo "usage: $0 [--no-periodic]"
  echo
  echo "Delete old logs and perform periodic tasks like rotating logs."
  echo
  echo "This program always deletes old log files for programs that"
  echo "create one log per boot.  Unless called with --no-periodic"
  echo "it will also do periodic tasks like rotating log files"
  echo "and sending metrics."
}

main() {
  if [ "$#" -eq 1 ] && [ "$1" != "--no-periodic" ] ||
     [ "$#" -gt 1 ]; then
    usage
    return 1
  fi

  if [ -r "${CLEANUP_PAUSED_FILE}" ]; then
    echo "Exiting early because ${CLEANUP_PAUSED_FILE} exists."
    return 0
  fi

  remove_old_pattern_log_files

  # Remove iwlwifi logs older than one hour, since they are large.
  find /var/log -name "last_iwlwifi_dump*" -mmin +60 -delete

  # Remove old files in the encrypted reboot vault.
  remove_old_files_encrypted_reboot_vault

  # Quit if called at init; everything below only happens periodically
  if [ "$1" = "--no-periodic" ]; then
    return 0
  fi

  # Collect log-related metrics before rotation.
  log-metrics-collector

  # Rotate other logs
  log_rotator

  # Report disk usage statistics
  (
    # Subshell to re-use $@ array.
    set -- 0 1073741824 50
    metrics_client Platform.DiskUsageVar \
                  "$(du -sxk /var/ | awk '{print $1}')" "$@"
    metrics_client Platform.DiskUsageChronos \
                  "$(du -sxk /home/chronos | awk '{print $1}')" "$@"
  )

  # Report overall stateful usage.
  metrics_client -e Platform.StatefulUsage "$(get_stateful_usage_percent)" 101

  # Report lifetime writes from the stateful partition in GiBs.
  LIFETIME_WRITES="$(get_stateful_lifetime_writes)"
  metrics_client Platform.StatefulLifetimeWrites \
    "$((LIFETIME_WRITES / 1048576))" 0 16777216 100

  # Report used space from the stateful partition in GBs.
  STATEFUL_USED="$(get_stateful_used_space_blocks 1000)"
  metrics_client Platform.StatefulUsedSpace \
    "$((STATEFUL_USED / 1000000))" 0 16777216 50

  # Report free space from the stateful partition in MBs. Some boards
  # ship with a variety of SSD sizes, so free space metrics can be
  # useful in addition to used space. Record in MB so we have higher
  # precision in the buckets close to zero (out of space). Max out at
  # 2 TB.
  STATEFUL_FREE="$(get_stateful_free_space_blocks 1000)"
  metrics_client Platform.StatefulFreeSpace \
    "$((STATEFUL_FREE / 1000))" 0 2097152 50

  wipe_crx_cache
}
main "$@"