mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-11-29 10:23:29 +00:00
cb657d4ad1
As reported by @Evils-Devils in Zygo/bees#123, the bees service wrapper can fail on account of `findmnt` not being able to identify a mounted filesystem using the default (kernel-introspection) mechanism. Fall back to mtab and fstab-based inspection in turn should this fail.
228 lines
8.5 KiB
Bash
Executable File
228 lines
8.5 KiB
Bash
Executable File
#!@bash@/bin/bash
|
|
PATH=@bash@/bin:@coreutils@/bin:@utillinux@/bin:@btrfsProgs@/bin:$PATH
|
|
beesd_bin=@bees@/lib/bees/bees
|
|
# PLEASE KEEP NIX-ISMS ABOVE THIS LINE TO EASE UPSTREAM MERGE
|
|
#!/usr/bin/env bash
|
|
|
|
shopt -s extglob
|
|
|
|
# Upstream wrapper requires UUID to be used for configuration.
|
|
|
|
# However, when declaratively describing a host, we may not know its UUID, and
|
|
# shouldn't need to persist something that will differ between hosts built from
|
|
# the same configuration template.
|
|
|
|
# Thus, for using bees from NixOS, we have our own wrapper, which supports not
|
|
# just UUID but any specification permitted by findmnt
|
|
|
|
[[ $bees_debug ]] && { PS4=':${BASH_SOURCE##*/}:$LINENO+'; set -x; }
|
|
|
|
usage() {
|
|
cat >&2 <<EOF
|
|
Usage: ${BASH_SOURCE##*/} run|cleanup config-name|fsSpec [idxSizeMB=...] [verbosity=...] [workDir=...] [-- daemon-options...]
|
|
|
|
fsSpec should be in a format recognized by findmnt. Alternately,
|
|
"config-name" may refer to a file that exists in ${bees_config_dir:-/etc/bees}
|
|
with a .conf extension; if that file does not specify UUID, findmnt will be
|
|
used in addition.
|
|
|
|
Note that while config files may presently use shell arithmetic, use of this
|
|
functionality is not encouraged going forward: Setting ''idxSizeMB=4096'' is
|
|
preferred over ''DB_SIZE=$((1024*1024*1024*4))'' or ''DB_SIZE=$(( AL16M * 256 ))'',
|
|
although both of these are presently supported.
|
|
|
|
If fsSpec contains a /, it assumed to be a mount point to be looked up by
|
|
findmnt, not a config file name.
|
|
|
|
daemon-options are passed directly through to the daemon on startup, as
|
|
documented at https://github.com/Zygo/bees/blob/master/docs/options.md.
|
|
EOF
|
|
exit 1
|
|
}
|
|
|
|
die() { echo "$*" >&2; exit 1; }
|
|
|
|
allConfigNames=( blockdev fsSpec home idxSize idxSizeMB mntDir runDir status verbosity workDir )
|
|
|
|
# Alternate names for configuration values; "bees_" will always be prepended
|
|
declare -A altConfigNames=(
|
|
# from original bees wrapper
|
|
[BEESHOME]=home
|
|
[BEESSTATUS]=status
|
|
[MNT_DIR]=mntDir
|
|
[UUID]=uuid
|
|
[WORK_DIR]=runDir
|
|
[DB_SIZE]=idxSize
|
|
)
|
|
|
|
# legacy bees config files can be arbitrary shell scripts, so we need to actually evaluate them
|
|
sandboxedConfigFileEval() {
|
|
bash_exe=$(type -P bash) || exit
|
|
PATH=/var/empty ENV='' BASH_ENV='' AL128K="$((128*1024))" AL16M="$((16*1024*1024))" "$bash_exe" -r ${bees_debug+-x} \
|
|
-c 'eval "$(</dev/stdin)" >&2; for var; do [[ ${!var} ]] && printf "%q=%s\\0" "$var" "${!var}"; done' \
|
|
"${!altConfigNames[@]}" "${allConfigNames[@]}" \
|
|
<"$1"
|
|
}
|
|
|
|
readConfigFileIfExists() {
|
|
local line
|
|
[[ -s $1 ]] || return 1
|
|
while IFS= read -r -d '' line; do
|
|
line=${line%%+([[:space:]])"#"*}
|
|
[[ $line ]] || continue
|
|
[[ $line = *=* ]] || {
|
|
printf 'WARNING: Config file line not recognized: %q\n' "$line" >&2
|
|
continue
|
|
}
|
|
set_option "$line"
|
|
done < <(sandboxedConfigFileEval "$1")
|
|
}
|
|
|
|
set_option() {
|
|
local k v
|
|
k="${1%%=*}" v="${1#*=}"
|
|
[[ ${altConfigNames[$k]} ]] && k=${altConfigNames[$k]}
|
|
printf -v "bees_$k" %s "$v"
|
|
}
|
|
|
|
uuid_re='^[[:xdigit:]]{8}-[[:xdigit:]]{4}-[[:xdigit:]]{4}-[[:xdigit:]]{4}-[[:xdigit:]]{12}$'
|
|
|
|
# Shared code for setting configuration used by other operations.
|
|
#
|
|
# Reads from global associative array "opts" containing options passed in as
|
|
# key=value pairs on the command line, looks for config-file overrides, and
|
|
# sets individual global variables.
|
|
_setup() {
|
|
declare fstype
|
|
bees_fsSpec=$1; shift
|
|
|
|
# Look for file-based configuration, additional to honoring configuration on the command line
|
|
bees_config_dir="${bees_config_dir:-/etc/bees}"
|
|
if [[ $bees_fsSpec =~ $uuid_re ]]; then
|
|
bees_uuid=$bees_fsSpec
|
|
# If our spec looks like a bare UUID, and no config file exists in the new
|
|
# format, fall back to legacy config file search mechanism (grep; ewww).
|
|
if ! readConfigFileIfExists "$bees_config_dir/UUID=$bees_fsSpec.conf"; then
|
|
# Legacy approach to finding a config file: Grep for a *.conf file
|
|
# containing the UUID within its text. Permitting spaces around the "="
|
|
# appears to be a bug, but is retained for compatibility with the
|
|
# original upstream script.
|
|
allConfFiles=( "$bees_config_dir"/*.conf )
|
|
if (( ${#allConfFiles[@]} )); then
|
|
# in read or readarray with -d '', the NUL terminating the empty string is used as delimiter character.
|
|
readarray -d '' -t matchingConfFiles < <(grep -E -l -Z "^[^#]*UUID[[:space:]]*=[[:space:]]*" "${allConfFiles[@]}")
|
|
else
|
|
matchingConfFiles=( )
|
|
fi
|
|
if (( ${#matchingConfFiles[@]} == 1 )); then
|
|
# Exactly one configuration file exists in our target directory with a reference to the UUID given.
|
|
bees_config_file=${matchingConfFiles[0]}
|
|
readConfigFileIfExists "$bees_config_file"
|
|
echo "NOTE: Please consider renaming $bees_config_file to $bees_config_dir/UUID=$bees_fsSpec" >&2
|
|
echo " ...and passing UUID=$bees_fsSpec on startup." >&2
|
|
elif (( ${#matchingConfFiles[@]} > 1 )); then
|
|
# The legacy wrapper would silently use the first file and ignore
|
|
# others, but... no.
|
|
echo "ERROR: Passed a bare UUID, but multiple configuration files match it:" >&2
|
|
printf ' - %q\n' "${matchingConfFiles[@]}" >&2
|
|
die "Unable to continue."
|
|
fi
|
|
fi
|
|
else
|
|
# For a non-UUID fsSpec that is not a path, look only for a config file
|
|
# exactly matching its text.
|
|
#
|
|
# (Passing a mount point as a fsSpec is only supported with the new
|
|
# wrapper; all key=value pairs can be passed on the command line in this
|
|
# mode, so config file support is not needed).
|
|
[[ $bees_fsSpec = */* ]] || readConfigFileIfExists "$bees_config_dir/$bees_fsSpec.conf"
|
|
fi
|
|
|
|
[[ $bees_uuid ]] || {
|
|
# if bees_uuid is not in our .conf file, look it up with findmnt
|
|
for findmnt_mode in --kernel --mtab --fstab; do
|
|
read -r bees_uuid fstype < <(findmnt "$findmnt_mode" -n -o uuid,fstype "$bees_fsSpec") ||:
|
|
[[ $bees_uuid && $fstype ]] && break
|
|
done
|
|
[[ $bees_uuid ]] || die "Unable to identify a device matching $bees_fsSpec with findmnt"
|
|
[[ $fstype = btrfs ]] || die "Device type is $fstype, not btrfs"
|
|
}
|
|
|
|
[[ $bees_uuid = */* ]] || readConfigFileIfExists "$bees_config_dir/UUID=$bees_uuid.conf"
|
|
|
|
# Honor any values read from config files above; otherwise, set defaults.
|
|
bees_workDir="${bees_workDir:-.beeshome}"
|
|
bees_runDir="${bees_runDir:-/run/bees}"
|
|
bees_mntDir="${bees_mntDir:-$bees_runDir/mnt/$bees_uuid}"
|
|
bees_home="${bees_home:-$bees_mntDir/$bees_workDir}"
|
|
bees_status="${bees_status:-${bees_runDir}/$bees_uuid.status}"
|
|
bees_verbosity="${bees_verbosity:-6}"
|
|
bees_idxSizeMB="${bees_idxSizeMB:-1024}"
|
|
bees_idxSize=${bees_idxSize:-"$(( bees_idxSizeMB * 1024 * 1024 ))"}
|
|
bees_blockdev=${bees_blockdev:-"/dev/disk/by-uuid/$bees_uuid"}
|
|
|
|
[[ -b $bees_blockdev ]] || die "Block device $bees_blockdev missing"
|
|
(( bees_idxSize % (16 * 1024 * 1024) == 0 )) || die "DB size must be divisible by 16MB"
|
|
}
|
|
|
|
do_run() {
|
|
local db old_db_size
|
|
|
|
_setup "$1"; shift
|
|
mkdir -p -- "$bees_mntDir" || exit
|
|
|
|
# subvol id 5 is reserved for the root subvolume of a btrfs filesystem.
|
|
mountpoint -q "$bees_mntDir" || mount -osubvolid=5 -- "$bees_blockdev" "$bees_mntDir" || exit
|
|
if [[ -d $bees_home ]]; then
|
|
btrfs subvolume show "$bees_home" >/dev/null 2>&1 || die "$bees_home exists but is not a subvolume"
|
|
else
|
|
btrfs subvolume create "$bees_home" || exit
|
|
sync # workaround for Zygo/bees#93
|
|
fi
|
|
db=$bees_home/beeshash.dat
|
|
touch -- "$db"
|
|
|
|
old_db_size=$(stat -c %s -- "$db")
|
|
new_db_size=$bees_idxSize
|
|
|
|
if (( old_db_size != new_db_size )); then
|
|
rm -f -- "$bees_home"/beescrawl."$bees_uuid".dat
|
|
truncate -s "$new_db_size" -- "$db" || exit
|
|
fi
|
|
chmod 700 -- "$bees_home"
|
|
|
|
# BEESSTATUS and BEESHOME are the only variables handled by the legacy
|
|
# wrapper for which getenv() is called in C code.
|
|
BEESSTATUS=$bees_status BEESHOME=$bees_home exec "${beesd_bin:-/lib/bees/bees}" \
|
|
--verbose "$bees_verbosity" \
|
|
"$@" "$bees_mntDir" || exit
|
|
}
|
|
|
|
do_cleanup() {
|
|
_setup "$1"; shift
|
|
mountpoint -q "$bees_mntDir" && umount -l -- "$bees_mntDir" || exit
|
|
}
|
|
|
|
(( $# >= 2 )) || usage
|
|
declare -f "do_$1" >/dev/null 2>&1 || usage
|
|
mode=$1; shift # must be a do_* function; currently "run" or "cleanup"
|
|
|
|
declare -a args=( "$1" ); shift # pass first argument (config-name|fsSpec) through literally
|
|
|
|
# parse other arguments as key=value pairs, or pass them through literally if they do not match that form.
|
|
# similarly, any option after "--" will be passed through literally.
|
|
while (( $# )); do
|
|
if [[ $1 = *=* ]]; then
|
|
set_option "$1"
|
|
elif [[ $1 = -- ]]; then
|
|
shift
|
|
args+=( "$@" )
|
|
break
|
|
else
|
|
args+=( "$1" )
|
|
fi
|
|
shift
|
|
done
|
|
|
|
"do_$mode" "${args[@]}"
|