OpenVoiceOS/buildroot-external/rootfs-overlay/usr/libexec/ovos-zram

#!/bin/sh
# Credits go to: https://github.com/home-assistant/operating-system/
set -e

#### Options ####

TYPE=""
MOUNT=""
DEVICE=""
SIZE=0

#### Parse arguments ####

while [ "$1" != "" ]; do
    key=$1
    case $key in
        -t|--type)
            TYPE=$2
            shift
            ;;
        -s|--size)
            SIZE=$2
            shift
            ;;
        -m|--mount)
            MOUNT=$2
            shift
            ;;
        *)
            echo "[Error] $0 : Argument '$1' unknown"
            exit 1
            ;;
    esac
    shift
done

# Valide Type
if [ "$TYPE" != "swap" ] && [ "$TYPE" != "fs" ]; then
    echo "[Error] Type unknown!"
    exit 1
fi

# Lookup device
if [ "$TYPE" = "swap" ]; then
    DEVICE="/dev/zram0"
elif [ "$MOUNT" = "var" ]; then
    DEVICE="/dev/zram1"
#elif [ "$MOUNT" = "tmp" ]; then
#    DEVICE="/dev/zram1"
else
    echo "[Error] No device for lookup!"
    exit 1
fi

# Calc 20% of memory for ZRAM swap partition
if [ "$TYPE" = "swap" ] && [ "$SIZE" -eq "0" ]; then
    SIZE="$(awk '/MemTotal/{ print $2 * 0.20 }' /proc/meminfo)K"
fi

# Init device
zramctl "$DEVICE" -s "$SIZE" -a lz4

# Swap
if [ "$TYPE" = "swap" ]; then
    mkswap -L "ovos-zramswap" "$DEVICE"
fi

# FileSystem
if [ "$TYPE" = "fs" ]; then
    mkfs.ext4 -L "ovos-$MOUNT" -O ^has_journal "$DEVICE"
fi

# Copy persistent file structures into zram device
if [ "$MOUNT" = "var" ]; then
    # Check if this is a first run
    if [ ! -d /mnt/data/var ]; then
        mkdir -p /mnt/data/var
        cp -af /var/* /mnt/data/var/
    fi
    cp -af /mnt/data/var/* "$DEVICE"
fi