#!/bin/bash

# Create a group
# param:
# - type(s) (cpu, memory)
# - group path
function mycg_create {
    GRP=$(id -g -n)
    cgcreate -t $USER:$GRP -a $USER:$GRP -g "$1":"$2"
}

# Format a group path for the current session of the current user
# param: group name
function mycg_path {
    echo -n user/$UID.user/"$XDG_SESSION_ID".session/"$1"
}

# Initialize my groups
function mycg_init {
    echo Init cgroups: $(mycg_path)
    DARKTABLE=$(mycg_path darktable)
    mycg_create "cpu,memory" "$DARKTABLE"
   
    # Limit a bit the memory for darktables
    echo $((1500*1024*1024)) > /sys/fs/cgroup/memory/"$DARKTABLE"/memory.limit_in_bytes
    echo 900 > /sys/fs/cgroup/cpu/"$DARKTABLE"/cpu.shares
    
    # A group for Firefox
    GOOGLEFOX=$(mycg_path googlefox)
    mycg_create "cpu,memory" "$GOOGLEFOX"
    
    echo $((800*1024*1024)) > /sys/fs/cgroup/memory/"$GOOGLEFOX"/memory.limit_in_bytes
    echo 500 > /sys/fs/cgroup/cpu/"$GOOGLEFOX"/cpu.shares
}

if [ "$1" == "init" ]
then
    mycg_init
elif [ "$1" == "run" ]
then
    shift
    if [ "$#" -lt 2 ]
    then
        echo "Error: not enough args"
        echo "mygroup exec PROFILE_NAME COMMAND"
        exit 1
    fi
    CG_GRP="$1"
    shift 
    echo "Execute: group=$CG_GRP, command=$@"
    CG_PATH=$(mycg_path "$CG_GRP")
    cgexec -g memory,cpu:"$CG_PATH" "$@"
else
    echo "Unknown command: $1"
    exit 2
fi