[SHELL] Print stacktrace

stacktrace.sh

# Original: https://gist.github.com/akostadinov/33bb2606afe1b334169dfbf202991d36
# The difference is that this func outputs stacktrace in reverse order (from top level to lower ones)
function print_stacktrace () {
     STACK=""
     local i
     local stack_size=${#FUNCNAME[@]}
     echo "Stacktrace:"
     # skip this function and "MAIN non_file_source:0"
     for (( i=$stack_size-1; i>=1; i-- )); do
         local func="${FUNCNAME[$i]}"
         [ x$func = x ] && func=MAIN
         local linen="${BASH_LINENO[$(( i - 1 ))]}"
         local src="${BASH_SOURCE[$i]}"
         [ x"$src" = x ] && src=non_file_source
         echo -e "\n   at $func $src:$linen"
     done
}