sgit/sgit-sha

#! /bin/bash

source_file="$1"
[[ ! -f "$source_file" ]] && echo "Usage: sgit-sha FILE

Returns the sha1 value git associates with FILE." && exit 1


# Every object header contains the object type
# followed by the payload byte length terminated 
# with a null byte (\0).
function header() {
    printf "blob $(wc -c $PWD/$source_file | awk '{print $1}')\0"
}

# A blob contains header + payload.
function blob() {
    cat <(header) "$source_file"
}


blob | sha1sum | cut -f1 -d' '