gitで差分ファイルを抽出する ref: http://qiita.com/kaminaly/items/28f9cb4e680deb700833

file0.txt

git archive --format=zip --prefix=root/ HEAD `git diff --diff-filter=d --name-only HEAD^ HEAD` -o archive.zip

file1.txt

function git_diff_archive() 
{
  local diff=""
  local h="HEAD"
  if [ $# -eq 1 ]; then
    if expr "$1" : '[0-9]*$' > /dev/null ; then
      diff="HEAD~${1} HEAD"
    else
      diff="${1} HEAD"
    fi
  elif [ $# -eq 2 ]; then
    diff="${2} ${1}"
    h=$1
  fi
  if [ "$diff" != "" ]; then
    diff="git diff --diff-filter=d --name-only ${diff}"
  fi
  git archive --format=zip --prefix=root/ $h `eval $diff` -o archive.zip
}

file2.txt

git_diff_archive

file3.txt

git_diff_archive 数値

file4.txt

git_diff_archive コミット識別子

file5.txt

git_diff_archive コミット識別子1 コミット識別子2