git-mirror.sh

#!/bin/sh

# Copyright (C) 2019 Tyler Szabo
# This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
# See <http://www.gnu.org/licenses/>.

# Copy to a directory in your PATH and rename to git-mirror (without an extensions)

USAGE='[-f] [--from=<remote-name>] <repo> [<dir>]'
LONG_USAGE=''

NONGIT_OK=1
. "$(git --exec-path)/git-sh-setup"

[ -n "$GIT_DIR" ] && die "fatal: GIT_DIR is set"
git rev-parse --git-dir &>/dev/null && die "fatal: inside a git repo"

if [ "$1" == "help" ] ; then
  git mirror -h
  exit
fi

copied_from="copied-from"

while test $# != 0 ; do
  case "$1" in
  -f)
    force=1
    ;;
  --from=*)
    copied_from=${1#--from=}
    ;;
  --)
    shift
    if [ -z "$source_repo" ] ; then
      source_repo=$1
      shift
    fi
    if [ -z "$target" ] ; then
      target=$1
    fi
    break
    ;;
  -*)
    usage
    ;;
  *)
    if [ -z "$source_repo" ] ; then
      source_repo=$1
    elif [ -z "$target" ] ; then
      target=$1
    else
      usage
    fi
    ;;
  esac
  shift
done

[ -z "$source_repo" ] && usage
[ -z "$copied_from" ] && usage

if [ -z "$target" ] ; then
  target=`basename $source_repo`
  case "$target" in
  *.git)
    ;;
  *)
    target="$target.git" ;;
  esac
fi

if [ -e "$target" ] ; then
  die "fatal: $target already exists"
fi

[ -z $force ] && git -C "$source_repo" config --get-regexp "^remote\.$copied_from\." 2>/dev/null && die "fatal: already copied, pass -f to overwrite \"remote.$copied_from\" configs or set --from="

say "Cloning into '$target' (with custom mirror)..." >&2
mkdir -p "$target"
git -C "$target" init --bare >/dev/null
git -C "$target" remote add --mirror=fetch "$copied_from" "$source_repo"
git -C "$source_repo" config --get-regexp "^(remote|branch)\." | while read name value ; do
  case $name in
  remote.$copied_from.*)
    ;;
  *)
    git -C "$target" config --local --add "$name" "$value"
    ;;
  esac
done
git -C "$target" fetch --quiet "$copied_from"
git -C "$target" fetch --quiet --progress --all
say "done." >&2