git-clone-script

#!/bin/sh
#
# Copyright (c) 2005, Linus Torvalds
# Copyright (c) 2005, Junio C Hamano
# 
# Clone a repository into a different directory that does not yet exist.

usage() {
	echo >&2 "* git clone [-l [-s]] [-q] [-u <upload-pack>] <repo> <dir>"
	exit 1
}

get_repo_base() {
	(cd "$1" && (cd .git ; pwd)) 2> /dev/null
}

quiet=
use_local=no
local_shared=no
upload_pack=
while
	case "$#,$1" in
	0,*) break ;;
	*,-l|*,--l|*,--lo|*,--loc|*,--loca|*,--local) use_local=yes ;;
        *,-s|*,--s|*,--sh|*,--sha|*,--shar|*,--share|*,--shared) 
          local_shared=yes ;;
	*,-q|*,--quiet) quiet=-q ;;
	1,-u|1,--upload-pack) usage ;;
	*,-u|*,--upload-pack)
		shift
		upload_pack="--exec=$1" ;;
	*,-*) usage ;;
	*) break ;;
	esac
do
	shift
done

# Turn the source into an absolute path if
# it is local
repo="$1"
local=no
if base=$(get_repo_base "$repo"); then
	repo="$base"
	local=yes
fi

dir="$2"
mkdir "$dir" &&
D=$(
	(cd "$dir" && git-init-db && pwd)
) &&
test -d "$D" || usage

# We do local magic only when the user tells us to.
case "$local,$use_local" in
yes,yes)
	( cd "$repo/objects" ) || {
		echo >&2 "-l flag seen but $repo is not local."
		exit 1
	}

	case "$local_shared" in
	no)
	    # See if we can hardlink and drop "l" if not.
	    sample_file=$(cd "$repo" && \
			  find objects -type f -print | sed -e 1q)

	    # objects directory should not be empty since we are cloning!
	    test -f "$repo/$sample_file" || exit

	    l=
	    if ln "$repo/$sample_file" "$D/.git/objects/sample" 2>/dev/null
	    then
		    l=l
	    fi &&
	    rm -f "$D/.git/objects/sample" &&
	    cd "$repo" &&
	    find objects -type f -print |
	    cpio -puamd$l "$D/.git/" || exit 1
	    ;;
	yes)
	    mkdir -p "$D/.git/objects/info"
	    echo "$repo/objects" >"$D/.git/objects/info/alternates"
	    ;;
	esac

	# Make a duplicate of refs and HEAD pointer
	HEAD=
	if test -f "$repo/HEAD"
	then
		HEAD=HEAD
	fi
	tar Ccf "$repo" - refs $HEAD | tar Cxf "$D/.git" - || exit 1
	;;
*)
	case "$repo" in
	rsync://*)
		rsync $quiet -avz --ignore-existing "$repo/objects/" "$D/.git/objects/" &&
		rsync $quiet -avz --ignore-existing "$repo/refs/" "$D/.git/refs/"
		;;
	http://*)
		git-clone-dumb-http "$repo" "$D"
		case "$?" in
		2)
			echo "Somebody should define smarter http server protocol" >&2
			exit 1
			;;
		0)
			;;
		*)
			exit
		esac
		;;
	*)
		cd "$D" && case "$upload_pack" in
		'') git-clone-pack $quiet "$repo" ;;
		*) git-clone-pack $quiet "$upload_pack" "$repo" ;;
		esac
		;;
	esac
	;;
esac

# Update origin.
mkdir -p "$D/.git/branches/" &&
rm -f "$D/.git/branches/origin" &&
echo "$repo" >"$D/.git/branches/origin"