git-fetch.sh - jrn/git - Git at Google

 #!/bin/sh
 #

 USAGE='<fetch-options> <repository> <refspec>...'
 SUBDIRECTORY_OK=Yes
 . git-sh-setup
 set_reflog_action "fetch $*"
 cd_to_toplevel ;# probably unnecessary...

 . git-parse-remote
 _x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
 _x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"

 LF='
 '
 IFS="$LF"

 no_tags=
 tags=
 append=
 force=
 verbose=
 update_head_ok=
 exec=
 upload_pack=
 keep=
 shallow_depth=
 while case "$#" in 0) break ;; esac
 do
 	case "$1" in
 	-a|--a|--ap|--app|--appe|--appen|--append)
 		append=t
 		;;
 	--upl|--uplo|--uploa|--upload|--upload-|--upload-p|\
 	--upload-pa|--upload-pac|--upload-pack)
 		shift
 		exec="--exec=$1"
 		upload_pack="-u $1"
 		;;
 	-f|--f|--fo|--for|--forc|--force)
 		force=t
 		;;
 	-t|--t|--ta|--tag|--tags)
 		tags=t
 		;;
 	-n|--n|--no|--no-|--no-t|--no-ta|--no-tag|--no-tags)
 		no_tags=t
 		;;
 	-u|--u|--up|--upd|--upda|--updat|--update|--update-|--update-h|\
 	--update-he|--update-hea|--update-head|--update-head-|\
 	--update-head-o|--update-head-ok)
 		update_head_ok=t
 		;;
 	-v|--verbose)
 		verbose=Yes
 		;;
 	-k|--k|--ke|--kee|--keep)
 		keep='-k -k'
 		;;
 	--depth=*)
 		shallow_depth="--depth=`expr "z$1" : 'z-[^=]*=\(.*\)'`"
 		;;
 	--depth)
 		shift
 		shallow_depth="--depth=$1"
 		;;
 	-*)
 		usage
 		;;
 	*)
 		break
 		;;
 	esac
 	shift
 done

 case "$#" in
 0)
 	origin=$(get_default_remote)
 	test -n "$(get_remote_url ${origin})" ||
 		die "Where do you want to fetch from today?"
 	set x $origin ; shift ;;
 esac

 remote_nick="$1"
 remote=$(get_remote_url "$@")
 refs=
 rref=
 rsync_slurped_objects=

 if test "" = "$append"
 then
 	: >"$GIT_DIR/FETCH_HEAD"
 fi

 # Global that is reused later
 ls_remote_result=$(git ls-remote $upload_pack "$remote") ||
 	die "Cannot get the repository state from $remote"

 append_fetch_head () {
     head_="$1"
     remote_="$2"
     remote_name_="$3"
     remote_nick_="$4"
     local_name_="$5"
     case "$6" in
     t) not_for_merge_='not-for-merge' ;;
     '') not_for_merge_= ;;
     esac

     # remote-nick is the URL given on the command line (or a shorthand)
     # remote-name is the $GIT_DIR relative refs/ path we computed
     # for this refspec.

     # the $note_ variable will be fed to git-fmt-merge-msg for further
     # processing.
     case "$remote_name_" in
     HEAD)
 	note_= ;;
     refs/heads/*)
 	note_="$(expr "$remote_name_" : 'refs/heads/\(.*\)')"
 	note_="branch '$note_' of " ;;
     refs/tags/*)
 	note_="$(expr "$remote_name_" : 'refs/tags/\(.*\)')"
 	note_="tag '$note_' of " ;;
     refs/remotes/*)
 	note_="$(expr "$remote_name_" : 'refs/remotes/\(.*\)')"
 	note_="remote branch '$note_' of " ;;
     *)
 	note_="$remote_name of " ;;
     esac
     remote_1_=$(expr "z$remote_" : 'z\(.*\)\.git/*$') &&
 	remote_="$remote_1_"
     note_="$note_$remote_"

     # 2.6.11-tree tag would not be happy to be fed to resolve.
     if git-cat-file commit "$head_" >/dev/null 2>&1
     then
 	headc_=$(git-rev-parse --verify "$head_^0") || exit
 	echo "$headc_	$not_for_merge_	$note_" >>"$GIT_DIR/FETCH_HEAD"
     else
 	echo "$head_	not-for-merge	$note_" >>"$GIT_DIR/FETCH_HEAD"
     fi

     update_local_ref "$local_name_" "$head_" "$note_"
 }

 update_local_ref () {
     # If we are storing the head locally make sure that it is
     # a fast forward (aka "reverse push").

     label_=$(git-cat-file -t $2)
     newshort_=$(git-rev-parse --short $2)
     if test -z "$1" ; then
 	[ "$verbose" ] && echo >&2 "* fetched $3"
 	[ "$verbose" ] && echo >&2 "  $label_: $newshort_"
 	return 0
     fi
     oldshort_=$(git show-ref --hash --abbrev "$1" 2>/dev/null)

     case "$1" in
     refs/tags/*)
 	# Tags need not be pointing at commits so there
 	# is no way to guarantee "fast-forward" anyway.
 	if test -n "$oldshort_"
 	then
 		if now_=$(git show-ref --hash "$1") && test "$now_" = "$2"
 		then
 			[ "$verbose" ] && echo >&2 "* $1: same as $3"
 			[ "$verbose" ] && echo >&2 "  $label_: $newshort_" ||:
 		else
 			echo >&2 "* $1: updating with $3"
 			echo >&2 "  $label_: $newshort_"
 			git-update-ref -m "$GIT_REFLOG_ACTION: updating tag" "$1" "$2"
 		fi
 	else
 		echo >&2 "* $1: storing $3"
 		echo >&2 "  $label_: $newshort_"
 		git-update-ref -m "$GIT_REFLOG_ACTION: storing tag" "$1" "$2"
 	fi
 	;;

     refs/heads/* | refs/remotes/*)
 	# $1 is the ref being updated.
 	# $2 is the new value for the ref.
 	local=$(git-rev-parse --verify "$1^0" 2>/dev/null)
 	if test "$local"
 	then
 	    # Require fast-forward.
 	    mb=$(git-merge-base "$local" "$2") &&
 	    case "$2,$mb" in
 	    $local,*)
 	        if test -n "$verbose"
 		then
 			echo >&2 "* $1: same as $3"
 			echo >&2 "  $label_: $newshort_"
 		fi
 		;;
 	    *,$local)
 		echo >&2 "* $1: fast forward to $3"
 		echo >&2 "  old..new: $oldshort_..$newshort_"
 		git-update-ref -m "$GIT_REFLOG_ACTION: fast-forward" "$1" "$2" "$local"
 		;;
 	    *)
 		false
 		;;
 	    esac || {
 		case ",$force,$single_force," in
 		*,t,*)
 			echo >&2 "* $1: forcing update to non-fast forward $3"
 			echo >&2 "  old...new: $oldshort_...$newshort_"
 			git-update-ref -m "$GIT_REFLOG_ACTION: forced-update" "$1" "$2" "$local"
 			;;
 		*)
 			echo >&2 "* $1: not updating to non-fast forward $3"
 			echo >&2 "  old...new: $oldshort_...$newshort_"
 			exit 1
 			;;
 		esac
 	    }
 	else
 	    echo >&2 "* $1: storing $3"
 	    echo >&2 "  $label_: $newshort_"
 	    git-update-ref -m "$GIT_REFLOG_ACTION: storing head" "$1" "$2"
 	fi
 	;;
     esac
 }

 # updating the current HEAD with git-fetch in a bare
 # repository is always fine.
 if test -z "$update_head_ok" && test $(is_bare_repository) = false
 then
 	orig_head=$(git-rev-parse --verify HEAD 2>/dev/null)
 fi

 # If --tags (and later --heads or --all) is specified, then we are
 # not talking about defaults stored in Pull: line of remotes or
 # branches file, and just fetch those and refspecs explicitly given.
 # Otherwise we do what we always did.

 reflist=$(get_remote_refs_for_fetch "$@")
 if test "$tags"
 then
 	taglist=`IFS='	' &&
 		  echo "$ls_remote_result" |
 	          while read sha1 name
 		  do
 			case "$sha1" in
 			fail)
 				exit 1
 			esac
 			case "$name" in
 			*^*) continue ;;
 			refs/tags/*) ;;
 			*) continue ;;
 			esac
 		  	if git-check-ref-format "$name"
 			then
 			    echo ".${name}:${name}"
 			else
 			    echo >&2 "warning: tag ${name} ignored"
 			fi
 		  done` || exit
 	if test "$#" -gt 1
 	then
 		# remote URL plus explicit refspecs; we need to merge them.
 		reflist="$reflist$LF$taglist"
 	else
 		# No explicit refspecs; fetch tags only.
 		reflist=$taglist
 	fi
 fi

 fetch_main () {
   reflist="$1"
   refs=
   rref=

   for ref in $reflist
   do
       refs="$refs$LF$ref"

       # These are relative path from $GIT_DIR, typically starting at refs/
       # but may be HEAD
       if expr "z$ref" : 'z\.' >/dev/null
       then
 	  not_for_merge=t
 	  ref=$(expr "z$ref" : 'z\.\(.*\)')
       else
 	  not_for_merge=
       fi
       if expr "z$ref" : 'z+' >/dev/null
       then
 	  single_force=t
 	  ref=$(expr "z$ref" : 'z+\(.*\)')
       else
 	  single_force=
       fi
       remote_name=$(expr "z$ref" : 'z\([^:]*\):')
       local_name=$(expr "z$ref" : 'z[^:]*:\(.*\)')

       rref="$rref$LF$remote_name"

       # There are transports that can fetch only one head at a time...
       case "$remote" in
       http://* | https://* | ftp://*)
 	  test -n "$shallow_depth" &&
 		die "shallow clone with http not supported"
 	  proto=`expr "$remote" : '\([^:]*\):'`
 	  if [ -n "$GIT_SSL_NO_VERIFY" ]; then
 	      curl_extra_args="-k"
 	  fi
 	  if [ -n "$GIT_CURL_FTP_NO_EPSV" -o \
 		"`git-repo-config --bool http.noEPSV`" = true ]; then
 	      noepsv_opt="--disable-epsv"
 	  fi

 	  # Find $remote_name from ls-remote output.
 	  head=$(
 		IFS='	'
 		echo "$ls_remote_result" |
 		while read sha1 name
 		do
 			test "z$name" = "z$remote_name" || continue
 			echo "$sha1"
 			break
 		done
 	  )
 	  expr "z$head" : "z$_x40\$" >/dev/null ||
 		die "No such ref $remote_name at $remote"
 	  echo >&2 "Fetching $remote_name from $remote using $proto"
 	  git-http-fetch -v -a "$head" "$remote/" || exit
 	  ;;
       rsync://*)
 	  test -n "$shallow_depth" &&
 		die "shallow clone with rsync not supported"
 	  TMP_HEAD="$GIT_DIR/TMP_HEAD"
 	  rsync -L -q "$remote/$remote_name" "$TMP_HEAD" || exit 1
 	  head=$(git-rev-parse --verify TMP_HEAD)
 	  rm -f "$TMP_HEAD"
 	  test "$rsync_slurped_objects" || {
 	      rsync -av --ignore-existing --exclude info \
 		  "$remote/objects/" "$GIT_OBJECT_DIRECTORY/" || exit

 	      # Look at objects/info/alternates for rsync -- http will
 	      # support it natively and git native ones will do it on
 	      # the remote end.  Not having that file is not a crime.
 	      rsync -q "$remote/objects/info/alternates" \
 		  "$GIT_DIR/TMP_ALT" 2>/dev/null ||
 		  rm -f "$GIT_DIR/TMP_ALT"
 	      if test -f "$GIT_DIR/TMP_ALT"
 	      then
 		  resolve_alternates "$remote" <"$GIT_DIR/TMP_ALT" |
 		  while read alt
 		  do
 		      case "$alt" in 'bad alternate: '*) die "$alt";; esac
 		      echo >&2 "Getting alternate: $alt"
 		      rsync -av --ignore-existing --exclude info \
 		      "$alt" "$GIT_OBJECT_DIRECTORY/" || exit
 		  done
 		  rm -f "$GIT_DIR/TMP_ALT"
 	      fi
 	      rsync_slurped_objects=t
 	  }
 	  ;;
       *)
 	  # We will do git native transport with just one call later.
 	  continue ;;
       esac

       append_fetch_head "$head" "$remote" \
 	  "$remote_name" "$remote_nick" "$local_name" "$not_for_merge" || exit

   done

   case "$remote" in
   http://* | https://* | ftp://* | rsync://* )
       ;; # we are already done.
   *)
     ( : subshell because we muck with IFS
       IFS=" 	$LF"
       (
 	  git-fetch-pack --thin $exec $keep $shallow_depth "$remote" $rref ||
 	  echo failed "$remote"
       ) |
       (
 	trap '
 		if test -n "$keepfile" && test -f "$keepfile"
 		then
 			rm -f "$keepfile"
 		fi
 	' 0

         keepfile=
 	while read sha1 remote_name
 	do
 	  case "$sha1" in
 	  failed)
 		  echo >&2 "Fetch failure: $remote"
 		  exit 1 ;;
 	  # special line coming from index-pack with the pack name
 	  pack)
 		  continue ;;
 	  keep)
 		  keepfile="$GIT_OBJECT_DIRECTORY/pack/pack-$remote_name.keep"
 		  continue ;;
 	  esac
 	  found=
 	  single_force=
 	  for ref in $refs
 	  do
 	      case "$ref" in
 	      +$remote_name:*)
 		  single_force=t
 		  not_for_merge=
 		  found="$ref"
 		  break ;;
 	      .+$remote_name:*)
 		  single_force=t
 		  not_for_merge=t
 		  found="$ref"
 		  break ;;
 	      .$remote_name:*)
 		  not_for_merge=t
 		  found="$ref"
 		  break ;;
 	      $remote_name:*)
 		  not_for_merge=
 		  found="$ref"
 		  break ;;
 	      esac
 	  done
 	  local_name=$(expr "z$found" : 'z[^:]*:\(.*\)')
 	  append_fetch_head "$sha1" "$remote" \
 		  "$remote_name" "$remote_nick" "$local_name" \
 		  "$not_for_merge" || exit
         done
       )
     ) || exit ;;
   esac

 }

 fetch_main "$reflist" || exit

 # automated tag following
 case "$no_tags$tags" in
 '')
 	case "$reflist" in
 	*:refs/*)
 		# effective only when we are following remote branch
 		# using local tracking branch.
 		taglist=$(IFS='	' &&
 		echo "$ls_remote_result" |
 		git-show-ref --exclude-existing=refs/tags/ |
 		while read sha1 name
 		do
 			git-cat-file -t "$sha1" >/dev/null 2>&1 || continue
 			echo >&2 "Auto-following $name"
 			echo ".${name}:${name}"
 		done)
 	esac
 	case "$taglist" in
 	'') ;;
 	?*)
 		# do not deepen a shallow tree when following tags
 		shallow_depth=
 		fetch_main "$taglist" || exit ;;
 	esac
 esac

 # If the original head was empty (i.e. no "master" yet), or
 # if we were told not to worry, we do not have to check.
 case "$orig_head" in
 '')
 	;;
 ?*)
 	curr_head=$(git-rev-parse --verify HEAD 2>/dev/null)
 	if test "$curr_head" != "$orig_head"
 	then
 	    git-update-ref \
 			-m "$GIT_REFLOG_ACTION: Undoing incorrectly fetched HEAD." \
 			HEAD "$orig_head"
 		die "Cannot fetch into the current branch."
 	fi
 	;;
 esac
	#!/bin/sh
	#

	USAGE='<fetch-options> <repository> <refspec>...'
	SUBDIRECTORY_OK=Yes
	. git-sh-setup
	set_reflog_action "fetch $*"
	cd_to_toplevel ;# probably unnecessary...

	. git-parse-remote
	_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
	_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"

	LF='
	'
	IFS="$LF"

	no_tags=
	tags=
	append=
	force=
	verbose=
	update_head_ok=
	exec=
	upload_pack=
	keep=
	shallow_depth=
	while case "$#" in 0) break ;; esac
	do
	case "$1" in
	-a\|--a\|--ap\|--app\|--appe\|--appen\|--append)
	append=t
	;;
	--upl\|--uplo\|--uploa\|--upload\|--upload-\|--upload-p\|\
	--upload-pa\|--upload-pac\|--upload-pack)
	shift
	exec="--exec=$1"
	upload_pack="-u $1"
	;;
	-f\|--f\|--fo\|--for\|--forc\|--force)
	force=t
	;;
	-t\|--t\|--ta\|--tag\|--tags)
	tags=t
	;;
	-n\|--n\|--no\|--no-\|--no-t\|--no-ta\|--no-tag\|--no-tags)
	no_tags=t
	;;
	-u\|--u\|--up\|--upd\|--upda\|--updat\|--update\|--update-\|--update-h\|\
	--update-he\|--update-hea\|--update-head\|--update-head-\|\
	--update-head-o\|--update-head-ok)
	update_head_ok=t
	;;
	-v\|--verbose)
	verbose=Yes
	;;
	-k\|--k\|--ke\|--kee\|--keep)
	keep='-k -k'
	;;
	--depth=*)
	shallow_depth="--depth=`expr "z$1" : 'z-[^=]=\(.\)'`"
	;;
	--depth)
	shift
	shallow_depth="--depth=$1"
	;;
	-*)
	usage
	;;
	*)
	break
	;;
	esac
	shift
	done

	case "$#" in
	0)
	origin=$(get_default_remote)
	test -n "$(get_remote_url ${origin})" \|\|
	die "Where do you want to fetch from today?"
	set x $origin ; shift ;;
	esac

	remote_nick="$1"
	remote=$(get_remote_url "$@")
	refs=
	rref=
	rsync_slurped_objects=

	if test "" = "$append"
	then
	: >"$GIT_DIR/FETCH_HEAD"
	fi

	# Global that is reused later
	ls_remote_result=$(git ls-remote $upload_pack "$remote") \|\|
	die "Cannot get the repository state from $remote"

	append_fetch_head () {
	head_="$1"
	remote_="$2"
	remote_name_="$3"
	remote_nick_="$4"
	local_name_="$5"
	case "$6" in
	t) not_for_merge_='not-for-merge' ;;
	'') not_for_merge_= ;;
	esac

	# remote-nick is the URL given on the command line (or a shorthand)
	# remote-name is the $GIT_DIR relative refs/ path we computed
	# for this refspec.

	# the $note_ variable will be fed to git-fmt-merge-msg for further
	# processing.
	case "$remote_name_" in
	HEAD)
	note_= ;;
	refs/heads/*)
	note_="$(expr "$remote_name_" : 'refs/heads/\(.*\)')"
	note_="branch '$note_' of " ;;
	refs/tags/*)
	note_="$(expr "$remote_name_" : 'refs/tags/\(.*\)')"
	note_="tag '$note_' of " ;;
	refs/remotes/*)
	note_="$(expr "$remote_name_" : 'refs/remotes/\(.*\)')"
	note_="remote branch '$note_' of " ;;
	*)
	note_="$remote_name of " ;;
	esac
	remote_1_=$(expr "z$remote_" : 'z\(.\)\.git/$') &&
	remote_="$remote_1_"
	note_="$note_$remote_"

	# 2.6.11-tree tag would not be happy to be fed to resolve.
	if git-cat-file commit "$head_" >/dev/null 2>&1
	then
	headc_=$(git-rev-parse --verify "$head_^0") \|\| exit
	echo "$headc_ $not_for_merge_ $note_" >>"$GIT_DIR/FETCH_HEAD"
	else
	echo "$head_ not-for-merge $note_" >>"$GIT_DIR/FETCH_HEAD"
	fi

	update_local_ref "$local_name_" "$head_" "$note_"
	}

	update_local_ref () {
	# If we are storing the head locally make sure that it is
	# a fast forward (aka "reverse push").

	label_=$(git-cat-file -t $2)
	newshort_=$(git-rev-parse --short $2)
	if test -z "$1" ; then
	[ "$verbose" ] && echo >&2 "* fetched $3"
	[ "$verbose" ] && echo >&2 " $label_: $newshort_"
	return 0
	fi
	oldshort_=$(git show-ref --hash --abbrev "$1" 2>/dev/null)

	case "$1" in
	refs/tags/*)
	# Tags need not be pointing at commits so there
	# is no way to guarantee "fast-forward" anyway.
	if test -n "$oldshort_"
	then
	if now_=$(git show-ref --hash "$1") && test "$now_" = "$2"
	then
	[ "$verbose" ] && echo >&2 "* $1: same as $3"
	[ "$verbose" ] && echo >&2 " $label_: $newshort_" \|\|:
	else
	echo >&2 "* $1: updating with $3"
	echo >&2 " $label_: $newshort_"
	git-update-ref -m "$GIT_REFLOG_ACTION: updating tag" "$1" "$2"
	fi
	else
	echo >&2 "* $1: storing $3"
	echo >&2 " $label_: $newshort_"
	git-update-ref -m "$GIT_REFLOG_ACTION: storing tag" "$1" "$2"
	fi
	;;

	refs/heads/* \| refs/remotes/*)
	# $1 is the ref being updated.
	# $2 is the new value for the ref.
	local=$(git-rev-parse --verify "$1^0" 2>/dev/null)
	if test "$local"
	then
	# Require fast-forward.
	mb=$(git-merge-base "$local" "$2") &&
	case "$2,$mb" in
	$local,*)
	if test -n "$verbose"
	then
	echo >&2 "* $1: same as $3"
	echo >&2 " $label_: $newshort_"
	fi
	;;
	*,$local)
	echo >&2 "* $1: fast forward to $3"
	echo >&2 " old..new: $oldshort_..$newshort_"
	git-update-ref -m "$GIT_REFLOG_ACTION: fast-forward" "$1" "$2" "$local"
	;;
	*)
	false
	;;
	esac \|\| {
	case ",$force,$single_force," in
	,t,)
	echo >&2 "* $1: forcing update to non-fast forward $3"
	echo >&2 " old...new: $oldshort_...$newshort_"
	git-update-ref -m "$GIT_REFLOG_ACTION: forced-update" "$1" "$2" "$local"
	;;
	*)
	echo >&2 "* $1: not updating to non-fast forward $3"
	echo >&2 " old...new: $oldshort_...$newshort_"
	exit 1
	;;
	esac
	}
	else
	echo >&2 "* $1: storing $3"
	echo >&2 " $label_: $newshort_"
	git-update-ref -m "$GIT_REFLOG_ACTION: storing head" "$1" "$2"
	fi
	;;
	esac
	}

	# updating the current HEAD with git-fetch in a bare
	# repository is always fine.
	if test -z "$update_head_ok" && test $(is_bare_repository) = false
	then
	orig_head=$(git-rev-parse --verify HEAD 2>/dev/null)
	fi

	# If --tags (and later --heads or --all) is specified, then we are
	# not talking about defaults stored in Pull: line of remotes or
	# branches file, and just fetch those and refspecs explicitly given.
	# Otherwise we do what we always did.

	reflist=$(get_remote_refs_for_fetch "$@")
	if test "$tags"
	then
	taglist=`IFS=' ' &&
	echo "$ls_remote_result" \|
	while read sha1 name
	do
	case "$sha1" in
	fail)
	exit 1
	esac
	case "$name" in
	^) continue ;;
	refs/tags/*) ;;
	*) continue ;;
	esac
	if git-check-ref-format "$name"
	then
	echo ".${name}:${name}"
	else
	echo >&2 "warning: tag ${name} ignored"
	fi
	done` \|\| exit
	if test "$#" -gt 1
	then
	# remote URL plus explicit refspecs; we need to merge them.
	reflist="$reflist$LF$taglist"
	else
	# No explicit refspecs; fetch tags only.
	reflist=$taglist
	fi
	fi

	fetch_main () {
	reflist="$1"
	refs=
	rref=

	for ref in $reflist
	do
	refs="$refs$LF$ref"

	# These are relative path from $GIT_DIR, typically starting at refs/
	# but may be HEAD
	if expr "z$ref" : 'z\.' >/dev/null
	then
	not_for_merge=t
	ref=$(expr "z$ref" : 'z\.\(.*\)')
	else
	not_for_merge=
	fi
	if expr "z$ref" : 'z+' >/dev/null
	then
	single_force=t
	ref=$(expr "z$ref" : 'z+\(.*\)')
	else
	single_force=
	fi
	remote_name=$(expr "z$ref" : 'z\([^:]*\):')
	local_name=$(expr "z$ref" : 'z[^:]:\(.\)')

	rref="$rref$LF$remote_name"

	# There are transports that can fetch only one head at a time...
	case "$remote" in
	http://* \| https://* \| ftp://*)
	test -n "$shallow_depth" &&
	die "shallow clone with http not supported"
	proto=`expr "$remote" : '\([^:]*\):'`
	if [ -n "$GIT_SSL_NO_VERIFY" ]; then
	curl_extra_args="-k"
	fi
	if [ -n "$GIT_CURL_FTP_NO_EPSV" -o \
	"`git-repo-config --bool http.noEPSV`" = true ]; then
	noepsv_opt="--disable-epsv"
	fi

	# Find $remote_name from ls-remote output.
	head=$(
	IFS=' '
	echo "$ls_remote_result" \|
	while read sha1 name
	do
	test "z$name" = "z$remote_name" \|\| continue
	echo "$sha1"
	break
	done
	)
	expr "z$head" : "z$_x40\$" >/dev/null \|\|
	die "No such ref $remote_name at $remote"
	echo >&2 "Fetching $remote_name from $remote using $proto"
	git-http-fetch -v -a "$head" "$remote/" \|\| exit
	;;
	rsync://*)
	test -n "$shallow_depth" &&
	die "shallow clone with rsync not supported"
	TMP_HEAD="$GIT_DIR/TMP_HEAD"
	rsync -L -q "$remote/$remote_name" "$TMP_HEAD" \|\| exit 1
	head=$(git-rev-parse --verify TMP_HEAD)
	rm -f "$TMP_HEAD"
	test "$rsync_slurped_objects" \|\| {
	rsync -av --ignore-existing --exclude info \
	"$remote/objects/" "$GIT_OBJECT_DIRECTORY/" \|\| exit

	# Look at objects/info/alternates for rsync -- http will
	# support it natively and git native ones will do it on
	# the remote end. Not having that file is not a crime.
	rsync -q "$remote/objects/info/alternates" \
	"$GIT_DIR/TMP_ALT" 2>/dev/null \|\|
	rm -f "$GIT_DIR/TMP_ALT"
	if test -f "$GIT_DIR/TMP_ALT"
	then
	resolve_alternates "$remote" <"$GIT_DIR/TMP_ALT" \|
	while read alt
	do
	case "$alt" in 'bad alternate: '*) die "$alt";; esac
	echo >&2 "Getting alternate: $alt"
	rsync -av --ignore-existing --exclude info \
	"$alt" "$GIT_OBJECT_DIRECTORY/" \|\| exit
	done
	rm -f "$GIT_DIR/TMP_ALT"
	fi
	rsync_slurped_objects=t
	}
	;;
	*)
	# We will do git native transport with just one call later.
	continue ;;
	esac

	append_fetch_head "$head" "$remote" \
	"$remote_name" "$remote_nick" "$local_name" "$not_for_merge" \|\| exit

	done

	case "$remote" in
	http://* \| https://* \| ftp://* \| rsync://* )
	;; # we are already done.
	*)
	( : subshell because we muck with IFS
	IFS=" $LF"
	(
	git-fetch-pack --thin $exec $keep $shallow_depth "$remote" $rref \|\|
	echo failed "$remote"
	) \|
	(
	trap '
	if test -n "$keepfile" && test -f "$keepfile"
	then
	rm -f "$keepfile"
	fi
	' 0

	keepfile=
	while read sha1 remote_name
	do
	case "$sha1" in
	failed)
	echo >&2 "Fetch failure: $remote"
	exit 1 ;;
	# special line coming from index-pack with the pack name
	pack)
	continue ;;
	keep)
	keepfile="$GIT_OBJECT_DIRECTORY/pack/pack-$remote_name.keep"
	continue ;;
	esac
	found=
	single_force=
	for ref in $refs
	do
	case "$ref" in
	+$remote_name:*)
	single_force=t
	not_for_merge=
	found="$ref"
	break ;;
	.+$remote_name:*)
	single_force=t
	not_for_merge=t
	found="$ref"
	break ;;
	.$remote_name:*)
	not_for_merge=t
	found="$ref"
	break ;;
	$remote_name:*)
	not_for_merge=
	found="$ref"
	break ;;
	esac
	done
	local_name=$(expr "z$found" : 'z[^:]:\(.\)')
	append_fetch_head "$sha1" "$remote" \
	"$remote_name" "$remote_nick" "$local_name" \
	"$not_for_merge" \|\| exit
	done
	)
	) \|\| exit ;;
	esac

	}

	fetch_main "$reflist" \|\| exit

	# automated tag following
	case "$no_tags$tags" in
	'')
	case "$reflist" in
	:refs/)
	# effective only when we are following remote branch
	# using local tracking branch.
	taglist=$(IFS=' ' &&
	echo "$ls_remote_result" \|
	git-show-ref --exclude-existing=refs/tags/ \|
	while read sha1 name
	do
	git-cat-file -t "$sha1" >/dev/null 2>&1 \|\| continue
	echo >&2 "Auto-following $name"
	echo ".${name}:${name}"
	done)
	esac
	case "$taglist" in
	'') ;;
	?*)
	# do not deepen a shallow tree when following tags
	shallow_depth=
	fetch_main "$taglist" \|\| exit ;;
	esac
	esac

	# If the original head was empty (i.e. no "master" yet), or
	# if we were told not to worry, we do not have to check.
	case "$orig_head" in
	'')
	;;
	?*)
	curr_head=$(git-rev-parse --verify HEAD 2>/dev/null)
	if test "$curr_head" != "$orig_head"
	then
	git-update-ref \
	-m "$GIT_REFLOG_ACTION: Undoing incorrectly fetched HEAD." \
	HEAD "$orig_head"
	die "Cannot fetch into the current branch."
	fi
	;;
	esac