submodule: move core cmd_update() logic to C

This patch completes the conversion past the flag parsing of
`submodule update` by introducing a helper subcommand called
`submodule--helper update`. The behaviour of `submodule update` should
remain the same after this patch.

Prior to this patch, `submodule update` was implemented by piping the
output of `update-clone` (which clones all missing submodules, then
prints relevant information for all submodules) into
`run-update-procedure` (which reads the information and updates the
submodule tree).

With `submodule--helper update`, we iterate over the submodules and
update the submodule tree in the same process. This reuses most of
existing code structure, except that `update_submodule()` now updates
the submodule tree (instead of printing submodule information to be
consumed by another process).

Recursing on a submodule is done by calling a subprocess that launches
`submodule--helper update`, with a modified `--recursive-prefix` and
`--prefix` parameter.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Shourya Shukla <periperidip@gmail.com>
Signed-off-by: Atharva Raykar <raykar.ath@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 7 insertions, 97 deletions

diff --git a/git-submodule.sh b/git-submodule.sh
index b63a2aefa7..fd0b4a2c94 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -51,14 +51,6 @@ jobs=
 recommend_shallow=
 filter=
 
-die_if_unmatched ()
-{
-	if test "$1" = "#unmatched"
-	then
-		exit ${2:-1}
-	fi
-}
-
 isnumber()
 {
 	n=$(($1 + 0)) 2>/dev/null && test "$n" = "$1"
@@ -356,11 +348,14 @@ cmd_update()
 		shift
 	done
 
-	{
-	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper update-clone \
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper update \
 		${GIT_QUIET:+--quiet} \
+		${force:+--force} \
 		${progress:+"--progress"} \
+		${remote:+--remote} \
+		${recursive:+--recursive} \
 		${init:+--init} \
+		${nofetch:+--no-fetch} \
 		${wt_prefix:+--prefix "$wt_prefix"} \
 		${prefix:+--recursive-prefix "$prefix"} \
 		${update:+--update "$update"} \
@@ -368,98 +363,13 @@ cmd_update()
 		${dissociate:+"--dissociate"} \
 		${depth:+"$depth"} \
 		${require_init:+--require-init} \
+		${dissociate:+"--dissociate"} \
 		$single_branch \
 		$recommend_shallow \
 		$jobs \
 		$filter \
 		-- \
-		"$@" || echo "#unmatched" $?
-	} | {
-	err=
-	while read -r quickabort sha1 just_cloned sm_path
-	do
-		die_if_unmatched "$quickabort" "$sha1"
-
-		displaypath=$(git submodule--helper relative-path "$prefix$sm_path" "$wt_prefix")
-
-		if test $just_cloned -eq 0
-		then
-			just_cloned=
-		fi
-
-		out=$(git submodule--helper run-update-procedure \
-			  ${wt_prefix:+--prefix "$wt_prefix"} \
-			  ${GIT_QUIET:+--quiet} \
-			  ${force:+--force} \
-			  ${just_cloned:+--just-cloned} \
-			  ${nofetch:+--no-fetch} \
-			  ${depth:+"$depth"} \
-			  ${update:+--update "$update"} \
-			  ${prefix:+--recursive-prefix "$prefix"} \
-			  ${sha1:+--oid "$sha1"} \
-			  ${remote:+--remote} \
-			  "--" \
-			  "$sm_path")
-
-		# exit codes for run-update-procedure:
-		# 0: update was successful, say command output
-		# 1: update procedure failed, but should not die
-		# 128: subcommand died during execution
-		# 3: no update procedure was run
-		res="$?"
-		case $res in
-		0)
-			say "$out"
-			;;
-		1)
-			err="${err};$out"
-			continue
-			;;
-		128)
-			printf >&2 "$out"
-			exit $res
-			;;
-		esac
-
-		if test -n "$recursive"
-		then
-			(
-				prefix=$(git submodule--helper relative-path "$prefix$sm_path/" "$wt_prefix")
-				wt_prefix=
-				sanitize_submodule_env
-				cd "$sm_path" &&
-				eval cmd_update
-			)
-			res=$?
-			if test $res -gt 0
-			then
-				die_msg="fatal: $(eval_gettext "Failed to recurse into submodule path '\$displaypath'")"
-				if test $res -ne 2
-				then
-					err="${err};$die_msg"
-					continue
-				else
-					die_with_status $res "$die_msg"
-				fi
-			fi
-		fi
-	done
-
-	if test -n "$err"
-	then
-		OIFS=$IFS
-		IFS=';'
-		for e in $err
-		do
-			if test -n "$e"
-			then
-				echo >&2 "$e"
-			fi
-		done
-		IFS=$OIFS
-		exit 1
-	fi
-	}
+		"$@"
 }
 
 #