submodule.c: fetch in submodules git directory instead of in worktree

diff --git a/git-submodule.sh b/git-submodule.sh
index 1b568e29b9a09af9fdecf19ddb75ffd2bdc6e094..5e608f8bad305fea40e9063b854bf1be24ebd448 100755 (executable)
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -72,7 +72,7 @@ get_submodule_config () {
        value=$(git config submodule."$name"."$option")
        if test -z "$value"
        then
-               value=$(git config -f .gitmodules submodule."$name"."$option")
+               value=$(git submodule--helper config submodule."$name"."$option")
        fi
        printf '%s' "${value:-$default}"
 }
@@ -82,6 +82,11 @@ isnumber()
        n=$(($1 + 0)) 2>/dev/null && test "$n" = "$1"
 }
 
+# Given a full hex object ID, is this the zero OID?
+is_zero_oid () {
+       echo "$1" | sane_egrep '^0+$' >/dev/null 2>&1
+}
+
 # Sanitize the local git environment for use within a submodule. We
 # can't simply use clear_local_git_env since we want to preserve some
 # of the settings from GIT_CONFIG_PARAMETERS.
@@ -159,6 +164,11 @@ cmd_add()
                shift
        done
 
+       if ! git submodule--helper config --check-writeable >/dev/null 2>&1
+       then
+                die "$(eval_gettext "please make sure that the .gitmodules file is in the working tree")"
+       fi
+
        if test -n "$reference_path"
        then
                is_absolute_path "$reference_path" ||
@@ -283,11 +293,11 @@ or you are unsure what this means choose another name with the '--name' option."
        git add --no-warn-embedded-repo $force "$sm_path" ||
        die "$(eval_gettext "Failed to add submodule '\$sm_path'")"
 
-       git config -f .gitmodules submodule."$sm_name".path "$sm_path" &&
-       git config -f .gitmodules submodule."$sm_name".url "$repo" &&
+       git submodule--helper config submodule."$sm_name".path "$sm_path" &&
+       git submodule--helper config submodule."$sm_name".url "$repo" &&
        if test -n "$branch"
        then
-               git config -f .gitmodules submodule."$sm_name".branch "$branch"
+               git submodule--helper config submodule."$sm_name".branch "$branch"
        fi &&
        git add --force .gitmodules ||
        die "$(eval_gettext "Failed to register submodule '\$sm_path'")"
@@ -780,7 +790,7 @@ cmd_summary() {
        while read -r mod_src mod_dst sha1_src sha1_dst status name
        do
                if test -z "$cached" &&
-                       test $sha1_dst = 0000000000000000000000000000000000000000
+                       is_zero_oid $sha1_dst
                then
                        case "$mod_dst" in
                        160000)