archive-source: also create a stash for submodules

"git archive" fails when a submodule has a modification, because "git
stash create" doesn't handle submodules. Let's teach our
archive-source.sh to handle modifications in submodules the same way
as qemu tree, by creating a stash.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190708200250.12017-1-marcandre.lureau@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

scripts/archive-source.sh

@@ -39,14 +39,16 @@ function cleanup() {
 }
 trap "cleanup" 0 1 2 3 15
 
-if git diff-index --quiet HEAD -- &>/dev/null
-then
-    HEAD=HEAD
-else
-    HEAD=$(git stash create)
-fi
+function tree_ish() {
+    local retval='HEAD'
+    if ! git diff-index --quiet --ignore-submodules=all HEAD -- &>/dev/null
+    then
+        retval=$(git stash create)
+    fi
+    echo "$retval"
+}
 
-git archive --format tar $HEAD > "$tar_file"
+git archive --format tar "$(tree_ish)" > "$tar_file"
 test $? -ne 0 && error "failed to archive qemu"
 for sm in $submodules; do
     status="$(git submodule status "$sm")"
@@ -62,7 +64,7 @@ for sm in $submodules; do
             echo "WARNING: submodule $sm is out of sync"
             ;;
     esac
-    (cd $sm; git archive --format tar --prefix "$sm/" $smhash) > "$sub_file"
+    (cd $sm; git archive --format tar --prefix "$sm/" $(tree_ish)) > "$sub_file"
     test $? -ne 0 && error "failed to archive submodule $sm ($smhash)"
     tar --concatenate --file "$tar_file" "$sub_file"
     test $? -ne 0 && error "failed append submodule $sm to $tar_file"