From b99dc98780c97a005fe0143a46562d838b55bb84 Mon Sep 17 00:00:00 2001
From: Luca Boccassi <bluca@debian.org>
Date: Thu, 6 Jun 2024 00:14:37 +0100
Subject: [PATCH] mkosi: do a sparse checkout of debian/ubuntu packaging repo

The repository on Salsa includes the full upstream sources, which means
they are duplicated, taking extra space and showing duplicated grep results.
But we only need the debian/ subfolder, so do a sparse clone and checkout.
---
 .../mkosi.conf.d/10-debian-ubuntu/mkosi.conf      |  1 +
 mkosi.images/system/mkosi.sync                    | 15 ++++++++++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/mkosi.images/system/mkosi.conf.d/10-debian-ubuntu/mkosi.conf b/mkosi.images/system/mkosi.conf.d/10-debian-ubuntu/mkosi.conf
index abb55884ee5..964ade73254 100644
--- a/mkosi.images/system/mkosi.conf.d/10-debian-ubuntu/mkosi.conf
+++ b/mkosi.images/system/mkosi.conf.d/10-debian-ubuntu/mkosi.conf
@@ -7,6 +7,7 @@ Distribution=|ubuntu
 [Content]
 Environment=
         GIT_URL=https://salsa.debian.org/systemd-team/systemd.git
+        GIT_SUBDIR=debian
         GIT_BRANCH=debian/master
         GIT_COMMIT=5b9607385d49c09440e6e3b35c03ceec73162aec
 
diff --git a/mkosi.images/system/mkosi.sync b/mkosi.images/system/mkosi.sync
index 6856af7c6b0..d21ecd19808 100755
--- a/mkosi.images/system/mkosi.sync
+++ b/mkosi.images/system/mkosi.sync
@@ -13,8 +13,21 @@ if [[ -d "$PKG_SUBDIR/.git" ]] && [[ "$(git -C "$PKG_SUBDIR" rev-parse HEAD)" ==
     exit 0
 fi
 
+# The repository on Salsa has the full upstream sources, so it's a waste of space to
+# redownload and duplicate everything, so do a sparse checkout as we only need the
+# packaging directory anyway
+if [[ -n "${GIT_SUBDIR:-}" ]]; then
+    sparse=(--no-checkout --filter=tree:0)
+else
+    sparse=()
+fi
+
 if [[ ! -e "$PKG_SUBDIR" ]] || [[ -z "$(ls --almost-all "$PKG_SUBDIR")" ]]; then
-    git clone "$GIT_URL" --branch "$GIT_BRANCH" "$PKG_SUBDIR"
+    git clone "$GIT_URL" --branch "$GIT_BRANCH" "${sparse[@]}" "$PKG_SUBDIR"
+    if [[ -n "${GIT_SUBDIR:-}" ]]; then
+        # --no-cone is needed to check out only one top-level directory
+        git -C "$PKG_SUBDIR" sparse-checkout set --no-cone "${GIT_SUBDIR:-}"
+    fi
 else
     git -C "$PKG_SUBDIR" remote set-url origin "$GIT_URL"
     git -C "$PKG_SUBDIR" fetch origin "$GIT_BRANCH"
-- 
2.47.3