From 4f7a53dd36315e5f280d4553dc58bc3226e6ccc2 Mon Sep 17 00:00:00 2001
From: Kornilios Kourtis <kornilios@isovalent.com>
Date: Tue, 18 Feb 2025 15:14:19 +0100
Subject: [PATCH] api/Makefile: make it work for worktrees

Signed-off-by: Kornilios Kourtis <kornilios@isovalent.com>
---
 api/Makefile                       |  4 +--
 contrib/scripts/repo-docker-run.sh | 54 ++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+), 2 deletions(-)
 create mode 100755 contrib/scripts/repo-docker-run.sh

diff --git a/api/Makefile b/api/Makefile
index e8ec8c6f43d..9b862f6b582 100644
--- a/api/Makefile
+++ b/api/Makefile
@@ -30,7 +30,7 @@ __check-breaking_local:
 
 .PHONY: proto lint format check-breaking
 all proto lint format check-breaking:
-	$(CONTAINER_ENGINE) container run --rm \
+	../contrib/scripts/repo-docker-run.sh --rm \
 		--volume $(CURDIR)/..:/src \
 		--workdir /src/api \
 		--user "$(shell id -u):$(shell id -g)" \
@@ -39,7 +39,7 @@ all proto lint format check-breaking:
 
 .PHONY: debug
 debug:
-	@echo $(CONTAINER_ENGINE) container run --rm \
+	@echo ../contrib/scripts/repo-docker-run.sh --rm \
 		--volume $(CURDIR)/..:/src \
 		--workdir /src/api \
 		--user "$(shell id -u):$(shell id -g)" \
diff --git a/contrib/scripts/repo-docker-run.sh b/contrib/scripts/repo-docker-run.sh
new file mode 100755
index 00000000000..c9d78ce2ab4
--- /dev/null
+++ b/contrib/scripts/repo-docker-run.sh
@@ -0,0 +1,54 @@
+#!/usr/bin/env bash
+#
+# Running things that use the git command in a container might result in issues when using bare git
+# directories, worktrees, or repositories cloned with --shared. This script aims to address that.
+#
+# See: https://github.com/buildroot/buildroot/blob/master/utils/docker-run
+
+
+DIR=$(dirname "${0}")
+MAIN_DIR=$(readlink -f "${DIR}/..")
+if [ -L "${MAIN_DIR}/.git/config" ]; then
+    # Support git-new-workdir
+    GIT_DIR="$(dirname "$(realpath "${MAIN_DIR}/.git/config")")"
+else
+    # Support git-worktree
+    GIT_DIR="$(cd "${MAIN_DIR}" && git rev-parse --no-flags --git-common-dir)"
+fi
+
+declare -a mountpoints=(
+    "${MAIN_DIR}"
+)
+
+# Empty GIT_DIR means that we are not in a workdir, *and* git is too old
+# to know about worktrees, so we're not in a worktree either. So it means
+# we're in the main git working copy, and thus we don't need to mount the
+# .git directory.
+if [ "${GIT_DIR}" ]; then
+    # GIT_DIR in the main working copy (when git supports worktrees) will
+    # be just '.git', but 'docker run' needs an absolute path. If it is
+    # not absolute, GIT_DIR is relative to MAIN_DIR. If it's an absolute
+    # path already (in a wordir), then that's a noop.
+    GIT_DIR="$(cd "${MAIN_DIR}"; readlink -e "${GIT_DIR}")"
+    mountpoints+=( "${GIT_DIR}" )
+
+    # 'repo' stores .git/objects separately.
+    if [ -L "${GIT_DIR}/objects" ]; then
+        # GITDIR is already an absolute path, but for symetry
+        # with the above, keep the same cd+readlink construct.
+        OBJECTS_DIR="$(cd "${MAIN_DIR}"; readlink -e "${GIT_DIR}/objects")"
+        mountpoints+=( "${OBJECTS_DIR}" )
+    fi
+fi
+
+declare -a docker_opts=(
+    --rm
+    --user "$(id -u):$(id -g)"
+)
+
+# shellcheck disable=SC2013 # can't use while-read because of the assignment
+for dir in $(printf '%s\n' "${mountpoints[@]}" |LC_ALL=C sort -u); do
+    docker_opts+=( --mount "type=bind,src=${dir},dst=${dir}" )
+done
+
+docker run "${docker_opts[@]}" "${@}"