1 files changed, 73 insertions, 0 deletions
diff --git a/bin/buildrc b/bin/buildrc
new file mode 100644
index 0000000..237f0b2
--- /dev/null
+++ b/bin/buildrc
@@ -0,0 +1,73 @@
+#!/bin/bash
+
+_exec_locked() {
+	local tmp_dir="/var/tmp"
+	local lvm_snapshot_lock_file="/.entropy_locks/vg_chroots-lv_chroots-snapshot.lock"
+	local snapshot_lock_file="${tmp_dir}/.emerge.snapshot.lock"
+	local matter_lock_file="${tmp_dir}/.matter_resource.lock"
+
+	if [ ! -d "${tmp_dir}" ]; then
+		echo "${tmp_dir} is missing, creating it..." >&2
+		mkdir -p "${tmp_dir}"
+	fi
+
+	flock -x -n "${matter_lock_file}" true
+	rc=${?}
+	if [ "${rc}" != "0" ]; then
+		echo >&2
+		echo "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" >&2
+		echo "Matter or the Backup Script is running on this chroot" >&2
+		echo "Please be patient, it will eventually terminate..." >&2
+		echo "Snapshot lock file = ${snapshot_lock_file}" >&2
+		echo "Matter lock file = ${matter_lock_file}" >&2
+		echo >&2
+		echo "This ${1} instance will terminate NOW" >&2
+		echo "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" >&2
+		echo >&2
+		return 1
+	else
+		# acquire snapshot read lock in non-blocking, shared mode
+		(
+			flock -s -n 9 || {
+				echo "Hello there," >&2;
+				echo "a chroot snapshot is in progress..." >&2;
+				echo "Try again later." >&2;
+				exit 1;
+			}
+
+			flock -s --timeout=120 10
+			if [ "${?}" != "0" ]; then
+				echo >&2
+				echo "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" >&2
+				echo "The LVM lock of the Backup Script is being held for 2 minutes" >&2
+				echo "This should not happen. Please contact stefan.cristian@rogentos.ro and" >&2
+				echo "stop any activity NOW. However, if you're in an emergency" >&2
+				echo "Just rm ${lvm_snapshot_lock_file} and continue." >&2
+				echo "Please note that this will cause inconsistent backups." >&2
+				echo >&2
+				echo "This instance will terminate NOW" >&2
+				echo "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" >&2
+				echo >&2
+				exit 1
+			fi
+
+			"${@}"
+			exit ${?}
+
+		) 9> "${snapshot_lock_file}" 10>"${lvm_snapshot_lock_file}"
+		return ${?}
+	fi
+}
+
+emerge() {
+	_exec_locked "/usr/bin/emerge" --quiet-build=y --oneshot "${@}"
+	return ${?}
+}
+
+eit() {
+	_exec_locked "/usr/bin/eit" "${@}"
+	return ${?}
+}
+
+# Alias configuration
+alias cosmos=/particles/cosmos/cosmos