Merge commit 'b19a54d2f9d8a3e83366c638aace4cf3b5daa96e' as 'build/dobuild'

build/dobuild/bin/get_source_date_epoch

@@ -0,0 +1,40 @@
+#!/bin/sh
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+#
+# This file is part of dobuild.
+# Copyright (c) 2019 Contributors as noted in the AUTHORS file.
+#
+# SPDX-License-Identifier: MPL-2.0
+
+exec 0<&-
+
+set -e
+
+export LANG=C
+export LC_ALL=C
+
+TOPDIR="$1"
+
+[ -z "$TOPDIR" ] || cd "$TOPDIR"
+
+try_git() {
+  [ -d .git ] || return 1
+  git show -s --format=format:%ct HEAD
+}
+
+try_svn() {
+  [ -d .svn ] || return 1
+  LAST_CHANGED_DATE="$(svn info | sed -n -e 's/^Last Changed Date: //p')"
+  [ -n "$LAST_CHANGED_DATE" ] || return 2
+  SOURCE_DATE_EPOCH="$(date -d "$LAST_CHANGED_DATE" +%s)"
+}
+
+try_mtime() {
+  stat -c '%Y' "$PWD"
+}
+
+SOURCE_DATE_EPOCH="$(try_git || try_svn || try_mtime)"
+echo "$SOURCE_DATE_EPOCH"