makepkg: move SOURCE_DATE_EPOCH handling to libmakepkg

Signed-off-by: Allan McRae <allan@archlinux.org>

scripts/libmakepkg/reproducible/meson.build

@@ -2,6 +2,7 @@ libmakepkg_module = 'reproducible'
 
 sources = [
   'python.sh.in',
+  'source_date_epoch.sh.in',
 ]
 
 foreach src : sources

scripts/libmakepkg/reproducible/source_date_epoch.sh.in

@@ -0,0 +1,33 @@
+#!/bin/bash
+#
+#   source_date_epoch.sh - handle SOURCE_DATE_EPOCH variable for reproducibility
+#
+#   Copyright (c) 2017-2024 Pacman Development Team <pacman-dev@lists.archlinux.org>
+#
+#   This program is free software; you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation; either version 2 of the License, or
+#   (at your option) any later version.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+[[ -n "$LIBMAKEPKG_REPRODUCIBLE_SOURCE_DATE_EPOCH_SH" ]] && return
+LIBMAKEPKG_REPRODUCIBLE_SOURCE_DATE_EPOCH_SH=1
+
+
+MAKEPKG_LIBRARY=${MAKEPKG_LIBRARY:-'@libmakepkgdir@'}
+
+
+if [[ -n $SOURCE_DATE_EPOCH ]]; then
+	REPRODUCIBLE=1
+else
+	SOURCE_DATE_EPOCH=$(date +%s)
+fi
+export SOURCE_DATE_EPOCH

scripts/makepkg.sh.in

@@ -80,13 +80,6 @@ SPLITPKG=0
 SOURCEONLY=0
 VERIFYSOURCE=0
 
-if [[ -n $SOURCE_DATE_EPOCH ]]; then
-	REPRODUCIBLE=1
-else
-	SOURCE_DATE_EPOCH=$(date +%s)
-fi
-export SOURCE_DATE_EPOCH
-
 MAKEPKG_LINT_PKGBUILD=${MAKEPKG_LINT_PKGBUILD:-1}
 
 PACMAN_OPTS=()