libmakepkg: add routine for linting $SOURCE_DATE_EPOCH

This can only ever be an int, and the specification states that a
malformed timestamp should be considered a fatal error.

https://reproducible-builds.org/specs/source-date-epoch/

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

2 files changed, 38 insertions, 0 deletions

diff --git a/scripts/libmakepkg/lint_config/meson.build b/scripts/libmakepkg/lint_config/meson.build
index 884d63d7..144705f9 100644
--- a/scripts/libmakepkg/lint_config/meson.build
+++ b/scripts/libmakepkg/lint_config/meson.build
@@ -2,6 +2,7 @@ libmakepkg_module = 'lint_config'
 
 sources = [
   'paths.sh.in',
+  'source_date_epoch.sh.in',
   'variable.sh.in',
 ]
 
diff --git a/scripts/libmakepkg/lint_config/source_date_epoch.sh.in b/scripts/libmakepkg/lint_config/source_date_epoch.sh.in
new file mode 100755
index 00000000..38fbfd77
--- /dev/null
+++ b/scripts/libmakepkg/lint_config/source_date_epoch.sh.in
@@ -0,0 +1,37 @@
+#!/bin/bash
+#
+#   source_date_epoch.sh - Check that reproducible builds timestamp is valid
+#
+#   Copyright (c) 2018 Pacman Development Team <pacman-dev@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 $LIBMAKEPKG_LINT_CONFIG_SOURCE_DATE_EPOCH_SH ]] && return
+LIBMAKEPKG_LINT_CONFIG_SOURCE_DATE_EPOCH_SH=1
+
+LIBRARY=${LIBRARY:-'@libmakepkgdir@'}
+
+source "$LIBRARY/util/message.sh"
+
+lint_config_functions+=('lint_source_date_epoch')
+
+
+lint_source_date_epoch() {
+	if [[ $SOURCE_DATE_EPOCH = *[^[:digit:]]* ]]; then
+		error "$(gettext "%s contains invalid characters: %s")" \
+			"\$SOURCE_DATE_EPOCH" "${SOURCE_DATE_EPOCH//[[:digit:]]}"
+		return 1
+	fi
+}