File reproducible.patch of Package plowshare

From db87b3d2bef6b2f3d52e50fa80eabee53eefab75 Mon Sep 17 00:00:00 2001
From: Matthieu Crapet <mcrapet@gmail.com>
Date: Sun, 13 Aug 2017 10:02:13 +0200
Subject: [PATCH] scripts/version: support SOURCE_DATE_EPOCH environment
 variable

Make builds reproductible.
See https://reproducible-builds.org/specs/source-date-epoch/ for more information.
Credits go to Bernhard M. Wiedemann (PR#98).
---
 scripts/version | 28 ++++++++++++++++++++++++----
 1 file changed, 24 insertions(+), 4 deletions(-)

diff --git a/scripts/version b/scripts/version
index ea77887b..4080f9e9 100755
--- a/scripts/version
+++ b/scripts/version
@@ -1,5 +1,9 @@
 #!/bin/sh -e
 #
+# Checked environment variables:
+# - PLOWSHARE_FORCE_VERSION
+# - SOURCE_DATE_EPOCH (see reproducible-builds.org)
+#
 # Note:
 # Choose "git describe" revision syntax: v1.0.1-17-g390e0fa
 # over usual (distro) one: 1.0.1~git20140411-390e0fa
@@ -8,17 +12,33 @@ if [ $# -ne 0 ]; then
   echo 'warning: this script does not take any argument.' >&2
 fi
 
+datefmt='%Y-%m-%d'
+if [ -n "$SOURCE_DATE_EPOCH" ]; then
+  if date --version 2>/dev/null | head -n1 | grep -q GNU; then
+    date=$(date -u -d "@$SOURCE_DATE_EPOCH" +$datefmt)
+  else
+    date=$(date -u -r "$SOURCE_DATE_EPOCH" +$datefmt)
+  fi
+else
+  date=$(date -u +$datefmt)
+fi
+
 # Check environment variable PLOWSHARE_FORCE_VERSION
 # For example: "1.0.1"
 if [ -n "$PLOWSHARE_FORCE_VERSION" ]; then
-  date=$(date +'%Y-%m-%d')
   echo "v${PLOWSHARE_FORCE_VERSION#v} ($date)"
 elif git rev-parse --is-inside-work-tree 1>/dev/null 2>&1; then
   rev=$(git describe --always --tags)
   date=$(git log "$rev" -n1 --pretty=%ci | cut -d' ' -f1)
   echo "$rev ($date)"
 else
-  echo 'warning: unable to detect plowshare version.' >&2
-  date=$(date +'%Y-%m-%d')
-  echo "UNKNOWN ($date)"
+  # Check directory name. For example: plowshare-2.1.7
+  dir=$(basename "$PWD")
+  v=${dir##*-}
+  if echo $v | grep -q '[2-9]\(\.[0-9]\)\{2\}'; then
+    echo "v$v ($date)"
+  else
+    echo 'warning: unable to detect plowshare version.' >&2
+    echo "UNKNOWN ($date)"
+  fi
 fi