Bug#914252: gnuradio: please make the output of grcc reproducible

[Chris Lamb]

Source: gnuradio
Version: 3.7.13.4-2
Severity: wishlist
Tags: patch
User: reproducible-builds at lists.alioth.debian.org
Usertags: timestamps toolchain
X-Debbugs-Cc: reproducible-bugs at lists.alioth.debian.org

Hi,

Whilst working on the Reproducible Builds effort [0], we noticed
that gnuradio generates output that is not reproducible, affecting
other packages.

.grc files are compiled by the grcc utility which adds a Generated
timestamp header. For example:

│ │ │ ├── ./usr/bin/grgsm_livemon_headless
│ │ │ │ @@ -1,15 +1,15 @@
│ │ │ │  #! /usr/bin/python2
│ │ │ │  # -*- coding: utf-8 -*-
│ │ │ │  ##################################################
│ │ │ │  # GNU Radio Python Flow Graph
│ │ │ │  # Title: Gr-gsm Livemon
│ │ │ │  # Author: Piotr Krysik
│ │ │ │  # Description: Interactive monitor of a single C0 channel with analysis performed by Wireshark (command to run wireshark: sudo wireshark -k -f udp -Y gsmtap -i lo)
│ │ │ │ -# Generated: Sat Dec 21 20:48:21 2019
│ │ │ │ +# Generated: Mon Nov 19 16:56:32 2018
│ │ │ │  ##################################################

Patch attached.

  [0] https://reproducible-builds.org/


Regards,

-- 
      ,''`.
     : :'  :     Chris Lamb
     `. `'`      lamby at debian.org / chris-lamb.co.uk
       `-
-------------- next part --------------
diff --git a/grc/core/generator/Generator.py b/grc/core/generator/Generator.py
index f42392e..49731ca 100644
--- a/grc/core/generator/Generator.py
+++ b/grc/core/generator/Generator.py
@@ -17,8 +17,10 @@
 
 
 import codecs
+import datetime
 import os
 import tempfile
+import time
 
 from Cheetah.Template import Template
 
@@ -232,6 +234,8 @@ class TopBlockGenerator(object):
         for var_id in var_ids:
             callbacks[var_id] = [callback for callback in callbacks_all if uses_var_id()]
 
+        build_date = datetime.datetime.utcfromtimestamp(int(os.environ.get('SOURCE_DATE_EPOCH', time.time())))
+
         # Load the namespace
         namespace = {
             'title': title,
@@ -246,6 +250,7 @@ class TopBlockGenerator(object):
             'msgs': msgs,
             'generate_options': self._generate_options,
             'callbacks': callbacks,
+            'build_date': build_date,
         }
         # Build the template
         t = Template(open(FLOW_GRAPH_TEMPLATE, 'r').read(), namespace)
diff --git a/grc/core/generator/flow_graph.tmpl b/grc/core/generator/flow_graph.tmpl
index 5550dca..aa35e6c 100644
--- a/grc/core/generator/flow_graph.tmpl
+++ b/grc/core/generator/flow_graph.tmpl
@@ -30,7 +30,7 @@ $DIVIDER
 #if $flow_graph.get_option('description')
 # Description: $flow_graph.get_option('description')
 #end if
-# Generated: $time.ctime()
+# Generated: $build_date.strftime("%a %b %d %H:%M:%S %Y")
 $DIVIDER
 #if $flow_graph.get_option('thread_safe_setters')
 import threading