Bug#745740: lintian: Please warn on deprecated lzma and bzip2 data.tar members

[Guillem Jover <guillem@debian.org>]

Package: lintian
Version: 2.5.22.1
Severity: wishlist
Tags: patch

Hi!

The lzma and bzip2 compressions are deprecated, and dpkg-deb emits
warnings (since 1.16.4 and 1.17.7 respectively) when trying to build
such packages.

It would be nice to get a warning emitted from lintian, to help in
getting packages using those compression formats being updated.

I've added a new tag uses-deprecated-compression-for-data-tarball for
these, instead of reusing malformed-deb-archive, because these packages
are just fine and will keep being supported at extraction time for the
foreseeable future, even when creating them is disallowed.

I've not tested the patch.

Thanks,
Guillem

From 28319f585317baffae4b2a2912aedbde5c690747 Mon Sep 17 00:00:00 2001
From: Guillem Jover <guillem@debian.org>
Date: Thu, 24 Apr 2014 18:19:49 +0200
Subject: [PATCH] c/deb-format.pm: Warn on deprecated compression formats for
 data.tar

The lzma and bzip2 compressions are deprecated, and dpkg-deb emits
warnings (since 1.16.4 and 1.17.7 respectively) when trying to build
such packages.

We emit the new tag uses-deprecated-compression-for-data-tarball for
these, instead of reusing malformed-deb-archive, because these packages
are just fine and will keep being supported at extraction time for the
foreseeable future, even when creating them is disallowed.

Signed-off-by: Guillem Jover <guillem@debian.org>
---
 checks/deb-format.desc | 12 ++++++++++++
 checks/deb-format.pm   |  3 +++
 2 files changed, 15 insertions(+)

diff --git a/checks/deb-format.desc b/checks/deb-format.desc
index 8a4f214..0d46f20 100644
--- a/checks/deb-format.desc
+++ b/checks/deb-format.desc
@@ -56,3 +56,15 @@ Info: The data tarball of this udeb package is not compressed in format
  .
  Currently, udpkg supports .gz and .xz compressed tarballs.
 
+Tag: uses-deprecated-compression-for-data-tarball
+Severity: important
+Certainty: certain
+Info: The data portion of this binary package uses a deprecated compression
+ format.  Creating such binary packages is supported by dpkg-deb for now,
+ although a warning is emitted for lzma since dpkg 1.16.4 and for bzip2
+ since dpkg 1.17.7, but will eventually be disallowed, although extraction
+ will keep being supported for the foreseeable future.
+ .
+ For lzma, xz is the direct replacement.  For bzip2 either gzip or xz can
+ be used as a substitue, depending on the wanted properties, gzip for
+ maxium compatibility and speed, and xz for maximum compression ratio.
diff --git a/checks/deb-format.pm b/checks/deb-format.pm
index 946b5a9..cc057bd 100644
--- a/checks/deb-format.pm
+++ b/checks/deb-format.pm
@@ -134,8 +134,11 @@ sub run {
                 && $data_member !~ m/^data\.tar\.[gx]z$/) {
                 tag 'udeb-uses-unsupported-compression-for-data-tarball';
             } elsif ($data_member eq 'data.tar.lzma') {
+                tag 'uses-deprecated-compression-for-data-tarball', 'lzma';
                 # Ubuntu's archive allows lzma packages.
                 tag 'lzma-deb-archive';
+            } elsif ($data_member eq 'data.tar.bz2') {
+                tag 'uses-deprecated-compression-for-data-tarball', 'bzip2';
             }
             if (not $okay) {
                 tag 'malformed-deb-archive',
-- 
2.0.0.rc0.280.gacc62aa