Archive for August, 2010

Packaging a java library for Debian as an upstream

Tuesday, August 17th, 2010

I have just finished my GSoC project working on GNU Prolog for Java which is a Java library for doing Prolog. I got as far as the beta release of version 0.2.5. One of the things I want to do for the final release is to integrate the making of .deb files to distribute the binary, source and documentation into the ant build system. This post exists to chronicle how I go about doing that.

First some background reading: There is a page on the debian wiki on Java Packaging. You will want to install javahelper as well as debain-policy and debhelper. You will then have the javahelper documentation in /usr/share/doc/javahelper/. The debian policy on java will probably also be useful.

Now most debian packages will be created by people working for debian using the releases made by upstreams but I want to be a good upstream and do it myself.

So I ran:

jh_makepkg --package=gnuprologjava --maintainer="Daniel Thomas" \
    --email="drt24-debian@srcf.ucam.org" --upstream="0.2.5" --library --ant --default

I then reported a bug in jh_makepkg where it fails to support the --default and --email options properly because I got “Invalid option: default”. Which might be fixed by the time you read this.
So I ran:

jh_makepkg --package=gnuprologjava --maintainer="Daniel Thomas" \
    --email="drt24-debian@srcf.ucam.org" --upstream="0.2.5" --library --ant

And selected ‘default’ when prompted by pressing F.
I got:

dch warning: Recognised distributions are:
{dapper,hardy,intrepid,jaunty,karmic,lucid,maverick}{,-updates,-security,-proposed,-backports} and UNRELEASED.
Using your request anyway.
dch: Did you see that warning?  Press RETURN to continue...

Which I think stems from the fact that javahelper is assuming debian but javahelper uses debhelper or similar which Ubuntu has configured for Ubuntu. However this doesn’t matter to me as I am trying to make a .deb for Debian (as it will then end up in Ubuntu and many other places – push everything as far upstream as possible).
Now because of the previously mentioned bug the --email option is not correctly handled so we need to fix changelog, control and copyright in the created debian folder to use the correct email address rather than user@host in the case of changelog and NAME in the case of control and copyright (two places in copyright).

copyright needs updating to have Upstream Author, Copyright list and licence statement and homepage.
For licence statement I used:

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 3 of the License, or (at your option) any later version.

    This library 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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA  02110-1301 USA

On Debian systems the full text of the GNU Library Public License, can be
found in the file /usr/share/common-licenses/LGPL-3.

control needs updating to add homepage, Short Description and Long Description (which needs to be indented with one space). I also added texinfo and libgetopt-java to Build-Depends and Suggests: libgetopt-java.
GNU Prolog for Java has a build dependency on gnu.getopt as gnu.prolog.test.GoalRunner uses it so I added
export CLASSPATH=/usr/share/java/gnu-getopt.jar to debian/rules. libgnuprologjava-java.javadoc needed build/api put in it so that it could find the javadoc.

So at this point I have a debian folder with the right files in it but I don’t have an ant task which will do everything neatly. Since debian package building really wants to happen on an unpacked release tarball of the source I modified my existing dist-src target to copy the debian folder across as well and added the following to my init target:

<!-- Key id to use for signing the .deb files -->
<property name="dist.keyid" value="" />
<property name="dist.name-version" value="${ant.project.name}-${version}"/>
<property name="dist.debdir" value="dist/${dist.name-version}/" />

I could then add the following dist-deb target to do all the work.

<target name="dist-deb" depends="dist-src" description="Produce a .deb to install with">
	<mkdir dir="${dist.debdir}"/>
	<unzip src="dist/${dist.name-version}-src.zip" dest="${dist.debdir}"/>
	<!-- Delete the getopt code as we want to use the libgetopt-java package for that -->
	<delete dir="${dist.debdir}src/gnu/getopt"/>
	<exec executable="dpkg-buildpackage" dir="${dist.debdir}">
		<arg value="-k${dist.keyid}"/>
	</exec>
</target>

So this gives me binary and source files for distribution and includes the javadoc documentation but lacks the manual.
To fix that I added libgnuprologjava-java.docs containing

build/manual/
docs/readme.txt

, libgnuprologjava-java.info containing build/gnuprologjava.info and libgnuprologjava-java.doc-base.manual containing:

Document: libgnuprologjava-java-manual
Title: Manual for libgnuprologjava-java
Author: Daniel Thomas
Abstract: This the Manual for libgnuprologjava-java
Section: Programming

Format: HTML
Index: /usr/share/doc/libgnuprologjava-java/manual
Files: /usr/share/doc/libgnuprologjava-java/manual/*.html

Now all of this might result in the creation of the relevant files needed to get GNU Prolog for Java into Debian but then again it might not :-). The .deb file does install (and uninstall) correctly on my machine but I might have violated some debian-policy.

Compiling git from git fails if core.autocrlf is set to true

Monday, August 16th, 2010

If you get the following error when compiling git from a git clone of git:

: command not foundline 2: 
: command not foundline 5: 
: command not foundline 8: 
./GIT-VERSION-GEN: line 14: syntax error near unexpected token `elif'
'/GIT-VERSION-GEN: line 14: `elif test -d .git -o -f .git &&
make: *** No rule to make target `GIT-VERSION-FILE', needed by `git-am'. Stop.
make: *** Waiting for unfinished jobs....

and you have core.autocrlf set to true in your git config then consider the following “it’s probably not a good idea to convert newlines in the git repo” curtsey of wereHamster on #git.

So having core.autocrlf set to true may result in bad things happening in odd ways because line endings are far more complicated than they have any reason to be (thanks to decisions made before I was born). Bugs due to white space errors are irritating and happen to me far too often :-).

Today I used CVS – it was horrible, I tried to use git’s cvsimport and cvsexportcommit to deal with the fact that CVS is horrible unfortunately this did not work ;-(.

This post exists so that the next time someone is silly like me they might get a helpful response from Google.