[mmh] / docs / README.developers

#
# README.developers
#

This file is intended to provide a few tips for anyone doing development on nmh.
Developers who learn things "the hard way" about the nmh codebase (as opposed to
local info best encoded in a comment) are encouraged to share their wisdom here.

The topics are organized alphabetically.


--------------
autoconf files
--------------

If you wish to change the `configure' script or its related files, you'll need
to first install GNU m4, available from <ftp://ftp.gnu.org/pub/gnu/m4/> and then
GNU autoconf (<ftp://ftp.gnu.org/pub/gnu/autoconf/>).  Nmh is currently using
a minimum of autoconf 2.61.

Most of the configure-related files are automatically generated.  The only files
you should need to manually edit are acconfig.h and configure.ac.  Don't, for
instance, edit config.h.in.  Though it is an input file from the point of view
of the users (and the configure script) it is an output file from the point of
view of the developers (and the autoconf script).

Note that the automatically generated autoconf files (such as config.h.in,
stamp-h.in, and configure), are NOT kept in git.  Thus, when you check out
a git tree, you need to run the autogen.sh script before you can build
anything:

        % ./autogen.sh

-------------------
directory structure
-------------------

Following is a list of nmh's directories along with a brief description of the
purpose of each one.  Meanings are given for the abbreviations, but note that
these meanings are just informed guesses as to what the MH developers were
thinking.

./
    The top-level directory.  Contains files like README and INSTALL.

config/
    Contains utility files for the `configure' process.  Ordinarily nothing in
    here needs to be messed with.

docs/
    Contains more specialized documentation, such as this file and
    the FAQ.

etc/
    Contains files, file templates, and scripts to generate files that will be
    installed in the ${prefix}/etc directory.  Stuff like replcomps.

h/
    Most of nmh's header (.h) files are kept not in the individual source
    directories, but in this central location.

man/
    Contains all the input files that are processed to generate nmh's manual
    pages.

sbr/
    "sbr" stands for "subroutine(s)".  For the most part, each source file in
    this directory contains a single function with the same name as the source
    file.  These functions are of general use and are called from throughout
    nmh.

uip/
    "uip" stands for "User Interface Programs".  Most nmh commands have a file
    in this directory named <command>.c containing the code for that command
    (e.g. repl.c).  In some cases there is also an auxiliary file called
    <command>sbr.c which contains additional subroutines called from <command>.c
    (which would contain not much else besides main()).


---
git
---

As of December 2010, nmh has switched to using git for revision control
instead of CVS.  While the topic of git is beyond the scope of this FAQ,
to get started with git & nmh, you can run the following command to checkout
the nmh repository:

    % git clone git://git.savannah.nongnu.org/nmh.git

That will create a workspace called nmh. To update that workspace
with changes to the master, cd to it and run:

    % git pull


-------------------------------------------------------
nmh-local functions to use in preference to OS versions
-------------------------------------------------------

For some system functions whose availability or behavior varies from OS to OS,
nmh conditionally uses a local definition with the same name as the OS function
(e.g. snprintf()).  For other functions, developers need to avoid the OS
versions and always use the nmh-supplied function.  Here is a list of such
functions:

OS function  nmh-local version to use instead
===========  ================================
getpass()    nmh_getpass()


-------------
releasing nmh
-------------

To make a public release of nmh (we'll use version 1.0.4 as examples
here; the convention for release candidates is to use something like
"1.0.4-RC1"):

 1. % echo 1.0.4 > VERSION
    % date +"%e %B %Y" > DATE
    (DATE should contain something like "30 December 2000")

 2. % git commit VERSION DATE; git push

 3. % git tag -a nmh-1_0_4 -m 'Releasing nmh-1_0_4.'

 4. % make nmhdist

 5. Untar nmh-1.0.4.tar.gz and `diff -r' it vs. your workspace.  Make
    sure no files got left out of the distribution that should be in it
    (due to someone forgetting to update the DIST variables in the
    Makefiles).

 6. If you have root access on your machine, it's good at this point to do:

    % chown -R 0:0 nmh-1.0.4
    % tar cvf nmh-1.0.4.tar nmh-1.0.4
    % gzip nmh-1.0.4.tar

    If you leave the files in the archive as being owned by yourself, your UID
    may coincide with one of a user on a machine where nmh is being installed,
    making it possible for that user to Trojan the nmh code before the system
    administrator finishes installing it.

 7. Make sure your new tarball uncompresses and untars with no problem.  Make
    sure you can configure, make, and install nmh from it.

 8. If all is well and your tarball is final, go back to your workspace and do:

    % echo 1.0.4+dev > VERSION

 9. % git commit VERSION; git push

10. If possible, make an MD5 hash and/or a PGP signature of nmh-1.0.4.tar.gz.
    Assuming you have gpg set up, this should be:
    % gpg --output nmh-1.0.4.tar.gz.sig --detach-sig nmh-1.0.4.tar.gz

    You can verify the signature with
    % gpg --verify nmh-1.0.4.tar.gz.sig nmh-1.0.4.tar.gz

11. Upload the files to savannah. First make sure they are mode 664 so
    they will have the right permissions on the server end
    (see https://savannah.gnu.org/maintenance/SharedDownloadArea)
    % chmod 664 nmh-1.0.4.tar.gz*

    Then scp them across:
    % scp -p nmh-1.0.4.tar.gz* youruser@dl.sv.nongnu.org:/releases/nmh/

12. Update the http://www.nongnu.org/nmh/ homepage. (It lives in the CVS
    'webpages repository'; see https://savannah.nongnu.org/cvs/?group=nmh)

13. Add a news item to the savannah nmh page. You'll have to submit it first
    and then separately approve it (under News->Manage).

14. Send the release announcement email to the following places:
     nmh-workers@nongnu.org
     nmh-announce@nongnu.org
     exmh-users@redhat.com
     exmh-workers@redhat.com
     mh-e-users@lists.sourceforge.net
     mh-users@ics.uci.edu *or* comp.mail.mh (there is a bidirectional gateway)

    If the release fixes significant security holes, also send an announcement
    to bugtraq@securityfocus.com.  The exmh lists require you to be subscribed
    in order to post.  Note that you don't need to post separately to
    comp.mail.mh, as the mh-users mailing list is apparently bidirectionally
    gatewayed to it.

    Preferably, the announcement should contain the MD5 hash generated above,
    and should be PGP-signed.  It should include the URL for the tarball as
    well as the URL of the website.  It should contain a brief summary of
    visible changes, as well as the URL of the git diff page that would show
    a detailed list of changes.  The changes between 1.5 and 1.4 would be
    shown by [this is just a guess, I don't know anything about cgit, and
    it assumes that we tag with nmh-x_x-release from now on]:

        http://git.savannah.gnu.org/cgit/nmh.git/diff/?h=nmh-1_5-release?h=nmh-1_4-release