Makefile.am AGAIN. grumble...

[cygwin-apps/cygutils.git] / HOW-TO-CONTRIBUTE

So, you have a utility that you believe would 
be a good addition to cygutils, do you?  You 
probably want to know how you could contribute it,
don't you?  Well, first:

  Not every spiffy utility belongs in cygutils. We
  don't want cygutils to become a huge grab bag of
  hundreds of small programs...in many cases, your
  spiffy new program should become a standalone package
  and a full-fledged member of the cygwin distribution.
  (Don't worry -- that's not hard.  It's probably 
  easier than integrating your spiffy program into
  cygutils).

  So, your first step is to post a message to the
  cygwin-apps mailing list, present your program, and 
  ASK if it should be included in cygutils, or turned
  into a standalong package.  If you believe it should
  become part of cygutils, explain why.  I will not
  add any program to cygutils without a consensus
  from the cygwin-apps list.
   
  In the body of your email, describe what your program 
  does, why it's needed, and why you think it should be 
  added to the cygutils package.  Also explain why (or 
  state that) existing tools will not meet the need your 
  program does.

Second, once you're obtained agreement that yourfile.c
should be added to cygutils:

  Don't just send me yourfile.c and expect me to
  do all the integration work.

You need to do more than merely insure that it builds
on your machine with a simple

  gcc -o yourfile.exe yourfile.c -lthislibrary -lthatlibrary

In addition to that, you need to check out the cygutils 
source and integrate yourfile into the whole system.  Instructions
follow below.  However, you'll notice that it's quite a bit
of work.  Again, are you SURE you want it to become part 
of cygutils?  Making a standalone program is a lot easier...

Also, note that I will not fix your bugs.  If, at some time
after your program is accepted into cygutils, I (as cygutils
maintainer) get a bug report on your program, I will forward
it to you.  If you don't fix it or respond within a reasonable
time, I will remove it from the distribution.

------------------------------------------------------

Okay, now that we're past that unpleasantness, here's how to
integrate your spiffy new utility.  First, let's assume that 
your spiffy utility is called 'foo', and its source is in 'foo.c'.

The simple 12 step program:
---------------------------

1) Get the cygutils source

   cvs -d:pserver:anoncvs@sources.redhat.com:/cvs/cygwin-apps login
      use 'anoncvs' as the password
   cvs -z3 -d:pserver:anoncvs@sources.redhat.com:/cvs/cygwin-apps co cygutils

   you now have a 'cygutils' directory with the existing source.

2) License information

   make sure that all .c and .h files in your contribution
   have license information: preferably GPL, but other
   open licenses are acceptable, too.  See the top of
   src/lpr/lpr.c for an example.
	
   a) if your license is not GPL or BSD-no-advert, then
      you must also include a copy of the ENTIRE license
      in the licenses subdirectory.  (Most of the time,
      the blurb in the .c or .h file is just that: a short
      blurb, with a reference to the full text elsewhere)

      You should also add it to the licenses variable in 
      the toplevel Makefile.am: e.g.

      licenses = ... licenses/COPYING.MPL ...

3) Make a home 

   create a new directory for your contribution underneath 'src'
   In our case, we will do this:
     cd cygutils/src
     mkdir foo

   copy your source into the new directory
     cp <location>/foo.c <cygutils>/src/foo/

4) Modify your source code

   Add the following snippet to the beginning of your .c and .h(*) 
   files, just after the license information:

     #if HAVE_CONFIG_H
     #include "config.h"
     #endif
     #include "common.h"
	
   a) If your contribution has its own .h file(s), the entire .h file
      should be "guarded" as follows:
		
        /* license information */
        #ifndef _FOO_H
        #define _FOO_H
        /* the config.h/common.h stuff */
        /* your header stuff */
        #endif /* !_FOO_H */

      the "_FOO_H" identifier should be changed to match the filename
      of your header file.  Thus, "bob.h" would be guarded with _BOB_H.

      Naturally, the header files should also be copied into src/foo/.

5) Modify cygutils/Makefile.am

  a) Add your program to the list of progs to be built.  If your 
     program will build on non-windows platforms in addition to cygwin,
     then you can add your program to the "bin_PROGRAMS" variable:

     bin_PROGRAMS = ... src/foo/foo ...

     If your contribution is windows-specific, then you should add it
     to BOTH the "windows_progs" and the EXTRA_PROGRAMS variables:

     windows_progs = ... src/foo/foo ...
     EXTRA_PROGRAMS = ... src/foo/foo ...

  b) Special link libraries
	
     If you need to link to special *WINDOWS* libraries, then obviously
     your program is windows-specific, but also you should add a line 
     in your Makefile.am like this:

     src_foo_foo_LDADD = -lwinlib

     Where "src_foo_foo" is the path to your program, where the '/' 
     characters are replaced with '_' characters.  Yes, it looks a little
     funny -- but because our subdirectory has the same name as our
     program, we get double foo's...  Also, 'winlib' is the library 
     that you need.  See the src_lpr_lpr_LDADD variable in Makefile.am
     for an example.
	  
     If, on the other hand, you need to link to some other (cygwin)
     library that is also more generally available -- like libreadline
     or libncurses -- then you'll need to do a little more work. 
     For your initial submission, just create an LDADD variable in 
     Makefile.am with -lreadline (or whatever).  We'll figure out how
     to handle it better further down the road.  However, make sure
     to let me know about your special link requirements.

     src_foo_foo_LDADD = -lreadline

     One special case is the gettext internationalization libraries.
     If your program must link with -lintl, then all you need to
     do is create an LDADD variable as follows:

     src_foo_foo_LDADD = @LIBINTL@

     The configuration process will replace @LIBINTL@ with the 
     appropriate -lintl -liconv invocation.

     Note that you do NOT need to include the following libraries in
     a 'src_foo_foo_LDADD' line; these will be added automatically...

     -lcygipc -lpopt  (that is, cygipc or popt)

  c) man pages and other documentation

     If you got 'em, copy 'em to your src/foo directory, and add the
     manpage to the man_MANS variable in Makefile.am like this:

     man_MANS = ... src/foo/foo.1 ...

     If there are non-man-page documentation files, you should those
     files to the extra_docs variable (which gets automatically 
     included in EXTRA_DIST)

     extra_docs = ... src/foo/foo.README ...

     However, there is no provisiion for actually INSTALLING these
     additional documentation files.  At least not yet.

  d) Extra files

     If your contribution consists of more source files than a single
     .c, then you need to add a variable to Makefile.am that lists all 
     of them:

     src_foo_foo_SOURCES = foo.c otherfoo.c foo.h

     Note that this variable should NOT be specified if your program 
     consists merely of a single .c file whose name is the same as
     your program + '.c'.

     If there are .h files in your SOURCES list, then you need to 
     add those .h files to the noinst_HEADERS variable, or the headers 
     would get installed into /usr/include/src/foo/ -- and we don't 
     want that!

     noinst_HEADERS = ... src/foo/foo.h ...

  If you have other questions about the Makefile.am file, try to 
  follow the "patterns" established in it by the other programs, 
  or (gasp) read the automake documentation.

6) Simplify your #includes.

   Take a good look at the #include statements in your .c and .h
   files.  If the dependencies are listed in <cygutils>/common.h,
   then you shouldn't re-include them.  If a dependency is NOT
   listed in common.h, then leave it in your .h/.c file -- for 
   now.  We may choose to add them to common.h and add new tests
   to configure.ac, or we may choose to let your .c file 
   include it directly.  However, anything that's already in 
   common.h, remove from your .c/.h file.  It's okay to just
   comment them out, rather than deleting them entirely, if 
   you prefer.

7) Add information to cygutils documentation files:

   Add a short blurb about your app to <cygutils>/PROGLIST
   Add your app to the list at the end of the README file
   Add your name to the AUTHORS file.

8) Bootstrap

   (You need to have autoconf, autoconf-devel, automake, and
   automake-devel installed for this to work).  Change dir
   to the top of your checked-out source, and run bootstrap:

   cd <cygutils>
   ./bootstrap

   If you haven't made any mistakes, you should (a) see no
   errors, and (b) see some new rules in Makefile.in that
   correspond to your program.

9) Build and test

   Now, just run './configure ; make' as usual.  Somewhere 
   amongst the flurry of messages, you should see your application
   being built.  If so, you're almost done.  If not, then you
   need to figure out why.  Time to read the auto* documentation...

10) Create a patch and ChangeLog entry

   a) PATCH
	
      cd <cygutils>
      cvs diff -u > foo.patch

      If you've already edited the ChangeLog file, make sure to
      *remove* that chunk from foo.patch.  I don't want a PATCH
      for the ChangeLog, I want the ChangeLog entry itself (ChangeLog
      patches rarely apply cleanly; it's easier to cut-n-paste.  More
      below).
  
   b) NEW FILES

      However, you'll notice that none of the files in your src/foo
      directory are represented in the patch.  That's normal.  Remove 
      any .o and .exe files from src/foo, and then just make a tarball

      cd <cygutils>
      tar cvjf foo.tar.bz2 src/foo

   c) CHANGELOG

      You should also create a ChangeLog entry.  Don't actually edit
      the ChangeLog itself; create a new file (foo.changelog?) and
      put your stuff there.  It should look like this:

      2002-03-02  Your Name  <your_email_address@domain.com>

         * src/foo: new directory
         * src/foo/foo.c: new file
         * Makefile.am: add program 'foo'
         * Makefile.in: regenerate
         * AUTHORS: add yourname for foo
         * PROGLIST: add foo
         * README: add foo

      Don't list src/foo/Makefile.  Do list every original
      file in src/foo/ (like your man pages, or extra documentation
      files, or headers)

11) Send a notice email to cygwin-apps@cygwin.com, that says "Hey, I
   finished the integration work neceesary to include 'foo' in the
   'cygutils' package, as previously agreed on this list."  Paste 
   the ChangeLog into that notice.  But do NOT send the patch or 
   tarball to the mailing list.  
	
   Instead, send that to ME, cwilson@ece.gatech.edu.  The patch
   and tarball should be attachments, but paste the ChangeLog entry
	into the body of the message.  Do NOT paste your patch into the 
	body of the email; most mail programs will horrendously distort 
   it if you do).  Also, be sure and warn of any special link 
   requirements (cf. section 5a and 5b above).

12) Bask in the glow of a job well done.

--
Chuck Wilson
cygutils maintainer

Note to self: how to commit contributions:
  apply the patch
  untar the contribution
  Add the Changelog entry
  ./bootstrap
  cvs add src/directory
  cvs add src/directory/srcfiles
  cvs commit -m "Add foo contribution"
  ./bootstrap
  cvs diff | grep Index > foo
  >>> use 'foo' to add another Changelog entry
  cvs commit -m "Add foo contribution"
  cvs tag something