HACKING

   1 Here are some guidelines for working on the Guile source tree at GNU.
   2
   3 - We use CVS to manage the Guile sources.  The repository lives on
   4 totoro.red-bean.com, in /u/src/master; you will need an account on
   5 that machine to access the repository.  I recommend using the cvs
   6 pserver protocol; thus, you should use the following as your CVS root:
   7
   8         :pserver:USER@guile-cvs.red-bean.com:/u/src/master
   9
  10 Either set your CVSROOT environment variable to that, or give it as
  11 the value of the global -d option to CVS when you check out a working
  12 directory.
  13
  14 If you want to use SSH for security, set your CVS_RSH environment
  15 variable to ssh, and then use the following as your CVS root:
  16
  17         :ext:guile-cvs.red-bean.com:/u/src/master
  18
  19 The Guile sources live in several modules:
  20
  21   - guile-core --- the interpreter, QuickThreads, and ice-9
  22   - guile-tcltk --- the Guile/Tk interface
  23   - guile-rgx-ctax --- the Guile/Rx interface, and the ctax implementation
  24   - guile-scsh --- the port of SCSH to guile, talk to Gary Houston
  25   - guile --- the old Guile module, containing everything.  The only portion
  26     of this anyone should edit is the newdoc subdirectory.  Everything
  27     else is out of date.  We'll get rid of this soon.
  28
  29 - As for any part of Project GNU, changes to Guile should follow the
  30 GNU coding standards.  The standards are available via anonymous FTP
  31 from prep.ai.mit.edu, as /pub/gnu/standards/standards.texi and
  32 make-stds.texi.
  33
  34 - Check Makefile.in and configure files into CVS, as well as any files
  35 used to create them (Makefile.am, configure.in); don't check in
  36 Makefiles or header files generated by configuration scripts.  The
  37 general rule is that you should be able to check out a working
  38 directory of Guile from CVS, and then type "configure" and "make".
  39
  40 - Make sure your changes compile and work, at least on your own
  41 machine, before checking them into the main branch of the Guile
  42 repository.  If you really need to check in untested changes, make a
  43 branch.
  44
  45 - When you make a user-visible change (i.e. one that should be
  46 documented, and appear in NEWS, put an asterisk in column zero of the
  47 start of the ChangeLog entry, like so:
  48
  49 Sat Aug  3 01:27:14 1996  Gary Houston  <ghouston@actrix.gen.nz>
  50
  51 *       * fports.c (scm_open_file): don't return #f, throw error.
  52
  53 When you've written a NEWS entry and updated the documentation, go
  54 ahead and remove the asterisk.  I will use the asterisks to find and
  55 document changes that haven't been dealt with before a release.
  56
  57 - Include each log entry in both the ChangeLog and in the CVS logs.
  58 If you're using Emacs, the pcl-cvs interface to CVS has features to
  59 make this easier; it checks the ChangeLog, and generates good default
  60 CVS log entries from that.
  61
  62 - There's no need to keep a change log for documentation files.  This
  63 is because documentation is not susceptible to bugs that are hard to
  64 fix.  Documentation does not consist of parts that must interact in a
  65 precisely engineered fashion; to correct an error, you need not know
  66 the history of the erroneous passage.  (This is copied from the GNU
  67 coding standards.)
  68
  69 - If you add or remove files, don't forget to update the appropriate
  70 part of the relevant Makefile.am files, and regenerate the
  71 Makefile.in.  If you forget this, the snapshot and distribution
  72 processes will not work.
  73
  74 - Make sure you have papers from people before integrating their
  75 changes or contributions.  This is very frustrating, but very
  76 important to do right.  From maintain.texi, "Information for
  77 Maintainers of GNU Software":
  78
  79     When incorporating changes from other people, make sure to follow the
  80     correct procedures.  Doing this ensures that the FSF has the legal
  81     right to distribute and defend GNU software.
  82
  83     For the sake of registering the copyright on later versions ofthe
  84     software you need to keep track of each person who makes significant
  85     changes.  A change of ten lines or so, or a few such changes, in a
  86     large program is not significant.
  87
  88     *Before* incorporating significant changes, make sure that the person
  89     has signed copyright papers, and that the Free Software Foundation has
  90     received them.
  91
  92 If you receive contributions you want to use from someone, let me know
  93 and I'll take care of the administrivia.  Put the contributions aside
  94 until we have the necessary papers.
  95
  96 - When you make substantial changes to a file, add the current year to
  97 the list of years in the copyright notice at the top of the file.
  98
  99 - [From Mikael Djurfeldt] When working on the Guile internals, it is
 100 quite often practical to implement a scheme-level procedure which
 101 helps you examine the feature you're working on.
 102
 103 Examples of such procedures are: pt-size, debug-hand and
 104 current-pstate.
 105
 106 I've now put #ifdef GUILE_DEBUG around all such procedures, so that
 107 they are not compiled into the "normal" Guile library.  Please do the
 108 same when you add new procedures/C functions for debugging purpose.
 109
 110 You can define the GUILE_DEBUG flag by passing --enable-guile-debug to
 111 the configure script.
 112
 113
 114 Jim Blandy