3 Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2008 Free software Foundation, Inc.
5 Permission is granted to anyone to make or distribute verbatim copies
6 of this document as received, in any medium, provided that the
7 copyright notice and permission notice are preserved,
8 and that the distributor grants the recipient permission
9 for further redistribution as permitted by this notice.
11 Permission is granted to distribute modified versions
12 of this document, or of portions of it,
13 under the above conditions, provided also that they
14 carry prominent notices stating who last changed them,
15 and that any new or changed statements about the activities
16 of the Free Software Foundation are approved by the Foundation.
19 What to Hack =========================================================
21 You can hack whatever you want, thank GNU.
23 However, to see what others have indicated as their interest (and avoid
24 potential wasteful duplication of effort), see file TODO. Note that
25 the version you find may be out of date; a CVS checkout is recommended:
26 see below for details (see also the files ANON-CVS and SNAPSHOTS).
28 It's also a good idea to join the guile-devel@gnu.org mailing list.
29 See http://www.gnu.org/software/guile/mail/mail.html for more info.
32 Hacking It Yourself ==================================================
34 When Guile is obtained from CVS, a few extra steps must be taken
35 before the usual configure, make, make install. You will need to have
36 up-to-date versions of the tools listed below, correctly installed.
37 i.e., they must be found in the current PATH and not shadowed or
38 otherwise broken by files left behind from other versions.
40 "up-to-date" means the latest released versions at the time that Guile
41 was obtained from CVS. Sometimes older or newer versions will work.
42 (See below for versions to avoid.)
44 Then you must run the autogen.sh script, as described below.
46 In case of problems, it may be worth getting a fresh copy of Guile
47 from CVS: synchronisation problems have been known to occur
50 The same procedure can be used to regenerate the files in released
51 versions of Guile. In that case the headers of the original generated
52 files (e.g., configure, Makefile.in, ltmain.sh) can be used to
53 identify which tool versions may be required.
55 Autoconf --- a system for automatically generating `configure'
56 scripts from templates which list the non-portable features a
57 program would like to use. Available in
58 "ftp://ftp.gnu.org/pub/gnu/autoconf"
60 Automake --- a system for automatically generating Makefiles that
61 conform to the (rather Byzantine) GNU coding standards. The
62 nice thing is that it takes care of hairy targets like 'make
63 dist' and 'make distclean', and automatically generates
64 Makefile dependencies. Automake is available in
65 "ftp://ftp.gnu.org/pub/gnu/automake"
67 libtool --- a system for managing the zillion hairy options needed
68 on various systems to produce shared libraries. Available in
69 "ftp://ftp.gnu.org/pub/gnu/libtool". Version 1.5.26 (or
70 later) is needed for correct AIX support.
72 gettext --- a system for rigging a program so that it can output its
73 messages in the local tongue. Guile presently only exports
74 the gettext functionality to Scheme, it does not use it
77 flex --- a scanner generator. It's probably not essential to have the
80 One false move and you will be lost in a little maze of automatically
81 generated files, all different.
83 Here is the authoritative list of tool/version/platform tuples that
84 have been known to cause problems, and a short description of the problem.
86 - automake 1.4 adds extraneous rules to the top-level Makefile if
87 you specify specific Makefiles to rebuild on the command line.
89 - automake 1.4-p4 (debian "1:1.4-p4-1.1") all platforms
90 automake "include" facility does not recognize filenames w/ "-".
92 - libtool 1.4 uses acconfig.h, which is deprecated by newest autoconf
93 (which constructs the equivalent through 3rd arg of AC_DEFINE forms).
95 - autoreconf from autoconf prior to 2.59 will run gettextize, which
96 will mess up the Guile tree.
101 Sample GDB Initialization File=========================================
103 Here is a sample .gdbinit posted by Bill Schottstaedt (modified to
104 use `set' instead of `call' in some places):
111 Executes (object->string arg)
116 call gdb_eval(gdb_result)
117 set gdb_print(gdb_result)
121 Executes (print (eval (read arg))): ge "(+ 1 2)" => 3
125 call g_help(scm_str2symbol($arg0), 20)
130 Prints help string for arg: gh "enved-target"
135 so in gdb if you see something useless like:
137 #32 0x081ae8f4 in scm_primitive_load (filename=1112137128) at load.c:129
139 You can get the file name with gp:
142 $1 = 0x40853fac "\"/home/bil/test/share/guile/1.5.0/ice-9/session.scm\""
145 Contributing Your Changes ============================================
147 - If you have put together a change that meets the coding standards
148 described below, we encourage you to submit it to Guile. The best
149 place to post it is guile-devel@gnu.org. Please don't send it
150 directly to me; I often don't have time to look things over. If you
151 have tested your change, then you don't need to be shy.
153 - Please submit patches using either context or unified diffs (diff -c
154 or diff -u). Don't include a patch for ChangeLog; such patches don't
155 apply cleanly, since we've probably changed the top of ChangeLog too.
156 Instead, provide the unaltered text at the top of your patch.
158 - For proper credit, also make sure you update the AUTHORS file
159 (for new files for which you've assigned copyright to the FSF), or
160 the THANKS file (for everything else).
162 Please don't include patches for generated files like configure,
163 aclocal.m4, or any Makefile.in. Such patches are often large, and
164 we're just going to regenerate those files anyway.
167 CVS conventions ======================================================
169 - We use CVS to manage the Guile sources. The repository lives on
170 subversions.gnu.org, in /cvs; you will need an
171 account on that machine to access the repository. Also, for security
172 reasons, subversions presently only supports CVS connections via the SSH
173 protocol, so you must first install the SSH client. Then, you should
174 set your CVS_RSH environment variable to ssh, and use the following as
177 :ext:USER@subversions.gnu.org:/cvs
179 Either set your CVSROOT environment variable to that, or give it as
180 the value of the global -d option to CVS when you check out a working
183 For more information on SSH, see http://www.openssh.com.
185 The Guile sources live in several modules:
187 - guile-core --- the interpreter, QuickThreads, and ice-9
188 - guile-tcltk --- the Guile/Tk interface
189 - guile-tk --- the new Guile/Tk interface, based on STk's modified Tk
190 - guile-rgx-ctax --- the Guile/Rx interface, and the ctax implementation
191 - guile-scsh --- the port of SCSH to guile, talk to Gary Houston
192 - guile-www --- A Guile module for making HTTP requests.
193 - guile-statprof --- an experimental statistical profiler.
195 There is a mailing list for CVS commit messages; see README for details.
197 - The guile-core tree is now versioned similarly to the Linux kernel.
198 Guile now always uses three numbers to represent the version,
199 i.e. "1.6.5". The first number, 1, is the major version number, the
200 second number, 6, is the minor version number, and the third number,
201 5, is the micro version number. Changes in major version number
202 indicate major changes in Guile.
204 Minor version numbers that are even denote stable releases, and odd
205 minor version numbers denote development versions (which may be
206 unstable). The micro version number indicates a minor sub-revision of
207 a given MAJOR.MINOR release.
209 - A default CVS checkout will get the current unstable development
210 tree. However, for each stable release, a CVS branch is created so
211 that release (and ongoing maintenance) of the stable version can
212 proceed independent of the development of the next unstable version.
213 To check out a particular stable branch, you just need to specify "-r
214 branch_release-X-Y" to your CVS checkout command (or to any update).
215 For example, if you wanted to check out the 1.6 stable branch, you
216 would specify "-r branch_release-1-6".
218 So, for example, during a normal development cycle, work will proceed
219 on an unstable version, say 1.5.X, until it is decided that it's time
220 for a stable release. At that point, a branch named
221 branch_release-1-6 will be created, and the version numbers on the
222 HEAD of the CVS tree (the trunk, i.e. what you get by default), will
223 be changed to reflect the new unstable version 1.7.X. Then unstable
224 development will proceed on the unstable version, while the stable
225 1.5.X branch is fixed up for the eventual 1.6.0 release.
227 Anytime you want to yank an existing checked out tree to the stable
228 branch, you can run a command like this:
230 cvs -z3 update -r branch_release-1-6 -Pd
232 This will yank the working directory over on to the stable release
233 branch. Note that this directory will track that branch from then on
234 unless you do something to yank it back to the main (unstable) trunk.
236 To go back to the unstable branch, you can use
238 cvs -z3 update -A -Pd
240 Note that in either case, you should probably make sure you've
241 commited or removed all local changes before running the commands or
242 you're likely to have some unexpected results.
244 Finally note that one approach, should you need to work on both
245 branches, is to keep two trees checked out, one stable, the other
246 unstable and you can work in whichever is appropriate.
248 To save some initial bandwidth, you can check out either the stable
249 tree or the unstable tree, and then do something like this:
251 cp -a core-unstable core-1.5
253 cvs -z3 update -r branch_release-1-6 -Pd
255 - The stable and unstable CVS trees are distinct, and no changes will
256 automatically propagate between them. If you make changes that need
257 to show up both places, you'll need to apply the changes both places.
258 You *might* be able to do this with a cvs command, but often you'll
259 probably need to apply the changes by hand or risk migrating
260 superfluous modifications between the two versions. This is
261 particularly important when moving a change from the unstable branch
262 to the stable branch.
264 - In general, please don't be adventurous with the stable branch. We
265 mostly want bugfixes, documentation improvements, build improvements,
266 etc., though exceptions will doubtless exist.
268 - There are a few CVS tagging conventions which follow the Scheme
269 convention that dashes are used to separate words within a single
270 symbol, and so dashes bind more tightly than underscores. This means
271 that foo-bar_baz-bax indicates that foo-bar is somehow separate from
272 baz-bax. The conventions are as follows:
276 anytime just before you create a branch it's a good
277 idea to create a normal tag so that you can refer to the branch point
278 on the main trunk as well as on the branch. So please use a tag of
281 branch-root-release-1-X
283 or more generally, for other non-release branches:
289 for the branch tag itself please use
293 or more generally, for other non-release branches:
299 Whenever you're merging a branch back into the trunk (or into another
300 branch repeatedly) you need to tag the branch each time you merge. If
301 you don't do that, you won't be able to merge repeatedly without
302 possibly tedious conflicts. For those tags, we suggest:
304 branch-merge_SOME-FOO_to_SOME-BAR_1
305 branch-merge_SOME-FOO_to_SOME-BAR_2
308 As an example, SOME-BAR might be trunk, or even perhaps another branch
309 like branch-mvo-super-fixes :>
311 More mundanely, you might have
313 branch-merge_release-1-6_to_trunk_1
315 (Merging the stable branch to the trunk like this
316 will probably be much more common, when it happens, than the
317 reverse for the reasons mentioned above.
321 When releasing a new version of guile, please use:
329 - If you hack on a stable branch, please apply any relevant patches or
330 fixes to the current unstable version (the main CVS trunk) as well.
331 Similarly, please back-port any important fixes to the unstable CVS
332 tree to the current stable branch.
334 - We check Makefile.am and configure.in files into CVS, but the
335 "autogen.sh" script must be run from the top-level to generate the
336 actual "configure" script that then must be run to create the various
337 Makefile-s to build guile. The general rule is that you should be able
338 to check out a working directory of Guile from CVS, and then type
339 "./autogen.sh", then "configure", and finally "make". No
340 automatically generated files should be checked into the CVS
343 - The .cvsignore file is contained in the repository, to provide a
344 reasonable list of auto-generated files that should not be checked in.
345 This, however, prohibits one from having local additions to the
346 .cvsignore file (yes, you can modify it and never check it in, but
347 that doesn't seem to be a good solution to me). To get around this
348 problem, you might want to patch your cvs program so that it uses a
349 .cvsignore-local file (say) instead of the one from the repository. A
350 patch for this can be found at the very end of this file.
352 - (Automake 1.4 only) Be sure to run automake at the top of the tree
353 with no arguments. Do not use `automake Makefile' to regenerate
354 specific Makefile.in files, and do not trust the Makefile rules to
355 rebuild them when they are out of date. Automake 1.4 will add
356 extraneous rules to the top-level Makefile if you specify specific
357 Makefiles to rebuild on the command line. Running the command
358 `autoreconf --force' should take care of everything correctly.
360 - Make sure your changes compile and work, at least on your own
361 machine, before checking them into the main branch of the Guile
362 repository. A good way for testing this is to run "make distcheck".
363 If you really need to check in untested changes, make a branch.
365 - Include each log entry in both the ChangeLog and in the CVS logs.
366 If you're using Emacs, the pcl-cvs interface to CVS has features to
367 make this easier; it checks the ChangeLog, and generates good default
368 CVS log entries from that.
371 Coding standards =====================================================
373 - Before contributing larger amounts of code to Guile, please read the
374 documents in `guile-core/devel/policy' in the CVS source tree.
376 - As for any part of Project GNU, changes to Guile should follow the
377 GNU coding standards. The standards are available via anonymous FTP
378 from prep.ai.mit.edu, as /pub/gnu/standards/standards.texi and
381 - The Guile tree should compile without warnings under the following
382 GCC switches, which are the default in the current configure script:
384 -O2 -Wall -Wpointer-arith -Wmissing-prototypes
386 To make sure of this, you can use the --enable-error-on-warning option
387 to configure. This option will make GCC fail if it hits a warning.
389 Note that the warnings generated vary from one version of GCC to the
390 next, and from one architecture to the next (apparently). To provide
391 a concrete common standard, Guile should compile without warnings from
392 GCC 2.7.2.3 in a Red Hat 5.2 i386 Linux machine. Furthermore, each
393 developer should pursue any additional warnings noted by on their
394 compiler. This means that people using more stringent compilers will
395 have more work to do, and assures that everyone won't switch to the
396 most lenient compiler they can find. :)
398 Note also that EGCS (as of November 3 1998) doesn't handle the
399 `noreturn' attribute properly, so it doesn't understand that functions
400 like scm_error won't return. This may lead to some silly warnings
401 about uninitialized variables. You should look into these warnings to
402 make sure they are indeed spurious, but you needn't correct warnings
403 caused by this EGCS bug.
405 - If you add code which uses functions or other features that are not
406 entirely portable, please make sure the rest of Guile will still
407 function properly on systems where they are missing. This usually
408 entails adding a test to configure.in, and then adding #ifdefs to your
409 code to disable it if the system's features are missing.
411 - The normal way of removing a function, macro or variable is to mark
412 it as "deprecated", keep it for a while, and remove it in a later
413 release. If a function or macro is marked as "deprecated" it
414 indicates that people shouldn't use it in new programs, and should try
415 to remove it in old. Make sure that an alternative exists unless it
416 is our purpose to remove functionality. Don't deprecate definitions
417 if it is unclear when they will be removed. (This is to ensure that a
418 valid way of implementing some functionality always exists.)
420 When deprecating a definition, always follow this procedure:
422 1. Mark the definition using
424 #if (SCM_DEBUG_DEPRECATED == 0)
428 or, for Scheme code, wrap it using
433 2. Make the deprecated code issue a warning when it is used, by using
434 scm_c_issue_deprecation_warning (in C) or issue-deprecation-warning
437 3. Write a comment at the definition explaining how a programmer can
438 manage without the deprecated definition.
440 4. Add an entry that the definition has been deprecated in NEWS and
441 explain what do do instead.
443 5. In file TODO, there is a list of releases with reminders about what
444 to do at each release. Add a reminder about the removal of the
445 deprecated defintion at the appropriate release.
447 - Please write log entries for functions written in C under the
448 functions' C names, and write log entries for functions written in
449 Scheme under the functions' Scheme names. Please don't do this:
451 * procs.c, procs.h (procedure-documentation): Moved from eval.c.
453 Entries like this make it harder to search the ChangeLogs, because you
454 can never tell which name the entry will refer to. Instead, write this:
456 * procs.c, procs.h (scm_procedure_documentation): Moved from eval.c.
458 Changes like adding this line are special:
460 SCM_PROC (s_map_in_order, "map-in-order", 2, 0, 1, scm_map);
462 Since the change here is about the name itself --- we're adding a new
463 alias for scm_map that guarantees the order in which we process list
464 elements, but we're not changing scm_map at all --- it's appropriate
465 to use the Scheme name in the log entry.
467 - There's no need to keep a change log for a ChangeLog file. For any
468 other kind of file (including documentation, since our documentation
469 is indeed precisely engineered -- we surpass GNU standards here), add
470 an appropriate ChangeLog entry when you change it. Simple!
472 - Make sure you have papers from people before integrating their
473 changes or contributions. This is very frustrating, but very
474 important to do right. From maintain.texi, "Information for
475 Maintainers of GNU Software":
477 When incorporating changes from other people, make sure to follow the
478 correct procedures. Doing this ensures that the FSF has the legal
479 right to distribute and defend GNU software.
481 For the sake of registering the copyright on later versions ofthe
482 software you need to keep track of each person who makes significant
483 changes. A change of ten lines or so, or a few such changes, in a
484 large program is not significant.
486 *Before* incorporating significant changes, make sure that the person
487 has signed copyright papers, and that the Free Software Foundation has
490 If you receive contributions you want to use from someone, let me know
491 and I'll take care of the administrivia. Put the contributions aside
492 until we have the necessary papers.
494 Once you accept a contribution, be sure to keep the files AUTHORS and
497 - When you make substantial changes to a file, add the current year to
498 the list of years in the copyright notice at the top of the file.
500 - When you get bug reports or patches from people, be sure to list
504 Naming conventions =================================================
506 We use certain naming conventions to structure the considerable number
507 of global identifiers. All identifiers should be either all lower
508 case or all upper case. Syllables are separated by underscores `_'.
509 All non-static identifiers should start with scm_ or SCM_. Then might
510 follow zero or more syllables giving the category of the identifier.
511 The currently used category identifiers are
515 c,C - something with a interface suited for C use. This is used
516 to name functions that behave like Scheme primitives but
517 have a more C friendly calling convention.
519 i,I - internal to libguile. It is global, but not considered part
522 f - a SCM variable pointing to a Scheme function object.
524 F - a bit mask for a flag.
526 m - a macro transformer procedure
528 n,N - a count of something
530 s - a constant C string
532 k - a SCM variable pointing to a keyword.
534 sym - a SCM variable pointing to a symbol.
536 var - a SCM variable pointing to a variable object.
538 The follwing syllables also have a technical meaning:
540 str - this denotes a zero terminated C string
542 mem - a C string with an explicit count
545 See also the file `devel/names.text'.
548 Helpful hints ========================================================
550 - [From Mikael Djurfeldt] When working on the Guile internals, it is
551 quite often practical to implement a scheme-level procedure which
552 helps you examine the feature you're working on.
554 Examples of such procedures are: pt-size, debug-hand and
557 I've now put #ifdef GUILE_DEBUG around all such procedures, so that
558 they are not compiled into the "normal" Guile library. Please do the
559 same when you add new procedures/C functions for debugging purpose.
561 You can define the GUILE_DEBUG flag by passing --enable-guile-debug to
562 the configure script.
564 - You'll see uses of the macro SCM_P scattered throughout the code;
565 those are vestiges of a time when Guile was meant to compile on
566 pre-ANSI compilers. Guile now requires ANSI C, so when you write new
567 functions, feel free to use ANSI declarations, and please provide
568 prototypes for everything. You don't need to use SCM_P in new code.
571 Jim Blandy, and others
574 Patches ===========================================================
576 This one makes cvs-1.10 consider the file $CVSDOTIGNORE instead of
577 .cvsignore when that environment variable is set.
580 diff -r -u cvs-1.10/src/cvs.h cvs-1.10.ignore-hack/src/cvs.h
581 --- cvs-1.10/src/cvs.h Mon Jul 27 04:54:11 1998
582 +++ cvs-1.10.ignore-hack/src/cvs.h Sun Jan 23 12:58:09 2000
585 extern int ign_name PROTO ((char *name));
586 void ign_add PROTO((char *ign, int hold));
587 -void ign_add_file PROTO((char *file, int hold));
588 +int ign_add_file PROTO((char *file, int hold));
589 void ign_setup PROTO((void));
590 void ign_dir_add PROTO((char *name));
591 int ignore_directory PROTO((char *name));
592 diff -r -u cvs-1.10/src/ignore.c cvs-1.10.ignore-hack/src/ignore.c
593 --- cvs-1.10/src/ignore.c Mon Sep 8 01:04:15 1997
594 +++ cvs-1.10.ignore-hack/src/ignore.c Sun Jan 23 12:57:50 2000
597 * Open a file and read lines, feeding each line to a line parser. Arrange
598 * for keeping a temporary list of wildcards at the end, if the "hold"
600 + * argument is set. Return true when the file exists and has been handled.
604 ign_add_file (file, hold)
610 if (! existence_error (errno))
611 - error (0, errno, "cannot open %s", file);
613 + error (0, errno, "cannot open %s", file);
616 while (getline (&line, &line_allocated, fp) >= 0)
617 ign_add (line, hold);
620 error (0, errno, "cannot close %s", file);
625 /* Parse a line of space-separated wildcards and add them to the list. */
630 + char *cvsdotignore;
632 /* Set SUBDIRS if we have subdirectory information in ENTRIES. */
638 - ign_add_file (CVSDOTIGNORE, 1);
639 + cvsdotignore = getenv("CVSDOTIGNORE");
640 + if (cvsdotignore == NULL || !ign_add_file (cvsdotignore, 1))
641 + ign_add_file (CVSDOTIGNORE, 1);
643 wrap_add_file (CVSDOTWRAPPER, 1);
645 while ((dp = readdir (dirp)) != NULL)
648 This one is for pcl-cvs-2.9.2, so that `i' adds to the local
652 --- pcl-cvs.el~ Mon Nov 1 12:33:46 1999
653 +++ pcl-cvs.el Tue Jan 25 21:46:27 2000
654 @@ -1177,7 +1177,10 @@
655 "Append the file in FILEINFO to the .cvsignore file.
656 Can only be used in the *cvs* buffer."
657 (save-window-excursion
658 - (set-buffer (find-file-noselect (expand-file-name ".cvsignore" dir)))
659 + (set-buffer (find-file-noselect
660 + (expand-file-name (or (getenv "CVSDOTIGNORE")
663 (goto-char (point-max))
664 (unless (zerop (current-column)) (insert "\n"))