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[bpt/emacs.git] / admin / notes / copyright

Copyright (C) 2007  Free Software Foundation, Inc.
See the end of the file for license conditions.


NOTES ON COPYRIGHTS AND LICENSES

Some terminology:

A "copyright notice" consists of one or a few lines of this format:
"Copyright (C) 2006, 2007 Free Software Foundation, Inc."

A "license notice" is a statement of permissions, and is usually much
longer, eg the text "GNU Emacs is free software...".


Summary for the impatient:

1. Don't add a file to Emacs written by someone other than yourself
without thinking about the legal aspect (make sure they have an
assignment, adjust the copyright statements in the file). NB the
ChangeLog entry should be in the name of the author of the code, not
the person who installs it.

2. With images, add the legal info to a README file in the directory
containing the image.

3. If you add a lot of text to a previously trivial file that had no
legal notices, consider if you should add a copyright statement.

4. Please don't just add an FSF copyright without checking that is the
right thing to do.


Every non-trivial file distributed through the Emacs CVS should be
self-explanatory in terms of copyright and license. This includes
files that are not distributed in Emacs releases (for example, the
admin/ directory), because the whole Emacs CVS is publicly
available.

The definition of triviality is a little vague, but a rule of thumb is
that any file with less than 15 lines of actual content is trivial. If
a file is auto-generated (eg ldefs-boot.el) from another one in the
CVS, then it does not really matter about adding a copyright statement
to the generated file.

Legal advice says that we could, if we wished, put a license notice
even in trivial files, because copyright law in general looks at the
overall work as a whole. It is not _necessary_ to do so, and rms
prefers that we do not. This means one needs to take care that trivial
files do not grow and become non-trivial without having a license
added. NB consequently, if you add a lot of text to a small file,
consider whether your changes have made the file worthy of a copyright
notice, and if so, please add one.

It can be helpful to put a reminder comment at the start of a trivial
file, eg: "add a license notice if this grows to > 10 lines of code".

The years in the copyright notice should be updated every year (see
file "years" in this directory). The PS versions of refcards etc
should display copyright notices (an exception to the rule about
"generated" files), but these can just display the latest year. The
full list of years should be kept in comments in the source file. If
these are distributed in CVS, check in a regenerated version when the
tex files are updated.

Copyright changes should be propagated to any associated repositories
(eg Gnus, MH-E), but I think in every case this happens automatically
(?).

All README (and other such text files) that are non-trivial should
contain copyright statements and GPL license notices, exactly as .el
files do (see e.g. README in the top-level directory). Before 2007,
we used a simple, short statement permitting copying and modification
provided legal notices were retained. In Feb 2007 we switched to the
standard GPL text, on legal advice. Some older text files in etc/
should, however, keep their current licenses (see below for list).

For image files, the copyright and license details should be recorded
in a README file in each directory with images. (Legal advice says
that we need not add notices to each image file individually, if they
allow for that.). It is recommended to use the word "convert" to
describe the automatic process of changing an image from one format to
another (http://lists.gnu.org/archive/html/emacs-devel/2007-02/msg00618.html).


When installing a file with an "unusual" license (after checking first
it is ok), put a copy of the copyright and license in the file (if
possible. It's ok if this makes the file incompatible with its
original format, if it can still be used by Emacs), or in a README
file in the relevant directory.

The vast majority of files are copyright FSF and distributed under the
GPL. A few files (mainly related to language and charset support) are
copyright AIST alone, or both AIST and FSF. (Contact Kenichi Handa
with questions about legal issues in such files.) In all these cases,
the copyright years in each file should be updated each year.

There are some exceptions to the points in the previous paragraph, and
these are listed below for reference, together with any files where
the copyright needs to be updated in "unusual" ways.

If you find any other such cases, please consult to check they are ok,
and note them in this file. This includes missing copyright notices,
and "odd" copyright holders. In most cases, individual authors should
not appear in copyright statements. Either the copyright has been
assigned (check copyright.list) to the FSF (in which case the original
author should be removed and the year(s) transferred to the FSF); or
else it is possible the file should not be in Emacs at all (please
report!).

Note that it seems painfully clear that one cannot rely on CVS logs,
or even ChangeLogs, for older changes. People often installed changes
from others, without recording the true authorship.

[For reference, most of these points were established via email with
rms, 2007/1, "Copyright years".]


lib-src/etags.c           # print_version
lib-src/rcs2log           # Copyright
lisp/calc/calc-help.el    # calc-full-help
lisp/startup.el           # fancy-splash-tail
mac/Emacs.app/Contents/Resources/English.lproj/InfoPlist.strings
mac/src/Emacs.r           # resource 'vers'
src/emacs.c
  - remember to change the latest copyright year in the --version output.
  [Post-release, will automate this like set-version does for version.]

<top-level>/install-sh
lispintro/install-sh
 - this file is copyright MIT, which is OK. Leave the copyright alone.

src/m/news-r6.h
  public domain, leave alone.

etc/edt-user.doc
  - update BOTH notices in this file

etc/emacs.csh
  - keep simple license for this simple file

etc/future-bug
 - doesn't need a humourless disclaimer, because Karl Fogel says we
 can consider it part of Emacs, and he has a blanker disclaimer for
 Emacs changes. (email to rgm "[Emacs-commit] emacs/etc future-bug",
 2007028)

etc/letter.pbm,letter.xpm
  - trivial, no notice needed.
<http://lists.gnu.org/archive/html/emacs-devel/2007-02/msg00324.html>

etc/FTP, ORDERS
  - trivial (at time of writing), no license needed

etc/GNU, INTERVIEW, LINUX-GNU, MOTIVATION, SERVICE, THE-GNU-PROJECT,
WHY-FREE
  rms: "These are statements of opinion or testimony. Their licenses
  should permit verbatim copying only. Please don't change the
  licenses that they have. They are distributed with Emacs but they
  are not part of Emacs."

etc/MAILINGLISTS
  rms: simple license is fine for this file

leim/CXTERM-DIC/4Corner.tit, ARRAY30.tit, CCDOSPY.tit, ECDICT.tit,
ETZY.tit, PY-b5.tit, Punct-b5.tit, Punct.tit, QJ-b5.tit, QJ.tit,
SW.tit, TONEPY.tit, ZOZY.tit
  - leave the copyrights alone.

leim/MISC-DIC/CTLau-b5.html, CTLau.html, cangjie-table.b5, cangjie-table.cns,
pinyin.map, ziranma.cin
  - leave the copyright alone.
Note that pinyin.map, ziranma.cin (and hence the generated
leim/quail/PY.el, ZIRANMA.el) are under GPLv1 or later.

leim/SKK-DIC/SKK-JISYO.L
ja-dic/ja-dic.el
  (the latter is auto-generated from the former). Leave the copyright alone.

lib-src/etags.c
  Copyright information is duplicated in etc/ETAGS.README. Update that
  file too.

  Until 2007 etags.c was described as being copyright FSF and Ken Arnold.
  After some investigation in Feb 2007, then to the best of our
  knowledge we believe that the original 1984 Emacs version was based
  on the version in BSD4.2. See for example this 1985 post from Ken Arnold:
  <http://groups.google.com/group/mod.sources/browse_thread/thread/ffe5c55845a640a9>
    I have received enough requests for the current source to ctags
    to post it. Here is the latest version (what will go out with
    4.3, modulo any bugs fixed during the beta period). It is the
    4.2 ctags with recognition of yacc and lex tags added.

  See also a 1984 version of ctags (no copyright) posted to net.sources:
  <http://groups.google.com/group/net.sources/msg/a21b6c21be12a98d>
  Version of etags.c in emacs-16.56 duplicates comment typos.

  Accordingly, in Feb 2007 we added a 1984 copyright for the
  University of California and a revised BSD license. The terms of
  this require that the full license details be available in binary
  distributions - hence the file etc/ETAGS.README. The fact that the
  --version output just says "Copyright <year> FSF" is apparently OK
  from a legal point of view.

lib-src/getopt1.c, getopt_int.h
  - these are from the GNU C library. Leave the copyrights alone.

lisp/play/tetris.el
  - no special rules about the copyright. We note here that we believe
  (2007/1) there is no problem with our use of the name "tetris" or
  the concept.
  rms: "My understanding is that game rules as such are not copyrightable."
  <http://lists.gnu.org/archive/html/emacs-devel/2007-01/msg00960.html>

lispref/doclicense.texi
man/doclicense.texi
  - leave the copyright alone in this imported file.

lisp/net/tramp.el
  - there are also copyrights in the body of the file. Update these too.


lwlib/
rms (2007/02/17): "lwlib is not assigned to the FSF; we don't consider
it part of Emacs. [...] Therefore non-FSF copyrights are ok in lwlib."

FSF copyrights should only appear in files which have undergone
non-trivial cumulative changes from the original versions in the Lucid
Widget Library. NB this means that if you make non-trivial changes to
a file with no FSF copyright, you should add one. Also, if changes are
reverted to the extent that a file becomes basically the same as the
original version, the FSF copyright should be removed.

In my (rgm) opinion, as of Feb 2007, all the non-trivial files differ
significantly from the original versions, with the exception of
lwlib-Xm.h. Most of the changes that were made to this file have
subsequently been reverted. Therefore I removed the FSF copyright from
this file (which is arguably too trivial to merit a notice anyway). I
added FSF copyright to the following files which did not have them
already: Makefile.in, lwlib-Xaw.c, lwlib-int.h (borderline),
lwlib-utils.c (borderline), lwlib.c, lwlib.h.

Copyright years before the advent of public CVS in 2001 were those
when I judged (from the CVS logs) that non-trivial amounts of change
had taken place. I also adjusted the existing FSF years in xlwmenu.c,
xlwmenu.h, and xlwmenuP.h on the same basis.

Note that until Feb 2007, the following files in lwlib were lacking
notices: lwlib-int.h, lwlib.h, lwlib-Xaw.h, lwlib-Xlw.h, lwlib-utils.h

The following files did not list a Lucid copyright: xlwmenu.h,
xlwmenuP.h.

To the best of our knowledge, all the code files in lwlib were
originally part of the Lucid Widget Library, even if they did not say
so explicitly. For example, they were all present in Lucid Emacs 19.1
in 1992. The exceptions are the two Xaw files, which did not appear
till Lucid Emacs 19.9 in 1994. The file lwlib-Xaw.h is too trivial to
merit a copyright notice, but would presumably have the same one as
lwlib-Xaw.c. We have been unable to find a true standalone version of
LWL, if there was such a thing, to check definitively.

To clarify the situation, in Feb 2007 we added Lucid copyrights and
GPL notices to those files lacking either that were non-trivial,
namely: lwlib-int.h, lwlib.h, xlwmenu.h, xlwmenuP.h. This represents
our best understanding of the legal status of these files. We also
clarified the notices in Makefile.in, which was originally the
Makefile auto-generated from Lucid's Imakefile.

As of Feb 2007, the following files are considered too trivial for
notices: lwlib-Xaw.h, lwlib-Xlw.h, lwlib-utils.h.


msdos/is_exec.c, sigaction.c
  - these files are copyright DJ Delorie. Leave the copyrights alone.
  Leave the Eli Zaretskii copyright in is_exec.c alone. See the
  msdos/README file for the legal history of these files.


oldXMenu/
  Keep the "copyright.h" method used by X11, rather than moving the
  licenses into the files. Note that the original X10.h did not use
  copyright.h, but had an explicit notice, which we retain.

If you make non-trivial changes to a file which does not have an FSF
notice, add one and a GPL notice (as per Activate.c). If changes to a
file are reverted such that it becomes essentially the same as the
original X11 version, remove the FSF notice and GPL.

Only the files which differ significantly from the original X11
versions should have FSF copyright and GPL notices. At time of writing
(Feb 2007), this is: Activate.c, Create.c, Internal.c. I (rgm)
established this by diff'ing the current files against those in X11R1,
and when I found significant differences looking in the ChangeLog for
the years they originated (the CVS logs are truncated before 1999). I
therefore removed the FSF notices (added in 200x) from the other
files. There are some borderline cases IMO: AddSel.c, InsSel.c,
XMakeAssoc.c, XMenu.h. For these I erred on the side of NOT adding FSF
notices.

With regards to whether the files we have changed should have GPL
added or not, rms says (2007-02-25, "oldXmenu issues"):

    It does not make much difference, because oldXmenu is obsolete
    except for use in Emacs (and it is not normally used in Emacs any
    more either).

    So, to make things simple, please put our changes under the GPL.

insque.c had no copyright notice until 2005. The version of insque.c
added to Emacs 1992-01-27 is essentially the same as insremque.c added
to glic three days later by Roland McGrath, with an FSF copyright and
GPL, but no ChangeLog entry:
<http://sources.redhat.com/cgi-bin/cvsweb.cgi/~checkout~/libc/misc/insremque.c?\
rev=1.1&cvsroot=glibc>
To the best of his recollection, McGrath (who has a copyright
assignment) was the author of this file (email from roland at frob.com
to rms, 2007-02-23, "Where did insque.c come from?"). The FSF
copyright and GPL in this file are therefore correct as far as we
understand it.

Imakefile had no legal info in Feb 2007, but was obviously based on
the X11 version (which also had no explicit legal info). As it was
unused, I removed it. It would have the same MIT copyright as
Makefile.in does now.


src/gmalloc.c
  - contains numerous copyrights from the GNU C library. Leave them alone.

src/acldef.h, chpdef.h, ndir.h
  - see comments below. These files are OK to be released with Emacs
  22, but we may want to revisit them afterwards.

[src/unexhp9k800.c - removed 2007/1/27]
[src/m/sr2k.h - removed 2007/1/27]
  - First file removed due to legal uncertainties; second file removed
  due to dependency on first. Note that src/m/hp800.h is still needed on
  hp800 arch.
  NB we would like to re-add this file if we can. Please let us know
  if you can clarify its legal status.


** Some notes on resolved issues, for historical information only

lisp/term/README
  - had no copyright notice till Feb 2007. ChangeLog.3 suggests it was
  written by Eric Raymond. When asked by rms on 14 Feb 2007 he said:

    I don't remember writing it, but it reads like my prose and I believe
    I wrote the feature(s) it's describing.  So I would have been the
    likeliest person to write it.

    Odds are that I did, but I'm not certain.

  Accordingly, FSF copyright was added.


** Issues that are "fixed" for the release of Emacs 22, but we may
   wish to revisit later in more detail


admin/check-doc-strings
  File says it's in the public domain, but that might not make it so.


etc/e/eterm-color.ti
src/acldef.h, chpdef.h, ndir.h
  On legal advice from Matt Norwood, the following comment was added
  to these files in Feb 2007:

    The code here is forced by the interface, and is not subject to
    copyright, constituting the only possible expression of the
    algorithm in this format.

  With the addition of this notice, these files are OK for the
  upcoming Emacs-22 release. Post-release, we can revisit this issue
  and possibly add a list of all authors who have changed these files.
  (details in email from Matt Norwood to rms, 2007/02/03).


src/m/mips4.h, news-risc.h, pmax.h
src/s/aix3-2.h, bsd386.h, hpux8.h, hpux9.h, irix4-0.h, irix5-0.h,
isc2-2.h, netbsd.h, osf1.h, sol2-3.h, sunos4-0.h, usg5-4-2.h
  - all these (not obviously trivial) files were missing copyrights
  till Feb 2007, when FSF copyright was added. Matt Norwood advised:

    For now, I think the best policy is to assume that we do have
    assignments from the authors (I recall many of these header files
    as having been originally written by rms), and to attach an FSF
    copyright with GPL notice. We can amend this if and when we
    complete the code audit. Any additions to these files by
    non-assigned authors are arguably "de minimis" contributions to
    Emacs: small changes or suggestions to a work that are subsumed in
    the main authors' copyright in the entire work.

Here is my (rgm) take on the details of the above files:

mips4.h
  might be trivial? started trivial, been added to in tiny changes by
  those with FSF assignment, often result of email suggestions by others.

news-risc.h
  started trivial. Grown by tiny additions, plus chunk
  from mips.h, which was and is Copyright FSF

pmax.h
  started trivial. grown in tiny changes, except for maybe Jim Wilson's
  comment.

? irix4-0.h
  I would say started non-trivial (1992, rms). only tiny changes since
  installed.

? irix5-0.h
  I would say started non-trivial (1993, jimb, heavily based
  on irix4-0.h). A few borderline non-tiny changes since.

? isc2-2.h
 started trivial. 2 non-tiny change, in 1993. looks to
 be made up of several small tweaks from various sources. maybe
 non-tiny total changes from Karl Berry (no emacs assignment).

osf1.h
  started trivial. grown in tiny changes (one borderline tiny change
  by fx in 2000, but most code was later removed). non-tiny addition
  in 2002 from m/alpha.h, but that was and is copyright FSF.

usg5-4-2.h
 started non-trivial, but was heavily based on usg5-4.h, which was and is
 copyright FSF. only tiny changes since installed.

sol2-3.h
 started trivial. only non-tiny change (1994) incorporated code from
 usg5-4.h, which was and is copyright FSF.

aix3-2.h, bsd386.h, hpux8.h, hpux9.h, netbsd.h, sunos4-0.h
  started trivial, grown in tiny changes.

netbsd.h:
Roland McGrath said to rms (2007/02/17): "I don't really remember
anything about it. If I put it in without other comment, then probably
I wrote it myself."


Someone might want to tweak the copyright years (for dates before
2001) that I used in all these files.

Note: erring on the side of caution, I also added notices to some
files I thought might be considered non-trivial (if one includes
comment) in s/:
  aix4-1.h hiuxmpp.h hiuxwe2.h hpux10.h irix6-0.h irix6-5.h isc3-0.h
  ptx4.h sol2.h sunos4-0.h

(everything with > 30 non-blank lines, which at least is _some_ kind of
system)


*** These are copyright issues that need not be fixed until after
    Emacs 22 is released (though if they can be fixed before, that is
    obviously good):

Maybe some relevant comments here?
<http://groups.google.com/group/linux.debian.legal/browse_thread/thread/123547ea95437a1f>


Is it OK to just `cvs remove' a file for legal reasons, or is
something more drastic needed? A removed file is still available from
CVS, if suitable options are applied. (This CVS issue obviously does
not affect a release).
  rms: will ask lawyer


Make sure that all files with non-standard copyrights or licenses are
noted in this file.


etc/BABYL
  File says it was written in 1983 by Eugene Ciccarelli, who has no
  assignment. RMS: "The lawyer said we can keep BABYL."


REMOVED etc/gnu.xpm, nt/icons/emacs21.ico, nt/icons/sink.ico
  - Restore if find legal info. emacs21.ico is not due to Davenport.
  Voelker could not immediately recall anything, but will check and
  let us know if he finds anything.


etc/images
  Image files from GTK, Gnome are under GPLv2 (no "or later"?). RMS will
  contact image authors in regards to future switch to v3.


REMOVED src/unexhp9k800.c
  - we would like to re-add this file if possible. Please let us know
  if you can clarify its legal status.
  http://lists.gnu.org/archive/html/emacs-devel/2007-02/msg00138.html


*** These are copyright issues still to be addressed:

NB apart from switching the TUTORIALs to GPL, I think there is nothing
here that anyone can work on without further input from rms.


etc/gnus-logo.eps, gnus-booklet.ps, gnus-refcard.ps
 just to be safe, papers are on the way for the "Gnus logo", even
 though it is very similar to the already-assigned "Emacs logo".


etc/ms-kermit - no copyright, but ms-7bkermit has one


etc/TUTORIAL* (translations)
  switch to GPL (see english TUTORIAL)
  rms: "We can leave the TUTORIAL translations alone until their
  maintainers update them."
  Can adapt short license text from end of GPL translations at:
  http://www.gnu.org/licenses/translations.html
  Only a few sentences around the license notice need changing from
  previous version.
Done: TUTORIAL.eo


lwlib/*
  should it be under GPLv1 or later, or v2 or later, or some mixture?


\f
This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Emacs 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.