Switching the Cygwin DLL to LGPLv3+, dropping commercial buyout optioncygwin-2_5_2-release

Bump GPLv2+ to GPLv3+ for some files, clarify BSD 2-clause.

Everything else stays under GPLv3+.

New Linking Exception exempts resulting executables from LGPLv3 section 4.

Add CONTRIBUTORS file to keep track of licensing.

Remove 'Copyright Red Hat Inc' comments.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

9 files changed, 23 insertions, 46 deletions

diff --git a/winsup/doc/Makefile.in b/winsup/doc/Makefile.in
index cfe206d..b28094b 100644
--- a/winsup/doc/Makefile.in
+++ b/winsup/doc/Makefile.in
@@ -1,6 +1,4 @@
 # -*- Makefile -*- for winsup/doc
-# Copyright (c) 1998-2000, 2001, 2002, 2004, 2005, 2006, 2008, 2009, 2010,
-# 2013, 2014 Red Hat, Inc.
 #
 # This file is part of Cygwin.
 #
diff --git a/winsup/doc/bodysnatcher.pl b/winsup/doc/bodysnatcher.pl
index 1db30aa..74d893c 100755
--- a/winsup/doc/bodysnatcher.pl
+++ b/winsup/doc/bodysnatcher.pl
@@ -1,5 +1,4 @@
 #!/usr/bin/perl -w
-# Copyright © 2013 by Red Hat, Inc.
 #
 # This file is part of Cygwin.
 # 
diff --git a/winsup/doc/configure.ac b/winsup/doc/configure.ac
index 6c80041..8364dc7 100644
--- a/winsup/doc/configure.ac
+++ b/winsup/doc/configure.ac
@@ -1,5 +1,4 @@
 dnl Autoconf configure script for winsup/doc
-dnl Copyright 1997, 1998, 1999, 2000, 2001, 2006, 2012, 2013, 2014 Red Hat, Inc.
 dnl
 dnl This file is part of Cygwin.
 dnl 
diff --git a/winsup/doc/faq-programming.xml b/winsup/doc/faq-programming.xml
index d120973..3aa773a 100644
--- a/winsup/doc/faq-programming.xml
+++ b/winsup/doc/faq-programming.xml
@@ -496,9 +496,8 @@ self-contained executable.
 </para>
 <para>If this is an issue because you intend to distribute your Cygwin
 application, then you had better read and understand
-<ulink url="https://cygwin.com/licensing.html"/>, which explains the licensing
-options.  Unless you purchase a special commercial license from Red
-Hat, then your Cygwin application must be Open Source.
+<ulink url="https://cygwin.com/licensing.html"/>, which explains the
+licensing options.
 </para>
 </answer></qandaentry>
 
@@ -548,15 +547,6 @@ have our own Win32 headers which are pretty complete.
 <question><para>How do I use <literal>cygwin1.dll</literal> with Visual Studio or Mingw-w64?</para></question>
 <answer>
 
-<para>Before you begin, note that Cygwin is licensed under the GNU GPL (as
-indeed are many other Cygwin-based libraries).  That means that if your
-code links against the Cygwin dll (and if your program is calling
-functions from Cygwin, it must, as a matter of fact, be linked against
-it), you must apply the GPL to your source as well.  Of course, this
-only matters if you plan to distribute your program in binary form.  For
-more information, see <ulink url="http://gnu.org/licenses/gpl-faq.html"/>.  If
-that is not a problem, read on.
-</para>
 <para>If you want to load the DLL dynamically, read
 <literal>winsup/cygwin/how-cygtls-works.txt</literal> and the sample code in
 <literal>winsup/testsuite/cygload</literal> to understand how this works.
diff --git a/winsup/doc/faq-using.xml b/winsup/doc/faq-using.xml
index 76f9058..412dfbb 100644
--- a/winsup/doc/faq-using.xml
+++ b/winsup/doc/faq-using.xml
@@ -572,13 +572,15 @@ contributing it for others to use)
 Can I bundle Cygwin with my product for free?
 </para></question>
 <answer><para>
-Only if you comply with Cygwin's <ulink
-url="https://cygwin.com/licensing.html">license</ulink> very carefully.  If you
-choose to distribute cygwin1.dll, you must be willing to distribute the
-exact source code used to build that copy of cygwin1.dll as per the
-terms of the GPL.  If you ship applications that link with cygwin1.dll,
-you must either provide those applications' source code under a
-GPL-compatible license, *or* purchase a cygwin license from Red Hat.
+Starting with Cygwin version 2.5.2, which is LGPL licensed, yes, albeit
+it's not recommended for interoperability reasons.</para>
+
+<para>Cygwin versions prior to 2.5.2 were GPL licensed.
+If you choose to distribute an older cygwin1.dll, you must be willing to
+distribute the exact source code used to build that copy of cygwin1.dll
+as per the terms of the GPL.  If you ship applications that link with
+older cygwin1.dll, you must provide those applications' source code
+under a GPL-compatible license.
 </para></answer></qandaentry>
 
 <qandaentry id="faq.using.older-cygwin-conflict">
diff --git a/winsup/doc/faq-what.xml b/winsup/doc/faq-what.xml
index 056cf91..393516a 100644
--- a/winsup/doc/faq-what.xml
+++ b/winsup/doc/faq-what.xml
@@ -74,17 +74,10 @@ but you should be sure to read the copyright section of the FAQ for more
 information on how the GNU General Public License may affect your use of
 these tools.
 </para>
-<para>In particular, if you intend to port a proprietary (non-GPL'd)
-application using Cygwin, you will need the proprietary-use license 
-for the Cygwin library.  This is available for purchase from Red Hat;
-please visit <ulink url="https://cygwin.com/licensing.html"/> for more
-information.  All other questions should be sent to the public project
-mailing list cygwin@cygwin.com.
-</para>
 <para>Note that when we say "free" we mean freedom, not price.  The goal of
 such freedom is that the people who use a given piece of software
 should be able to change it to fit their needs, learn from it, share
-it with their friends, etc.  The Cygwin license allows you those
+it with their friends, etc.  The GPL or LGPL licenses allows you those
 freedoms, so it is free software.
 </para>
 </answer></qandaentry>
diff --git a/winsup/doc/intro.xml b/winsup/doc/intro.xml
index 96cfd21..5e96d8b 100644
--- a/winsup/doc/intro.xml
+++ b/winsup/doc/intro.xml
@@ -36,8 +36,9 @@
       including FAQ, User's Guide, and API Reference. The
       <emphasis>Cygwin</emphasis> website should be considered the authoritative
       source of information. The source code, released under the <emphasis>GNU
-      General Public License, Version 3 (GPLv3+)</emphasis>, is also available
-      from the website or one of the mirrors.</para>
+      General Public License, Version 3 (GPLv3+)</emphasis> and
+      <emphasis>Lesser GNU General Public License, Version 3 (LGPLv3+)</emphasis>,
+      is also available from the website or one of the mirrors.</para>
     </refsect1>
     <refsect1>
       <title>COMPATIBILITY</title>
@@ -142,7 +143,8 @@
       url="http://cygwin.com"/>. The website has extensive documentation,
       including FAQ, User's Guide, and API Reference. It should be considered
       the authoritative source of information. The source code, released under
-      the <emphasis>GNU General Public License, Version 3 (GPLv3+)</emphasis>,
+      the <emphasis>GNU General Public License, Version 3 (GPLv3+)</emphasis> and
+      <emphasis>Lesser GNU General Public License, Version 3 (LGPLv3+)</emphasis>,
       is also available from the website or one of the mirrors.</para>
     </refsect1>
     <refsect1>
diff --git a/winsup/doc/legal.xml b/winsup/doc/legal.xml
index 06b5577..fba3fdd 100644
--- a/winsup/doc/legal.xml
+++ b/winsup/doc/legal.xml
@@ -4,7 +4,7 @@
 
 <legalnotice id="legal">
 
-<para>Copyright &copy; 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Red Hat, Inc.</para>
+<para>Copyright &copy; Cygwin authors</para>
 
 <!--
 
diff --git a/winsup/doc/overview.xml b/winsup/doc/overview.xml
index 1086c01..6fb759f 100644
--- a/winsup/doc/overview.xml
+++ b/winsup/doc/overview.xml
@@ -45,17 +45,11 @@ parts are covered by the standard
 <ulink url="http://www.x.org/Downloads_terms.html">X11 license</ulink>, 
 some of it is public domain, some of it was written by Red Hat and placed under
 the <ulink url="http://www.gnu.org/licenses/gpl.html">GNU General Public 
-License</ulink> (GPL). None of it is shareware. You don't have to pay anyone to
-use it but you should be sure to read the copyright section of the FAQ for more
-information on how the GNU GPL may affect your use of these
-tools. If you intend to port a proprietary application using the Cygwin
-library, you may want the Cygwin proprietary-use license.
-For more information about the proprietary-use license, please go to
-<ulink url="http://www.redhat.com/services/custom/cygwin/"/>. 
-Customers of the native Win32 GNUPro should feel free to submit bug
-reports and ask questions through Red Hat channels.  All other
-questions should be sent to the project mailing list
-<email>cygwin@cygwin.com</email>.</para>
+License</ulink> (GPL) or <ulink url="http://www.gnu.org/licenses/lgpl.html">
+GNU Lesser General Public License</ulink> (LGPL). None of it is shareware.
+You don't have to pay anyone to use it but you should be sure to read the
+copyright section of the FAQ for more information on how the GNU GPL may
+affect your use of these tools.</para>
 
 </sect1>