Change license to LGPLv3+ or GPLv2.

4 files changed, 48 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index a88bfac..6315f07 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2016-12-02  Bruno Haible  <bruno@clisp.org>
 
+	Change license to LGPLv3+ or GPLv2.
+	* README (Copyright): Rewrite section.
+	* doc/libunistring.texi (Licenses): Change accordingly.
+	* autogen.sh: Pass option --lgpl=3orGPLv2 to gnulib-tool.
+	Reported by Nikos Mavrogiannopoulos.
+
+2016-12-02  Bruno Haible  <bruno@clisp.org>
+
 	Allow use of automake-1.15.
 	* autogen.sh: Update comments. Make sure to get new versions of files
 	brought in by automake.
diff --git a/README b/README
index e7b9dc1..633824f 100644
--- a/README
+++ b/README
@@ -45,8 +45,22 @@ As usual for GNU packages:
 Copyright
 ---------
 
-The libunistring library and its header files are under the GNU LGPL, see
-file COPYING.LIB.  This license is based on the GNU GPL, see file COPYING.
+The libunistring library and its header files are dual-licensed under
+"the GNU LGPLv3+ or the GNU GPLv2". This means, you can use it under either
+  - the terms of the GNU Lesser General Public License (LGPL) version 3 or
+    (at your option) any later version, or
+  - the terms of the GNU General Public License (GPL) version 2, or
+  - the same dual license "the GNU LGPLv3+ or the GNU GPLv2".
+
+You find the GNU LGPL version 3 in the file COPYING.LIB.  This license is
+based on the GNU GPL version 3, see file COPYING.
+
+You can find the GNU GPL version 2 at
+<https://www.gnu.org/licenses/old-licenses/gpl-2.0.html>.
+
+Note: This dual license makes it possible for the libunistring library
+to be used by packages under GPLv2 or GPLv2+ licenses, in particular. See
+the table in <https://www.gnu.org/licenses/gpl-faq.html#AllCompatibility>.
 
 The documentation is under another license; see in the documentation.
 
diff --git a/autogen.sh b/autogen.sh
index b7c925e..c738a86 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -424,7 +424,7 @@ if test $skip_gnulib = false; then
       relocatable-lib-lgpl
     '
     $GNULIB_TOOL --lib=libunistring --source-base=lib --m4-base=gnulib-m4 --tests-base=tests \
-      --with-tests --lgpl --makefile-name=Makefile.gnulib --libtool --local-dir=gnulib-local \
+      --with-tests --lgpl=3orGPLv2 --makefile-name=Makefile.gnulib --libtool --local-dir=gnulib-local \
       --import $GNULIB_MODULES
     # Change lib/unistr.h to be usable standalone.
     sed -e 's/if GNULIB_[A-Za-z0-9_]* || .*/if 1/g' \
diff --git a/doc/libunistring.texi b/doc/libunistring.texi
index 15baa3a..43a6ba5 100644
--- a/doc/libunistring.texi
+++ b/doc/libunistring.texi
@@ -86,7 +86,7 @@ This manual is for GNU libunistring.
 
 @ignore
 @c This was: @copying but it triggers a makeinfo 4.13 bug
-Copyright (C) 2001-2010 Free Software Foundation, Inc.
+Copyright (C) 2001-2016 Free Software Foundation, Inc.
 
 This manual is free documentation.  It is dually licensed under the
 GNU FDL and the GNU GPL.  This means that you can redistribute this
@@ -118,7 +118,7 @@ A copy of the license is included in @ref{GNU GPL}.
 @page
 @vskip 0pt plus 1filll
 @c @insertcopying
-Copyright (C) 2001-2010 Free Software Foundation, Inc.
+Copyright (C) 2001-2016 Free Software Foundation, Inc.
 
 This manual is free documentation.  It is dually licensed under the
 GNU FDL and the GNU GPL.  This means that you can redistribute this
@@ -937,9 +937,27 @@ particular file or directory.  Here is a summary:
 
 @itemize @bullet
 @item
-The @code{libunistring} library is covered by the
-GNU Lesser General Public License (LGPL).
-A copy of the license is included in @ref{GNU LGPL}.
+The @code{libunistring} library and its header files are dual-licensed under
+"the GNU LGPLv3+ or the GNU GPLv2". This means, you can use it under either
+@itemize
+@item @minus{}
+the terms of the GNU Lesser General Public License (LGPL) version 3 or
+(at your option) any later version, or
+@item @minus{}
+the terms of the GNU General Public License (GPL) version 2, or
+@item @minus{}
+the same dual license "the GNU LGPLv3+ or the GNU GPLv2".
+@end itemize
+You find the GNU LGPL version 3 in @ref{GNU LGPL}.  This license is
+based on the GNU GPL version 3, see @ref{GNU GPL}.
+@*
+You can find the GNU GPL version 2 at
+@url{https://www.gnu.org/licenses/old-licenses/gpl-2.0.html}.
+@*
+Note: This dual license makes it possible for the @code{libunistring} library
+to be used by packages under GPLv2 or GPLv2+ licenses, in particular. See
+the table in @url{https://www.gnu.org/licenses/gpl-faq.html#AllCompatibility}.
+
 
 @item
 This manual is free documentation.  It is dually licensed under the