[BuildTools] zlib and bzlib only with --enable-gnu-packages?

[Stefan Vigerske]

Hi,

according to
http://zlib.net/zlib_faq.html#faq23
and what is written in zlib.h (see below), zlib is not licensed under 
GNU, but a much more permissive license (can be used for any purpose).

Similar for bzlib (see below).

So I think of changing the checks for zlib and bzlib in coin.m4 so that 
it does not require --enable-gnu-packages to be given. Any objections?

Stefan


zlib.h:
/* zlib.h -- interface of the 'zlib' general purpose compression library
   version 1.2.3, July 18th, 2005

   Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler

   This software is provided 'as-is', without any express or implied
   warranty.  In no event will the authors be held liable for any damages
   arising from the use of this software.

   Permission is granted to anyone to use this software for any purpose,
   including commercial applications, and to alter it and redistribute it
   freely, subject to the following restrictions:

   1. The origin of this software must not be misrepresented; you must
      not claim that you wrote the original software. If you use this
      software in a product, an acknowledgment in the product
      documentation would be appreciated but is not required.
   2. Altered source versions must be plainly marked as such, and must
      not be misrepresented as being the original software.
   3. This notice may not be removed or altered from any source
      distribution.

   Jean-loup Gailly        Mark Adler
   jloup at gzip.org          madler at alumni.caltech.edu


   The data format used by the zlib library is described by RFCs 
(Request for
   Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
   (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip 
format).
*/



bzip2:

This program, "bzip2", the associated library "libbzip2", and all
documentation, are copyright (C) 1996-2010 Julian R Seward.  All
rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:

1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.

2. The origin of this software must not be misrepresented; you must
    not claim that you wrote the original software.  If you use this
    software in a product, an acknowledgment in the product
    documentation would be appreciated but is not required.

3. Altered source versions must be plainly marked as such, and must
    not be misrepresented as being the original software.

4. The name of the author may not be used to endorse or promote
    products derived from this software without specific prior written
    permission.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Julian Seward, jseward at bzip.org
bzip2/libbzip2 version 1.0.6 of 6 September 2010