COPYING
=======

Describes the terms under which Nuttx is distributed. A copy of the BSD-
style licensing is included in this file. In my words -- I believe that you
should free to use NuttX in any environment, private, private, commercial,
open, closed, etc. provided only that you respect the modest copyright
notices as described in license (below), respect Trademarks, and include a
copy of the BSD license.  Please feel free to contact me if you have any 
icensing concerns.

Tool Licenses
-------------

Tools under the nuttx/tools directory are not intended for binary
distribution.  You may find other licensing on individual tools in that
directory.  If you intend to redistribute these tools in binary form, please
respect the individual license of each tool as identified in the file header
of the tool source files.

Copyright Date Notation
-----------------------

Copyright information is provided in the header of each file.  This
copyright information includes the name of the copyright holder and the
year(s) in which copyrighted additions to the file were made to the file.
A comma (',') is used to separate years in the list of years.  A hyphen ('-')
is used as a more compact notation when additions were made over several
consecutive years.  So for example, "2007, 2011" would mean that copyrighted
additions were made during the years of 2007 and 2011 whereas "2007-2011"
would indicate copyrighted additions in the years 2007, 2008, 2009, 2010,
and 2011.

Copyright Line Continuation
---------------------------

Copy information which exceeds the usable line lengh may be broken and
continued on the following line, such as:

   Copyright (C) 2007-2010, 2012, 2014-2015, 2017 Gregory Nutt.  All
     rights reserved.

NuttX
=====

License for NuttX in general (authorship and copyright dates on individual
files will vary):

/****************************************************************************
 * directory path/filename
 *
 *   Copyright (C) 2007-2019 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * 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. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "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
 * COPYRIGHT OWNER OR CONTRIBUTORS 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.
 *
 ****************************************************************************/

FAT Long File Names
===================

  NOTE:  If CONFIG_FAT_LFN is defined in your NuttX configuration file, then
  there may be some legal, patent issues. The following was extracted from
  the entry "File Allocation Table from Wikipedia, the free encyclopedia:

    "On December 3, 2003 Microsoft announced it would be offering licenses
     for use of its FAT specification and 'associated intellectual property',
     at the cost of a US$0.25 royalty per unit sold, with a $250,000 maximum
     royalty per license agreement.

     o "U.S. Patent 5,745,902 (http://www.google.com/patents?vid=5745902) -
        Method and system for accessing a file using file names having
        different file name formats. ...
     o "U.S. Patent 5,579,517 (http://www.google.com/patents?vid=5579517) -
        Common name space for long and short filenames. ...
     o "U.S. Patent 5,758,352 (http://www.google.com/patents?vid=5758352) -
        Common name space for long and short filenames. ...
     o "U.S. Patent 6,286,013 (http://www.google.com/patents?vid=6286013) -
        Method and system for providing a common name space for long and
        short file names in an operating system. ...

    "Many technical commentators have concluded that these patents only cover
     FAT implementations that include support for long filenames, and that
     removable solid state media and consumer devices only using short names
     would be unaffected. ..."

  This Wikipedia entry has been updated with recent legal decisions in favor
  of Microsoft. Refer to:

    https://en.wikipedia.org/wiki/File_Allocation_Table#Patents

  So you have been forewarned:  Use the long filename at your own risk!

uIP
===

Many lower-level networking components of NuttX derive from uIP which
has a similar BSD style license:

   Copyright (c) 2001-2003, Adam Dunkels.
   All rights reserved.

Rhombus Math Library
====================

The math library used in NuttX derives from the Rhombus OS by Nick Johnson
(with many, many addtions).  The Rhombus OS is/was distributed under the ISC
license.  The ISC licsense is a permissive license that allows people do
anything with your code with proper attribution and without warranty.  The
ISC license is functionally equivalent to the BSD 2-Clause and MIT licenses,
removing some language that is no longer necessary.

IGMP
===

IGMP support, if enabled, adds additional logic by Steve Reynolds:

  Copyright (c) 2002 CITEL Technologies Ltd.
  All rights reserved.

The HID Parser in drivers/usbhost
=================================

  Adapted from the LUFA Library (MIT license):

    Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)
    dean [at] fourwalledcubicle [dot] com, www.lufa-lib.org

  Permission to use, copy, modify, distribute, and sell this
  software and its documentation for any purpose is hereby granted
  without fee, provided that the above copyright notice appear in
  all copies and that both that the copyright notice and this
  permission notice and warranty disclaimer appear in supporting
  documentation, and that the name of the author not be used in
  advertising or publicity pertaining to distribution of the
  software without specific, written prior permission.

  The author disclaim all warranties with regard to this
  software, including all implied warranties of merchantability
  and fitness.  In no event shall the author be liable for any
  special, indirect or consequential damages or any damages
  whatsoever resulting from loss of use, data or profits, whether
  in an action of contract, negligence or other tortious action,
  arising out of or in connection with the use or performance of
  this software.

Certain functions in the NuttX C-library derive from other BSD-compatible
sources:

fs/nfs
======

   NFS:

     Copyright (c) 1989, 1991, 1993, 1995 The Regents of the University of
       California.  All rights reserved.

   and RPC also has:

     Copyright (c) 2004 The Regents of the University of Michigan.
     Copyright (c) 2004 Weston Andros Adamson <muzzle@umich.edu>.
     Copyright (c) 2004 Marius Aamodt Eriksen <marius@umich.edu>.

   The University of Michigan uses a modified BSD license equivalent to
   the NuttX license.  The University of California code uses the original
   BSD license and requires that I state the following:

  "This product includes software developed by the University of
   California, Berkeley and its contributors."

fs/spiffs
=========

  The MIT License (MIT)

  Copyright (c) 2013-2017 Peter Andersson (pelleplutt1976<at>gmail.com)

  Permission is hereby granted, free of charge, to any person obtaining a copy of
  this software and associated documentation files (the "Software"), to deal in
  the Software without restriction, including without limitation the rights to
  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
  the Software, and to permit persons to whom the Software is furnished to do so,
  subject to the following conditions:

  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
  COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

strtod()
========

  Copyright (C) 2002 Michael Ringgaard. All rights reserved.
  Copyright (C) 2006-2007 H. Peter Anvin.

dtoa()
======

  If you enable floating point conversions with CONFIG_LIBC_FLOATINGPOINT,
  then some files with an unmodified BSD license will be included.  That
  license is similar to the above (modified) BSD license, but has an
  additional requirement that I state the following:

  "This product includes software developed by the University of
   California, Berkeley and its contributors."

libc/string/lib_vikmemcpy.c
===========================

  If you enable CONFIG_MEMCPY_VIK, then you will build with the optimized
  version of memcpy from Daniel Vik.  Licensing information for that version
  of memcpy() follows:

  Copyright (C) 1999-2010 Daniel Vik

  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
     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.

libs/libc/math
==============

  If you enable CONFIG_LIB, you will build the math library at libc/math.
  This library was taken from the math library developed for the Rhombus
  OS by Nick Johnson (https://github.com/nickbjohnson4224/rhombus).  This
  port was contributed by Darcy Gong.  The Rhombus math library has this
  compatible MIT license:

    Copyright (C) 2009-2011 Nick Johnson <nickbjohnson4224 at gmail.com>

  Permission to use, copy, modify, and distribute this software for any
  purpose with or without fee is hereby granted, provided that the above
  copyright notice and this permission notice appear in all copies.

  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

drivers/video/ov2640
====================

  WARNING:  Some of the information in the data tables in this file came
  from other projects with conflicting licenses:  Linux and ArduCAM.  Those
  both have GPL licenses.  I am not sure if it is proper or not to lift the
  content of those tables and still retain this BSD license.  I am guessing
  so, but I am not a copyright attorney so you should use this driver in
  products at your own risk.