LICENSE.rst

   1
   2
   3 ==========================
   4 GNU GENERAL PUBLIC LICENSE
   5 ==========================
   6
   7 **Version 2, June 1991**
   8
   9     Copyright (C) 1989, 1991 Free Software Foundation, Inc.
  10     51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  11
  12     Everyone is permitted to copy and distribute verbatim copies
  13     of this license document, but changing it is not allowed.
  14
  15
  16 Preamble
  17 ========
  18
  19 The licenses for most software are designed to take away your freedom
  20 to share and  change it. By contrast, the GNU  General Public License
  21 is  intended to  guarantee  your  freedom to  share  and change  free
  22 software--to make sure  the software is free for all  its users. This
  23 General  Public  License  applies  to   most  of  the  Free  Software
  24 Foundation's software and  to any other program  whose authors commit
  25 to using it. (Some other Free Software Foundation software is covered
  26 by the GNU  Lesser General Public License instead.) You  can apply it
  27 to your programs, too.
  28
  29 When we  speak of  free software,  we are  referring to  freedom, not
  30 price. Our General Public Licenses are designed to make sure that you
  31 have the  freedom to distribute  copies of free software  (and charge
  32 for this  service if you wish),  that you receive source  code or can
  33 get it if you want it, that you can change the software or use pieces
  34 of  it in  new free  programs; and  that you  know you  can do  these
  35 things.
  36
  37 To  protect your  rights, we  need to  make restrictions  that forbid
  38 anyone  to deny  you these  rights  or to  ask you  to surrender  the
  39 rights.  These restrictions translate to certain responsibilities for
  40 you if you distribute copies of the software, or if you modify it.
  41
  42 For  example, if  you distribute  copies of  such a  program, whether
  43 gratis or for a fee, you must give the recipients all the rights that
  44 you have. You must  make sure that they, too, receive  or can get the
  45 source code.  And you must show  them these terms so  they know their
  46 rights.
  47
  48 We protect  your rights with  two steps: (1) copyright  the software,
  49 and (2)  offer you this license  which gives you legal  permission to
  50 copy, distribute and/or modify the software.
  51
  52 Also, for each author's protection and  ours, we want to make certain
  53 that everyone  understands that  there is no  warranty for  this free
  54 software. If the software is modified  by someone else and passed on,
  55 we  want its  recipients  to know  that  what they  have  is not  the
  56 original, so that any problems  introduced by others will not reflect
  57 on the original authors' reputations.
  58
  59 Finally,  any  free  program  is threatened  constantly  by  software
  60 patents. We  wish to avoid the  danger that redistributors of  a free
  61 program will  individually obtain  patent licenses, in  effect making
  62 the program proprietary. To prevent this,  we have made it clear that
  63 any patent must  be licensed for everyone's free use  or not licensed
  64 at all.
  65
  66 The  precise  terms  and  conditions for  copying,  distribution  and
  67 modification follow.
  68
  69
  70 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
  71 ===============================================================
  72
  73 0. This License applies to any program or other work which contains a
  74    notice placed by the copyright holder saying it may be distributed
  75    under the  terms of  this General  Public License.  The "Program",
  76    below, refers  to any such program  or work, and a  "work based on
  77    the Program" means either the Program or any derivative work under
  78    copyright law: that is to say,  a work containing the Program or a
  79    portion  of  it,  either  verbatim or  with  modifications  and/or
  80    translated  into another  language.  (Hereinafter, translation  is
  81    included  without limitation  in  the  term "modification".)  Each
  82    licensee is addressed as "you".
  83
  84    Activities other  than copying, distribution and  modification are
  85    not covered by  this License; they are outside its  scope. The act
  86    of running the Program is not  restricted, and the output from the
  87    Program is covered only if its contents constitute a work based on
  88    the  Program  (independent of  having  been  made by  running  the
  89    Program). Whether that is true depends on what the Program does.
  90
  91 1. You  may copy  and  distribute verbatim  copies  of the  Program's
  92    source code  as you receive it,  in any medium, provided  that you
  93    conspicuously   and  appropriately   publish  on   each  copy   an
  94    appropriate  copyright notice  and  disclaimer  of warranty;  keep
  95    intact  all the  notices that  refer to  this License  and to  the
  96    absence  of any  warranty; and  give any  other recipients  of the
  97    Program a copy of this License along with the Program.
  98
  99    You may charge a fee for  the physical act of transferring a copy,
 100    and you may  at your option offer warranty  protection in exchange
 101    for a fee.
 102
 103 2. You may modify  your copy or copies of the  Program or any portion
 104    of it,  thus forming  a work  based on the  Program, and  copy and
 105    distribute such modifications or work under the terms of Section 1
 106    above, provided that you also meet all of these conditions:
 107
 108    a) You must  cause the modified  files to carry  prominent notices
 109       stating that you changed the files and the date of any change.
 110
 111    b) You must cause any work that you distribute or publish, that in
 112       whole or in part contains or is derived from the Program or any
 113       part thereof,  to be licensed  as a whole  at no charge  to all
 114       third parties under the terms of this License.
 115
 116    c) If the  modified program normally reads  commands interactively
 117       when  run, you  must cause  it, when  started running  for such
 118       interactive use in  the most ordinary way, to  print or display
 119       an announcement including an appropriate copyright notice and a
 120       notice  that there  is no  warranty (or  else, saying  that you
 121       provide a warranty) and that users may redistribute the program
 122       under these conditions, and telling the user how to view a copy
 123       of  this   License.  (Exception:  if  the   Program  itself  is
 124       interactive but  does not normally print  such an announcement,
 125       your work  based on  the Program  is not  required to  print an
 126       announcement.)
 127
 128    These  requirements apply  to the  modified  work as  a whole.  If
 129    identifiable  sections  of that  work  are  not derived  from  the
 130    Program, and can be reasonably considered independent and separate
 131    works  in themselves,  then this  License, and  its terms,  do not
 132    apply  to those  sections  when you  distribute  them as  separate
 133    works. But  when you  distribute the  same sections  as part  of a
 134    whole which  is a work based  on the Program, the  distribution of
 135    the whole must be on the  terms of this License, whose permissions
 136    for other licensees  extend to the entire whole, and  thus to each
 137    and every part regardless of who wrote it.
 138
 139    Thus, it  is not  the intent  of this section  to claim  rights or
 140    contest your rights  to work written entirely by  you; rather, the
 141    intent is  to exercise  the right to  control the  distribution of
 142    derivative or collective works based on the Program.
 143
 144    In addition,  mere aggregation  of another work  not based  on the
 145    Program with the Program (or with  a work based on the Program) on
 146    a volume  of a storage or  distribution medium does not  bring the
 147    other work under the scope of this License.
 148
 149 3. You may  copy and distribute the  Program (or a work  based on it,
 150    under Section 2) in object code or executable form under the terms
 151    of Sections  1 and 2  above provided that you  also do one  of the
 152    following:
 153
 154    a) Accompany it  with the complete  corresponding machine-readable
 155       source  code, which  must  be distributed  under  the terms  of
 156       Sections  1  and 2  above  on  a  medium customarily  used  for
 157       software interchange; or,
 158
 159    b) Accompany it  with a  written offer, valid  for at  least three
 160       years, to give any third party,  for a charge no more than your
 161       cost of  physically performing source distribution,  a complete
 162       machine-readable copy  of the corresponding source  code, to be
 163       distributed under  the terms  of Sections  1 and  2 above  on a
 164       medium customarily used for software interchange; or,
 165
 166    c) Accompany it with the information  you received as to the offer
 167       to distribute  corresponding source code. (This  alternative is
 168       allowed  only for  noncommercial distribution  and only  if you
 169       received the  program in  object code  or executable  form with
 170       such an offer, in accord with Subsection b above.)
 171
 172    The source  code for a work  means the preferred form  of the work
 173    for making modifications  to it. For an  executable work, complete
 174    source code means all the source code for all modules it contains,
 175    plus any  associated interface definition files,  plus the scripts
 176    used   to   control   compilation    and   installation   of   the
 177    executable.  However,  as a  special  exception,  the source  code
 178    distributed need not include anything that is normally distributed
 179    (in  either  source or  binary  form)  with the  major  components
 180    (compiler, kernel, and so on) of the operating system on which the
 181    executable  runs, unless  that  component  itself accompanies  the
 182    executable.
 183
 184    If distribution of  executable or object code is  made by offering
 185    access to copy  from a designated place,  then offering equivalent
 186    access  to copy  the source  code from  the same  place counts  as
 187    distribution of the source code, even though third parties are not
 188    compelled to copy the source along with the object code.
 189
 190 4. You may  not copy, modify,  sublicense, or distribute  the Program
 191    except  as  expressly provided  under  this  License. Any  attempt
 192    otherwise to copy, modify, sublicense or distribute the Program is
 193    void,  and will  automatically  terminate your  rights under  this
 194    License.  However, parties  who have  received copies,  or rights,
 195    from  you  under  this  License   will  not  have  their  licenses
 196    terminated so long as such parties remain in full compliance.
 197
 198 5. You are  not required to accept  this License, since you  have not
 199    signed it. However,  nothing else grants you  permission to modify
 200    or distribute the  Program or its derivative  works. These actions
 201    are   prohibited   by   law   if    you   do   not   accept   this
 202    License. Therefore,  by modifying or distributing  the Program (or
 203    any work  based on the  Program), you indicate your  acceptance of
 204    this  License to  do  so, and  all its  terms  and conditions  for
 205    copying, distributing or  modifying the Program or  works based on
 206    it.
 207
 208 6. Each time you  redistribute the Program (or any work  based on the
 209    Program), the recipient automatically  receives a license from the
 210    original  licensor  to  copy,  distribute or  modify  the  Program
 211    subject  to these  terms and  conditions. You  may not  impose any
 212    further  restrictions on  the recipients'  exercise of  the rights
 213    granted herein.  You are  not responsible for enforcing compliance
 214    by third parties to this License.
 215
 216 7. If, as a  consequence of a court judgment or  allegation of patent
 217    infringement  or  for any  other  reason  (not limited  to  patent
 218    issues), conditions  are imposed on  you (whether by  court order,
 219    agreement  or otherwise)  that contradict  the conditions  of this
 220    License,  they do  not  excuse  you from  the  conditions of  this
 221    License.  If you cannot distribute so as to satisfy simultaneously
 222    your  obligations  under  this  License and  any  other  pertinent
 223    obligations,  then as  a consequence  you may  not distribute  the
 224    Program at all. For example, if  a patent license would not permit
 225    royalty-free  redistribution  of  the  Program by  all  those  who
 226    receive copies directly  or indirectly through you,  then the only
 227    way you could satisfy both it and this License would be to refrain
 228    entirely from distribution of the Program.
 229
 230    If any  portion of this  section is held invalid  or unenforceable
 231    under any particular  circumstance, the balance of  the section is
 232    intended to apply and the section  as a whole is intended to apply
 233    in other circumstances.
 234
 235    It is  not the purpose of  this section to induce  you to infringe
 236    any patents or other property  right claims or to contest validity
 237    of  any  such  claims;  this  section  has  the  sole  purpose  of
 238    protecting the integrity of the free software distribution system,
 239    which is implemented by public license practices. Many people have
 240    made  generous  contributions  to   the  wide  range  of  software
 241    distributed  through   that  system  in  reliance   on  consistent
 242    application of that system; it is up to the author/donor to decide
 243    if he or  she is willing to distribute software  through any other
 244    system and a licensee cannot impose that choice.
 245
 246    This section is intended to make thoroughly clear what is believed
 247    to be a consequence of the rest of this License.
 248
 249 8. If the  distribution and/or  use of the  Program is  restricted in
 250    certain countries either by  patents or by copyrighted interfaces,
 251    the original  copyright holder who  places the Program  under this
 252    License may  add an explicit geographical  distribution limitation
 253    excluding those countries, so  that distribution is permitted only
 254    in  or among  countries  not  thus excluded.  In  such case,  this
 255    License incorporates the  limitation as if written in  the body of
 256    this License.
 257
 258 9. The  Free  Software  Foundation  may publish  revised  and/or  new
 259    versions of the General Public License from time to time. Such new
 260    versions will be similar in spirit to the present version, but may
 261    differ in detail to address new problems or concerns.
 262
 263    Each  version is  given a  distinguishing version  number. If  the
 264    Program specifies a  version number of this  License which applies
 265    to it  and "any later version",  you have the option  of following
 266    the terms  and conditions either of  that version or of  any later
 267    version published by the Free  Software Foundation. If the Program
 268    does not specify a version number  of this License, you may choose
 269    any version ever published by the Free Software Foundation.
 270
 271 10. If you wish  to incorporate parts of the Program  into other free
 272     programs whose  distribution conditions  are different,  write to
 273     the  author  to  ask  for   permission.  For  software  which  is
 274     copyrighted by  the Free Software  Foundation, write to  the Free
 275     Software Foundation;  we sometimes make exceptions  for this. Our
 276     decision will be  guided by the two goals of  preserving the free
 277     status of all  derivatives of our free software  and of promoting
 278     the sharing and reuse of software generally.
 279
 280 **NO WARRANTY**
 281
 282 11. BECAUSE  THE PROGRAM  IS LICENSED  FREE  OF CHARGE,  THERE IS  NO
 283     WARRANTY FOR THE  PROGRAM, TO THE EXTENT  PERMITTED BY APPLICABLE
 284     LAW.   EXCEPT  WHEN OTHERWISE  STATED  IN  WRITING THE  COPYRIGHT
 285     HOLDERS AND/OR OTHER PARTIES PROVIDE  THE PROGRAM "AS IS" WITHOUT
 286     WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT
 287     NOT  LIMITED TO,  THE IMPLIED  WARRANTIES OF  MERCHANTABILITY AND
 288     FITNESS  FOR A  PARTICULAR PURPOSE.  THE  ENTIRE RISK  AS TO  THE
 289     QUALITY AND  PERFORMANCE OF THE  PROGRAM IS WITH YOU.  SHOULD THE
 290     PROGRAM PROVE  DEFECTIVE, YOU  ASSUME THE  COST OF  ALL NECESSARY
 291     SERVICING, REPAIR OR CORRECTION.
 292
 293 12. IN NO  EVENT UNLESS REQUIRED  BY APPLICABLE  LAW OR AGREED  TO IN
 294     WRITING WILL  ANY COPYRIGHT  HOLDER, OR ANY  OTHER PARTY  WHO MAY
 295     MODIFY  AND/OR REDISTRIBUTE  THE PROGRAM  AS PERMITTED  ABOVE, BE
 296     LIABLE  TO  YOU  FOR  DAMAGES, INCLUDING  ANY  GENERAL,  SPECIAL,
 297     INCIDENTAL OR  CONSEQUENTIAL DAMAGES  ARISING OUT  OF THE  USE OR
 298     INABILITY TO USE  THE PROGRAM (INCLUDING BUT NOT  LIMITED TO LOSS
 299     OF DATA OR DATA BEING  RENDERED INACCURATE OR LOSSES SUSTAINED BY
 300     YOU OR THIRD PARTIES OR A  FAILURE OF THE PROGRAM TO OPERATE WITH
 301     ANY OTHER PROGRAMS), EVEN IF SUCH  HOLDER OR OTHER PARTY HAS BEEN
 302     ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 303
 304
 305 END OF TERMS AND CONDITIONS
 306 ===========================
 307
 308
 309 How to Apply These Terms to Your New Programs
 310 =============================================
 311
 312 If you develop a  new program, and you want it to  be of the greatest
 313 possible use to the  public, the best way to achieve  this is to make
 314 it free  software which  everyone can  redistribute and  change under
 315 these terms.
 316
 317 To do so,  attach the following notices to the  program. It is safest
 318 to attach them  to the start of each source  file to most effectively
 319 convey the exclusion of warranty; and  each file should have at least
 320 the "copyright" line and a pointer to where the full notice is found.
 321
 322     one line to give the program's name  and an idea of what it does.
 323     Copyright (C) yyyy name of author
 324
 325     This program  is free  software; you  can redistribute  it and/or
 326     modify it  under the terms of  the GNU General Public  License as
 327     published by  the Free Software  Foundation; either version  2 of
 328     the License, or (at your option) any later version.
 329
 330     This program is  distributed in the hope that it  will be useful,
 331     but WITHOUT  ANY WARRANTY; without  even the implied  warranty of
 332     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 333     General Public License for more details.
 334
 335     You should have received a copy of the GNU General Public License
 336     along  with this  program; if  not,  write to  the Free  Software
 337     Foundation,  Inc., 51  Franklin Street,  Fifth Floor,  Boston, MA
 338     02110-1301, USA.
 339
 340 Also add  information on how to  contact you by electronic  and paper
 341 mail.
 342
 343 If the  program is interactive,  make it  output a short  notice like
 344 this when it starts in an interactive mode: ::
 345
 346     Gnomovision  version  69,  Copyright  (C)  year  name  of  author
 347     Gnomovision comes  with ABSOLUTELY NO WARRANTY;  for details type
 348     "show  w".   This  is  free  software, and  you  are  welcome  to
 349     redistribute  it  under certain  conditions;  "type  show c"  for
 350     details.
 351
 352 The hypothetical commands ``"show w"`` and ``"show c"`` should show
 353 the appropriate parts of the General Public License.  Of course, the
 354 commands you use may be called something other than ``"show w"`` and
 355 ``"show c"``; they could even be mouse-clicks or menu items--whatever
 356 suits your program.
 357
 358 You should  also get your employer  (if you work as  a programmer) or
 359 your  school,  if any,  to  sign  a  "copyright disclaimer"  for  the
 360 program, if necessary. Here is a sample; alter the names: ::
 361
 362     Yoyodyne, Inc., hereby disclaims all copyright
 363     interest in the program `Gnomovision`
 364     (which makes passes at compilers) written
 365     by James Hacker.
 366
 367     signature of Ty Coon, 1 April 1989
 368     Ty Coon, President of Vice
 369
 370 This  General  Public  License  does not  permit  incorporating  your
 371 program into  proprietary programs. If  your program is  a subroutine
 372 library,  you  may   consider  it  more  useful   to  permit  linking
 373 proprietary applications with  the library. If this is  what you want
 374 to     do,     use     the     [GNU     Lesser     General     Public
 375 License](https://www.gnu.org/licenses/lgpl.html)   instead  of   this
 376 License.