GNU GENERAL PUBLIC LICENSE
Version 3, 29 June 2007
Copyright © 2007 Free Software Foundation, Inc. <https://fsf.org/>
Everyone is permitted to copy and distribute verbatim copies of this license
document, but changing it is not allowed.
The GNU General Public License is a free, copyleft license for software and
other kinds of works.
The licenses for most software and other practical works are designed to take
away your freedom to share and change the works. By contrast, the GNU General
Public License is intended to guarantee your freedom to share and change all
versions of a program--to make sure it remains free software for all its users.
We, the Free Software Foundation, use the GNU General Public License for most
of our software; it applies also to any other work released this way by its
authors. You can apply it to your programs, too.
When we speak of free software, we are referring to freedom, not price. Our
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To protect your rights, we need to prevent others from denying you these rights
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Developers that use the GNU GPL protect your rights with two steps: (1) assert
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The precise terms and conditions for copying, distribution and modification
TERMS AND CONDITIONS
"This License" refers to version 3 of the GNU General Public License.
"Copyright" also means copyright-like laws that apply to other kinds of works,
such as semiconductor masks.
"The Program" refers to any copyrightable work licensed under this License.
Each licensee is addressed as "you". "Licensees" and "recipients" may be individuals
To "modify" a work means to copy from or adapt all or part of the work in
a fashion requiring copyright permission, other than the making of an exact
copy. The resulting work is called a "modified version" of the earlier work
or a work "based on" the earlier work.
A "covered work" means either the unmodified Program or a work based on the
To "propagate" a work means to do anything with it that, without permission,
would make you directly or secondarily liable for infringement under applicable
copyright law, except executing it on a computer or modifying a private copy.
Propagation includes copying, distribution (with or without modification),
making available to the public, and in some countries other activities as
To "convey" a work means any kind of propagation that enables other parties
to make or receive copies. Mere interaction with a user through a computer
network, with no transfer of a copy, is not conveying.
An interactive user interface displays "Appropriate Legal Notices" to the
extent that it includes a convenient and prominently visible feature that
(1) displays an appropriate copyright notice, and (2) tells the user that
there is no warranty for the work (except to the extent that warranties are
provided), that licensees may convey the work under this License, and how
to view a copy of this License. If the interface presents a list of user commands
or options, such as a menu, a prominent item in the list meets this criterion.
1. Source Code.
The "source code" for a work means the preferred form of the work for making
modifications to it. "Object code" means any non-source form of a work.
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defined by a recognized standards body, or, in the case of interfaces specified
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The "System Libraries" of an executable work include anything, other than
the work as a whole, that (a) is included in the normal form of packaging
a Major Component, but which is not part of that Major Component, and (b)
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a Standard Interface for which an implementation is available to the public
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component (kernel, window system, and so on) of the specific operating system
(if any) on which the executable work runs, or a compiler used to produce
the work, or an object code interpreter used to run it.
The "Corresponding Source" for a work in object code form means all the source
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code and to modify the work, including scripts to control those activities.
However, it does not include the work's System Libraries, or general-purpose
tools or generally available free programs which are used unmodified in performing
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Source includes interface definition files associated with source files for
the work, and the source code for shared libraries and dynamically linked
subprograms that the work is specifically designed to require, such as by
intimate data communication or control flow between those subprograms and
other parts of the work.
The Corresponding Source need not include anything that users can regenerate
automatically from other parts of the Corresponding Source.
The Corresponding Source for a work in source code form is that same work.
2. Basic Permissions.
All rights granted under this License are granted for the term of copyright
on the Program, and are irrevocable provided the stated conditions are met.
This License explicitly affirms your unlimited permission to run the unmodified
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only if the output, given its content, constitutes a covered work. This License
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You may make, run and propagate covered works that you do not convey, without
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copyright treaty adopted on 20 December 1996, or similar laws prohibiting
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you disclaim any intention to limit operation or modification of the work
as a means of enforcing, against the work's users, your or third parties'
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4. Conveying Verbatim Copies.
You may convey verbatim copies of the Program's source code as you receive
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You may convey a work based on the Program, or the modifications to produce
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with any applicable section 7 additional terms, to the whole of the work,
and all its parts, regardless of how they are packaged. This License gives
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Legal Notices; however, if the Program has interactive interfaces that do
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A compilation of a covered work with other separate and independent works,
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not combined with it such as to form a larger program, in or on a volume of
a storage or distribution medium, is called an "aggregate" if the compilation
and its resulting copyright are not used to limit the access or legal rights
of the compilation's users beyond what the individual works permit. Inclusion
of a covered work in an aggregate does not cause this License to apply to
the other parts of the aggregate.
6. Conveying Non-Source Forms.
You may convey a covered work in object code form under the terms of sections
4 and 5, provided that you also convey the machine-readable Corresponding
Source under the terms of this License, in one of these ways:
a) Convey the object code in, or embodied in, a physical product (including
a physical distribution medium), accompanied by the Corresponding Source fixed
on a durable physical medium customarily used for software interchange.
b) Convey the object code in, or embodied in, a physical product (including
a physical distribution medium), accompanied by a written offer, valid for
at least three years and valid for as long as you offer spare parts or customer
support for that product model, to give anyone who possesses the object code
either (1) a copy of the Corresponding Source for all the software in the
product that is covered by this License, on a durable physical medium customarily
used for software interchange, for a price no more than your reasonable cost
of physically performing this conveying of source, or (2) access to copy the
Corresponding Source from a network server at no charge.
c) Convey individual copies of the object code with a copy of the written
offer to provide the Corresponding Source. This alternative is allowed only
occasionally and noncommercially, and only if you received the object code
with such an offer, in accord with subsection 6b.
d) Convey the object code by offering access from a designated place (gratis
or for a charge), and offer equivalent access to the Corresponding Source
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require recipients to copy the Corresponding Source along with the object
code. If the place to copy the object code is a network server, the Corresponding
Source may be on a different server (operated by you or a third party) that
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the object code work.
A "User Product" is either (1) a "consumer product", which means any tangible
personal property which is normally used for personal, family, or household
purposes, or (2) anything designed or sold for incorporation into a dwelling.
In determining whether a product is a consumer product, doubtful cases shall
be resolved in favor of coverage. For a particular product received by a particular
user, "normally used" refers to a typical or common use of that class of product,
regardless of the status of the particular user or of the way in which the
particular user actually uses, or expects or is expected to use, the product.
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only significant mode of use of the product.
"Installation Information" for a User Product means any methods, procedures,
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versions of a covered work in that User Product from a modified version of
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continued functioning of the modified object code is in no case prevented
or interfered with solely because modification has been made.
If you convey an object code work under this section in, or with, or specifically
for use in, a User Product, and the conveying occurs as part of a transaction
in which the right of possession and use of the User Product is transferred
to the recipient in perpetuity or for a fixed term (regardless of how the
transaction is characterized), the Corresponding Source conveyed under this
section must be accompanied by the Installation Information. But this requirement
does not apply if neither you nor any third party retains the ability to install
modified object code on the User Product (for example, the work has been installed
The requirement to provide Installation Information does not include a requirement
to continue to provide support service, warranty, or updates for a work that
has been modified or installed by the recipient, or for the User Product in
which it has been modified or installed. Access to a network may be denied
when the modification itself materially and adversely affects the operation
of the network or violates the rules and protocols for communication across
Corresponding Source conveyed, and Installation Information provided, in accord
with this section must be in a format that is publicly documented (and with
an implementation available to the public in source code form), and must require
no special password or key for unpacking, reading or copying.
7. Additional Terms.
"Additional permissions" are terms that supplement the terms of this License
by making exceptions from one or more of its conditions. Additional permissions
that are applicable to the entire Program shall be treated as though they
were included in this License, to the extent that they are valid under applicable
law. If additional permissions apply only to part of the Program, that part
may be used separately under those permissions, but the entire Program remains
governed by this License without regard to the additional permissions.
When you convey a copy of a covered work, you may at your option remove any
additional permissions from that copy, or from any part of it. (Additional
permissions may be written to require their own removal in certain cases when
you modify the work.) You may place additional permissions on material, added
by you to a covered work, for which you have or can give appropriate copyright
Notwithstanding any other provision of this License, for material you add
to a covered work, you may (if authorized by the copyright holders of that
material) supplement the terms of this License with terms:
a) Disclaiming warranty or limiting liability differently from the terms of
sections 15 and 16 of this License; or
b) Requiring preservation of specified reasonable legal notices or author
attributions in that material or in the Appropriate Legal Notices displayed
by works containing it; or
c) Prohibiting misrepresentation of the origin of that material, or requiring
that modified versions of such material be marked in reasonable ways as different
from the original version; or
d) Limiting the use for publicity purposes of names of licensors or authors
of the material; or
e) Declining to grant rights under trademark law for use of some trade names,
trademarks, or service marks; or
f) Requiring indemnification of licensors and authors of that material by
anyone who conveys the material (or modified versions of it) with contractual
assumptions of liability to the recipient, for any liability that these contractual
assumptions directly impose on those licensors and authors.
All other non-permissive additional terms are considered "further restrictions"
within the meaning of section 10. If the Program as you received it, or any
part of it, contains a notice stating that it is governed by this License
along with a term that is a further restriction, you may remove that term.
If a license document contains a further restriction but permits relicensing
or conveying under this License, you may add to a covered work material governed
by the terms of that license document, provided that the further restriction
does not survive such relicensing or conveying.
If you add terms to a covered work in accord with this section, you must place,
in the relevant source files, a statement of the additional terms that apply
to those files, or a notice indicating where to find the applicable terms.
Additional terms, permissive or non-permissive, may be stated in the form
of a separately written license, or stated as exceptions; the above requirements
apply either way.
You may not propagate or modify a covered work except as expressly provided
under this License. Any attempt otherwise to propagate or modify it is void,
and will automatically terminate your rights under this License (including
any patent licenses granted under the third paragraph of section 11).
However, if you cease all violation of this License, then your license from
a particular copyright holder is reinstated (a) provisionally, unless and
until the copyright holder explicitly and finally terminates your license,
and (b) permanently, if the copyright holder fails to notify you of the violation
by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently
if the copyright holder notifies you of the violation by some reasonable means,
this is the first time you have received notice of violation of this License
(for any work) from that copyright holder, and you cure the violation prior
to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses
of parties who have received copies or rights from you under this License.
If your rights have been terminated and not permanently reinstated, you do
not qualify to receive new licenses for the same material under section 10.
9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or run a copy
of the Program. Ancillary propagation of a covered work occurring solely as
a consequence of using peer-to-peer transmission to receive a copy likewise
does not require acceptance. However, nothing other than this License grants
you permission to propagate or modify any covered work. These actions infringe
copyright if you do not accept this License. Therefore, by modifying or propagating
a covered work, you indicate your acceptance of this License to do so.
10. Automatic Licensing of Downstream Recipients.
Each time you convey a covered work, the recipient automatically receives
a license from the original licensors, to run, modify and propagate that work,
subject to this License. You are not responsible for enforcing compliance
by third parties with this License.
An "entity transaction" is a transaction transferring control of an organization,
or substantially all assets of one, or subdividing an organization, or merging
organizations. If propagation of a covered work results from an entity transaction,
each party to that transaction who receives a copy of the work also receives
whatever licenses to the work the party's predecessor in interest had or could
give under the previous paragraph, plus a right to possession of the Corresponding
Source of the work from the predecessor in interest, if the predecessor has
it or can get it with reasonable efforts.
You may not impose any further restrictions on the exercise of the rights
granted or affirmed under this License. For example, you may not impose a
license fee, royalty, or other charge for exercise of rights granted under
this License, and you may not initiate litigation (including a cross-claim
or counterclaim in a lawsuit) alleging that any patent claim is infringed
by making, using, selling, offering for sale, or importing the Program or
any portion of it.
A "contributor" is a copyright holder who authorizes use under this License
of the Program or a work on which the Program is based. The work thus licensed
is called the contributor's "contributor version".
A contributor's "essential patent claims" are all patent claims owned or controlled
by the contributor, whether already acquired or hereafter acquired, that would
be infringed by some manner, permitted by this License, of making, using,
or selling its contributor version, but do not include claims that would be
infringed only as a consequence of further modification of the contributor
version. For purposes of this definition, "control" includes the right to
grant patent sublicenses in a manner consistent with the requirements of this
Each contributor grants you a non-exclusive, worldwide, royalty-free patent
license under the contributor's essential patent claims, to make, use, sell,
offer for sale, import and otherwise run, modify and propagate the contents
of its contributor version.
In the following three paragraphs, a "patent license" is any express agreement
or commitment, however denominated, not to enforce a patent (such as an express
permission to practice a patent or covenant not to sue for patent infringement).
To "grant" such a patent license to a party means to make such an agreement
or commitment not to enforce a patent against the party.
If you convey a covered work, knowingly relying on a patent license, and the
Corresponding Source of the work is not available for anyone to copy, free
of charge and under the terms of this License, through a publicly available
network server or other readily accessible means, then you must either (1)
cause the Corresponding Source to be so available, or (2) arrange to deprive
yourself of the benefit of the patent license for this particular work, or
(3) arrange, in a manner consistent with the requirements of this License,
to extend the patent license to downstream recipients. "Knowingly relying"
means you have actual knowledge that, but for the patent license, your conveying
the covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that country
that you have reason to believe are valid.
If, pursuant to or in connection with a single transaction or arrangement,
you convey, or propagate by procuring conveyance of, a covered work, and grant
a patent license to some of the parties receiving the covered work authorizing
them to use, propagate, modify or convey a specific copy of the covered work,
then the patent license you grant is automatically extended to all recipients
of the covered work and works based on it.
A patent license is "discriminatory" if it does not include within the scope
of its coverage, prohibits the exercise of, or is conditioned on the non-exercise
of one or more of the rights that are specifically granted under this License.
You may not convey a covered work if you are a party to an arrangement with
a third party that is in the business of distributing software, under which
you make payment to the third party based on the extent of your activity of
conveying the work, and under which the third party grants, to any of the
parties who would receive the covered work from you, a discriminatory patent
license (a) in connection with copies of the covered work conveyed by you
(or copies made from those copies), or (b) primarily for and in connection
with specific products or compilations that contain the covered work, unless
you entered into that arrangement, or that patent license was granted, prior
to 28 March 2007.
Nothing in this License shall be construed as excluding or limiting any implied
license or other defenses to infringement that may otherwise be available
to you under applicable patent law.
12. No Surrender of Others' Freedom.
If conditions are imposed on you (whether by court order, agreement or otherwise)
that contradict the conditions of this License, they do not excuse you from
the conditions of this License. If you cannot convey a covered work so as
to satisfy simultaneously your obligations under this License and any other
pertinent obligations, then as a consequence you may not convey it at all.
For example, if you agree to terms that obligate you to collect a royalty
for further conveying from those to whom you convey the Program, the only
way you could satisfy both those terms and this License would be to refrain
entirely from conveying the Program.
13. Use with the GNU Affero General Public License.
Notwithstanding any other provision of this License, you have permission to
link or combine any covered work with a work licensed under version 3 of the
GNU Affero General Public License into a single combined work, and to convey
the resulting work. The terms of this License will continue to apply to the
part which is the covered work, but the special requirements of the GNU Affero
General Public License, section 13, concerning interaction through a network
will apply to the combination as such.
14. Revised Versions of this License.
The Free Software Foundation may publish revised and/or new versions of the
GNU General Public License from time to time. Such new versions will be similar
in spirit to the present version, but may differ in detail to address new
problems or concerns.
Each version is given a distinguishing version number. If the Program specifies
that a certain numbered version of the GNU General Public License "or any
later version" applies to it, you have the option of following the terms and
conditions either of that numbered version or of any later version published
by the Free Software Foundation. If the Program does not specify a version
number of the GNU General Public License, you may choose any version ever
published by the Free Software Foundation.
If the Program specifies that a proxy can decide which future versions of
the GNU General Public License can be used, that proxy's public statement
of acceptance of a version permanently authorizes you to choose that version
for the Program.
Later license versions may give you additional or different permissions. However,
no additional obligations are imposed on any author or copyright holder as
a result of your choosing to follow a later version.
15. Disclaimer of Warranty.
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE
LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM
PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR
16. Limitation of Liability.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL
ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM
AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO
USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED
INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE
PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER
PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
17. Interpretation of Sections 15 and 16.
If the disclaimer of warranty and limitation of liability provided above cannot
be given local legal effect according to their terms, reviewing courts shall
apply local law that most closely approximates an absolute waiver of all civil
liability in connection with the Program, unless a warranty or assumption
of liability accompanies a copy of the Program in return for a fee. END OF
TERMS AND CONDITIONS
How to Apply These Terms to Your New Programs
If you develop a new program, and you want it to be of the greatest possible
use to the public, the best way to achieve this is to make it free software
which everyone can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest to attach
them to the start of each source file to most effectively state the exclusion
of warranty; and each file should have at least the "copyright" line and a
pointer to where the full notice is found.
<one line to give the program's name and a brief idea of what it does.>
Copyright (C) <year> <name of author>
This program is free software: you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
this program. If not, see <https://www.gnu.org/licenses/>.
Also add information on how to contact you by electronic and paper mail.
If the program does terminal interaction, make it output a short notice like
this when it starts in an interactive mode:
<program> Copyright (C) <year> <name of author>
This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
This is free software, and you are welcome to redistribute it under certain
conditions; type `show c' for details.
The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License. Of course, your program's commands might
be different; for a GUI interface, you would use an "about box".
You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary. For
more information on this, and how to apply and follow the GNU GPL, see <https://www.gnu.org/licenses/>.
The GNU General Public License does not permit incorporating your program
into proprietary programs. If your program is a subroutine library, you may
consider it more useful to permit linking proprietary applications with the
library. If this is what you want to do, use the GNU Lesser General Public
License instead of this License. But first, please read <https://www.gnu.org/