Re: FWD: Copyright in LGPL projects

2024-03-05 Thread Fred

PLEASE REMOVE ME FROM ALL LISTS!

I tried to remove myself. It didn't work.

I tried to contact the list admin. I did not get an answer.

I'M GONNA SPAM YOUR LISTS UNTIL YOU REMOVE ME!


On 05.03.24 22:15, Alan M Varghese wrote:

Soren,


 ... but it is also perfectly fine to ship them in the same file.

I think what Wookey is referring to is that GPL and LGPL licenses contain
a line that says something like:
'Copyright (C) 1991, 1999 Free Software Foundation, Inc.'
I believe this copyright refers to the text of the license itself. 
Hence, it

might not be a good idea to include a second copyright in this same file.

So, including the copyright and license in the same file can work for 
licenses

like MIT, BSD etc which does not mention a copyright of its own, and not
for GPL-like licenses which includes a copyright line as part of the 
license.


Anyways, upstream author has added a new file called "COPYRIGHT" in 
the root
of the project[1] that mentions the copyright years, owner and the 
license used.
Based on all our discussion so far, I understand this should be 
acceptable

for our purposes in Debian.

[1] https://github.com/hyprwm/hyprlang/blob/main/COPYRIGHT

Alan

On 3/6/24 02:19, Soren Stoutner wrote:

Wookey,

On Tuesday, March 5, 2024 2:51:10 AM MST Wookey wrote:

On 2024-03-04 11:19 -0700, Soren Stoutner wrote:

Alan,

These are good questions.

1.  Yes, there must be a copyright statement.  Only the person, 
people,
group, or organization that holds the copyright can issue a license 
for

other people to use the work.  So, you must have someone claiming a
copyright or they do not have the legal ability to release the work to
others under the LGPL.

But what requires that to be in the source tarball? Copyright is
intrinsic in the authors, it doesn't require a statement to create
it. Said authors _do_ need to specify a licence (and the LGPL requires
that licence text to be shipped in the source (I think, although I
could only actually find this requirement for a 'Combined work' and in
the FAQ just now)).

_Debian_ requires a copyright statement (in the copyright file) so we
do need to find out from the project what to put, and a statement in
the source would be a good way to communicate that, but a notice on
the project website or even an email from a representative would also
do the job.


That is correct.  There must be a copyright statement or the license
information is not legally valid (because only someone who claims 
copyright
can issue a license).  However, it doesn’t expressly need to be in 
the tarball

(see below).  That part is simply best practice, because it maintain the
copyright information if the project is forked or upstream 
disappears, which
otherwise can be difficult to determine if it was only on a website 
that is now

defunct or in an email sent to a Debian developer who is no longer
participating in the project.

So, there is a distinction between what is the minimum legal 
requirement and

what is best practice.

My recommendation would be that you communicate to the upstream 
project

that
they need to include the copyright and licensing information in the 
root

of
their repository, preferably all in one file, as a minimum 
requirement for

you to be willing to package their project in Debian.


I don't think this is correct. And we should be happy to package
anything which is actually free software. We don't get to impose extra
requirements before we will package something.


As pointed out above, there is a distinction between what is the minimum
requirement for packaging in Debian and best practice.  I carefully 
worded

point 2 in my original email to state that, if **I** were packaging this
software, I would communicate with upstream that if they wanted 
**me** to
package their software in Debian, my minimum requirement would be 
that they
explicitly state the copyright information in the source code. 
Originally I
had a point 3, which I deleted before sending the email, explaining 
that my
personal preference for when I would be willing to package software 
is higher
than Debian’s requirement, and that a website notation or email 
communication
of copyright has been used in some packages in the past, but with the 
downside
described above.  I took out point 3 because I felt it muddied the 
waters, but

since the point has been brought up, it is worth discussing.


They should put a copy of the LGPL in (in a file called 'COPYING' or
'LICENCE' by convention) (if this isn't done already).  A copyright
notice for the project should _not_ go in the same file (The LGPL
already has one for the LGPL authorship itself, so this is probably
the only file in the distribution which should definitiely _not_ have
the project copyright notice). It should ideally be a header on at 
least

one source file, (preferably all of them), but could be any README, or
even just a notice on the project website, or an email saying '


I must disagree with you on this point.  It is 

Re: FWD: Copyright in LGPL projects

2024-03-05 Thread Alan M Varghese

Soren,


 ... but it is also perfectly fine to ship them in the same file.

I think what Wookey is referring to is that GPL and LGPL licenses contain
a line that says something like:
'Copyright (C) 1991, 1999 Free Software Foundation, Inc.'
I believe this copyright refers to the text of the license itself. Hence, it
might not be a good idea to include a second copyright in this same file.

So, including the copyright and license in the same file can work for licenses
like MIT, BSD etc which does not mention a copyright of its own, and not
for GPL-like licenses which includes a copyright line as part of the license.

Anyways, upstream author has added a new file called "COPYRIGHT" in the root
of the project[1] that mentions the copyright years, owner and the license used.
Based on all our discussion so far, I understand this should be acceptable
for our purposes in Debian.

[1] https://github.com/hyprwm/hyprlang/blob/main/COPYRIGHT

Alan

On 3/6/24 02:19, Soren Stoutner wrote:

Wookey,

On Tuesday, March 5, 2024 2:51:10 AM MST Wookey wrote:

On 2024-03-04 11:19 -0700, Soren Stoutner wrote:

Alan,

These are good questions.

1.  Yes, there must be a copyright statement.  Only the person, people,
group, or organization that holds the copyright can issue a license for
other people to use the work.  So, you must have someone claiming a
copyright or they do not have the legal ability to release the work to
others under the LGPL.

But what requires that to be in the source tarball? Copyright is
intrinsic in the authors, it doesn't require a statement to create
it. Said authors _do_ need to specify a licence (and the LGPL requires
that licence text to be shipped in the source (I think, although I
could only actually find this requirement for a 'Combined work' and in
the FAQ just now)).

_Debian_ requires a copyright statement (in the copyright file) so we
do need to find out from the project what to put, and a statement in
the source would be a good way to communicate that, but a notice on
the project website or even an email from a representative would also
do the job.


That is correct.  There must be a copyright statement or the license
information is not legally valid (because only someone who claims copyright
can issue a license).  However, it doesn’t expressly need to be in the tarball
(see below).  That part is simply best practice, because it maintain the
copyright information if the project is forked or upstream disappears, which
otherwise can be difficult to determine if it was only on a website that is now
defunct or in an email sent to a Debian developer who is no longer
participating in the project.

So, there is a distinction between what is the minimum legal requirement and
what is best practice.


My recommendation would be that you communicate to the upstream project

that

they need to include the copyright and licensing information in the root

of

their repository, preferably all in one file, as a minimum requirement for
you to be willing to package their project in Debian.


I don't think this is correct. And we should be happy to package
anything which is actually free software. We don't get to impose extra
requirements before we will package something.


As pointed out above, there is a distinction between what is the minimum
requirement for packaging in Debian and best practice.  I carefully worded
point 2 in my original email to state that, if **I** were packaging this
software, I would communicate with upstream that if they wanted **me** to
package their software in Debian, my minimum requirement would be that they
explicitly state the copyright information in the source code.  Originally I
had a point 3, which I deleted before sending the email, explaining that my
personal preference for when I would be willing to package software is higher
than Debian’s requirement, and that a website notation or email communication
of copyright has been used in some packages in the past, but with the downside
described above.  I took out point 3 because I felt it muddied the waters, but
since the point has been brought up, it is worth discussing.


They should put a copy of the LGPL in (in a file called 'COPYING' or
'LICENCE' by convention) (if this isn't done already).  A copyright
notice for the project should _not_ go in the same file (The LGPL
already has one for the LGPL authorship itself, so this is probably
the only file in the distribution which should definitiely _not_ have
the project copyright notice). It should ideally be a header on at least
one source file, (preferably all of them), but could be any README, or
even just a notice on the project website, or an email saying '


I must disagree with you on this point.  It is perfectly fine to ship the
copyright and the license in two separate files, but it is also perfectly fine
to ship them in the same file.  I do so in my upstream project linked in a
previous email, and Debian does so in debian/copyright.  Using a file named
LICENSE or 

Re: FWD: Copyright in LGPL projects

2024-03-05 Thread Soren Stoutner
Wookey,

On Tuesday, March 5, 2024 2:51:10 AM MST Wookey wrote:
> On 2024-03-04 11:19 -0700, Soren Stoutner wrote:
> > Alan,
> > 
> > These are good questions.
> > 
> > 1.  Yes, there must be a copyright statement.  Only the person, people,
> > group, or organization that holds the copyright can issue a license for
> > other people to use the work.  So, you must have someone claiming a
> > copyright or they do not have the legal ability to release the work to
> > others under the LGPL.
> But what requires that to be in the source tarball? Copyright is
> intrinsic in the authors, it doesn't require a statement to create
> it. Said authors _do_ need to specify a licence (and the LGPL requires
> that licence text to be shipped in the source (I think, although I
> could only actually find this requirement for a 'Combined work' and in
> the FAQ just now)).
>
> _Debian_ requires a copyright statement (in the copyright file) so we
> do need to find out from the project what to put, and a statement in
> the source would be a good way to communicate that, but a notice on
> the project website or even an email from a representative would also
> do the job.

That is correct.  There must be a copyright statement or the license 
information is not legally valid (because only someone who claims copyright 
can issue a license).  However, it doesn’t expressly need to be in the tarball 
(see below).  That part is simply best practice, because it maintain the 
copyright information if the project is forked or upstream disappears, which 
otherwise can be difficult to determine if it was only on a website that is now 
defunct or in an email sent to a Debian developer who is no longer 
participating in the project.

So, there is a distinction between what is the minimum legal requirement and 
what is best practice.

> > My recommendation would be that you communicate to the upstream project 
that
> > they need to include the copyright and licensing information in the root 
of
> > their repository, preferably all in one file, as a minimum requirement for
> > you to be willing to package their project in Debian.
> 
> I don't think this is correct. And we should be happy to package
> anything which is actually free software. We don't get to impose extra
> requirements before we will package something.

As pointed out above, there is a distinction between what is the minimum  
requirement for packaging in Debian and best practice.  I carefully worded 
point 2 in my original email to state that, if **I** were packaging this 
software, I would communicate with upstream that if they wanted **me** to 
package their software in Debian, my minimum requirement would be that they 
explicitly state the copyright information in the source code.  Originally I 
had a point 3, which I deleted before sending the email, explaining that my 
personal preference for when I would be willing to package software is higher 
than Debian’s requirement, and that a website notation or email communication 
of copyright has been used in some packages in the past, but with the downside 
described above.  I took out point 3 because I felt it muddied the waters, but 
since the point has been brought up, it is worth discussing.

> They should put a copy of the LGPL in (in a file called 'COPYING' or
> 'LICENCE' by convention) (if this isn't done already).  A copyright
> notice for the project should _not_ go in the same file (The LGPL
> already has one for the LGPL authorship itself, so this is probably
> the only file in the distribution which should definitiely _not_ have
> the project copyright notice). It should ideally be a header on at least
> one source file, (preferably all of them), but could be any README, or
> even just a notice on the project website, or an email saying '

I must disagree with you on this point.  It is perfectly fine to ship the 
copyright and the license in two separate files, but it is also perfectly fine 
to ship them in the same file.  I do so in my upstream project linked in a 
previous email, and Debian does so in debian/copyright.  Using a file named 
LICENSE or COPYING or AUTHORS is fairly standard, but exactly how this is done 
doesn’t matter as long as both copyright (with years) and license are 
communicated.

-- 
Soren Stoutner
so...@debian.org

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Re: FWD: Copyright in LGPL projects

2024-03-05 Thread Wookey
On 2024-03-04 11:19 -0700, Soren Stoutner wrote:
> Alan,
> 
> These are good questions.
> 
> 1.  Yes, there must be a copyright statement.  Only the person, people, 
> group, 
> or organization that holds the copyright can issue a license for other people 
> to use the work.  So, you must have someone claiming a copyright or they do 
> not have the legal ability to release the work to others under the LGPL.

But what requires that to be in the source tarball? Copyright is
intrinsic in the authors, it doesn't require a statement to create
it. Said authors _do_ need to specify a licence (and the LGPL requires
that licence text to be shipped in the source (I think, although I
could only actually find this requirement for a 'Combined work' and in
the FAQ just now)).

_Debian_ requires a copyright statement (in the copyright file) so we
do need to find out from the project what to put, and a statement in
the source would be a good way to communicate that, but a notice on
the project website or even an email from a representative would also
do the job.

> My recommendation would be that you communicate to the upstream project that 
> they need to include the copyright and licensing information in the root of 
> their repository, preferably all in one file, as a minimum requirement for 
> you 
> to be willing to package their project in Debian.

I don't think this is correct. And we should be happy to package
anything which is actually free software. We don't get to impose extra
requirements before we will package something.

They should put a copy of the LGPL in (in a file called 'COPYING' or
'LICENCE' by convention) (if this isn't done already).  A copyright
notice for the project should _not_ go in the same file (The LGPL
already has one for the LGPL authorship itself, so this is probably
the only file in the distribution which should definitiely _not_ have
the project copyright notice). It should ideally be a header on at least
one source file, (preferably all of them), but could be any README, or
even just a notice on the project website, or an email saying '

Wookey
-- 
Principal hats:  Debian, Wookware, ARM
http://wookware.org/


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Re: FWD: Copyright in LGPL projects

2024-03-04 Thread Alan M Varghese

Thanks you for the confirmation. Really appreciate it!

They have added a copyright file; so it should be all good. I was likely being
overly cautious and they might have been too. It tripped me up when they 
indicated
(L)GPL might have to be treated differently, and when I looked up projects that 
used
LGPL, they seemed to follow a different style from say, BSD/MIT licensed ones.

On 3/5/24 11:32, Andrey Rahmatullin wrote:

There are no special formats for copyright files and the license shouldn't
matter so I'm still not sure what's the actual question they have.
In most software the top-level copyright is simply stated as one line in
the top-level LICENSE or whatever file or even in the top-level README,
and separate per-file copyrights are stated in the files themselves. The
calibre one you linked is very unusual




Re: FWD: Copyright in LGPL projects

2024-03-04 Thread Andrey Rahmatullin
On Tue, Mar 05, 2024 at 03:50:27AM +0530, Alan M Varghese wrote:
> What I meant was that upstream does not know where to put the copyright 
> information or
> how it should be formatted. Or, to rephrase, is there a preferred format for 
> a COPYRIGHT file
> in a project that uses LGPL?
There are no special formats for copyright files and the license shouldn't
matter so I'm still not sure what's the actual question they have.
In most software the top-level copyright is simply stated as one line in
the top-level LICENSE or whatever file or even in the top-level README,
and separate per-file copyrights are stated in the files themselves. The
calibre one you linked is very unusual.

-- 
WBR, wRAR


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Re: FWD: Copyright in LGPL projects

2024-03-04 Thread Alan M Varghese

What I meant was that upstream does not know where to put the copyright 
information or
how it should be formatted. Or, to rephrase, is there a preferred format for a 
COPYRIGHT file
in a project that uses LGPL?

This is the issue I opened upstream:
https://github.com/hyprwm/hyprlang/issues/28

On 3/5/24 01:38, Andrey Rahmatullin wrote:

On Tue, Mar 05, 2024 at 12:38:00AM +0530, Alan M Varghese wrote:

Hello Soren,

Thank you for answering my queries.

I will share this with the upstream project. The project authors are unsure how
to do this for an LGPL project. I will see tomorrow if I can find an example of
an LGPL project that includes the copyright information in the root of the 
project.
(I found a project that does this for GPL[1], but not for LGPL).

Why would that make a difference?





Re: FWD: Copyright in LGPL projects

2024-03-04 Thread Andrey Rahmatullin
On Tue, Mar 05, 2024 at 12:38:00AM +0530, Alan M Varghese wrote:
> Hello Soren,
> 
> Thank you for answering my queries.
> 
> I will share this with the upstream project. The project authors are unsure 
> how
> to do this for an LGPL project. I will see tomorrow if I can find an example 
> of
> an LGPL project that includes the copyright information in the root of the 
> project.
> (I found a project that does this for GPL[1], but not for LGPL).
Why would that make a difference?

-- 
WBR, wRAR


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Re: FWD: Copyright in LGPL projects

2024-03-04 Thread Alan M Varghese

Hello Soren,

Thank you for answering my queries.

I will share this with the upstream project. The project authors are unsure how
to do this for an LGPL project. I will see tomorrow if I can find an example of
an LGPL project that includes the copyright information in the root of the 
project.
(I found a project that does this for GPL[1], but not for LGPL).

[1] https://github.com/kovidgoyal/calibre/blob/master/COPYRIGHT

Regards,
Alan


On 3/4/24 23:49, Soren Stoutner wrote:

Alan,

These are good questions.

1.  Yes, there must be a copyright statement.  Only the person, people, group,
or organization that holds the copyright can issue a license for other people
to use the work.  So, you must have someone claiming a copyright or they do
not have the legal ability to release the work to others under the LGPL.

2.  No, it is not required that each individual file contain a copyright
statement or the header of the LGPL at the top.  The FSF recommends such as a
best practice, and I would agree that it is desirable, but it is not required.

My recommendation would be that you communicate to the upstream project that
they need to include the copyright and licensing information in the root of
their repository, preferably all in one file, as a minimum requirement for you
to be willing to package their project in Debian.

Soren

On Sunday, March 3, 2024 11:06:30 PM MST Alan M Varghese wrote:

Sent message incorrectly to debian-mentors-request instead of debian-

mentors.

Correcting.


 Forwarded Message 
Subject: Copyright in LGPL projects
Date: Mon, 4 Mar 2024 11:10:58 +0530
From: Alan M Varghese 
To: 1065...@bugs.debian.org
CC: Matthias Geiger , SmartList


Hello Mentors,

I have been working on packaging Hyprland window manager.
hyprlang[0] (with a 'g') is a new dependency for this project. This project
(hyprlang) is licensed under LGPL.

But, the project authors haven't included a copyright notice anywhere in the
project. It turns out that the authors are not sure if this is required for
an LGPL project[1].

  From a Debian perspective, what is the recommendation regarding this? Do we
require projects to include the copyright information along with LGPL?

If the copyright *has* to be included, is it enough to include it in a
COPYRIGHT file? I couldn't find an example of a project that does this. Most
projects seem to include a copyright line along with a short form of LGPL in
each file. (I think it may be more appealing to upstream authors if we don't
have to include the copyright in every file).

For example, libplacebo[2] is a library I found installed on my system that
uses LGPL. This project does not have a common copyright file, but there are
copyright notices in some source files[3]. While some other source files in
this project do not have a copyright notice[4][5][6].

Note: my doubts are specifically regarding the LGPL license. For other
licenses like BSD, I see both practices of including a COPYRIGHT file as well
as a short copyright notice in each file, or a combination of the two.

Thanks,
Alan M Varghese

[0] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1065352
[1] https://github.com/hyprwm/hyprlang/issues/28
[2] https://code.videolan.org/videolan/libplacebo
[3]
https://code.videolan.org/videolan/libplacebo/-/blob/master/src/dither.c?

ref_

type=heads [4]
https://code.videolan.org/videolan/libplacebo/-/blob/master/src/dummy.c?

ref_t

ype=heads [5]
https://code.videolan.org/videolan/libplacebo/-/blob/master/src/cache.c?

ref_t

ype=heads [6]
https://code.videolan.org/videolan/libplacebo/-/blob/master/src/

colorspace.c?

ref_type=heads







Re: FWD: Copyright in LGPL projects

2024-03-04 Thread Soren Stoutner
Alan,

These are good questions.

1.  Yes, there must be a copyright statement.  Only the person, people, group, 
or organization that holds the copyright can issue a license for other people 
to use the work.  So, you must have someone claiming a copyright or they do 
not have the legal ability to release the work to others under the LGPL.

2.  No, it is not required that each individual file contain a copyright 
statement or the header of the LGPL at the top.  The FSF recommends such as a 
best practice, and I would agree that it is desirable, but it is not required.

My recommendation would be that you communicate to the upstream project that 
they need to include the copyright and licensing information in the root of 
their repository, preferably all in one file, as a minimum requirement for you 
to be willing to package their project in Debian.

Soren

On Sunday, March 3, 2024 11:06:30 PM MST Alan M Varghese wrote:
> Sent message incorrectly to debian-mentors-request instead of debian-
mentors.
> Correcting.
> 
> 
>  Forwarded Message 
> Subject: Copyright in LGPL projects
> Date: Mon, 4 Mar 2024 11:10:58 +0530
> From: Alan M Varghese 
> To: 1065...@bugs.debian.org
> CC: Matthias Geiger , SmartList
> 
> 
> Hello Mentors,
> 
> I have been working on packaging Hyprland window manager.
> hyprlang[0] (with a 'g') is a new dependency for this project. This project
> (hyprlang) is licensed under LGPL.
> 
> But, the project authors haven't included a copyright notice anywhere in the
> project. It turns out that the authors are not sure if this is required for
> an LGPL project[1].
> 
>  From a Debian perspective, what is the recommendation regarding this? Do we
> require projects to include the copyright information along with LGPL?
> 
> If the copyright *has* to be included, is it enough to include it in a
> COPYRIGHT file? I couldn't find an example of a project that does this. Most
> projects seem to include a copyright line along with a short form of LGPL in
> each file. (I think it may be more appealing to upstream authors if we don't
> have to include the copyright in every file).
> 
> For example, libplacebo[2] is a library I found installed on my system that
> uses LGPL. This project does not have a common copyright file, but there are
> copyright notices in some source files[3]. While some other source files in
> this project do not have a copyright notice[4][5][6].
> 
> Note: my doubts are specifically regarding the LGPL license. For other
> licenses like BSD, I see both practices of including a COPYRIGHT file as well
> as a short copyright notice in each file, or a combination of the two.
> 
> Thanks,
> Alan M Varghese
> 
> [0] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1065352
> [1] https://github.com/hyprwm/hyprlang/issues/28
> [2] https://code.videolan.org/videolan/libplacebo
> [3]
> https://code.videolan.org/videolan/libplacebo/-/blob/master/src/dither.c?
ref_
> type=heads [4]
> https://code.videolan.org/videolan/libplacebo/-/blob/master/src/dummy.c?
ref_t
> ype=heads [5]
> https://code.videolan.org/videolan/libplacebo/-/blob/master/src/cache.c?
ref_t
> ype=heads [6]
> https://code.videolan.org/videolan/libplacebo/-/blob/master/src/
colorspace.c?
> ref_type=heads


-- 
Soren Stoutner
so...@debian.org

signature.asc
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FWD: Copyright in LGPL projects

2024-03-03 Thread Alan M Varghese

Sent message incorrectly to debian-mentors-request instead of debian-mentors. 
Correcting.


 Forwarded Message 
Subject: Copyright in LGPL projects
Date: Mon, 4 Mar 2024 11:10:58 +0530
From: Alan M Varghese 
To: 1065...@bugs.debian.org
CC: Matthias Geiger , SmartList 


Hello Mentors,

I have been working on packaging Hyprland window manager.
hyprlang[0] (with a 'g') is a new dependency for this project. This project 
(hyprlang) is licensed under LGPL.

But, the project authors haven't included a copyright notice anywhere in the 
project. It turns out that the
authors are not sure if this is required for an LGPL project[1].

From a Debian perspective, what is the recommendation regarding this? Do we 
require projects to include the
copyright information along with LGPL?

If the copyright *has* to be included, is it enough to include it in a 
COPYRIGHT file? I couldn't find an
example of a project that does this. Most projects seem to include a copyright 
line along with a short form
of LGPL in each file. (I think it may be more appealing to upstream authors if 
we don't have to include the
copyright in every file).

For example, libplacebo[2] is a library I found installed on my system that 
uses LGPL. This project does not
have a common copyright file, but there are copyright notices in some source 
files[3]. While some other source
files in this project do not have a copyright notice[4][5][6].

Note: my doubts are specifically regarding the LGPL license. For other licenses 
like BSD, I see both practices
of including a COPYRIGHT file as well as a short copyright notice in each file, 
or a combination of the two.

Thanks,
Alan M Varghese

[0] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1065352
[1] https://github.com/hyprwm/hyprlang/issues/28
[2] https://code.videolan.org/videolan/libplacebo
[3] 
https://code.videolan.org/videolan/libplacebo/-/blob/master/src/dither.c?ref_type=heads
[4] 
https://code.videolan.org/videolan/libplacebo/-/blob/master/src/dummy.c?ref_type=heads
[5] 
https://code.videolan.org/videolan/libplacebo/-/blob/master/src/cache.c?ref_type=heads
[6] 
https://code.videolan.org/videolan/libplacebo/-/blob/master/src/colorspace.c?ref_type=heads