[bug#41637] gnu: Add hashcash.

* gnu/packages/networking.scm (hashcash): New variable.
---

Is the license field here alright? Here's what the LICENSE file has to
say:

> This software can be distributed and used under any of the following
> licenses:
> 
> 	CPL
> 	public domain
> 	BSD (3 clause -- no advertising clause)
> 	LGPL (2.1)
> 	GPL (2)
> 
> in rough order of author preference.
> 
> The CPL is probably unique to this package, and is described here:
> http://www.cypherspace.org/CPL/; if you can't be bothered to figure it
> out feel free to use one of the other licenses.  Earlier versions
> where distributed just under CPL.  CPL allows you to re-license under
> a license of your choice, I just include other specific licenses to
> save people having to read, understand and feel confident in the
> validity of the CPL.
> 
> NOTE: on systems without a POSIX getopt this package will be linked
> with the included getopt.c which is distributed under GPL 2.

 gnu/packages/networking.scm | 46 +++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

+    (license license:public-domain)))

Hello Jakub,

> +     `(#:make-flags '("CC=gcc")

It would be better to use "cc-for-target" here. You can check if
cross-compilation works by running something like:

--8<---------------cut here---------------start------------->8---
guix build --target=aarch64-linux-gnu hashcash
--8<---------------cut here---------------end--------------->8---

Thanks,

Mathieu

On Tue, Jun 02, 2020 at 02:12:05PM +0200, Mathieu Othacehe wrote:
> 
> Hello Jakub,
> 
> > +     `(#:make-flags '("CC=gcc")
> 
> It would be better to use "cc-for-target" here. You can check if
> cross-compilation works by running something like:
> 
> --8<---------------cut here---------------start------------->8---
> guix build --target=aarch64-linux-gnu hashcash
> --8<---------------cut here---------------end--------------->8---

Thanks! I had no idea this affects cross-compilation... I have changed
that line to be

     `(#:make-flags (list (string-append "CC=" ,(cc-for-target)))

instead. Does the rest of the patch look alright?

Regards,
Jakub Kądziołka

Hey Jakub,

Thanks for fixing the cross-compilation, a full review this time :)

> +             (let* ((outdir (assoc-ref outputs "out"))
> +                    (bindir (string-append outdir "/bin"))
> +                    (mandir (string-append outdir "/share/man/man1"))
> +                    (docdir (string-append outdir "/share/doc/hashcash-" ,version)))
> +               ;; make install assumes /usr and doesn't provide a way to override it
> +               (install-file "hashcash" bindir)
> +               (install-file "hashcash.1" mandir)
> +               (install-file "README" docdir)
> +               (install-file "LICENSE" docdir)
> +               (install-file "CHANGELOG" docdir)

I think you can set the variables INSTALL_PATH, MAN_INSTALL_PATH and
DOC_INSTALL_PATH instead.

> +               #t))))))
> +    (home-page "https://www.hashcash.org/")
> +    (synopsis "Denial-of-service countermeasure")
> +    (description "Hashcash is a proof-of-work algorithm, which has been used
> +as a denial-of-service countermeasure technique in a number of systems.

You can remove "in a number of systems".

> +A hashcash stamp constitutes a proof-of-work which takes a parametrizable
> +amount of work to compute for the sender.  The recipient can verify received
> +hashcash stamps efficiently.
> +
> +This package contains a command-line tool for computing and verifying hashcash
> +stamps.")
> +    (license license:public-domain)))

I'm also concerned by this line in the Makefile:

--8<---------------cut here---------------start------------->8---
# request static link of -lcrypto only
LIBCRYPTO=/usr/lib/libcrypto.a
--8<---------------cut here---------------end--------------->8---

We should maybe add "openssl" to the inputs and fix this variable
(that's what Nix does).

Thanks,

Mathieu

On Wed, Jun 03, 2020 at 08:55:39AM +0200, Mathieu Othacehe wrote:
> 
> Hey Jakub,
> 
> Thanks for fixing the cross-compilation, a full review this time :)
> 
> > +             (let* ((outdir (assoc-ref outputs "out"))
> > +                    (bindir (string-append outdir "/bin"))
> > +                    (mandir (string-append outdir "/share/man/man1"))
> > +                    (docdir (string-append outdir "/share/doc/hashcash-" ,version)))
> > +               ;; make install assumes /usr and doesn't provide a way to override it
> > +               (install-file "hashcash" bindir)
> > +               (install-file "hashcash.1" mandir)
> > +               (install-file "README" docdir)
> > +               (install-file "LICENSE" docdir)
> > +               (install-file "CHANGELOG" docdir)
> 
> I think you can set the variables INSTALL_PATH, MAN_INSTALL_PATH and
> DOC_INSTALL_PATH instead.

Unfortunately, the variables are defined with `=` instead of `?=`, so
the Makefile always overwrites them. We would also want to skip
installing the `sha1' tool like Debian does, since `sha1sum' is already
a thing.

> > +               #t))))))
> > +    (home-page "https://www.hashcash.org/")
> > +    (synopsis "Denial-of-service countermeasure")
> > +    (description "Hashcash is a proof-of-work algorithm, which has been used
> > +as a denial-of-service countermeasure technique in a number of systems.
> 
> You can remove "in a number of systems".
> 
> > +A hashcash stamp constitutes a proof-of-work which takes a parametrizable
> > +amount of work to compute for the sender.  The recipient can verify received
> > +hashcash stamps efficiently.
> > +
> > +This package contains a command-line tool for computing and verifying hashcash
> > +stamps.")
> > +    (license license:public-domain)))
> 
> I'm also concerned by this line in the Makefile:
> 
> --8<---------------cut here---------------start------------->8---
> # request static link of -lcrypto only
> LIBCRYPTO=/usr/lib/libcrypto.a
> --8<---------------cut here---------------end--------------->8---
> 
> We should maybe add "openssl" to the inputs and fix this variable
> (that's what Nix does).

From what I've read, openssl is not used by default, but only when a
target like `gnu-openssl' is used. I'll make a build with openssl and
benchmark which is faster...

Regards,
Jakub Kądziołka

>> I think you can set the variables INSTALL_PATH, MAN_INSTALL_PATH and
>> DOC_INSTALL_PATH instead.
>
> Unfortunately, the variables are defined with `=` instead of `?=`, so
> the Makefile always overwrites them. We would also want to skip
> installing the `sha1' tool like Debian does, since `sha1sum' is already
> a thing.

Not if they are passed on the command line, see:
https://www.gnu.org/software/make/manual/html_node/Overriding.html

Mathieu

Pushed to master as commit ef6d3b643689953b71fe103e8c6f520b54996f11, closing.