Build targets for on-seL4 and not-on-seL4

This allows us to build versions of the website
for running on seL4/LionsOS, and for running on a
more standard webserver.

The version for running on LionsOS adds a link
in the footer to a diagram
and a description and where to get the source.

`make build` builds in _site, `make on_seL4` builds
into _site_on_seL4, and includes any material protected
by an `if site.on_seL4` guard.  Currently that's only in the
template.

Signed-off-by: Peter Chubb <Peter.Chubb@unsw.edu.au>
Signed-off-by: Ivan Velickovic <i.velickovic@unsw.edu.au>
Signed-off-by: James Archer <j.archer@unsw.edu.au>

.gitignore

@@ -2,6 +2,7 @@
 *.swp
 _site
 _preview
+_site_on_seL4
 .sass-cache
 .jekyll-cache
 .jekyll-metadata

.reuse/dep5

@@ -21,6 +21,10 @@ Files: .ruby-version
 Copyright: 2024 seL4 Project a Series of LF Projects, LLC.
 License: BSD-2-Clause
 
+Files: Info/Website/webserver.svg
+Copyright: UNSW
+License: CC-BY-SA-4.0
+
 Files: _data/menu.json
        _includes/breadcrumbs.html
        _includes/menu.html

Info/Website/index.html

@@ -0,0 +1,53 @@
+---
+# Copyright 2020 seL4 Project a Series of LF Projects, LLC.
+# SPDX-License-Identifier: CC-BY-SA-4.0
+title: About this website
+---
+<h1>
+  About this website
+</h1>
+<div class="row">
+  <div class="col-sm-6 col-3">
+    <img style=
+	 "padding:10px; width:inherit; vertical-align: top; float:
+         left;" src="./webserver.svg" alt="Webserver architecture
+         diagram" class="img-responsive img-fluid">
+  </div>
+  <div class="col-sm-6 col-3">
+    <p>
+      This website runs on <a href="https://lionsos.org">LionsOS</a>,
+      an operating system for embedded systems.  LionsOS is in turn
+      based on
+      the <a href="https://github.com/seL4/microkit">Microkit</a>, a
+      framework that presents a small set of simple abstractions over
+      seL4, and
+      the <a href="https://trustworthy.systems/projects/drivers">sel4
+      Device Driver Framework</a>.
+    </p>
+    <p>
+      Source for the system is
+      in <a href="https://github.com/au-ts/lionsos">the LionsOS</a>
+      repository.
+    </p>
+    <p>
+      The hardware is
+      an <a href="https://www.hardkernel.com/shop/odroid-c4/">Odroid
+      C4</a>, a quad-core Cortex A55 running at 1.2GHz with 4G of DDR4
+      RAM and a Gigabit ethernet.  We are using only one of the cores.
+    </p>
+    <p>
+      For ease of update, the website content is stored on an NFS
+      server.  It is built from content
+      on <a href="https://github.com/seL4/website">github.com</a> and
+      deployed to the NFS server as updates are accepted into the
+      tree.
+    </p>
+    <p>
+      The MicroPython code that actually implements the webserver is
+      based on
+      the <a href="https://github.com/miguelgrinberg/microdot">Microdot</a>
+      framework.  It uses asychronous access to network and
+      filesystems.
+    </p>
+  </div>
+</div>

Makefile

@@ -6,7 +6,8 @@ SHELL := bash
 MAKEFLAGS += --warn-undefined-variables --no-builtin-rules
 .DELETE_ON_ERROR:
 .SUFFIXES:
-.PHONY: help build serve debug preview clean doctor checklinks update
+.PHONY: help build serve debug preview clean doctor checklinks update \
+	on_seL4
 
 help:
 	@echo -e "Usage: make <target>. Available seL4 website targets:\n\
@@ -40,6 +41,9 @@ preview: JEKYLL_ENV := development
 preview: SERVE_HOST := --config "_config.yml,_preview.yml" $(SERVE_HOST)
 preview: build
 
+on_seL4: SERVE_HOST := --config "_config.yml,_on_seL4.yml"
+on_seL4: build
+
 clean doctor:
 	@bundle exec jekyll $@
 	@rm -rf _preview/*

README.md

@@ -52,6 +52,14 @@ make serve
 for the production build and `make debug` for the development build. See `make
 help` for all options.
 
+There are two variants of the website to build.  When running on
+LionsOS and seL4 we include an additional footer with a link to pages
+describing the hardware and software architecture of the LionsOS
+webserver.  To build this variant, use
+```sh
+make on_seL4
+```
+and the site will be generated into `_site_on_seL4/`.
 ## Docker
 
 The directory `docker/` provides a docker file and some scripts to host

_config.yml

@@ -11,7 +11,6 @@ static_url: "https://sel4.systems"
 baseurl: "" # the subpath of your site, e.g. /blog
 git_repo: https://github.com/seL4/website
 github_username: seL4
-on_seL4: false
 
 collections:
   - "news-items"

_layouts/default.html

@@ -91,6 +91,12 @@
     <div class="row">
       <!-- for screens larger than mobiles -->
       <div class="col-xs-6 hidden-xs">
+{% if site.on_seL4 %}
+  <a href="/Info/Website/">About this web server</a>
+  Served by <a href="https://micropython.org/">MicroPython</a>
+on <a href="https://lionsos.org/"> LionsOS</a> on seL4.
+<br/>
+{% endif %}
         Copyright &copy; 2024 seL4 Project a Series of LF Projects, LLC.<br/>
         seL4 is a trademark of LF Projects, LLC.<br/>
         For trademark usage guidelines, privacy and cookie policies,
@@ -106,9 +112,6 @@
       </div>
     </div>
   </div>
-{% if site.on_seL4 %}
-  Served by Apache on Linux on seL4.
-{% endif %}
 </footer> <!-- footer -->
 <!-- wrapper -->
 <script src={{ "/js/jquery.min.js" | relative_url }}></script>

_on_seL4.yml

@@ -0,0 +1,8 @@
+# Copyright 2024 seL4 Project a Series of LF Projects, LLC.
+# SPDX-License-Identifier: BSD-2-Clause
+##
+
+url: "https://beta.sel4.systems"
+static_url: "https://beta.sel4.systems"
+on_seL4: true
+destination: _site_on_seL4