LibCompress: Implement Brotli decompressor

This implements the BrotliDecompressionStream, which is a Core::Stream
that can decompress another Core::Stream.

21 files changed, 943 insertions, 0 deletions

diff --git a/Tests/LibCompress/CMakeLists.txt b/Tests/LibCompress/CMakeLists.txt
index 4569090371..8e35e7985f 100644
--- a/Tests/LibCompress/CMakeLists.txt
+++ b/Tests/LibCompress/CMakeLists.txt
@@ -1,4 +1,5 @@
 set(TEST_SOURCES
+    TestBrotli.cpp
     TestDeflate.cpp
     TestGzip.cpp
     TestZlib.cpp
@@ -7,3 +8,5 @@ set(TEST_SOURCES
 foreach(source IN LISTS TEST_SOURCES)
     serenity_test("${source}" LibCompress LIBS LibCompress)
 endforeach()
+
+install(DIRECTORY brotli-test-files DESTINATION usr/Tests/LibCompress)
diff --git a/Tests/LibCompress/TestBrotli.cpp b/Tests/LibCompress/TestBrotli.cpp
new file mode 100644
index 0000000000..447df841c8
--- /dev/null
+++ b/Tests/LibCompress/TestBrotli.cpp
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2022, Michiel Visser <opensource@webmichiel.nl>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibTest/TestCase.h>
+
+#include <LibCompress/Brotli.h>
+#include <LibCore/Stream.h>
+
+static void run_test(StringView const file_name)
+{
+    // This makes sure that the tests will run both on target and in Lagom.
+#ifdef __serenity__
+    String path = String::formatted("/usr/Tests/LibCompress/brotli-test-files/{}", file_name);
+#else
+    String path = String::formatted("brotli-test-files/{}", file_name);
+#endif
+
+    auto cmp_file = MUST(Core::Stream::File::open(path, Core::Stream::OpenMode::Read));
+    auto cmp_data = MUST(cmp_file->read_all());
+
+    String path_compressed = String::formatted("{}.br", path);
+
+    auto file = MUST(Core::Stream::File::open(path_compressed, Core::Stream::OpenMode::Read));
+    auto brotli_stream = Compress::BrotliDecompressionStream { *file };
+    auto data = MUST(brotli_stream.read_all());
+
+    EXPECT_EQ(data, cmp_data);
+}
+
+TEST_CASE(brotli_decompress_uncompressed)
+{
+    run_test("wellhello.txt");
+}
+
+TEST_CASE(brotli_decompress_simple)
+{
+    run_test("hello.txt");
+}
+
+TEST_CASE(brotli_decompress_simple2)
+{
+    run_test("wellhello2.txt");
+}
+
+TEST_CASE(brotli_decompress_lorem)
+{
+    run_test("lorem.txt");
+}
+
+TEST_CASE(brotli_decompress_lorem2)
+{
+    run_test("lorem2.txt");
+}
+
+TEST_CASE(brotli_decompress_transform)
+{
+    run_test("transform.txt");
+}
+
+TEST_CASE(brotli_decompress_serenityos_html)
+{
+    run_test("serenityos.html");
+}
+
+TEST_CASE(brotli_decompress_happy3rd_html)
+{
+    run_test("happy3rd.html");
+}
+
+TEST_CASE(brotli_decompress_katica_regular_10_font)
+{
+    run_test("KaticaRegular10.font");
+}
+
+TEST_CASE(brotli_decompress_zero_one_bin)
+{
+    // This makes sure that the tests will run both on target and in Lagom.
+#ifdef __serenity__
+    String path = "/usr/Tests/LibCompress/brotli-test-files/zero-one.bin";
+#else
+    String path = "brotli-test-files/zero-one.bin";
+#endif
+
+    String path_compressed = String::formatted("{}.br", path);
+
+    auto file = MUST(Core::Stream::File::open(path_compressed, Core::Stream::OpenMode::Read));
+    auto brotli_stream = Compress::BrotliDecompressionStream { *file };
+
+    u8 buffer_raw[4096];
+    Bytes buffer { buffer_raw, 4096 };
+
+    size_t bytes_read = 0;
+    while (true) {
+        size_t nread = MUST(brotli_stream.read(buffer)).size();
+        if (nread == 0)
+            break;
+
+        for (size_t i = 0; i < nread; i++) {
+            if (bytes_read < 16 * MiB)
+                EXPECT(buffer[i] == 0);
+            else
+                EXPECT(buffer[i] == 1);
+        }
+
+        bytes_read += nread;
+    }
+    EXPECT(bytes_read == 32 * MiB);
+    EXPECT(brotli_stream.is_eof());
+}
diff --git a/Tests/LibCompress/brotli-test-files/KaticaRegular10.font b/Tests/LibCompress/brotli-test-files/KaticaRegular10.font
new file mode 100644
index 0000000000..4c19ad065b
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/KaticaRegular10.font
diff --git a/Tests/LibCompress/brotli-test-files/KaticaRegular10.font.br b/Tests/LibCompress/brotli-test-files/KaticaRegular10.font.br
new file mode 100644
index 0000000000..df58600268
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/KaticaRegular10.font.br
diff --git a/Tests/LibCompress/brotli-test-files/happy3rd.html b/Tests/LibCompress/brotli-test-files/happy3rd.html
new file mode 100644
index 0000000000..4648fb52fc
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/happy3rd.html
@@ -0,0 +1,628 @@
+<!DOCTYPE html>
+<html>
+    <head>
+        <title>SerenityOS: Year 3 in review</title>
+        <style>
+            body {
+                margin-left: auto;
+                margin-right: auto;
+                width: 600px;
+                font-size: 12pt;
+                font-family: sans-serif;
+            }
+            @media screen and (max-width: 610px) {
+                header h1 {
+                    margin: 0;
+                }
+                body {
+                    margin-top: none;
+                    width: 100%;
+                }
+                #intro, footer {
+                    margin-left: 1em;
+                    margin-right: 1em;
+                }
+            }
+            @media screen and (min-width: 610px) {
+                article, h1, h2 {
+                    border-radius: 10px;
+                }
+            }
+
+            @media only screen and (min-device-width: 375px) and (max-device-width: 667px) and (-webkit-min-device-pixel-ratio: 2) {
+                body {
+                    width: 90%;
+                    font-size: 1.4em;
+                }
+                
+            }
+
+            h1, h2 {
+                padding: 12px;
+                background: #000;
+                color: white;
+            }
+            article h1 {
+                font-size: 1.1em;
+                vertical-align: middle;
+                margin: 0;
+            }
+            article h1 :link,
+            article h1 :visited {
+                color: white;
+            }
+            article img,
+            article iframe {
+                max-width: 100%;
+                border: 1px solid black;
+            }
+            article img.avatar {
+                width: 64px;
+                float: right;
+                border: none;
+                margin-bottom: 8px;
+            }
+            article {
+                padding: 20px;
+                margin-bottom: 20px;
+                background: #ddd;
+            }
+            article.developer {
+                background: #ddf;
+                font-style: italic;
+            }
+            article iframe {
+                border: 1px solid black;
+            }
+            article.hax0r {
+                background: black;
+                font-family: monaco;
+            }
+            article.hax0r,
+            article.hax0r h1,
+            article.hax0r :link,
+            article.hax0r :visited {
+                color: lime;
+            }
+            article.hax0r h1 {
+                background: #040;
+            }
+            .yakstack {
+                height: 96px;
+                margin-left: 32px;
+                float: right;
+            }
+        </style>
+    </head>
+    <body>
+        <header>
+            <h1>SerenityOS: Year 3 in review</h1>
+        </header>
+        <main>
+            <div id="intro">
+            <img class="yakstack" src="yakstack.png">
+
+            <p><b>Hello friends! :^)</b>
+
+            <p>Today we celebrate the third birthday of SerenityOS, counting from the first commit in the
+            <a href="https://github.com/SerenityOS/serenity/">git repository</a>, on October 10, 2018.
+
+            <p>Previous birthdays: <a href="https://serenityos.org/happy/1st">1st</a>, <a href="https://serenityos.org/happy/2nd">2nd</a>.
+
+            <p>What follows is a list of interesting events from the past year, mixed with random development
+            screenshots and also reflections from other developers in the SerenityOS community.
+            </div>
+
+            <article>
+		<h1>Introduction to SerenityOS</h1>
+
+                <p>SerenityOS is a from-scratch desktop operating system that combines a Unix-like core
+                with the look&amp;feel of 1990s productivity software. It's written in modern C++ and
+                goes all the way from kernel to web browser. The project aims to build everything in-house
+                instead of relying on third-party libraries.
+
+                <p>I started building this system after
+        	<a href="https://www.youtube.com/watch?v=j3JkNGKZtqM">finishing a 3-month rehabilitation program for drug addiction</a>
+                in 2018. I found myself with a lot of time and nothing to spend it on. So I began
+                building something I'd always wanted to build: my very own dream OS.
+
+                <p>Parts of my development work is presented in screencast format on 
+        	<a href="https://youtube.com/andreaskling">my YouTube channel</a>.
+                I also post monthly update videos showcasing new features there.
+            </article>
+
+            <article>
+                <h1>2020-12-06: Working on Reddit support in LibWeb</h1>
+
+                <p>Building a browser takes time, and there's a lot of unglamorous
+                work like figuring out why things don't align right. Fortunately it's
+                also really fun!
+
+                <p><img src="2020-12-06.png">
+            </article>
+
+            <article>
+                <h1>2020-12-20: Interview on CppCast</h1>
+
+                <p>I went on the <a href="https://cppcast.com">CppCast</a> podcast with <a href="https://twitter.com/lefticus">Jason Turner</a>
+                and <a href="https://twitter.com/robwirving">Rob Irving</a> to talk about SerenityOS.
+
+                <p>It was my first time doing an interview and I was really nervous about it,
+                but it turned out very okay!
+
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/SRq9HSGn2qE" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+            </article>
+
+            <article class="hax0r">
+                <h1>2020-12-20: The 2020 HXP CTF</h1>
+                <p>
+                SerenityOS was once again featured in the <a href="https://ctf.link/">HXP CTF</a>.
+                After being in their 2019 CTF, we spent a whole bunch of time beefing up system security,
+                and it definitely helped: This time, only 1 team was able to find an exploit,
+                compared to 6 teams in the previous CTF!
+                <p>
+                Write-ups &amp; exploits from the event:
+                <ul>
+                    <li><a href="https://hxp.io/blog/79/hxp-CTF-2020-wisdom2/"><b>yyyyyyy</b> found a kernel LPE due to a race condition between execve() and ptrace()</a></li>
+                    <li><a href="https://github.com/allesctf/writeups/blob/master/2020/hxpctf/wisdom2/writeup.md"><b>ALLES! CTF</b> found a kernel LPE due to missing EFLAGS validation in ptrace().</a></li>
+                </ul>
+            </article>
+
+            <article>
+                <h1>2021-01-06: Reading "Hackles" on SerenityOS</h1>
+
+                <p>I was very happy to get the classic Unix geek webcomic
+                <a href="http://hackles.org">Hackles</a> working in Browser.
+
+                <p><img src="2021-01-06.png">
+            </article>
+
+            <article>
+                <h1>2021-01-10: LiveOverflow videos about SerenityOS</h1>
+                <p>At the start of 2021, hacking YouTuber LiveOverflow published
+                a series of videos about SerenityOS, looking into exploits against
+                the system.
+                
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/qUh507Na9nk" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+                <p>All SerenityOS related videos from LiveOverflow:
+                <ul>
+                    <li><a href="https://youtube.com/watch?v=qUh507Na9nk">Kernel Root Exploit via a ptrace() and execve() Race Condition</a></li>
+                    <li><a href="https://youtube.com/watch?v=oIAP1_NrSbY">Reading Kernel Source Code - Analysis of an Exploit</a></li>
+                    <li><a href="https://youtube.com/watch?v=1hpqiWKFGQs">How CPUs Access Hardware - Another SerenityOS Exploit</a></li>
+                </ul>
+            </article>
+
+            <article class="hax0r">
+                <h1>2021-02-11: vakzz's full chain exploit</h1>
+                <p><a href="https://twitter.com/wcbowling">William Bowling (vakzz)</a> released
+                the first ever full chain exploit for SerenityOS, combining a browser bug and
+                a kernel bug to get remote root access via opening a web page!
+
+                <p>Check out vakzz's <a href="https://devcraft.io/2021/02/11/serenityos-writing-a-full-chain-exploit.html">excellent write-up</a>
+                for a step-by-step walthrough.
+
+            </article>
+
+            <article>
+                <h1>2021-02-13: SerenityOS developer interview: Linus Groh</h1>
+
+                <p>I wanted to introduce my YouTube audience to more of the SerenityOS
+                developer community, and Linus became the first guest in my developer
+                interview series!
+
+                <p>It was really nice to shine a light on someone else doing great work on the project.
+
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/oG8RSX1hyCg" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+            </article>
+
+            <article class="developer">
+                <h1>
+                    Developer reflections: <a href="https://twitter.com/linusgroh">Linus Groh</a>
+                    <img class="avatar nolinkify" src="linusg.png">
+                </h1>
+
+                <p>One of my favorite aspects of the past year of SerenityOS development
+                is the overall progress on the browser! There's still a ton of work to
+                do, but we're starting to get more and more websites into a recognizable
+                shape - compared to a year ago, the number of blank pages and crashes
+                on load is reduced considerably.
+
+                <p>It's also one of the most collaborative subsystems: everything from
+                improving spec compliance in our JavaScript engine and adding some
+                basic optimizations to implementing countless Web APIs, and continuous
+                work on CSS and DOM has been a team effort. It's great to see everyone
+                get comfortable, explore, and eventually become experts in their
+                favorite topics of browser and JS engine development!
+
+                <p>It's been so much fun building all these things together, and I'm
+                excited to see how far we can get in another year :^)
+            </article>
+
+
+            <article>
+                <h1>2021-03-06: Classic game "port": Diablo</h1>
+
+                <p>DevilutionX is a reverse engineered "port" of the classic game Diablo.
+                I ported it to SerenityOS and captured the process in a video.
+                To date, this is my most viewed video and thousands of people discovered
+                the project through this video.
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/ZOzZ8R4gphE" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+
+                <p>I also finally beat the game!
+
+                <p><img src="2021-03-06.png">
+            </article>
+
+            <article>
+                <h1>2021-04-01: A new direction for the project</h1> 
+
+                <p>On April 1st, I posted a video announcing a new visual and spiritual direction
+                for the SerenityOS project. Most people got the joke :^)
+
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/a-WXzLKv_rc" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+            </article>
+
+            <article>
+                <h1>
+                    2021-04-10: Opening a SerenityOS Discord server
+                    <img class="avatar nolinkify" src="yakbait.png">
+                </h1>
+
+                <p>We decided to try out Discord after seeing how it was used to great effect
+                in the <a href="https://ziglang.org">Zig language</a> community.
+
+                <p>It's been a huge success! While our IRC channel peaked at about 170 users,
+                we've got well over 4000 members on Discord, and it's helped us reach new
+                levels of collaboration that were simply not possible with IRC.
+
+                <p>It has also spawned an extremely nerdy culture of <a href="https://github.com/kleinesfilmroellchen/yaksplained">yak-related memes</a>.
+
+                <p><img src="2021-04-10.png">
+            </article>
+
+            <article>
+                <h1>2021-04-18: Interviewed on "Systems with JT"</h1>
+
+                <p>Programming language wizard <a href="https://twitter.com/jntrnr">JT</a> invited me for an live interview
+                about SerenityOS and everything around it. It was my first live interview, and I was kinda nervous
+                but I think it went well!
+
+                <p>JT also did a <a href="https://www.youtube.com/watch?v=TtV86uL5oD4">heartwarming video review</a> of SerenityOS back around Christmas.
+
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/5h8bo9OxCwI" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+            </article>
+
+            <article>
+                <h1>2021-04-26: More project maintainers</h1>
+
+                <p>In the interview with JT, one of the things that came up was my own
+                scalability as a project maintainer. Up until this point I had been doing
+                all the PR review and merging myself.
+
+                <p>After talking about it with JT, I realized that I needed to ask for
+                some help from a handful of trusted contributors. It was scary to give up
+                a bit of control, but in retrospect it's one of the best decisions I've made. :^)
+
+                <p>At the time of writing, we now have five maintainers in addition to myself (in alphabetical order):
+                <ul>
+                    <li><a href="https://twitter.com/the_semicolon_">Ali Mohammadpur</a></li>
+                    <li><a href="https://twitter.com/bgianf">Brian Gianforcaro</a></li>
+                    <li><a href="https://twitter.com/gunnarbeutner">Gunnar Beutner</a></li>
+                    <li><a href="https://twitter.com/horowitz_idan">Idan Horowitz</a></li>
+                    <li><a href="https://twitter.com/linusgroh">Linus Groh</a></li>
+                </ul>
+
+                <p>They each bring their own expertise and passion to the project, and they've been doing a great job
+                at keeping the project moving forward while growing.
+            </article>
+
+            <article>
+                <h1>2021-05-16: Some GUI face-lifts</h1>
+
+                <p>Sometimes I like to pick out a part of the GUI that is particularly weak
+                and spend some time on improving it. Here I was working on the PixelPaint
+                application, and also the system shutdown dialog.
+
+                <p><img src="2021-05-16.png">
+                <p><img src="2021-05-16-2.png">
+            </article>
+
+            <article>
+                <h1>2021-05-27: Linus gets on GitHub Sponsors</h1>
+
+                <p>Linus becomes the second person to accept <a href="https://github.com/sponsors/linusg">sponsorships</a>
+                for his SerenityOS work. More people getting sponsored to work on SerenityOS is super cool!
+            </article>
+
+            <article>
+                <h1>2021-05-28: I quit my job to work on SerenityOS full time!</h1>
+                <p>As of May of 2021, I'm receiving enough in donations to be able to support
+                myself while working full-time on SerenityOS!
+
+                I wrote a <a href="https://awesomekling.github.io/I-quit-my-job-to-focus-on-SerenityOS-full-time/">blog post about it here</a> and people were very
+                <a href="https://www.osnews.com/story/133492/serenityos-founder-and-main-developer-goes-full-time-for-serenityos/">supportive</a>
+                <a href="https://news.ycombinator.com/item?id=27317655">around</a>
+                <a href="https://www.reddit.com/r/SerenityOS/comments/nn1id7/i_quit_my_job_to_focus_on_serenityos_full_time/">the</a>
+                <a href="https://lobste.rs/s/lsumm4/i_quit_my_job_focus_on_serenityos_full_time">web</a>.
+
+                <p>I'm extremely grateful for all the support, and it's super exciting to be
+                able to focus on this full time! Massive thanks to everyone who has supported
+                me over the years! If you would like to help me out as well, check out
+                the links at the bottom of this page.
+            </article>
+
+            <article>
+                <h1>2021-06-12: Interview on Zig SHOWTIME!</h1>
+
+                <p>I was a guest on the <a href="https://zig.show/">Zig SHOWTIME</a> variety show
+                from the <a href="https://ziglang.org">Zig language</a> community. The theme was
+                "tech, taste and soul" and the interview lasted almost 3 hours. Exhausting but fun!
+
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/e_hCJI__q_4" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+            </article>
+
+            <article>
+                <h1>2021-06-30: 64-bit mode activated!</h1>
+
+                <p>Up until this point, SerenityOS was a 32-bit x86-only system. Then came x86_64,
+                much thanks to the hard work of <a href="https://twitter.com/gunnarbeutner">Gunnar Beutner</a>
+                who decided that the port was <i>going to happen</i>, and then didn't stop until it was up and running!
+
+                <p><img src="x86_64.png">
+            </article>
+
+            <article class="developer">
+                <h1>
+                    Developer reflections: <a href="https://twitter.com/bgianf">Brian Gianforcaro</a>
+                    <img class="avatar nolinkify" src="bgianf.jpg">
+                </h1>
+
+                <p>The past year of Serenity development has been super exciting! One of my favorite things
+                to happen was the bring up of the x86_64 Kernel. Andreas started making baby steps in Feb 2021,
+                followed by others contributing additional fixes, until around Jun 2021 when
+                <a href="https://twitter.com/gunnarbeutner">Gunnar Beutner</a> started contributing tons
+                of patches and with the help of many others got the system booting and running on x86_64.
+                In my mind this was a significant symbolic step for the project and the community, onboarding
+                another architecture makes the system a bit more real in my mind.
+
+                <p>From the community perspective I found it very inspiring how Gunnar just took the lead and
+                started fixing issues left and right. The community saw the momentum and started working
+                on fixes as well, and everyone together got the system running.
+
+                <p>I wish Andreas, the SerenityOS project and community, continued success and here's hoping
+                for another fruitful year of fun and progress. With the
+                <a href="https://github.com/SerenityOS/serenity/pull/10276">nascent aarch64 port</a> under way by 
+                <a href="https://twitter.com/thakis">Nico Weber</a>, and the countless other exciting things
+                folks are working on, I'm excited to see what the next year has in store! :^)
+            </article>
+
+
+            <article>
+                <h1>2021-07-08: SerenityOS Office Hours</h1>
+
+                <p>After an interesting back &amp; forth "discussion" with my YouTube audience
+                that started with the question "Am I losing touch with the audience?",
+                I decided to put some serious effort into connecting with the audience.
+
+                <p>After some experimentation, I finally arrived at the <b>SerenityOS Office Hours</b>
+                format. This is a weekly Q&amp;A livestream that I do every Friday at 4pm Swedish Time.
+                People are invited to ask any technical or non-technical question about SerenityOS
+                and we dig into whatever topics come up. It has been well-received and I've really
+                enjoyed being able to answer questions interactively!
+
+                <p>Check out my <a href="https://www.youtube.com/playlist?list=PLMOpZvQB55bf4FjluKyo01ZnXq75SaU5L">stream archive</a>
+                on YouTube. (And come say hi when I'm live some time!)
+
+            </article>
+
+            <article>
+                <h1>2021-07-08: A world map of SerenityOS hackers</h1>
+
+                <p>Linus created a <a href="https://usermap.serenityos.org/">collaborative map</a>
+                of SerenityOS developers &amp; users around the world.
+
+                <p><a href="https://usermap.serenityos.org"><img src="usermap.png"></a>
+            </article>
+
+            <article>
+                <h1>2021-07-20: TrueType renderer improvements</h1>
+
+                <p>While I'm a big fan of bitmap fonts personally, I did spend some time working
+                on our TrueType renderer, fixing up things like vertical alignment and glyph sizes.
+
+                <p>I also did some work to support the <b style="font-family: Tahoma, sans-serif">Microsoft Tahoma</b>
+                and <b style="font-family: 'JetBrains Mono', sans-serif">JetBrains Mono</b> typefaces,
+                seen in this screenshot!
+
+                <p><img src="2021-07-20.png">
+            </article>
+
+            <article>
+                <h1>2021-07-26: Building a "Settings" app</h1>
+
+                <p>Until this point, all the various settings dialogs were scattered
+                around the system menu. I decided it was time to collect them in a
+                simple Settings application instead. I think it turned out quite nice!
+
+                <p><img src="2021-07-26.png">
+            </article>
+
+            <article>
+                <h1>2021-07-26: SerenityOS developer interview: Ali Mohammadpur</h1>
+
+                <p>I did another developer interview video! This time with Ali,
+                who is behind many of the subsystems in Serenity (including TLS,
+                line editing, the spreadsheet, and more!)
+
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/BL5h6XEIusQ" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+            </article>
+
+            <article>
+                <h1>2021-08-10: Working on multi-core stability</h1>
+
+                <p>Multi-core support is still immature in SerenityOS, but we have been making some
+                strides forward in this area. In this screenshot, I'm successfully running <b>Quake II</b>
+                using 2 CPU's simultaneously.
+
+                <p><img src="2021-08-10.png">
+            </article>
+
+            <article>
+                <h1>2021-08-18: ArsTechnica reviews SerenityOS</h1>
+                <p>In mid-August, ArsTechnica ran a <a href="https://arstechnica.com/gadgets/2021/08/not-a-linux-distro-review-serenityos-is-a-unix-y-love-letter-to-the-90s/">feature article on SerenityOS</a>.
+                This came out of nowhere and was a lot of fun!
+                <p><a href="https://arstechnica.com/gadgets/2021/08/not-a-linux-distro-review-serenityos-is-a-unix-y-love-letter-to-the-90s/"><img class="nolinkify" src="arstechnica.png"></a>
+            </article>
+
+            <article>
+                <h1>2021-08-29: Showing SerenityOS to my nephew</h1>
+
+                <p>My nephew called me on Skype while I was hacking on something, and I asked
+                if he wanted a tour of the operating system. He said yes, and I got this sweet
+                screenshot of him excitedly seeing me beat our Breakout game!
+
+                <p><img src="2021-08-29.png">
+            </article>
+
+            <article>
+                <h1>2021-09-12: 500 contributors on GitHub!</h1>
+
+                <p>It's wild how many people have <a href="https://github.com/SerenityOS/serenity/graphs/contributors">contributed</a>
+                to the project at this point!
+
+                <p><img src="2021-09-12.png">
+            </article>
+
+            <article>
+                <h1>2021-09-18: Linus Groh interviewed on CppCast</h1>
+
+                <p>It's been so cool to see <a href="https://linus.dev/posts/my-journey-with-serenityos/">Linus's journey with SerenityOS</a>,
+                from not knowing C++ at all 18 months ago, to being interviewed on a major C++ podcast.
+
+                <center><iframe width="560" height="315" data-src="https://www.youtube.com/embed/YLN0A9hziKQ" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe></center>
+            </article>
+
+            <article>
+                <h1>2021-09-19: Reading the HTML spec</h1>
+
+                <p>It's a pretty cool milestone when your browser engine is strong enough
+                to download and display the HTML spec itself. 
+
+                <p><img src="2021-09-19.png">
+            </article>
+
+            <article class="developer">
+                <h1>
+                    Developer reflections: <a href="https://twitter.com/horowitz_idan">Idan Horowitz</a>
+                    <img class="avatar nolinkify" src="idanho.jpg">
+                </h1>
+
+                <p>One of the main subprojects in LibJS that was being worked on in 2021 was support for
+                the stage 3 <a href="https://github.com/tc39/proposal-temporal">Temporal proposal</a>,
+                which aims to replace the old and awkward <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date">Date API</a>
+                with a more modern, unified and fully-featured interface.
+
+                <p>As a result of the efforts of many contributors (with some of the most notable ones
+                being <a href="https://twitter.com/linusgroh">Linus Groh</a>
+                and <a href="https://github.com/Lubrsi">Luke Wilde</a>) Serenity's
+                LibJS contains the most fleshed out Temporal implementation out of all the popular Javascript engines.
+
+            </article>
+
+            <article>
+                <h1>2021-10-02: Browser performance work</h1>
+
+                <p>Lately I've been doing a ton of work on browser performance, trying to
+                bring it to a point where it can display complex pages in a somewhat reasonable
+                time.
+
+                <p>Here I am using Profiler to examine what appears to be memory allocation
+                performance in our regular expression engine.
+
+                <p>The profiling system has matured quite a bit during the last year. It now
+                has the ability to capture full-system profiles, and we've got more visualizations
+                to aid in performance analysis. :^)
+
+                <p><img src="2021-10-02.png">
+            </article>
+
+            <article>
+                <h1>Monthly update videos</h1>
+
+                <p>The tradition of the monthly SerenityOS update video is alive and well,
+                ever since my first-ever update video in March 2019.
+
+                <p>Something new this year is that for the last couple of videos, I've been
+                joined by Linus in the videos. The sheer amount of things happening month-to-month
+                was getting hard to cover by myself, and it's great to share the stage with
+                someone else who cares deeply about the project as well.
+
+                <p><ul>
+                    <li><a href="https://www.youtube.com/watch?v=L-IFGxw-kV4">SerenityOS update (October 2020)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=AYZ1Wqb9p2w">SerenityOS update (November 2020)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=7aof37-uCRE">SerenityOS update (December 2020)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=Arfy5iX0wgI">SerenityOS update (January 2021)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=M81Hy5UP2nA">SerenityOS update (February 2021)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=2OdYWoXIVd0">SerenityOS update (March 2021)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=KehSJ_fdTxU">SerenityOS update (April 2021)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=O3MtPgTUOC8">SerenityOS update (May 2021)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=QI3o2G8MPbQ">SerenityOS update (June 2021)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=nUCpt6F5q-s">SerenityOS update (July 2021)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=GT2SO-X2Wik">SerenityOS update (August 2021)</a></li>
+                    <li><a href="https://www.youtube.com/watch?v=y4bsO4E0G38">SerenityOS update (September 2021)</a></li>
+                </ul>
+
+                <p>Check out the <a href="https://www.youtube.com/playlist?list=PLMOpZvQB55bfp6ykOLayLqLrjcpv_Sw3P">playlist on YouTube</a>
+                for the full archive!
+            </article>
+        </main>
+
+        <footer>
+            <h2>Thanks</h2>
+
+            <p>To all the awesome people who have particpated in the last year, writing code,
+            bug reports, documentation, commenting/liking/sharing my videos, sending letters,
+            chilling on Discord, coming to the Office Hours livestreams, telling your friends,
+            etc, thank you all!
+
+            <p>I'm unbelievably grateful for all the love and support this project receives!
+
+            <p>And also, a huge <b>thank you!</b> to everyone who has supported me via
+            <a href="https://github.com/sponsors/awesomekling">GitHub Sponsors</a>,
+            <a href="https://patreon.com/serenityos">Patreon</a>,
+            and <a href="https://paypal.me/awesomekling">PayPal</a>. Thanks to you, I'm able
+            to do this full time and I'm excited to see where we can push this project!
+ 
+            <p>All right, let's keep moving forward into year number 4!
+
+            <p><i>Andreas Kling, 2021-10-10</i>
+            <br><a href="https://github.com/awesomekling">GitHub</a> |
+            <a href="https://youtube.com/c/AndreasKling">YouTube</a> |
+            <a href="https://twitter.com/awesomekling">Twitter</a> |
+            <a href="https://patreon.com/serenityos">Patreon</a> |
+            <a href="https://paypal.me/awesomekling">PayPal</a> |
+            <a href="https://store.serenityos.org">Store</a>
+
+            <br><br>
+        </footer>
+        <script>
+            // Don't insert YouTube iframes on serenity, since we can't play the videos yet anyway.
+            if (navigator.platform != "SerenityOS") {
+                for (let iframe of document.getElementsByTagName("iframe")) {
+                    iframe.setAttribute("src", iframe.getAttribute("data-src"));
+                }
+            }
+
+            // Linkify <img> elements without the 'nolinkify' class.
+            for (let img of document.querySelectorAll("article img:not(.nolinkify)")) {
+                let a = document.createElement("a");
+                a.href = img.src;
+                img.parentNode.replaceChild(a, img);
+                a.appendChild(img);
+            }
+
+            let stack = document.getElementsByClassName("yakstack")[0];
+            stack.onmousedown = function() { stack.src = "yakoverflow.png"; }
+        </script>
+    </body>
+</html>
diff --git a/Tests/LibCompress/brotli-test-files/happy3rd.html.br b/Tests/LibCompress/brotli-test-files/happy3rd.html.br
new file mode 100644
index 0000000000..f2e84ebbcc
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/happy3rd.html.br
diff --git a/Tests/LibCompress/brotli-test-files/hello.txt b/Tests/LibCompress/brotli-test-files/hello.txt
new file mode 100644
index 0000000000..4c02f53425
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/hello.txt
@@ -0,0 +1 @@
+Hello hello hello hello hello hello hello hello hello
diff --git a/Tests/LibCompress/brotli-test-files/hello.txt.br b/Tests/LibCompress/brotli-test-files/hello.txt.br
new file mode 100644
index 0000000000..fd9a51fdd1
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/hello.txt.br
diff --git a/Tests/LibCompress/brotli-test-files/lorem.txt b/Tests/LibCompress/brotli-test-files/lorem.txt
new file mode 100644
index 0000000000..81ec2ff1ef
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/lorem.txt
@@ -0,0 +1 @@
+Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Pharetra vel turpis nunc eget lorem. Gravida dictum fusce ut placerat orci nulla pellentesque. Potenti nullam ac tortor vitae purus faucibus ornare suspendisse. A lacus vestibulum sed arcu non odio. Ac odio tempor orci dapibus ultrices in iaculis nunc sed. In arcu cursus euismod quis. Pretium lectus quam id leo in. Ac ut consequat semper viverra nam libero justo laoreet sit. Ut porttitor leo a diam sollicitudin tempor. Libero volutpat sed cras ornare arcu dui vivamus. Eu scelerisque felis imperdiet proin fermentum leo. Ut pharetra sit amet aliquam id diam. Diam quis enim lobortis scelerisque fermentum dui. Pellentesque eu tincidunt tortor aliquam nulla facilisi cras. Rhoncus urna neque viverra justo nec ultrices dui.
diff --git a/Tests/LibCompress/brotli-test-files/lorem.txt.br b/Tests/LibCompress/brotli-test-files/lorem.txt.br
new file mode 100644
index 0000000000..29268b79c0
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/lorem.txt.br
diff --git a/Tests/LibCompress/brotli-test-files/lorem2.txt b/Tests/LibCompress/brotli-test-files/lorem2.txt
new file mode 100644
index 0000000000..c1677f4cd9
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/lorem2.txt
@@ -0,0 +1 @@
+nibh praesent tristique magna sit amet purus gravida quis blandit turpis cursus in hac habitasse platea dictumst quisque sagittis purus sit amet volutpat consequat mauris nunc congue nisi vitae suscipit tellus mauris a diam maecenas sed enim ut sem viverra aliquet eget sit amet tellus cras adipiscing enim eu turpis
diff --git a/Tests/LibCompress/brotli-test-files/lorem2.txt.br b/Tests/LibCompress/brotli-test-files/lorem2.txt.br
new file mode 100644
index 0000000000..1f337f7a89
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/lorem2.txt.br
diff --git a/Tests/LibCompress/brotli-test-files/serenityos.html b/Tests/LibCompress/brotli-test-files/serenityos.html
new file mode 100644
index 0000000000..81893e4288
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/serenityos.html
@@ -0,0 +1,72 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>SerenityOS</title>
+    <style>
+        body { font-family: sans-serif; }
+    </style>	
+</head>
+<body>
+<img src="banner2.png" alt="SerenityOS">
+<h1>SerenityOS</h1>
+<b>A graphical Unix-like operating system for desktop computers!</b>
+
+<p>SerenityOS is a love letter to '90s user interfaces with a custom Unix-like core. It flatters with sincerity by stealing beautiful ideas from various other systems.</p>
+
+<p>Roughly speaking, the goal is a marriage between the aesthetic of late-1990s productivity software and the power-user accessibility of late-2000s *nix.</p>
+
+<p>This is a system by us, for us, based on the things we like.</p>
+
+<p><b>Project:</b></p>
+<ul>
+    <li><a href="https://github.com/SerenityOS/serenity">SerenityOS on GitHub</a></li>
+    <li><a href="https://discord.gg/serenityos">SerenityOS Discord Server</a> <font color=red>(join here to chat!)</font></li>
+    <li><a href="faq/">Frequently asked questions</a></li>
+    <li><a href="bounty/">Bug bounty program</a></li>
+</ul>
+
+<p><b>Sponsoring developers:</b></p>
+
+<ul>
+    <li>
+        <b>Andreas Kling (<a href="https://twitter.com/awesomekling">@awesomekling</a>):</b>
+        <ul>
+            <li><a href="https://github.com/sponsors/awesomekling">GitHub Sponsors</a></li>
+            <li><a href="https://www.patreon.com/serenityos">Patreon</a></li>
+        </ul>
+    </li>
+    <br>
+    <li>
+        <b>Linus Groh (<a href="https://twitter.com/linusgroh">@linusgroh</a>):</b>
+        <ul>
+            <li><a href="https://github.com/sponsors/linusg">GitHub Sponsors</a></li>
+            <li><a href="https://liberapay.com/linusg">Liberapay</a></li>
+        </ul>
+    </li>
+    <br>
+    <li>
+        <b>Sam Atkins (<a href="https://twitter.com/atkinssj">@AtkinsSJ</a>):</b>
+        <ul>
+            <li><a href="https://github.com/sponsors/AtkinsSJ">GitHub Sponsors</a></li>
+        </ul>
+    </li>
+</ul>
+
+<p><b>Other links:</b></p>
+<ul>
+    <li><a href="https://youtube.com/c/andreaskling">Andreas Kling on YouTube</a></li>
+    <li><a href="https://youtube.com/c/linusgroh">Linus Groh on YouTube</a></li>
+    <li><a href="happy/3rd/">Happy 3rd birthday! SerenityOS: Year 3 in review</a></li>
+    <li><a href="happy/2nd/">Happy 2nd birthday! SerenityOS: The second year</a></li>
+    <li><a href="happy/1st/">Happy 1st birthday! SerenityOS: From zero to HTML in a year</a></li>
+    <li><a href="https://happy-serenityos.linus.dev/">Linus's ":^)" tracker</a></li>
+    <li><a href="https://changelog.serenityos.org/">Lubrsi's commit overview, grouped by month and category</a></li>
+    <li><a href="https://github.com/SerenityOS/yaksplained">Yaksplained: detailed explanation of yak-related emojis on our Discord server <img src="https://camo.githubusercontent.com/eec2b668c9d82d25aaf61d9afec1af3923f2d9e21bddc83a9ac621254af00ee6/68747470733a2f2f63646e2e646973636f72646170702e636f6d2f656d6f6a69732f3837333637323530353330393637393735382e706e67" height="16" alt=":yakbait:"></a></li>
+</ul>
+
+<p><b>Screenshot:</b></p>
+
+<img src="screenshot-b36968c.png">
+
+</body>
+</html>
diff --git a/Tests/LibCompress/brotli-test-files/serenityos.html.br b/Tests/LibCompress/brotli-test-files/serenityos.html.br
new file mode 100644
index 0000000000..068145bc6a
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/serenityos.html.br
diff --git a/Tests/LibCompress/brotli-test-files/transform.txt b/Tests/LibCompress/brotli-test-files/transform.txt
new file mode 100644
index 0000000000..53e354727f
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/transform.txt
@@ -0,0 +1,121 @@
+//   0           ""     Identity                 ""
+//   1           ""     Identity                " "
+//   2          " "     Identity                " "
+//   3           ""     OmitFirst1               ""
+//   4           ""     FermentFirst            " "
+//   5           ""     Identity            " the "
+//   6          " "     Identity                 ""
+//   7         "s "     Identity                " "
+//   8           ""     Identity             " of "
+//   9           ""     FermentFirst             ""
+//  10           ""     Identity            " and "
+//  11           ""     OmitFirst2               ""
+//  12           ""     OmitLast1                ""
+//  13         ", "     Identity                " "
+//  14           ""     Identity               ", "
+//  15          " "     FermentFirst            " "
+//  16           ""     Identity             " in "
+//  17           ""     Identity             " to "
+//  18         "e "     Identity                " "
+//  19           ""     Identity               "\""
+//  20           ""     Identity                "."
+//  21           ""     Identity              "\">"
+//  22           ""     Identity               "\n"
+//  23           ""     OmitLast3                ""
+//  24           ""     Identity                "]"
+//  25           ""     Identity            " for "
+//  26           ""     OmitFirst3               ""
+//  27           ""     OmitLast2                ""
+//  28           ""     Identity              " a "
+//  29           ""     Identity           " that "
+//  30          " "     FermentFirst             ""
+//  31           ""     Identity               ". "
+//  32          "."     Identity                 ""
+//  33          " "     Identity               ", "
+//  34           ""     OmitFirst4               ""
+//  35           ""     Identity           " with "
+//  36           ""     Identity                "'"
+//  37           ""     Identity           " from "
+//  38           ""     Identity             " by "
+//  39           ""     OmitFirst5               ""
+//  40           ""     OmitFirst6               ""
+//  41      " the "     Identity                 ""
+//  42           ""     OmitLast4                ""
+//  43           ""     Identity           ". The "
+//  44           ""     FermentAll               ""
+//  45           ""     Identity             " on "
+//  46           ""     Identity             " as "
+//  47           ""     Identity             " is "
+//  48           ""     OmitLast7                ""
+//  49           ""     OmitLast1            "ing "
+//  50           ""     Identity             "\n\t"
+//  51           ""     Identity                ":"
+//  52          " "     Identity               ". "
+//  53           ""     Identity              "ed "
+//  54           ""     OmitFirst9               ""
+//  55           ""     OmitFirst7               ""
+//  56           ""     OmitLast6                ""
+//  57           ""     Identity                "("
+//  58           ""     FermentFirst           ", "
+//  59           ""     OmitLast8                ""
+//  60           ""     Identity             " at "
+//  61           ""     Identity              "ly "
+//  62      " the "     Identity             " of "
+//  63           ""     OmitLast5                ""
+//  64           ""     OmitLast9                ""
+//  65          " "     FermentFirst           ", "
+//  66           ""     FermentFirst           "\""
+//  67          "."     Identity                "("
+//  68           ""     FermentAll            " "
+//  69           ""     FermentFirst          "\">"
+//  70           ""     Identity              "=\""
+//  71          " "     Identity                "."
+//  72      ".com/"     Identity                 ""
+//  73      " the "     Identity         " of the "
+//  74           ""     FermentFirst            "'"
+//  75           ""     Identity          ". This "
+//  76           ""     Identity                ","
+//  77          "."     Identity                " "
+//  78           ""     FermentFirst            "("
+//  79           ""     FermentFirst            "."
+//  80           ""     Identity            " not "
+//  81          " "     Identity              "=\""
+//  82           ""     Identity              "er "
+//  83          " "     FermentAll              " "
+//  84           ""     Identity              "al "
+//  85          " "     FermentAll               ""
+//  86           ""     Identity               "='"
+//  87           ""     FermentAll             "\""
+//  88           ""     FermentFirst           ". "
+//  89          " "     Identity                "("
+//  90           ""     Identity             "ful "
+//  91          " "     FermentFirst           ". "
+//  92           ""     Identity             "ive "
+//  93           ""     Identity            "less "
+//  94           ""     FermentAll              "'"
+//  95           ""     Identity             "est "
+//  96          " "     FermentFirst            "."
+//  97           ""     FermentAll            "\">"
+//  98          " "     Identity               "='"
+//  99           ""     FermentFirst            ","
+// 100           ""     Identity             "ize "
+// 101           ""     FermentAll              "."
+// 102   "\xc2\xa0"     Identity                 ""
+// 103          " "     Identity                ","
+// 104           ""     FermentFirst          "=\""
+// 105           ""     FermentAll            "=\""
+// 106           ""     Identity             "ous "
+// 107           ""     FermentAll             ", "
+// 108           ""     FermentFirst           "='"
+// 109          " "     FermentFirst            ","
+// 110          " "     FermentAll            "=\""
+// 111          " "     FermentAll             ", "
+// 112           ""     FermentAll              ","
+// 113           ""     FermentAll              "("
+// 114           ""     FermentAll             ". "
+// 115          " "     FermentAll              "."
+// 116           ""     FermentAll             "='"
+// 117          " "     FermentAll             ". "
+// 118          " "     FermentFirst          "=\""
+// 119          " "     FermentAll             "='"
+// 120          " "     FermentFirst           "='"
diff --git a/Tests/LibCompress/brotli-test-files/transform.txt.br b/Tests/LibCompress/brotli-test-files/transform.txt.br
new file mode 100644
index 0000000000..75ccda476d
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/transform.txt.br
diff --git a/Tests/LibCompress/brotli-test-files/wellhello.txt b/Tests/LibCompress/brotli-test-files/wellhello.txt
new file mode 100644
index 0000000000..067525091c
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/wellhello.txt
@@ -0,0 +1 @@
+Well hello friends!
diff --git a/Tests/LibCompress/brotli-test-files/wellhello.txt.br b/Tests/LibCompress/brotli-test-files/wellhello.txt.br
new file mode 100644
index 0000000000..b275c71750
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/wellhello.txt.br
diff --git a/Tests/LibCompress/brotli-test-files/wellhello2.txt b/Tests/LibCompress/brotli-test-files/wellhello2.txt
new file mode 100644
index 0000000000..0cf8bb99e2
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/wellhello2.txt
@@ -0,0 +1,2 @@
+Well hello friends!
+Well hello friends!
diff --git a/Tests/LibCompress/brotli-test-files/wellhello2.txt.br b/Tests/LibCompress/brotli-test-files/wellhello2.txt.br
new file mode 100644
index 0000000000..936555b2b1
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/wellhello2.txt.br
@@ -0,0 +1 @@
+¡8
Ào¤T]«V¹beYÈ(ãäA¬SÿS#

\ No newline at end of file
diff --git a/Tests/LibCompress/brotli-test-files/zero-one.bin.br b/Tests/LibCompress/brotli-test-files/zero-one.bin.br
new file mode 100644
index 0000000000..2d4897a94e
--- /dev/null
+++ b/Tests/LibCompress/brotli-test-files/zero-one.bin.br