LibCompress: Implement Brotli decompressor

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

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());
+}