5 files changed, 135 insertions, 81 deletions

diff --git a/src/common/CMakeLists.txt b/src/common/CMakeLists.txt
index 43834eb85..5639021d3 100644
--- a/src/common/CMakeLists.txt
+++ b/src/common/CMakeLists.txt
@@ -79,8 +79,6 @@ add_library(common STATIC
     common_funcs.h
     common_paths.h
     common_types.h
-    data_compression.cpp
-    data_compression.h
     file_util.cpp
     file_util.h
     hash.h
@@ -93,6 +91,8 @@ add_library(common STATIC
     logging/log.h
     logging/text_formatter.cpp
     logging/text_formatter.h
+    lz4_compression.cpp
+    lz4_compression.h
     math_util.h
     memory_hook.cpp
     memory_hook.h
diff --git a/src/common/data_compression.cpp b/src/common/data_compression.cpp
deleted file mode 100644
index fdf4907d1..000000000
--- a/src/common/data_compression.cpp
+++ /dev/null
@@ -1,56 +0,0 @@
-// Copyright 2019 yuzu Emulator Project
-// Licensed under GPLv2 or any later version
-// Refer to the license.txt file included.
-
-#pragma once
-
-#include <lz4hc.h>
-
-#include "data_compression.h"
-
-namespace Compression {
-
-std::vector<u8> CompressDataLZ4(const u8* source, std::size_t source_size,
-                                bool use_LZ4_high_compression) {
-    if (source_size > LZ4_MAX_INPUT_SIZE) {
-        // Source size exceeds LZ4 maximum input size
-        return {};
-    }
-    const auto source_size_int = static_cast<int>(source_size);
-    const int max_compressed_size = LZ4_compressBound(source_size_int);
-    std::vector<u8> compressed(max_compressed_size);
-    int compressed_size = 0;
-
-    if (use_LZ4_high_compression) {
-        compressed_size = LZ4_compress_HC(reinterpret_cast<const char*>(source),
-                                          reinterpret_cast<char*>(compressed.data()),
-                                          source_size_int, max_compressed_size, LZ4HC_CLEVEL_MAX);
-    } else {
-        compressed_size = LZ4_compress_default(reinterpret_cast<const char*>(source),
-                                               reinterpret_cast<char*>(compressed.data()),
-                                               source_size_int, max_compressed_size);
-    }
-
-    if (compressed_size <= 0) {
-        // Compression failed
-        return {};
-    }
-    compressed.resize(compressed_size);
-    return compressed;
-}
-
-std::vector<u8> DecompressDataLZ4(const std::vector<u8>& compressed,
-                                  std::size_t uncompressed_size) {
-    std::vector<u8> uncompressed(uncompressed_size);
-    const int size_check = LZ4_decompress_safe(reinterpret_cast<const char*>(compressed.data()),
-                                               reinterpret_cast<char*>(uncompressed.data()),
-                                               static_cast<int>(compressed.size()),
-                                               static_cast<int>(uncompressed.size()));
-    if (static_cast<int>(uncompressed_size) != size_check) {
-        // Decompression failed
-        return {};
-    }
-    return uncompressed;
-}
-
-} // namespace Compression
diff --git a/src/common/data_compression.h b/src/common/data_compression.h
deleted file mode 100644
index f7264b7b8..000000000
--- a/src/common/data_compression.h
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2019 yuzu Emulator Project
-// Licensed under GPLv2 or any later version
-// Refer to the license.txt file included.
-
-#pragma once
-
-#include <vector>
-
-#include "common/common_types.h"
-
-namespace Compression {
-
-// Compresses a source memory region with LZ4 and returns the compressed data in an vector. If
-// use_LZ4_high_compression is true, the LZ4 subalgortihmn LZ4HC is used with the highst possible
-// compression level. This results in a smaller compressed size, but requires more CPU time for
-// compression. Data compressed with LZ4HC can also be decompressed with the default LZ4
-// decompression function.
-std::vector<u8> CompressDataLZ4(const u8* source, std::size_t source_size,
-                                bool use_LZ4_high_compression);
-
-std::vector<u8> DecompressDataLZ4(const std::vector<u8>& compressed, std::size_t uncompressed_size);
-
-} // namespace Compression
\ No newline at end of file
diff --git a/src/common/lz4_compression.cpp b/src/common/lz4_compression.cpp
new file mode 100644
index 000000000..dc9b4a916
--- /dev/null
+++ b/src/common/lz4_compression.cpp
@@ -0,0 +1,78 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <algorithm>
+#include <lz4hc.h>
+
+#include "common/assert.h"
+#include "common/lz4_compression.h"
+
+namespace Common::Compression {
+
+std::vector<u8> CompressDataLZ4(const u8* source, std::size_t source_size) {
+    ASSERT_MSG(source_size <= LZ4_MAX_INPUT_SIZE, "Source size exceeds LZ4 maximum input size");
+
+    const auto source_size_int = static_cast<int>(source_size);
+    const int max_compressed_size = LZ4_compressBound(source_size_int);
+    std::vector<u8> compressed(max_compressed_size);
+
+    const int compressed_size = LZ4_compress_default(reinterpret_cast<const char*>(source),
+                                                     reinterpret_cast<char*>(compressed.data()),
+                                                     source_size_int, max_compressed_size);
+
+    if (compressed_size <= 0) {
+        // Compression failed
+        return {};
+    }
+
+    compressed.resize(compressed_size);
+
+    return compressed;
+}
+
+std::vector<u8> CompressDataLZ4HC(const u8* source, std::size_t source_size,
+                                  s32 compression_level) {
+    ASSERT_MSG(source_size <= LZ4_MAX_INPUT_SIZE, "Source size exceeds LZ4 maximum input size");
+
+    compression_level = std::clamp(compression_level, LZ4HC_CLEVEL_MIN, LZ4HC_CLEVEL_MAX);
+
+    const auto source_size_int = static_cast<int>(source_size);
+    const int max_compressed_size = LZ4_compressBound(source_size_int);
+    std::vector<u8> compressed(max_compressed_size);
+
+    const int compressed_size = LZ4_compress_HC(
+        reinterpret_cast<const char*>(source), reinterpret_cast<char*>(compressed.data()),
+        source_size_int, max_compressed_size, compression_level);
+
+    if (compressed_size <= 0) {
+        // Compression failed
+        return {};
+    }
+
+    compressed.resize(compressed_size);
+
+    return compressed;
+}
+
+std::vector<u8> CompressDataLZ4HCMax(const u8* source, std::size_t source_size) {
+    return CompressDataLZ4HC(source, source_size, LZ4HC_CLEVEL_MAX);
+}
+
+std::vector<u8> DecompressDataLZ4(const std::vector<u8>& compressed,
+                                  std::size_t uncompressed_size) {
+    std::vector<u8> uncompressed(uncompressed_size);
+    const int size_check = LZ4_decompress_safe(reinterpret_cast<const char*>(compressed.data()),
+                                               reinterpret_cast<char*>(uncompressed.data()),
+                                               static_cast<int>(compressed.size()),
+                                               static_cast<int>(uncompressed.size()));
+    if (static_cast<int>(uncompressed_size) != size_check) {
+        // Decompression failed
+        return {};
+    }
+    return uncompressed;
+}
+
+} // namespace Common::Compression
diff --git a/src/common/lz4_compression.h b/src/common/lz4_compression.h
new file mode 100644
index 000000000..fe2231a6c
--- /dev/null
+++ b/src/common/lz4_compression.h
@@ -0,0 +1,55 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <vector>
+
+#include "common/common_types.h"
+
+namespace Common::Compression {
+
+/**
+ * Compresses a source memory region with LZ4 and returns the compressed data in a vector.
+ *
+ * @param source the uncompressed source memory region.
+ * @param source_size the size in bytes of the uncompressed source memory region.
+ *
+ * @return the compressed data.
+ */
+std::vector<u8> CompressDataLZ4(const u8* source, std::size_t source_size);
+
+/**
+ * Utilizes the LZ4 subalgorithm LZ4HC with the specified compression level. Higher compression
+ * levels result in a smaller compressed size, but require more CPU time for compression. The
+ * compression level has almost no impact on decompression speed. Data compressed with LZ4HC can
+ * also be decompressed with the default LZ4 decompression.
+ *
+ * @param source the uncompressed source memory region.
+ * @param source_size the size in bytes of the uncompressed source memory region.
+ * @param compression_level the used compression level. Should be between 3 and 12.
+ *
+ * @return the compressed data.
+ */
+std::vector<u8> CompressDataLZ4HC(const u8* source, std::size_t source_size, s32 compression_level);
+
+/**
+ * Utilizes the LZ4 subalgorithm LZ4HC with the highest possible compression level.
+ *
+ * @param source the uncompressed source memory region.
+ * @param source_size the size in bytes of the uncompressed source memory region.
+ *
+ * @return the compressed data.
+ */
+std::vector<u8> CompressDataLZ4HCMax(const u8* source, std::size_t source_size);
+
+/**
+ * Decompresses a source memory region with LZ4 and returns the uncompressed data in a vector.
+ *
+ * @param compressed the compressed source memory region.
+ * @param uncompressed_size the size in bytes of the uncompressed data.
+ *
+ * @return the decompressed data.
+ */
+std::vector<u8> DecompressDataLZ4(const std::vector<u8>& compressed, std::size_t uncompressed_size);
+
+} // namespace Common::Compression
\ No newline at end of file