LZ4 compression support (#1654)

* #include an absolute path didn't work - because paths were taken to always be relative.

* Testing out use of lz4.

* Added ICompressionSystem, and LZ4 implementation.

* Add support for deflate compression.
Simplify compression interface - to make more easily work across apis.

* WIP on CompressedFileSystem.

* ImplicitDirectoryCollector

* SubStringIndexMap - > StringSliceIndexMap.

* WIP save stdlib in different containers.

* Support for different archive types for stdlib.

* Fix project.

* CompressedFileSystem -> ArchiveFileSystem.
Added CompressionSystemType::None

* Added ArchiveFileSystem

* Fix problem RiffFileSystem load withoug compression system.

* Test archive types.
Improve diagnostic message.

* Fix typo in testing file system archives.

* Split out archive detection.

* Fix gcc warning issue.

* Fix warning.

* RiffArchiveFileSystem -> RiffFileSystem

Co-authored-by: Tim Foley <tfoleyNV@users.noreply.github.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/source/core/slang-lz4-compression-system.cpp b/source/core/slang-lz4-compression-system.cpp
new file mode 100644
index 000000000..fa5c5f5ab
--- /dev/null
+++ b/source/core/slang-lz4-compression-system.cpp
@@ -0,0 +1,71 @@
+#include "slang-lz4-compression-system.h"
+
+#include "../../slang-com-helper.h"
+#include "../../slang-com-ptr.h"
+
+#include "slang-blob.h"
+
+#include "../../external/lz4/lib/lz4.h"
+
+namespace Slang
+{
+
+// Allocate static const storage for the various interface IDs that the Slang API needs to expose
+static const Guid IID_ISlangUnknown = SLANG_UUID_ISlangUnknown;
+static const Guid IID_ICompressionSystem = SLANG_UUID_ICompressionSystem;
+
+class LZ4CompressionSystemImpl : public RefObject, public ICompressionSystem 
+{
+public:
+    // ISlangUnknown 
+    // override ref counting, as singleton
+    SLANG_IUNKNOWN_QUERY_INTERFACE
+    SLANG_NO_THROW uint32_t SLANG_MCALL addRef() SLANG_OVERRIDE { return 1; }
+    SLANG_NO_THROW uint32_t SLANG_MCALL release() SLANG_OVERRIDE { return 1; }
+
+    // ICompressionSystem
+    virtual SLANG_NO_THROW CompressionSystemType SLANG_MCALL getSystemType() SLANG_OVERRIDE { return CompressionSystemType::LZ4; }
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL compress(const CompressionStyle* style, const void* src, size_t srcSizeInBytes, ISlangBlob** outBlob) SLANG_OVERRIDE;
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL decompress(const void* compressed, size_t compressedSizeInBytes, size_t decompressedSizeInBytes, void* outDecompressed) SLANG_OVERRIDE;
+
+protected:
+
+    ICompressionSystem* getInterface(const Guid& guid);
+};
+
+ICompressionSystem* LZ4CompressionSystemImpl::getInterface(const Guid& guid)
+{
+    return (guid == IID_ISlangUnknown || guid == IID_ICompressionSystem) ? static_cast<ICompressionSystem*>(this) : nullptr;
+}
+
+SlangResult LZ4CompressionSystemImpl::compress(const CompressionStyle* style, const void* src, size_t srcSizeInBytes, ISlangBlob** outBlob)
+{
+    SLANG_UNUSED(style);
+    const size_t compressedBound = LZ4_compressBound(int(srcSizeInBytes));
+
+    ScopedAllocation alloc;
+    void* compressedData = alloc.allocate(compressedBound);
+
+    const int compressedSize = LZ4_compress_default((const char*)src, (char*)compressedData, int(srcSizeInBytes), int(compressedBound));
+    alloc.reallocate(compressedSize);
+
+    auto blob = RawBlob::moveCreate(alloc);
+
+    *outBlob = blob.detach();
+    return SLANG_OK;
+}
+
+SlangResult LZ4CompressionSystemImpl::decompress(const void* compressed, size_t compressedSizeInBytes, size_t decompressedSizeInBytes, void* outDecompressed)
+{
+    const int decompressedSize = LZ4_decompress_safe((const char*)compressed, (char*)outDecompressed, int(compressedSizeInBytes), int(decompressedSizeInBytes));
+    SLANG_ASSERT(size_t(decompressedSize) == decompressedSizeInBytes);
+    return SLANG_OK;
+}
+
+/* static */ICompressionSystem* LZ4CompressionSystem::getSingleton()
+{
+    static LZ4CompressionSystemImpl impl;
+    return &impl;
+}
+
+} // namespace Slang