intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 53 insertions, 0 deletions

diff --git a/library/cpp/streams/zstd/zstd.h b/library/cpp/streams/zstd/zstd.h
new file mode 100644
index 0000000000..667a0494b7
--- /dev/null
+++ b/library/cpp/streams/zstd/zstd.h
@@ -0,0 +1,53 @@
+#pragma once
+
+#include <util/generic/ptr.h>
+#include <util/stream/input.h>
+#include <util/stream/output.h>
+
+/**
+ * @addtogroup Streams_Archs
+ * @{
+ */
+
+// @brief Stream to compress into zstd archive
+class TZstdCompress: public IOutputStream {
+public:
+    /**
+      @param slave stream to write compressed data to
+      @param quality, higher quality - slower but better compression.
+             0 is default compression (see constant ZSTD_CLEVEL_DEFAULT(3))
+             max compression is  ZSTD_MAX_CLEVEL (22)
+    */
+    explicit TZstdCompress(IOutputStream* slave, int quality = 0);
+    ~TZstdCompress() override;
+private:
+    void DoWrite(const void* buffer, size_t size) override;
+    void DoFlush() override;
+    void DoFinish() override;
+
+public:
+    class TImpl;
+    THolder<TImpl> Impl_;
+};
+
+////////////////////////////////////////////////////////////////////////////////
+
+// @brief Buffered stream to decompress from zstd archive
+class TZstdDecompress: public IInputStream {
+public:
+    /**
+      @param slave stream to read compressed data from
+      @param bufferSize approximate size of buffer compressed data is read in
+    */
+    explicit TZstdDecompress(IInputStream* slave, size_t bufferSize = 8 * 1024);
+    ~TZstdDecompress() override;
+
+private:
+    size_t DoRead(void* buffer, size_t size) override;
+
+private:
+    class TImpl;
+    THolder<TImpl> Impl_;
+};
+
+/** @} */