YQ Connector: move tests from yql to ydb (OSS)

Перенос папки с тестами на Коннектор из папки yql в папку ydb (синхронизируется с github).

1 files changed, 60 insertions, 0 deletions

diff --git a/contrib/clickhouse/src/IO/MMappedFileDescriptor.h b/contrib/clickhouse/src/IO/MMappedFileDescriptor.h
new file mode 100644
index 0000000000..2611093643
--- /dev/null
+++ b/contrib/clickhouse/src/IO/MMappedFileDescriptor.h
@@ -0,0 +1,60 @@
+#pragma once
+
+#include <cstddef>
+#include <Common/CurrentMetrics.h>
+
+namespace CurrentMetrics
+{
+    extern const Metric MMappedFiles;
+    extern const Metric MMappedFileBytes;
+}
+
+
+namespace DB
+{
+
+/// MMaps a region in file (or a whole file) into memory. Unmaps in destructor.
+/// Does not open or close file.
+class MMappedFileDescriptor
+{
+public:
+    MMappedFileDescriptor(int fd_, size_t offset_, size_t length_);
+    MMappedFileDescriptor(int fd_, size_t offset_);
+
+    /// Makes empty object that can be initialized with `set`.
+    MMappedFileDescriptor() = default;
+
+    virtual ~MMappedFileDescriptor();
+
+    char * getData() { return data; }
+    const char * getData() const { return data; }
+
+    int getFD() const { return fd; }
+    size_t getOffset() const { return offset; }
+    size_t getLength() const { return length; }
+
+    /// Unmap memory before call to destructor
+    void finish();
+
+    /// Initialize or reset to another fd.
+    void set(int fd_, size_t offset_, size_t length_);
+    void set(int fd_, size_t offset_);
+
+    MMappedFileDescriptor(const MMappedFileDescriptor &) = delete;
+    MMappedFileDescriptor(MMappedFileDescriptor &&) = delete;
+
+protected:
+
+    void init();
+
+    int fd = -1;
+    size_t offset = 0;
+    size_t length = 0;
+    char * data = nullptr;
+
+    CurrentMetrics::Increment files_metric_increment{CurrentMetrics::MMappedFiles, 0};
+    CurrentMetrics::Increment bytes_metric_increment{CurrentMetrics::MMappedFileBytes, 0};
+};
+
+}
+