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27 lines
781 B
C++
27 lines
781 B
C++
#pragma once
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#include <IO/ReadBuffer.h>
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#include <IO/ReadBufferFromFileBase.h>
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namespace DB
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{
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/// In case of empty file it does not make any sense to read it.
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///
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/// Plus regular readers from file has an assert that buffer is not empty, that will fail:
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/// - ReadBufferFromFileDescriptor
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/// - SynchronousReader
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/// - ThreadPoolReader
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class ReadBufferFromEmptyFile : public ReadBufferFromFileBase
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{
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private:
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bool nextImpl() override { return false; }
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std::string getFileName() const override { return "<empty>"; }
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off_t seek(off_t /*off*/, int /*whence*/) override { return 0; }
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off_t getPosition() override { return 0; }
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std::optional<size_t> tryGetFileSize() override { return 0; }
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size_t getFileOffsetOfBufferEnd() const override { return 0; }
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};
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}
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