granicus.if.org Git - icinga2/blob - lib/base/fifo.hpp

   1 /******************************************************************************
   2  * Icinga 2                                                                   *
   3  * Copyright (C) 2012-2018 Icinga Development Team (https://www.icinga.com/)  *
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  19
  20 #ifndef FIFO_H
  21 #define FIFO_H
  22
  23 #include "base/i2-base.hpp"
  24 #include "base/stream.hpp"
  25
  26 namespace icinga
  27 {
  28
  29 /**
  30  * A byte-based FIFO buffer.
  31  *
  32  * @ingroup base
  33  */
  34 class FIFO final : public Stream
  35 {
  36 public:
  37         DECLARE_PTR_TYPEDEFS(FIFO);
  38
  39         static const size_t BlockSize = 512;
  40
  41         ~FIFO() override;
  42
  43         size_t Peek(void *buffer, size_t count, bool allow_partial = false) override;
  44         size_t Read(void *buffer, size_t count, bool allow_partial = false) override;
  45         void Write(const void *buffer, size_t count) override;
  46         void Close() override;
  47         bool IsEof() const override;
  48         bool SupportsWaiting() const override;
  49         bool IsDataAvailable() const override;
  50
  51         size_t GetAvailableBytes() const;
  52
  53 private:
  54         char *m_Buffer{nullptr};
  55         size_t m_DataSize{0};
  56         size_t m_AllocSize{0};
  57         size_t m_Offset{0};
  58
  59         void ResizeBuffer(size_t newSize, bool decrease);
  60         void Optimize();
  61 };
  62
  63 }
  64
  65 #endif /* FIFO_H */