ringbuffer.h

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/*
 * ringbuffer.h: A ring buffer
 *
 * See the main source file 'vdr.c' for copyright information and
 * how to reach the author.
 *
 * $Id: ringbuffer.h 5.3 2026/09/03 13:44:36 kls Exp $
 */
 
#ifndef __RINGBUFFER_H
#define __RINGBUFFER_H
 
#include <atomic>
#include "thread.h"
#include "tools.h"
 
class cRingBuffer {
private:
  cCondWait readyForPut, readyForGet;
  int putTimeout;
  int getTimeout;
  int size;
  time_t lastOverflowReport;
  int overflowCount;
  int overflowBytes;
  cIoThrottle *ioThrottle;
protected:
  std::atomic<tThreadId> getThreadTid; // set by the reading thread, logged by the writing one
  int maxFill;//XXX
  int lastPercent;
  bool statistics;//XXX
  void UpdatePercentage(int Fill);
  void WaitForPut(void);
  void WaitForGet(void);
  void EnablePut(void);
  void EnableGet(void);
  virtual void Clear(void) = 0;
  virtual int Available(void) = 0;
  virtual int Free(void) { return Size() - Available() - 1; }
  int Size(void) { return size; }
public:
  cRingBuffer(int Size, bool Statistics = false);
  virtual ~cRingBuffer();
  void SetTimeouts(int PutTimeout, int GetTimeout);
  void SetIoThrottle(void);
  void ReportOverflow(int Bytes);
  };
 
class cRingBufferLinear : public cRingBuffer {
//#define DEBUGRINGBUFFERS
#ifdef DEBUGRINGBUFFERS
private:
  int lastHead, lastTail;
  int lastPut, lastGet;
  static cRingBufferLinear *RBLS[];
  static void AddDebugRBL(cRingBufferLinear *RBL);
  static void DelDebugRBL(cRingBufferLinear *RBL);
public:
  static void PrintDebugRBL(void);
#endif
private:
  int margin;
  std::atomic<int> head, tail;
  int gotten;
  uchar *buffer;
  char *description;
protected:
  virtual int DataReady(const uchar *Data, int Count);
public:
  cRingBufferLinear(int Size, int Margin = 0, bool Statistics = false, const char *Description = NULL);
  virtual ~cRingBufferLinear() override;
  virtual int Available(void) override;
  virtual int Free(void) override { return Size() - Available() - 1 - margin; }
  virtual void Clear(void) override;
  int Read(int FileHandle, int Max = 0);
  int Read(cUnbufferedFile *File, int Max = 0);
  int Put(const uchar *Data, int Count);
  uchar *Get(int &Count);
  void Del(int Count);
  };
 
enum eFrameType { ftUnknown, ftVideo, ftAudio, ftDolby };
 
class cFrame {
  friend class cRingBufferFrame;
private:
  cFrame *next;
  uchar *data;
  int count;
  eFrameType type;
  int index;
  uint32_t pts;
  bool independent;
public:
  cFrame(const uchar *Data, int Count, eFrameType = ftUnknown, int Index = -1, uint32_t Pts = 0, bool independent = false);
  ~cFrame();
  uchar *Data(void) const { return data; }
  int Count(void) const { return count; }
  eFrameType Type(void) const { return type; }
  int Index(void) const { return index; }
  uint32_t Pts(void) const { return pts; }
  bool Independent(void) const { return independent; }
  };
 
class cRingBufferFrame : public cRingBuffer {
private:
  cMutex mutex;
  cFrame *head;
  int currentFill;
  void Delete(cFrame *Frame);
  void Lock(void) { mutex.Lock(); }
  void Unlock(void) { mutex.Unlock(); }
public:
  cRingBufferFrame(int Size, bool Statistics = false);
  virtual ~cRingBufferFrame() override;
  virtual int Available(void) override;
  virtual void Clear(void) override;
    // Immediately clears the ring buffer.
  bool Put(cFrame *Frame);
    // Puts the Frame into the ring buffer.
    // Returns true if this was possible.
  cFrame *Get(void);
    // Gets the next frame from the ring buffer.
    // The actual data still remains in the buffer until Drop() is called.
  void Drop(cFrame *Frame);
    // Drops the Frame that has just been fetched with Get().
  };
 
#endif //__RINGBUFFER_H