Logo ROOT   6.21/01
Reference Guide
TFileCacheWrite.h
Go to the documentation of this file.
1 // @(#)root/io:$Id$
2 // Author: Rene Brun 19/05/2006
3 
4 /*************************************************************************
5  * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
6  * All rights reserved. *
7  * *
8  * For the licensing terms see $ROOTSYS/LICENSE. *
9  * For the list of contributors see $ROOTSYS/README/CREDITS. *
10  *************************************************************************/
11 
12 #ifndef ROOT_TFileCacheWrite
13 #define ROOT_TFileCacheWrite
14 
15 #include "TObject.h"
16 
17 class TFile;
18 
19 class TFileCacheWrite : public TObject {
20 
21 protected:
22  Long64_t fSeekStart; ///< Seek value of first block in cache
23  Int_t fBufferSize; ///< Allocated size of fBuffer
24  Int_t fNtot; ///< Total size of cached blocks
25  TFile *fFile; ///< Pointer to file
26  char *fBuffer; ///< [fBufferSize] buffer of contiguous prefetched blocks
27  Bool_t fRecursive; ///< flag to avoid recursive calls
28 
29 private:
30  TFileCacheWrite(const TFileCacheWrite &) = delete; //cannot be copied
31  TFileCacheWrite& operator=(const TFileCacheWrite &) = delete;
32 
33 public:
35  TFileCacheWrite(TFile *file, Int_t buffersize);
36  virtual ~TFileCacheWrite();
37  virtual Bool_t Flush();
38  virtual Int_t GetBytesInCache() const { return fNtot; }
39  virtual void Print(Option_t *option="") const;
40  virtual Int_t ReadBuffer(char *buf, Long64_t pos, Int_t len);
41  virtual Int_t WriteBuffer(const char *buf, Long64_t pos, Int_t len);
42  virtual void SetFile(TFile *file);
43 
44  ClassDef(TFileCacheWrite,1) //TFile cache when writing
45 };
46 
47 #endif
Int_t fNtot
Total size of cached blocks.
long long Long64_t
Definition: RtypesCore.h:69
TFileCacheWrite()
Default Constructor.
const char Option_t
Definition: RtypesCore.h:62
A ROOT file is a suite of consecutive data records (TKey instances) with a well defined format...
Definition: TFile.h:48
int Int_t
Definition: RtypesCore.h:41
bool Bool_t
Definition: RtypesCore.h:59
virtual Int_t GetBytesInCache() const
char * fBuffer
[fBufferSize] buffer of contiguous prefetched blocks
TFileCacheWrite & operator=(const TFileCacheWrite &)=delete
#define ClassDef(name, id)
Definition: Rtypes.h:326
virtual ~TFileCacheWrite()
Destructor.
virtual Bool_t Flush()
Flush the current write buffer to the file.
TFile * fFile
Pointer to file.
virtual Int_t ReadBuffer(char *buf, Long64_t pos, Int_t len)
Called by the read cache to check if the requested data is not in the write cache buffer...
Bool_t fRecursive
flag to avoid recursive calls
Mother of all ROOT objects.
Definition: TObject.h:37
virtual Int_t WriteBuffer(const char *buf, Long64_t pos, Int_t len)
Write buffer at position pos in the write buffer.
virtual void Print(Option_t *option="") const
Print class internal structure.
Definition: file.py:1
Int_t fBufferSize
Allocated size of fBuffer.
Long64_t fSeekStart
Seek value of first block in cache.
virtual void SetFile(TFile *file)
Set the file using this cache.
A cache when writing files over the network