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1// @(#)root/io
2// Author: Rene Brun 28/12/94
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 *************************************************************************/
12#ifndef ROOT_TKey
13#define ROOT_TKey
15#include "TNamed.h"
16#include "TDatime.h"
17#include "TBuffer.h"
18#include "TClass.h"
20class TBrowser;
21class TDirectory;
22class TFile;
24class TKey : public TNamed {
29 kReproducible = BIT(15)
30 };
31 TKey(const TKey&) = delete; // TKey objects are not copiable.
32 TKey& operator=(const TKey&) = delete; // TKey objects are not copiable.
35 Int_t fVersion; ///< Key version identifier
36 Int_t fNbytes; ///< Number of bytes for the object on file
37 Int_t fObjlen; ///< Length of uncompressed object in bytes
38 TDatime fDatime; ///< Date/Time of insertion in file
39 Short_t fKeylen; ///< Number of bytes for the key itself
40 Short_t fCycle; ///< Cycle number
41 Long64_t fSeekKey; ///< Location of object on file
42 Long64_t fSeekPdir; ///< Location of parent directory on file
43 TString fClassName; ///< Object Class name
44 Int_t fLeft; ///< Number of bytes left in current segment
45 char *fBuffer; ///< Object buffer
46 TBuffer *fBufferRef; ///< Pointer to the TBuffer object
47 UShort_t fPidOffset; ///<!Offset to be added to the pid index in this key/buffer. This is actually saved in the high bits of fSeekPdir
48 TDirectory *fMotherDir; ///<!pointer to mother directory
50 virtual Int_t Read(const char *name) { return TObject::Read(name); }
51 virtual void Create(Int_t nbytes, TFile* f = 0);
52 void Build(TDirectory* motherDir, const char* classname, Long64_t filepos);
53 void Reset(); // Currently only for the use of TBasket.
54 virtual Int_t WriteFileKeepBuffer(TFile *f = 0);
57 public:
58 TKey();
59 TKey(TDirectory* motherDir);
60 TKey(TDirectory* motherDir, const TKey &orig, UShort_t pidOffset);
61 TKey(const char *name, const char *title, const TClass *cl, Int_t nbytes, TDirectory* motherDir);
62 TKey(const TString &name, const TString &title, const TClass *cl, Int_t nbytes, TDirectory* motherDir);
63 TKey(const TObject *obj, const char *name, Int_t bufsize, TDirectory* motherDir);
64 TKey(const void *obj, const TClass *cl, const char *name, Int_t bufsize, TDirectory* motherDir);
65 TKey(Long64_t pointer, Int_t nbytes, TDirectory* motherDir = 0);
66 virtual ~TKey();
68 virtual void Browse(TBrowser *b);
69 virtual void Delete(Option_t *option="");
70 virtual void DeleteBuffer();
71 virtual void FillBuffer(char *&buffer);
72 virtual const char *GetClassName() const {return fClassName.Data();}
73 virtual const char *GetIconName() const;
74 virtual const char *GetTitle() const;
75 virtual char *GetBuffer() const {return fBuffer+fKeylen;}
76 TBuffer *GetBufferRef() const {return fBufferRef;}
77 Short_t GetCycle() const;
78 const TDatime &GetDatime() const {return fDatime;}
79 TFile *GetFile() const;
80 Short_t GetKeep() const;
81 Int_t GetKeylen() const {return fKeylen;}
82 TDirectory* GetMotherDir() const { return fMotherDir; }
83 Int_t GetNbytes() const {return fNbytes;}
84 Int_t GetObjlen() const {return fObjlen;}
85 Int_t GetVersion() const {return fVersion;}
86 virtual Long64_t GetSeekKey() const {return fSeekKey;}
87 virtual Long64_t GetSeekPdir() const {return fSeekPdir;}
88 virtual void IncrementPidOffset(UShort_t offset);
89 Bool_t IsFolder() const;
90 virtual void Keep();
91 virtual void ls(Option_t *option="") const;
92 virtual void Print(Option_t *option="") const;
93 virtual Int_t Read(TObject *obj);
94 virtual TObject *ReadObj();
95 virtual TObject *ReadObjWithBuffer(char *bufferRead);
96 /// To read an object (non deriving from TObject) from the file.
97 /// This is more user friendly version of TKey::ReadObjectAny.
98 /// See TKey::ReadObjectAny for more details.
99 template <typename T> T *ReadObject() {
100 return reinterpret_cast<T*>(ReadObjectAny(TClass::GetClass<T>()));
101 }
102 virtual void *ReadObjectAny(const TClass *expectedClass);
103 virtual void ReadBuffer(char *&buffer);
104 void ReadKeyBuffer(char *&buffer);
105 virtual Bool_t ReadFile();
106 virtual void SetBuffer() { fBuffer = new char[fNbytes];}
107 virtual void SetParent(const TObject *parent);
108 void SetMotherDir(TDirectory* dir) { fMotherDir = dir; }
109 virtual Int_t Sizeof() const;
110 virtual Int_t WriteFile(Int_t cycle=1, TFile* f = 0);
112 ClassDef(TKey,4); //Header description of a logical record on file.
#define b(i)
Definition: RSha256.hxx:100
#define f(i)
Definition: RSha256.hxx:104
unsigned short UShort_t
Definition: RtypesCore.h:36
int Int_t
Definition: RtypesCore.h:41
bool Bool_t
Definition: RtypesCore.h:59
short Short_t
Definition: RtypesCore.h:35
long long Long64_t
Definition: RtypesCore.h:69
const char Option_t
Definition: RtypesCore.h:62
#define ClassDef(name, id)
Definition: Rtypes.h:326
#define BIT(n)
Definition: Rtypes.h:83
char name[80]
Definition: TGX11.cxx:109
Using a TBrowser one can browse all ROOT objects.
Definition: TBrowser.h:37
Buffer base class used for serializing objects.
Definition: TBuffer.h:42
TClass instances represent classes, structs and namespaces in the ROOT type system.
Definition: TClass.h:75
This class stores the date and time with a precision of one second in an unsigned 32 bit word (950130...
Definition: TDatime.h:37
Describe directory structure in memory.
Definition: TDirectory.h:34
A ROOT file is a suite of consecutive data records (TKey instances) with a well defined format.
Definition: TFile.h:48
Book space in a file, create I/O buffers, to fill them, (un)compress them.
Definition: TKey.h:24
virtual void Print(Option_t *option="") const
Print key contents.
Definition: TKey.cxx:693
@ kReproducible
Definition: TKey.h:29
@ kIsDirectoryFile
Definition: TKey.h:28
virtual Long64_t GetSeekKey() const
Definition: TKey.h:86
virtual void FillBuffer(char *&buffer)
Encode key header into output buffer.
Definition: TKey.cxx:592
TKey default constructor.
Definition: TKey.cxx:89
virtual void Delete(Option_t *option="")
Delete an object from the file.
Definition: TKey.cxx:538
TFile * GetFile() const
Returns file to which key belong.
Definition: TKey.cxx:576
virtual void Keep()
Set the "KEEP" status.
Definition: TKey.cxx:676
virtual Int_t WriteFileKeepBuffer(TFile *f=0)
Write the encoded object supported by this key.
Definition: TKey.cxx:1470
virtual const char * GetIconName() const
Title can keep 32x32 xpm thumbnail/icon of the parent object.
Definition: TKey.cxx:1503
Int_t GetVersion() const
Definition: TKey.h:85
virtual Int_t Read(const char *name)
Read contents of object with specified name from the current directory.
Definition: TKey.h:50
virtual void ls(Option_t *option="") const
List Key contents.
Definition: TKey.cxx:684
Int_t GetKeylen() const
Definition: TKey.h:81
TDatime fDatime
Date/Time of insertion in file.
Definition: TKey.h:38
Int_t GetObjlen() const
Definition: TKey.h:84
TBuffer * fBufferRef
Pointer to the TBuffer object.
Definition: TKey.h:46
T * ReadObject()
To read an object (non deriving from TObject) from the file.
Definition: TKey.h:99
UShort_t fPidOffset
!Offset to be added to the pid index in this key/buffer. This is actually saved in the high bits of f...
Definition: TKey.h:47
Int_t GetNbytes() const
Definition: TKey.h:83
virtual void IncrementPidOffset(UShort_t offset)
Increment fPidOffset by 'offset'.
Definition: TKey.cxx:641
Short_t GetKeep() const
Returns the "KEEP" status.
Definition: TKey.cxx:584
Int_t fVersion
Key version identifier.
Definition: TKey.h:35
virtual ~TKey()
TKey default destructor.
Definition: TKey.cxx:524
Int_t fLeft
Number of bytes left in current segment.
Definition: TKey.h:44
virtual const char * GetClassName() const
Definition: TKey.h:72
virtual void Create(Int_t nbytes, TFile *f=0)
Create a TKey object of specified size.
Definition: TKey.cxx:458
virtual const char * GetTitle() const
Returns title (title can contain 32x32 xpm thumbnail/icon).
Definition: TKey.cxx:1511
Short_t fKeylen
Number of bytes for the key itself.
Definition: TKey.h:39
virtual Bool_t ReadFile()
Read the key structure from the file.
Definition: TKey.cxx:1244
virtual Int_t WriteFile(Int_t cycle=1, TFile *f=0)
Write the encoded object supported by this key.
Definition: TKey.cxx:1429
virtual void SetBuffer()
Definition: TKey.h:106
TKey(const TKey &)=delete
const TDatime & GetDatime() const
Definition: TKey.h:78
Long64_t fSeekKey
Location of object on file.
Definition: TKey.h:41
void Build(TDirectory *motherDir, const char *classname, Long64_t filepos)
Method used in all TKey constructor to initialize basic data fields.
Definition: TKey.cxx:388
char * fBuffer
Object buffer.
Definition: TKey.h:45
Long64_t fSeekPdir
Location of parent directory on file.
Definition: TKey.h:42
virtual void SetParent(const TObject *parent)
Set parent in key buffer.
Definition: TKey.cxx:1273
Bool_t IsFolder() const
Check if object referenced by the key is a folder.
Definition: TKey.cxx:655
virtual void * ReadObjectAny(const TClass *expectedClass)
To read an object (non deriving from TObject) from the file.
Definition: TKey.cxx:994
void ReadKeyBuffer(char *&buffer)
Decode input buffer.
Definition: TKey.cxx:1201
Int_t fNbytes
Number of bytes for the object on file.
Definition: TKey.h:36
Int_t fObjlen
Length of uncompressed object in bytes.
Definition: TKey.h:37
void Reset()
Reset the key as it had not been 'filled' yet.
Definition: TKey.cxx:1281
TKey & operator=(const TKey &)=delete
virtual Long64_t GetSeekPdir() const
Definition: TKey.h:87
void SetMotherDir(TDirectory *dir)
Definition: TKey.h:108
Short_t fCycle
Cycle number.
Definition: TKey.h:40
virtual TObject * ReadObjWithBuffer(char *bufferRead)
To read a TObject* from bufferRead.
Definition: TKey.cxx:863
TDirectory * GetMotherDir() const
Definition: TKey.h:82
Short_t GetCycle() const
Return cycle number associated to this key.
Definition: TKey.cxx:568
virtual TObject * ReadObj()
To read a TObject* from the file.
Definition: TKey.cxx:729
virtual void DeleteBuffer()
Delete key buffer(s).
Definition: TKey.cxx:550
virtual char * GetBuffer() const
Definition: TKey.h:75
virtual Int_t Sizeof() const
Return the size in bytes of the key header structure.
Definition: TKey.cxx:1315
virtual void ReadBuffer(char *&buffer)
Decode input buffer.
Definition: TKey.cxx:1189
TDirectory * fMotherDir
!pointer to mother directory
Definition: TKey.h:48
virtual void Browse(TBrowser *b)
Read object from disk and call its Browse() method.
Definition: TKey.cxx:426
TString fClassName
Object Class name.
Definition: TKey.h:43
TBuffer * GetBufferRef() const
Definition: TKey.h:76
The TNamed class is the base class for all named ROOT classes.
Definition: TNamed.h:29
Mother of all ROOT objects.
Definition: TObject.h:37
Definition: TObject.h:57
virtual Int_t Read(const char *name)
Read contents of object with specified name from the current directory.
Definition: TObject.cxx:562
Basic string class.
Definition: TString.h:131
const char * Data() const
Definition: TString.h:364
double T(double x)
Definition: ChebyshevPol.h:34