Logo ROOT  
Reference Guide
TBufferIO.h
Go to the documentation of this file.
1// @(#)root/io:$Id$
2// Author: Sergey Linev 21/02/2018
3
4/*************************************************************************
5 * Copyright (C) 1995-2018, 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_TBufferIO
13#define ROOT_TBufferIO
14
15//////////////////////////////////////////////////////////////////////////
16// //
17// TBufferIO //
18// //
19// Direct subclass of TBuffer, implements common methods for //
20// TBufferFile and TBufferText classes //
21// //
22//////////////////////////////////////////////////////////////////////////
23
24#include "TBuffer.h"
25
26#include "TString.h"
27
28class TExMap;
29
30class TBufferIO : public TBuffer {
31
32protected:
33 enum { kNullTag = 0 }; ///< tag value for nullptr in objects map
34
35 Int_t fMapCount{0}; ///< Number of objects or classes in map
36 Int_t fMapSize{0}; ///< Default size of map
37 Int_t fDisplacement{0}; ///< Value to be added to the map offsets
38 UShort_t fPidOffset{0}; ///< Offset to be added to the pid index in this key/buffer.
39 TExMap *fMap{nullptr}; ///< Map containing object,offset pairs for reading/writing
40 TExMap *fClassMap{nullptr}; ///< Map containing object,class pairs for reading
41
42 static Int_t fgMapSize; ///< Default map size for all TBuffer objects
43
44 TBufferIO() {} // NOLINT: not allowed to use = default because of TObject::kIsOnHeap detection, see ROOT-10300
45
47 TBufferIO(TBuffer::EMode mode, Int_t bufsiz);
48 TBufferIO(TBuffer::EMode mode, Int_t bufsiz, void *buf, Bool_t adopt = kTRUE,
49 ReAllocCharFun_t reallocfunc = nullptr);
50
51 ////////////////////////////////////////////////////////////////////////////////
52 /// Return hash value for provided object.
53 static R__ALWAYS_INLINE ULong_t Void_Hash(const void *ptr) { return TString::Hash(&ptr, sizeof(void *)); }
54
55 // method used in TBufferFile, keep here for full compatibility
56 virtual void CheckCount(UInt_t) {}
57
58 Long64_t GetObjectTag(const void *obj);
59
60 virtual void WriteObjectClass(const void *actualObjStart, const TClass *actualClass, Bool_t cacheReuse) = 0;
61
62public:
63 enum { kMapSize = 503 }; ///< default objects map size
64
66 kNotDecompressed = BIT(15), // indicates a weird buffer, used by TBasket
67 kTextBasedStreaming = BIT(18), // indicates if buffer used for XML/SQL object streaming
68
69 kUser1 = BIT(21), // free for user
70 kUser2 = BIT(22), // free for user
71 kUser3 = BIT(23) // free for user
72 };
73
74 virtual ~TBufferIO();
75
76 Int_t GetVersionOwner() const override;
77
78 // See comment in TBuffer::SetPidOffset
79 UShort_t GetPidOffset() const override { return fPidOffset; }
80 void SetPidOffset(UShort_t offset) override;
81 Int_t GetBufferDisplacement() const override { return fDisplacement; }
82 void SetBufferDisplacement() override { fDisplacement = 0; }
83 void SetBufferDisplacement(Int_t skipped) override { fDisplacement = (Int_t)(Length() - skipped); }
84
85 // Utilities for objects map
86 void SetReadParam(Int_t mapsize) override;
87 void SetWriteParam(Int_t mapsize) override;
88 void InitMap() override;
89 void ResetMap() override;
90 void Reset() override;
91 Int_t GetMapCount() const override { return fMapCount; }
92 void MapObject(const TObject *obj, UInt_t offset = 1) override;
93 void MapObject(const void *obj, const TClass *cl, UInt_t offset = 1) override;
94 Bool_t CheckObject(const TObject *obj) override;
95 Bool_t CheckObject(const void *obj, const TClass *ptrClass) override;
96 void GetMappedObject(UInt_t tag, void *&ptr, TClass *&ClassPtr) const override;
97
98 // Utilities for TStreamerInfo
99 void ForceWriteInfo(TVirtualStreamerInfo *info, Bool_t force) override;
100 void ForceWriteInfoClones(TClonesArray *a) override;
101 Int_t ReadClones(TClonesArray *a, Int_t nobjects, Version_t objvers) override;
102 Int_t WriteClones(TClonesArray *a, Int_t nobjects) override;
103 void TagStreamerInfo(TVirtualStreamerInfo *info) override;
104
105 // Special basic ROOT objects and collections
106 TProcessID *GetLastProcessID(TRefTable *reftable) const override;
107 UInt_t GetTRefExecId() override;
108 TProcessID *ReadProcessID(UShort_t pidf) override;
109 UShort_t WriteProcessID(TProcessID *pid) override;
110
111 Int_t WriteObjectAny(const void *obj, const TClass *ptrClass, Bool_t cacheReuse = kTRUE) override;
112 void WriteObject(const TObject *obj, Bool_t cacheReuse = kTRUE) override;
114
115 static void SetGlobalReadParam(Int_t mapsize);
116 static void SetGlobalWriteParam(Int_t mapsize);
117 static Int_t GetGlobalReadParam();
118 static Int_t GetGlobalWriteParam();
119
120 ClassDefOverride(TBufferIO, 0) // base class, share methods for TBufferFile and TBufferText
121};
122
123#endif
#define R__ALWAYS_INLINE
Definition: RConfig.hxx:563
unsigned short UShort_t
Definition: RtypesCore.h:40
int Int_t
Definition: RtypesCore.h:45
short Version_t
Definition: RtypesCore.h:65
unsigned int UInt_t
Definition: RtypesCore.h:46
unsigned long ULong_t
Definition: RtypesCore.h:55
bool Bool_t
Definition: RtypesCore.h:63
long long Long64_t
Definition: RtypesCore.h:80
const Bool_t kTRUE
Definition: RtypesCore.h:100
#define BIT(n)
Definition: Rtypes.h:85
#define ClassDefOverride(name, id)
Definition: Rtypes.h:329
char *(* ReAllocCharFun_t)(char *, size_t, size_t)
Definition: TStorage.h:30
Direct subclass of TBuffer, implements common methods for TBufferFile and TBufferText classes.
Definition: TBufferIO.h:30
@ kMapSize
Definition: TBufferIO.h:63
void SetWriteParam(Int_t mapsize) override
Set the initial size of the hashtable used to store object and class references during writing.
Definition: TBufferIO.cxx:117
static void SetGlobalReadParam(Int_t mapsize)
Set the initial size of the map used to store object and class references during reading.
Definition: TBufferIO.cxx:548
void Reset() override
Reset buffer object. Resets map and buffer offset.
Definition: TBufferIO.cxx:305
void InitMap() override
Create the fMap container and initialize them with the null object.
Definition: TBufferIO.cxx:129
Int_t GetVersionOwner() const override
Return the version number of the owner file.
Definition: TBufferIO.cxx:77
static void SetGlobalWriteParam(Int_t mapsize)
Set the initial size of the map used to store object and class references during reading.
Definition: TBufferIO.cxx:564
TProcessID * GetLastProcessID(TRefTable *reftable) const override
Return the last TProcessID in the file.
Definition: TBufferIO.cxx:399
void ForceWriteInfo(TVirtualStreamerInfo *info, Bool_t force) override
force writing the TStreamerInfo to the file
Definition: TBufferIO.cxx:329
void ForceWriteInfoClones(TClonesArray *a) override
Make sure TStreamerInfo is not optimized, otherwise it will not be possible to support schema evoluti...
Definition: TBufferIO.cxx:341
UShort_t GetPidOffset() const override
Definition: TBufferIO.h:79
virtual void WriteObjectClass(const void *actualObjStart, const TClass *actualClass, Bool_t cacheReuse)=0
TExMap * fMap
Map containing object,offset pairs for reading/writing.
Definition: TBufferIO.h:39
@ kTextBasedStreaming
Definition: TBufferIO.h:67
@ kNotDecompressed
Definition: TBufferIO.h:66
void SetReadParam(Int_t mapsize) override
Set the initial size of the map used to store object and class references during reading.
Definition: TBufferIO.cxx:97
Bool_t CheckObject(const TObject *obj) override
Check if the specified object is already in the buffer.
Definition: TBufferIO.cxx:225
void WriteObject(const TObject *obj, Bool_t cacheReuse=kTRUE) override
Write object to I/O buffer.
Definition: TBufferIO.cxx:530
void MapObject(const TObject *obj, UInt_t offset=1) override
Add object to the fMap container.
Definition: TBufferIO.cxx:163
Long64_t GetObjectTag(const void *obj)
Returns tag for specified object from objects map (if exists) Returns 0 if object not included into o...
Definition: TBufferIO.cxx:277
@ kNullTag
Definition: TBufferIO.h:33
Int_t WriteClones(TClonesArray *a, Int_t nobjects) override
Interface to TStreamerInfo::WriteBufferClones.
Definition: TBufferIO.cxx:385
UShort_t WriteProcessID(TProcessID *pid) override
Check if the ProcessID pid is already in the file.
Definition: TBufferIO.cxx:456
TExMap * fClassMap
Map containing object,class pairs for reading.
Definition: TBufferIO.h:40
Int_t fDisplacement
Value to be added to the map offsets.
Definition: TBufferIO.h:37
static R__ALWAYS_INLINE ULong_t Void_Hash(const void *ptr)
Return hash value for provided object.
Definition: TBufferIO.h:53
virtual ~TBufferIO()
destructor
Definition: TBufferIO.cxx:68
virtual void CheckCount(UInt_t)
Definition: TBufferIO.h:56
Int_t fMapCount
Number of objects or classes in map.
Definition: TBufferIO.h:35
void SetBufferDisplacement(Int_t skipped) override
Definition: TBufferIO.h:83
static Int_t GetGlobalReadParam()
Get default read map size.
Definition: TBufferIO.cxx:572
TBufferIO()
Definition: TBufferIO.h:44
void TagStreamerInfo(TVirtualStreamerInfo *info) override
Mark the classindex of the current file as using this TStreamerInfo.
Definition: TBufferIO.cxx:350
static Int_t fgMapSize
Default map size for all TBuffer objects.
Definition: TBufferIO.h:42
void ResetMap() override
Delete existing fMap and reset map counter.
Definition: TBufferIO.cxx:288
TProcessID * ReadProcessID(UShort_t pidf) override
The TProcessID with number pidf is read from file.
Definition: TBufferIO.cxx:422
UShort_t fPidOffset
Offset to be added to the pid index in this key/buffer.
Definition: TBufferIO.h:38
Int_t ReadClones(TClonesArray *a, Int_t nobjects, Version_t objvers) override
Interface to TStreamerInfo::ReadBufferClones.
Definition: TBufferIO.cxx:372
void SetBufferDisplacement() override
Definition: TBufferIO.h:82
void GetMappedObject(UInt_t tag, void *&ptr, TClass *&ClassPtr) const override
Retrieve the object stored in the buffer's object map at 'tag' Set ptr and ClassPtr respectively to t...
Definition: TBufferIO.cxx:260
Int_t WriteObjectAny(const void *obj, const TClass *ptrClass, Bool_t cacheReuse=kTRUE) override
Write object to I/O buffer.
Definition: TBufferIO.cxx:492
Int_t GetMapCount() const override
Definition: TBufferIO.h:91
void SetPidOffset(UShort_t offset) override
This offset is used when a key (or basket) is transfered from one file to the other.
Definition: TBufferIO.cxx:319
Int_t GetBufferDisplacement() const override
Definition: TBufferIO.h:81
Int_t fMapSize
Default size of map.
Definition: TBufferIO.h:36
static Int_t GetGlobalWriteParam()
Get default write map size.
Definition: TBufferIO.cxx:580
UInt_t GetTRefExecId() override
Return the exec id stored in the current TStreamerInfo element.
Definition: TBufferIO.cxx:447
Buffer base class used for serializing objects.
Definition: TBuffer.h:43
EStatusBits
Definition: TBuffer.h:74
virtual void WriteObject(const TObject *obj, Bool_t cacheReuse)=0
Int_t Length() const
Definition: TBuffer.h:100
TClass instances represent classes, structs and namespaces in the ROOT type system.
Definition: TClass.h:80
An array of clone (identical) objects.
Definition: TClonesArray.h:29
This class stores a (key,value) pair using an external hash.
Definition: TExMap.h:33
Mother of all ROOT objects.
Definition: TObject.h:37
A TProcessID identifies a ROOT job in a unique way in time and space.
Definition: TProcessID.h:74
A TRefTable maintains the association between a referenced object and the parent object supporting th...
Definition: TRefTable.h:35
UInt_t Hash(ECaseCompare cmp=kExact) const
Return hash value.
Definition: TString.cxx:662
Abstract Interface class describing Streamer information for one class.
auto * a
Definition: textangle.C:12