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1// @(#)root/thread:$Id$
2// Author: Fons Rademakers 02/07/97
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_TThread
13#define ROOT_TThread
17// //
18// TThread //
19// //
20// This class implements threads. A thread is an execution environment //
21// much lighter than a process. A single process can have multiple //
22// threads. The actual work is done via the TThreadImp class (either //
23// TPosixThread or TWin32Thread). //
24// //
27#include "TNamed.h"
28#include "TTimer.h"
29#include <stdarg.h>
32class TCondition;
34#include "TCondition.h"
37class TMutex;
38class TThreadImp;
40class TThread : public TNamed {
42friend class TThreadImp;
43friend class TPosixThread;
44friend class TThreadTimer;
45friend class TThreadCleaner;
46friend class TWin32Thread;
48friend class TJoinHelper;
52 typedef void *(*VoidRtnFunc_t)(void *);
53 typedef void (*VoidFunc_t)(void *);
55 enum EPriority {
59 };
61 enum EState {
62 kInvalidState, // thread was not created properly
63 kNewState, // thread object exists but hasn't started
64 kRunningState, // thread is running
65 kTerminatedState, // thread has terminated but storage has not
66 // yet been reclaimed (i.e. waiting to be joined)
67 kFinishedState, // thread has finished
68 kCancelingState, // thread in process of canceling
69 kCanceledState, // thread has been canceled
70 kDeletingState // thread in process of deleting
71 };
74 TThread *fNext; // pointer to next thread
75 TThread *fPrev; // pointer to prev thread
76 TThread **fHolder; // pointer to holder of this (delete only)
77 EPriority fPriority; // thread priority
78 EState fState; // thread state
79 EState fStateComing; // coming thread state
80 Long_t fId; // thread id
81 Longptr_t fHandle; // Win32 thread handle
82 Bool_t fDetached; // kTRUE if thread is Detached
83 Bool_t fNamed; // kTRUE if thread is Named
84 VoidRtnFunc_t fFcnRetn; // void* start function of thread
85 VoidFunc_t fFcnVoid; // void start function of thread
86 void *fThreadArg; // thread start function arguments
87 void *fClean; // support of cleanup structure
88 char fComment[100]; // thread specific state comment
90 static TThreadImp *fgThreadImp; // static pointer to thread implementation
91 static std::atomic<char *> volatile fgXAct; // Action name to do by main thread
92 static void ** volatile fgXArr; // pointer to control array of void pointers for action
93 static volatile Int_t fgXAnb; // size of array above
94 static volatile Int_t fgXArt; // return XA flag
95 static Long_t fgMainId; // thread id of main thread
96 static TThread *fgMain; // pointer to chain of TThread's
97 static TMutex *fgMainMutex; // mutex to protect chain of threads
98 static TMutex *fgXActMutex; // mutex to protect XAction
99 static TCondition *fgXActCondi; // condition for XAction
101 // Private Member functions
102 void Constructor();
103 void SetComment(const char *txt = nullptr)
104 { fComment[0] = 0; if (txt) { strncpy(fComment, txt, 99); fComment[99] = 0; } }
105 void DoError(Int_t level, const char *location, const char *fmt, va_list va) const;
106 void ErrorHandler(int level, const char *location, const char *fmt, va_list ap) const;
107 static void Init();
108 static void *Function(void *ptr);
109 static Int_t XARequest(const char *xact, Int_t nb, void **ar, Int_t *iret);
110 static void AfterCancel(TThread *th);
111 static void **GetTls(Int_t k);
113 TThread(const TThread&) = delete;
114 TThread& operator=(const TThread&) = delete;
117 TThread(VoidRtnFunc_t fn, void *arg = nullptr, EPriority pri = kNormalPriority);
118 TThread(VoidFunc_t fn, void *arg = nullptr, EPriority pri = kNormalPriority);
119 TThread(const char *thname, VoidRtnFunc_t fn, void *arg = nullptr, EPriority pri = kNormalPriority);
120 TThread(const char *thname, VoidFunc_t fn, void *arg = nullptr, EPriority pri = kNormalPriority);
121 TThread(Long_t id = 0);
122 virtual ~TThread();
124 Int_t Kill();
125 Int_t Run(void *arg = nullptr, const int affinity = -1);
126 void SetPriority(EPriority pri);
127 void Delete(Option_t *option="") { TObject::Delete(option); }
128 EPriority GetPriority() const { return fPriority; }
129 EState GetState() const { return fState; }
130 Long_t GetId() const { return fId; }
131 static void Ps();
132 static void ps() { Ps(); }
134 static void Initialize();
135 static Bool_t IsInitialized();
137 Long_t Join(void **ret = nullptr);
138 static Long_t Join(Long_t id, void **ret = nullptr);
140 static Int_t Exit(void *ret = nullptr);
141 static Int_t Exists();
142 static TThread *GetThread(Long_t id);
143 static TThread *GetThread(const char *name);
145 static Int_t Lock(); //User's lock of main mutex
146 static Int_t TryLock(); //User's try lock of main mutex
147 static Int_t UnLock(); //User's unlock of main mutex
148 static TThread *Self();
149 static Long_t SelfId();
150 static Int_t Sleep(ULong_t secs, ULong_t nanos = 0);
151 static Int_t GetTime(ULong_t *absSec, ULong_t *absNanoSec);
153 static Int_t Delete(TThread *&th);
154 static void **Tsd(void *dflt, Int_t k);
156 // Cancellation
157 // there are two types of TThread cancellation:
158 // DEFERRED - Cancellation only in user provided cancel-points
159 // ASYNCHRONOUS - In any point
160 // DEFERRED is more safe, it is DEFAULT.
161 static Int_t SetCancelOn();
162 static Int_t SetCancelOff();
164 static Int_t SetCancelDeferred();
165 static Int_t CancelPoint();
166 static Int_t Kill(Long_t id);
167 static Int_t Kill(const char *name);
168 static Int_t CleanUpPush(void *free, void *arg = nullptr);
169 static Int_t CleanUpPop(Int_t exe = 0);
170 static Int_t CleanUp();
172 // XActions
173 static void Printf(const char *fmt, ...) // format and print
174#if defined(__GNUC__) && !defined(__CINT__)
175 __attribute__((format(printf, 1, 2)))
177 ;
178 static void XAction();
180 ClassDef(TThread,0) // Thread class
185// //
186// TThreadCleaner //
187// //
198// //
199// TThreadTimer //
200// //
203class TThreadTimer : public TTimer {
205 // if this time is less or equal to kItimerResolution, TUnixSystem::DispatchOneEvent i
206 // can not exit and have its caller react to the other TTimer's actions (like the request
207 // to stop the event loop) until there is another type of event.
209 Bool_t Notify();
typedef void(GLAPIENTRYP _GLUfuncptr)(void)
int Int_t
Definition: RtypesCore.h:45
long Longptr_t
Definition: RtypesCore.h:82
unsigned long ULong_t
Definition: RtypesCore.h:55
long Long_t
Definition: RtypesCore.h:54
bool Bool_t
Definition: RtypesCore.h:63
const char Option_t
Definition: RtypesCore.h:66
#define ClassDef(name, id)
Definition: Rtypes.h:325
@ kItimerResolution
Definition: Rtypes.h:62
char name[80]
Definition: TGX11.cxx:110
#define free
Definition: civetweb.c:1539
Definition: TMutex.h:30
The TNamed class is the base class for all named ROOT classes.
Definition: TNamed.h:29
virtual void Delete(Option_t *option="")
Delete this object.
Definition: TObject.cxx:171
Call user clean up routines.
Definition: TThread.cxx:1230
TThreadTimer(Long_t ms=kItimerResolution+10)
Create thread timer.
Definition: TThread.cxx:1204
Bool_t Notify()
Periodically execute the TThread::XAction() method in the main thread.
Definition: TThread.cxx:1212
VoidRtnFunc_t fFcnRetn
Definition: TThread.h:84
static TThread * GetThread(Long_t id)
Static method to find a thread by id.
Definition: TThread.cxx:468
static Int_t CleanUpPop(Int_t exe=0)
Static method which pops thread cleanup method off stack.
Definition: TThread.cxx:702
static Int_t CancelPoint()
Static method to set a cancellation point.
Definition: TThread.cxx:681
static Int_t Sleep(ULong_t secs, ULong_t nanos=0)
Static method to sleep the calling thread.
Definition: TThread.cxx:755
static void **volatile fgXArr
Definition: TThread.h:92
static Int_t CleanUpPush(void *free, void *arg=nullptr)
Static method which pushes thread cleanup method on stack.
Definition: TThread.cxx:690
static Int_t TryLock()
Static method to try to lock the main thread mutex.
Definition: TThread.cxx:785
void SetPriority(EPriority pri)
Set thread priority.
Definition: TThread.cxx:460
static Int_t Exists()
Static method to check if threads exist.
Definition: TThread.cxx:444
static void ps()
Definition: TThread.h:132
TThread * fPrev
Definition: TThread.h:75
static void Ps()
Static method listing the existing threads.
Definition: TThread.cxx:848
TThread & operator=(const TThread &)=delete
char fComment[100]
Definition: TThread.h:88
static void ** GetTls(Int_t k)
Static method that initializes the TLS array of a thread and returns the reference to a given positio...
Definition: TThread.cxx:912
static TThreadImp * fgThreadImp
Definition: TThread.h:90
static Int_t UnLock()
Static method to unlock the main thread mutex.
Definition: TThread.cxx:793
Int_t Kill()
Kill this thread.
Definition: TThread.cxx:595
static TMutex * fgMainMutex
Definition: TThread.h:97
EState fState
Definition: TThread.h:78
EState fStateComing
Definition: TThread.h:79
static volatile Int_t fgXAnb
Definition: TThread.h:93
static Long_t fgMainId
Definition: TThread.h:95
EState GetState() const
Definition: TThread.h:129
Long_t Join(void **ret=nullptr)
Join this thread.
Definition: TThread.cxx:515
static void XAction()
Static method called via the thread timer to execute in the main thread certain commands.
Definition: TThread.cxx:1083
virtual ~TThread()
Cleanup the thread.
Definition: TThread.cxx:395
EPriority GetPriority() const
Definition: TThread.h:128
Bool_t fDetached
Definition: TThread.h:82
static Int_t SetCancelAsynchronous()
Static method to set the cancellation response type of the calling thread to asynchronous,...
Definition: TThread.cxx:662
static Int_t CleanUp()
Static method to cleanup the calling thread.
Definition: TThread.cxx:713
void ErrorHandler(int level, const char *location, const char *fmt, va_list ap) const
Thread specific error handler function.
Definition: TThread.cxx:968
static Int_t GetTime(ULong_t *absSec, ULong_t *absNanoSec)
Static method to get the current time.
Definition: TThread.cxx:766
static Long_t SelfId()
Static method returning the id for the current thread.
Definition: TThread.cxx:554
void Constructor()
Common thread constructor.
Definition: TThread.cxx:369
static Int_t SetCancelOn()
Static method to turn on thread cancellation.
Definition: TThread.cxx:652
static void ** Tsd(void *dflt, Int_t k)
Static method returning a pointer to thread specific data container of the calling thread.
Definition: TThread.cxx:899
void DoError(Int_t level, const char *location, const char *fmt, va_list va) const
Interface to ErrorHandler.
Definition: TThread.cxx:1012
Long_t fId
Definition: TThread.h:80
Bool_t fNamed
Definition: TThread.h:83
Int_t Run(void *arg=nullptr, const int affinity=-1)
Start the thread.
Definition: TThread.cxx:571
static volatile Int_t fgXArt
Definition: TThread.h:94
void SetComment(const char *txt=nullptr)
Definition: TThread.h:103
Long_t GetId() const
Definition: TThread.h:130
static Int_t XARequest(const char *xact, Int_t nb, void **ar, Int_t *iret)
Static method used to allow commands to be executed by the main thread.
Definition: TThread.cxx:1033
static std::atomic< char * > volatile fgXAct
Definition: TThread.h:91
VoidFunc_t fFcnVoid
Definition: TThread.h:85
static void * Function(void *ptr)
Static method which is called by the system thread function and which in turn calls the actual user f...
Definition: TThread.cxx:802
EPriority fPriority
Definition: TThread.h:77
static void Printf(const char *fmt,...)
Static method providing a thread safe printf. Appends a newline.
Definition: TThread.cxx:929
static Int_t Lock()
Static method to lock the main thread mutex.
Definition: TThread.cxx:777
void(* VoidFunc_t)(void *)
Definition: TThread.h:53
Definition: TThread.h:61
@ kRunningState
Definition: TThread.h:64
@ kNewState
Definition: TThread.h:63
@ kCanceledState
Definition: TThread.h:69
@ kCancelingState
Definition: TThread.h:68
@ kFinishedState
Definition: TThread.h:67
@ kTerminatedState
Definition: TThread.h:65
@ kDeletingState
Definition: TThread.h:70
@ kInvalidState
Definition: TThread.h:62
static Int_t SetCancelOff()
Static method to turn off thread cancellation.
Definition: TThread.cxx:643
static void Init()
Initialize global state and variables once.
Definition: TThread.cxx:319
static Int_t SetCancelDeferred()
Static method to set the cancellation response type of the calling thread to deferred,...
Definition: TThread.cxx:672
Longptr_t fHandle
Definition: TThread.h:81
static void AfterCancel(TThread *th)
Static method which is called after the thread has been canceled.
Definition: TThread.cxx:734
static TThread * fgMain
Definition: TThread.h:96
static TMutex * fgXActMutex
Definition: TThread.h:98
Definition: TThread.h:55
@ kHighPriority
Definition: TThread.h:58
@ kLowPriority
Definition: TThread.h:56
@ kNormalPriority
Definition: TThread.h:57
static Bool_t IsInitialized()
Return true, if the TThread objects have been initialize.
Definition: TThread.cxx:309
static TThread * Self()
Static method returning pointer to current thread.
Definition: TThread.cxx:500
static Int_t Exit(void *ret=nullptr)
Static method which terminates the execution of the calling thread.
Definition: TThread.cxx:747
static void Initialize()
Initialize the Thread package.
Definition: TThread.cxx:300
void * fClean
Definition: TThread.h:87
static TCondition * fgXActCondi
Definition: TThread.h:99
void Delete(Option_t *option="")
Delete this object.
Definition: TThread.h:127
TThread(const TThread &)=delete
TThread ** fHolder
Definition: TThread.h:76
TThread * fNext
Definition: TThread.h:74
void *(* VoidRtnFunc_t)(void *)
Definition: TThread.h:52
void * fThreadArg
Definition: TThread.h:86
Handles synchronous and a-synchronous timer events.
Definition: TTimer.h:51
static constexpr double ms