Logo ROOT   6.12/07
Reference Guide
TRWMutexImp.cxx
Go to the documentation of this file.
1 // @(#)root/thread:$Id$
2 // Author: Fons Rademakers 26/06/97
3 
4 /*************************************************************************
5  * Copyright (C) 1995-2017, 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 //////////////////////////////////////////////////////////////////////////
13 // //
14 // TRWMutexImp //
15 // //
16 // This class implements the TVirtualRWMutex interface, //
17 // based on TRWSpinLock. //
18 // //
19 //////////////////////////////////////////////////////////////////////////
20 
21 #include "TRWMutexImp.h"
22 #include "ROOT/TSpinMutex.hxx"
23 #include "TMutex.h"
24 
25 namespace ROOT {
26 
27 ////////////////////////////////////////////////////////////////////////////////
28 /// Take the Read Lock of the mutex.
29 
30 template <typename MutexT, typename RecurseCountsT>
32 {
33  return fMutexImp.ReadLock();
34 }
35 
36 ////////////////////////////////////////////////////////////////////////////////
37 /// Take the Write Lock of the mutex.
38 
39 template <typename MutexT, typename RecurseCountsT>
41 {
42  return fMutexImp.WriteLock();
43 }
44 
45 ////////////////////////////////////////////////////////////////////////////////
46 /// Release the read lock of the mutex
47 
48 template <typename MutexT, typename RecurseCountsT>
49 void TRWMutexImp<MutexT, RecurseCountsT>::ReadUnLock(TVirtualRWMutex::Hint_t *hint)
50 {
51  fMutexImp.ReadUnLock(hint);
52 }
53 
54 ////////////////////////////////////////////////////////////////////////////////
55 /// Release the read lock of the mutex
56 
57 template <typename MutexT, typename RecurseCountsT>
58 void TRWMutexImp<MutexT, RecurseCountsT>::WriteUnLock(TVirtualRWMutex::Hint_t *hint)
59 {
60  fMutexImp.WriteUnLock(hint);
61 }
62 
63 ////////////////////////////////////////////////////////////////////////////////
64 /// Create mutex and return pointer to it.
65 
66 template <typename MutexT, typename RecurseCountsT>
68 {
69  return new TRWMutexImp();
70 }
71 
72 ////////////////////////////////////////////////////////////////////////////////
73 /// Restore the mutex state to `state`. This function must only be called while
74 /// the mutex is locked. Returns the DeltaState between now and the resulting
75 /// state (i.e. lock count before state), such that the difference can be
76 /// re-applied using `Apply()`.
77 /// In pseudo-code:
78 /// delta = current_lock_count - earlierState.lock_count;
79 /// current_lock_count -= delta;
80 /// return delta;
81 
82 template <typename MutexT, typename RecurseCountsT>
83 std::unique_ptr<TVirtualRWMutex::StateDelta>
85 {
86  return fMutexImp.Rewind(earlierState);
87 }
88 
89 ////////////////////////////////////////////////////////////////////////////////
90 /// Apply the mutex state delta.
91 /// In pseudo-code:
92 /// current_lock_count += delta;
93 
94 template <typename MutexT, typename RecurseCountsT>
95 void TRWMutexImp<MutexT, RecurseCountsT>::Apply(std::unique_ptr<TVirtualRWMutex::StateDelta> &&delta)
96 {
97  fMutexImp.Apply(std::move(delta));
98 }
99 
100 ////////////////////////////////////////////////////////////////////////////////
101 /// Get the mutex state *before* the current lock was taken. This function must
102 /// only be called while the mutex is locked.
103 
104 template <typename MutexT, typename RecurseCountsT>
105 std::unique_ptr<TVirtualRWMutex::State>
107 {
108  return fMutexImp.GetStateBefore();
109 }
110 
111 template class TRWMutexImp<TMutex>;
112 template class TRWMutexImp<ROOT::TSpinMutex>;
113 template class TRWMutexImp<std::mutex>;
116 
117 } // End of namespace ROOT
void Apply(std::unique_ptr< StateDelta > &&delta) override
Apply the mutex state delta.
Definition: TRWMutexImp.cxx:95
Namespace for new ROOT classes and functions.
Definition: StringConv.hxx:21
Hint_t * ReadLock() override
Take the Read Lock of the mutex.
Definition: TRWMutexImp.cxx:31
std::unique_ptr< State > GetStateBefore() override
Get the mutex state before the current lock was taken.
bool Bool_t
Definition: RtypesCore.h:59
Hint_t * WriteLock() override
Take the Write Lock of the mutex.
Definition: TRWMutexImp.cxx:40
void ReadUnLock(Hint_t *) override
Release the read lock of the mutex.
Definition: TRWMutexImp.cxx:49
void WriteUnLock(Hint_t *) override
Release the read lock of the mutex.
Definition: TRWMutexImp.cxx:58
Earlier lock state as returned by GetState() that can be passed to Restore()
TVirtualRWMutex * Factory(Bool_t=kFALSE) override
Create mutex and return pointer to it.
Definition: TRWMutexImp.cxx:67
std::unique_ptr< StateDelta > Rewind(const State &earlierState) override
Restore the mutex state to state.
Definition: TRWMutexImp.cxx:84