1 /*
2 ******************************************************************************
3 *
4 * Copyright (C) 1997-2003, International Business Machines
5 * Corporation and others. All Rights Reserved.
6 *
7 ******************************************************************************
8 */
9 //----------------------------------------------------------------------------
10 // File: mutex.h
11 //
12 // Lightweight C++ wrapper for umtx_ C mutex functions
13 //
14 // Author: Alan Liu 1/31/97
15 // History:
16 // 06/04/97 helena Updated setImplementation as per feedback from 5/21 drop.
17 // 04/07/1999 srl refocused as a thin wrapper
18 //
19 //----------------------------------------------------------------------------
20 #ifndef MUTEX_H
21 #define MUTEX_H
22
23 #include "unicode/utypes.h"
24 #include "unicode/uobject.h"
25 #include "umutex.h"
26
27 U_NAMESPACE_BEGIN
28
29 //----------------------------------------------------------------------------
30 // Code within that accesses shared static or global data should
31 // should instantiate a Mutex object while doing so. You should make your own
32 // private mutex where possible.
33
34 // For example:
35 //
36 // UMTX myMutex;
37 //
38 // int InitializeMyMutex()
39 // {
40 // umtx_init( &myMutex );
41 // return 0;
42 // }
43 //
44 // static int initializeMyMutex = InitializeMyMutex();
45 //
46 // void Function(int arg1, int arg2)
47 // {
48 // static Object* foo; // Shared read-write object
49 // Mutex mutex(&myMutex); // or no args for the global lock
50 // foo->Method();
51 // // When 'mutex' goes out of scope and gets destroyed here, the lock is released
52 // }
53 //
54 // Note: Do NOT use the form 'Mutex mutex();' as that merely forward-declares a function
55 // returning a Mutex. This is a common mistake which silently slips through the
56 // compiler!!
57 //
58
59 class U_COMMON_API Mutex : public UMemory {
60 public:
61 inline Mutex(UMTX *mutex = NULL);
62 inline ~Mutex();
63
64 private:
65 UMTX *fMutex;
66
67 Mutex(const Mutex &other); // forbid copying of this class
68 Mutex &operator=(const Mutex &other); // forbid copying of this class
69 };
70
Mutex(UMTX * mutex)71 inline Mutex::Mutex(UMTX *mutex)
72 : fMutex(mutex)
73 {
74 umtx_lock(fMutex);
75 }
76
~Mutex()77 inline Mutex::~Mutex()
78 {
79 umtx_unlock(fMutex);
80 }
81
82 U_NAMESPACE_END
83
84 #endif //_MUTEX_
85 //eof
86