1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 ******************************************************************************
5 * Copyright (C) 2001-2014, International Business Machines
6 * Corporation and others. All Rights Reserved.
7 ******************************************************************************
8 * file name: ucln_cmn.cpp
9 * encoding: UTF-8
10 * tab size: 8 (not used)
11 * indentation:4
12 *
13 * created on: 2001July05
14 * created by: George Rhoten
15 */
16
17 #include "unicode/utypes.h"
18 #include "unicode/uclean.h"
19 #include "cmemory.h"
20 #include "mutex.h"
21 #include "uassert.h"
22 #include "ucln.h"
23 #include "ucln_cmn.h"
24 #include "utracimp.h"
25 #include "umutex.h"
26
27 /** Auto-client for UCLN_COMMON **/
28 #define UCLN_TYPE_IS_COMMON
29 #include "ucln_imp.h"
30
31 static cleanupFunc *gCommonCleanupFunctions[UCLN_COMMON_COUNT];
32 static cleanupFunc *gLibCleanupFunctions[UCLN_COMMON];
33
34
35 /************************************************
36 The cleanup order is important in this function.
37 Please be sure that you have read ucln.h
38 ************************************************/
39 U_CAPI void U_EXPORT2
u_cleanup(void)40 u_cleanup(void)
41 {
42 UTRACE_ENTRY_OC(UTRACE_U_CLEANUP);
43 icu::umtx_lock(NULL); /* Force a memory barrier, so that we are sure to see */
44 icu::umtx_unlock(NULL); /* all state left around by any other threads. */
45
46 ucln_lib_cleanup();
47
48 cmemory_cleanup(); /* undo any heap functions set by u_setMemoryFunctions(). */
49 UTRACE_EXIT(); /* Must be before utrace_cleanup(), which turns off tracing. */
50 /*#if U_ENABLE_TRACING*/
51 utrace_cleanup();
52 /*#endif*/
53 }
54
ucln_cleanupOne(ECleanupLibraryType libType)55 U_CAPI void U_EXPORT2 ucln_cleanupOne(ECleanupLibraryType libType)
56 {
57 if (gLibCleanupFunctions[libType])
58 {
59 gLibCleanupFunctions[libType]();
60 gLibCleanupFunctions[libType] = NULL;
61 }
62 }
63
64 U_CFUNC void
ucln_common_registerCleanup(ECleanupCommonType type,cleanupFunc * func)65 ucln_common_registerCleanup(ECleanupCommonType type,
66 cleanupFunc *func)
67 {
68 // Thread safety messiness: From ticket 10295, calls to registerCleanup() may occur
69 // concurrently. Although such cases should be storing the same value, they raise errors
70 // from the thread sanity checker. Doing the store within a mutex avoids those.
71 // BUT that can trigger a recursive entry into std::call_once() in umutex.cpp when this code,
72 // running from the call_once function, tries to grab the ICU global mutex, which
73 // re-enters the mutex init path. So, work-around by special casing UCLN_COMMON_MUTEX, not
74 // using the ICU global mutex for it.
75 //
76 // No other point in ICU uses std::call_once().
77
78 U_ASSERT(UCLN_COMMON_START < type && type < UCLN_COMMON_COUNT);
79 if (type == UCLN_COMMON_MUTEX) {
80 gCommonCleanupFunctions[type] = func;
81 } else if (UCLN_COMMON_START < type && type < UCLN_COMMON_COUNT) {
82 icu::Mutex m; // See ticket 10295 for discussion.
83 gCommonCleanupFunctions[type] = func;
84 }
85 #if !UCLN_NO_AUTO_CLEANUP && (defined(UCLN_AUTO_ATEXIT) || defined(UCLN_AUTO_LOCAL))
86 ucln_registerAutomaticCleanup();
87 #endif
88 }
89
90 // Note: ucln_registerCleanup() is called with the ICU global mutex locked.
91 // Be aware if adding anything to the function.
92 // See ticket 10295 for discussion.
93
94 U_CAPI void U_EXPORT2
ucln_registerCleanup(ECleanupLibraryType type,cleanupFunc * func)95 ucln_registerCleanup(ECleanupLibraryType type,
96 cleanupFunc *func)
97 {
98 U_ASSERT(UCLN_START < type && type < UCLN_COMMON);
99 if (UCLN_START < type && type < UCLN_COMMON)
100 {
101 gLibCleanupFunctions[type] = func;
102 }
103 }
104
ucln_lib_cleanup(void)105 U_CFUNC UBool ucln_lib_cleanup(void) {
106 int32_t libType = UCLN_START;
107 int32_t commonFunc = UCLN_COMMON_START;
108
109 for (libType++; libType<UCLN_COMMON; libType++) {
110 ucln_cleanupOne(static_cast<ECleanupLibraryType>(libType));
111 }
112
113 for (commonFunc++; commonFunc<UCLN_COMMON_COUNT; commonFunc++) {
114 if (gCommonCleanupFunctions[commonFunc])
115 {
116 gCommonCleanupFunctions[commonFunc]();
117 gCommonCleanupFunctions[commonFunc] = NULL;
118 }
119 }
120 #if !UCLN_NO_AUTO_CLEANUP && (defined(UCLN_AUTO_ATEXIT) || defined(UCLN_AUTO_LOCAL))
121 ucln_unRegisterAutomaticCleanup();
122 #endif
123 return true;
124 }
125