icuSources/common/ucln_imp.h

   1 /*
   2 ******************************************************************************
   3 *                                                                            *
   4 * Copyright (C) 2009, International Business Machines                   *
   5 *                Corporation and others. All Rights Reserved.                *
   6 *                                                                            *
   7 ******************************************************************************
   8 *   file name:  ucln_imp.h
   9 *   encoding:   US-ASCII
  10 *   tab size:   8 (not used)
  11 *   indentation:4
  12 *
  13 *   This file contains the platform specific implementation of per-library cleanup.
  14 *
  15 */
  16
  17
  18 #ifndef __UCLN_IMP_H__
  19 #define __UCLN_IMP_H__
  20
  21 #include "ucln.h"
  22 #include <stdlib.h>
  23
  24 /**
  25  * Auto cleanup of ICU libraries
  26  * There are several methods in per library cleanup of icu libraries:
  27  * 1) Compiler/Platform based cleanup:
  28  *   a) Windows MSVC uses DllMain()
  29  *   b) GCC uses destructor function attribute
  30  *   c) Sun Studio, AIX VA, and HP-UX aCC uses a linker option to set the exit function
  31  * 2) Using atexit()
  32  * 3) Implementing own automatic cleanup functions
  33  *
  34  * For option 1, ensure that UCLN_NO_AUTO_CLEANUP is set to 0 by using --enable-auto-cleanup
  35  * configure option or by setting UCLN_NO_AUTO_CLEANUP to 0 in pwin32.h (For Visual Studio
  36  * solution file builds)
  37  * For option 2, follow option 1 and also define UCLN_AUTO_ATEXIT
  38  * For option 3, follow option 1 and also define UCLN_AUTO_LOCAL (see below for more information)
  39  */
  40
  41 #if !UCLN_NO_AUTO_CLEANUP
  42
  43 /*
  44  * The following declarations are for when UCLN_AUTO_LOCAL or UCLN_AUTO_ATEXIT
  45  * are defined. They are commented out because they are static and will be defined
  46  * later. The information is still here to provide some guidance for the developer
  47  * who chooses to use UCLN_AUTO_LOCAL.
  48  */
  49 /**
  50  * Give the library an opportunity to register an automatic cleanup.
  51  * This may be called more than once.
  52  */
  53 /*static void ucln_registerAutomaticCleanup();*/
  54 /**
  55  * Unregister an automatic cleanup, if possible. Called from cleanup.
  56  */
  57 /*static void ucln_unRegisterAutomaticCleanup();*/
  58
  59 /* ------------ automatic cleanup: registration. Choose ONE ------- */
  60 #if defined(UCLN_AUTO_LOCAL)
  61 /* To use:
  62  *  1. define UCLN_AUTO_LOCAL,
  63  *  2. create ucln_local_hook.c containing implementations of
  64  *           static void ucln_registerAutomaticCleanup()
  65  *           static void ucln_unRegisterAutomaticCleanup()
  66  */
  67 #include "ucln_local_hook.c"
  68
  69 #elif defined(UCLN_AUTO_ATEXIT)
  70 /*
  71  * Use the ANSI C 'atexit' function. Note that this mechanism does not
  72  * guarantee the order of cleanup relative to other users of ICU!
  73  */
  74 static UBool gAutoCleanRegistered = FALSE;
  75
  76 static void ucln_atexit_handler()
  77 {
  78     ucln_cleanupOne(UCLN_TYPE);
  79 }
  80
  81 static void ucln_registerAutomaticCleanup()
  82 {
  83     if(!gAutoCleanRegistered) {
  84         gAutoCleanRegistered = TRUE;
  85         atexit(&ucln_atexit_handler);
  86     }
  87 }
  88
  89 static void ucln_unRegisterAutomaticCleanup () {
  90 }
  91 /* ------------end of automatic cleanup: registration. ------- */
  92
  93 #elif defined (UCLN_FINI)
  94 /**
  95  * If UCLN_FINI is defined, it is the (versioned, etc) name of a cleanup
  96  * entrypoint. Add a stub to call ucln_cleanupOne
  97  * Used on AIX, Solaris, and HP-UX
  98  */
  99 U_CAPI void U_EXPORT2 UCLN_FINI (void);
 100
 101 U_CAPI void U_EXPORT2 UCLN_FINI ()
 102 {
 103     /* This function must be defined, if UCLN_FINI is defined, else link error. */
 104      ucln_cleanupOne(UCLN_TYPE);
 105 }
 106 #elif defined(__GNUC__)
 107 /* GCC - use __attribute((destructor)) */
 108 static void ucln_destructor()   __attribute__((destructor)) ;
 109
 110 static void ucln_destructor()
 111 {
 112     ucln_cleanupOne(UCLN_TYPE);
 113 }
 114
 115 /* Windows: DllMain */
 116 #elif defined (U_WINDOWS)
 117 /*
 118  * ICU's own DllMain.
 119  */
 120
 121 /* these are from putil.c */
 122 /* READ READ READ READ!    Are you getting compilation errors from windows.h?
 123           Any source file which includes this (ucln_imp.h) header MUST
 124           be defined with language extensions ON. */
 125 #   define WIN32_LEAN_AND_MEAN
 126 #   define VC_EXTRALEAN
 127 #   define NOUSER
 128 #   define NOSERVICE
 129 #   define NOIME
 130 #   define NOMCX
 131 #   include <windows.h>
 132 /*
 133  * This is a stub DllMain function with icu specific process handling code.
 134  */
 135 BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
 136 {
 137     BOOL status = TRUE;
 138
 139     switch(fdwReason) {
 140         case DLL_PROCESS_ATTACH:
 141              /* ICU does not trap process attach, but must pass these through properly. */
 142             /* ICU specific process attach could go here */
 143             break;
 144
 145         case DLL_PROCESS_DETACH:
 146             /* Here is the one we actually care about. */
 147
 148             ucln_cleanupOne(UCLN_TYPE);
 149
 150             break;
 151
 152         case DLL_THREAD_ATTACH:
 153             /* ICU does not trap thread attach, but must pass these through properly. */
 154             /* ICU specific thread attach could go here */
 155             break;
 156
 157         case DLL_THREAD_DETACH:
 158             /* ICU does not trap thread detach, but must pass these through properly. */
 159             /* ICU specific thread detach could go here */
 160             break;
 161
 162     }
 163     return status;
 164 }
 165 #endif
 166
 167 #endif /* UCLN_NO_AUTO_CLEANUP */
 168
 169 #else
 170 #error This file can only be included once.
 171 #endif