icuSources/common/ucln_imp.h

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4 ******************************************************************************
   5 *
   6 * Copyright (C) 2009-2011, International Business Machines
   7 *                Corporation and others. All Rights Reserved.
   8 *
   9 ******************************************************************************
  10 *   file name:  ucln_imp.h
  11 *   encoding:   UTF-8
  12 *   tab size:   8 (not used)
  13 *   indentation:4
  14 *
  15 *   This file contains the platform specific implementation of per-library cleanup.
  16 *
  17 */
  18
  19
  20 #ifndef __UCLN_IMP_H__
  21 #define __UCLN_IMP_H__
  22
  23 #include "ucln.h"
  24 #include <stdlib.h>
  25
  26 /**
  27  * Auto cleanup of ICU libraries
  28  * There are several methods in per library cleanup of icu libraries:
  29  * 1) Compiler/Platform based cleanup:
  30  *   a) Windows MSVC uses DllMain()
  31  *   b) GCC uses destructor function attribute
  32  *   c) Sun Studio, AIX VA, and HP-UX aCC uses a linker option to set the exit function
  33  * 2) Using atexit()
  34  * 3) Implementing own automatic cleanup functions
  35  *
  36  * For option 1, ensure that UCLN_NO_AUTO_CLEANUP is set to 0 by using --enable-auto-cleanup
  37  * configure option or by otherwise setting UCLN_NO_AUTO_CLEANUP to 0
  38  * For option 2, follow option 1 and also define UCLN_AUTO_ATEXIT
  39  * For option 3, follow option 1 and also define UCLN_AUTO_LOCAL (see below for more information)
  40  */
  41
  42 #if !UCLN_NO_AUTO_CLEANUP
  43
  44 /*
  45  * The following declarations are for when UCLN_AUTO_LOCAL or UCLN_AUTO_ATEXIT
  46  * are defined. They are commented out because they are static and will be defined
  47  * later. The information is still here to provide some guidance for the developer
  48  * who chooses to use UCLN_AUTO_LOCAL.
  49  */
  50 /**
  51  * Give the library an opportunity to register an automatic cleanup.
  52  * This may be called more than once.
  53  */
  54 /*static void ucln_registerAutomaticCleanup();*/
  55 /**
  56  * Unregister an automatic cleanup, if possible. Called from cleanup.
  57  */
  58 /*static void ucln_unRegisterAutomaticCleanup();*/
  59
  60 #ifdef UCLN_TYPE_IS_COMMON
  61 #   define UCLN_CLEAN_ME_UP u_cleanup()
  62 #else
  63 #   define UCLN_CLEAN_ME_UP ucln_cleanupOne(UCLN_TYPE)
  64 #endif
  65
  66 /* ------------ automatic cleanup: registration. Choose ONE ------- */
  67 #if defined(UCLN_AUTO_LOCAL)
  68 /* To use:
  69  *  1. define UCLN_AUTO_LOCAL,
  70  *  2. create ucln_local_hook.c containing implementations of
  71  *           static void ucln_registerAutomaticCleanup()
  72  *           static void ucln_unRegisterAutomaticCleanup()
  73  */
  74 #include "ucln_local_hook.c"
  75
  76 #elif defined(UCLN_AUTO_ATEXIT)
  77 /*
  78  * Use the ANSI C 'atexit' function. Note that this mechanism does not
  79  * guarantee the order of cleanup relative to other users of ICU!
  80  */
  81 static UBool gAutoCleanRegistered = FALSE;
  82
  83 static void ucln_atexit_handler()
  84 {
  85     UCLN_CLEAN_ME_UP;
  86 }
  87
  88 static void ucln_registerAutomaticCleanup()
  89 {
  90     if(!gAutoCleanRegistered) {
  91         gAutoCleanRegistered = TRUE;
  92         atexit(&ucln_atexit_handler);
  93     }
  94 }
  95
  96 static void ucln_unRegisterAutomaticCleanup () {
  97 }
  98 /* ------------end of automatic cleanup: registration. ------- */
  99
 100 #elif defined (UCLN_FINI)
 101 /**
 102  * If UCLN_FINI is defined, it is the (versioned, etc) name of a cleanup
 103  * entrypoint. Add a stub to call ucln_cleanupOne
 104  * Used on AIX, Solaris, and HP-UX
 105  */
 106 U_CAPI void U_EXPORT2 UCLN_FINI (void);
 107
 108 U_CAPI void U_EXPORT2 UCLN_FINI ()
 109 {
 110     /* This function must be defined, if UCLN_FINI is defined, else link error. */
 111      UCLN_CLEAN_ME_UP;
 112 }
 113
 114 /* Windows: DllMain */
 115 #elif U_PLATFORM_HAS_WIN32_API
 116 /*
 117  * ICU's own DllMain.
 118  */
 119
 120 /* these are from putil.c */
 121 /* READ READ READ READ!    Are you getting compilation errors from windows.h?
 122           Any source file which includes this (ucln_imp.h) header MUST
 123           be defined with language extensions ON. */
 124 #ifndef WIN32_LEAN_AND_MEAN
 125 #   define WIN32_LEAN_AND_MEAN
 126 #endif
 127 #   define VC_EXTRALEAN
 128 #   define NOUSER
 129 #   define NOSERVICE
 130 #   define NOIME
 131 #   define NOMCX
 132 #   include <windows.h>
 133 /*
 134  * This is a stub DllMain function with icu specific process handling code.
 135  */
 136 BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
 137 {
 138     BOOL status = TRUE;
 139
 140     switch(fdwReason) {
 141         case DLL_PROCESS_ATTACH:
 142              /* ICU does not trap process attach, but must pass these through properly. */
 143             /* ICU specific process attach could go here */
 144             break;
 145
 146         case DLL_PROCESS_DETACH:
 147             /* Here is the one we actually care about. */
 148
 149             UCLN_CLEAN_ME_UP;
 150
 151             break;
 152
 153         case DLL_THREAD_ATTACH:
 154             /* ICU does not trap thread attach, but must pass these through properly. */
 155             /* ICU specific thread attach could go here */
 156             break;
 157
 158         case DLL_THREAD_DETACH:
 159             /* ICU does not trap thread detach, but must pass these through properly. */
 160             /* ICU specific thread detach could go here */
 161             break;
 162
 163     }
 164     return status;
 165 }
 166
 167 #elif defined(__GNUC__)
 168 /* GCC - use __attribute((destructor)) */
 169 static void ucln_destructor()   __attribute__((destructor)) ;
 170
 171 static void ucln_destructor()
 172 {
 173     UCLN_CLEAN_ME_UP;
 174 }
 175
 176 #endif
 177
 178 #endif /* UCLN_NO_AUTO_CLEANUP */
 179
 180 #else
 181 #error This file can only be included once.
 182 #endif