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 */
81static UBool gAutoCleanRegistered = FALSE;
82
83static void ucln_atexit_handler()
84{
85    UCLN_CLEAN_ME_UP;
86}
87
88static void ucln_registerAutomaticCleanup()
89{
90    if(!gAutoCleanRegistered) {
91        gAutoCleanRegistered = TRUE;
92        atexit(&ucln_atexit_handler);
93    }
94}
95
96static 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 */
106U_CAPI void U_EXPORT2 UCLN_FINI (void);
107
108U_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 */
136BOOL 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)) */
169static void ucln_destructor()   __attribute__((destructor)) ;
170
171static 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
183