icuSources/common/ucln.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) 2001-2013, International Business Machines
   7 *                Corporation and others. All Rights Reserved.
   8 *
   9 ******************************************************************************
  10 *   file name:  ucln.h
  11 *   encoding:   UTF-8
  12 *   tab size:   8 (not used)
  13 *   indentation:4
  14 *
  15 *   created on: 2001July05
  16 *   created by: George Rhoten
  17 */
  18
  19 #ifndef __UCLN_H__
  20 #define __UCLN_H__
  21
  22 #include "unicode/utypes.h"
  23
  24 /** These are the functions used to register a library's memory cleanup
  25  * functions.  Each library should define a single library register function
  26  * to call this API.  In the i18n library, it is ucln_i18n_registerCleanup().
  27  *
  28  * None of the cleanup functions should use a mutex to clean up an API's
  29  * allocated memory because a cleanup function is not meant to be thread safe,
  30  * and plenty of data cannot be reference counted in order to make sure that
  31  * no one else needs the allocated data.
  32  *
  33  * In order to make a cleanup function get called when u_cleanup is called,
  34  * You should add your function to the library specific cleanup function.
  35  * If the cleanup function is not in the common library, the code that
  36  * allocates the memory should call the library specific cleanup function.
  37  * For instance, in the i18n library, any memory allocated statically must
  38  * call ucln_i18n_registerCleanup() from the ucln_in.h header.  These library
  39  * cleanup functions are needed in order to prevent a circular dependency
  40  * between the common library and any other library.
  41  *
  42  * The order of the cleanup is very important.  In general, an API that
  43  * depends on a second API should be cleaned up before the second API.
  44  * For instance, the default converter in ustring depends upon the converter
  45  * API.  So the default converter should be closed before the converter API
  46  * has its cache flushed.  This will prevent any memory leaks due to
  47  * reference counting.
  48  *
  49  * Please see common/ucln_cmn.{h,c} and i18n/ucln_in.{h,c} for examples.
  50  */
  51
  52 /**
  53  * Data Type for cleanup function selector. These roughly correspond to libraries.
  54  */
  55 typedef enum ECleanupLibraryType {
  56     UCLN_START = -1,
  57     UCLN_UPLUG,     /* ICU plugins */
  58     UCLN_CUSTOM,    /* Custom is for anyone else. */
  59     UCLN_CTESTFW,
  60     UCLN_TOOLUTIL,
  61     UCLN_LAYOUTEX,
  62     UCLN_LAYOUT,
  63     UCLN_IO,
  64     UCLN_I18N,
  65     UCLN_COMMON /* This must be the last one to cleanup. */
  66 } ECleanupLibraryType;
  67
  68 /**
  69  * Data type for cleanup function pointer
  70  */
  71 U_CDECL_BEGIN
  72 typedef UBool U_CALLCONV cleanupFunc(void);
  73 typedef void U_CALLCONV initFunc(UErrorCode *);
  74 U_CDECL_END
  75
  76 /**
  77  * Register a cleanup function
  78  * @param type which library to register for.
  79  * @param func the function pointer
  80  */
  81 U_CAPI void U_EXPORT2 ucln_registerCleanup(ECleanupLibraryType type,
  82                                            cleanupFunc *func);
  83
  84 /**
  85  * Request cleanup for one specific library.
  86  * Not thread safe.
  87  * @param type which library to cleanup
  88  */
  89 U_CAPI void U_EXPORT2 ucln_cleanupOne(ECleanupLibraryType type);
  90
  91 #endif