icuSources/common/ucln.h

   1 /*
   2 ******************************************************************************
   3 *
   4 * Copyright (C) 2001-2011, International Business Machines
   5 *                Corporation and others. All Rights Reserved.
   6 *
   7 ******************************************************************************
   8 *   file name:  ucln.h
   9 *   encoding:   US-ASCII
  10 *   tab size:   8 (not used)
  11 *   indentation:4
  12 *
  13 *   created on: 2001July05
  14 *   created by: George Rhoten
  15 */
  16
  17 #ifndef __UCLN_H__
  18 #define __UCLN_H__
  19
  20 #include "unicode/utypes.h"
  21 #include "umutex.h"
  22
  23 /** These are the functions used to register a library's memory cleanup
  24  * functions.  Each library should define a single library register function
  25  * to call this API.  In the i18n library, it is ucln_i18n_registerCleanup().
  26  *
  27  * None of the cleanup functions should use a mutex to clean up an API's
  28  * allocated memory because a cleanup function is not meant to be thread safe,
  29  * and plenty of data cannot be reference counted in order to make sure that
  30  * no one else needs the allocated data.
  31  *
  32  * In order to make a cleanup function get called when u_cleanup is called,
  33  * You should add your function to the library specific cleanup function.
  34  * If the cleanup function is not in the common library, the code that
  35  * allocates the memory should call the library specific cleanup function.
  36  * For instance, in the i18n library, any memory allocated statically must
  37  * call ucln_i18n_registerCleanup() from the ucln_in.h header.  These library
  38  * cleanup functions are needed in order to prevent a circular dependency
  39  * between the common library and any other library.
  40  *
  41  * The order of the cleanup is very important.  In general, an API that
  42  * depends on a second API should be cleaned up before the second API.
  43  * For instance, the default converter in ustring depends upon the converter
  44  * API.  So the default converter should be closed before the converter API
  45  * has its cache flushed.  This will prevent any memory leaks due to
  46  * reference counting.
  47  *
  48  * Please see common/ucln_cmn.{h,c} and i18n/ucln_in.{h,c} for examples.
  49  */
  50
  51 /**
  52  * Data Type for cleanup function selector. These roughly correspond to libraries.
  53  */
  54 typedef enum ECleanupLibraryType {
  55     UCLN_START = -1,
  56     UCLN_UPLUG,     /* ICU plugins */
  57     UCLN_CUSTOM,    /* Custom is for anyone else. */
  58     UCLN_CTESTFW,
  59     UCLN_TOOLUTIL,
  60     UCLN_LAYOUTEX,
  61     UCLN_LAYOUT,
  62     UCLN_IO,
  63     UCLN_I18N,
  64     UCLN_COMMON /* This must be the last one to cleanup. */
  65 } ECleanupLibraryType;
  66
  67 /**
  68  * Data type for cleanup function pointer
  69  */
  70 U_CDECL_BEGIN
  71 typedef UBool U_CALLCONV cleanupFunc(void);
  72 U_CDECL_END
  73
  74 /**
  75  * Register a cleanup function
  76  * @param type which library to register for.
  77  * @param func the function pointer
  78  */
  79 U_CAPI void U_EXPORT2 ucln_registerCleanup(ECleanupLibraryType type,
  80                                            cleanupFunc *func);
  81
  82 /**
  83  * Request cleanup for one specific library.
  84  * Not thread safe.
  85  * @param type which library to cleanup
  86  */
  87 U_CAPI void U_EXPORT2 ucln_cleanupOne(ECleanupLibraryType type);
  88
  89 /* ucln_cmn.c variables shared with uinit.c */
  90 U_CDECL_BEGIN
  91
  92 extern UBool gICUInitialized;
  93 extern UMTX  gICUInitMutex;
  94
  95 U_CDECL_END
  96
  97 #endif