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      1 /*
      2 ******************************************************************************
      3 * Copyright (C) 2001-2012, International Business Machines
      4 *                Corporation and others. All Rights Reserved.
      5 ******************************************************************************
      6 *   file name:  uclean.h
      7 *   encoding:   US-ASCII
      8 *   tab size:   8 (not used)
      9 *   indentation:4
     10 *
     11 *   created on: 2001July05
     12 *   created by: George Rhoten
     13 */
     14 
     15 #ifndef __UCLEAN_H__
     16 #define __UCLEAN_H__
     17 
     18 #include "unicode/utypes.h"
     19 /**
     20  * \file
     21  * \brief C API: Initialize and clean up ICU
     22  */
     23 
     24 /**
     25  *  Initialize ICU.
     26  *
     27  *  Use of this function is optional.  It is OK to simply use ICU
     28  *  services and functions without first having initialized
     29  *  ICU by calling u_init().
     30  *
     31  *  u_init() will attempt to load some part of ICU's data, and is
     32  *  useful as a test for configuration or installation problems that
     33  *  leave the ICU data inaccessible.  A successful invocation of u_init()
     34  *  does not, however, guarantee that all ICU data is accessible.
     35  *
     36  *  Multiple calls to u_init() cause no harm, aside from the small amount
     37  *  of time required.
     38  *
     39  *  In old versions of ICU, u_init() was required in multi-threaded applications
     40  *  to ensure the thread safety of ICU.  u_init() is no longer needed for this purpose.
     41  *
     42  * @param status An ICU UErrorCode parameter. It must not be <code>NULL</code>.
     43  *    An Error will be returned if some required part of ICU data can not
     44  *    be loaded or initialized.
     45  *    The function returns immediately if the input error code indicates a
     46  *    failure, as usual.
     47  *
     48  * @stable ICU 2.6
     49  */
     50 U_STABLE void U_EXPORT2
     51 u_init(UErrorCode *status);
     52 
     53 #ifndef U_HIDE_SYSTEM_API
     54 /**
     55  * Clean up the system resources, such as allocated memory or open files,
     56  * used in all ICU libraries. This will free/delete all memory owned by the
     57  * ICU libraries, and return them to their original load state. All open ICU
     58  * items (collators, resource bundles, converters, etc.) must be closed before
     59  * calling this function, otherwise ICU may not free its allocated memory
     60  * (e.g. close your converters and resource bundles before calling this
     61  * function). Generally, this function should be called once just before
     62  * an application exits. For applications that dynamically load and unload
     63  * the ICU libraries (relatively uncommon), u_cleanup() should be called
     64  * just before the library unload.
     65  * <p>
     66  * u_cleanup() also clears any ICU heap functions, mutex functions or
     67  * trace functions that may have been set for the process.
     68  * This has the effect of restoring ICU to its initial condition, before
     69  * any of these override functions were installed.  Refer to
     70  * u_setMemoryFunctions(), u_setMutexFunctions and
     71  * utrace_setFunctions().  If ICU is to be reinitialized after after
     72  * calling u_cleanup(), these runtime override functions will need to
     73  * be set up again if they are still required.
     74  * <p>
     75  * u_cleanup() is not thread safe.  All other threads should stop using ICU
     76  * before calling this function.
     77  * <p>
     78  * Any open ICU items will be left in an undefined state by u_cleanup(),
     79  * and any subsequent attempt to use such an item will give unpredictable
     80  * results.
     81  * <p>
     82  * After calling u_cleanup(), an application may continue to use ICU by
     83  * calling u_init().  An application must invoke u_init() first from one single
     84  * thread before allowing other threads call u_init().  All threads existing
     85  * at the time of the first thread's call to u_init() must also call
     86  * u_init() themselves before continuing with other ICU operations.
     87  * <p>
     88  * The use of u_cleanup() just before an application terminates is optional,
     89  * but it should be called only once for performance reasons. The primary
     90  * benefit is to eliminate reports of memory or resource leaks originating
     91  * in ICU code from the results generated by heap analysis tools.
     92  * <p>
     93  * <strong>Use this function with great care!</strong>
     94  * </p>
     95  *
     96  * @stable ICU 2.0
     97  * @system
     98  */
     99 U_STABLE void U_EXPORT2
    100 u_cleanup(void);
    101 
    102 
    103 
    104 
    105 /**
    106   * An opaque pointer type that represents an ICU mutex.
    107   * For user-implemented mutexes, the value will typically point to a
    108   *  struct or object that implements the mutex.
    109   * @stable ICU 2.8
    110   * @system
    111   */
    112 typedef void *UMTX;
    113 
    114 /**
    115   *  Function Pointer type for a user supplied mutex initialization function.
    116   *  The user-supplied function will be called by ICU whenever ICU needs to create a
    117   *  new mutex.  The function implementation should create a mutex, and store a pointer
    118   *  to something that uniquely identifies the mutex into the UMTX that is supplied
    119   *  as a paramter.
    120   *  @param context user supplied value, obtained from from u_setMutexFunctions().
    121   *  @param mutex   Receives a pointer that identifies the new mutex.
    122   *                 The mutex init function must set the UMTX to a non-null value.
    123   *                 Subsequent calls by ICU to lock, unlock, or destroy a mutex will
    124   *                 identify the mutex by the UMTX value.
    125   *  @param status  Error status.  Report errors back to ICU by setting this variable
    126   *                 with an error code.
    127   *  @stable ICU 2.8
    128   *  @system
    129   */
    130 typedef void U_CALLCONV UMtxInitFn (const void *context, UMTX  *mutex, UErrorCode* status);
    131 
    132 
    133 /**
    134   *  Function Pointer type for a user supplied mutex functions.
    135   *  One of the  user-supplied functions with this signature will be called by ICU
    136   *  whenever ICU needs to lock, unlock, or destroy a mutex.
    137   *  @param context user supplied value, obtained from from u_setMutexFunctions().
    138   *  @param mutex   specify the mutex on which to operate.
    139   *  @stable ICU 2.8
    140   *  @system
    141   */
    142 typedef void U_CALLCONV UMtxFn   (const void *context, UMTX  *mutex);
    143 
    144 
    145 /**
    146   *  Set the functions that ICU will use for mutex operations
    147   *  Use of this function is optional; by default (without this function), ICU will
    148   *  directly access system functions for mutex operations
    149   *  This function can only be used when ICU is in an initial, unused state, before
    150   *  u_init() has been called.
    151   *  @param context This pointer value will be saved, and then (later) passed as
    152   *                 a parameter to the user-supplied mutex functions each time they
    153   *                 are called.
    154   *  @param init    Pointer to a mutex initialization function.  Must be non-null.
    155   *  @param destroy Pointer to the mutex destroy function.  Must be non-null.
    156   *  @param lock    pointer to the mutex lock function.  Must be non-null.
    157   *  @param unlock  Pointer to the mutex unlock function.  Must be non-null.
    158   *  @param status  Receives error values.
    159   *  @stable ICU 2.8
    160   *  @system
    161   */
    162 U_STABLE void U_EXPORT2
    163 u_setMutexFunctions(const void *context, UMtxInitFn *init, UMtxFn *destroy, UMtxFn *lock, UMtxFn *unlock,
    164                     UErrorCode *status);
    165 
    166 
    167 /**
    168   *  Pointer type for a user supplied atomic increment or decrement function.
    169   *  @param context user supplied value, obtained from from u_setAtomicIncDecFunctions().
    170   *  @param p   Pointer to a 32 bit int to be incremented or decremented
    171   *  @return    The value of the variable after the inc or dec operation.
    172   *  @stable ICU 2.8
    173   *  @system
    174   */
    175 typedef int32_t U_CALLCONV UMtxAtomicFn(const void *context, int32_t *p);
    176 
    177 /**
    178  *  Set the functions that ICU will use for atomic increment and decrement of int32_t values.
    179  *  Use of this function is optional; by default (without this function), ICU will
    180  *  use its own internal implementation of atomic increment/decrement.
    181  *  This function can only be used when ICU is in an initial, unused state, before
    182  *  u_init() has been called.
    183  *  @param context This pointer value will be saved, and then (later) passed as
    184  *                 a parameter to the increment and decrement functions each time they
    185  *                 are called.  This function can only be called
    186  *  @param inc     Pointer to a function to do an atomic increment operation.  Must be non-null.
    187  *  @param dec     Pointer to a function to do an atomic decrement operation.  Must be non-null.
    188  *  @param status  Receives error values.
    189  *  @stable ICU 2.8
    190  *  @system
    191  */
    192 U_STABLE void U_EXPORT2
    193 u_setAtomicIncDecFunctions(const void *context, UMtxAtomicFn *inc, UMtxAtomicFn *dec,
    194                     UErrorCode *status);
    195 
    196 
    197 
    198 /**
    199   *  Pointer type for a user supplied memory allocation function.
    200   *  @param context user supplied value, obtained from from u_setMemoryFunctions().
    201   *  @param size    The number of bytes to be allocated
    202   *  @return        Pointer to the newly allocated memory, or NULL if the allocation failed.
    203   *  @stable ICU 2.8
    204   *  @system
    205   */
    206 typedef void *U_CALLCONV UMemAllocFn(const void *context, size_t size);
    207 /**
    208   *  Pointer type for a user supplied memory re-allocation function.
    209   *  @param context user supplied value, obtained from from u_setMemoryFunctions().
    210   *  @param size    The number of bytes to be allocated
    211   *  @return        Pointer to the newly allocated memory, or NULL if the allocation failed.
    212   *  @stable ICU 2.8
    213   *  @system
    214   */
    215 typedef void *U_CALLCONV UMemReallocFn(const void *context, void *mem, size_t size);
    216 /**
    217   *  Pointer type for a user supplied memory free  function.  Behavior should be
    218   *  similar the standard C library free().
    219   *  @param context user supplied value, obtained from from u_setMemoryFunctions().
    220   *  @param mem     Pointer to the memory block to be resized
    221   *  @param size    The new size for the block
    222   *  @return        Pointer to the resized memory block, or NULL if the resizing failed.
    223   *  @stable ICU 2.8
    224   *  @system
    225   */
    226 typedef void  U_CALLCONV UMemFreeFn (const void *context, void *mem);
    227 
    228 /**
    229  *  Set the functions that ICU will use for memory allocation.
    230  *  Use of this function is optional; by default (without this function), ICU will
    231  *  use the standard C library malloc() and free() functions.
    232  *  This function can only be used when ICU is in an initial, unused state, before
    233  *  u_init() has been called.
    234  *  @param context This pointer value will be saved, and then (later) passed as
    235  *                 a parameter to the memory functions each time they
    236  *                 are called.
    237  *  @param a       Pointer to a user-supplied malloc function.
    238  *  @param r       Pointer to a user-supplied realloc function.
    239  *  @param f       Pointer to a user-supplied free function.
    240  *  @param status  Receives error values.
    241  *  @stable ICU 2.8
    242  *  @system
    243  */
    244 U_STABLE void U_EXPORT2
    245 u_setMemoryFunctions(const void *context, UMemAllocFn *a, UMemReallocFn *r, UMemFreeFn *f,
    246                     UErrorCode *status);
    247 #endif  /* U_HIDE_SYSTEM_API */
    248 
    249 #endif
    250