1/*
2******************************************************************************
3*                                                                            *
4* Copyright (C) 2001-2009, International Business Machines                   *
5*                Corporation and others. All Rights Reserved.                *
6*                                                                            *
7******************************************************************************
8*   file name:  uclean.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 __UCLEAN_H__
18#define __UCLEAN_H__
19
20#include "unicode/utypes.h"
21/**
22 * \file
23 * \brief C API: Initialize and clean up ICU
24 */
25
26/**
27 *  Initialize ICU.
28 *
29 *  Use of this function is optional.  It is OK to simply use ICU
30 *  services and functions without first having initialized
31 *  ICU by calling u_init().
32 *
33 *  u_init() will attempt to load some part of ICU's data, and is
34 *  useful as a test for configuration or installation problems that
35 *  leave the ICU data inaccessible.  A successful invocation of u_init()
36 *  does not, however, guarantee that all ICU data is accessible.
37 *
38 *  Multiple calls to u_init() cause no harm, aside from the small amount
39 *  of time required.
40 *
41 *  In old versions of ICU, u_init() was required in multi-threaded applications
42 *  to ensure the thread safety of ICU.  u_init() is no longer needed for this purpose.
43 *
44 * @param status An ICU UErrorCode parameter. It must not be <code>NULL</code>.
45 *    An Error will be returned if some required part of ICU data can not
46 *    be loaded or initialized.
47 *    The function returns immediately if the input error code indicates a
48 *    failure, as usual.
49 *
50 * @stable ICU 2.6
51 */
52U_STABLE void U_EXPORT2
53u_init(UErrorCode *status);
54
55/**
56 * Clean up the system resources, such as allocated memory or open files,
57 * used in all ICU libraries. This will free/delete all memory owned by the
58 * ICU libraries, and return them to their original load state. All open ICU
59 * items (collators, resource bundles, converters, etc.) must be closed before
60 * calling this function, otherwise ICU may not free its allocated memory
61 * (e.g. close your converters and resource bundles before calling this
62 * function). Generally, this function should be called once just before
63 * an application exits. For applications that dynamically load and unload
64 * the ICU libraries (relatively uncommon), u_cleanup() should be called
65 * just before the library unload.
66 * <p>
67 * u_cleanup() also clears any ICU heap functions, mutex functions or
68 * trace functions that may have been set for the process.
69 * This has the effect of restoring ICU to its initial condition, before
70 * any of these override functions were installed.  Refer to
71 * u_setMemoryFunctions(), u_setMutexFunctions and
72 * utrace_setFunctions().  If ICU is to be reinitialized after after
73 * calling u_cleanup(), these runtime override functions will need to
74 * be set up again if they are still required.
75 * <p>
76 * u_cleanup() is not thread safe.  All other threads should stop using ICU
77 * before calling this function.
78 * <p>
79 * Any open ICU items will be left in an undefined state by u_cleanup(),
80 * and any subsequent attempt to use such an item will give unpredictable
81 * results.
82 * <p>
83 * After calling u_cleanup(), an application may continue to use ICU by
84 * calling u_init().  An application must invoke u_init() first from one single
85 * thread before allowing other threads call u_init().  All threads existing
86 * at the time of the first thread's call to u_init() must also call
87 * u_init() themselves before continuing with other ICU operations.
88 * <p>
89 * The use of u_cleanup() just before an application terminates is optional,
90 * but it should be called only once for performance reasons. The primary
91 * benefit is to eliminate reports of memory or resource leaks originating
92 * in ICU code from the results generated by heap analysis tools.
93 * <p>
94 * <strong>Use this function with great care!</strong>
95 * </p>
96 *
97 * @stable ICU 2.0
98 * @system
99 */
100U_STABLE void U_EXPORT2
101u_cleanup(void);
102
103
104
105
106/**
107  * An opaque pointer type that represents an ICU mutex.
108  * For user-implemented mutexes, the value will typically point to a
109  *  struct or object that implements the mutex.
110  * @stable ICU 2.8
111  * @system
112  */
113typedef void *UMTX;
114
115/**
116  *  Function Pointer type for a user supplied mutex initialization function.
117  *  The user-supplied function will be called by ICU whenever ICU needs to create a
118  *  new mutex.  The function implementation should create a mutex, and store a pointer
119  *  to something that uniquely identifies the mutex into the UMTX that is supplied
120  *  as a paramter.
121  *  @param context user supplied value, obtained from from u_setMutexFunctions().
122  *  @param mutex   Receives a pointer that identifies the new mutex.
123  *                 The mutex init function must set the UMTX to a non-null value.
124  *                 Subsequent calls by ICU to lock, unlock, or destroy a mutex will
125  *                 identify the mutex by the UMTX value.
126  *  @param status  Error status.  Report errors back to ICU by setting this variable
127  *                 with an error code.
128  *  @stable ICU 2.8
129  *  @system
130  */
131typedef void U_CALLCONV UMtxInitFn (const void *context, UMTX  *mutex, UErrorCode* status);
132
133
134/**
135  *  Function Pointer type for a user supplied mutex functions.
136  *  One of the  user-supplied functions with this signature will be called by ICU
137  *  whenever ICU needs to lock, unlock, or destroy a mutex.
138  *  @param context user supplied value, obtained from from u_setMutexFunctions().
139  *  @param mutex   specify the mutex on which to operate.
140  *  @stable ICU 2.8
141  *  @system
142  */
143typedef void U_CALLCONV UMtxFn   (const void *context, UMTX  *mutex);
144
145
146/**
147  *  Set the functions that ICU will use for mutex operations
148  *  Use of this function is optional; by default (without this function), ICU will
149  *  directly access system functions for mutex operations
150  *  This function can only be used when ICU is in an initial, unused state, before
151  *  u_init() has been called.
152  *  This function may be used even when ICU has been built without multi-threaded
153  *  support  (see ICU_USE_THREADS pre-processor variable, umutex.h)
154  *  @param context This pointer value will be saved, and then (later) passed as
155  *                 a parameter to the user-supplied mutex functions each time they
156  *                 are called.
157  *  @param init    Pointer to a mutex initialization function.  Must be non-null.
158  *  @param destroy Pointer to the mutex destroy function.  Must be non-null.
159  *  @param lock    pointer to the mutex lock function.  Must be non-null.
160  *  @param unlock  Pointer to the mutex unlock function.  Must be non-null.
161  *  @param status  Receives error values.
162  *  @stable ICU 2.8
163  *  @system
164  */
165U_STABLE void U_EXPORT2
166u_setMutexFunctions(const void *context, UMtxInitFn *init, UMtxFn *destroy, UMtxFn *lock, UMtxFn *unlock,
167                    UErrorCode *status);
168
169
170/**
171  *  Pointer type for a user supplied atomic increment or decrement function.
172  *  @param context user supplied value, obtained from from u_setAtomicIncDecFunctions().
173  *  @param p   Pointer to a 32 bit int to be incremented or decremented
174  *  @return    The value of the variable after the inc or dec operation.
175  *  @stable ICU 2.8
176  *  @system
177  */
178typedef int32_t U_CALLCONV UMtxAtomicFn(const void *context, int32_t *p);
179
180/**
181 *  Set the functions that ICU will use for atomic increment and decrement of int32_t values.
182 *  Use of this function is optional; by default (without this function), ICU will
183 *  use its own internal implementation of atomic increment/decrement.
184 *  This function can only be used when ICU is in an initial, unused state, before
185 *  u_init() has been called.
186 *  @param context This pointer value will be saved, and then (later) passed as
187 *                 a parameter to the increment and decrement functions each time they
188 *                 are called.  This function can only be called
189 *  @param inc     Pointer to a function to do an atomic increment operation.  Must be non-null.
190 *  @param dec     Pointer to a function to do an atomic decrement operation.  Must be non-null.
191 *  @param status  Receives error values.
192 *  @stable ICU 2.8
193 *  @system
194 */
195U_STABLE void U_EXPORT2
196u_setAtomicIncDecFunctions(const void *context, UMtxAtomicFn *inc, UMtxAtomicFn *dec,
197                    UErrorCode *status);
198
199
200
201/**
202  *  Pointer type for a user supplied memory allocation function.
203  *  @param context user supplied value, obtained from from u_setMemoryFunctions().
204  *  @param size    The number of bytes to be allocated
205  *  @return        Pointer to the newly allocated memory, or NULL if the allocation failed.
206  *  @stable ICU 2.8
207  *  @system
208  */
209typedef void *U_CALLCONV UMemAllocFn(const void *context, size_t size);
210/**
211  *  Pointer type for a user supplied memory re-allocation function.
212  *  @param context user supplied value, obtained from from u_setMemoryFunctions().
213  *  @param size    The number of bytes to be allocated
214  *  @return        Pointer to the newly allocated memory, or NULL if the allocation failed.
215  *  @stable ICU 2.8
216  *  @system
217  */
218typedef void *U_CALLCONV UMemReallocFn(const void *context, void *mem, size_t size);
219/**
220  *  Pointer type for a user supplied memory free  function.  Behavior should be
221  *  similar the standard C library free().
222  *  @param context user supplied value, obtained from from u_setMemoryFunctions().
223  *  @param mem     Pointer to the memory block to be resized
224  *  @param size    The new size for the block
225  *  @return        Pointer to the resized memory block, or NULL if the resizing failed.
226  *  @stable ICU 2.8
227  *  @system
228  */
229typedef void  U_CALLCONV UMemFreeFn (const void *context, void *mem);
230
231/**
232 *  Set the functions that ICU will use for memory allocation.
233 *  Use of this function is optional; by default (without this function), ICU will
234 *  use the standard C library malloc() and free() functions.
235 *  This function can only be used when ICU is in an initial, unused state, before
236 *  u_init() has been called.
237 *  @param context This pointer value will be saved, and then (later) passed as
238 *                 a parameter to the memory functions each time they
239 *                 are called.
240 *  @param a       Pointer to a user-supplied malloc function.
241 *  @param r       Pointer to a user-supplied realloc function.
242 *  @param f       Pointer to a user-supplied free function.
243 *  @param status  Receives error values.
244 *  @stable ICU 2.8
245 *  @system
246 */
247U_STABLE void U_EXPORT2
248u_setMemoryFunctions(const void *context, UMemAllocFn *a, UMemReallocFn *r, UMemFreeFn *f,
249                    UErrorCode *status);
250
251#endif
252