/*
******************************************************************************
* *
* Copyright (C) 2001-2005, International Business Machines *
* Corporation and others. All Rights Reserved. *
* *
******************************************************************************
* file name: uclean.h
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* created on: 2001July05
* created by: George Rhoten
*/
#ifndef __UCLEAN_H__
#define __UCLEAN_H__
#include "unicode/utypes.h"
/**
* \file
* \brief C API: Initialize and clean up ICU
*/
/**
* Initialize ICU. The description further below applies to ICU 2.6 to ICU 3.4.
* Starting with ICU 3.4, u_init() needs not be called any more for
* ensuring thread safety, but it can give an indication for whether ICU
* can load its data. In ICU 3.4, it will try to load the converter alias table
* (cnvalias.icu) and give an error code if that fails.
* This may change in the future.
* <p>
* For ensuring the availability of necessary data, an application should
* open the service objects (converters, collators, etc.) that it will use
* and check for error codes there.
* <p>
* Documentation for ICU 2.6 to ICU 3.4:
* <p>
* This function loads and initializes data items
* that are required internally by various ICU functions. Use of this explicit
* initialization is required in multi-threaded applications; in
* single threaded apps, use is optional, but incurs little additional
* cost, and is thus recommended.
* <p>
* In multi-threaded applications, u_init() should be called in the
* main thread before starting additional threads, or, alternatively
* it can be called in each individual thread once, before other ICU
* functions are called in that thread. In this second scenario, the
* application must guarantee that the first call to u_init() happen
* without contention, in a single thread only.
* <p>
* If <code>u_setMemoryFunctions()</code> or
* <code>u_setMutexFunctions</code> are needed (uncommon), they must be
* called _before_ <code>u_init()</code>.
* <p>
* Extra, repeated, or otherwise unneeded calls to u_init() do no harm,
* other than taking a small amount of time.
*
* @param status An ICU UErrorCode parameter. It must not be <code>NULL</code>.
* An Error will be returned if some required part of ICU data can not
* be loaded or initialized.
* The function returns immediately if the input error code indicates a
* failure, as usual.
*
* @stable ICU 2.6
*/
U_STABLE void U_EXPORT2
u_init(UErrorCode *status);
/**
* Clean up the system resources, such as allocated memory or open files,
* used in all ICU libraries. This will free/delete all memory owned by the
* ICU libraries, and return them to their original load state. All open ICU
* items (collators, resource bundles, converters, etc.) must be closed before
* calling this function, otherwise ICU may not free its allocated memory
* (e.g. close your converters and resource bundles before calling this
* function). Generally, this function should be called once just before
* an application exits. For applications that dynamically load and unload
* the ICU libraries (relatively uncommon), u_cleanup() should be called
* just before the library unload.
* <p>
* u_cleanup() also clears any ICU heap functions, mutex functions or
* trace functions that may have been set for the process.
* This has the effect of restoring ICU to its initial condition, before
* any of these override functions were installed. Refer to
* u_setMemoryFunctions(), u_setMutexFunctions and
* utrace_setFunctions(). If ICU is to be reinitialized after after
* calling u_cleanup(), these runtime override functions will need to
* be set up again if they are still required.
* <p>
* u_cleanup() is not thread safe. All other threads should stop using ICU
* before calling this function.
* <p>
* Any open ICU items will be left in an undefined state by u_cleanup(),
* and any subsequent attempt to use such an item will give unpredictable
* results.
* <p>
* After calling u_cleanup(), an application may continue to use ICU by
* calling u_init(). An application must invoke u_init() first from one single
* thread before allowing other threads call u_init(). All threads existing
* at the time of the first thread's call to u_init() must also call
* u_init() themselves before continuing with other ICU operations.
* <p>
* The use of u_cleanup() just before an application terminates is optional,
* but it should be called only once for performance reasons. The primary
* benefit is to eliminate reports of memory or resource leaks originating
* in ICU code from the results generated by heap analysis tools.
* <p>
* <strong>Use this function with great care!</strong>
* </p>
*
* @stable ICU 2.0
* @system
*/
U_STABLE void U_EXPORT2
u_cleanup(void);
/**
* An opaque pointer type that represents an ICU mutex.
* For user-implemented mutexes, the value will typically point to a
* struct or object that implements the mutex.
* @stable ICU 2.8
* @system
*/
typedef void *UMTX;
/**
* Function Pointer type for a user supplied mutex initialization function.
* The user-supplied function will be called by ICU whenever ICU needs to create a
* new mutex. The function implementation should create a mutex, and store a pointer
* to something that uniquely identifies the mutex into the UMTX that is supplied
* as a paramter.
* @param context user supplied value, obtained from from u_setMutexFunctions().
* @param mutex Receives a pointer that identifies the new mutex.
* The mutex init function must set the UMTX to a non-null value.
* Subsequent calls by ICU to lock, unlock, or destroy a mutex will
* identify the mutex by the UMTX value.
* @param status Error status. Report errors back to ICU by setting this variable
* with an error code.
* @stable ICU 2.8
* @system
*/
typedef void U_CALLCONV UMtxInitFn (const void *context, UMTX *mutex, UErrorCode* status);
/**
* Function Pointer type for a user supplied mutex functions.
* One of the user-supplied functions with this signature will be called by ICU
* whenever ICU needs to lock, unlock, or destroy a mutex.
* @param context user supplied value, obtained from from u_setMutexFunctions().
* @param mutex specify the mutex on which to operate.
* @stable ICU 2.8
* @system
*/
typedef void U_CALLCONV UMtxFn (const void *context, UMTX *mutex);
/**
* Set the functions that ICU will use for mutex operations
* Use of this function is optional; by default (without this function), ICU will
* directly access system functions for mutex operations
* This function can only be used when ICU is in an initial, unused state, before
* u_init() has been called.
* This function may be used even when ICU has been built without multi-threaded
* support (see ICU_USE_THREADS pre-processor variable, umutex.h)
* @param context This pointer value will be saved, and then (later) passed as
* a parameter to the user-supplied mutex functions each time they
* are called.
* @param init Pointer to a mutex initialization function. Must be non-null.
* @param destroy Pointer to the mutex destroy function. Must be non-null.
* @param lock pointer to the mutex lock function. Must be non-null.
* @param unlock Pointer to the mutex unlock function. Must be non-null.
* @param status Receives error values.
* @stable ICU 2.8
* @system
*/
U_STABLE void U_EXPORT2
u_setMutexFunctions(const void *context, UMtxInitFn *init, UMtxFn *destroy, UMtxFn *lock, UMtxFn *unlock,
UErrorCode *status);
/**
* Pointer type for a user supplied atomic increment or decrement function.
* @param context user supplied value, obtained from from u_setAtomicIncDecFunctions().
* @param p Pointer to a 32 bit int to be incremented or decremented
* @return The value of the variable after the inc or dec operation.
* @stable ICU 2.8
* @system
*/
typedef int32_t U_CALLCONV UMtxAtomicFn(const void *context, int32_t *p);
/**
* Set the functions that ICU will use for atomic increment and decrement of int32_t values.
* Use of this function is optional; by default (without this function), ICU will
* use its own internal implementation of atomic increment/decrement.
* This function can only be used when ICU is in an initial, unused state, before
* u_init() has been called.
* @param context This pointer value will be saved, and then (later) passed as
* a parameter to the increment and decrement functions each time they
* are called. This function can only be called
* @param inc Pointer to a function to do an atomic increment operation. Must be non-null.
* @param dec Pointer to a function to do an atomic decrement operation. Must be non-null.
* @param status Receives error values.
* @stable ICU 2.8
* @system
*/
U_STABLE void U_EXPORT2
u_setAtomicIncDecFunctions(const void *context, UMtxAtomicFn *inc, UMtxAtomicFn *dec,
UErrorCode *status);
/**
* Pointer type for a user supplied memory allocation function.
* @param context user supplied value, obtained from from u_setMemoryFunctions().
* @param size The number of bytes to be allocated
* @return Pointer to the newly allocated memory, or NULL if the allocation failed.
* @stable ICU 2.8
* @system
*/
typedef void *U_CALLCONV UMemAllocFn(const void *context, size_t size);
/**
* Pointer type for a user supplied memory re-allocation function.
* @param context user supplied value, obtained from from u_setMemoryFunctions().
* @param size The number of bytes to be allocated
* @return Pointer to the newly allocated memory, or NULL if the allocation failed.
* @stable ICU 2.8
* @system
*/
typedef void *U_CALLCONV UMemReallocFn(const void *context, void *mem, size_t size);
/**
* Pointer type for a user supplied memory free function. Behavior should be
* similar the standard C library free().
* @param context user supplied value, obtained from from u_setMemoryFunctions().
* @param mem Pointer to the memory block to be resized
* @param size The new size for the block
* @return Pointer to the resized memory block, or NULL if the resizing failed.
* @stable ICU 2.8
* @system
*/
typedef void U_CALLCONV UMemFreeFn (const void *context, void *mem);
/**
* Set the functions that ICU will use for memory allocation.
* Use of this function is optional; by default (without this function), ICU will
* use the standard C library malloc() and free() functions.
* This function can only be used when ICU is in an initial, unused state, before
* u_init() has been called.
* @param context This pointer value will be saved, and then (later) passed as
* a parameter to the memory functions each time they
* are called.
* @param a Pointer to a user-supplied malloc function.
* @param r Pointer to a user-supplied realloc function.
* @param f Pointer to a user-supplied free function.
* @param status Receives error values.
* @stable ICU 2.8
* @system
*/
U_STABLE void U_EXPORT2
u_setMemoryFunctions(const void *context, UMemAllocFn *a, UMemReallocFn *r, UMemFreeFn *f,
UErrorCode *status);
#endif