[apple/icu.git] / icuSources / common / unicode / uenum.h

/*
*******************************************************************************
*
*   Copyright (C) 2002-2012, International Business Machines
*   Corporation and others.  All Rights Reserved.
*
*******************************************************************************
*   file name:  uenum.h
*   encoding:   US-ASCII
*   tab size:   8 (not used)
*   indentation:2
*
*   created on: 2002jul08
*   created by: Vladimir Weinstein
*/

#ifndef __UENUM_H
#define __UENUM_H

#include "unicode/utypes.h"
#include "unicode/localpointer.h"

#if U_SHOW_CPLUSPLUS_API
#include "unicode/strenum.h"
#endif

/**
 * \file
 * \brief C API: String Enumeration 
 */
 
/**
 * An enumeration object.
 * For usage in C programs.
 * @stable ICU 2.2
 */
struct UEnumeration;
/** structure representing an enumeration object instance @stable ICU 2.2 */
typedef struct UEnumeration UEnumeration;

/**
 * Disposes of resources in use by the iterator.  If en is NULL,
 * does nothing.  After this call, any char* or UChar* pointer
 * returned by uenum_unext() or uenum_next() is invalid.
 * @param en UEnumeration structure pointer
 * @stable ICU 2.2
 */
U_STABLE void U_EXPORT2
uenum_close(UEnumeration* en);

#if U_SHOW_CPLUSPLUS_API

U_NAMESPACE_BEGIN

/**
 * \class LocalUEnumerationPointer
 * "Smart pointer" class, closes a UEnumeration via uenum_close().
 * For most methods see the LocalPointerBase base class.
 *
 * @see LocalPointerBase
 * @see LocalPointer
 * @stable ICU 4.4
 */
U_DEFINE_LOCAL_OPEN_POINTER(LocalUEnumerationPointer, UEnumeration, uenum_close);

U_NAMESPACE_END

#endif

/**
 * Returns the number of elements that the iterator traverses.  If
 * the iterator is out-of-sync with its service, status is set to
 * U_ENUM_OUT_OF_SYNC_ERROR.
 * This is a convenience function. It can end up being very
 * expensive as all the items might have to be pre-fetched (depending
 * on the type of data being traversed). Use with caution and only 
 * when necessary.
 * @param en UEnumeration structure pointer
 * @param status error code, can be U_ENUM_OUT_OF_SYNC_ERROR if the
 *               iterator is out of sync.
 * @return number of elements in the iterator
 * @stable ICU 2.2
 */
U_STABLE int32_t U_EXPORT2
uenum_count(UEnumeration* en, UErrorCode* status);

/**
 * Returns the next element in the iterator's list.  If there are
 * no more elements, returns NULL.  If the iterator is out-of-sync
 * with its service, status is set to U_ENUM_OUT_OF_SYNC_ERROR and
 * NULL is returned.  If the native service string is a char* string,
 * it is converted to UChar* with the invariant converter.
 * The result is terminated by (UChar)0.
 * @param en the iterator object
 * @param resultLength pointer to receive the length of the result
 *                     (not including the terminating \\0).
 *                     If the pointer is NULL it is ignored.
 * @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
 *               the iterator is out of sync with its service.
 * @return a pointer to the string.  The string will be
 *         zero-terminated.  The return pointer is owned by this iterator
 *         and must not be deleted by the caller.  The pointer is valid
 *         until the next call to any uenum_... method, including
 *         uenum_next() or uenum_unext().  When all strings have been
 *         traversed, returns NULL.
 * @stable ICU 2.2
 */
U_STABLE const UChar* U_EXPORT2
uenum_unext(UEnumeration* en,
            int32_t* resultLength,
            UErrorCode* status);

/**
 * Returns the next element in the iterator's list.  If there are
 * no more elements, returns NULL.  If the iterator is out-of-sync
 * with its service, status is set to U_ENUM_OUT_OF_SYNC_ERROR and
 * NULL is returned.  If the native service string is a UChar*
 * string, it is converted to char* with the invariant converter.
 * The result is terminated by (char)0.  If the conversion fails
 * (because a character cannot be converted) then status is set to
 * U_INVARIANT_CONVERSION_ERROR and the return value is undefined
 * (but non-NULL).
 * @param en the iterator object
 * @param resultLength pointer to receive the length of the result
 *                     (not including the terminating \\0).
 *                     If the pointer is NULL it is ignored.
 * @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
 *               the iterator is out of sync with its service.  Set to
 *               U_INVARIANT_CONVERSION_ERROR if the underlying native string is
 *               UChar* and conversion to char* with the invariant converter
 *               fails. This error pertains only to current string, so iteration
 *               might be able to continue successfully.
 * @return a pointer to the string.  The string will be
 *         zero-terminated.  The return pointer is owned by this iterator
 *         and must not be deleted by the caller.  The pointer is valid
 *         until the next call to any uenum_... method, including
 *         uenum_next() or uenum_unext().  When all strings have been
 *         traversed, returns NULL.
 * @stable ICU 2.2
 */
U_STABLE const char* U_EXPORT2
uenum_next(UEnumeration* en,
           int32_t* resultLength,
           UErrorCode* status);

/**
 * Resets the iterator to the current list of service IDs.  This
 * re-establishes sync with the service and rewinds the iterator
 * to start at the first element.
 * @param en the iterator object
 * @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
 *               the iterator is out of sync with its service.  
 * @stable ICU 2.2
 */
U_STABLE void U_EXPORT2
uenum_reset(UEnumeration* en, UErrorCode* status);

#if U_SHOW_CPLUSPLUS_API

/**
 * Given a StringEnumeration, wrap it in a UEnumeration.  The
 * StringEnumeration is adopted; after this call, the caller must not
 * delete it (regardless of error status).
 * @param adopted the C++ StringEnumeration to be wrapped in a UEnumeration.
 * @param ec the error code.
 * @return a UEnumeration wrapping the adopted StringEnumeration.
 * @stable ICU 4.2
 */
U_CAPI UEnumeration* U_EXPORT2
uenum_openFromStringEnumeration(icu::StringEnumeration* adopted, UErrorCode* ec);

#endif

#endif
Commit	Line	Data
b75a7d8f A	1	/*
	2	*******************************************************************************
	3	*
4388f060	4	* Copyright (C) 2002-2012, International Business Machines
b75a7d8f A	5	* Corporation and others. All Rights Reserved.
	6	*
	7	*******************************************************************************
	8	* file name: uenum.h
	9	* encoding: US-ASCII
	10	* tab size: 8 (not used)
	11	* indentation:2
	12	*
	13	* created on: 2002jul08
	14	* created by: Vladimir Weinstein
	15	*/
	16
	17	#ifndef __UENUM_H
	18	#define __UENUM_H
	19
	20	#include "unicode/utypes.h"
729e4ab9 A	21	#include "unicode/localpointer.h"
	22
	23	#if U_SHOW_CPLUSPLUS_API
	24	#include "unicode/strenum.h"
	25	#endif
b75a7d8f	26
73c04bcf A	27	/**
	28	* \file
	29	* \brief C API: String Enumeration
	30	*/
	31
b75a7d8f A	32	/**
	33	* An enumeration object.
	34	* For usage in C programs.
374ca955	35	* @stable ICU 2.2
b75a7d8f A	36	*/
b75a7d8f A	37	struct UEnumeration;
374ca955	38	/** structure representing an enumeration object instance @stable ICU 2.2 */
b75a7d8f A	39	typedef struct UEnumeration UEnumeration;
	40
	41	/**
	42	* Disposes of resources in use by the iterator. If en is NULL,
	43	* does nothing. After this call, any char* or UChar* pointer
	44	* returned by uenum_unext() or uenum_next() is invalid.
	45	* @param en UEnumeration structure pointer
374ca955	46	* @stable ICU 2.2
b75a7d8f	47	*/
374ca955	48	U_STABLE void U_EXPORT2
b75a7d8f A	49	uenum_close(UEnumeration* en);
b75a7d8f A	50
729e4ab9 A	51	#if U_SHOW_CPLUSPLUS_API
	52
	53	U_NAMESPACE_BEGIN
	54
	55	/**
	56	* \class LocalUEnumerationPointer
	57	* "Smart pointer" class, closes a UEnumeration via uenum_close().
	58	* For most methods see the LocalPointerBase base class.
	59	*
	60	* @see LocalPointerBase
	61	* @see LocalPointer
	62	* @stable ICU 4.4
	63	*/
	64	U_DEFINE_LOCAL_OPEN_POINTER(LocalUEnumerationPointer, UEnumeration, uenum_close);
	65
	66	U_NAMESPACE_END
	67
	68	#endif
	69
b75a7d8f A	70	/**
	71	* Returns the number of elements that the iterator traverses. If
	72	* the iterator is out-of-sync with its service, status is set to
	73	* U_ENUM_OUT_OF_SYNC_ERROR.
	74	* This is a convenience function. It can end up being very
	75	* expensive as all the items might have to be pre-fetched (depending
	76	* on the type of data being traversed). Use with caution and only
	77	* when necessary.
	78	* @param en UEnumeration structure pointer
	79	* @param status error code, can be U_ENUM_OUT_OF_SYNC_ERROR if the
	80	* iterator is out of sync.
	81	* @return number of elements in the iterator
374ca955	82	* @stable ICU 2.2
b75a7d8f	83	*/
374ca955	84	U_STABLE int32_t U_EXPORT2
b75a7d8f A	85	uenum_count(UEnumeration* en, UErrorCode* status);
	86
	87	/**
	88	* Returns the next element in the iterator's list. If there are
	89	* no more elements, returns NULL. If the iterator is out-of-sync
	90	* with its service, status is set to U_ENUM_OUT_OF_SYNC_ERROR and
	91	* NULL is returned. If the native service string is a char* string,
	92	* it is converted to UChar* with the invariant converter.
	93	* The result is terminated by (UChar)0.
	94	* @param en the iterator object
	95	* @param resultLength pointer to receive the length of the result
374ca955	96	* (not including the terminating \\0).
b75a7d8f A	97	* If the pointer is NULL it is ignored.
	98	* @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
	99	* the iterator is out of sync with its service.
	100	* @return a pointer to the string. The string will be
	101	* zero-terminated. The return pointer is owned by this iterator
	102	* and must not be deleted by the caller. The pointer is valid
	103	* until the next call to any uenum_... method, including
	104	* uenum_next() or uenum_unext(). When all strings have been
	105	* traversed, returns NULL.
374ca955	106	* @stable ICU 2.2
b75a7d8f	107	*/
374ca955	108	U_STABLE const UChar* U_EXPORT2
b75a7d8f A	109	uenum_unext(UEnumeration* en,
	110	int32_t* resultLength,
	111	UErrorCode* status);
	112
	113	/**
	114	* Returns the next element in the iterator's list. If there are
	115	* no more elements, returns NULL. If the iterator is out-of-sync
	116	* with its service, status is set to U_ENUM_OUT_OF_SYNC_ERROR and
	117	* NULL is returned. If the native service string is a UChar*
	118	* string, it is converted to char* with the invariant converter.
	119	* The result is terminated by (char)0. If the conversion fails
	120	* (because a character cannot be converted) then status is set to
	121	* U_INVARIANT_CONVERSION_ERROR and the return value is undefined
	122	* (but non-NULL).
	123	* @param en the iterator object
	124	* @param resultLength pointer to receive the length of the result
374ca955	125	* (not including the terminating \\0).
b75a7d8f A	126	* If the pointer is NULL it is ignored.
	127	* @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
	128	* the iterator is out of sync with its service. Set to
	129	* U_INVARIANT_CONVERSION_ERROR if the underlying native string is
	130	* UChar* and conversion to char* with the invariant converter
	131	* fails. This error pertains only to current string, so iteration
	132	* might be able to continue successfully.
	133	* @return a pointer to the string. The string will be
	134	* zero-terminated. The return pointer is owned by this iterator
	135	* and must not be deleted by the caller. The pointer is valid
	136	* until the next call to any uenum_... method, including
	137	* uenum_next() or uenum_unext(). When all strings have been
	138	* traversed, returns NULL.
374ca955	139	* @stable ICU 2.2
b75a7d8f	140	*/
374ca955	141	U_STABLE const char* U_EXPORT2
b75a7d8f A	142	uenum_next(UEnumeration* en,
	143	int32_t* resultLength,
	144	UErrorCode* status);
	145
	146	/**
	147	* Resets the iterator to the current list of service IDs. This
	148	* re-establishes sync with the service and rewinds the iterator
	149	* to start at the first element.
	150	* @param en the iterator object
	151	* @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
	152	* the iterator is out of sync with its service.
374ca955	153	* @stable ICU 2.2
b75a7d8f	154	*/
374ca955	155	U_STABLE void U_EXPORT2
b75a7d8f A	156	uenum_reset(UEnumeration* en, UErrorCode* status);
b75a7d8f A	157
729e4ab9 A	158	#if U_SHOW_CPLUSPLUS_API
	159
	160	/**
	161	* Given a StringEnumeration, wrap it in a UEnumeration. The
	162	* StringEnumeration is adopted; after this call, the caller must not
	163	* delete it (regardless of error status).
	164	* @param adopted the C++ StringEnumeration to be wrapped in a UEnumeration.
	165	* @param ec the error code.
	166	* @return a UEnumeration wrapping the adopted StringEnumeration.
4388f060	167	* @stable ICU 4.2
729e4ab9 A	168	*/
729e4ab9 A	169	U_CAPI UEnumeration* U_EXPORT2
4388f060	170	uenum_openFromStringEnumeration(icu::StringEnumeration* adopted, UErrorCode* ec);
729e4ab9 A	171
	172	#endif
	173
b75a7d8f	174	#endif