Google
Edit File: uenum.h
// © 2016 and later: Unicode, Inc. and others. // License & terms of use: http://www.unicode.org/copyright.html /* ******************************************************************************* * * Copyright (C) 2002-2013, International Business Machines * Corporation and others. All Rights Reserved. * ******************************************************************************* * file name: uenum.h * encoding: UTF-8 * 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 U_NAMESPACE_BEGIN class StringEnumeration; U_NAMESPACE_END #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_STABLE UEnumeration* U_EXPORT2 uenum_openFromStringEnumeration(icu::StringEnumeration* adopted, UErrorCode* ec); #endif /** * Given an array of const UChar* strings, return a UEnumeration. String pointers from 0..count-1 must not be null. * Do not free or modify either the string array or the characters it points to until this object has been destroyed with uenum_close. * \snippet test/cintltst/uenumtst.c uenum_openUCharStringsEnumeration * @param strings array of const UChar* strings (each null terminated). All storage is owned by the caller. * @param count length of the array * @param ec error code * @return the new UEnumeration object. Caller is responsible for calling uenum_close to free memory. * @see uenum_close * @stable ICU 50 */ U_STABLE UEnumeration* U_EXPORT2 uenum_openUCharStringsEnumeration(const UChar* const strings[], int32_t count, UErrorCode* ec); /** * Given an array of const char* strings (invariant chars only), return a UEnumeration. String pointers from 0..count-1 must not be null. * Do not free or modify either the string array or the characters it points to until this object has been destroyed with uenum_close. * \snippet test/cintltst/uenumtst.c uenum_openCharStringsEnumeration * @param strings array of char* strings (each null terminated). All storage is owned by the caller. * @param count length of the array * @param ec error code * @return the new UEnumeration object. Caller is responsible for calling uenum_close to free memory * @see uenum_close * @stable ICU 50 */ U_STABLE UEnumeration* U_EXPORT2 uenum_openCharStringsEnumeration(const char* const strings[], int32_t count, UErrorCode* ec); #endif