Home | History | Annotate | Download | only in unicode
      1 //  2016 and later: Unicode, Inc. and others.
      2 // License & terms of use: http://www.unicode.org/copyright.html
      3 /*
      4 *******************************************************************************
      5 *
      6 *   Copyright (C) 2002-2013, International Business Machines
      7 *   Corporation and others.  All Rights Reserved.
      8 *
      9 *******************************************************************************
     10 *   file name:  uenum.h
     11 *   encoding:   UTF-8
     12 *   tab size:   8 (not used)
     13 *   indentation:2
     14 *
     15 *   created on: 2002jul08
     16 *   created by: Vladimir Weinstein
     17 */
     18 
     19 #ifndef __UENUM_H
     20 #define __UENUM_H
     21 
     22 #include "unicode/utypes.h"
     23 #include "unicode/localpointer.h"
     24 
     25 #if U_SHOW_CPLUSPLUS_API
     26 U_NAMESPACE_BEGIN
     27 class StringEnumeration;
     28 U_NAMESPACE_END
     29 #endif
     30 
     31 /**
     32  * \file
     33  * \brief C API: String Enumeration
     34  */
     35 
     36 /**
     37  * An enumeration object.
     38  * For usage in C programs.
     39  * @stable ICU 2.2
     40  */
     41 struct UEnumeration;
     42 /** structure representing an enumeration object instance @stable ICU 2.2 */
     43 typedef struct UEnumeration UEnumeration;
     44 
     45 /**
     46  * Disposes of resources in use by the iterator.  If en is NULL,
     47  * does nothing.  After this call, any char* or UChar* pointer
     48  * returned by uenum_unext() or uenum_next() is invalid.
     49  * @param en UEnumeration structure pointer
     50  * @stable ICU 2.2
     51  */
     52 U_STABLE void U_EXPORT2
     53 uenum_close(UEnumeration* en);
     54 
     55 #if U_SHOW_CPLUSPLUS_API
     56 
     57 U_NAMESPACE_BEGIN
     58 
     59 /**
     60  * \class LocalUEnumerationPointer
     61  * "Smart pointer" class, closes a UEnumeration via uenum_close().
     62  * For most methods see the LocalPointerBase base class.
     63  *
     64  * @see LocalPointerBase
     65  * @see LocalPointer
     66  * @stable ICU 4.4
     67  */
     68 U_DEFINE_LOCAL_OPEN_POINTER(LocalUEnumerationPointer, UEnumeration, uenum_close);
     69 
     70 U_NAMESPACE_END
     71 
     72 #endif
     73 
     74 /**
     75  * Returns the number of elements that the iterator traverses.  If
     76  * the iterator is out-of-sync with its service, status is set to
     77  * U_ENUM_OUT_OF_SYNC_ERROR.
     78  * This is a convenience function. It can end up being very
     79  * expensive as all the items might have to be pre-fetched (depending
     80  * on the type of data being traversed). Use with caution and only
     81  * when necessary.
     82  * @param en UEnumeration structure pointer
     83  * @param status error code, can be U_ENUM_OUT_OF_SYNC_ERROR if the
     84  *               iterator is out of sync.
     85  * @return number of elements in the iterator
     86  * @stable ICU 2.2
     87  */
     88 U_STABLE int32_t U_EXPORT2
     89 uenum_count(UEnumeration* en, UErrorCode* status);
     90 
     91 /**
     92  * Returns the next element in the iterator's list.  If there are
     93  * no more elements, returns NULL.  If the iterator is out-of-sync
     94  * with its service, status is set to U_ENUM_OUT_OF_SYNC_ERROR and
     95  * NULL is returned.  If the native service string is a char* string,
     96  * it is converted to UChar* with the invariant converter.
     97  * The result is terminated by (UChar)0.
     98  * @param en the iterator object
     99  * @param resultLength pointer to receive the length of the result
    100  *                     (not including the terminating \\0).
    101  *                     If the pointer is NULL it is ignored.
    102  * @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
    103  *               the iterator is out of sync with its service.
    104  * @return a pointer to the string.  The string will be
    105  *         zero-terminated.  The return pointer is owned by this iterator
    106  *         and must not be deleted by the caller.  The pointer is valid
    107  *         until the next call to any uenum_... method, including
    108  *         uenum_next() or uenum_unext().  When all strings have been
    109  *         traversed, returns NULL.
    110  * @stable ICU 2.2
    111  */
    112 U_STABLE const UChar* U_EXPORT2
    113 uenum_unext(UEnumeration* en,
    114             int32_t* resultLength,
    115             UErrorCode* status);
    116 
    117 /**
    118  * Returns the next element in the iterator's list.  If there are
    119  * no more elements, returns NULL.  If the iterator is out-of-sync
    120  * with its service, status is set to U_ENUM_OUT_OF_SYNC_ERROR and
    121  * NULL is returned.  If the native service string is a UChar*
    122  * string, it is converted to char* with the invariant converter.
    123  * The result is terminated by (char)0.  If the conversion fails
    124  * (because a character cannot be converted) then status is set to
    125  * U_INVARIANT_CONVERSION_ERROR and the return value is undefined
    126  * (but non-NULL).
    127  * @param en the iterator object
    128  * @param resultLength pointer to receive the length of the result
    129  *                     (not including the terminating \\0).
    130  *                     If the pointer is NULL it is ignored.
    131  * @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
    132  *               the iterator is out of sync with its service.  Set to
    133  *               U_INVARIANT_CONVERSION_ERROR if the underlying native string is
    134  *               UChar* and conversion to char* with the invariant converter
    135  *               fails. This error pertains only to current string, so iteration
    136  *               might be able to continue successfully.
    137  * @return a pointer to the string.  The string will be
    138  *         zero-terminated.  The return pointer is owned by this iterator
    139  *         and must not be deleted by the caller.  The pointer is valid
    140  *         until the next call to any uenum_... method, including
    141  *         uenum_next() or uenum_unext().  When all strings have been
    142  *         traversed, returns NULL.
    143  * @stable ICU 2.2
    144  */
    145 U_STABLE const char* U_EXPORT2
    146 uenum_next(UEnumeration* en,
    147            int32_t* resultLength,
    148            UErrorCode* status);
    149 
    150 /**
    151  * Resets the iterator to the current list of service IDs.  This
    152  * re-establishes sync with the service and rewinds the iterator
    153  * to start at the first element.
    154  * @param en the iterator object
    155  * @param status the error code, set to U_ENUM_OUT_OF_SYNC_ERROR if
    156  *               the iterator is out of sync with its service.
    157  * @stable ICU 2.2
    158  */
    159 U_STABLE void U_EXPORT2
    160 uenum_reset(UEnumeration* en, UErrorCode* status);
    161 
    162 #if U_SHOW_CPLUSPLUS_API
    163 
    164 /**
    165  * Given a StringEnumeration, wrap it in a UEnumeration.  The
    166  * StringEnumeration is adopted; after this call, the caller must not
    167  * delete it (regardless of error status).
    168  * @param adopted the C++ StringEnumeration to be wrapped in a UEnumeration.
    169  * @param ec the error code.
    170  * @return a UEnumeration wrapping the adopted StringEnumeration.
    171  * @stable ICU 4.2
    172  */
    173 U_STABLE UEnumeration* U_EXPORT2
    174 uenum_openFromStringEnumeration(icu::StringEnumeration* adopted, UErrorCode* ec);
    175 
    176 #endif
    177 
    178 /**
    179  * Given an array of const UChar* strings, return a UEnumeration.  String pointers from 0..count-1 must not be null.
    180  * Do not free or modify either the string array or the characters it points to until this object has been destroyed with uenum_close.
    181  * \snippet test/cintltst/uenumtst.c uenum_openUCharStringsEnumeration
    182  * @param strings array of const UChar* strings (each null terminated). All storage is owned by the caller.
    183  * @param count length of the array
    184  * @param ec error code
    185  * @return the new UEnumeration object. Caller is responsible for calling uenum_close to free memory.
    186  * @see uenum_close
    187  * @stable ICU 50
    188  */
    189 U_STABLE UEnumeration* U_EXPORT2
    190 uenum_openUCharStringsEnumeration(const UChar* const strings[], int32_t count,
    191                                  UErrorCode* ec);
    192 
    193 /**
    194  * Given an array of const char* strings (invariant chars only), return a UEnumeration.  String pointers from 0..count-1 must not be null.
    195  * Do not free or modify either the string array or the characters it points to until this object has been destroyed with uenum_close.
    196  * \snippet test/cintltst/uenumtst.c uenum_openCharStringsEnumeration
    197  * @param strings array of char* strings (each null terminated).  All storage is owned by the caller.
    198  * @param count length of the array
    199  * @param ec error code
    200  * @return the new UEnumeration object. Caller is responsible for calling uenum_close to free memory
    201  * @see uenum_close
    202  * @stable ICU 50
    203  */
    204 U_STABLE UEnumeration* U_EXPORT2
    205 uenum_openCharStringsEnumeration(const char* const strings[], int32_t count,
    206                                  UErrorCode* ec);
    207 
    208 #endif
    209