summaryrefslogtreecommitdiff
path: root/deps/icu-small/source/common/unicode/uenum.h
blob: 56faae895279b6859324c89589357ddc90a6a037 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
// © 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);

/* Note:  next function is not hidden as draft, as it is used internally (it was formerly an internal function). */

/**
 * 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