1// © 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3/*
4*******************************************************************************
5* Copyright (C) 1997-2011, International Business Machines
6* Corporation and others. All Rights Reserved.
7*******************************************************************************
8* file name: uelement.h
9* encoding: UTF-8
10* tab size: 8 (not used)
11* indentation:4
12*
13* created on: 2011jul04
14* created by: Markus W. Scherer
15*
16* Common definitions for UHashTable and UVector.
17* UHashTok moved here from uhash.h and renamed UElement.
18* This allows users of UVector to avoid the confusing #include of uhash.h.
19* uhash.h aliases UElement to UHashTok,
20* so that we need not change all of its code and its users.
21*/
22
23#ifndef __UELEMENT_H__
24#define __UELEMENT_H__
25
26#include "unicode/utypes.h"
27
28U_CDECL_BEGIN
29
30/**
31 * A UVector element, or a key or value within a UHashtable.
32 * It may be either a 32-bit integral value or an opaque void* pointer.
33 * The void* pointer may be smaller than 32 bits (e.g. 24 bits)
34 * or may be larger (e.g. 64 bits).
35 *
36 * Because a UElement is the size of a native pointer or a 32-bit
37 * integer, we pass it around by value.
38 */
39union UElement {
40 void* pointer;
41 int32_t integer;
42};
43typedef union UElement UElement;
44
45/**
46 * An element-equality (boolean) comparison function.
47 * @param e1 An element (object or integer)
48 * @param e2 An element (object or integer)
49 * @return true if the two elements are equal.
50 */
51typedef UBool U_CALLCONV UElementsAreEqual(const UElement e1, const UElement e2);
52
53/**
54 * An element sorting (three-way) comparison function.
55 * @param e1 An element (object or integer)
56 * @param e2 An element (object or integer)
57 * @return 32-bit signed integer comparison result:
58 * ==0 if the two elements are equal,
59 * <0 if e1 is < e2, or
60 * >0 if e1 is > e2.
61 */
62typedef int32_t U_CALLCONV UElementComparator(UElement e1, UElement e2);
63
64/**
65 * An element assignment function. It may copy an integer, copy
66 * a pointer, or clone a pointer, as appropriate.
67 * @param dst The element to be assigned to
68 * @param src The element to assign from
69 */
70typedef void U_CALLCONV UElementAssigner(UElement *dst, UElement *src);
71
72U_CDECL_END
73
74/**
75 * Comparator function for UnicodeString* keys. Implements UElementsAreEqual.
76 * @param key1 The string for comparison
77 * @param key2 The string for comparison
78 * @return true if key1 and key2 are equal, return false otherwise.
79 */
80U_CAPI UBool U_EXPORT2
81uhash_compareUnicodeString(const UElement key1, const UElement key2);
82
83/**
84 * Comparator function for UnicodeString* keys (case insensitive).
85 * Make sure to use together with uhash_hashCaselessUnicodeString.
86 * Implements UElementsAreEqual.
87 * @param key1 The string for comparison
88 * @param key2 The string for comparison
89 * @return true if key1 and key2 are equal, return false otherwise.
90 */
91U_CAPI UBool U_EXPORT2
92uhash_compareCaselessUnicodeString(const UElement key1, const UElement key2);
93
94#endif /* __UELEMENT_H__ */
95