1/*
2*******************************************************************************
3*   Copyright (C) 1997-2011, International Business Machines
4*   Corporation and others.  All Rights Reserved.
5*******************************************************************************
6*   file name:  uelement.h
7*   encoding:   US-ASCII
8*   tab size:   8 (not used)
9*   indentation:4
10*
11*   created on: 2011jul04
12*   created by: Markus W. Scherer
13*
14*   Common definitions for UHashTable and UVector.
15*   UHashTok moved here from uhash.h and renamed UElement.
16*   This allows users of UVector to avoid the confusing #include of uhash.h.
17*   uhash.h aliases UElement to UHashTok,
18*   so that we need not change all of its code and its users.
19*/
20
21#ifndef __UELEMENT_H__
22#define __UELEMENT_H__
23
24#include "unicode/utypes.h"
25
26U_CDECL_BEGIN
27
28/**
29 * A UVector element, or a key or value within a UHashtable.
30 * It may be either a 32-bit integral value or an opaque void* pointer.
31 * The void* pointer may be smaller than 32 bits (e.g. 24 bits)
32 * or may be larger (e.g. 64 bits).
33 *
34 * Because a UElement is the size of a native pointer or a 32-bit
35 * integer, we pass it around by value.
36 */
37union UElement {
38    void*   pointer;
39    int32_t integer;
40};
41typedef union UElement UElement;
42
43/**
44 * An element-equality (boolean) comparison function.
45 * @param e1 An element (object or integer)
46 * @param e2 An element (object or integer)
47 * @return TRUE if the two elements are equal.
48 */
49typedef UBool U_CALLCONV UElementsAreEqual(const UElement e1, const UElement e2);
50
51/**
52 * An element sorting (three-way) comparison function.
53 * @param e1 An element (object or integer)
54 * @param e2 An element (object or integer)
55 * @return 0 if the two elements are equal, -1 if e1 is < e2, or +1 if e1 is > e2.
56 */
57typedef int8_t U_CALLCONV UElementComparator(UElement e1, UElement e2);
58
59/**
60 * An element assignment function.  It may copy an integer, copy
61 * a pointer, or clone a pointer, as appropriate.
62 * @param dst The element to be assigned to
63 * @param src The element to assign from
64 */
65typedef void U_CALLCONV UElementAssigner(UElement *dst, UElement *src);
66
67U_CDECL_END
68
69/**
70 * Comparator function for UnicodeString* keys. Implements UElementsAreEqual.
71 * @param key1 The string for comparison
72 * @param key2 The string for comparison
73 * @return true if key1 and key2 are equal, return false otherwise.
74 */
75U_CAPI UBool U_EXPORT2
76uhash_compareUnicodeString(const UElement key1, const UElement key2);
77
78/**
79 * Comparator function for UnicodeString* keys (case insensitive).
80 * Make sure to use together with uhash_hashCaselessUnicodeString.
81 * Implements UElementsAreEqual.
82 * @param key1 The string for comparison
83 * @param key2 The string for comparison
84 * @return true if key1 and key2 are equal, return false otherwise.
85 */
86U_CAPI UBool U_EXPORT2
87uhash_compareCaselessUnicodeString(const UElement key1, const UElement key2);
88
89#endif  /* __UELEMENT_H__ */
90