michael@0: /*
michael@0: *******************************************************************************
michael@0: *   Copyright (C) 1997-2011, International Business Machines
michael@0: *   Corporation and others.  All Rights Reserved.
michael@0: *******************************************************************************
michael@0: *   file name:  uelement.h
michael@0: *   encoding:   US-ASCII
michael@0: *   tab size:   8 (not used)
michael@0: *   indentation:4
michael@0: *
michael@0: *   created on: 2011jul04
michael@0: *   created by: Markus W. Scherer
michael@0: *
michael@0: *   Common definitions for UHashTable and UVector.
michael@0: *   UHashTok moved here from uhash.h and renamed UElement.
michael@0: *   This allows users of UVector to avoid the confusing #include of uhash.h.
michael@0: *   uhash.h aliases UElement to UHashTok,
michael@0: *   so that we need not change all of its code and its users.
michael@0: */
michael@0: 
michael@0: #ifndef __UELEMENT_H__
michael@0: #define __UELEMENT_H__
michael@0: 
michael@0: #include "unicode/utypes.h"
michael@0: 
michael@0: U_CDECL_BEGIN
michael@0: 
michael@0: /**
michael@0:  * A UVector element, or a key or value within a UHashtable.
michael@0:  * It may be either a 32-bit integral value or an opaque void* pointer.
michael@0:  * The void* pointer may be smaller than 32 bits (e.g. 24 bits)
michael@0:  * or may be larger (e.g. 64 bits).
michael@0:  *
michael@0:  * Because a UElement is the size of a native pointer or a 32-bit
michael@0:  * integer, we pass it around by value.
michael@0:  */
michael@0: union UElement {
michael@0:     void*   pointer;
michael@0:     int32_t integer;
michael@0: };
michael@0: typedef union UElement UElement;
michael@0: 
michael@0: /**
michael@0:  * An element-equality (boolean) comparison function.
michael@0:  * @param e1 An element (object or integer)
michael@0:  * @param e2 An element (object or integer)
michael@0:  * @return TRUE if the two elements are equal.
michael@0:  */
michael@0: typedef UBool U_CALLCONV UElementsAreEqual(const UElement e1, const UElement e2);
michael@0: 
michael@0: /**
michael@0:  * An element sorting (three-way) comparison function.
michael@0:  * @param e1 An element (object or integer)
michael@0:  * @param e2 An element (object or integer)
michael@0:  * @return 0 if the two elements are equal, -1 if e1 is < e2, or +1 if e1 is > e2.
michael@0:  */
michael@0: typedef int8_t U_CALLCONV UElementComparator(UElement e1, UElement e2);
michael@0: 
michael@0: /**
michael@0:  * An element assignment function.  It may copy an integer, copy
michael@0:  * a pointer, or clone a pointer, as appropriate.
michael@0:  * @param dst The element to be assigned to
michael@0:  * @param src The element to assign from
michael@0:  */
michael@0: typedef void U_CALLCONV UElementAssigner(UElement *dst, UElement *src);
michael@0: 
michael@0: U_CDECL_END
michael@0: 
michael@0: /**
michael@0:  * Comparator function for UnicodeString* keys. Implements UElementsAreEqual.
michael@0:  * @param key1 The string for comparison
michael@0:  * @param key2 The string for comparison
michael@0:  * @return true if key1 and key2 are equal, return false otherwise.
michael@0:  */
michael@0: U_CAPI UBool U_EXPORT2 
michael@0: uhash_compareUnicodeString(const UElement key1, const UElement key2);
michael@0: 
michael@0: /**
michael@0:  * Comparator function for UnicodeString* keys (case insensitive).
michael@0:  * Make sure to use together with uhash_hashCaselessUnicodeString.
michael@0:  * Implements UElementsAreEqual.
michael@0:  * @param key1 The string for comparison
michael@0:  * @param key2 The string for comparison
michael@0:  * @return true if key1 and key2 are equal, return false otherwise.
michael@0:  */
michael@0: U_CAPI UBool U_EXPORT2 
michael@0: uhash_compareCaselessUnicodeString(const UElement key1, const UElement key2);
michael@0: 
michael@0: #endif  /* __UELEMENT_H__ */