1 /*
2 *******************************************************************************
3 *
4 *   Copyright (C) 2003-2013, International Business Machines
5 *   Corporation and others.  All Rights Reserved.
6 *
7 *******************************************************************************
8 *   file name:  uarrsort.h
9 *   encoding:   US-ASCII
10 *   tab size:   8 (not used)
11 *   indentation:4
12 *
13 *   created on: 2003aug04
14 *   created by: Markus W. Scherer
15 *
16 *   Internal function for sorting arrays.
17 */
18 
19 #ifndef __UARRSORT_H__
20 #define __UARRSORT_H__
21 
22 #include "unicode/utypes.h"
23 
24 U_CDECL_BEGIN
25 /**
26  * Function type for comparing two items as part of sorting an array or similar.
27  * Callback function for uprv_sortArray().
28  *
29  * @param context Application-specific pointer, passed through by uprv_sortArray().
30  * @param left    Pointer to the "left" item.
31  * @param right   Pointer to the "right" item.
32  * @return 32-bit signed integer comparison result:
33  *                <0 if left<right
34  *               ==0 if left==right
35  *                >0 if left>right
36  *
37  * @internal
38  */
39 typedef int32_t U_CALLCONV
40 UComparator(const void *context, const void *left, const void *right);
41 U_CDECL_END
42 
43 /**
44  * Array sorting function.
45  * Uses a UComparator for comparing array items to each other, and simple
46  * memory copying to move items.
47  *
48  * @param array      The array to be sorted.
49  * @param length     The number of items in the array.
50  * @param itemSize   The size in bytes of each array item.
51  * @param cmp        UComparator function used to compare two items each.
52  * @param context    Application-specific pointer, passed through to the UComparator.
53  * @param sortStable If true, a stable sorting algorithm must be used.
54  * @param pErrorCode ICU in/out UErrorCode parameter.
55  *
56  * @internal
57  */
58 U_CAPI void U_EXPORT2
59 uprv_sortArray(void *array, int32_t length, int32_t itemSize,
60                UComparator *cmp, const void *context,
61                UBool sortStable, UErrorCode *pErrorCode);
62 
63 /**
64  * Convenience UComparator implementation for uint16_t arrays.
65  * @internal
66  */
67 U_CAPI int32_t U_EXPORT2
68 uprv_uint16Comparator(const void *context, const void *left, const void *right);
69 
70 /**
71  * Convenience UComparator implementation for int32_t arrays.
72  * @internal
73  */
74 U_CAPI int32_t U_EXPORT2
75 uprv_int32Comparator(const void *context, const void *left, const void *right);
76 
77 /**
78  * Convenience UComparator implementation for uint32_t arrays.
79  * @internal
80  */
81 U_CAPI int32_t U_EXPORT2
82 uprv_uint32Comparator(const void *context, const void *left, const void *right);
83 
84 /**
85  * Much like Java Collections.binarySearch(list, key, comparator).
86  *
87  * Except: Java documents "If the list contains multiple elements equal to
88  * the specified object, there is no guarantee which one will be found."
89  *
90  * This version here will return the largest index of any equal item,
91  * for use in stable sorting.
92  *
93  * @return the index>=0 where the item was found:
94  *         the largest such index, if multiple, for stable sorting;
95  *         or the index<0 for inserting the item at ~index in sorted order
96  */
97 U_CAPI int32_t U_EXPORT2
98 uprv_stableBinarySearch(char *array, int32_t length, void *item, int32_t itemSize,
99                         UComparator *cmp, const void *context);
100 
101 #endif
102