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1//
2// wcscmp.cpp
3//
4// Copyright (c) Microsoft Corporation. All rights reserved.
5//
6// Defines wcscmp(), which compares two wide character strings, determining
7// their ordinal order.
8//
9// Note that the comparison is performed with unsigned elements (wchar_t is
10// unsigned in this implementation), so the null character (0) is less than
11// all other characters.
12//
13// Returns:
14// * -1 if a < b
15// * 0 if a == b
16// * 1 if a > b
17//
18#include <string.h>
19
20
21
22#if defined _M_X64 || defined _M_IX86 || defined _M_ARM || defined _M_ARM64
23 #pragma warning(disable: 4163)
24 #pragma function(wcscmp)
25#endif
26
27
28
29extern "C" int __cdecl wcscmp(wchar_t const* a, wchar_t const* b)
30{
31 int result = 0;
32#pragma warning(suppress:__WARNING_POTENTIAL_BUFFER_OVERFLOW_NULLTERMINATED) // 26018
33 while ((result = (int)(*a - *b)) == 0 && *b)
34 {
35 ++a;
36 ++b;
37 }
38
39 return ((-result) < 0) - (result < 0); // (if positive) - (if negative) generates branchless code
40}