| 1 | //===-- Implementation of wcsncmp -----------------------------------------===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | |
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| 9 | #include "src/wchar/wcsncmp.h" |
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| 10 | |
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| 11 | #include "hdr/types/size_t.h" |
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| 12 | #include "hdr/types/wchar_t.h" |
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| 13 | #include "src/__support/common.h" |
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| 14 | #include "src/__support/macros/null_check.h" |
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| 15 | |
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| 16 | namespace LIBC_NAMESPACE_DECL { |
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| 17 | |
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| 18 | LLVM_LIBC_FUNCTION(int, wcsncmp, |
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| 19 | (const wchar_t *left, const wchar_t *right, size_t n)) { |
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| 20 | LIBC_CRASH_ON_NULLPTR(left); |
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| 21 | LIBC_CRASH_ON_NULLPTR(right); |
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| 22 | |
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| 23 | if (n == 0) |
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| 24 | return 0; |
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| 25 | |
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| 26 | auto comp = [](wchar_t l, wchar_t r) -> int { return l - r; }; |
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| 27 | |
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| 28 | for (; n > 1; --n, ++left, ++right) { |
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| 29 | wchar_t lc = *left; |
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| 30 | if (!comp(lc, '\0') || comp(lc, *right)) |
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| 31 | break; |
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| 32 | } |
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| 33 | return comp(*reinterpret_cast<const wchar_t *>(left), |
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| 34 | *reinterpret_cast<const wchar_t *>(right)); |
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| 35 | } |
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| 36 | |
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| 37 | } // namespace LIBC_NAMESPACE_DECL |
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| 38 | |
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