1 //===-- Implementation of strncmp -----------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "src/string/strncmp.h"
10 
11 #include "src/__support/common.h"
12 #include <stddef.h>
13 
14 namespace __llvm_libc {
15 
16 // TODO: Look at benefits for comparing words at a time.
17 LLVM_LIBC_FUNCTION(int, strncmp,
18                    (const char *left, const char *right, size_t n)) {
19 
20   if (n == 0)
21     return 0;
22 
23   for (; n > 1; --n, ++left, ++right) {
24     char lc = *left;
25     if (lc == '\0' || lc != *right)
26       break;
27   }
28   return *reinterpret_cast<const unsigned char *>(left) -
29          *reinterpret_cast<const unsigned char *>(right);
30 }
31 
32 } // namespace __llvm_libc
33