xref: /aosp_15_r20/external/llvm-libc/src/unistd/swab.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Implementation of swab --------------------------------------------===//
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/unistd/swab.h"
10 
11 #include "src/__support/common.h"
12 #include "src/__support/macros/config.h"
13 
14 namespace LIBC_NAMESPACE_DECL {
15 
16 LLVM_LIBC_FUNCTION(void, swab,
17                    (const void *__restrict from, void *__restrict to,
18                     ssize_t n)) {
19   const unsigned char *f = static_cast<const unsigned char *>(from);
20   unsigned char *t = static_cast<unsigned char *>(to);
21   for (ssize_t i = 1; i < n; i += 2) {
22     t[i - 1] = f[i];
23     t[i] = f[i - 1];
24   }
25 }
26 
27 } // namespace LIBC_NAMESPACE_DECL
28