1 //===-- Implementation of memchr ------------------------------------------===// 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/memchr.h" 10 #include "src/__support/common.h" 11 #include <stddef.h> 12 13 namespace __llvm_libc { 14 15 // TODO: Look at performance benefits of comparing words. 16 void *LLVM_LIBC_ENTRYPOINT(memchr)(const void *src, int c, size_t n) { 17 const unsigned char *str = reinterpret_cast<const unsigned char *>(src); 18 const unsigned char ch = c; 19 for (; n && *str != ch; --n, ++str) 20 ; 21 return n ? const_cast<unsigned char *>(str) : nullptr; 22 } 23 24 } // namespace __llvm_libc 25