libc/src/string/strchr.cpp

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