| //===-- Implementation of strstr ------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "src/string/strstr.h" |
| |
| #include "src/__support/common.h" |
| #include <stddef.h> |
| |
| namespace __llvm_libc { |
| |
| // TODO: This is a simple brute force implementation. This can be |
| // improved upon using well known string matching algorithms. |
| LLVM_LIBC_FUNCTION(char *, strstr, (const char *haystack, const char *needle)) { |
| for (size_t i = 0; haystack[i]; ++i) { |
| size_t j; |
| for (j = 0; haystack[i + j] && haystack[i + j] == needle[j]; ++j) |
| ; |
| if (!needle[j]) |
| return const_cast<char *>(haystack + i); |
| } |
| return nullptr; |
| } |
| |
| } // namespace __llvm_libc |
