55 lines · cpp
1//===-- bcmp_fuzz.cpp ---------------------------------------------------===//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-exception6//7//===----------------------------------------------------------------------===//8///9/// Fuzzing test for llvm-libc bcmp implementation.10///11//===----------------------------------------------------------------------===//12#include "src/strings/bcmp.h"13#include <stddef.h>14#include <stdint.h>15#include <stdio.h>16#include <string.h>17 18static int reference_bcmp(const void *pa, const void *pb, size_t count)19 __attribute__((no_builtin)) {20 const auto *a = reinterpret_cast<const unsigned char *>(pa);21 const auto *b = reinterpret_cast<const unsigned char *>(pb);22 for (size_t i = 0; i < count; ++i, ++a, ++b)23 if (*a != *b)24 return 1;25 return 0;26}27 28extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {29 const auto normalize = [](int value) -> int {30 if (value == 0)31 return 0;32 return 1;33 };34 // We ignore the last byte is size is odd.35 const auto count = size / 2;36 const char *a = reinterpret_cast<const char *>(data);37 const char *b = reinterpret_cast<const char *>(data) + count;38 const int actual = LIBC_NAMESPACE::bcmp(a, b, count);39 const int reference = reference_bcmp(a, b, count);40 if (normalize(actual) == normalize(reference))41 return 0;42 const auto print = [](const char *msg, const char *buffer, size_t size) {43 printf("%s\"", msg);44 for (size_t i = 0; i < size; ++i)45 printf("\\x%02x", (uint8_t)buffer[i]);46 printf("\"\n");47 };48 printf("count : %zu\n", count);49 print("a : ", a, count);50 print("b : ", b, count);51 printf("expected : %d\n", reference);52 printf("actual : %d\n", actual);53 __builtin_trap();54}55