libc/fuzzing/stdlib/heap_sort_fuzz.cpp

   1 //===-- heap_sort_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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 ///
   9 /// Fuzzing test for llvm-libc heap_sort implementation.
  10 ///
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "src/stdlib/qsort_util.h"
  14 #include <stdint.h>
  15
  16 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  17   const size_t array_size = size / sizeof(int);
  18   if (array_size == 0)
  19     return 0;
  20
  21   int *array = new int[array_size];
  22   const int *data_as_int = reinterpret_cast<const int *>(data);
  23   for (size_t i = 0; i < array_size; ++i)
  24     array[i] = data_as_int[i];
  25
  26   const auto is_less = [](const void *a_ptr,
  27                           const void *b_ptr) noexcept -> bool {
  28     const int &a = *static_cast<const int *>(a_ptr);
  29     const int &b = *static_cast<const int *>(b_ptr);
  30
  31     return a < b;
  32   };
  33
  34   constexpr bool USE_QUICKSORT = false;
  35   LIBC_NAMESPACE::internal::unstable_sort_impl<USE_QUICKSORT>(
  36       array, array_size, sizeof(int), is_less);
  37
  38   for (size_t i = 0; i < array_size - 1; ++i) {
  39     if (array[i] > array[i + 1])
  40       __builtin_trap();
  41   }
  42
  43   delete[] array;
  44   return 0;
  45 }