src/libcompiler_builtins/compiler-rt/test/fuzzer/RepeatedBytesTest.cpp

   1 // This file is distributed under the University of Illinois Open Source
   2 // License. See LICENSE.TXT for details.
   3
   4 // Simple test for a fuzzer. The fuzzer must find repeated bytes.
   5 #include <assert.h>
   6 #include <cstddef>
   7 #include <cstdint>
   8 #include <cstdlib>
   9 #include <iostream>
  10 #include <ostream>
  11
  12 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
  13   assert(Data);
  14   // Looking for AAAAAAAAAAAAAAAAAAAAAA or some such.
  15   size_t CurA = 0, MaxA = 0;
  16   for (size_t i = 0; i < Size; i++) {
  17     // Make sure there are no conditionals in the loop so that
  18     // coverage can't help the fuzzer.
  19     int EQ = Data[i] == 'A';
  20     CurA = EQ * (CurA + 1);
  21     int GT = CurA > MaxA;
  22     MaxA = GT * CurA + (!GT) * MaxA;
  23   }
  24   if (MaxA >= 20) {
  25     std::cout << "BINGO; Found the target (Max: " << MaxA << "), exiting\n"
  26               << std::flush;
  27     exit(0);
  28   }
  29   return 0;
  30 }
  31