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 <cstdint>
7 #include <cstdlib>
8 #include <cstddef>
9 #include <iostream>
10 
LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)11 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
12   assert(Data);
13   // Looking for AAAAAAAAAAAAAAAAAAAAAA or some such.
14   size_t CurA = 0, MaxA = 0;
15   for (size_t i = 0; i < Size; i++) {
16     // Make sure there are no conditionals in the loop so that
17     // coverage can't help the fuzzer.
18     int EQ = Data[i] == 'A';
19     CurA = EQ * (CurA + 1);
20     int GT = CurA > MaxA;
21     MaxA = GT * CurA + (!GT) * MaxA;
22   }
23   if (MaxA >= 20) {
24     std::cout << "BINGO; Found the target (Max: " << MaxA << "), exiting\n";
25     exit(0);
26   }
27   return 0;
28 }
29 
30