compiler-rt/test/fuzzer/BigFileCopy.cpp

   1 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   2 // See https://llvm.org/LICENSE.txt for license information.
   3 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   4
   5 #include <cstddef>
   6 #include <cstdint>
   7 #include <cstdio>
   8 #include <cstdlib>
   9 #include <cstring>
  10
  11 #include "FuzzerIO.h"
  12
  13 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
  14   const char *FileName = "big-file.txt";
  15   FILE *f = fopen(FileName, "w");
  16
  17   // This is the biggest file possible unless CopyFileToErr() uses Puts()
  18   fprintf(f, "%2147483646s", "2Gb-2");
  19
  20   // This makes the file too big if CopyFileToErr() uses fprintf("%s", <file>)
  21   fprintf(f, "THIS LINE RESPONSIBLE FOR EXCEEDING 2Gb FILE SIZE\n");
  22   fclose(f);
  23
  24   // Should now because CopyFileToErr() now uses Puts()
  25   fuzzer::CopyFileToErr(FileName);
  26
  27   // File is >2Gb so clean up
  28   remove(FileName);
  29
  30   return 0;
  31 }