// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// A simple unit-test style driver for libfuzzer tests.
// Usage: <fuzzer_test> <file>...

#include <stddef.h>
#include <stdint.h>

#include <fstream>
#include <iostream>
#include <iterator>
#include <vector>

// Libfuzzer API.
extern "C" {
  // User function.
  int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size);
  // Initialization function.
  __attribute__((weak)) int LLVMFuzzerInitialize(int *argc, char ***argv);
  // Mutation function provided by libFuzzer.
  size_t LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize);
}

std::vector<uint8_t> readFile(std::string path) {
  std::ifstream in(path);
  return std::vector<uint8_t>((std::istreambuf_iterator<char>(in)),
      std::istreambuf_iterator<char>());
}

size_t LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize) {
  return 0;
}

int main(int argc, char **argv) {
  if (argc == 1) {
    std::cerr
        << "Usage: " << argv[0]
        << " <file>...\n"
           "\n"
           "Alternatively, try building this target with "
           "use_libfuzzer=true for a better test driver. For details see:\n"
           "\n"
           "https://chromium.googlesource.com/chromium/src/+/main/"
           "testing/libfuzzer/getting_started.md"
        << std::endl;
    exit(1);
  }

  if (LLVMFuzzerInitialize)
    LLVMFuzzerInitialize(&argc, &argv);

  for (int i = 1; i < argc; ++i) {
    std::cout << argv[i] << std::endl;
    auto v = readFile(argv[i]);
    LLVMFuzzerTestOneInput(v.data(), v.size());
  }
}