contrib/fuzz/standalone_fuzz_target_runner.cc

remotefilelog-test: glob some flaky output line

This is similar to ee0959e7d435. The affected line is flaky underload, yet the
final result is correct.  The command involves background pre-check of output,
these are not stable probably because they run in parallel in multiple process.

If it become useful to start testing precise internal details of the, they will
have to be tested in a more appropriate framework than `.t` tests.

Differential Revision: https://phab.mercurial-scm.org/D8179

// Copyright 2017 Google Inc. All Rights Reserved.
// Licensed under the Apache License, Version 2.0 (the "License");

// Example of a standalone runner for "fuzz targets".
// It reads all files passed as parameters and feeds their contents
// one by one into the fuzz target (LLVMFuzzerTestOneInput).
// This runner does not do any fuzzing, but allows us to run the fuzz target
// on the test corpus (e.g. "do_stuff_test_data") or on a single file,
// e.g. the one that comes from a bug report.

#include <cassert>
#include <fstream>
#include <iostream>
#include <vector>

// Forward declare the "fuzz target" interface.
// We deliberately keep this inteface simple and header-free.
extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);

extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv);

int main(int argc, char **argv)
{
	LLVMFuzzerInitialize(&argc, &argv);

	for (int i = 1; i < argc; i++) {
		std::ifstream in(argv[i]);
		in.seekg(0, in.end);
		size_t length = in.tellg();
		in.seekg(0, in.beg);
		std::cout << "Reading " << length << " bytes from " << argv[i]
		          << std::endl;
		// Allocate exactly length bytes so that we reliably catch
		// buffer overflows.
		std::vector<char> bytes(length);
		in.read(bytes.data(), bytes.size());
		assert(in);
		LLVMFuzzerTestOneInput(
		    reinterpret_cast<const uint8_t *>(bytes.data()),
		    bytes.size());
		std::cout << "Execution successful" << std::endl;
	}
	return 0;
}
// no-check-code since this is from a third party