contrib/fuzz/bdiff.cc

hghave: split apart testing for the curses module and `tic` executable

ef771d329961 skipped the check for the `tic` executable, because the curses
module alone on Windows is enough to pass the `test-*-curses.t` tests.  However,
`test-status-color.t` uses this same check and explicitly invoked the
executable, which fails on Windows.  From the cursory searching I did, curses on
unix requires `tic`, which I assume is why they were tied together in the first
place.  So this continues to require both to get past the curses guards on non
Windows platforms.

Differential Revision: https://phab.mercurial-scm.org/D9814

/*
 * bdiff.cc - fuzzer harness for bdiff.c
 *
 * Copyright 2018, Google Inc.
 *
 * This software may be used and distributed according to the terms of
 * the GNU General Public License, incorporated herein by reference.
 */
#include <memory>
#include <stdlib.h>

#include "FuzzedDataProvider.h"

extern "C" {
#include "bdiff.h"

extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv)
{
	return 0;
}

int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
	FuzzedDataProvider provider(Data, Size);
	std::string left = provider.ConsumeRandomLengthString(Size);
	std::string right = provider.ConsumeRemainingBytesAsString();

	struct bdiff_line *a, *b;
	int an = bdiff_splitlines(left.c_str(), left.size(), &a);
	int bn = bdiff_splitlines(right.c_str(), right.size(), &b);
	struct bdiff_hunk l;
	bdiff_diff(a, an, b, bn, &l);
	free(a);
	free(b);
	bdiff_freehunks(l.next);
	return 0; // Non-zero return values are reserved for future use.
}

} // extern "C"