/*

 * xdiff.cc - fuzzer harness for thirdparty/xdiff

 *

 * 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 "thirdparty/xdiff/xdiff.h"

#include <inttypes.h>

#include <stdlib.h>

extern "C" {

int hunk_consumer(long a1, long a2, long b1, long b2, void *priv)

{

	// TODO: probably also test returning -1 from this when things break?

	return 0;

}

int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)

{

	if (!Size) {

		return 0;

	}

	// figure out a random point in [0, Size] to split our input.

	size_t split = Data[0] / 255.0 * Size;

	mmfile_t a, b;

	// `a` input to diff is data[1:split]

	a.ptr = (char *)Data + 1;

	// which has len split-1

	a.size = split - 1;

	// `b` starts at the next byte after `a` ends

	b.ptr = a.ptr + a.size;

	b.size = Size - split;

	xpparam_t xpp = {

	    XDF_INDENT_HEURISTIC, /* flags */

	};

	xdemitconf_t xecfg = {

	    XDL_EMIT_BDIFFHUNK, /* flags */

	    hunk_consumer,      /* hunk_consume_func */

	};

	xdemitcb_t ecb = {

	    NULL, /* priv */

	};

	xdl_diff(&a, &b, &xpp, &xecfg, &ecb);

	return 0; // Non-zero return values are reserved for future use.

}

#ifdef HG_FUZZER_INCLUDE_MAIN

int main(int argc, char **argv)

{

	const char data[] = "asdf";

	return LLVMFuzzerTestOneInput((const uint8_t *)data, 4);

}

#endif

} // extern "C"