view contrib/fuzz/xdiff.cc @ 49511:117dcc4a0e67

revset: handle wdir() in `sort(..., -topo)`

The last apparent usage of `repo.changelog.parentrevs` in revsets is in
`children()`, but since the sets being operated on never include wdir(), it's
never called with `wdirrev` and the wdir() arg on the command line is
effectively ignored instead of aborting there.  I'm not sure how to fix that.

Before (on a clone of hg):

    $ python3.8 hg perf::revset --config extensions.perf=contrib/perf.py 'sort(all(), -topo)'
    ! wall 0.123663 comb 0.130000 user 0.130000 sys 0.000000 (best of 76)

After:

    $ python3.8 hg perf::revset --config extensions.perf=contrib/perf.py 'sort(all(), -topo)'
    ! wall 0.123838 comb 0.130000 user 0.130000 sys 0.000000 (best of 75)

/*
 * 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>

#include "FuzzedDataProvider.h"

extern "C" {

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

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)
{
	// Don't allow fuzzer inputs larger than 100k, since we'll just bog
	// down and not accomplish much.
	if (Size > 100000) {
		return 0;
	}
	FuzzedDataProvider provider(Data, Size);
	std::string left = provider.ConsumeRandomLengthString(Size);
	std::string right = provider.ConsumeRemainingBytesAsString();
	mmfile_t a, b;

	a.ptr = (char *)left.c_str();
	a.size = left.size();
	b.ptr = (char *)right.c_str();
	b.size = right.size();
	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.
}

} // extern "C"