revlog: implement changelogv2 packing and unpacking in C
This introduces a C implementation of changelogv2 records packing and unpacking
operations matching the pure Python counterpart, similarly to what we already
have for revlogv1 and revlogv2.
This is also necessary to access changelogv2 record fields from future Rust
code without going through the Python part, which would annihilate any
performance benefit.
Differential Revision: https://phab.mercurial-scm.org/D12178
/*
* 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"