contrib/fuzz/revlog.cc

tests: perform a shallow copy instead of a deep copy

Python 3 can't perform a deep copy because it looks like symbols
in the locals() namespace are not deep-copyable. For the curious,
somehow the deepcopy() is attempting to copy objects attached to
the unittest.* functions for the running test!

We don't use deepcopy() anywhere in the code base and a shallow
object copy should be sufficient to test lock copying.

Actually, I'm not sure why we even test this, as I couldn't find
copy.copy() being used for lock copying either. Who knows.

Differential Revision: https://phab.mercurial-scm.org/D5770

#include <Python.h>
#include <assert.h>
#include <stdlib.h>
#include <unistd.h>

#include <string>

#include "pyutil.h"

extern "C" {

static PyCodeObject *code;

extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv)
{
	contrib::initpy(*argv[0]);
	code = (PyCodeObject *)Py_CompileString(R"py(
from parsers import parse_index2
for inline in (True, False):
    try:
        index, cache = parse_index2(data, inline)
        index.slicechunktodensity(list(range(len(index))), 0.5, 262144)
        for rev in range(len(index)):
            node = index[rev][7]
            partial = index.shortest(node)
            index.partialmatch(node[:partial])
    except Exception as e:
        pass
        # uncomment this print if you're editing this Python code
        # to debug failures.
        # print e
)py",
	                                        "fuzzer", Py_file_input);
	return 0;
}

int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
	// Don't allow fuzzer inputs larger than 60k, since we'll just bog
	// down and not accomplish much.
	if (Size > 60000) {
		return 0;
	}
	PyObject *text =
	    PyBytes_FromStringAndSize((const char *)Data, (Py_ssize_t)Size);
	PyObject *locals = PyDict_New();
	PyDict_SetItemString(locals, "data", text);
	PyObject *res = PyEval_EvalCode(code, contrib::pyglobals(), locals);
	if (!res) {
		PyErr_Print();
	}
	Py_XDECREF(res);
	Py_DECREF(locals);
	Py_DECREF(text);
	return 0; // Non-zero return values are reserved for future use.
}
}