contrib/fuzz/fncache.cc

dirstate: introduce a symbolic constant for the NONNORMAL marker

This is going to be clearer and easier to track than -1. Ultimately I would
like to get ride of this special value everywhere but in the lower level,
however we need to clarify the API first. This changeset is part of such
clarification.

Differential Revision: https://phab.mercurial-scm.org/D10927

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

#include "pyutil.h"

#include <iostream>
#include <string>

extern "C" {

static PYCODETYPE *code;

extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv)
{
	contrib::initpy(*argv[0]);
	code = (PYCODETYPE *)Py_CompileString(R"py(
try:
    for fn in (
        parsers.isasciistr,
        parsers.asciilower,
        parsers.asciiupper,
        parsers.encodedir,
        parsers.pathencode,
        parsers.lowerencode,
    ):
        try:
            fn(data)
        except UnicodeDecodeError:
            pass  # some functions emit this exception
        except AttributeError:
            # pathencode needs hashlib, which fails to import because the time
            # module fails to import. We should try and fix that some day, but
            # for now we at least get coverage on non-hashencoded codepaths.
            if fn != pathencode:
                raise
        # uncomment this for debugging exceptions
        # except Exception as e:
        #     raise Exception('%r: %r' % (fn, e))
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);
	if (!code) {
		std::cerr << "failed to compile Python code!" << std::endl;
	}
	return 0;
}

int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
	PyObject *mtext =
	    PyBytes_FromStringAndSize((const char *)Data, (Py_ssize_t)Size);
	PyObject *locals = PyDict_New();
	PyDict_SetItemString(locals, "data", mtext);
	PyObject *res = PyEval_EvalCode(code, contrib::pyglobals(), locals);
	if (!res) {
		PyErr_Print();
	}
	Py_XDECREF(res);
	Py_DECREF(locals);
	Py_DECREF(mtext);
	return 0; // Non-zero return values are reserved for future use.
}
}