annotate contrib/fuzz/manifest.cc @ 40084:2cf18f46a1ce

narrow: only walk files within narrowspec also for committed revisions

Narrow has been walking only paths matching the narrowspec when
walking the working copy. We have not done the same filtering when
walking committed revisions (e.g. "hg files -r "), which seems a
little odd. Let's make it consistent.

Differential Revision: https://phab.mercurial-scm.org/D4898

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

#include <string>

extern "C" {

/* TODO: use Python 3 for this fuzzing? */
PyMODINIT_FUNC initparsers(void);

static char cpypath[8192] = "\0";

extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv)
{
	const std::string subdir = "/sanpy/lib/python2.7";
	/* HACK ALERT: we need a full Python installation built without
	   pymalloc and with ASAN, so we dump one in
	   $OUT/sanpy/lib/python2.7. This helps us wire that up. */
	std::string selfpath(*argv[0]);
	std::string pypath;
	auto pos = selfpath.rfind("/");
	if (pos == std::string::npos) {
		char wd[8192];
		getcwd(wd, 8192);
		pypath = std::string(wd) + subdir;
	} else {
		pypath = selfpath.substr(0, pos) + subdir;
	}
	strncpy(cpypath, pypath.c_str(), pypath.size());
	setenv("PYTHONPATH", cpypath, 1);
	Py_SetPythonHome(cpypath);
	return 0;
}

int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
	Py_InitializeEx(0);
	initparsers();
	PyObject *mtext =
	    PyBytes_FromStringAndSize((const char *)Data, (Py_ssize_t)Size);
	PyObject *mainmod = PyImport_AddModule("__main__");
	PyObject *globals = PyModule_GetDict(mainmod);
	PyObject *locals = PyDict_New();
	PyDict_SetItemString(locals, "mdata", mtext);
	PyCodeObject *code =
	    (PyCodeObject *)Py_CompileString(R"py(
from parsers import lazymanifest
lm = lazymanifest(mdata)
try:
  # iterate the whole thing, which causes the code to fully parse
  # every line in the manifest
  list(lm.iterentries())
  lm[b'xyzzy'] = (b'\0' * 20, 'x')
  # do an insert, text should change
  assert lm.text() != mdata, "insert should change text and didn't: %r %r" % (lm.text(), mdata)
  del lm[b'xyzzy']
  # should be back to the same
  assert lm.text() == mdata, "delete should have restored text but didn't: %r %r" % (lm.text(), mdata)
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);
	PyEval_EvalCode(code, globals, locals);
	Py_DECREF(code);
	Py_DECREF(locals);
	Py_DECREF(mtext);
	Py_Finalize();
	return 0; // Non-zero return values are reserved for future use.
}
}