def test(encoded, endian, realendian=None):
            encoded_charp = rffi.str2charp(encoded)
            strict_charp = rffi.str2charp("strict")
            if endian is not None:
                if endian < 0:
                    value = -1
                elif endian > 0:
                    value = 1
                else:
                    value = 0
                pendian = lltype.malloc(rffi.INTP.TO, 1, flavor='raw')
                pendian[0] = rffi.cast(rffi.INT, value)
            else:
                pendian = None

            w_ustr = api.PyUnicode_DecodeUTF16(encoded_charp, len(encoded), strict_charp, pendian)
            assert space.eq_w(space.call_method(w_ustr, 'encode', space.wrap('ascii')),
                              space.wrap("abcd"))

            rffi.free_charp(encoded_charp)
            rffi.free_charp(strict_charp)
            if pendian:
                if realendian is not None:
                    assert rffi.cast(rffi.INT, realendian) == pendian[0]
                lltype.free(pendian, flavor='raw')

    def test_file_getline(self, space, api):
        filename = rffi.str2charp(str(udir / "_test_file"))

        mode = rffi.str2charp("w")
        w_file = api.PyFile_FromString(filename, mode)
        space.call_method(w_file, "write",
                          space.wrap("line1\nline2\nline3\nline4"))
        space.call_method(w_file, "close")

        rffi.free_charp(mode)
        mode = rffi.str2charp("r")
        w_file = api.PyFile_FromString(filename, mode)
        rffi.free_charp(filename)
        rffi.free_charp(mode)

        w_line = api.PyFile_GetLine(w_file, 0)
        assert space.str_w(w_line) == "line1\n"

        w_line = api.PyFile_GetLine(w_file, 4)
        assert space.str_w(w_line) == "line"

        w_line = api.PyFile_GetLine(w_file, 0)
        assert space.str_w(w_line) == "2\n"

        # XXX We ought to raise an EOFError here, but don't
        w_line = api.PyFile_GetLine(w_file, -1)
        # assert api.PyErr_Occurred() is space.w_EOFError
        assert space.str_w(w_line) == "line3\n"

        space.call_method(w_file, "close")

    def test_ascii_codec(self, space, api):
        s = 'abcdefg'
        data = rffi.str2charp(s)
        w_u = api.PyUnicode_DecodeASCII(data, len(s), lltype.nullptr(rffi.CCHARP.TO))
        assert space.eq_w(w_u, space.wrap(u"abcdefg"))
        rffi.free_charp(data)

        s = 'abcd\xFF'
        data = rffi.str2charp(s)
        self.raises(space, api, UnicodeDecodeError, api.PyUnicode_DecodeASCII,
                    data, len(s), lltype.nullptr(rffi.CCHARP.TO))
        rffi.free_charp(data)

        uni = u'abcdefg'
        data = rffi.unicode2wcharp(uni)
        w_s = api.PyUnicode_EncodeASCII(data, len(uni), lltype.nullptr(rffi.CCHARP.TO))
        assert space.eq_w(space.wrap("abcdefg"), w_s)
        rffi.free_wcharp(data)

        u = u'äbcdéfg'
        data = rffi.unicode2wcharp(u)
        w_s = api.PyUnicode_EncodeASCII(data, len(u), lltype.nullptr(rffi.CCHARP.TO))
        self.raises(space, api, UnicodeEncodeError, api.PyUnicode_EncodeASCII,
                    data, len(u), lltype.nullptr(rffi.CCHARP.TO))
        rffi.free_wcharp(data)

    def bindtextdomain(space, domain, w_dir):
        """bindtextdomain(domain, dir) -> string
        Bind the C library's domain to dir."""

        if space.is_w(w_dir, space.w_None):
            dir = None
            domain_c = rffi.str2charp(domain)
            try:
                dirname = _bindtextdomain(domain_c, dir)
            finally:
                rffi.free_charp(domain_c)
        else:
            dir = space.str_w(w_dir)
            domain_c = rffi.str2charp(domain)
            dir_c = rffi.str2charp(dir)
            try:
                dirname = _bindtextdomain(domain_c, dir_c)
            finally:
                rffi.free_charp(domain_c)
                rffi.free_charp(dir_c)

        if not dirname:
            errno = rposix.get_errno()
            raise OperationError(space.w_OSError, space.wrap(errno))
        return space.wrap(rffi.charp2str(dirname))

        def bind_textdomain_codeset(space, domain, w_codeset):
            """bind_textdomain_codeset(domain, codeset) -> string
            Bind the C library's domain to codeset."""

            if space.is_w(w_codeset, space.w_None):
                codeset = None
                domain_c = rffi.str2charp(domain)
                try:
                    result = _bind_textdomain_codeset(domain_c, codeset)
                finally:
                    rffi.free_charp(domain_c)
            else:
                codeset = space.str_w(w_codeset)
                domain_c = rffi.str2charp(domain)
                codeset_c = rffi.str2charp(codeset)
                try:
                    result = _bind_textdomain_codeset(domain_c, codeset_c)
                finally:
                    rffi.free_charp(domain_c)
                    rffi.free_charp(codeset_c)

            if not result:
                return space.w_None
            else:
                return space.wrap(rffi.charp2str(result))

    def dcgettext(space, w_domain, msg, category):
        """dcgettext(domain, msg, category) -> string
        Return translation of msg in domain and category."""

        if space.is_w(w_domain, space.w_None):
            domain = None
            msg_c = rffi.str2charp(msg)
            try:
                result = _dcgettext(domain, msg_c, rffi.cast(rffi.INT, category))
                # note that 'result' may be the same pointer as 'msg_c',
                # so it must be converted to an RPython string *before*
                # we free msg_c.
                result = rffi.charp2str(result)
            finally:
                rffi.free_charp(msg_c)
        else:
            domain = space.str_w(w_domain)
            domain_c = rffi.str2charp(domain)
            msg_c = rffi.str2charp(msg)
            try:
                result = _dcgettext(domain_c, msg_c,
                                    rffi.cast(rffi.INT, category))
                # note that 'result' may be the same pointer as 'msg_c',
                # so it must be converted to an RPython string *before*
                # we free msg_c.
                result = rffi.charp2str(result)
            finally:
                rffi.free_charp(domain_c)
                rffi.free_charp(msg_c)

        return space.wrap(result)

def strxfrm(space, s):
    "string -> string. Returns a string that behaves for cmp locale-aware."
    n1 = len(s) + 1

    buf = lltype.malloc(rffi.CCHARP.TO, n1, flavor="raw", zero=True)
    s_c = rffi.str2charp(s)
    try:
        n2 = _strxfrm(buf, s_c, n1) + 1
    finally:
        rffi.free_charp(s_c)
    if n2 > n1:
        # more space needed
        lltype.free(buf, flavor="raw")
        buf = lltype.malloc(rffi.CCHARP.TO, intmask(n2),
                            flavor="raw", zero=True)
        s_c = rffi.str2charp(s)
        try:
            _strxfrm(buf, s_c, n2)
        finally:
            rffi.free_charp(s_c)

    val = rffi.charp2str(buf)
    lltype.free(buf, flavor="raw")

    return space.wrap(val)

def strcoll(space, w_s1, w_s2):
    "string,string -> int. Compares two strings according to the locale."

    if space.is_true(space.isinstance(w_s1, space.w_str)) and \
       space.is_true(space.isinstance(w_s2, space.w_str)):

        s1, s2 = space.str_w(w_s1), space.str_w(w_s2)
        s1_c = rffi.str2charp(s1)
        s2_c = rffi.str2charp(s2)
        try:
            return space.wrap(_strcoll(s1_c, s2_c))
        finally:
            rffi.free_charp(s1_c)
            rffi.free_charp(s2_c)

    #if not space.is_true(space.isinstance(w_s1, space.w_unicode)) and \
    #   not space.is_true(space.isinstance(w_s2, space.w_unicode)):
    #    raise OperationError(space.w_ValueError,
    #                         space.wrap("strcoll arguments must be strings"))

    s1, s2 = space.unicode_w(w_s1), space.unicode_w(w_s2)

    s1_c = rffi.unicode2wcharp(s1)
    s2_c = rffi.unicode2wcharp(s2)
    try:
        result = _wcscoll(s1_c, s2_c)
    finally:
        rffi.free_wcharp(s1_c)
        rffi.free_wcharp(s2_c)

    return space.wrap(result)

    def test_AsEncodedObject(self, space, api):
        ptr = space.wrap('abc')

        errors = rffi.str2charp("strict")

        encoding = rffi.str2charp("hex")
        res = api.PyString_AsEncodedObject(
            ptr, encoding, errors)
        assert space.unwrap(res) == "616263"

        res = api.PyString_AsEncodedObject(
            ptr, encoding, lltype.nullptr(rffi.CCHARP.TO))
        assert space.unwrap(res) == "616263"
        rffi.free_charp(encoding)

        encoding = rffi.str2charp("unknown_encoding")
        self.raises(space, api, LookupError, api.PyString_AsEncodedObject,
                    ptr, encoding, errors)
        rffi.free_charp(encoding)

        rffi.free_charp(errors)

        res = api.PyString_AsEncodedObject(
            ptr, lltype.nullptr(rffi.CCHARP.TO), lltype.nullptr(rffi.CCHARP.TO))
        assert space.unwrap(res) == "abc"

        self.raises(space, api, TypeError, api.PyString_AsEncodedObject,
            space.wrap(2), lltype.nullptr(rffi.CCHARP.TO), lltype.nullptr(rffi.CCHARP.TO)
        )

 def test_dlopen(self):
     s = rffi.str2charp('xxxxxxxxxxxx')
     py.test.raises(DLOpenError, "dlopen(s)")
     rffi.free_charp(s)
     #
     s = rffi.str2charp(get_libc_name())
     assert dlopen(s)
     rffi.free_charp(s)

def test_strlen():
    strlen = rffi.llexternal('strlen', [rffi.CCHARP], lltype.Signed,
                             includes=['string.h'])
    s = rffi.str2charp("xxx")
    res = strlen(s)
    rffi.free_charp(s)
    assert res == 3
    s = rffi.str2charp("")
    res = strlen(s)
    rffi.free_charp(s)
    assert res == 0

 def test_strlen(self):
     eci = ExternalCompilationInfo(includes=['string.h'])
     strlen = rffi.llexternal('strlen', [rffi.CCHARP], rffi.SIZE_T,
                              compilation_info=eci)
     s = rffi.str2charp("xxx")
     res = strlen(s)
     rffi.free_charp(s)
     assert res == 3     # actually r_size_t(3)
     s = rffi.str2charp("")
     res = strlen(s)
     rffi.free_charp(s)
     assert res == 0     # actually r_size_t(0)
     assert not ALLOCATED     # detects memory leaks in the test

    def test_file_fromstring(self, space, api):
        filename = rffi.str2charp(str(udir / "_test_file"))
        mode = rffi.str2charp("wb")
        w_file = api.PyFile_FromString(filename, mode)
        rffi.free_charp(filename)
        rffi.free_charp(mode)

        assert api.PyFile_Check(w_file)
        assert api.PyFile_CheckExact(w_file)
        assert not api.PyFile_Check(space.wrap("text"))

        space.call_method(w_file, "write", space.wrap("text"))
        space.call_method(w_file, "close")
        assert (udir / "_test_file").read() == "text"

def get_new_method_def(space):
    state = space.fromcache(State)
    if state.new_method_def:
        return state.new_method_def
    from pypy.module.cpyext.modsupport import PyMethodDef
    ptr = lltype.malloc(PyMethodDef, flavor="raw", zero=True,
                        immortal=True)
    ptr.c_ml_name = rffi.str2charp("__new__")
    lltype.render_immortal(ptr.c_ml_name)
    rffi.setintfield(ptr, 'c_ml_flags', METH_VARARGS | METH_KEYWORDS)
    ptr.c_ml_doc = rffi.str2charp(
        "T.__new__(S, ...) -> a new object with type S, a subtype of T")
    lltype.render_immortal(ptr.c_ml_doc)
    state.new_method_def = ptr
    return ptr

def buffer_attach(space, py_obj, w_obj):
    """
    Fills a newly allocated PyBufferObject with the given (str) buffer object.
    """
    py_buf = rffi.cast(PyBufferObject, py_obj)
    py_buf.c_b_offset = 0
    rffi.setintfield(py_buf, 'c_b_readonly', 1)
    rffi.setintfield(py_buf, 'c_b_hash', -1)

    if isinstance(w_obj, SubBuffer):
        py_buf.c_b_offset = w_obj.offset
        w_obj = w_obj.buffer

    # If w_obj already allocated a fixed buffer, use it, and keep a
    # reference to w_obj.
    # Otherwise, b_base stays NULL, and we own the b_ptr.

    if isinstance(w_obj, StringBuffer):
        py_buf.c_b_base = lltype.nullptr(PyObject.TO)
        py_buf.c_b_ptr = rffi.cast(rffi.VOIDP, rffi.str2charp(w_obj.value))
        py_buf.c_b_size = w_obj.getlength()
    elif isinstance(w_obj, ArrayBuffer):
        w_base = w_obj.array
        py_buf.c_b_base = make_ref(space, w_base)
        py_buf.c_b_ptr = rffi.cast(rffi.VOIDP, w_obj.array._charbuf_start())
        py_buf.c_b_size = w_obj.getlength()
    else:
        raise OperationError(space.w_NotImplementedError, space.wrap(
            "buffer flavor not supported"))

 def test_setitemstring(self, space, api):
     w_d = space.newdict()
     key = rffi.str2charp("key")
     api.PyMapping_SetItemString(w_d, key, space.wrap(42))
     assert 42 == space.unwrap(
         api.PyMapping_GetItemString(w_d, key))
     rffi.free_charp(key)

def _make_mode(vm_path, path, bc, verbosity, mk_fresh):
    # Try to work out a plausible cached path name.
    dp = path.rfind(os.extsep)
    if dp >= 0 and os.sep not in path[dp:]:
        cp = path[:dp]
    else:
        cp = None
    
    if not cp or mk_fresh:
        return _do_make_mode(vm_path, path, None, verbosity, mk_fresh)
    else:
		# There is a cached path, so now we try and load it and see if it is upto date. If any part
		# of this fails, we simply go straight to full make mode.
        try:
            st = os.stat(cp)
        except OSError:
            return _do_make_mode(vm_path, path, cp, verbosity, mk_fresh)
        
        cbc, start = _read_bc(cp, "CONVEXEC")
        if start == -1:
            return _do_make_mode(vm_path, path, cp, verbosity, mk_fresh)
        
        assert start >= 0
        useful_bc = cbc[start:]
        if Bytecode.exec_upto_date(None, rffi.str2charp(useful_bc), st.st_mtime):
            return cbc, start, 0
        
        return _do_make_mode(vm_path, path, cp, verbosity, mk_fresh)

 def execv_lltypeimpl(path, args):
     l_path = rffi.str2charp(path)
     l_args = rffi.liststr2charpp(args)
     os_execv(l_path, l_args)
     rffi.free_charpp(l_args)
     rffi.free_charp(l_path)
     raise OSError(rffi.c_errno, "execv failed")

    def test_getattr(self, space, api):
        charp1 = rffi.str2charp("__len__")
        charp2 = rffi.str2charp("not_real")
        assert api.PyObject_GetAttrString(space.wrap(""), charp1)
        assert not api.PyObject_GetAttrString(space.wrap(""), charp2)
        assert api.PyErr_Occurred() is space.w_AttributeError
        api.PyErr_Clear()
        assert api.PyObject_DelAttrString(space.wrap(""), charp1) == -1
        assert api.PyErr_Occurred() is space.w_AttributeError
        api.PyErr_Clear()
        rffi.free_charp(charp1)
        rffi.free_charp(charp2)

        assert api.PyObject_GetAttr(space.wrap(""), space.wrap("__len__"))
        assert api.PyObject_DelAttr(space.wrap(""), space.wrap("__len__")) == -1
        api.PyErr_Clear()

def setlocale(space, category, w_locale=None):
    "(integer,string=None) -> string. Activates/queries locale processing."

    if cConfig.LC_MAX is not None:
        if not cConfig.LC_MIN <= category <= cConfig.LC_MAX:
            raise make_error(space, "invalid locale category")

    if space.is_w(w_locale, space.w_None) or w_locale is None:
        result = _setlocale(rffi.cast(rffi.INT, category), None)
        if not result:
            raise make_error(space, "locale query failed")
    else:
        locale = rffi.str2charp(space.str_w(w_locale))

        result = _setlocale(rffi.cast(rffi.INT, category), locale)
        if not result:
            raise make_error(space, "unsupported locale setting")

        # record changes to LC_CTYPE
        if category in (LC_CTYPE, LC_ALL):
            w_module = space.getbuiltinmodule('_locale')
            w_fun = space.getattr(w_module, space.wrap('_fixup_ulcase'))
            space.call_function(w_fun)

    return space.wrap(rffi.charp2str(result))