def test_function_pointer(self):
ffi = FFI(backend=self.Backend())
def cb(charp):
assert repr(charp) == "<cdata 'char *'>"
return 42
fptr = ffi.callback("int(*)(const char *txt)", cb)
assert fptr != ffi.callback("int(*)(const char *)", cb)
assert repr(fptr) == "<cdata 'int(*)(char *)' calling %r>" % (cb, )
res = fptr("Hello")
assert res == 42
#
ffi.cdef("""
int puts(const char *);
int fflush(void *);
""")
fptr = ffi.cast("int(*)(const char *txt)", ffi.C.puts)
assert fptr == ffi.C.puts
assert repr(fptr) == "<cdata 'int(*)(char *)'>"
with FdWriteCapture() as fd:
fptr("world")
ffi.C.fflush(None)
res = fd.getvalue()
assert res == 'world\n'
def test_functionptr_simple(self):
ffi = FFI(backend=self.Backend())
py.test.raises(TypeError, ffi.callback, "int(*)(int)")
py.test.raises(TypeError, ffi.callback, "int(*)(int)", 0)
def cb(n):
return n + 1
p = ffi.callback("int(*)(int)", cb)
res = p(41) # calling an 'int(*)(int)', i.e. a function pointer
assert res == 42 and type(res) is int
res = p(ffi.cast("int", -41))
assert res == -40 and type(res) is int
assert repr(p).startswith(
"<cdata 'int(*)(int)' calling <function cb at 0x")
assert ffi.typeof(p) is ffi.typeof("int(*)(int)")
q = ffi.new("int(*)(int)", p)
assert repr(
q) == "<cdata 'int(* *)(int)' owning %d bytes>" % (SIZE_OF_PTR)
py.test.raises(TypeError, "q(43)")
res = q[0](43)
assert res == 44
q = ffi.cast("int(*)(int)", p)
assert repr(q) == "<cdata 'int(*)(int)'>"
res = q(45)
assert res == 46
def test_cast_functionptr_and_int(self):
ffi = FFI(backend=self.Backend())
def cb(n):
return n + 1
a = ffi.callback("int(*)(int)", cb)
p = ffi.cast("void *", a)
assert p
b = ffi.cast("int(*)(int)", p)
assert b(41) == 42
assert a == b
assert hash(a) == hash(b)
def test_cast_functionptr_and_int(self):
ffi = FFI(backend=self.Backend())
def cb(n):
return n + 1
a = ffi.callback("int(*)(int)", cb)
p = ffi.cast("void *", a)
assert p
b = ffi.cast("int(*)(int)", p)
assert b(41) == 42
assert a == b
assert hash(a) == hash(b)
def test_function_pointer(self):
ffi = FFI(backend=self.Backend())
def cb(charp):
assert repr(charp) == "<cdata 'char *'>"
return 42
fptr = ffi.callback("int(*)(const char *txt)", cb)
assert fptr != ffi.callback("int(*)(const char *)", cb)
assert repr(fptr) == "<cdata 'int(*)(char *)' calling %r>" % (cb,)
res = fptr("Hello")
assert res == 42
#
ffi.cdef("""
int puts(const char *);
int fflush(void *);
""")
fptr = ffi.cast("int(*)(const char *txt)", ffi.C.puts)
assert fptr == ffi.C.puts
assert repr(fptr) == "<cdata 'int(*)(char *)'>"
with FdWriteCapture() as fd:
fptr("world")
ffi.C.fflush(None)
res = fd.getvalue()
assert res == 'world\n'
def test_functionptr_simple(self):
ffi = FFI(backend=self.Backend())
py.test.raises(TypeError, ffi.callback, "int(*)(int)")
py.test.raises(TypeError, ffi.callback, "int(*)(int)", 0)
def cb(n):
return n + 1
p = ffi.callback("int(*)(int)", cb)
res = p(41) # calling an 'int(*)(int)', i.e. a function pointer
assert res == 42 and type(res) is int
res = p(ffi.cast("int", -41))
assert res == -40 and type(res) is int
assert repr(p).startswith(
"<cdata 'int(*)(int)' calling <function cb at 0x")
assert ffi.typeof(p) is ffi.typeof("int(*)(int)")
q = ffi.new("int(*)(int)", p)
assert repr(q) == "<cdata 'int(* *)(int)' owning %d bytes>" % (
SIZE_OF_PTR)
py.test.raises(TypeError, "q(43)")
res = q[0](43)
assert res == 44
q = ffi.cast("int(*)(int)", p)
assert repr(q) == "<cdata 'int(*)(int)'>"
res = q(45)
assert res == 46
