linux/include/kunit
David Gow 56778b49c9 kunit: Add a macro to wrap a deferred action function
KUnit's deferred action API accepts a void(*)(void *) function pointer
which is called when the test is exited. However, we very frequently
want to use existing functions which accept a single pointer, but which
may not be of type void*. While this is probably dodgy enough to be on
the wrong side of the C standard, it's been often used for similar
callbacks, and gcc's -Wcast-function-type seems to ignore cases where
the only difference is the type of the argument, assuming it's
compatible (i.e., they're both pointers to data).

However, clang 16 has introduced -Wcast-function-type-strict, which no
longer permits any deviation in function pointer type. This seems to be
because it'd break CFI, which validates the type of function calls.

This rather ruins our attempts to cast functions to defer them, and
leaves us with a few options. The one we've chosen is to implement a
macro which will generate a wrapper function which accepts a void*, and
casts the argument to the appropriate type.

For example, if you were trying to wrap:
void foo_close(struct foo *handle);
you could use:
KUNIT_DEFINE_ACTION_WRAPPER(kunit_action_foo_close,
			    foo_close,
			    struct foo *);

This would create a new kunit_action_foo_close() function, of type
kunit_action_t, which could be passed into kunit_add_action() and
similar functions.

In addition to defining this macro, update KUnit and its tests to use
it.

Link: https://github.com/ClangBuiltLinux/linux/issues/1750
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-12-18 13:21:14 -07:00
..
assert.h kunit: remove KUNIT_INIT_MEM_ASSERTION macro 2022-12-12 14:13:47 -07:00
attributes.h kunit: Add ability to filter attributes 2023-07-26 13:29:15 -06:00
resource.h kunit: Add a macro to wrap a deferred action function 2023-12-18 13:21:14 -07:00
static_stub.h kunit: replace KUNIT_TRIGGER_STATIC_STUB maro with KUNIT_STATIC_STUB_REDIRECT 2023-08-13 13:23:56 -06:00
test-bug.h kunit: test-bug.h: include stddef.h for NULL 2023-07-18 15:38:13 -06:00
test.h kunit: Use string_stream for test log 2023-09-18 10:45:53 -06:00
try-catch.h kunit: hide unexported try-catch interface in try-catch-impl.h 2020-01-09 16:42:09 -07:00
visibility.h kunit: add macro to allow conditionally exposing static symbols to tests 2022-12-12 14:13:48 -07:00