Andrew Eikum wrote:
Nikolay Sivov wrote:
Andrew Eikum wrote:
dlls/gdiplus/gdiplus_private.h | 3 + dlls/gdiplus/graphics.c | 154 ++++++++++++++++++++++++++++++++++++++-- include/gdiplusflat.h | 1 + 3 files changed, 152 insertions(+), 6 deletions(-)
This looks wrong for me cause I don't think you could pass container id created with one Graphics to Graphics.EndContainer() of another. I've just checked it and it doesn't return any error code, but generated container ids aren't the same when you call BeginContainer() for e.g. two objects as sequent steps. It looks like on native these value are module unique, some kind of handle table needed. This kills the first problem I described - passing strange value to another Graphics.
Also note that Save()/Restore() functionality uses the same stack with container calls (at least msdn tells us that), for that Save/Restore we already have a test:
static void test_save_restore(void) .... /* The same state value should never be returned twice. */ todo_wine check_no_duplicates(state_log); ....
It clearly says that no duplicates allowed, even after multiple object deletion - it checks for values returned during the whole test.
I agree that the behavior of the container IDs doesn't match native. However, do we really care to duplicate that behavior? I can't see any documentation in MSDN that says container IDs must be unique across either graphics objects or within a single graphics object.
It doesn't matter is it explicitly documented or not. We should care only about how it really works.
I can't imagine any application depending on the uniqueness of container IDs; if they try to pass a container for graphics1 to graphics2, nothing happens, so there's no behavior to depend on.
If you create container c1 for graphics1 (0 numbered), then c2 for graphics2 (0 numbered too), then pop container for graphics2 with c1 value (c1 == c2) you implementation will successfully restore graphics2 to previous state. This doesn't happen on native - it will return Ok status, but status will be retained. This is a behavior we should depend on.
Ditto for invalid or already-used containers. The only scenario I can think of where the uniqueness of container IDs would be a dependency would be an application error calling EndContainer() with invalid values. I don't know if it's worth the effort of making a handle table and whatnot to work around an application glitch that might not even exist.
What you mean it might not? If somebody (e.g. me) will write a test for that will it exist then?
So, I would argue against the validity of the test you quote. Why should the same value not be returned twice?
Agreed, test isn't so obvious cause it shows that id value doesn't reoccur even after releasing containers. But test passes well on Windows, and only this matters here.
To simplify this we possibly could not to reproduce this exactly, but only guaranty ID uniqueness for currently valid Graphics objects in a process wide way.
After that we could consider making this test pass as a second step to get closer to native behavior.