Wrapping ScreenRec's function pointers is problematic for many reasons,
so use the new window position notify hook instead.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Right now, extension specific actions on window positioning are implemented
by wrapping the ScreenRec's PositionWindow() proc pointer: the extensions are
storing the original pointer in their private data and putting in their own one.
On each call, their proc restores the original one, calls it, and switches back
again. When multiple extensions doing so, they're forming a kind of daisy chain.
(the same is done for lots of other procs)
While that approach is looking nice and elegant on the drawing board, it's
complicated, dangerous like a chainsaw and makes debugging hard, leading to
pretty blurred API borders.
This commit introduces a simple approach for letting extension hook into the
window positioning path safely, w/o having to care much about side effects
with the call chain. Extensions now can simply register their hook proc
(and an opaque pointer) and get called back - w/o ever having to mess with
the ScreenRec's internal structures. These hooks are called before the original
vector (usually handled by DDX/screen driver directly) is called.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Right now, extension specific window destruction procedures are implemented
by wrapping the ScreenRec's DestroyWindow() proc pointer: the extensions are
storing the original pointer in their private data and putting in their own one.
On each call, their proc restores the original one, calls it, and switches back
again. When multiple extensions doing so, they're forming a kind of daisy chain.
(the same is done for lots of other procs)
While that approach is looking nice and elegant on the drawing board, it's
complicated, dangerous like a chainsaw and makes debugging hard, leading to
pretty blurred API borders.
This commit introduces a simple approach for letting extension hook into the
window destruction safely, w/o having to care much about side effects with
the call chain. Extensions now can simply register their destructor proc
(and an opaque pointer) and get called back - w/o ever having to mess with
the ScreenRec's internal structures.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Allow using it by other places outside this file, so we can also support
callback lists in dynamically allocated structures:
Those cases need to explicitly call DeleteCallbackList() before free()ing
the structures - otherwise we're getting heap corruptions, because the
actual deletion can happen asynchronously.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Instead of retrieving the screen index from ScreenRec and passing this,
so the ScreenRec is looked up again, just pass in the ScreenPtr that
already have anyways.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Make it possible to call FreeGC() w/o prior NULL checks.
In case of NULL, BadMatch is returned.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Adding a little bit more logging to the startup process, eg. telling
when outputs or inputs have been initialized. Serving as a little aid for
debugging driver problems.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Even though it might never be actually hit, it's better to have an
(really cheap) extra check, just in case.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Even though it probably won't be hit ever, it's still better to be
really sure instead of some remote chance for hard segfault.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
As safety precaution, clear the pointers to extion records that just
have been free()ed.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The checking / branchin isn't entirely trivial to understand, and the
analyzer also gets confused. So rewrite it in an simpler way that's
easier to understand both the human reader as well as the analyzer.
(and so get rid of yet another false alarm)
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
For type-safety turn xfreeData() macro into an inline function.
Also adding some checks against accidentially free()'ing global data.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The analyzer giving a false alarm on potential NULL-pointer deref here.
Even though that case can't happen, it's also not immediately clear
to the human reader.
To make both the analyzer as well human reader happier, reformulating
this function to by using fast-return pattern.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The analyzer is wrong here, because the free'd closure pointer really points
to some calloc()'d chunk, instead of the PolyText()'s stack frame.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
It's safer not relying on all ScreenProc's actually filled.
../dix/events.c: In function ‘CheckPhysLimits’:
../dix/events.c:780:14: warning: dereference of NULL ‘pScreen’ [CWE-476] [-Wanalyzer-null-dereference]
780 | (*pScreen->SetCursorPosition)
| ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The pointer to the window properties is currently inside the WindowOptional
structure, which may or may not exist at any given time. Thus, before accessing
those fields, at least need to check whether it exists, potentially need to
create it first.
Since a pointer is small (in relation to WindowRec) and windows having properties
is a pretty common, we can make our life much simpler here by moving the pointer
directly into WindowRec, so we don't need extra WindowOptionalRec allocation.
This also fixes an analyzer warning on potential NULL dereference issue:
| ../dix/property.c: In function ‘dixChangeWindowProperty’:
|../dix/property.c:343:37: warning: dereference of NULL ‘*pWin.optional’ [CWE-476] [-Wanalyzer-null-dereference]
| 343 | pProp->next = pWin->optional->userProps;
| | ~~~~~~~~~~~~~~^~~~~~~~~~~
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
There's a (theoretical) chance that origGC might be NULL, so better
be cautious and check for this - doesn't cost us much, probably just
another JZ instruction.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Not used by any drivers, and subject to upcoming changes, so no need
to keep them exported.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
FOR_NSCREENS() is just alias for FOR_NSCREENS_BACKWARD(). In many cases
it really matters that we're going backwards and the last iteration visited
the screen #0, and that one is panoramix-wrapped.
Thus directly calling FOR_NSCREENS_BACKWARD() here and dropping the alias.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Not used by any exteral drivers (and really should not be used by them),
so can be replaced by more fitting error messages.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Not used by any drivers, so no need to keep it exported.
It's also so simple (and rarely called) that easily can be inlined.
Also unexport HWEventQueueType and HWEventQueuePtr, since they're
not used by any drivers.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Enrico Weigelt, metux IT consult