All xserver sources need to include it at the very top anyways, so
no need to clutter public SDK headers with extra complexity.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
iterating over screen list via lambda-esque macros calls like this
DIX_FOR_EACH_SCREEN({
do_something
});
withing the body, the iterator variables `walkScreenIdx` and `walkScreen`
are defined and can be directly used (read-only). the code inside the body
is running in a separate scope.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Move functions/macros dealing with request parsing or reply assembly/write
out of the big dix_priv.h into their own headers. This new header will also
get more of those function/macros soon (yet still in the pipeline).
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
In Xinerama/Panoramix configuration there's one screen that's having special
meaning - it's used for simulating as the frontend for all client operations:
the clients (should) only talk to that screen, while panoramix subsystem is
proxying those operations to all the other screens (with certain changed
applied, eg. coordinate transformations).
Historically, this screen happens to be the first one in the system (some of
it's proc's are hooked up in order to achieve desired behaviour). That's why it
used to be accessed via screenInfo.screens[0] - that already had been encapsulated
into a tiny helper `dixGetFirstScreen()`.
a) the correct terminus technicus for a situation where one device (or SW entity)
entirely controlling others is a master-slave-relationship: the controlling
device/entity is `master`, the controlled ones are `slave` (to that specific
master).
b) the term "first screen" is inacurate and misleading here: what the caller's are
actually interest in isn't the first entry in the screen array, but the screen
that's controlling the others. With upcoming refactoring of the Xinerama/Panoramix
subsystem, this might well be a different array index than 0.
c) the term `default` also wouldn't match: `default` implies there's a real practical
choice, and such value applies when no explicit choice has been made. But in this
case, it practically doesn't make sense (except perhaps for debugging purpose)
for a client to use any different screen.
Therefore fixing the function name to the correct technical terminology.
(for sake of patch readability, renaming corresponding variables is left to
subsequent patches).
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Instead of everybody directly accessing the (internal) screenInfo struct,
let those consumers only interested in first screen use a little helper.
Also caching the value if it's needed several times.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Move the walking loops on Xinerama screens into lambda-esque macros:
the callers look quite like we've been using lambda functions and
closures, but actually are just fancy macro trickery.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
It's so trivial that those few lines can easily be inlined into
the actual request handler.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
When iterating screen lists, consistently use the same variable name
`walkScreenIdx` for holding current screen index everywhere.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The macro will automatically return BadAlloc if the buffer is broken,
otherwise Success. Thus, we don't need extra prior rpcbuf check.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Use x_rpcbuf_t for reply payload assembly, and X_SEND_REPLY_WITH_RPCBUF()
for sending out the whole reply.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Use x_rpcbuf_t for reply payload assembly, and X_SEND_REPLY_WITH_RPCBUF()
for sending out the whole replies.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
When iterating screen lists, consistently use the same variable name
`walkScreen` for holding current screen pointer everywhere.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
This reverts commit c32b5b4d5b.
The commit writes out of bounds with tchar[stuff->nbytes] write
since the string isn't null terminated.
This messed other data which makes requests fail and window managers/
desktop environments fail to start.
ProcXFixesSetCursorName also incorrectly uses dixGetAtomID
which doesn't create the atom if it doesn't exist, which it previously
did with MakeAtom(..., TRUE).
The new dixGet/AddAtom methods dont work without null-terminated strings
so the change has to be reverted instead.
Signed-off-by: dec05eba <dec05eba@protonmail.com>
Use the new shortcut helper for cases where we need to check
whether an atom exists and retrieve it's ID.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The handler of XFixesSetClientDisconnectMode does not check the client
request length.
A client could send a shorter request and read data from a former
request.
Fix the issue by checking the request size matches.
CVE-2025-49177
This issue was discovered by Nils Emmerich <nemmerich@ernw.de> and
reported by Julian Suleder via ERNW Vulnerability Disclosure.
Fixes: e167299f6 - xfixes: Add ClientDisconnectMode
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
Add hooks for filtering and fully rewrite rewrite selection requests
and events (what existing XACE hooks cannot do), e.g. for supporting
separate selection name spaces.
The hook can change individual fields in the parameter struct, so
operation continues with these changed values (eg. replace the original
selection name atom by a different one). It's also possible to stop
operations completely (with given result code) - in that case the
hook needs to take care of the remaining work to do (eg. sending events)
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
a) no need to checking for win->optional == NULL before calling
MakeWindowOptional(), because it checks itself
(except some cases where it's presence has it's own semantics,
or prevent unnecessary allocations)
b) lots of call sites didn't check for allocation failure.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Since most of the extension init logic (and on/off switches for them)
is driven from miext, this seems the appropriate place for the header.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
In general safer coding practise to always use calloc() instead of risking
forgetting to zero-out some fields.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Canonicalize all reply structs onto stack allocation and static
initialization, like already done in most other extension. So make
the code easier to understand and allow further simplifications by
subsequent commits (we can then use generic macros for doing the
actual sending, as well as byteorder swapping, size computation, etc),
Also gaining a little bit efficiency by skipping some heap allocations.
Dynamically sized payload buffers (where the upper bound isn't known),
are still allocated on heap.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The dispatcher functions are much more complex than they're usually are
(just switch/case statement). Bring them in line with the standard scheme
used in the Xserver, so further steps become easier.
It's also much cleaner to use the defines from proto headers instead of
raw numbers.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The current way of switching between Xinerama and single-screen handlers
is quite complicated and needs call vector tables that are changed on
the fly, which in turn makes dispatching more complicated.
Reworking this into a simple and straight code flow, where individual request
procs just look at a flag to decide whether to call the Xinerama or single
screen version.
This isn't just much easier to understand (and debug), but also removes the need
or the call vectors, thus allowing further simplification of the dispatcher.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Only key difference that calloc(), in contrast to rellocarray(),
is zero-initializing. The overhead is hard to measure on today's
machines, and it's safer programming practise to always allocate
zero-initialized, so one can't forget to do it explicitly.
Cocci rule:
@@
expression COUNT;
expression LEN;
@@
- xallocarray(COUNT,LEN)
+ calloc(COUNT,LEN)
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
* use their actual path instead of relying this to be in compiler's
include path list.
* no need to do it only conditionally, no #ifdef needed
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The request handler already does byte-swapping on its own, and
there's no extra reply-swap handler for it, so no need to call
into callbacks here.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
No need to have it ripped into two pieces, just making upcoming
changes more complicated.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Using calloc() instead of malloc() as preventive measure, so there
never can be any hidden bugs or leaks due uninitialized memory.
The extra cost of using this compiler intrinsic should be practically
impossible to measure - in many cases a good compiler can even deduce
if certain areas really don't need to be zero'd (because they're written
to right after allocation) and create more efficient machine code.
The code pathes in question are pretty cold anyways, so it's probably
not worth even thinking about potential extra runtime costs.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Wrapping ScreenRec's function pointers is problematic for many reasons,
so use the new screen close notify hook instead.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The private struct is pretty small and it needs to be allocated anyways,
so save an extra allocation by directly embedding it.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The include has become empty now. Not used by any external drivers,
so it can be dropped now.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
PANORAMIX was the original working title of the extension, before it became
official standard. Just nobody cared about fixing the symbols to the official
naming.
For backwards compatibility with drivers, the old PANORAMIX symbol will
still be set.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1258>
The symbol controls whether to include dix-config.h, and it's always set,
thus we don't need it (and dozens of ifdef's) anymore.
This commit only removes them from our own source files, where we can
guarantee that dix-config.h is present - leaving the (potentially exported)
headers untouched.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Clears -Wcalloc-transposed-args warnings from gcc 14.1, such as:
../dix/main.c:165:42: warning: ‘calloc’ sizes specified with ‘sizeof’ in the
earlier argument and not in the later argument [-Wcalloc-transposed-args]
165 | serverClient = calloc(sizeof(ClientRec), 1);
| ^~~~~~~~~
../dix/main.c:165:42: note: earlier argument should specify number of
elements, later size of each element
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1606>
