80164ef300
for_each_helper tries to calculate a one-past-the-end pointer for its wl_array input. This is fine when the array has one or more entries, but we initialize arrays by setting wl_array.data to NULL. Pointer arithmetic is only defined when both the pointer operand and the result point to the same allocation, or one-past-the-end of that allocation. As NULL points to no allocation, no pointer arithmetic can be performed on it, not even adding 0, even if the result is never dereferenced. This is caught by clang's ubsan from version 10. Many tests already hit this case, but I added an explicit test for iterating over an empty wl_map. Signed-off-by: Fergus Dall <sidereal@google.com> |
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.gitlab/issue_templates | ||
cursor | ||
doc | ||
egl | ||
protocol | ||
src | ||
tests | ||
.editorconfig | ||
.gitignore | ||
.gitlab-ci.yml | ||
CONTRIBUTING.md | ||
COPYING | ||
meson_options.txt | ||
meson.build | ||
publish-doc | ||
README | ||
releasing.txt | ||
wayland-scanner.m4 | ||
wayland-scanner.mk |
What is Wayland? Wayland is a project to define a protocol for a compositor to talk to its clients as well as a library implementation of the protocol. The compositor can be a standalone display server running on Linux kernel modesetting and evdev input devices, an X application, or a wayland client itself. The clients can be traditional applications, X servers (rootless or fullscreen) or other display servers. The wayland protocol is essentially only about input handling and buffer management. The compositor receives input events and forwards them to the relevant client. The clients creates buffers and renders into them and notifies the compositor when it needs to redraw. The protocol also handles drag and drop, selections, window management and other interactions that must go through the compositor. However, the protocol does not handle rendering, which is one of the features that makes wayland so simple. All clients are expected to handle rendering themselves, typically through cairo or OpenGL. The weston compositor is a reference implementation of a wayland compositor and the weston repository also includes a few example clients. Building the wayland libraries is fairly simple, aside from libffi, they don't have many dependencies: $ git clone https://gitlab.freedesktop.org/wayland/wayland $ cd wayland $ meson build/ --prefix=PREFIX $ ninja -C build/ install where PREFIX is where you want to install the libraries. See https://wayland.freedesktop.org for more complete build instructions for wayland, weston, xwayland and various toolkits.