d5cf2f5fc7
This provides an extended version of ‘create_pool’, called ‘create_pool2’, which allows the client to specify a 64-bit offset in the file to map at. As Wayland does not support 64-bit integers, the offset is passed as two 32-bit numbers. The intended use-case for this extension is when one needs to map a surface from a character special device, but it can also be used with regular files if one needs to map with a nonzero offset. Qubes OS needs the Wayland compositor to map the ‘/dev/xen/gntdev’ character device, which represents memory shared by a different Xen virtual machine. Currently, this can be accomplished by opening a separate instance of ‘/dev/xen/gntdev’ every time, but that is slightly wasteful. Until recently, it also on undocumented behavior in the kernel driver. This also requires libwayland-server to be built with 64-bit off_t, which should be supported on any reasonably modern system. A ‘_Static_assert’ will trip if off_t is not large enough. This also forbids resizing a pool of version 3 or later that is currently in use. On non-Linux systems, supporting pool resize requires holding the file descriptor open, which can lead to file descriptor exhaustion in the compositor. This change allows libwayland-server to close the file descriptor once the pool is first mapped. Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com> |
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| .editorconfig | ||
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| CONTRIBUTING.md | ||
| COPYING | ||
| meson.build | ||
| meson_options.txt | ||
| README.md | ||
| release.sh | ||
| releasing.txt | ||
| wayland-scanner.m4 | ||
| wayland-scanner.mk | ||
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.
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 documentation.