Use memfd_create() in Xwayland when available
This (so-far) Linux-only API lets users create file descriptors purely
in memory, without any backing file on the filesystem and the race
condition which could ensue when
It also allows seals to be placed on the file, ensuring to every other
process that we won’t be allowed to shrink the contents, potentially
SIGBUS when they try reading it.
This patch is best viewed with the
-w option of
git log -p.
This is a port of this commit from Weston: wayland/weston@deae98ef
I also included the unrelated removal of a duplicated
#include in the same file, I can put it in another MR if you prefer so.
Fixes #848 (closed).