tree cca0434107def0bffdf3b997090603b0e2a72c92
parent ab16fcc8dbdff5779d09c306741a2e508fb9bd67
author Emmanuel Gil Peyrot <linkmauve@linkmauve.fr> 1538253332 +0200
committer linkmauve <linkmauve@linkmauve.fr> 1538392399 +0200

Wayland: Use memfd_create() and seals if available

This allows the compositor to avoid having to setup and teardown a
SIGBUS signal handler whenever it needs to read from this surface, as it
knows we won’t be able to shrink the file and so doesn’t have to protect
against that.

This codepath will only be used on Linux ≥ 3.17 with glibc ≥ 2.27, and
possibly other kernels and libc.  The former code will continue to be
used as a fallback, either if memfd_create() fails or if it isn’t
available.