Explicitly unblock signals when selfpiped without signalfd

 This is arguably a bugfix, since selfpipe without signalfd
relies on signals being actually delivered, and a process may
have inherited a nonempty sigprocmask.

 Also use SIG_BLOCK instead of SIG_SETMASK when using
selfpipe_trapset() with signalfd, because we shouldn't unblock
signals that may have previously been blocked. This is also
arguably a bugfix.

 This commit is essential for using the version of s6-linux-init
that blocks SIGINT before disablecad on kernels without signalfd.
Without it, SIGINT never gets unblocked, so it's never delivered
to s6-svscan.

0 files changed, 0 insertions, 0 deletions