There was a potential race where two handlers could be added at
the same time. Go Maps are not thread-safe, so that could do
unpleasant things. Add a mutex to keep things safe.
Also, swap the order or Register and Start for the handlers in
Libpod runtime created. As written, there was a small gap between
Start and Register where SIGTERM/SIGINT would be completely
ignored, instead of stopping Podman. Swapping the two closes this
gap.
Signed-off-by: Matthew Heon <mheon@redhat.com>
Installing a duplicate shutdown handler fails, but if a handler
with the same name is already present, we should be set to go.
There's no reason to print a user-facing error about it.
This comes up almost nowhere because Podman never makes more than
one Libpod runtime, but there is one exception (`system reset`)
and the error messages, while harmless, were making people very
confused (we got several bug reports that `system reset` was
nonfunctional).
Signed-off-by: Matthew Heon <mheon@redhat.com>
This allows us to run both the Libpod and Server handlers at the
same time without unregistering one.
Also, pass the signal that killed us into the handlers, in case
they want to use it to determine what to do (e.g. what exit code
to set).
Signed-off-by: Matthew Heon <mheon@redhat.com>
Expand the use of the Shutdown package such that we now use it
to handle signals any time we run Libpod. From there, add code to
container creation to use the Inhibit function to prevent a
shutdown from occuring during the critical parts of container
creation.
We also need to turn off signal handling when --sig-proxy is
invoked - we don't want to catch the signals ourselves then, but
instead to forward them into the container via the existing
sig-proxy handler.
Fixes#7941
Signed-off-by: Matthew Heon <mheon@redhat.com>
We need a unified package for handling signals that shut down
Libpod and Podman. We need to be able to do different things on
receiving such a signal (`system service` wants to shut down the
service gracefully, while most other commands just want to exit)
and we need to be able to inhibit this shutdown signal while we
are waiting for some critical operations (e.g. creating a
container) to finish. This takes the first step by defining the
package that will handle this.
Signed-off-by: Matthew Heon <mheon@redhat.com>
