After some investigation, it appears that SocketSet.Shutdown() and
SocketSet.Close() are not synchronous operations. The sendto system call
called in SocketSet.Shutdown() is not a blocking send. That means there
is a race in which SocketSet.Shutdown() sends a message to a file
descriptor to unblock select, while SocketSet.Close() will close the
file descriptor that the message is being sent to. If SocketSet.Close()
wins the race, select is listening on a dead file descriptor and will
hang indefinitely.
This is fixed in the current master by putting SocketSet.Close() inside
of the goroutine in which data from the socket is being received. It
relies on SocketSet.Shutdown() being called to terminate the goroutine.
While this works most of the time, there is a race here. All the
goroutines can also be terminated by a closeChan. If the goroutine
receives an event (thus unblocking select) and then closeChan is
triggered, both SocketSet.Shutdown() and SocketSet.Close() race, leading
to undefined behavior.
This patch ensures the ordering of the two function calls by pulling
them both out of the goroutine and separating them with a WaitGroup.
Co-authored-by: James Shubin <james@shubin.ca>
Add the ReceiveBytes, ReceiveNetlinkMessage, and ReceiveUEvent methods.
This is because not everything passed through a netlink socket cannot
reliably be parsed using the ParseNetLinkMessage function.
With the ReceiveUEvent method, we add support for "uevent" kernel
events, which updates us about the state of devices currently on the
system. To make using this method easier, we add a UEvent struct, that
has the action (what event), Devpath (where the device lives in /proc or
/sysfs), and Subsystem (what subsystem this event belows to).
This signals to an interested consumer that two or more compatible
resources can be merged safely. This is so that we can avoid the
"duplicate resource" design problem that puppet had.
To test this, you can run:
./mgmt run --tmp-prefix lang --lang 'pkg "cowsay" { state => "installed", } pkg "cowsay" { state => "newest", }'
which should work.
This is a subtle issue that was found that caused a panic. This should
solve things for now, but it would be wise to build embedded or
composite resources sparingly until we we're certain this would work the
way we wanted for all scenarios.
This improves some of the closing in the svc resource. This still needs
lots of improvements, and it's sort of terrible because it was some very
early code written.
This patch adds a util function, SessionBusUsable, that makes and returns
a new usable dbus session bus. If the svc bool session is true, the resource
will use a bus created with that function.
This adds the edgeable trait to the group resource and adds an
AutoEdges method which returns nil, nil. These changes are necessary
to allow UserRes to make autoedges to GroupRes.
This patch fixes a previously undiscovered bug which prevented
the use of the source field in the file resource. CheckApply was
returning early if obj.Content was nil. It is also necessary to
check that obj.Source is empty before returning, otherwise
syncCheckApply never runs.
In some scenarios it is desirable to set the addrs and gateway
independently, i.e. if a default gateway is already set on
the machine. This patch removes the requirement to set them
together.
This allows golang tests to be marked as root or !root using build tags.
The matching tests are then run as expected using our test runner.
This also disables test caching which is unfriendly to repeated test
running and is an absurd golang default to add.
Lastly this hooks up the testing verbose flag to tests that accept a
debug variable.
These tests aren't enabled on travis yet because of how it installs
golang.
This catches scenarios where we forgot to prefix the error with return.
One of our contributors occasionally made this typo, and since core go
vet didn't (surprisingly) catch it, we should add a test!
It also adds a simple check for import naming aliases. Expanding this
test to add other cases and check for differently named values might
make sense.
Arch Linux uses the mapping architecture name 'any'. This mapping was
missing from mgmt resulting in an error stating that arch 'any' did not
exist. Adding this mapping allows successful installation of packages
under Arch Linux.
This giant patch makes some much needed improvements to the code base.
* The engine has been rewritten and lives within engine/graph/
* All of the common interfaces and code now live in engine/
* All of the resources are in one package called engine/resources/
* The Res API can use different "traits" from engine/traits/
* The Res API has been simplified to hide many of the old internals
* The Watch & Process loops were previously inverted, but is now fixed
* The likelihood of package cycles has been reduced drastically
* And much, much more...
Unfortunately, some code had to be temporarily removed. The remote code
had to be taken out, as did the prometheus code. We hope to have these
back in new forms as soon as possible.
