Fix: errors on shutdown & reload

[yaauie]

When an open connection is closed, an exception is raised; depending on timing and internal details of Socket#each, this is one of two exceptions:

• IOError (closed stream): when Socket#each advances after emitting an event, it checks to see if the socket is already closed, and emits this exception with a message "closed stream" if so.
• Errno::EBADF (Bad File Descriptor) - after checking the status of the stream and the underlying socket's file descriptor is cleaned up, subsequent reads will emit this exception.

In either case, log that the connection has closed and squash the exception, allowing a graceful shutdown of the input.

Resolves: logstash-plugins/logstash-input-syslog#40

[jordansissel]

Tested manually w/ gem build. This works with central configuration. LGTM.

[colinsurprenant]

LGTMT

[elasticsearch-bot]

Ry Biesemeyer merged this into the following branches!

Branch	Commits
master	7ccfc6d17f42315dbd7778f94d1d90f2dd087bec, b75992e33a7bb053a967df2da48570e7f83bbe53, c2c971524024766f90b5a54a4121fa0e7471e107