BIND 10 #2398: msgq crash

[BIND 10 Development]

#2398: msgq crash
-------------------------------------+-------------------------------------
                   Reporter:  jreed  |                 Owner:  UnAssigned
                       Type:         |                Status:  reviewing
  defect                             |             Milestone:
                   Priority:         |  Sprint-20121204
  medium                             |            Resolution:
                  Component:  msgq   |             Sensitive:  0
                   Keywords:         |           Sub-Project:  Core
            Defect Severity:  High   |  Estimated Difficulty:  4
Feature Depending on Ticket:         |           Total Hours:  0
        Add Hours to Ticket:  0      |
                  Internal?:  0      |
-------------------------------------+-------------------------------------
Changes (by jelte):

 * owner:  jelte => UnAssigned
 * status:  assigned => reviewing


Comment:

 Ready for review.

 As far as msgq itself is concerned, I only addressed the SIGPIPE, which
 did not turn out to be much of a problem (there is already code to handle
 remote sockets that are suddenly closed, so it's really only a question of
 catching and handling the error).

 It does *not* handle and recover any other exceptions (except the socket
 errors that were already handled). I don't think we should catchall here,
 as depending on the exception we should handle it differently (and perhaps
 simply crash, if it is a syntax error for example). Also, I kept it to
 send() calls only. If we want we can do something similar for recv()
 (which should now be a lot easier, as I think the tests could be extended
 to test that too).

 As for the changes:

 Most of the diff is testing code. I took a look at the existing fork() and
 run() code, but it is a bit brittle imo, and chances are that it leaves
 processes hanging and it is difficult to communicate errors back to check
 for them.

 So I made a pretty simple and naive threading class that does nothing but
 call msgq.run() and store any exception it raises.

 Secondly, I added a BadSocket class which wraps an existing socket and
 optionally raises a given exception after a given number of bytes have
 been sent. I added tests for some existing handling (eagain and
 ewouldblock), and a few new ones.

-- 
Ticket URL: <http://bind10.isc.org/ticket/2398#comment:5>
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