blocking functions do not raise Errno::EINTR

Blocking functions should not raise Errno::EINTR to match
existing semantics of Ruby IO methods (e.g. IO.select, IO#read,
IO#write).  This makes user code easier to read/write.

Like th Ruby methods we emulate, we only reacquire the GVL on
EINTR to fire signal handlers, but otherwise emulate SA_RESTART
semantics.

This is a backwards-incompatible API change (but unlikely
to break existing code).

1 files changed, 6 insertions, 4 deletions

diff --git a/test/test_posix_mq.rb b/test/test_posix_mq.rb
index 5b78c22..8d6b014 100644
--- a/test/test_posix_mq.rb
+++ b/test/test_posix_mq.rb
@@ -118,16 +118,18 @@ class Test_POSIX_MQ < Test::Unit::TestCase
     end
     alarm or return warn "alarm() not found in #{libcs.inspect}"
     alarms = 0
-    trap("ALRM") { alarms += 1 }
+    trap("ALRM") do
+      alarms += 1
+      Thread.new { @mq.send("HI") }
+    end
     interval = 1
     alarm.call interval
     @mq = POSIX_MQ.new(@path, :rw)
     assert ! @mq.nonblock?
     t0 = Time.now
-    a = nil
-    assert_raises(Errno::EINTR) { a = @mq.receive }
+    a = @mq.receive
     elapsed = Time.now - t0
-    assert_nil a
+    assert_equal(["HI", 0], a)
     assert elapsed >= interval, elapsed.inspect
     assert elapsed < 1.10, elapsed.inspect
     assert_equal 1, alarms