Fix bugs in thread termination causing occasional pthread

assertion failures.

Before this, it was possible for J2KEncoder::terminate_threads()
to finish without terminating all threads if the thread _running_
terminate_threads() was itself interrupt()ed.

This is because the thread_group::join_all() in terminate_threads()
is an interruption point, so it was possible it not to complete
but instead to throw interrupted_exception.  Then the owning
J2KEncoder would be torn down but the threads would still be running,
causing use-after-frees.

This commit adds some boost::this_thread::disable_interruption
objects to ensure that the owning thread is not interrupted while
it is being destroyed.

Also tidy up code that does this stuff, assuming that it's safe
to not call thread::joinable but instead do

thread.interrupt();
try {
  thread.join();
} catch (...) {}

10 files changed, 44 insertions, 70 deletions

diff --git a/src/lib/butler.cc b/src/lib/butler.cc
index 595d98809..df2358086 100644
--- a/src/lib/butler.cc
+++ b/src/lib/butler.cc
@@ -101,6 +101,8 @@ Butler::Butler (
 
 Butler::~Butler ()
 {
+	boost::this_thread::disable_interruption dis;
+
 	{
 		boost::mutex::scoped_lock lm (_mutex);
 		_stop_thread = true;
@@ -113,9 +115,7 @@ Butler::~Butler ()
 	_thread.interrupt ();
 	try {
 		_thread.join ();
-	} catch (...) {
-
-	}
+	} catch (...) {}
 }
 
 /** Caller must hold a lock on _mutex */
diff --git a/src/lib/checker.cc b/src/lib/checker.cc
index c32462b42..b96b965aa 100644
--- a/src/lib/checker.cc
+++ b/src/lib/checker.cc
@@ -43,19 +43,17 @@ Checker::run ()
 
 Checker::~Checker ()
 {
+	boost::this_thread::disable_interruption dis;
+
 	{
 		boost::mutex::scoped_lock lm (_mutex);
 		_terminate = true;
 	}
 
-	if (_thread.joinable()) {
-		_thread.interrupt ();
-		try {
-			_thread.join ();
-		} catch (...) {
-
-		}
-	}
+	_thread.interrupt ();
+	try {
+		_thread.join ();
+	} catch (...) {}
 }
 
 void
diff --git a/src/lib/encode_server.cc b/src/lib/encode_server.cc
index c30fc8f30..f4224798b 100644
--- a/src/lib/encode_server.cc
+++ b/src/lib/encode_server.cc
@@ -83,6 +83,8 @@ EncodeServer::EncodeServer (bool verbose, int num_threads)
 
 EncodeServer::~EncodeServer ()
 {
+	boost::this_thread::disable_interruption dis;
+
 	{
 		boost::mutex::scoped_lock lm (_mutex);
 		_terminate = true;
@@ -104,13 +106,9 @@ EncodeServer::~EncodeServer ()
 	}
 
 	_broadcast.io_service.stop ();
-	if (_broadcast.thread.joinable()) {
-		try {
-			_broadcast.thread.join ();
-		} catch (...) {
-
-		}
-	}
+	try {
+		_broadcast.thread.join ();
+	} catch (...) {}
 }
 
 /** @param after_read Filled in with gettimeofday() after reading the input from the network.
diff --git a/src/lib/encode_server_finder.cc b/src/lib/encode_server_finder.cc
index 52c8c8949..7297734ec 100644
--- a/src/lib/encode_server_finder.cc
+++ b/src/lib/encode_server_finder.cc
@@ -70,25 +70,19 @@ EncodeServerFinder::~EncodeServerFinder ()
 void
 EncodeServerFinder::stop ()
 {
+	boost::this_thread::disable_interruption dis;
+
 	_stop = true;
 
 	_search_condition.notify_all ();
-	if (_search_thread.joinable()) {
-		try {
-			_search_thread.join();
-		} catch (...) {
-
-		}
-	}
+	try {
+		_search_thread.join();
+	} catch (...) {}
 
 	_listen_io_service.stop ();
-	if (_listen_thread.joinable()) {
-		try {
-			_listen_thread.join ();
-		} catch (...) {
-
-		}
-	}
+	try {
+		_listen_thread.join ();
+	} catch (...) {}
 
 	boost::mutex::scoped_lock lm (_servers_mutex);
 	_servers.clear ();
diff --git a/src/lib/hints.cc b/src/lib/hints.cc
index 9cc10d735..e936332a2 100644
--- a/src/lib/hints.cc
+++ b/src/lib/hints.cc
@@ -69,17 +69,13 @@ Hints::start ()
 
 Hints::~Hints ()
 {
-	if (!_thread.joinable()) {
-		return;
-	}
+	boost::this_thread::disable_interruption dis;
 
 	try {
 		_stop = true;
 		_thread.interrupt ();
 		_thread.join ();
-	} catch (...) {
-
-	}
+	} catch (...) {}
 }
 
 void
diff --git a/src/lib/j2k_encoder.cc b/src/lib/j2k_encoder.cc
index d8d8209c9..4e2a30ef7 100644
--- a/src/lib/j2k_encoder.cc
+++ b/src/lib/j2k_encoder.cc
@@ -64,14 +64,7 @@ J2KEncoder::J2KEncoder (shared_ptr<const Film> film, shared_ptr<Writer> writer)
 
 J2KEncoder::~J2KEncoder ()
 {
-	try {
-		terminate_threads ();
-	} catch (...) {
-		/* Destructors must not throw exceptions; anything bad
-		   happening now is too late to worry about anyway,
-		   I think.
-		*/
-	}
+	terminate_threads ();
 }
 
 void
@@ -246,6 +239,8 @@ J2KEncoder::encode (shared_ptr<PlayerVideo> pv, DCPTime time)
 void
 J2KEncoder::terminate_threads ()
 {
+	boost::this_thread::disable_interruption dis;
+
 	if (!_threads) {
 		return;
 	}
diff --git a/src/lib/job.cc b/src/lib/job.cc
index 0feda6435..d960dfaee 100644
--- a/src/lib/job.cc
+++ b/src/lib/job.cc
@@ -71,16 +71,12 @@ Job::~Job ()
 void
 Job::stop_thread ()
 {
-	if (!_thread.joinable()) {
-		return;
-	}
+	boost::this_thread::disable_interruption dis;
 
 	_thread.interrupt ();
 	try {
 		_thread.join ();
-	} catch (...) {
-		/* Too late to do anything about this */
-	}
+	} catch (...) {}
 }
 
 /** Start the job in a separate thread, returning immediately */
diff --git a/src/lib/job_manager.cc b/src/lib/job_manager.cc
index c40178f41..9eb51aee5 100644
--- a/src/lib/job_manager.cc
+++ b/src/lib/job_manager.cc
@@ -62,6 +62,8 @@ JobManager::start ()
 
 JobManager::~JobManager ()
 {
+	boost::this_thread::disable_interruption dis;
+
 	BOOST_FOREACH (boost::signals2::connection& i, _connections) {
 		i.disconnect ();
 	}
@@ -72,13 +74,9 @@ JobManager::~JobManager ()
 		_empty_condition.notify_all ();
 	}
 
-	if (_scheduler.joinable()) {
-		try {
-			_scheduler.join();
-		} catch (...) {
-
-		}
-	}
+	try {
+		_scheduler.join();
+	} catch (...) {}
 }
 
 shared_ptr<Job>
diff --git a/src/lib/update_checker.cc b/src/lib/update_checker.cc
index 82337f920..0fad330fd 100644
--- a/src/lib/update_checker.cc
+++ b/src/lib/update_checker.cc
@@ -81,19 +81,17 @@ UpdateChecker::start ()
 
 UpdateChecker::~UpdateChecker ()
 {
+	boost::this_thread::disable_interruption dis;
+
 	{
 		boost::mutex::scoped_lock lm (_process_mutex);
 		_terminate = true;
 	}
 
 	_condition.notify_all ();
-	if (_thread.joinable()) {
-		try {
-			_thread.join ();
-		} catch (...) {
-
-		}
-	}
+	try {
+		_thread.join ();
+	} catch (...) {}
 
 	curl_easy_cleanup (_curl);
 	delete[] _buffer;
diff --git a/src/lib/writer.cc b/src/lib/writer.cc
index 7d1088276..dc552e6cb 100644
--- a/src/lib/writer.cc
+++ b/src/lib/writer.cc
@@ -489,17 +489,18 @@ catch (...)
 void
 Writer::terminate_thread (bool can_throw)
 {
+	boost::this_thread::disable_interruption dis;
+
 	boost::mutex::scoped_lock lock (_state_mutex);
-	if (!_thread.joinable()) {
-		return;
-	}
 
 	_finish = true;
 	_empty_condition.notify_all ();
 	_full_condition.notify_all ();
 	lock.unlock ();
 
-	_thread.join ();
+	try {
+		_thread.join ();
+	} catch (...) {}
 
 	if (can_throw) {
 		rethrow ();