Index: content/browser/media/midi_host.cc |
diff --git a/content/browser/media/midi_host.cc b/content/browser/media/midi_host.cc |
index 1e6de1e234f1b6b5eebdf01a97c68de307b3a139..e8fa2feb869d119f74b515a3a27449740f03f703 100644 |
--- a/content/browser/media/midi_host.cc |
+++ b/content/browser/media/midi_host.cc |
@@ -55,7 +55,8 @@ MidiHost::MidiHost(int renderer_process_id, |
midi_manager_(midi_manager), |
sent_bytes_in_flight_(0), |
bytes_sent_since_last_acknowledgement_(0), |
- output_port_count_(0) { |
+ output_port_count_(0), |
+ is_channel_closing_(false) { |
DCHECK(midi_manager_); |
} |
@@ -65,6 +66,17 @@ MidiHost::~MidiHost() { |
midi_manager_->EndSession(this); |
} |
+void MidiHost::OnChannelClosing() { |
+ // If we get here the MidiHost is going to be destroyed soon. Prevent any |
Takashi Toyoshima
2016/01/12 10:20:51
Can we fix the problem by just calling midi_manage
Oliver Chang
2016/01/12 16:38:11
Good point, I changed this to EndSession instead.
|
+ // subsequent Send() calls. |
+ // If Send() is called from a different thread (e.g. a separate thread owned |
+ // by the MidiManager implementation), it will get posted to the IO thread. |
+ // There is a race condition here if our refcount is 0 and we're about to or |
+ // have already entered OnDestruct(). |
+ base::AutoLock auto_lock(is_channel_closing_lock_); |
+ is_channel_closing_ = true; |
+} |
+ |
void MidiHost::OnDestruct() const { |
BrowserThread::DeleteOnIOThread::Destruct(this); |
} |
@@ -82,6 +94,14 @@ bool MidiHost::OnMessageReceived(const IPC::Message& message) { |
return handled; |
} |
+bool MidiHost::Send(IPC::Message* msg) { |
+ base::AutoLock auto_lock(is_channel_closing_lock_); |
+ if (!is_channel_closing_) |
+ return BrowserMessageFilter::Send(msg); |
+ |
+ return false; |
+} |
+ |
void MidiHost::OnStartSession() { |
is_session_requested_ = true; |
if (midi_manager_) |