Change MessagePumpLibevent::Run to process I/O events before doing idle

base/message_pump_libevent.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/message_pump_libevent.h"
 
 #include <errno.h>
 #include <fcntl.h>
 
 #include "base/auto_reset.h"
@@ skipping 89 matching lines @@
 void MessagePumpLibevent::FileDescriptorWatcher::OnFileCanWriteWithoutBlocking(
     int fd, MessagePumpLibevent* pump) {
   pump->WillProcessIOEvent();
   watcher_->OnFileCanWriteWithoutBlocking(fd);
   pump->DidProcessIOEvent();
 }
 
 MessagePumpLibevent::MessagePumpLibevent()
     : keep_running_(true),
       in_run_(false),
+      processed_io_events_(false),
       event_base_(event_base_new()),
       wakeup_pipe_in_(-1),
       wakeup_pipe_out_(-1) {
   if (!Init())
      NOTREACHED();
 }
 
 MessagePumpLibevent::~MessagePumpLibevent() {
   DCHECK(wakeup_event_);
   DCHECK(event_base_);
@@ skipping 99 matching lines @@
   // Instead, make our own timer and reuse it on each call to event_base_loop().
   scoped_ptr<event> timer_event(new event);
 
   for (;;) {
     mac::ScopedNSAutoreleasePool autorelease_pool;
 
     bool did_work = delegate->DoWork();
     if (!keep_running_)
       break;
 
+    event_base_loop(event_base_, EVLOOP_NONBLOCK);
+    did_work |= processed_io_events_;
+    processed_io_events_ = false;
+    if (!keep_running_)

[Mark Mentovai, 2011/06/30 22:07:16]

I was wondering about this. I should have spoken up.

+      break;
+
     did_work |= delegate->DoDelayedWork(&delayed_work_time_);
     if (!keep_running_)
       break;
 
     if (did_work)
       continue;
 
     did_work = delegate->DoIdleWork();
     if (!keep_running_)
       break;
@@ skipping 49 matching lines @@
   // record of how long to sleep when we do sleep.
   delayed_work_time_ = delayed_work_time;
 }
 
 void MessagePumpLibevent::WillProcessIOEvent() {
   FOR_EACH_OBSERVER(IOObserver, io_observers_, WillProcessIOEvent());
 }
 
 void MessagePumpLibevent::DidProcessIOEvent() {
   FOR_EACH_OBSERVER(IOObserver, io_observers_, DidProcessIOEvent());
+  processed_io_events_ = true;
 }
 
 bool MessagePumpLibevent::Init() {
   int fds[2];
   if (pipe(fds)) {
     DLOG(ERROR) << "pipe() failed, errno: " << errno;
     return false;
   }
   if (SetNonBlocking(fds[0])) {
     DLOG(ERROR) << "SetNonBlocking for pipe fd[0] failed, errno: " << errno;
@@ skipping 36 matching lines @@
 // static
 void MessagePumpLibevent::OnWakeup(int socket, short flags, void* context) {
   base::MessagePumpLibevent* that =
               static_cast<base::MessagePumpLibevent*>(context);
   DCHECK(that->wakeup_pipe_out_ == socket);
 
   // Remove and discard the wakeup byte.
   char buf;
   int nread = HANDLE_EINTR(read(socket, &buf, 1));
   DCHECK_EQ(nread, 1);
+  that->processed_io_events_ = true;
   // Tell libevent to break out of inner loop.
   event_base_loopbreak(that->event_base_);
 }
 
 }  // namespace base