Revert of Mojo C++ bindings: support sync methods - part 2

mojo/public/cpp/bindings/lib/sync_handle_watcher.cc

Index: mojo/public/cpp/bindings/lib/sync_handle_watcher.cc
diff --git a/mojo/public/cpp/bindings/lib/sync_handle_watcher.cc b/mojo/public/cpp/bindings/lib/sync_handle_watcher.cc
deleted file mode 100644
index 197447f4a52e62f62a34ea91882a6cf26115a9a5..0000000000000000000000000000000000000000
--- a/mojo/public/cpp/bindings/lib/sync_handle_watcher.cc
+++ /dev/null
@@ -1,124 +0,0 @@
-// Copyright 2016 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 "mojo/public/cpp/bindings/lib/sync_handle_watcher.h"
-
-#include "base/lazy_instance.h"
-#include "base/logging.h"
-#include "base/stl_util.h"
-#include "base/threading/thread_local.h"
-#include "mojo/public/c/system/core.h"
-
-namespace mojo {
-namespace internal {
-namespace {
-
-base::LazyInstance<base::ThreadLocalPointer<SyncHandleWatcher>>
-    g_current_sync_handle_watcher = LAZY_INSTANCE_INITIALIZER;
-
-}  // namespace
-
-// static
-SyncHandleWatcher* SyncHandleWatcher::current() {
-  SyncHandleWatcher* result = g_current_sync_handle_watcher.Pointer()->Get();
-  if (!result) {
-    // This object will be destroyed when the current message loop goes away.
-    result = new SyncHandleWatcher();
-    DCHECK_EQ(result, g_current_sync_handle_watcher.Pointer()->Get());
-  }
-  return result;
-}
-
-bool SyncHandleWatcher::RegisterHandle(const Handle& handle,
-                                       MojoHandleSignals handle_signals,
-                                       const HandleCallback& callback) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-
-  if (ContainsKey(handles_, handle))
-    return false;
-
-  MojoResult result = MojoAddHandle(wait_set_handle_.get().value(),
-                                    handle.value(), handle_signals);
-  if (result != MOJO_RESULT_OK)
-    return false;
-
-  handles_[handle] = callback;
-  return true;
-}
-
-void SyncHandleWatcher::UnregisterHandle(const Handle& handle) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  DCHECK(ContainsKey(handles_, handle));
-
-  MojoResult result =
-      MojoRemoveHandle(wait_set_handle_.get().value(), handle.value());
-  DCHECK_EQ(MOJO_RESULT_OK, result);
-
-  handles_.erase(handle);
-}
-
-bool SyncHandleWatcher::WatchAllHandles(const Handle& caller_handle,
-                                        const bool* should_stop) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-
-  MojoResult result;
-  uint32_t num_ready_handles;
-  MojoHandle ready_handle;
-  MojoResult ready_handle_result;
-
-  while (!*should_stop) {
-    if (!ContainsKey(handles_, caller_handle))
-      return false;
-    do {
-      result = Wait(wait_set_handle_.get(), MOJO_HANDLE_SIGNAL_READABLE,
-                    MOJO_DEADLINE_INDEFINITE, nullptr);
-      if (result != MOJO_RESULT_OK)
-        return false;
-
-      // TODO(yzshen): Theoretically it can reduce sync call re-entrancy if we
-      // give priority to the handle that is waiting for sync response.
-      num_ready_handles = 1;
-      result = MojoGetReadyHandles(wait_set_handle_.get().value(),
-                                   &num_ready_handles, &ready_handle,
-                                   &ready_handle_result, nullptr);
-      if (result != MOJO_RESULT_OK && result != MOJO_RESULT_SHOULD_WAIT)
-        return false;
-    } while (result == MOJO_RESULT_SHOULD_WAIT);
-
-    const auto iter = handles_.find(Handle(ready_handle));
-    iter->second.Run(ready_handle_result);
-  };
-
-  return true;
-}
-
-SyncHandleWatcher::SyncHandleWatcher() {
-  MojoHandle handle;
-  MojoResult result = MojoCreateWaitSet(&handle);
-  CHECK_EQ(MOJO_RESULT_OK, result);
-  wait_set_handle_.reset(Handle(handle));
-  CHECK(wait_set_handle_.is_valid());
-
-  DCHECK(!g_current_sync_handle_watcher.Pointer()->Get());
-  g_current_sync_handle_watcher.Pointer()->Set(this);
-
-  base::MessageLoop::current()->AddDestructionObserver(this);
-}
-
-SyncHandleWatcher::~SyncHandleWatcher() {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  DCHECK(handles_.empty());
-  g_current_sync_handle_watcher.Pointer()->Set(nullptr);
-}
-
-void SyncHandleWatcher::WillDestroyCurrentMessageLoop() {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  DCHECK_EQ(this, g_current_sync_handle_watcher.Pointer()->Get());
-
-  base::MessageLoop::current()->RemoveDestructionObserver(this);
-  delete this;
-}
-
-}  // namespace internal
-}  // namespace mojo