1 files changed, 110 insertions, 0 deletions
diff --git a/chromium/net/disk_cache/blockfile/in_flight_io.cc b/chromium/net/disk_cache/blockfile/in_flight_io.cc
new file mode 100644
index 00000000000..6e9485d5f11
--- /dev/null
+++ b/chromium/net/disk_cache/blockfile/in_flight_io.cc
@@ -0,0 +1,110 @@
+// Copyright (c) 2012 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 "net/disk_cache/blockfile/in_flight_io.h"
+
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/logging.h"
+#include "base/threading/thread_restrictions.h"
+
+namespace disk_cache {
+
+BackgroundIO::BackgroundIO(InFlightIO* controller)
+    : result_(-1), io_completed_(true, false), controller_(controller) {
+}
+
+// Runs on the primary thread.
+void BackgroundIO::OnIOSignalled() {
+  if (controller_)
+    controller_->InvokeCallback(this, false);
+}
+
+void BackgroundIO::Cancel() {
+  // controller_ may be in use from the background thread at this time.
+  base::AutoLock lock(controller_lock_);
+  DCHECK(controller_);
+  controller_ = NULL;
+}
+
+BackgroundIO::~BackgroundIO() {
+}
+
+// ---------------------------------------------------------------------------
+
+InFlightIO::InFlightIO()
+    : callback_thread_(base::MessageLoopProxy::current()),
+      running_(false), single_thread_(false) {
+}
+
+InFlightIO::~InFlightIO() {
+}
+
+// Runs on the background thread.
+void BackgroundIO::NotifyController() {
+  base::AutoLock lock(controller_lock_);
+  if (controller_)
+    controller_->OnIOComplete(this);
+}
+
+void InFlightIO::WaitForPendingIO() {
+  while (!io_list_.empty()) {
+    // Block the current thread until all pending IO completes.
+    IOList::iterator it = io_list_.begin();
+    InvokeCallback(it->get(), true);
+  }
+}
+
+void InFlightIO::DropPendingIO() {
+  while (!io_list_.empty()) {
+    IOList::iterator it = io_list_.begin();
+    BackgroundIO* operation = it->get();
+    operation->Cancel();
+    DCHECK(io_list_.find(operation) != io_list_.end());
+    io_list_.erase(make_scoped_refptr(operation));
+  }
+}
+
+// Runs on a background thread.
+void InFlightIO::OnIOComplete(BackgroundIO* operation) {
+#ifndef NDEBUG
+  if (callback_thread_->BelongsToCurrentThread()) {
+    DCHECK(single_thread_ || !running_);
+    single_thread_ = true;
+  }
+#endif
+
+  callback_thread_->PostTask(FROM_HERE,
+                             base::Bind(&BackgroundIO::OnIOSignalled,
+                                        operation));
+  operation->io_completed()->Signal();
+}
+
+// Runs on the primary thread.
+void InFlightIO::InvokeCallback(BackgroundIO* operation, bool cancel_task) {
+  {
+    // http://crbug.com/74623
+    base::ThreadRestrictions::ScopedAllowWait allow_wait;
+    operation->io_completed()->Wait();
+  }
+  running_ = true;
+
+  if (cancel_task)
+    operation->Cancel();
+
+  // Make sure that we remove the operation from the list before invoking the
+  // callback (so that a subsequent cancel does not invoke the callback again).
+  DCHECK(io_list_.find(operation) != io_list_.end());
+  DCHECK(!operation->HasOneRef());
+  io_list_.erase(make_scoped_refptr(operation));
+  OnOperationComplete(operation, cancel_task);
+}
+
+// Runs on the primary thread.
+void InFlightIO::OnOperationPosted(BackgroundIO* operation) {
+  DCHECK(callback_thread_->BelongsToCurrentThread());
+  io_list_.insert(make_scoped_refptr(operation));
+}
+
+}  // namespace disk_cache