net: Implement canceling of all async operations in FileStream.

net/base/file_stream_context.cc

+// 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/base/file_stream_context.h"
+
+#include "base/location.h"
+#include "base/message_loop_proxy.h"
+#include "base/task_runner_util.h"
+#include "base/threading/thread_restrictions.h"
+#include "base/threading/worker_pool.h"
+#include "net/base/file_stream_net_log_parameters.h"
+#include "net/base/net_errors.h"
+
+namespace {
+
+void CallInt64ToInt(const net::CompletionCallback& callback, int64 result) {
+  callback.Run(static_cast<int>(result));
+}
+
+}
+
+namespace net {
+
+void FileStream::Context::Orphan() {
+  DCHECK(!orphaned_);
+
+  orphaned_ = true;
+  if (file_ != base::kInvalidPlatformFileValue)
+    bound_net_log_.EndEvent(net::NetLog::TYPE_FILE_STREAM_OPEN);

[willchan no longer on Chromium, 2012/10/30 18:01:27]

No need to use net:: when within net already

+
+  if (!async_in_progress_) {
+    CloseAndDelete();
+  } else if (file_ != base::kInvalidPlatformFileValue) {
+    CancelIo(file_);
+  }
+}
+
+void FileStream::Context::OpenAsync(const FilePath& path,
+                                    int open_flags,
+                                    const CompletionCallback& callback) {
+  DCHECK(!async_in_progress_);
+
+  BeginOpenEvent(path);
+
+  const bool posted = base::PostTaskAndReplyWithResult(
+      base::WorkerPool::GetTaskRunner(true /* task_is_slow */),
+      FROM_HERE,
+      base::Bind(&Context::OpenFileImpl,
+                 base::Unretained(this), path, open_flags),
+      base::Bind(&Context::OnOpenCompleted,
+                 base::Unretained(this), callback));
+  DCHECK(posted);
+
+  async_in_progress_ = true;
+}
+
+int FileStream::Context::OpenSync(const FilePath& path, int open_flags) {
+  DCHECK(!async_in_progress_);
+
+  BeginOpenEvent(path);
+  OpenResult result = OpenFileImpl(path, open_flags);
+  file_ = result.file;
+  if (file_ == base::kInvalidPlatformFileValue) {
+    result.error_code = ProcessOpenError(result.error_code);
+  } else {
+    // TODO(satorux): Remove this once all async clients are migrated to use
+    // Open(). crbug.com/114783
+    if (open_flags & base::PLATFORM_FILE_ASYNC)
+      OnAsyncFileOpened();
+  }
+  return result.error_code;
+}
+
+void FileStream::Context::CloseSync() {
+  DCHECK(!async_in_progress_);
+  if (file_ != base::kInvalidPlatformFileValue) {
+    base::ClosePlatformFile(file_);
+    file_ = base::kInvalidPlatformFileValue;
+    bound_net_log_.EndEvent(net::NetLog::TYPE_FILE_STREAM_OPEN);
+  }
+}
+
+void FileStream::Context::SeekAsync(Whence whence,
+                                    int64 offset,
+                                    const Int64CompletionCallback& callback) {
+  DCHECK(!async_in_progress_);
+
+  const bool posted = base::PostTaskAndReplyWithResult(
+      base::WorkerPool::GetTaskRunner(true /* task is slow */),
+      FROM_HERE,
+      base::Bind(&Context::SeekFileImpl,
+                 base::Unretained(this), whence, offset),
+      base::Bind(&Context::ProcessAsyncResult,
+                 base::Unretained(this), callback, FILE_ERROR_SOURCE_SEEK));
+  DCHECK(posted);
+
+  async_in_progress_ = true;
+}
+
+int64 FileStream::Context::SeekSync(Whence whence, int64 offset) {
+  int64 result = SeekFileImpl(whence, offset);
+  CheckForIOError(&result, FILE_ERROR_SOURCE_SEEK);
+  return result;
+}
+
+void FileStream::Context::FlushAsync(const CompletionCallback& callback) {
+  DCHECK(!async_in_progress_);
+
+  const bool posted = base::PostTaskAndReplyWithResult(
+      base::WorkerPool::GetTaskRunner(true /* task is slow */),
+      FROM_HERE,
+      base::Bind(&Context::FlushFileImpl,
+                 base::Unretained(this)),
+      base::Bind(&Context::ProcessAsyncResult,
+                 base::Unretained(this), IntToInt64(callback),
+                 FILE_ERROR_SOURCE_FLUSH));
+  DCHECK(posted);
+
+  async_in_progress_ = true;
+}
+
+int FileStream::Context::FlushSync() {
+  int64 result = FlushFileImpl();
+  CheckForIOError(&result, FILE_ERROR_SOURCE_FLUSH);
+  return result;
+}
+
+int FileStream::Context::RecordAndMapError(int error,
+                                           FileErrorSource source) const {
+  // The following check is against incorrect use or bug. File descriptor
+  // shouldn't ever be closed outside of FileStream while it still tries to do
+  // something with it.
+  DCHECK(error != ERROR_BAD_FILE);
+  net::Error net_error = MapSystemError(error);
+
+  if (!orphaned_) {
+    bound_net_log_.AddEvent(net::NetLog::TYPE_FILE_STREAM_ERROR,
+                            base::Bind(&NetLogFileStreamErrorCallback,
+                                       source, error, net_error));
+  }
+  RecordFileError(error, source, record_uma_);
+  return net_error;
+}
+
+void FileStream::Context::BeginOpenEvent(const FilePath& path) {
+  std::string file_name = path.AsUTF8Unsafe();
+  bound_net_log_.BeginEvent(net::NetLog::TYPE_FILE_STREAM_OPEN,
+                            NetLog::StringCallback("file_name", &file_name));
+}
+
+FileStream::Context::OpenResult FileStream::Context::OpenFileImpl(
+    const FilePath& path, int open_flags) {
+  OpenResult result;
+  result.error_code = OK;
+  result.file = base::CreatePlatformFile(path, open_flags, NULL, NULL);
+  if (result.file == base::kInvalidPlatformFileValue)
+    result.error_code = GetLastErrno();
+
+  return result;
+}
+
+int FileStream::Context::ProcessOpenError(int error_code) {
+  bound_net_log_.EndEvent(net::NetLog::TYPE_FILE_STREAM_OPEN);
+  return RecordAndMapError(error_code, FILE_ERROR_SOURCE_OPEN);
+}
+
+void FileStream::Context::OnOpenCompleted(const CompletionCallback& callback,
+                                          OpenResult result) {
+  file_ = result.file;
+  if (file_ == base::kInvalidPlatformFileValue)
+    result.error_code = ProcessOpenError(result.error_code);
+  else if (!orphaned_)
+    OnAsyncFileOpened();
+  OnAsyncCompleted(IntToInt64(callback), result.error_code);
+}
+
+void FileStream::Context::CloseAndDelete() {
+  DCHECK(!async_in_progress_);
+
+  if (file_ == base::kInvalidPlatformFileValue) {
+    delete this;
+  } else {
+    const bool posted = base::WorkerPool::PostTaskAndReply(
+        FROM_HERE,
+        base::Bind(base::IgnoreResult(&base::ClosePlatformFile), file_),
+        base::Bind(&Context::OnCloseCompleted, base::Unretained(this)),
+        true /* task_is_slow */);
+    DCHECK(posted);
+    file_ = base::kInvalidPlatformFileValue;
+  }
+}
+
+void FileStream::Context::OnCloseCompleted() {
+  delete this;
+}
+
+Int64CompletionCallback FileStream::Context::IntToInt64(
+    const CompletionCallback& callback) {
+  return base::Bind(&CallInt64ToInt, callback);
+}
+
+void FileStream::Context::CheckForIOError(int64* result,
+                                          FileErrorSource source) {
+  if (*result < 0)
+    *result = RecordAndMapError(static_cast<int>(*result), source);
+}
+
+void FileStream::Context::ProcessAsyncResult(
+    const Int64CompletionCallback& callback,
+    FileErrorSource source,
+    int64 result) {
+  CheckForIOError(&result, source);
+  OnAsyncCompleted(callback, result);
+}
+
+void FileStream::Context::OnAsyncCompleted(
+    const Int64CompletionCallback& callback,
+    int64 result) {
+  // Reset this before Run() as Run() may issue a new async operation. Also it
+  // should be reset before CloseAsync() because it shouldn't run if any async
+  // operation is in progress.
+  async_in_progress_ = false;
+  if (orphaned_)
+    CloseAndDelete();
+  else
+    callback.Run(result);
+}
+
+}  // namespace net
+