Move file_util_proxy to base/files.

BUG=

Review URL: https://codereview.chromium.org/12035111

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@178952 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: cf7405ff9dd49a6adf3c481f3cb439184bcc7f80
diff --git a/base/files/file_util_proxy.cc b/base/files/file_util_proxy.cc
new file mode 100644
index 0000000..f18d52b
--- /dev/null
+++ b/base/files/file_util_proxy.cc
@@ -0,0 +1,426 @@
+// 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 "base/files/file_util_proxy.h"
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/file_util.h"
+#include "base/location.h"
+#include "base/message_loop_proxy.h"
+#include "base/task_runner.h"
+#include "base/task_runner_util.h"
+
+namespace base {
+
+namespace {
+
+void CallWithTranslatedParameter(const FileUtilProxy::StatusCallback& callback,
+                                 bool value) {
+  DCHECK(!callback.is_null());
+  callback.Run(value ? PLATFORM_FILE_OK : PLATFORM_FILE_ERROR_FAILED);
+}
+
+// Helper classes or routines for individual methods.
+class CreateOrOpenHelper {
+ public:
+  CreateOrOpenHelper(TaskRunner* task_runner,
+                     const FileUtilProxy::CloseTask& close_task)
+      : task_runner_(task_runner),
+        close_task_(close_task),
+        file_handle_(kInvalidPlatformFileValue),
+        created_(false),
+        error_(PLATFORM_FILE_OK) {}
+
+  ~CreateOrOpenHelper() {
+    if (file_handle_ != kInvalidPlatformFileValue) {
+      task_runner_->PostTask(
+          FROM_HERE,
+          base::Bind(base::IgnoreResult(close_task_), file_handle_));
+    }
+  }
+
+  void RunWork(const FileUtilProxy::CreateOrOpenTask& task) {
+    error_ = task.Run(&file_handle_, &created_);
+  }
+
+  void Reply(const FileUtilProxy::CreateOrOpenCallback& callback) {
+    DCHECK(!callback.is_null());
+    callback.Run(error_, PassPlatformFile(&file_handle_), created_);
+  }
+
+ private:
+  scoped_refptr<TaskRunner> task_runner_;
+  FileUtilProxy::CloseTask close_task_;
+  PlatformFile file_handle_;
+  bool created_;
+  PlatformFileError error_;
+  DISALLOW_COPY_AND_ASSIGN(CreateOrOpenHelper);
+};
+
+class CreateTemporaryHelper {
+ public:
+  explicit CreateTemporaryHelper(TaskRunner* task_runner)
+      : task_runner_(task_runner),
+        file_handle_(kInvalidPlatformFileValue),
+        error_(PLATFORM_FILE_OK) {}
+
+  ~CreateTemporaryHelper() {
+    if (file_handle_ != kInvalidPlatformFileValue) {
+      FileUtilProxy::Close(task_runner_, file_handle_,
+                           FileUtilProxy::StatusCallback());
+    }
+  }
+
+  void RunWork(int additional_file_flags) {
+    // TODO(darin): file_util should have a variant of CreateTemporaryFile
+    // that returns a FilePath and a PlatformFile.
+    file_util::CreateTemporaryFile(&file_path_);
+
+    int file_flags =
+        PLATFORM_FILE_WRITE |
+        PLATFORM_FILE_TEMPORARY |
+        PLATFORM_FILE_CREATE_ALWAYS |
+        additional_file_flags;
+
+    error_ = PLATFORM_FILE_OK;
+    file_handle_ = CreatePlatformFile(file_path_, file_flags, NULL, &error_);
+  }
+
+  void Reply(const FileUtilProxy::CreateTemporaryCallback& callback) {
+    DCHECK(!callback.is_null());
+    callback.Run(error_, PassPlatformFile(&file_handle_), file_path_);
+  }
+
+ private:
+  scoped_refptr<TaskRunner> task_runner_;
+  PlatformFile file_handle_;
+  FilePath file_path_;
+  PlatformFileError error_;
+  DISALLOW_COPY_AND_ASSIGN(CreateTemporaryHelper);
+};
+
+class GetFileInfoHelper {
+ public:
+  GetFileInfoHelper()
+      : error_(PLATFORM_FILE_OK) {}
+
+  void RunWorkForFilePath(const FilePath& file_path) {
+    if (!file_util::PathExists(file_path)) {
+      error_ = PLATFORM_FILE_ERROR_NOT_FOUND;
+      return;
+    }
+    if (!file_util::GetFileInfo(file_path, &file_info_))
+      error_ = PLATFORM_FILE_ERROR_FAILED;
+  }
+
+  void RunWorkForPlatformFile(PlatformFile file) {
+    if (!GetPlatformFileInfo(file, &file_info_))
+      error_ = PLATFORM_FILE_ERROR_FAILED;
+  }
+
+  void Reply(const FileUtilProxy::GetFileInfoCallback& callback) {
+    if (!callback.is_null()) {
+      callback.Run(error_, file_info_);
+    }
+  }
+
+ private:
+  PlatformFileError error_;
+  PlatformFileInfo file_info_;
+  DISALLOW_COPY_AND_ASSIGN(GetFileInfoHelper);
+};
+
+class ReadHelper {
+ public:
+  explicit ReadHelper(int bytes_to_read)
+      : buffer_(new char[bytes_to_read]),
+        bytes_to_read_(bytes_to_read),
+        bytes_read_(0) {}
+
+  void RunWork(PlatformFile file, int64 offset) {
+    bytes_read_ = ReadPlatformFile(file, offset, buffer_.get(), bytes_to_read_);
+  }
+
+  void Reply(const FileUtilProxy::ReadCallback& callback) {
+    if (!callback.is_null()) {
+      PlatformFileError error =
+          (bytes_read_ < 0) ? PLATFORM_FILE_ERROR_FAILED : PLATFORM_FILE_OK;
+      callback.Run(error, buffer_.get(), bytes_read_);
+    }
+  }
+
+ private:
+  scoped_ptr<char[]> buffer_;
+  int bytes_to_read_;
+  int bytes_read_;
+  DISALLOW_COPY_AND_ASSIGN(ReadHelper);
+};
+
+class WriteHelper {
+ public:
+  WriteHelper(const char* buffer, int bytes_to_write)
+      : buffer_(new char[bytes_to_write]),
+        bytes_to_write_(bytes_to_write),
+        bytes_written_(0) {
+    memcpy(buffer_.get(), buffer, bytes_to_write);
+  }
+
+  void RunWork(PlatformFile file, int64 offset) {
+    bytes_written_ = WritePlatformFile(file, offset, buffer_.get(),
+                                       bytes_to_write_);
+  }
+
+  void Reply(const FileUtilProxy::WriteCallback& callback) {
+    if (!callback.is_null()) {
+      PlatformFileError error =
+          (bytes_written_ < 0) ? PLATFORM_FILE_ERROR_FAILED : PLATFORM_FILE_OK;
+      callback.Run(error, bytes_written_);
+    }
+  }
+
+ private:
+  scoped_ptr<char[]> buffer_;
+  int bytes_to_write_;
+  int bytes_written_;
+  DISALLOW_COPY_AND_ASSIGN(WriteHelper);
+};
+
+
+PlatformFileError CreateOrOpenAdapter(
+    const FilePath& file_path, int file_flags,
+    PlatformFile* file_handle, bool* created) {
+  DCHECK(file_handle);
+  DCHECK(created);
+  if (!file_util::DirectoryExists(file_path.DirName())) {
+    // If its parent does not exist, should return NOT_FOUND error.
+    return PLATFORM_FILE_ERROR_NOT_FOUND;
+  }
+  PlatformFileError error = PLATFORM_FILE_OK;
+  *file_handle = CreatePlatformFile(file_path, file_flags, created, &error);
+  return error;
+}
+
+PlatformFileError CloseAdapter(PlatformFile file_handle) {
+  if (!ClosePlatformFile(file_handle)) {
+    return PLATFORM_FILE_ERROR_FAILED;
+  }
+  return PLATFORM_FILE_OK;
+}
+
+PlatformFileError DeleteAdapter(const FilePath& file_path, bool recursive) {
+  if (!file_util::PathExists(file_path)) {
+    return PLATFORM_FILE_ERROR_NOT_FOUND;
+  }
+  if (!file_util::Delete(file_path, recursive)) {
+    if (!recursive && !file_util::IsDirectoryEmpty(file_path)) {
+      return PLATFORM_FILE_ERROR_NOT_EMPTY;
+    }
+    return PLATFORM_FILE_ERROR_FAILED;
+  }
+  return PLATFORM_FILE_OK;
+}
+
+}  // namespace
+
+// static
+bool FileUtilProxy::CreateOrOpen(
+    TaskRunner* task_runner,
+    const FilePath& file_path, int file_flags,
+    const CreateOrOpenCallback& callback) {
+  return RelayCreateOrOpen(
+      task_runner,
+      base::Bind(&CreateOrOpenAdapter, file_path, file_flags),
+      base::Bind(&CloseAdapter),
+      callback);
+}
+
+// static
+bool FileUtilProxy::CreateTemporary(
+    TaskRunner* task_runner,
+    int additional_file_flags,
+    const CreateTemporaryCallback& callback) {
+  CreateTemporaryHelper* helper = new CreateTemporaryHelper(task_runner);
+  return task_runner->PostTaskAndReply(
+      FROM_HERE,
+      Bind(&CreateTemporaryHelper::RunWork, Unretained(helper),
+           additional_file_flags),
+      Bind(&CreateTemporaryHelper::Reply, Owned(helper), callback));
+}
+
+// static
+bool FileUtilProxy::Close(
+    TaskRunner* task_runner,
+    base::PlatformFile file_handle,
+    const StatusCallback& callback) {
+  return RelayClose(
+      task_runner,
+      base::Bind(&CloseAdapter),
+      file_handle, callback);
+}
+
+// Retrieves the information about a file. It is invalid to pass NULL for the
+// callback.
+bool FileUtilProxy::GetFileInfo(
+    TaskRunner* task_runner,
+    const FilePath& file_path,
+    const GetFileInfoCallback& callback) {
+  GetFileInfoHelper* helper = new GetFileInfoHelper;
+  return task_runner->PostTaskAndReply(
+      FROM_HERE,
+      Bind(&GetFileInfoHelper::RunWorkForFilePath,
+           Unretained(helper), file_path),
+      Bind(&GetFileInfoHelper::Reply, Owned(helper), callback));
+}
+
+// static
+bool FileUtilProxy::GetFileInfoFromPlatformFile(
+    TaskRunner* task_runner,
+    PlatformFile file,
+    const GetFileInfoCallback& callback) {
+  GetFileInfoHelper* helper = new GetFileInfoHelper;
+  return task_runner->PostTaskAndReply(
+      FROM_HERE,
+      Bind(&GetFileInfoHelper::RunWorkForPlatformFile,
+           Unretained(helper), file),
+      Bind(&GetFileInfoHelper::Reply, Owned(helper), callback));
+}
+
+// static
+bool FileUtilProxy::Delete(TaskRunner* task_runner,
+                           const FilePath& file_path,
+                           bool recursive,
+                           const StatusCallback& callback) {
+  return base::PostTaskAndReplyWithResult(
+      task_runner, FROM_HERE,
+      Bind(&DeleteAdapter, file_path, recursive),
+      callback);
+}
+
+// static
+bool FileUtilProxy::RecursiveDelete(
+    TaskRunner* task_runner,
+    const FilePath& file_path,
+    const StatusCallback& callback) {
+  return base::PostTaskAndReplyWithResult(
+      task_runner, FROM_HERE,
+      Bind(&DeleteAdapter, file_path, true /* recursive */),
+      callback);
+}
+
+// static
+bool FileUtilProxy::Read(
+    TaskRunner* task_runner,
+    PlatformFile file,
+    int64 offset,
+    int bytes_to_read,
+    const ReadCallback& callback) {
+  if (bytes_to_read < 0) {
+    return false;
+  }
+  ReadHelper* helper = new ReadHelper(bytes_to_read);
+  return task_runner->PostTaskAndReply(
+      FROM_HERE,
+      Bind(&ReadHelper::RunWork, Unretained(helper), file, offset),
+      Bind(&ReadHelper::Reply, Owned(helper), callback));
+}
+
+// static
+bool FileUtilProxy::Write(
+    TaskRunner* task_runner,
+    PlatformFile file,
+    int64 offset,
+    const char* buffer,
+    int bytes_to_write,
+    const WriteCallback& callback) {
+  if (bytes_to_write <= 0 || buffer == NULL) {
+    return false;
+  }
+  WriteHelper* helper = new WriteHelper(buffer, bytes_to_write);
+  return task_runner->PostTaskAndReply(
+      FROM_HERE,
+      Bind(&WriteHelper::RunWork, Unretained(helper), file, offset),
+      Bind(&WriteHelper::Reply, Owned(helper), callback));
+}
+
+// static
+bool FileUtilProxy::Touch(
+    TaskRunner* task_runner,
+    PlatformFile file,
+    const Time& last_access_time,
+    const Time& last_modified_time,
+    const StatusCallback& callback) {
+  return base::PostTaskAndReplyWithResult(
+      task_runner,
+      FROM_HERE,
+      Bind(&TouchPlatformFile, file,
+           last_access_time, last_modified_time),
+      Bind(&CallWithTranslatedParameter, callback));
+}
+
+// static
+bool FileUtilProxy::Touch(
+    TaskRunner* task_runner,
+    const FilePath& file_path,
+    const Time& last_access_time,
+    const Time& last_modified_time,
+    const StatusCallback& callback) {
+  return base::PostTaskAndReplyWithResult(
+      task_runner,
+      FROM_HERE,
+      Bind(&file_util::TouchFile, file_path,
+           last_access_time, last_modified_time),
+      Bind(&CallWithTranslatedParameter, callback));
+}
+
+// static
+bool FileUtilProxy::Truncate(
+    TaskRunner* task_runner,
+    PlatformFile file,
+    int64 length,
+    const StatusCallback& callback) {
+  return base::PostTaskAndReplyWithResult(
+      task_runner,
+      FROM_HERE,
+      Bind(&TruncatePlatformFile, file, length),
+      Bind(&CallWithTranslatedParameter, callback));
+}
+
+// static
+bool FileUtilProxy::Flush(
+    TaskRunner* task_runner,
+    PlatformFile file,
+    const StatusCallback& callback) {
+  return base::PostTaskAndReplyWithResult(
+      task_runner,
+      FROM_HERE,
+      Bind(&FlushPlatformFile, file),
+      Bind(&CallWithTranslatedParameter, callback));
+}
+
+// static
+bool FileUtilProxy::RelayCreateOrOpen(
+    TaskRunner* task_runner,
+    const CreateOrOpenTask& open_task,
+    const CloseTask& close_task,
+    const CreateOrOpenCallback& callback) {
+  CreateOrOpenHelper* helper = new CreateOrOpenHelper(
+      task_runner, close_task);
+  return task_runner->PostTaskAndReply(
+      FROM_HERE,
+      Bind(&CreateOrOpenHelper::RunWork, Unretained(helper), open_task),
+      Bind(&CreateOrOpenHelper::Reply, Owned(helper), callback));
+}
+
+// static
+bool FileUtilProxy::RelayClose(
+    TaskRunner* task_runner,
+    const CloseTask& close_task,
+    PlatformFile file_handle,
+    const StatusCallback& callback) {
+  return base::PostTaskAndReplyWithResult(
+      task_runner, FROM_HERE, Bind(close_task, file_handle), callback);
+}
+
+}  // namespace base
diff --git a/base/files/file_util_proxy.h b/base/files/file_util_proxy.h
new file mode 100644
index 0000000..8cbdfcb
--- /dev/null
+++ b/base/files/file_util_proxy.h
@@ -0,0 +1,211 @@
+// 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.
+
+#ifndef BASE_FILES_FILE_UTIL_PROXY_H_
+#define BASE_FILES_FILE_UTIL_PROXY_H_
+
+#include "base/base_export.h"
+#include "base/callback_forward.h"
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/memory/ref_counted.h"
+#include "base/platform_file.h"
+
+namespace tracked_objects {
+class Location;
+};
+
+namespace base {
+
+class TaskRunner;
+class Time;
+
+// This class provides asynchronous access to common file routines.
+class BASE_EXPORT FileUtilProxy {
+ public:
+  // Holds metadata for file or directory entry.
+  struct Entry {
+    FilePath::StringType name;
+    bool is_directory;
+    int64 size;
+    base::Time last_modified_time;
+  };
+
+  // This callback is used by methods that report only an error code.  It is
+  // valid to pass a null callback to any function that takes a StatusCallback,
+  // in which case the operation will complete silently.
+  typedef Callback<void(PlatformFileError)> StatusCallback;
+
+  typedef Callback<void(PlatformFileError,
+                        PassPlatformFile,
+                        bool /* created */)> CreateOrOpenCallback;
+  typedef Callback<void(PlatformFileError,
+                        PassPlatformFile,
+                        const FilePath&)> CreateTemporaryCallback;
+  typedef Callback<void(PlatformFileError,
+                        const PlatformFileInfo&)> GetFileInfoCallback;
+  typedef Callback<void(PlatformFileError,
+                        const char* /* data */,
+                        int /* bytes read */)> ReadCallback;
+  typedef Callback<void(PlatformFileError,
+                        int /* bytes written */)> WriteCallback;
+
+  typedef Callback<PlatformFileError(PlatformFile*, bool*)> CreateOrOpenTask;
+  typedef Callback<PlatformFileError(PlatformFile)> CloseTask;
+  typedef Callback<PlatformFileError(void)> FileTask;
+
+  // Creates or opens a file with the given flags. It is invalid to pass a null
+  // callback. If PLATFORM_FILE_CREATE is set in |file_flags| it always tries to
+  // create a new file at the given |file_path| and calls back with
+  // PLATFORM_FILE_ERROR_FILE_EXISTS if the |file_path| already exists.
+  //
+  // This returns false if task posting to |task_runner| has failed.
+  static bool CreateOrOpen(TaskRunner* task_runner,
+                           const FilePath& file_path,
+                           int file_flags,
+                           const CreateOrOpenCallback& callback);
+
+  // Creates a temporary file for writing. The path and an open file handle are
+  // returned. It is invalid to pass a null callback. The additional file flags
+  // will be added on top of the default file flags which are:
+  //   base::PLATFORM_FILE_CREATE_ALWAYS
+  //   base::PLATFORM_FILE_WRITE
+  //   base::PLATFORM_FILE_TEMPORARY.
+  // Set |additional_file_flags| to 0 for synchronous writes and set to
+  // base::PLATFORM_FILE_ASYNC to support asynchronous file operations.
+  //
+  // This returns false if task posting to |task_runner| has failed.
+  static bool CreateTemporary(
+      TaskRunner* task_runner,
+      int additional_file_flags,
+      const CreateTemporaryCallback& callback);
+
+  // Close the given file handle.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool Close(TaskRunner* task_runner,
+                    PlatformFile,
+                    const StatusCallback& callback);
+
+  // Retrieves the information about a file. It is invalid to pass a null
+  // callback.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool GetFileInfo(
+      TaskRunner* task_runner,
+      const FilePath& file_path,
+      const GetFileInfoCallback& callback);
+
+  // Does the same as GetFileInfo but takes PlatformFile instead of FilePath.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool GetFileInfoFromPlatformFile(
+      TaskRunner* task_runner,
+      PlatformFile file,
+      const GetFileInfoCallback& callback);
+
+  // Deletes a file or a directory.
+  // It is an error to delete a non-empty directory with recursive=false.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool Delete(TaskRunner* task_runner,
+                     const FilePath& file_path,
+                     bool recursive,
+                     const StatusCallback& callback);
+
+  // Deletes a directory and all of its contents.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool RecursiveDelete(
+      TaskRunner* task_runner,
+      const FilePath& file_path,
+      const StatusCallback& callback);
+
+  // Reads from a file. On success, the file pointer is moved to position
+  // |offset + bytes_to_read| in the file. The callback can be null.
+  //
+  // This returns false if |bytes_to_read| is less than zero, or
+  // if task posting to |task_runner| has failed.
+  static bool Read(
+      TaskRunner* task_runner,
+      PlatformFile file,
+      int64 offset,
+      int bytes_to_read,
+      const ReadCallback& callback);
+
+  // Writes to a file. If |offset| is greater than the length of the file,
+  // |false| is returned. On success, the file pointer is moved to position
+  // |offset + bytes_to_write| in the file. The callback can be null.
+  // |bytes_to_write| must be greater than zero.
+  //
+  // This returns false if |bytes_to_write| is less than or equal to zero,
+  // if |buffer| is NULL, or if task posting to |task_runner| has failed.
+  static bool Write(
+      TaskRunner* task_runner,
+      PlatformFile file,
+      int64 offset,
+      const char* buffer,
+      int bytes_to_write,
+      const WriteCallback& callback);
+
+  // Touches a file. The callback can be null.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool Touch(
+      TaskRunner* task_runner,
+      PlatformFile file,
+      const Time& last_access_time,
+      const Time& last_modified_time,
+      const StatusCallback& callback);
+
+  // Touches a file. The callback can be null.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool Touch(
+      TaskRunner* task_runner,
+      const FilePath& file_path,
+      const Time& last_access_time,
+      const Time& last_modified_time,
+      const StatusCallback& callback);
+
+  // Truncates a file to the given length. If |length| is greater than the
+  // current length of the file, the file will be extended with zeroes.
+  // The callback can be null.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool Truncate(
+      TaskRunner* task_runner,
+      PlatformFile file,
+      int64 length,
+      const StatusCallback& callback);
+
+  // Truncates a file to the given length. If |length| is greater than the
+  // current length of the file, the file will be extended with zeroes.
+  // The callback can be null.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool Truncate(
+      TaskRunner* task_runner,
+      const FilePath& path,
+      int64 length,
+      const StatusCallback& callback);
+
+  // Flushes a file. The callback can be null.
+  // This returns false if task posting to |task_runner| has failed.
+  static bool Flush(
+      TaskRunner* task_runner,
+      PlatformFile file,
+      const StatusCallback& callback);
+
+  // Relay helpers.
+  // They return false if posting a given task to |task_runner| has failed.
+  static bool RelayCreateOrOpen(
+      TaskRunner* task_runner,
+      const CreateOrOpenTask& open_task,
+      const CloseTask& close_task,
+      const CreateOrOpenCallback& callback);
+  static bool RelayClose(
+      TaskRunner* task_runner,
+      const CloseTask& close_task,
+      PlatformFile,
+      const StatusCallback& callback);
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(FileUtilProxy);
+};
+
+}  // namespace base
+
+#endif  // BASE_FILES_FILE_UTIL_PROXY_H_
diff --git a/base/files/file_util_proxy_unittest.cc b/base/files/file_util_proxy_unittest.cc
new file mode 100644
index 0000000..447c43b
--- /dev/null
+++ b/base/files/file_util_proxy_unittest.cc
@@ -0,0 +1,410 @@
+// 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 "base/files/file_util_proxy.h"
+
+#include <map>
+
+#include "base/bind.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/logging.h"
+#include "base/memory/weak_ptr.h"
+#include "base/message_loop.h"
+#include "base/platform_file.h"
+#include "base/threading/thread.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace base {
+
+class FileUtilProxyTest : public testing::Test {
+ public:
+  FileUtilProxyTest()
+      : message_loop_(MessageLoop::TYPE_IO),
+        file_thread_("FileUtilProxyTestFileThread"),
+        error_(PLATFORM_FILE_OK),
+        created_(false),
+        file_(kInvalidPlatformFileValue),
+        bytes_written_(-1),
+        weak_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)) {}
+
+  virtual void SetUp() OVERRIDE {
+    ASSERT_TRUE(dir_.CreateUniqueTempDir());
+    ASSERT_TRUE(file_thread_.Start());
+  }
+
+  virtual void TearDown() OVERRIDE {
+    if (file_ != kInvalidPlatformFileValue)
+      ClosePlatformFile(file_);
+  }
+
+  void DidFinish(PlatformFileError error) {
+    error_ = error;
+    MessageLoop::current()->QuitWhenIdle();
+  }
+
+  void DidCreateOrOpen(PlatformFileError error,
+                       PassPlatformFile file,
+                       bool created) {
+    error_ = error;
+    file_ = file.ReleaseValue();
+    created_ = created;
+    MessageLoop::current()->QuitWhenIdle();
+  }
+
+  void DidCreateTemporary(PlatformFileError error,
+                          PassPlatformFile file,
+                          const FilePath& path) {
+    error_ = error;
+    file_ = file.ReleaseValue();
+    path_ = path;
+    MessageLoop::current()->QuitWhenIdle();
+  }
+
+  void DidGetFileInfo(PlatformFileError error,
+                      const PlatformFileInfo& file_info) {
+    error_ = error;
+    file_info_ = file_info;
+    MessageLoop::current()->QuitWhenIdle();
+  }
+
+  void DidRead(PlatformFileError error,
+               const char* data,
+               int bytes_read) {
+    error_ = error;
+    buffer_.resize(bytes_read);
+    memcpy(&buffer_[0], data, bytes_read);
+    MessageLoop::current()->QuitWhenIdle();
+  }
+
+  void DidWrite(PlatformFileError error,
+                int bytes_written) {
+    error_ = error;
+    bytes_written_ = bytes_written;
+    MessageLoop::current()->QuitWhenIdle();
+  }
+
+ protected:
+  PlatformFile GetTestPlatformFile(int flags) {
+    if (file_ != kInvalidPlatformFileValue)
+      return file_;
+    bool created;
+    PlatformFileError error;
+    file_ = CreatePlatformFile(test_path(), flags, &created, &error);
+    EXPECT_EQ(PLATFORM_FILE_OK, error);
+    EXPECT_NE(kInvalidPlatformFileValue, file_);
+    return file_;
+  }
+
+  TaskRunner* file_task_runner() const {
+    return file_thread_.message_loop_proxy().get();
+  }
+  const FilePath& test_dir_path() const { return dir_.path(); }
+  const FilePath test_path() const { return dir_.path().AppendASCII("test"); }
+
+  MessageLoop message_loop_;
+  Thread file_thread_;
+
+  ScopedTempDir dir_;
+  PlatformFileError error_;
+  bool created_;
+  PlatformFile file_;
+  FilePath path_;
+  PlatformFileInfo file_info_;
+  std::vector<char> buffer_;
+  int bytes_written_;
+  WeakPtrFactory<FileUtilProxyTest> weak_factory_;
+};
+
+TEST_F(FileUtilProxyTest, CreateOrOpen_Create) {
+  FileUtilProxy::CreateOrOpen(
+      file_task_runner(),
+      test_path(),
+      PLATFORM_FILE_CREATE | PLATFORM_FILE_READ,
+      Bind(&FileUtilProxyTest::DidCreateOrOpen, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+  EXPECT_TRUE(created_);
+  EXPECT_NE(kInvalidPlatformFileValue, file_);
+  EXPECT_TRUE(file_util::PathExists(test_path()));
+}
+
+TEST_F(FileUtilProxyTest, CreateOrOpen_Open) {
+  // Creates a file.
+  file_util::WriteFile(test_path(), NULL, 0);
+  ASSERT_TRUE(file_util::PathExists(test_path()));
+
+  // Opens the created file.
+  FileUtilProxy::CreateOrOpen(
+      file_task_runner(),
+      test_path(),
+      PLATFORM_FILE_OPEN | PLATFORM_FILE_READ,
+      Bind(&FileUtilProxyTest::DidCreateOrOpen, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+  EXPECT_FALSE(created_);
+  EXPECT_NE(kInvalidPlatformFileValue, file_);
+}
+
+TEST_F(FileUtilProxyTest, CreateOrOpen_OpenNonExistent) {
+  FileUtilProxy::CreateOrOpen(
+      file_task_runner(),
+      test_path(),
+      PLATFORM_FILE_OPEN | PLATFORM_FILE_READ,
+      Bind(&FileUtilProxyTest::DidCreateOrOpen, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+  EXPECT_EQ(PLATFORM_FILE_ERROR_NOT_FOUND, error_);
+  EXPECT_FALSE(created_);
+  EXPECT_EQ(kInvalidPlatformFileValue, file_);
+  EXPECT_FALSE(file_util::PathExists(test_path()));
+}
+
+TEST_F(FileUtilProxyTest, Close) {
+  // Creates a file.
+  PlatformFile file = GetTestPlatformFile(
+      PLATFORM_FILE_CREATE | PLATFORM_FILE_WRITE);
+
+#if defined(OS_WIN)
+  // This fails on Windows if the file is not closed.
+  EXPECT_FALSE(file_util::Move(test_path(),
+                               test_dir_path().AppendASCII("new")));
+#endif
+
+  FileUtilProxy::Close(
+      file_task_runner(),
+      file,
+      Bind(&FileUtilProxyTest::DidFinish, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+
+  // Now it should pass on all platforms.
+  EXPECT_TRUE(file_util::Move(test_path(), test_dir_path().AppendASCII("new")));
+}
+
+TEST_F(FileUtilProxyTest, CreateTemporary) {
+  FileUtilProxy::CreateTemporary(
+      file_task_runner(), 0 /* additional_file_flags */,
+      Bind(&FileUtilProxyTest::DidCreateTemporary, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+  EXPECT_TRUE(file_util::PathExists(path_));
+  EXPECT_NE(kInvalidPlatformFileValue, file_);
+
+  // The file should be writable.
+#if defined(OS_WIN)
+   HANDLE hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
+   OVERLAPPED overlapped = {0};
+   overlapped.hEvent = hEvent;
+   DWORD bytes_written;
+   if (!::WriteFile(file_, "test", 4, &bytes_written, &overlapped)) {
+     // Temporary file is created with ASYNC flag, so WriteFile may return 0
+     // with ERROR_IO_PENDING.
+     EXPECT_EQ(ERROR_IO_PENDING, GetLastError());
+     GetOverlappedResult(file_, &overlapped, &bytes_written, TRUE);
+   }
+   EXPECT_EQ(4, bytes_written);
+#else
+  // On POSIX ASYNC flag does not affect synchronous read/write behavior.
+  EXPECT_EQ(4, WritePlatformFile(file_, 0, "test", 4));
+#endif
+  EXPECT_TRUE(ClosePlatformFile(file_));
+  file_ = kInvalidPlatformFileValue;
+
+  // Make sure the written data can be read from the returned path.
+  std::string data;
+  EXPECT_TRUE(file_util::ReadFileToString(path_, &data));
+  EXPECT_EQ("test", data);
+
+  // Make sure we can & do delete the created file to prevent leaks on the bots.
+  EXPECT_TRUE(file_util::Delete(path_, false));
+}
+
+TEST_F(FileUtilProxyTest, GetFileInfo_File) {
+  // Setup.
+  ASSERT_EQ(4, file_util::WriteFile(test_path(), "test", 4));
+  PlatformFileInfo expected_info;
+  file_util::GetFileInfo(test_path(), &expected_info);
+
+  // Run.
+  FileUtilProxy::GetFileInfo(
+      file_task_runner(),
+      test_path(),
+      Bind(&FileUtilProxyTest::DidGetFileInfo, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+
+  // Verify.
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+  EXPECT_EQ(expected_info.size, file_info_.size);
+  EXPECT_EQ(expected_info.is_directory, file_info_.is_directory);
+  EXPECT_EQ(expected_info.is_symbolic_link, file_info_.is_symbolic_link);
+  EXPECT_EQ(expected_info.last_modified, file_info_.last_modified);
+  EXPECT_EQ(expected_info.last_accessed, file_info_.last_accessed);
+  EXPECT_EQ(expected_info.creation_time, file_info_.creation_time);
+}
+
+TEST_F(FileUtilProxyTest, GetFileInfo_Directory) {
+  // Setup.
+  ASSERT_TRUE(file_util::CreateDirectory(test_path()));
+  PlatformFileInfo expected_info;
+  file_util::GetFileInfo(test_path(), &expected_info);
+
+  // Run.
+  FileUtilProxy::GetFileInfo(
+      file_task_runner(),
+      test_path(),
+      Bind(&FileUtilProxyTest::DidGetFileInfo, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+
+  // Verify.
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+  EXPECT_EQ(expected_info.size, file_info_.size);
+  EXPECT_EQ(expected_info.is_directory, file_info_.is_directory);
+  EXPECT_EQ(expected_info.is_symbolic_link, file_info_.is_symbolic_link);
+  EXPECT_EQ(expected_info.last_modified, file_info_.last_modified);
+  EXPECT_EQ(expected_info.last_accessed, file_info_.last_accessed);
+  EXPECT_EQ(expected_info.creation_time, file_info_.creation_time);
+}
+
+TEST_F(FileUtilProxyTest, Read) {
+  // Setup.
+  const char expected_data[] = "bleh";
+  int expected_bytes = arraysize(expected_data);
+  ASSERT_EQ(expected_bytes,
+            file_util::WriteFile(test_path(), expected_data, expected_bytes));
+
+  // Run.
+  FileUtilProxy::Read(
+      file_task_runner(),
+      GetTestPlatformFile(PLATFORM_FILE_OPEN | PLATFORM_FILE_READ),
+      0,  // offset
+      128,
+      Bind(&FileUtilProxyTest::DidRead, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+
+  // Verify.
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+  EXPECT_EQ(expected_bytes, static_cast<int>(buffer_.size()));
+  for (size_t i = 0; i < buffer_.size(); ++i) {
+    EXPECT_EQ(expected_data[i], buffer_[i]);
+  }
+}
+
+TEST_F(FileUtilProxyTest, WriteAndFlush) {
+  const char data[] = "foo!";
+  int data_bytes = ARRAYSIZE_UNSAFE(data);
+  PlatformFile file = GetTestPlatformFile(
+      PLATFORM_FILE_CREATE | PLATFORM_FILE_WRITE);
+
+  FileUtilProxy::Write(
+      file_task_runner(),
+      file,
+      0,  // offset
+      data,
+      data_bytes,
+      Bind(&FileUtilProxyTest::DidWrite, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+  EXPECT_EQ(data_bytes, bytes_written_);
+
+  // Flush the written data.  (So that the following read should always
+  // succeed.  On some platforms it may work with or without this flush.)
+  FileUtilProxy::Flush(
+      file_task_runner(),
+      file,
+      Bind(&FileUtilProxyTest::DidFinish, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+
+  // Verify the written data.
+  char buffer[10];
+  EXPECT_EQ(data_bytes, file_util::ReadFile(test_path(), buffer, data_bytes));
+  for (int i = 0; i < data_bytes; ++i) {
+    EXPECT_EQ(data[i], buffer[i]);
+  }
+}
+
+TEST_F(FileUtilProxyTest, Touch) {
+  Time last_accessed_time = Time::Now() - TimeDelta::FromDays(12345);
+  Time last_modified_time = Time::Now() - TimeDelta::FromHours(98765);
+
+  FileUtilProxy::Touch(
+      file_task_runner(),
+      GetTestPlatformFile(PLATFORM_FILE_CREATE |
+                          PLATFORM_FILE_WRITE |
+                          PLATFORM_FILE_WRITE_ATTRIBUTES),
+      last_accessed_time,
+      last_modified_time,
+      Bind(&FileUtilProxyTest::DidFinish, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+  EXPECT_EQ(PLATFORM_FILE_OK, error_);
+
+  PlatformFileInfo info;
+  file_util::GetFileInfo(test_path(), &info);
+
+  // The returned values may only have the seconds precision, so we cast
+  // the double values to int here.
+  EXPECT_EQ(static_cast<int>(last_modified_time.ToDoubleT()),
+            static_cast<int>(info.last_modified.ToDoubleT()));
+  EXPECT_EQ(static_cast<int>(last_accessed_time.ToDoubleT()),
+            static_cast<int>(info.last_accessed.ToDoubleT()));
+}
+
+TEST_F(FileUtilProxyTest, Truncate_Shrink) {
+  // Setup.
+  const char kTestData[] = "0123456789";
+  ASSERT_EQ(10, file_util::WriteFile(test_path(), kTestData, 10));
+  PlatformFileInfo info;
+  file_util::GetFileInfo(test_path(), &info);
+  ASSERT_EQ(10, info.size);
+
+  // Run.
+  FileUtilProxy::Truncate(
+      file_task_runner(),
+      GetTestPlatformFile(PLATFORM_FILE_OPEN | PLATFORM_FILE_WRITE),
+      7,
+      Bind(&FileUtilProxyTest::DidFinish, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+
+  // Verify.
+  file_util::GetFileInfo(test_path(), &info);
+  ASSERT_EQ(7, info.size);
+
+  char buffer[7];
+  EXPECT_EQ(7, file_util::ReadFile(test_path(), buffer, 7));
+  int i = 0;
+  for (; i < 7; ++i)
+    EXPECT_EQ(kTestData[i], buffer[i]);
+}
+
+TEST_F(FileUtilProxyTest, Truncate_Expand) {
+  // Setup.
+  const char kTestData[] = "9876543210";
+  ASSERT_EQ(10, file_util::WriteFile(test_path(), kTestData, 10));
+  PlatformFileInfo info;
+  file_util::GetFileInfo(test_path(), &info);
+  ASSERT_EQ(10, info.size);
+
+  // Run.
+  FileUtilProxy::Truncate(
+      file_task_runner(),
+      GetTestPlatformFile(PLATFORM_FILE_OPEN | PLATFORM_FILE_WRITE),
+      53,
+      Bind(&FileUtilProxyTest::DidFinish, weak_factory_.GetWeakPtr()));
+  MessageLoop::current()->Run();
+
+  // Verify.
+  file_util::GetFileInfo(test_path(), &info);
+  ASSERT_EQ(53, info.size);
+
+  char buffer[53];
+  EXPECT_EQ(53, file_util::ReadFile(test_path(), buffer, 53));
+  int i = 0;
+  for (; i < 10; ++i)
+    EXPECT_EQ(kTestData[i], buffer[i]);
+  for (; i < 53; ++i)
+    EXPECT_EQ(0, buffer[i]);
+}
+
+}  // namespace base