Port base/files/file_util_proxy to Native Client.

base/files/file_util_proxy.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 "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/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);
 }
 
+#if !defined(OS_NACL)
 // 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) {}
@@ skipping 58 matching lines @@
     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);
 };
+#endif  // !defined(OS_NACL)
 
 class GetFileInfoHelper {
  public:
   GetFileInfoHelper()
       : error_(PLATFORM_FILE_OK) {}
 
+#if !defined(OS_NACL)
   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;
   }
+#endif  // !defined(OS_NACL)
 
   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) {
+#if !defined(OS_NACL)
     bytes_read_ = ReadPlatformFile(file, offset, buffer_.get(), bytes_to_read_);
+#else
+    // TODO(bbudge) Eliminate this when NaCl supports pread.
+    SeekPlatformFile(file, PLATFORM_FILE_FROM_BEGIN, offset);

[brettw, 2013/07/09 20:05:37]

Does it make more sense to implement ReadPlatformFile on NaCl in terms of these
two functions?

[bbudge, 2013/07/09 21:54:54]

Yeah, it looks like it does. Done.

+    bytes_read_ = ReadPlatformFileAtCurrentPos(file, buffer_.get(),
+                                               bytes_to_read_);
+#endif
   }
 
   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) {
+#if !defined(OS_NACL)
     bytes_written_ = WritePlatformFile(file, offset, buffer_.get(),
                                        bytes_to_write_);
+#else
+    // TODO(bbudge) Eliminate this when NaCl supports pwrite.
+    SeekPlatformFile(file, PLATFORM_FILE_FROM_BEGIN, offset);
+    bytes_written_ = WritePlatformFileAtCurrentPos(file, buffer_.get(),
+                                                   bytes_to_write_);
+#endif
   }
 
   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);
 };
 
-
+#if !defined(OS_NACL)
 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;
 }
 
+#endif  // !defined(OS_NACL)
 PlatformFileError CloseAdapter(PlatformFile file_handle) {
   if (!ClosePlatformFile(file_handle)) {
     return PLATFORM_FILE_ERROR_FAILED;
   }
   return PLATFORM_FILE_OK;
 }
 
+#if !defined(OS_NACL)
 PlatformFileError DeleteAdapter(const FilePath& file_path, bool recursive) {
   if (!file_util::PathExists(file_path)) {
     return PLATFORM_FILE_ERROR_NOT_FOUND;
   }
   if (!base::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;
 }
+#endif  // !defined(OS_NACL)
 
 }  // namespace
 
+#if !defined(OS_NACL)
 // 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));
 }
+#endif  // !defined(OS_NACL)
 
 // static
 bool FileUtilProxy::Close(
     TaskRunner* task_runner,
     base::PlatformFile file_handle,
     const StatusCallback& callback) {
   return RelayClose(
       task_runner,
       base::Bind(&CloseAdapter),
       file_handle, callback);
 }
 
+#if !defined(OS_NACL)
 // 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));
 }
+#endif  // !defined(OS_NACL)
 
 // 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));
 }
 
+#if !defined(OS_NACL)
 // 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);
 }
+#endif  // !defined(OS_NACL)
 
 // 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;
@@ skipping 16 matching lines @@
   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));
 }
 
+#if !defined(OS_NACL)
 // 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,
@@ skipping 48 matching lines @@
     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));
 }
+#endif  // !defined(OS_NACL)
 
 // 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