Isolated FS for media devices.

webkit/fileapi/media_file_util.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 "webkit/fileapi/media_file_util.h"
+
+#include "base/memory/scoped_ptr.h"
+#include "webkit/blob/shareable_file_reference.h"
+#include "webkit/fileapi/file_system_operation_context.h"
+#include "webkit/fileapi/file_system_url.h"
+#include "webkit/fileapi/media_device_map_service.h"
+#include "webkit/fileapi/isolated_context.h"
+
+#if defined(OS_WIN)
+#include "webkit/fileapi/mtp_device_interface_win.h"
+#elif defined(OS_POSIX) && !defined(OS_MACOSX)
+#include "webkit/fileapi/mtp_device_interface_linux.h"

[kinuko, 2012/07/25 23:22:28]

I think more common pattern is to have a common interface in a common header
(e.g. webkit/fileapi/mt_device_interface.h) and have platform-specific
implementation inside it as pimpl  (Like how net/base/file_stream.h does).  Then
the consumer of the device interface should only know about the common
interface. 

[kmadhusu, 2012/07/27 02:13:40]

Done. Created media_device_interface.h, media_device_interface_impl.h,
media_device_interface_impl_linux.h && .cc

+#endif
+
+using base::PlatformFileError;
+using base::PlatformFileInfo;
+
+namespace fileapi {
+
+namespace {
+
+bool GetPlatformPathAndDeviceForUrl(
+    const FileSystemURL& url,
+    FilePath* platform_path,
+    scoped_refptr<MediaDeviceInterfaceImpl>* device) {
+  DCHECK(platform_path);
+  std::string filesystem_id;
+  IsolatedContext::FileInfo root;
+  if (!IsolatedContext::GetInstance()->CrackIsolatedPath(
+          url.path(), &filesystem_id, &root, platform_path))

[kinuko, 2012/07/25 23:22:28]

As we chatted offline can we call
IsolatedContext::GetInstance()->GetRegisteredPath(url.filesystem_id(),
&root_path) to get the root path?

[kmadhusu, 2012/07/27 02:13:40]

Done.

+    return false;
+  if (!MediaDeviceMapService::GetInstance()->GetMediaDevice(root.path.value(),
+                                                            device)) {
+    return false;
+  }
+  return true;
+}
+
+}  // namespace
+
+
+MediaFileUtil::MediaFileUtil() {
+}
+
+PlatformFileError MediaFileUtil::CreateOrOpen(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url, int file_flags,
+    PlatformFile* file_handle, bool* created) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+PlatformFileError MediaFileUtil::Close(
+    FileSystemOperationContext* context,
+    PlatformFile file_handle) {
+  // We don't allow open thus Close won't be called.
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+PlatformFileError MediaFileUtil::EnsureFileExists(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url,
+    bool* created) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+PlatformFileError MediaFileUtil::CreateDirectory(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url,
+    bool exclusive,
+    bool recursive) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+PlatformFileError MediaFileUtil::GetFileInfo(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url,
+    PlatformFileInfo* file_info,
+    FilePath* platform_path) {
+  scoped_refptr<MediaDeviceInterfaceImpl> device;
+  if (!GetPlatformPathAndDeviceForUrl(url, platform_path, &device))

[kinuko, 2012/07/25 23:22:28]

after r148440 url.path() will be the platform path

[kmadhusu, 2012/07/27 02:13:40]

Done.

+    return base::PLATFORM_FILE_ERROR_INVALID_URL;
+  return device->GetFileInfo(*platform_path, file_info);
+}
+
+FileSystemFileUtil::AbstractFileEnumerator*
+MediaFileUtil::CreateFileEnumerator(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url,
+    bool recursive) {
+  FilePath platform_path;
+  scoped_refptr<MediaDeviceInterfaceImpl> device;
+  if (!GetPlatformPathAndDeviceForUrl(url, &platform_path, &device))
+    return new FileSystemFileUtil::EmptyFileEnumerator();
+  return device->CreateFileEnumerator(platform_path, recursive);
+}
+
+PlatformFileError MediaFileUtil::GetLocalFilePath(
+    FileSystemOperationContext* context,
+    const FileSystemURL& file_system_url,
+    FilePath* local_file_path) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+PlatformFileError MediaFileUtil::Touch(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url,
+    const base::Time& last_access_time,
+    const base::Time& last_modified_time) {
+  FilePath platform_path;
+  scoped_refptr<MediaDeviceInterfaceImpl> device;
+  if (!GetPlatformPathAndDeviceForUrl(url, &platform_path, &device))
+    return base::PLATFORM_FILE_ERROR_INVALID_URL;
+  return device->Touch(platform_path, last_access_time, last_modified_time);
+}
+
+PlatformFileError MediaFileUtil::Truncate(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url,
+    int64 length) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+bool MediaFileUtil::PathExists(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url) {
+  FilePath platform_path;
+  scoped_refptr<MediaDeviceInterfaceImpl> device;
+  if (!GetPlatformPathAndDeviceForUrl(url, &platform_path, &device))
+    return false;
+  return device->PathExists(platform_path);
+}
+
+bool MediaFileUtil::DirectoryExists(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url) {
+  FilePath platform_path;
+  scoped_refptr<MediaDeviceInterfaceImpl> device;
+  if (!GetPlatformPathAndDeviceForUrl(url, &platform_path, &device))
+    return false;
+  return device->DirectoryExists(platform_path);
+}
+
+bool MediaFileUtil::IsDirectoryEmpty(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url) {
+  FilePath platform_path;
+  scoped_refptr<MediaDeviceInterfaceImpl> device;
+  if (!GetPlatformPathAndDeviceForUrl(url, &platform_path, &device))
+    return false;

[kinuko, 2012/07/25 23:22:28]

Maybe this should rather return true?

[kmadhusu, 2012/07/27 02:13:40]

Done.

+  return device->IsDirectoryEmpty(platform_path);
+}
+
+PlatformFileError MediaFileUtil::CopyOrMoveFile(
+    FileSystemOperationContext* context,
+    const FileSystemURL& src_url,
+    const FileSystemURL& dest_url,
+    bool copy) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+PlatformFileError MediaFileUtil::CopyInForeignFile(
+    FileSystemOperationContext* context,
+    const FilePath& src_file_path,
+    const FileSystemURL& dest_url) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+PlatformFileError MediaFileUtil::DeleteFile(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+PlatformFileError MediaFileUtil::DeleteSingleDirectory(
+    FileSystemOperationContext* context,
+    const FileSystemURL& url) {
+  return base::PLATFORM_FILE_ERROR_SECURITY;
+}
+
+scoped_refptr<webkit_blob::ShareableFileReference>
+    MediaFileUtil::CreateSnapshotFile(
+        FileSystemOperationContext* context,
+        const FileSystemURL& url,
+        base::PlatformFileError* result,
+        base::PlatformFileInfo* file_info,
+        FilePath* platform_path) {
+  return NULL;
+}
+
+}  // namespace fileapi