root/chrome/browser/extensions/api/file_system/file_system_api.cc

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DEFINITIONS

This source file includes following definitions.
  1. GetDisplayBaseName
  2. PrettifyPath
  3. PrettifyPath
  4. GetFileTypesFromAcceptOption
  5. GetLastChooseEntryDirectory
  6. SetLastChooseEntryDirectory
  7. GetGrayListedDirectories
  8. RunImpl
  9. response_
  10. CheckWritableFiles
  11. RegisterFileSystemsAndSendResponse
  12. CreateResponse
  13. AddEntryToResponse
  14. HandleWritableFileError
  15. RunImpl
  16. CheckPermissionAndSendResponse
  17. SetIsDirectoryOnFileThread
  18. RunImpl
  19. FilePicker
  20. FilePicker
  21. FileSelected
  22. FileSelectedWithExtraInfo
  23. MultiFilesSelected
  24. MultiFilesSelectedWithExtraInfo
  25. FileSelectionCanceled
  26. ShowPicker
  27. SkipPickerAndAlwaysSelectPathForTest
  28. SkipPickerAndAlwaysSelectPathsForTest
  29. SkipPickerAndSelectSuggestedPathForTest
  30. SkipPickerAndAlwaysCancelForTest
  31. StopSkippingPickerForTest
  32. SkipDirectoryConfirmationForTest
  33. AutoCancelDirectoryConfirmationForTest
  34. StopSkippingDirectoryConfirmationForTest
  35. RegisterTempExternalFileSystemForTest
  36. SetInitialPathOnFileThread
  37. FilesSelected
  38. FileSelectionCanceled
  39. ConfirmDirectoryAccessOnFileThread
  40. OnDirectoryAccessConfirmed
  41. BuildFileTypeInfo
  42. BuildSuggestion
  43. RunImpl
  44. RunImpl
  45. RetainFileEntry
  46. SetIsDirectoryOnFileThread
  47. RunImpl
  48. RunImpl

// 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 "chrome/browser/extensions/api/file_system/file_system_api.h"

#include "apps/app_window.h"
#include "apps/app_window_registry.h"
#include "apps/browser/file_handler_util.h"
#include "apps/saved_files_service.h"
#include "base/bind.h"
#include "base/file_util.h"
#include "base/files/file_path.h"
#include "base/logging.h"
#include "base/path_service.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/sys_string_conversions.h"
#include "base/strings/utf_string_conversions.h"
#include "base/value_conversions.h"
#include "base/values.h"
#include "chrome/browser/extensions/api/file_handlers/app_file_handler_util.h"
#include "chrome/browser/extensions/extension_service.h"
#include "chrome/browser/platform_util.h"
#include "chrome/browser/profiles/profile.h"
#include "chrome/browser/ui/apps/directory_access_confirmation_dialog.h"
#include "chrome/browser/ui/chrome_select_file_policy.h"
#include "chrome/common/chrome_paths.h"
#include "chrome/common/extensions/api/file_system.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/child_process_security_policy.h"
#include "content/public/browser/render_process_host.h"
#include "content/public/browser/render_view_host.h"
#include "content/public/browser/web_contents.h"
#include "content/public/browser/web_contents_view.h"
#include "extensions/browser/extension_system.h"
#include "extensions/common/permissions/api_permission.h"
#include "grit/generated_resources.h"
#include "net/base/mime_util.h"
#include "ui/base/l10n/l10n_util.h"
#include "ui/shell_dialogs/select_file_dialog.h"
#include "ui/shell_dialogs/selected_file_info.h"
#include "webkit/browser/fileapi/external_mount_points.h"
#include "webkit/browser/fileapi/isolated_context.h"
#include "webkit/common/fileapi/file_system_types.h"
#include "webkit/common/fileapi/file_system_util.h"

#if defined(OS_MACOSX)
#include <CoreFoundation/CoreFoundation.h>
#include "base/mac/foundation_util.h"
#endif

#if defined(OS_CHROMEOS)
#include "chrome/browser/chromeos/drive/file_system_util.h"
#endif

using apps::SavedFileEntry;
using apps::SavedFilesService;
using apps::AppWindow;
using fileapi::IsolatedContext;

const char kInvalidCallingPage[] = "Invalid calling page. This function can't "
    "be called from a background page.";
const char kUserCancelled[] = "User cancelled";
const char kWritableFileErrorFormat[] = "Error opening %s";
const char kRequiresFileSystemWriteError[] =
    "Operation requires fileSystem.write permission";
const char kRequiresFileSystemDirectoryError[] =
    "Operation requires fileSystem.directory permission";
const char kMultipleUnsupportedError[] =
    "acceptsMultiple: true is not supported for 'saveFile'";
const char kUnknownIdError[] = "Unknown id";

namespace file_system = extensions::api::file_system;
namespace ChooseEntry = file_system::ChooseEntry;

namespace {

#if defined(OS_MACOSX)
// Retrieves the localized display name for the base name of the given path.
// If the path is not localized, this will just return the base name.
std::string GetDisplayBaseName(const base::FilePath& path) {
  base::ScopedCFTypeRef<CFURLRef> url(CFURLCreateFromFileSystemRepresentation(
      NULL, (const UInt8*)path.value().c_str(), path.value().length(), true));
  if (!url)
    return path.BaseName().value();

  CFStringRef str;
  if (LSCopyDisplayNameForURL(url, &str) != noErr)
    return path.BaseName().value();

  std::string result(base::SysCFStringRefToUTF8(str));
  CFRelease(str);
  return result;
}

// Prettifies |source_path| for OS X, by localizing every component of the
// path. Additionally, if the path is inside the user's home directory, then
// replace the home directory component with "~".
base::FilePath PrettifyPath(const base::FilePath& source_path) {
  base::FilePath home_path;
  PathService::Get(base::DIR_HOME, &home_path);
  DCHECK(source_path.IsAbsolute());

  // Break down the incoming path into components, and grab the display name
  // for every component. This will match app bundles, ".localized" folders,
  // and localized subfolders of the user's home directory.
  // Don't grab the display name of the first component, i.e., "/", as it'll
  // show up as the HDD name.
  std::vector<base::FilePath::StringType> components;
  source_path.GetComponents(&components);
  base::FilePath display_path = base::FilePath(components[0]);
  base::FilePath actual_path = display_path;
  for (std::vector<base::FilePath::StringType>::iterator i =
           components.begin() + 1; i != components.end(); ++i) {
    actual_path = actual_path.Append(*i);
    if (actual_path == home_path) {
      display_path = base::FilePath("~");
      home_path = base::FilePath();
      continue;
    }
    std::string display = GetDisplayBaseName(actual_path);
    display_path = display_path.Append(display);
  }
  DCHECK_EQ(actual_path.value(), source_path.value());
  return display_path;
}
#else  // defined(OS_MACOSX)
// Prettifies |source_path|, by replacing the user's home directory with "~"
// (if applicable).
base::FilePath PrettifyPath(const base::FilePath& source_path) {
  base::FilePath home_path;
  base::FilePath display_path = base::FilePath::FromUTF8Unsafe("~");
  if (PathService::Get(base::DIR_HOME, &home_path)
      && home_path.AppendRelativePath(source_path, &display_path))
    return display_path;
  return source_path;
}
#endif  // defined(OS_MACOSX)

bool g_skip_picker_for_test = false;
bool g_use_suggested_path_for_test = false;
base::FilePath* g_path_to_be_picked_for_test;
std::vector<base::FilePath>* g_paths_to_be_picked_for_test;
bool g_skip_directory_confirmation_for_test = false;
bool g_allow_directory_access_for_test = false;

// Expand the mime-types and extensions provided in an AcceptOption, returning
// them within the passed extension vector. Returns false if no valid types
// were found.
bool GetFileTypesFromAcceptOption(
    const file_system::AcceptOption& accept_option,
    std::vector<base::FilePath::StringType>* extensions,
    base::string16* description) {
  std::set<base::FilePath::StringType> extension_set;
  int description_id = 0;

  if (accept_option.mime_types.get()) {
    std::vector<std::string>* list = accept_option.mime_types.get();
    bool valid_type = false;
    for (std::vector<std::string>::const_iterator iter = list->begin();
         iter != list->end(); ++iter) {
      std::vector<base::FilePath::StringType> inner;
      std::string accept_type = *iter;
      StringToLowerASCII(&accept_type);
      net::GetExtensionsForMimeType(accept_type, &inner);
      if (inner.empty())
        continue;

      if (valid_type)
        description_id = 0;  // We already have an accept type with label; if
                             // we find another, give up and use the default.
      else if (accept_type == "image/*")
        description_id = IDS_IMAGE_FILES;
      else if (accept_type == "audio/*")
        description_id = IDS_AUDIO_FILES;
      else if (accept_type == "video/*")
        description_id = IDS_VIDEO_FILES;

      extension_set.insert(inner.begin(), inner.end());
      valid_type = true;
    }
  }

  if (accept_option.extensions.get()) {
    std::vector<std::string>* list = accept_option.extensions.get();
    for (std::vector<std::string>::const_iterator iter = list->begin();
         iter != list->end(); ++iter) {
      std::string extension = *iter;
      StringToLowerASCII(&extension);
#if defined(OS_WIN)
      extension_set.insert(base::UTF8ToWide(*iter));
#else
      extension_set.insert(*iter);
#endif
    }
  }

  extensions->assign(extension_set.begin(), extension_set.end());
  if (extensions->empty())
    return false;

  if (accept_option.description.get())
    *description = base::UTF8ToUTF16(*accept_option.description.get());
  else if (description_id)
    *description = l10n_util::GetStringUTF16(description_id);

  return true;
}

// Key for the path of the directory of the file last chosen by the user in
// response to a chrome.fileSystem.chooseEntry() call.
const char kLastChooseEntryDirectory[] = "last_choose_file_directory";

const int kGraylistedPaths[] = {
  base::DIR_HOME,
#if defined(OS_WIN)
  base::DIR_PROGRAM_FILES,
  base::DIR_PROGRAM_FILESX86,
  base::DIR_WINDOWS,
#endif
};

}  // namespace

namespace extensions {

namespace file_system_api {

base::FilePath GetLastChooseEntryDirectory(const ExtensionPrefs* prefs,
                                           const std::string& extension_id) {
  base::FilePath path;
  std::string string_path;
  if (prefs->ReadPrefAsString(extension_id,
                              kLastChooseEntryDirectory,
                              &string_path)) {
    path = base::FilePath::FromUTF8Unsafe(string_path);
  }
  return path;
}

void SetLastChooseEntryDirectory(ExtensionPrefs* prefs,
                                 const std::string& extension_id,
                                 const base::FilePath& path) {
  prefs->UpdateExtensionPref(extension_id,
                             kLastChooseEntryDirectory,
                             base::CreateFilePathValue(path));
}

std::vector<base::FilePath> GetGrayListedDirectories() {
  std::vector<base::FilePath> graylisted_directories;
  for (size_t i = 0; i < arraysize(kGraylistedPaths); ++i) {
    base::FilePath graylisted_path;
    if (PathService::Get(kGraylistedPaths[i], &graylisted_path))
      graylisted_directories.push_back(graylisted_path);
  }
  return graylisted_directories;
}

}  // namespace file_system_api

bool FileSystemGetDisplayPathFunction::RunImpl() {
  std::string filesystem_name;
  std::string filesystem_path;
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &filesystem_name));
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_path));

  base::FilePath file_path;
  if (!app_file_handler_util::ValidateFileEntryAndGetPath(filesystem_name,
                                                          filesystem_path,
                                                          render_view_host_,
                                                          &file_path,
                                                          &error_))
    return false;

  file_path = PrettifyPath(file_path);
  SetResult(new base::StringValue(file_path.value()));
  return true;
}

FileSystemEntryFunction::FileSystemEntryFunction()
    : multiple_(false),
      is_directory_(false),
      response_(NULL) {}

void FileSystemEntryFunction::CheckWritableFiles(
    const std::vector<base::FilePath>& paths) {
  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
  app_file_handler_util::CheckWritableFiles(
      paths,
      GetProfile(),
      is_directory_,
      base::Bind(&FileSystemEntryFunction::RegisterFileSystemsAndSendResponse,
                 this,
                 paths),
      base::Bind(&FileSystemEntryFunction::HandleWritableFileError, this));
}

void FileSystemEntryFunction::RegisterFileSystemsAndSendResponse(
    const std::vector<base::FilePath>& paths) {
  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
  if (!render_view_host_)
    return;

  CreateResponse();
  for (std::vector<base::FilePath>::const_iterator it = paths.begin();
       it != paths.end(); ++it) {
    AddEntryToResponse(*it, "");
  }
  SendResponse(true);
}

void FileSystemEntryFunction::CreateResponse() {
  DCHECK(!response_);
  response_ = new base::DictionaryValue();
  base::ListValue* list = new base::ListValue();
  response_->Set("entries", list);
  response_->SetBoolean("multiple", multiple_);
  SetResult(response_);
}

void FileSystemEntryFunction::AddEntryToResponse(
    const base::FilePath& path,
    const std::string& id_override) {
  DCHECK(response_);
  apps::file_handler_util::GrantedFileEntry file_entry =
      extensions::app_file_handler_util::CreateFileEntry(
          GetProfile(),
          GetExtension(),
          render_view_host_->GetProcess()->GetID(),
          path,
          is_directory_);
  base::ListValue* entries;
  bool success = response_->GetList("entries", &entries);
  DCHECK(success);

  base::DictionaryValue* entry = new base::DictionaryValue();
  entry->SetString("fileSystemId", file_entry.filesystem_id);
  entry->SetString("baseName", file_entry.registered_name);
  if (id_override.empty())
    entry->SetString("id", file_entry.id);
  else
    entry->SetString("id", id_override);
  entry->SetBoolean("isDirectory", is_directory_);
  entries->Append(entry);
}

void FileSystemEntryFunction::HandleWritableFileError(
    const base::FilePath& error_path) {
  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
  error_ = base::StringPrintf(kWritableFileErrorFormat,
                              error_path.BaseName().AsUTF8Unsafe().c_str());
  SendResponse(false);
}

bool FileSystemGetWritableEntryFunction::RunImpl() {
  std::string filesystem_name;
  std::string filesystem_path;
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &filesystem_name));
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_path));

  if (!app_file_handler_util::HasFileSystemWritePermission(extension_)) {
    error_ = kRequiresFileSystemWriteError;
    return false;
  }

  if (!app_file_handler_util::ValidateFileEntryAndGetPath(filesystem_name,
                                                          filesystem_path,
                                                          render_view_host_,
                                                          &path_,
                                                          &error_))
    return false;

  content::BrowserThread::PostTaskAndReply(
      content::BrowserThread::FILE,
      FROM_HERE,
      base::Bind(
          &FileSystemGetWritableEntryFunction::SetIsDirectoryOnFileThread,
          this),
      base::Bind(
          &FileSystemGetWritableEntryFunction::CheckPermissionAndSendResponse,
          this));
  return true;
}

void FileSystemGetWritableEntryFunction::CheckPermissionAndSendResponse() {
  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
  if (is_directory_ &&
      !extension_->HasAPIPermission(APIPermission::kFileSystemDirectory)) {
    error_ = kRequiresFileSystemDirectoryError;
    SendResponse(false);
  }
  std::vector<base::FilePath> paths;
  paths.push_back(path_);
  CheckWritableFiles(paths);
}

void FileSystemGetWritableEntryFunction::SetIsDirectoryOnFileThread() {
  DCHECK_CURRENTLY_ON(content::BrowserThread::FILE);
  if (base::DirectoryExists(path_)) {
    is_directory_ = true;
  }
}

bool FileSystemIsWritableEntryFunction::RunImpl() {
  std::string filesystem_name;
  std::string filesystem_path;
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &filesystem_name));
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_path));

  std::string filesystem_id;
  if (!fileapi::CrackIsolatedFileSystemName(filesystem_name, &filesystem_id)) {
    error_ = app_file_handler_util::kInvalidParameters;
    return false;
  }

  content::ChildProcessSecurityPolicy* policy =
      content::ChildProcessSecurityPolicy::GetInstance();
  int renderer_id = render_view_host_->GetProcess()->GetID();
  bool is_writable = policy->CanReadWriteFileSystem(renderer_id,
                                                    filesystem_id);

  SetResult(new base::FundamentalValue(is_writable));
  return true;
}

// Handles showing a dialog to the user to ask for the filename for a file to
// save or open.
class FileSystemChooseEntryFunction::FilePicker
    : public ui::SelectFileDialog::Listener {
 public:
  FilePicker(FileSystemChooseEntryFunction* function,
             content::WebContents* web_contents,
             const base::FilePath& suggested_name,
             const ui::SelectFileDialog::FileTypeInfo& file_type_info,
             ui::SelectFileDialog::Type picker_type)
      : function_(function) {
    select_file_dialog_ = ui::SelectFileDialog::Create(
        this, new ChromeSelectFilePolicy(web_contents));
    gfx::NativeWindow owning_window = web_contents ?
        platform_util::GetTopLevel(web_contents->GetView()->GetNativeView()) :
        NULL;

    if (g_skip_picker_for_test) {
      if (g_use_suggested_path_for_test) {
        content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE,
            base::Bind(
                &FileSystemChooseEntryFunction::FilePicker::FileSelected,
                base::Unretained(this), suggested_name, 1,
                static_cast<void*>(NULL)));
      } else if (g_path_to_be_picked_for_test) {
        content::BrowserThread::PostTask(
            content::BrowserThread::UI, FROM_HERE,
            base::Bind(
                &FileSystemChooseEntryFunction::FilePicker::FileSelected,
                base::Unretained(this), *g_path_to_be_picked_for_test, 1,
                static_cast<void*>(NULL)));
      } else if (g_paths_to_be_picked_for_test) {
        content::BrowserThread::PostTask(
            content::BrowserThread::UI,
            FROM_HERE,
            base::Bind(
                &FileSystemChooseEntryFunction::FilePicker::MultiFilesSelected,
                base::Unretained(this),
                *g_paths_to_be_picked_for_test,
                static_cast<void*>(NULL)));
      } else {
        content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE,
            base::Bind(
                &FileSystemChooseEntryFunction::FilePicker::
                    FileSelectionCanceled,
                base::Unretained(this), static_cast<void*>(NULL)));
      }
      return;
    }

    select_file_dialog_->SelectFile(picker_type,
                                    base::string16(),
                                    suggested_name,
                                    &file_type_info,
                                    0,
                                    base::FilePath::StringType(),
                                    owning_window,
                                    NULL);
  }

  virtual ~FilePicker() {}

 private:
  // ui::SelectFileDialog::Listener implementation.
  virtual void FileSelected(const base::FilePath& path,
                            int index,
                            void* params) OVERRIDE {
    std::vector<base::FilePath> paths;
    paths.push_back(path);
    MultiFilesSelected(paths, params);
  }

  virtual void FileSelectedWithExtraInfo(const ui::SelectedFileInfo& file,
                                         int index,
                                         void* params) OVERRIDE {
    // Normally, file.local_path is used because it is a native path to the
    // local read-only cached file in the case of remote file system like
    // Chrome OS's Google Drive integration. Here, however, |file.file_path| is
    // necessary because we need to create a FileEntry denoting the remote file,
    // not its cache. On other platforms than Chrome OS, they are the same.
    //
    // TODO(kinaba): remove this, once after the file picker implements proper
    // switch of the path treatment depending on the |support_drive| flag.
    FileSelected(file.file_path, index, params);
  }

  virtual void MultiFilesSelected(const std::vector<base::FilePath>& files,
                                  void* params) OVERRIDE {
    function_->FilesSelected(files);
    delete this;
  }

  virtual void MultiFilesSelectedWithExtraInfo(
      const std::vector<ui::SelectedFileInfo>& files,
      void* params) OVERRIDE {
    std::vector<base::FilePath> paths;
    for (std::vector<ui::SelectedFileInfo>::const_iterator it = files.begin();
         it != files.end(); ++it) {
      paths.push_back(it->file_path);
    }
    MultiFilesSelected(paths, params);
  }

  virtual void FileSelectionCanceled(void* params) OVERRIDE {
    function_->FileSelectionCanceled();
    delete this;
  }

  scoped_refptr<ui::SelectFileDialog> select_file_dialog_;
  scoped_refptr<FileSystemChooseEntryFunction> function_;

  DISALLOW_COPY_AND_ASSIGN(FilePicker);
};

void FileSystemChooseEntryFunction::ShowPicker(
    const ui::SelectFileDialog::FileTypeInfo& file_type_info,
    ui::SelectFileDialog::Type picker_type) {
  // TODO(asargent/benwells) - As a short term remediation for crbug.com/179010
  // we're adding the ability for a whitelisted extension to use this API since
  // chrome.fileBrowserHandler.selectFile is ChromeOS-only. Eventually we'd
  // like a better solution and likely this code will go back to being
  // platform-app only.
  content::WebContents* web_contents = NULL;
  if (extension_->is_platform_app()) {
    apps::AppWindowRegistry* registry =
        apps::AppWindowRegistry::Get(GetProfile());
    DCHECK(registry);
    AppWindow* app_window =
        registry->GetAppWindowForRenderViewHost(render_view_host());
    if (!app_window) {
      error_ = kInvalidCallingPage;
      SendResponse(false);
      return;
    }
    web_contents = app_window->web_contents();
  } else {
    web_contents = GetAssociatedWebContents();
  }
  // The file picker will hold a reference to this function instance, preventing
  // its destruction (and subsequent sending of the function response) until the
  // user has selected a file or cancelled the picker. At that point, the picker
  // will delete itself, which will also free the function instance.
  new FilePicker(
      this, web_contents, initial_path_, file_type_info, picker_type);
}

// static
void FileSystemChooseEntryFunction::SkipPickerAndAlwaysSelectPathForTest(
    base::FilePath* path) {
  g_skip_picker_for_test = true;
  g_use_suggested_path_for_test = false;
  g_path_to_be_picked_for_test = path;
  g_paths_to_be_picked_for_test = NULL;
}

void FileSystemChooseEntryFunction::SkipPickerAndAlwaysSelectPathsForTest(
    std::vector<base::FilePath>* paths) {
  g_skip_picker_for_test = true;
  g_use_suggested_path_for_test = false;
  g_paths_to_be_picked_for_test = paths;
}

// static
void FileSystemChooseEntryFunction::SkipPickerAndSelectSuggestedPathForTest() {
  g_skip_picker_for_test = true;
  g_use_suggested_path_for_test = true;
  g_path_to_be_picked_for_test = NULL;
  g_paths_to_be_picked_for_test = NULL;
}

// static
void FileSystemChooseEntryFunction::SkipPickerAndAlwaysCancelForTest() {
  g_skip_picker_for_test = true;
  g_use_suggested_path_for_test = false;
  g_path_to_be_picked_for_test = NULL;
  g_paths_to_be_picked_for_test = NULL;
}

// static
void FileSystemChooseEntryFunction::StopSkippingPickerForTest() {
  g_skip_picker_for_test = false;
}

// static
void FileSystemChooseEntryFunction::SkipDirectoryConfirmationForTest() {
  g_skip_directory_confirmation_for_test = true;
  g_allow_directory_access_for_test = true;
}

// static
void FileSystemChooseEntryFunction::AutoCancelDirectoryConfirmationForTest() {
  g_skip_directory_confirmation_for_test = true;
  g_allow_directory_access_for_test = false;
}

// static
void FileSystemChooseEntryFunction::StopSkippingDirectoryConfirmationForTest() {
  g_skip_directory_confirmation_for_test = false;
}

// static
void FileSystemChooseEntryFunction::RegisterTempExternalFileSystemForTest(
    const std::string& name, const base::FilePath& path) {
  // For testing on Chrome OS, where to deal with remote and local paths
  // smoothly, all accessed paths need to be registered in the list of
  // external mount points.
  fileapi::ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
      name,
      fileapi::kFileSystemTypeNativeLocal,
      fileapi::FileSystemMountOption(),
      path);
}

void FileSystemChooseEntryFunction::SetInitialPathOnFileThread(
    const base::FilePath& suggested_name,
    const base::FilePath& previous_path) {
  DCHECK_CURRENTLY_ON(content::BrowserThread::FILE);
  if (!previous_path.empty() && base::DirectoryExists(previous_path)) {
    initial_path_ = previous_path.Append(suggested_name);
  } else {
    base::FilePath documents_dir;
    if (PathService::Get(chrome::DIR_USER_DOCUMENTS, &documents_dir)) {
      initial_path_ = documents_dir.Append(suggested_name);
    } else {
      initial_path_ = suggested_name;
    }
  }
}

void FileSystemChooseEntryFunction::FilesSelected(
    const std::vector<base::FilePath>& paths) {
  DCHECK(!paths.empty());
  base::FilePath last_choose_directory;
  if (is_directory_) {
    last_choose_directory = paths[0];
  } else {
    last_choose_directory = paths[0].DirName();
  }
  file_system_api::SetLastChooseEntryDirectory(
      ExtensionPrefs::Get(GetProfile()),
      GetExtension()->id(),
      last_choose_directory);
  if (is_directory_) {
    // Get the WebContents for the app window to be the parent window of the
    // confirmation dialog if necessary.
    apps::AppWindowRegistry* registry =
        apps::AppWindowRegistry::Get(GetProfile());
    DCHECK(registry);
    AppWindow* app_window =
        registry->GetAppWindowForRenderViewHost(render_view_host());
    if (!app_window) {
      error_ = kInvalidCallingPage;
      SendResponse(false);
      return;
    }
    content::WebContents* web_contents = app_window->web_contents();

    content::BrowserThread::PostTask(
        content::BrowserThread::FILE,
        FROM_HERE,
        base::Bind(
            &FileSystemChooseEntryFunction::ConfirmDirectoryAccessOnFileThread,
            this,
            paths,
            web_contents));
    return;
  }

  OnDirectoryAccessConfirmed(paths);
}

void FileSystemChooseEntryFunction::FileSelectionCanceled() {
  error_ = kUserCancelled;
  SendResponse(false);
}

void FileSystemChooseEntryFunction::ConfirmDirectoryAccessOnFileThread(
    const std::vector<base::FilePath>& paths,
    content::WebContents* web_contents) {
  DCHECK_EQ(paths.size(), 1u);
#if defined(OS_CHROMEOS)
  const base::FilePath path =
      drive::util::IsUnderDriveMountPoint(paths[0]) ? paths[0] :
          base::MakeAbsoluteFilePath(paths[0]);
#else
  const base::FilePath path = base::MakeAbsoluteFilePath(paths[0]);
#endif
  if (path.empty()) {
    content::BrowserThread::PostTask(
        content::BrowserThread::UI,
        FROM_HERE,
        base::Bind(&FileSystemChooseEntryFunction::FileSelectionCanceled,
                   this));
    return;
  }

  for (size_t i = 0; i < arraysize(kGraylistedPaths); i++) {
    base::FilePath graylisted_path;
    if (PathService::Get(kGraylistedPaths[i], &graylisted_path) &&
        (path == graylisted_path || path.IsParent(graylisted_path))) {
      if (g_skip_directory_confirmation_for_test) {
        if (g_allow_directory_access_for_test) {
          break;
        } else {
          content::BrowserThread::PostTask(
              content::BrowserThread::UI,
              FROM_HERE,
              base::Bind(&FileSystemChooseEntryFunction::FileSelectionCanceled,
                         this));
        }
        return;
      }

      content::BrowserThread::PostTask(
          content::BrowserThread::UI,
          FROM_HERE,
          base::Bind(
              CreateDirectoryAccessConfirmationDialog,
              app_file_handler_util::HasFileSystemWritePermission(extension_),
              base::UTF8ToUTF16(extension_->name()),
              web_contents,
              base::Bind(
                  &FileSystemChooseEntryFunction::OnDirectoryAccessConfirmed,
                  this,
                  paths),
              base::Bind(&FileSystemChooseEntryFunction::FileSelectionCanceled,
                         this)));
      return;
    }
  }

  content::BrowserThread::PostTask(
      content::BrowserThread::UI,
      FROM_HERE,
      base::Bind(&FileSystemChooseEntryFunction::OnDirectoryAccessConfirmed,
                 this, paths));
}

void FileSystemChooseEntryFunction::OnDirectoryAccessConfirmed(
    const std::vector<base::FilePath>& paths) {
  if (app_file_handler_util::HasFileSystemWritePermission(extension_)) {
    CheckWritableFiles(paths);
    return;
  }

  // Don't need to check the file, it's for reading.
  RegisterFileSystemsAndSendResponse(paths);
}

void FileSystemChooseEntryFunction::BuildFileTypeInfo(
    ui::SelectFileDialog::FileTypeInfo* file_type_info,
    const base::FilePath::StringType& suggested_extension,
    const AcceptOptions* accepts,
    const bool* acceptsAllTypes) {
  file_type_info->include_all_files = true;
  if (acceptsAllTypes)
    file_type_info->include_all_files = *acceptsAllTypes;

  bool need_suggestion = !file_type_info->include_all_files &&
                         !suggested_extension.empty();

  if (accepts) {
    typedef file_system::AcceptOption AcceptOption;
    for (std::vector<linked_ptr<AcceptOption> >::const_iterator iter =
            accepts->begin(); iter != accepts->end(); ++iter) {
      base::string16 description;
      std::vector<base::FilePath::StringType> extensions;

      if (!GetFileTypesFromAcceptOption(**iter, &extensions, &description))
        continue;  // No extensions were found.

      file_type_info->extensions.push_back(extensions);
      file_type_info->extension_description_overrides.push_back(description);

      // If we still need to find suggested_extension, hunt for it inside the
      // extensions returned from GetFileTypesFromAcceptOption.
      if (need_suggestion && std::find(extensions.begin(),
              extensions.end(), suggested_extension) != extensions.end()) {
        need_suggestion = false;
      }
    }
  }

  // If there's nothing in our accepted extension list or we couldn't find the
  // suggested extension required, then default to accepting all types.
  if (file_type_info->extensions.empty() || need_suggestion)
    file_type_info->include_all_files = true;
}

void FileSystemChooseEntryFunction::BuildSuggestion(
    const std::string *opt_name,
    base::FilePath* suggested_name,
    base::FilePath::StringType* suggested_extension) {
  if (opt_name) {
    *suggested_name = base::FilePath::FromUTF8Unsafe(*opt_name);

    // Don't allow any path components; shorten to the base name. This should
    // result in a relative path, but in some cases may not. Clear the
    // suggestion for safety if this is the case.
    *suggested_name = suggested_name->BaseName();
    if (suggested_name->IsAbsolute())
      *suggested_name = base::FilePath();

    *suggested_extension = suggested_name->Extension();
    if (!suggested_extension->empty())
      suggested_extension->erase(suggested_extension->begin());  // drop the .
  }
}

bool FileSystemChooseEntryFunction::RunImpl() {
  scoped_ptr<ChooseEntry::Params> params(ChooseEntry::Params::Create(*args_));
  EXTENSION_FUNCTION_VALIDATE(params.get());

  base::FilePath suggested_name;
  ui::SelectFileDialog::FileTypeInfo file_type_info;
  ui::SelectFileDialog::Type picker_type =
      ui::SelectFileDialog::SELECT_OPEN_FILE;

  file_system::ChooseEntryOptions* options = params->options.get();
  if (options) {
    multiple_ = options->accepts_multiple;
    if (multiple_)
      picker_type = ui::SelectFileDialog::SELECT_OPEN_MULTI_FILE;

    if (options->type == file_system::CHOOSE_ENTRY_TYPE_OPENWRITABLEFILE &&
        !app_file_handler_util::HasFileSystemWritePermission(extension_)) {
      error_ = kRequiresFileSystemWriteError;
      return false;
    } else if (options->type == file_system::CHOOSE_ENTRY_TYPE_SAVEFILE) {
      if (!app_file_handler_util::HasFileSystemWritePermission(extension_)) {
        error_ = kRequiresFileSystemWriteError;
        return false;
      }
      if (multiple_) {
        error_ = kMultipleUnsupportedError;
        return false;
      }
      picker_type = ui::SelectFileDialog::SELECT_SAVEAS_FILE;
    } else if (options->type == file_system::CHOOSE_ENTRY_TYPE_OPENDIRECTORY) {
      is_directory_ = true;
      if (!extension_->HasAPIPermission(APIPermission::kFileSystemDirectory)) {
        error_ = kRequiresFileSystemDirectoryError;
        return false;
      }
      if (multiple_) {
        error_ = kMultipleUnsupportedError;
        return false;
      }
      picker_type = ui::SelectFileDialog::SELECT_FOLDER;
    }

    base::FilePath::StringType suggested_extension;
    BuildSuggestion(options->suggested_name.get(), &suggested_name,
        &suggested_extension);

    BuildFileTypeInfo(&file_type_info, suggested_extension,
        options->accepts.get(), options->accepts_all_types.get());
  }

  file_type_info.support_drive = true;

  base::FilePath previous_path = file_system_api::GetLastChooseEntryDirectory(
      ExtensionPrefs::Get(GetProfile()), GetExtension()->id());

  content::BrowserThread::PostTaskAndReply(
      content::BrowserThread::FILE,
      FROM_HERE,
      base::Bind(&FileSystemChooseEntryFunction::SetInitialPathOnFileThread,
                 this,
                 suggested_name,
                 previous_path),
      base::Bind(&FileSystemChooseEntryFunction::ShowPicker,
                 this,
                 file_type_info,
                 picker_type));
  return true;
}

bool FileSystemRetainEntryFunction::RunImpl() {
  std::string entry_id;
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &entry_id));
  SavedFilesService* saved_files_service = SavedFilesService::Get(GetProfile());
  // Add the file to the retain list if it is not already on there.
  if (!saved_files_service->IsRegistered(extension_->id(), entry_id)) {
    std::string filesystem_name;
    std::string filesystem_path;
    EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_name));
    EXTENSION_FUNCTION_VALIDATE(args_->GetString(2, &filesystem_path));
    if (!app_file_handler_util::ValidateFileEntryAndGetPath(filesystem_name,
                                                            filesystem_path,
                                                            render_view_host_,
                                                            &path_,
                                                            &error_)) {
      return false;
    }

    content::BrowserThread::PostTaskAndReply(
        content::BrowserThread::FILE,
        FROM_HERE,
        base::Bind(&FileSystemRetainEntryFunction::SetIsDirectoryOnFileThread,
                   this),
        base::Bind(&FileSystemRetainEntryFunction::RetainFileEntry,
                   this,
                   entry_id));
    return true;
  }

  saved_files_service->EnqueueFileEntry(extension_->id(), entry_id);
  SendResponse(true);
  return true;
}

void FileSystemRetainEntryFunction::RetainFileEntry(
    const std::string& entry_id) {
  SavedFilesService* saved_files_service = SavedFilesService::Get(GetProfile());
  saved_files_service->RegisterFileEntry(
      extension_->id(), entry_id, path_, is_directory_);
  saved_files_service->EnqueueFileEntry(extension_->id(), entry_id);
  SendResponse(true);
}

void FileSystemRetainEntryFunction::SetIsDirectoryOnFileThread() {
  is_directory_ = base::DirectoryExists(path_);
}

bool FileSystemIsRestorableFunction::RunImpl() {
  std::string entry_id;
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &entry_id));
  SetResult(new base::FundamentalValue(SavedFilesService::Get(
      GetProfile())->IsRegistered(extension_->id(), entry_id)));
  return true;
}

bool FileSystemRestoreEntryFunction::RunImpl() {
  std::string entry_id;
  bool needs_new_entry;
  EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &entry_id));
  EXTENSION_FUNCTION_VALIDATE(args_->GetBoolean(1, &needs_new_entry));
  const SavedFileEntry* file_entry = SavedFilesService::Get(
      GetProfile())->GetFileEntry(extension_->id(), entry_id);
  if (!file_entry) {
    error_ = kUnknownIdError;
    return false;
  }

  SavedFilesService::Get(GetProfile())
      ->EnqueueFileEntry(extension_->id(), entry_id);

  // Only create a new file entry if the renderer requests one.
  // |needs_new_entry| will be false if the renderer already has an Entry for
  // |entry_id|.
  if (needs_new_entry) {
    is_directory_ = file_entry->is_directory;
    CreateResponse();
    AddEntryToResponse(file_entry->path, file_entry->id);
  }
  SendResponse(true);
  return true;
}

}  // namespace extensions

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