Media Galleries: Access MTP devices by file ids rather than file paths.

chrome/browser/media_galleries/linux/mtp_device_task_helper.cc

 // Copyright 2013 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/media_galleries/linux/mtp_device_task_helper.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/numerics/safe_conversions.h"
+#include "base/strings/string_number_conversions.h"
 #include "chrome/browser/media_galleries/linux/mtp_device_object_enumerator.h"
 #include "chrome/browser/media_galleries/linux/mtp_read_file_worker.h"
 #include "chrome/browser/media_galleries/linux/snapshot_file_details.h"
 #include "components/storage_monitor/storage_monitor.h"
 #include "content/public/browser/browser_thread.h"
 #include "device/media_transfer_protocol/media_transfer_protocol_manager.h"
 #include "net/base/io_buffer.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 #include "webkit/browser/fileapi/async_file_util.h"
 #include "webkit/common/fileapi/file_system_util.h"
@@ skipping 46 matching lines @@
                                      base::Bind(callback, true));
     return;
   }
   GetMediaTransferProtocolManager()->OpenStorage(
       storage_name, mtpd::kReadOnlyMode,
       base::Bind(&MTPDeviceTaskHelper::OnDidOpenStorage,
                  weak_ptr_factory_.GetWeakPtr(),
                  callback));
 }
 
-void MTPDeviceTaskHelper::GetFileInfoByPath(
-    const std::string& file_path,
+void MTPDeviceTaskHelper::GetFileInfoById(
+    uint32 file_id,
     const GetFileInfoSuccessCallback& success_callback,
     const ErrorCallback& error_callback) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (device_handle_.empty())
     return HandleDeviceError(error_callback, base::File::FILE_ERROR_FAILED);
 
-  GetMediaTransferProtocolManager()->GetFileInfoByPath(
-      device_handle_, file_path,
+  GetMediaTransferProtocolManager()->GetFileInfoById(
+      device_handle_, file_id,
       base::Bind(&MTPDeviceTaskHelper::OnGetFileInfo,
                  weak_ptr_factory_.GetWeakPtr(),
                  success_callback,
                  error_callback));
 }
 
-void MTPDeviceTaskHelper::ReadDirectoryByPath(
-    const std::string& dir_path,
+void MTPDeviceTaskHelper::ReadDirectoryById(
+    uint32 dir_id,
     const ReadDirectorySuccessCallback& success_callback,
     const ErrorCallback& error_callback) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (device_handle_.empty())
     return HandleDeviceError(error_callback, base::File::FILE_ERROR_FAILED);
 
-  GetMediaTransferProtocolManager()->ReadDirectoryByPath(
-      device_handle_, dir_path,
-      base::Bind(&MTPDeviceTaskHelper::OnDidReadDirectoryByPath,
+  GetMediaTransferProtocolManager()->ReadDirectoryById(
+      device_handle_, dir_id,
+      base::Bind(&MTPDeviceTaskHelper::OnDidReadDirectoryById,
                  weak_ptr_factory_.GetWeakPtr(),
                  success_callback,
                  error_callback));
 }
 
 void MTPDeviceTaskHelper::WriteDataIntoSnapshotFile(
     const SnapshotRequestInfo& request_info,
     const base::File::Info& snapshot_file_info) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (device_handle_.empty()) {
     return HandleDeviceError(request_info.error_callback,
                              base::File::FILE_ERROR_FAILED);
   }
 
   if (!read_file_worker_)
     read_file_worker_.reset(new MTPReadFileWorker(device_handle_));
   read_file_worker_->WriteDataIntoSnapshotFile(request_info,
                                                snapshot_file_info);
 }
 
 void MTPDeviceTaskHelper::ReadBytes(
     const MTPDeviceAsyncDelegate::ReadBytesRequest& request) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (device_handle_.empty()) {
     return HandleDeviceError(request.error_callback,
                              base::File::FILE_ERROR_FAILED);
   }
 
-  GetMediaTransferProtocolManager()->GetFileInfoByPath(
-      device_handle_, request.device_file_relative_path,
+  GetMediaTransferProtocolManager()->GetFileInfoById(
+      device_handle_, request.file_id,
       base::Bind(&MTPDeviceTaskHelper::OnGetFileInfoToReadBytes,
                  weak_ptr_factory_.GetWeakPtr(), request));
 }
 
 void MTPDeviceTaskHelper::CloseStorage() const {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (device_handle_.empty())
     return;
   GetMediaTransferProtocolManager()->CloseStorage(device_handle_,
                                                   base::Bind(&DoNothing));
@@ skipping 20 matching lines @@
     return HandleDeviceError(error_callback,
                              base::File::FILE_ERROR_NOT_FOUND);
   }
 
   content::BrowserThread::PostTask(
       content::BrowserThread::IO,
       FROM_HERE,
       base::Bind(success_callback, FileInfoFromMTPFileEntry(file_entry)));
 }
 
-void MTPDeviceTaskHelper::OnDidReadDirectoryByPath(
+void MTPDeviceTaskHelper::OnDidReadDirectoryById(
     const ReadDirectorySuccessCallback& success_callback,
     const ErrorCallback& error_callback,
     const std::vector<MtpFileEntry>& file_entries,
     bool error) const {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (error)
     return HandleDeviceError(error_callback, base::File::FILE_ERROR_FAILED);
 
   fileapi::AsyncFileUtil::EntryList entries;
   base::FilePath current;
   MTPDeviceObjectEnumerator file_enum(file_entries);
   while (!(current = file_enum.Next()).empty()) {
     fileapi::DirectoryEntry entry;
     entry.name = fileapi::VirtualPath::BaseName(current).value();
+    uint32 file_id = 0;
+    bool ret = file_enum.GetEntryId(&file_id);
+    DCHECK(ret);
+    entry.name.push_back(',');
+    entry.name += base::UintToString(file_id);
     entry.is_directory = file_enum.IsDirectory();
     entry.size = file_enum.Size();
     entry.last_modified_time = file_enum.LastModifiedTime();
     entries.push_back(entry);
   }
   content::BrowserThread::PostTask(content::BrowserThread::IO,
                                    FROM_HERE,
                                    base::Bind(success_callback, entries));
 }
 
 void MTPDeviceTaskHelper::OnGetFileInfoToReadBytes(
     const MTPDeviceAsyncDelegate::ReadBytesRequest& request,
     const MtpFileEntry& file_entry,
     bool error) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   DCHECK(request.buf);
-  DCHECK(request.buf_len >= 0);
+  DCHECK_GE(request.buf_len, 0);
   DCHECK_GE(request.offset, 0);
   if (error) {
     return HandleDeviceError(request.error_callback,
                              base::File::FILE_ERROR_FAILED);
   }
 
   base::File::Info file_info = FileInfoFromMTPFileEntry(file_entry);
   if (file_info.is_directory) {
     return HandleDeviceError(request.error_callback,
                              base::File::FILE_ERROR_NOT_A_FILE);
   } else if (file_info.size < 0 || file_info.size > kuint32max ||
              request.offset > file_info.size) {
     return HandleDeviceError(request.error_callback,
                              base::File::FILE_ERROR_FAILED);
   } else if (request.offset == file_info.size) {
     content::BrowserThread::PostTask(content::BrowserThread::IO,
                                      FROM_HERE,
                                      base::Bind(request.success_callback,
                                                 file_info, 0u));
     return;
   }
 
   uint32 bytes_to_read = std::min(
       base::checked_cast<uint32>(request.buf_len),
       base::saturated_cast<uint32>(file_info.size - request.offset));
 
-  GetMediaTransferProtocolManager()->ReadFileChunkByPath(
+  GetMediaTransferProtocolManager()->ReadFileChunkById(
       device_handle_,
-      request.device_file_relative_path,
+      request.file_id,
       base::checked_cast<uint32>(request.offset),
       bytes_to_read,
       base::Bind(&MTPDeviceTaskHelper::OnDidReadBytes,
                  weak_ptr_factory_.GetWeakPtr(), request, file_info));
 }
 
 void MTPDeviceTaskHelper::OnDidReadBytes(
     const MTPDeviceAsyncDelegate::ReadBytesRequest& request,
     const base::File::Info& file_info,
     const std::string& data,
@@ skipping 14 matching lines @@
 }
 
 void MTPDeviceTaskHelper::HandleDeviceError(
     const ErrorCallback& error_callback,
     base::File::Error error) const {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   content::BrowserThread::PostTask(content::BrowserThread::IO,
                                    FROM_HERE,
                                    base::Bind(error_callback, error));
 }