mediaview: Support watchers in ArcDocumentsProviderRoot.

chrome/browser/chromeos/arc/fileapi/arc_documents_provider_root.cc

 // Copyright 2016 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/chromeos/arc/fileapi/arc_documents_provider_root.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 77 matching lines @@
 
 void ArcDocumentsProviderRoot::ReadDirectory(
     const base::FilePath& path,
     const ReadDirectoryCallback& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   ResolveToDocumentId(
       path, base::Bind(&ArcDocumentsProviderRoot::ReadDirectoryWithDocumentId,
                        weak_ptr_factory_.GetWeakPtr(), callback));
 }
 
+void ArcDocumentsProviderRoot::AddWatcher(
+    const base::FilePath& path,
+    const WatcherCallback& watcher_callback,
+    const StatusCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  if (path_to_watcher_id_.count(path)) {
+    callback.Run(base::File::FILE_ERROR_FAILED);
+    return;
+  }
+  ResolveToDocumentId(
+      path, base::Bind(&ArcDocumentsProviderRoot::AddWatcherWithDocumentId,
+                       weak_ptr_factory_.GetWeakPtr(), path, watcher_callback,
+                       callback));
+}
+
+void ArcDocumentsProviderRoot::RemoveWatcher(const base::FilePath& path,
+                                             const StatusCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  auto iter = path_to_watcher_id_.find(path);
+  if (iter == path_to_watcher_id_.end()) {
+    callback.Run(base::File::FILE_ERROR_FAILED);
+    return;
+  }
+  int64_t watcher_id = iter->second;
+  path_to_watcher_id_.erase(iter);
+  file_system_operation_runner_util::RemoveWatcherOnIOThread(
+      watcher_id, base::Bind(&ArcDocumentsProviderRoot::RemoveWatcherDone,
+                             weak_ptr_factory_.GetWeakPtr(), callback));
+}
+
 void ArcDocumentsProviderRoot::ResolveToContentUrl(
     const base::FilePath& path,
     const ResolveToContentUrlCallback& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   ResolveToDocumentId(
       path,
       base::Bind(&ArcDocumentsProviderRoot::ResolveToContentUrlWithDocumentId,
                  weak_ptr_factory_.GetWeakPtr(), callback));
 }
 
@@ skipping 67 matching lines @@
   }
   EntryList entry_list;
   for (const auto& pair : mapping) {
     entry_list.emplace_back(pair.first, pair.second.is_directory
                                             ? storage::DirectoryEntry::DIRECTORY
                                             : storage::DirectoryEntry::FILE);
   }
   callback.Run(base::File::FILE_OK, entry_list, false /* has_more */);
 }
 
+void ArcDocumentsProviderRoot::AddWatcherWithDocumentId(
+    const base::FilePath& path,
+    const WatcherCallback& watcher_callback,
+    const StatusCallback& callback,
+    const std::string& document_id) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  if (document_id.empty()) {
+    callback.Run(base::File::FILE_ERROR_NOT_FOUND);
+    return;
+  }
+  file_system_operation_runner_util::AddWatcherOnIOThread(
+      authority_, document_id, watcher_callback,
+      base::Bind(&ArcDocumentsProviderRoot::AddWatcherDone,
+                 weak_ptr_factory_.GetWeakPtr(), path, callback));
+}
+
+void ArcDocumentsProviderRoot::AddWatcherDone(const base::FilePath& path,
+                                              const StatusCallback& callback,
+                                              int64_t watcher_id) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  if (watcher_id < 0) {
+    callback.Run(base::File::FILE_ERROR_FAILED);
+    return;
+  }
+  if (path_to_watcher_id_.count(path)) {
+    // Multiple watchers have been installed on the same file path in a race.
+    // Following the contract of WatcherManager, we reject all except the first.
+    file_system_operation_runner_util::RemoveWatcherOnIOThread(
+        watcher_id, base::Bind(&ArcDocumentsProviderRoot::AddWatcherAborted,
+                               weak_ptr_factory_.GetWeakPtr(), callback));
+    return;
+  }
+  path_to_watcher_id_.insert(std::make_pair(path, watcher_id));
+  callback.Run(base::File::FILE_OK);
+}
+
+void ArcDocumentsProviderRoot::AddWatcherAborted(const StatusCallback& callback,
+                                                 bool success) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  callback.Run(base::File::FILE_ERROR_FAILED);
+}
+
+void ArcDocumentsProviderRoot::RemoveWatcherDone(const StatusCallback& callback,
+                                                 bool success) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  callback.Run(success ? base::File::FILE_OK : base::File::FILE_ERROR_FAILED);
+}
+
 void ArcDocumentsProviderRoot::ResolveToContentUrlWithDocumentId(
     const ResolveToContentUrlCallback& callback,
     const std::string& document_id) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   if (document_id.empty()) {
     callback.Run(GURL());
     return;
   }
   callback.Run(BuildDocumentUrl(authority_, document_id));
 }
@@ skipping 96 matching lines @@
 
     mapping[filename] =
         ThinDocument{document->document_id,
                      document->mime_type == kAndroidDirectoryMimeType};
   }
 
   callback.Run(base::File::FILE_OK, std::move(mapping));
 }
 
 }  // namespace arc