Remove thread restriction of fileapi::FileSystemContext::ResolveURL.

BUG=363962

Review URL: https://codereview.chromium.org/242443004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@265179 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 48 insertions, 11 deletions

diff --git a/webkit/browser/fileapi/file_system_context.cc b/webkit/browser/fileapi/file_system_context.cc
index f6e7df3..847a68b 100644
--- a/webkit/browser/fileapi/file_system_context.cc
+++ b/webkit/browser/fileapi/file_system_context.cc
@@ -51,10 +51,29 @@ void DidGetMetadataForResolveURL(
     base::File::Error error,
     const base::File::Info& file_info) {
   if (error != base::File::FILE_OK) {
-    callback.Run(error, FileSystemInfo(), base::FilePath(), false);
+    if (error == base::File::FILE_ERROR_NOT_FOUND) {
+      callback.Run(base::File::FILE_OK, info, path,
+                   FileSystemContext::RESOLVED_ENTRY_NOT_FOUND);
+    } else {
+      callback.Run(error, FileSystemInfo(), base::FilePath(),
+                   FileSystemContext::RESOLVED_ENTRY_NOT_FOUND);
+    }
     return;
   }
-  callback.Run(error, info, path, file_info.is_directory);
+  callback.Run(error, info, path, file_info.is_directory ?
+      FileSystemContext::RESOLVED_ENTRY_DIRECTORY :
+      FileSystemContext::RESOLVED_ENTRY_FILE);
+}
+
+void RelayResolveURLCallback(
+    scoped_refptr<base::MessageLoopProxy> message_loop,
+    const FileSystemContext::ResolveURLCallback& callback,
+    base::File::Error result,
+    const FileSystemInfo& info,
+    const base::FilePath& file_path,
+    FileSystemContext::ResolvedEntryType type) {
+  message_loop->PostTask(
+      FROM_HERE, base::Bind(callback, result, info, file_path, type));
 }
 
 }  // namespace
@@ -322,15 +341,24 @@ void FileSystemContext::OpenFileSystem(
 void FileSystemContext::ResolveURL(
     const FileSystemURL& url,
     const ResolveURLCallback& callback) {
-  // TODO(nhiroki, kinuko): Remove this thread restriction, so it can be called
-  // on either UI or IO thread.
-  DCHECK(io_task_runner_->RunsTasksOnCurrentThread());
   DCHECK(!callback.is_null());
 
+  // If not on IO thread, forward before passing the task to the backend.
+  if (!io_task_runner_->RunsTasksOnCurrentThread()) {
+    ResolveURLCallback relay_callback =
+        base::Bind(&RelayResolveURLCallback,
+                   base::MessageLoopProxy::current(), callback);
+    io_task_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(&FileSystemContext::ResolveURL, this, url, relay_callback));
+    return;
+  }
+
   FileSystemBackend* backend = GetFileSystemBackend(url.type());
   if (!backend) {
     callback.Run(base::File::FILE_ERROR_SECURITY,
-                 FileSystemInfo(), base::FilePath(), false);
+                 FileSystemInfo(), base::FilePath(),
+                 FileSystemContext::RESOLVED_ENTRY_NOT_FOUND);
     return;
   }
 
@@ -560,7 +588,8 @@ void FileSystemContext::DidOpenFileSystemForResolveURL(
   DCHECK(io_task_runner_->RunsTasksOnCurrentThread());
 
   if (error != base::File::FILE_OK) {
-    callback.Run(error, FileSystemInfo(), base::FilePath(), false);
+    callback.Run(error, FileSystemInfo(), base::FilePath(),
+                 FileSystemContext::RESOLVED_ENTRY_NOT_FOUND);
     return;
   }
 
diff --git a/webkit/browser/fileapi/file_system_context.h b/webkit/browser/fileapi/file_system_context.h
index ba91af7..6e53981 100644
--- a/webkit/browser/fileapi/file_system_context.h
+++ b/webkit/browser/fileapi/file_system_context.h
@@ -188,10 +188,15 @@ class WEBKIT_STORAGE_BROWSER_EXPORT FileSystemContext
       OpenFileSystemCallback;
 
   // Used for ResolveURL.
+  enum ResolvedEntryType {
+    RESOLVED_ENTRY_FILE,
+    RESOLVED_ENTRY_DIRECTORY,
+    RESOLVED_ENTRY_NOT_FOUND,
+  };
   typedef base::Callback<void(base::File::Error result,
                               const FileSystemInfo& info,
                               const base::FilePath& file_path,
-                              bool is_directory)> ResolveURLCallback;
+                              ResolvedEntryType type)> ResolveURLCallback;
 
   // Used for DeleteFileSystem and OpenPluginPrivateFileSystem.
   typedef base::Callback<void(base::File::Error result)> StatusCallback;
@@ -207,9 +212,12 @@ class WEBKIT_STORAGE_BROWSER_EXPORT FileSystemContext
       OpenFileSystemMode mode,
       const OpenFileSystemCallback& callback);
 
-  // Opens the filesystem for the given |url| as read-only, and then checks the
-  // existence of the file entry referred by the URL. This should be called on
-  // the IO thread.
+  // Opens the filesystem for the given |url| as read-only, if the filesystem
+  // backend referred by the URL allows opening by resolveURL. Otherwise it
+  // fails with FILE_ERROR_SECURITY. The entry pointed by the URL can be
+  // absent; in that case RESOLVED_ENTRY_NOT_FOUND type is returned to the
+  // callback for indicating the absence. Can be called from any thread with
+  // a message loop. |callback| is invoked on the caller thread.
   void ResolveURL(
       const FileSystemURL& url,
       const ResolveURLCallback& callback);