mojo filesystem: Further clean ups.

components/filesystem/file_system_app.cc

Index: components/filesystem/file_system_app.cc
diff --git a/components/filesystem/file_system_app.cc b/components/filesystem/file_system_app.cc
index d5d577aa18555cabe8274ab8c12a23303132a4c9..988d4eca3fc230667de28f19a85f5eeb4668b012 100644
--- a/components/filesystem/file_system_app.cc
+++ b/components/filesystem/file_system_app.cc
@@ -4,11 +4,35 @@
 
 #include "components/filesystem/file_system_app.h"
 
+#include "base/command_line.h"
+#include "base/files/file_path.h"
+#include "base/files/file_util.h"
 #include "mojo/shell/public/cpp/connection.h"
 #include "mojo/shell/public/cpp/shell.h"
 
+#if defined(OS_WIN)
+#include "base/base_paths_win.h"
+#include "base/path_service.h"
+#include "base/strings/utf_string_conversions.h"
+#elif defined(OS_ANDROID)
+#include "base/base_paths_android.h"
+#include "base/path_service.h"
+#elif defined(OS_LINUX)
+#include "base/environment.h"
+#include "base/nix/xdg_util.h"
+#elif defined(OS_MACOSX)
+#include "base/base_paths_mac.h"
+#include "base/path_service.h"
+#endif
+
 namespace filesystem {
 
+namespace {
+
+const char kUserDataDir[] = "user-data-dir";
+
+}  // namespace filesystem
+
 FileSystemApp::FileSystemApp()
     : shell_(nullptr), lock_table_(new LockTable) {}
 
@@ -28,7 +52,43 @@ bool FileSystemApp::AcceptConnection(mojo::Connection* connection) {
 // |InterfaceFactory<Files>| implementation:
 void FileSystemApp::Create(mojo::Connection* connection,
                            mojo::InterfaceRequest<FileSystem> request) {
-  new FileSystemImpl(connection, std::move(request), lock_table_.get());
+  new FileSystemImpl(connection, std::move(request), GetUserDataDir(),
+                     lock_table_.get());
+}
+
+//static
+base::FilePath FileSystemApp::GetUserDataDir() {
+  base::FilePath path;
+
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+  if (command_line->HasSwitch(kUserDataDir)) {
+    path = command_line->GetSwitchValuePath(kUserDataDir);
+  } else {
+#if defined(OS_WIN)
+    CHECK(PathService::Get(base::DIR_LOCAL_APP_DATA, &path));
+    path = path.Append(FILE_PATH_LITERAL("mandoline"));
+#elif defined(OS_LINUX)
+    scoped_ptr<base::Environment> env(base::Environment::Create());
+    base::FilePath config_dir(
+        base::nix::GetXDGDirectory(env.get(),
+                                   base::nix::kXdgConfigHomeEnvVar,
+                                   base::nix::kDotConfigDir));
+    path = config_dir.Append("mandoline");
+#elif defined(OS_MACOSX)
+    CHECK(PathService::Get(base::DIR_APP_DATA, &path));
+    path = path.Append("Mandoline Shell");
+#elif defined(OS_ANDROID)
+    CHECK(PathService::Get(base::DIR_ANDROID_APP_DATA, &path));
+    path = path.Append(FILE_PATH_LITERAL("mandoline"));
+#else
+    NOTIMPLEMENTED();
+#endif
+  }
+
+  if (!base::PathExists(path))
+    base::CreateDirectory(path);
+
+  return path;
 }
 
 }  // namespace filesystem