Cleanup: Add VirtualPath::IsRootPath()

BUG=241701
TEST=FileSystemUtilTest.IsRootPath
NOTRY=true
R=tzik@chromium.org

Review URL: https://codereview.chromium.org/18018002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@208889 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 26 insertions, 1 deletions

diff --git a/webkit/browser/fileapi/sandbox_mount_point_provider.cc b/webkit/browser/fileapi/sandbox_mount_point_provider.cc
index 2590007e..0c89438 100644
--- a/webkit/browser/fileapi/sandbox_mount_point_provider.cc
+++ b/webkit/browser/fileapi/sandbox_mount_point_provider.cc
@@ -281,7 +281,7 @@ FilePermissionPolicy SandboxMountPointProvider::GetPermissionPolicy(
     return FILE_PERMISSION_ALWAYS_DENY;
 
   // Any write access is disallowed on the root path.
-  if ((url.path().empty() || VirtualPath::DirName(url.path()) == url.path())
+  if (VirtualPath::IsRootPath(url.path())
       && (permissions & ~kReadFilePermissions))
     return FILE_PERMISSION_ALWAYS_DENY;
 
diff --git a/webkit/common/fileapi/file_system_util.cc b/webkit/common/fileapi/file_system_util.cc
index 2ce3c99..9ed0cd9 100644
--- a/webkit/common/fileapi/file_system_util.cc
+++ b/webkit/common/fileapi/file_system_util.cc
@@ -137,6 +137,14 @@ bool VirtualPath::IsAbsolute(const base::FilePath::StringType& path) {
   return path.find(kRoot) == 0;
 }
 
+bool VirtualPath::IsRootPath(const base::FilePath& path) {
+  std::vector<base::FilePath::StringType> components;
+  VirtualPath::GetComponents(path, &components);
+  return (path.empty() || components.empty() ||
+          (components.size() == 1 &&
+           components[0] == VirtualPath::kRoot));
+}
+
 GURL GetFileSystemRootURI(const GURL& origin_url, FileSystemType type) {
   // origin_url is based on a security origin, so http://foo.com or file:///
   // instead of the corresponding filesystem URL.
diff --git a/webkit/common/fileapi/file_system_util.h b/webkit/common/fileapi/file_system_util.h
index 1059f14..bf0cc85 100644
--- a/webkit/common/fileapi/file_system_util.h
+++ b/webkit/common/fileapi/file_system_util.h
@@ -59,6 +59,9 @@ class WEBKIT_STORAGE_COMMON_EXPORT VirtualPath {
 
   // Returns true if the given path begins with kRoot.
   static bool IsAbsolute(const base::FilePath::StringType& path);
+
+  // Returns true if the given path points to the root.
+  static bool IsRootPath(const base::FilePath& path);
 };
 
 // Returns the root URI of the filesystem that can be specified by a pair of
diff --git a/webkit/common/fileapi/file_system_util_unittest.cc b/webkit/common/fileapi/file_system_util_unittest.cc
index f1a03dd..6bb6d4f 100644
--- a/webkit/common/fileapi/file_system_util_unittest.cc
+++ b/webkit/common/fileapi/file_system_util_unittest.cc
@@ -121,6 +121,20 @@ TEST_F(FileSystemUtilTest, IsAbsolutePath) {
   EXPECT_FALSE(VirtualPath::IsAbsolute(FILE_PATH_LITERAL("foo/bar")));
 }
 
+TEST_F(FileSystemUtilTest, IsRootPath) {
+  EXPECT_TRUE(VirtualPath::IsRootPath(base::FilePath(FILE_PATH_LITERAL(""))));
+  EXPECT_TRUE(VirtualPath::IsRootPath(base::FilePath()));
+  EXPECT_TRUE(VirtualPath::IsRootPath(base::FilePath(FILE_PATH_LITERAL("/"))));
+  EXPECT_TRUE(VirtualPath::IsRootPath(base::FilePath(FILE_PATH_LITERAL("//"))));
+  EXPECT_FALSE(VirtualPath::IsRootPath(
+      base::FilePath(FILE_PATH_LITERAL("c:/"))));
+#if defined(FILE_PATH_USES_WIN_SEPARATORS)
+  EXPECT_TRUE(VirtualPath::IsRootPath(base::FilePath(FILE_PATH_LITERAL("\\"))));
+  EXPECT_FALSE(VirtualPath::IsRootPath(
+      base::FilePath(FILE_PATH_LITERAL("c:\\"))));
+#endif
+}
+
 TEST_F(FileSystemUtilTest, VirtualPathGetComponents) {
   struct test_data {
     const base::FilePath::StringType path;