Enabling creating of file_ref from filesystem and path for external filesystem.

At the moment file_ref will not get created for external file systems, which
makes nacl plugin unable to access files on external file system, event when it
owning render process has needed permissions (e.g. if renderer is running
file browser extension)

BUG=chromium-os:20497
TEST=On ChromeOS, Cr48: Made sure extension with fileBrowserHandler permission is able to read a file from local disk.
Also, checked that an extension without required privileges fails opening the file with PP_ERROR_NOACCESS error code.

Review URL: http://codereview.chromium.org/7982041

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@102875 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 44 insertions, 28 deletions

diff --git a/webkit/plugins/ppapi/ppb_file_io_impl.cc b/webkit/plugins/ppapi/ppb_file_io_impl.cc
index b074596..1460b27 100644
--- a/webkit/plugins/ppapi/ppb_file_io_impl.cc
+++ b/webkit/plugins/ppapi/ppb_file_io_impl.cc
@@ -86,24 +86,25 @@ int32_t PPB_FileIO_Impl::Open(PP_Resource pp_file_ref,
     return false;
 
   file_system_type_ = file_ref->GetFileSystemType();
-  switch (file_system_type_) {
-    case PP_FILESYSTEMTYPE_EXTERNAL:
-      if (!plugin_delegate->AsyncOpenFile(
-              file_ref->GetSystemPath(), flags,
-              callback_factory_.NewCallback(
-                  &PPB_FileIO_Impl::AsyncOpenFileCallback)))
-        return PP_ERROR_FAILED;
-      break;
-    case PP_FILESYSTEMTYPE_LOCALPERSISTENT:
-    case PP_FILESYSTEMTYPE_LOCALTEMPORARY:
-      file_system_url_ = file_ref->GetFileSystemURL();
-      if (!plugin_delegate->AsyncOpenFileSystemURL(
-              file_system_url_, flags,
-              callback_factory_.NewCallback(
-                  &PPB_FileIO_Impl::AsyncOpenFileCallback)))
-        return PP_ERROR_FAILED;
-      break;
-    default:
+  if (file_system_type_ != PP_FILESYSTEMTYPE_LOCALPERSISTENT &&
+      file_system_type_ != PP_FILESYSTEMTYPE_LOCALTEMPORARY &&
+      file_system_type_ != PP_FILESYSTEMTYPE_EXTERNAL)
+    return PP_ERROR_FAILED;
+
+  if (file_ref->HasValidFileSystem()) {
+    file_system_url_ = file_ref->GetFileSystemURL();
+    if (!plugin_delegate->AsyncOpenFileSystemURL(
+            file_system_url_, flags,
+            callback_factory_.NewCallback(
+                &PPB_FileIO_Impl::AsyncOpenFileCallback)))
+      return PP_ERROR_FAILED;
+  } else {
+    if (file_system_type_ != PP_FILESYSTEMTYPE_EXTERNAL)
+      return PP_ERROR_FAILED;
+    if (!plugin_delegate->AsyncOpenFile(
+            file_ref->GetSystemPath(), flags,
+            callback_factory_.NewCallback(
+                &PPB_FileIO_Impl::AsyncOpenFileCallback)))
       return PP_ERROR_FAILED;
   }
 
diff --git a/webkit/plugins/ppapi/ppb_file_ref_impl.cc b/webkit/plugins/ppapi/ppb_file_ref_impl.cc
index 7c43ba4..673ec01 100644
--- a/webkit/plugins/ppapi/ppb_file_ref_impl.cc
+++ b/webkit/plugins/ppapi/ppb_file_ref_impl.cc
@@ -108,7 +108,8 @@ PPB_FileRef_Impl* PPB_FileRef_Impl::CreateInternal(PP_Resource pp_file_system,
     return 0;
 
   if (file_system->type() != PP_FILESYSTEMTYPE_LOCALPERSISTENT &&
-      file_system->type() != PP_FILESYSTEMTYPE_LOCALTEMPORARY)
+      file_system->type() != PP_FILESYSTEMTYPE_LOCALTEMPORARY &&
+      file_system->type() != PP_FILESYSTEMTYPE_EXTERNAL)
     return 0;
 
   PPB_FileRef_CreateInfo info;
@@ -253,7 +254,8 @@ FilePath PPB_FileRef_Impl::GetSystemPath() const {
 
 GURL PPB_FileRef_Impl::GetFileSystemURL() const {
   if (GetFileSystemType() != PP_FILESYSTEMTYPE_LOCALPERSISTENT &&
-      GetFileSystemType() != PP_FILESYSTEMTYPE_LOCALTEMPORARY) {
+      GetFileSystemType() != PP_FILESYSTEMTYPE_LOCALTEMPORARY &&
+      GetFileSystemType() != PP_FILESYSTEMTYPE_EXTERNAL) {
     NOTREACHED();
     return GURL();
   }
@@ -269,6 +271,10 @@ GURL PPB_FileRef_Impl::GetFileSystemURL() const {
   return GURL(file_system_->root_url().spec() + virtual_path.substr(1));
 }
 
+bool PPB_FileRef_Impl::HasValidFileSystem() const {
+  return file_system_ && file_system_->opened();
+}
+
 bool PPB_FileRef_Impl::IsValidNonExternalFileSystem() const {
   return file_system_ && file_system_->opened() &&
       file_system_->type() != PP_FILESYSTEMTYPE_EXTERNAL;
diff --git a/webkit/plugins/ppapi/ppb_file_ref_impl.h b/webkit/plugins/ppapi/ppb_file_ref_impl.h
index de1649d..64926de 100644
--- a/webkit/plugins/ppapi/ppb_file_ref_impl.h
+++ b/webkit/plugins/ppapi/ppb_file_ref_impl.h
@@ -53,6 +53,8 @@ class PPB_FileRef_Impl : public ::ppapi::FileRefImpl {
   // Returns the FileSystem API URL corresponding to this file.
   GURL GetFileSystemURL() const;
 
+  // Checks if file ref has file system instance and if the instance is opened.
+  bool HasValidFileSystem() const;
  private:
   // Many mutation functions are allow only to non-external filesystems, This
   // function returns true if the filesystem is opened and isn't external as an
diff --git a/webkit/plugins/ppapi/ppb_file_system_impl.cc b/webkit/plugins/ppapi/ppb_file_system_impl.cc
index a63e954..b7576bc 100644
--- a/webkit/plugins/ppapi/ppb_file_system_impl.cc
+++ b/webkit/plugins/ppapi/ppb_file_system_impl.cc
@@ -61,18 +61,25 @@ int32_t PPB_FileSystem_Impl::Open(int64_t expected_size,
     return PP_ERROR_INPROGRESS;
   called_open_ = true;
 
-  if (type_ != PP_FILESYSTEMTYPE_LOCALPERSISTENT &&
-      type_ != PP_FILESYSTEMTYPE_LOCALTEMPORARY)
-    return PP_ERROR_FAILED;
+  fileapi::FileSystemType file_system_type;
+  switch (type_) {
+    case PP_FILESYSTEMTYPE_LOCALTEMPORARY:
+      file_system_type = fileapi::kFileSystemTypeTemporary;
+      break;
+    case PP_FILESYSTEMTYPE_LOCALPERSISTENT:
+      file_system_type = fileapi::kFileSystemTypePersistent;
+      break;
+    case PP_FILESYSTEMTYPE_EXTERNAL:
+      file_system_type = fileapi::kFileSystemTypeExternal;
+      break;
+    default:
+      return PP_ERROR_FAILED;
+  }
 
-  PluginInstance* plugin_instance = ResourceHelper::GetPluginInstance(this);
+ PluginInstance* plugin_instance = ResourceHelper::GetPluginInstance(this);
   if (!plugin_instance)
     return PP_ERROR_FAILED;
 
-  fileapi::FileSystemType file_system_type =
-      (type_ == PP_FILESYSTEMTYPE_LOCALTEMPORARY ?
-       fileapi::kFileSystemTypeTemporary :
-       fileapi::kFileSystemTypePersistent);
   if (!plugin_instance->delegate()->OpenFileSystem(
           plugin_instance->container()->element().document().url(),
           file_system_type, expected_size,