[PPAPI] Added pp::VarResource_Dev class.

This is a C++ wrapper for the C API PPB_VarResource_Dev.

Also added methods to pp::FileSystem for converting a pp::Resource to a
pp::FileSystem, which are necessary for making use of a resource
extracted using pp::VarResource_Dev.

(Committed by yzshen@chromium.org on behalf of mgiuca@chromium.org)

BUG=177017
R=dmichael@chromium.org, noelallen@chromium.org, noelallen@google.com, yzshen@chromium.org

Review URL: https://codereview.chromium.org/52233002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232482 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 18 insertions, 0 deletions

diff --git a/ppapi/cpp/file_system.cc b/ppapi/cpp/file_system.cc
index f993fda..8bd86d0 100644
--- a/ppapi/cpp/file_system.cc
+++ b/ppapi/cpp/file_system.cc
@@ -9,6 +9,7 @@
 #include "ppapi/cpp/completion_callback.h"
 #include "ppapi/cpp/file_ref.h"
 #include "ppapi/cpp/instance_handle.h"
+#include "ppapi/cpp/logging.h"
 #include "ppapi/cpp/module.h"
 #include "ppapi/cpp/module_impl.h"
 
@@ -28,6 +29,15 @@ FileSystem::FileSystem() {
 FileSystem::FileSystem(const FileSystem& other) : Resource(other) {
 }
 
+FileSystem::FileSystem(const Resource& resource) : Resource(resource) {
+  if (!IsFileSystem(resource)) {
+    PP_NOTREACHED();
+
+    // On release builds, set this to null.
+    Clear();
+  }
+}
+
 FileSystem::FileSystem(PassRef, PP_Resource resource)
     : Resource(PASS_REF, resource) {
 }
@@ -48,4 +58,12 @@ int32_t FileSystem::Open(int64_t expected_size,
       pp_resource(), expected_size, cc.pp_completion_callback());
 }
 
+// static
+bool FileSystem::IsFileSystem(const Resource& resource) {
+  if (!has_interface<PPB_FileSystem_1_0>())
+    return false;
+  return get_interface<PPB_FileSystem_1_0>()->IsFileSystem(
+      resource.pp_resource()) == PP_TRUE;
+}
+
 }  // namespace pp