Move DirectoryReader::ReadEntries to FileRef::ReadDirectoryEntries

This also means this API becomes a stable API.

While DirectoryReader was using the new pepper proxy API, FileRef is
using the old one. As updating FileRef would take some time, the
implementation of ReadEntries is converted from the new design to the
old one for now.

BUG=234513
TEST=browser_tests
R=avi@chromium.org, binji@chromium.org, dmichael@chromium.org, palmer@chromium.org, raymes@chromium.org, teravest@chromium.org

Review URL: https://codereview.chromium.org/14784002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198204 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 127 insertions, 0 deletions

diff --git a/ppapi/cpp/directory_entry.h b/ppapi/cpp/directory_entry.h
new file mode 100644
index 0000000..81be79e
--- /dev/null
+++ b/ppapi/cpp/directory_entry.h
@@ -0,0 +1,127 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef PPAPI_CPP_DIRECTORY_ENTRY_H_
+#define PPAPI_CPP_DIRECTORY_ENTRY_H_
+
+#include <vector>
+
+#include "ppapi/c/pp_array_output.h"
+#include "ppapi/c/pp_directory_entry.h"
+#include "ppapi/cpp/array_output.h"
+#include "ppapi/cpp/file_ref.h"
+#include "ppapi/cpp/output_traits.h"
+#include "ppapi/cpp/pass_ref.h"
+
+/// @file
+/// This file defines the API used to handle a directory entry.
+
+namespace pp {
+
+/// The <code>DirectoryEntry</code> class represents information about
+/// a directory entry.
+class DirectoryEntry {
+ public:
+  /// Default constructor for creating an is_null() <code>DirectoryEntry</code>
+  /// object.
+  DirectoryEntry();
+
+  /// A constructor used when you have a <code>PP_DirectoryEntry</code> which
+  /// contains a <code>FileRef</code> that has already been reference counted
+  /// as a return value.
+  ///
+  /// @param[in] data A <code>PP_DirectoryEntry</code> to be copied.
+  DirectoryEntry(PassRef, const PP_DirectoryEntry& data);
+
+  /// A copy constructor for <code>DirectoryEntry</code>. This constructor
+  /// increments a reference count of the <code>FileRef</code> held by this
+  /// DirectoryEntry.
+  ///
+  /// @param[in] other A pointer to a <code>DirectoryEntry</code>.
+  DirectoryEntry(const DirectoryEntry& other);
+
+  /// A destructor that decrements a reference count of the <code>FileRef</code>
+  /// held by this <code>DirectoryEntry</code>.
+  ~DirectoryEntry();
+
+  /// This function assigns one <code>DirectoryEntry</code> object to this
+  /// <code>DirectoryEntry</code> object. This function increases the reference
+  /// count of the <code>FileRef</code> of the other DirectoryEntry while
+  /// decrementing the reference count of the FileRef of this DirectoryEntry.
+  ///
+  /// @param[in] other A pointer to a <code>DirectoryEntry</code>.
+  ///
+  /// @return A new <code>DirectoryEntry</code> object.
+  DirectoryEntry& operator=(const DirectoryEntry& other);
+
+  /// This function determines if this <code>DirectoryEntry</code> is a null
+  /// value.
+  ///
+  /// @return true if this <code>DirectoryEntry</code> is null, otherwise false.
+  bool is_null() const { return !data_.file_ref; }
+
+  /// This function returns the <code>FileRef</code> held by this
+  /// <code>DirectoryEntry</code>.
+  ///
+  /// @return A <code>FileRef</code> of the file.
+  FileRef file_ref() const { return FileRef(data_.file_ref); }
+
+  /// This function returns the <code>PP_FileType</code> of the file referenced
+  /// by this <code>DirectoryEntry</code>.
+  ///
+  /// @return A <code>PP_FileType</code> of the file.
+  PP_FileType file_type() const { return data_.file_type; }
+
+ private:
+  PP_DirectoryEntry data_;
+};
+
+namespace internal {
+
+class DirectoryEntryArrayOutputAdapterWithStorage
+    : public ArrayOutputAdapter<PP_DirectoryEntry> {
+ public:
+  DirectoryEntryArrayOutputAdapterWithStorage();
+  virtual ~DirectoryEntryArrayOutputAdapterWithStorage();
+
+  // Returns the final array of resource objects, converting the
+  // PP_DirectoryEntry written by the browser to pp::DirectoryEntry
+  // objects.
+  //
+  // This function should only be called once or we would end up converting
+  // the array more than once, which would mess up the refcounting.
+  std::vector<DirectoryEntry>& output();
+
+ private:
+  // The browser will write the PP_DirectoryEntrys into this array.
+  std::vector<PP_DirectoryEntry> temp_storage_;
+
+  // When asked for the output, the PP_DirectoryEntrys above will be
+  // converted to the pp::DirectoryEntrys in this array for passing to the
+  // calling code.
+  std::vector<DirectoryEntry> output_storage_;
+};
+
+// A specialization of CallbackOutputTraits to provide the callback system the
+// information on how to handle vectors of pp::DirectoryEntry. This converts
+// PP_DirectoryEntry to pp::DirectoryEntry when passing to the plugin.
+template <>
+struct CallbackOutputTraits< std::vector<DirectoryEntry> > {
+  typedef PP_ArrayOutput APIArgType;
+  typedef DirectoryEntryArrayOutputAdapterWithStorage StorageType;
+
+  static inline APIArgType StorageToAPIArg(StorageType& t) {
+    return t.pp_array_output();
+  }
+
+  static inline std::vector<DirectoryEntry>& StorageToPluginArg(
+      StorageType& t) {
+    return t.output();
+  }
+};
+
+}  // namespace internal
+}  // namespace pp
+
+#endif  // PPAPI_CPP_DIRECTORY_ENTRY_H_