QUIC - cleanup changes to sync chromium tree with internal source.
[chromium-blink-merge.git] / ppapi / cpp / private / pass_file_handle.h
blobc25353b48389593fa880365dc13a012271f0d3b7
1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef PPAPI_CPP_PRIVATE_PASS_FILE_HANDLE_H_
6 #define PPAPI_CPP_PRIVATE_PASS_FILE_HANDLE_H_
8 #include <string.h>
10 #include "ppapi/c/private/pp_file_handle.h"
11 #include "ppapi/cpp/output_traits.h"
13 namespace pp {
15 // A wrapper class for PP_FileHandle to make sure a file handle is
16 // closed. This object takes the ownership of the file handle when it
17 // is constructed. This loses the ownership when this object is
18 // assigned to another object, just like auto_ptr.
19 class PassFileHandle {
20 public:
21 PassFileHandle();
22 // This constructor takes the ownership of |handle|.
23 explicit PassFileHandle(PP_FileHandle handle);
24 // Moves the ownership of |handle| to this object.
25 PassFileHandle(PassFileHandle& handle);
26 ~PassFileHandle();
28 // Releases |handle_|. The caller must close the file handle returned.
29 PP_FileHandle Release();
31 private:
32 // PassFileHandleRef allows users to return PassFileHandle as a
33 // value. This technique is also used by auto_ptr_ref.
34 struct PassFileHandleRef {
35 PP_FileHandle handle;
36 explicit PassFileHandleRef(PP_FileHandle h)
37 : handle(h) {
41 public:
42 PassFileHandle(PassFileHandleRef ref)
43 : handle_(ref.handle) {
46 operator PassFileHandleRef() {
47 return PassFileHandleRef(Release());
50 private:
51 void operator=(const PassFileHandle&);
53 void Close();
55 PP_FileHandle handle_;
58 namespace internal {
60 template<>
61 struct CallbackOutputTraits<PassFileHandle> {
62 typedef PP_FileHandle* APIArgType;
63 typedef PP_FileHandle StorageType;
65 static inline APIArgType StorageToAPIArg(StorageType& t) {
66 return &t;
69 static inline PassFileHandle StorageToPluginArg(StorageType& t) {
70 return PassFileHandle(t);
73 static inline void Initialize(StorageType* t) {
74 memset(t, 0, sizeof(*t));
78 } // namespace internal
79 } // namespace pp
81 #endif // PPAPI_CPP_PRIVATE_PASS_FILE_HANDLE_H_