1// Copyright (c) 2010 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.
4
5#include "base/win/scoped_bstr.h"
6
7#include "base/logging.h"
8
9namespace base {
10namespace win {
11
12ScopedBstr::ScopedBstr(const char16* non_bstr)
13    : bstr_(SysAllocString(non_bstr)) {
14}
15
16ScopedBstr::~ScopedBstr() {
17  COMPILE_ASSERT(sizeof(ScopedBstr) == sizeof(BSTR), ScopedBstrSize);
18  SysFreeString(bstr_);
19}
20
21void ScopedBstr::Reset(BSTR bstr) {
22  if (bstr != bstr_) {
23    // if |bstr_| is NULL, SysFreeString does nothing.
24    SysFreeString(bstr_);
25    bstr_ = bstr;
26  }
27}
28
29BSTR ScopedBstr::Release() {
30  BSTR bstr = bstr_;
31  bstr_ = NULL;
32  return bstr;
33}
34
35void ScopedBstr::Swap(ScopedBstr& bstr2) {
36  BSTR tmp = bstr_;
37  bstr_ = bstr2.bstr_;
38  bstr2.bstr_ = tmp;
39}
40
41BSTR* ScopedBstr::Receive() {
42  DCHECK(!bstr_) << "BSTR leak.";
43  return &bstr_;
44}
45
46BSTR ScopedBstr::Allocate(const char16* str) {
47  Reset(SysAllocString(str));
48  return bstr_;
49}
50
51BSTR ScopedBstr::AllocateBytes(size_t bytes) {
52  Reset(SysAllocStringByteLen(NULL, static_cast<UINT>(bytes)));
53  return bstr_;
54}
55
56void ScopedBstr::SetByteLen(size_t bytes) {
57  DCHECK(bstr_ != NULL) << "attempting to modify a NULL bstr";
58  uint32* data = reinterpret_cast<uint32*>(bstr_);
59  data[-1] = static_cast<uint32>(bytes);
60}
61
62size_t ScopedBstr::Length() const {
63  return SysStringLen(bstr_);
64}
65
66size_t ScopedBstr::ByteLength() const {
67  return SysStringByteLen(bstr_);
68}
69
70}  // namespace win
71}  // namespace base
72