1// Copyright (c) 2012 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_process_information.h"
6
7#include "base/logging.h"
8#include "base/win/scoped_handle.h"
9
10namespace base {
11namespace win {
12
13namespace {
14
15// Duplicates source into target, returning true upon success. |target| is
16// guaranteed to be untouched in case of failure. Succeeds with no side-effects
17// if source is NULL.
18bool CheckAndDuplicateHandle(HANDLE source, ScopedHandle* target) {
19  if (!source)
20    return true;
21
22  HANDLE temp = NULL;
23  if (!::DuplicateHandle(::GetCurrentProcess(), source,
24                         ::GetCurrentProcess(), &temp, 0, FALSE,
25                         DUPLICATE_SAME_ACCESS)) {
26    DPLOG(ERROR) << "Failed to duplicate a handle.";
27    return false;
28  }
29  target->Set(temp);
30  return true;
31}
32
33}  // namespace
34
35ScopedProcessInformation::ScopedProcessInformation()
36    : process_id_(0), thread_id_(0) {
37}
38
39ScopedProcessInformation::ScopedProcessInformation(
40    const PROCESS_INFORMATION& process_info) : process_id_(0), thread_id_(0) {
41  Set(process_info);
42}
43
44ScopedProcessInformation::~ScopedProcessInformation() {
45  Close();
46}
47
48bool ScopedProcessInformation::IsValid() const {
49  return process_id_ || process_handle_.Get() ||
50         thread_id_ || thread_handle_.Get();
51}
52
53void ScopedProcessInformation::Close() {
54  process_handle_.Close();
55  thread_handle_.Close();
56  process_id_ = 0;
57  thread_id_ = 0;
58}
59
60void ScopedProcessInformation::Set(const PROCESS_INFORMATION& process_info) {
61  if (IsValid())
62    Close();
63
64  process_handle_.Set(process_info.hProcess);
65  thread_handle_.Set(process_info.hThread);
66  process_id_ = process_info.dwProcessId;
67  thread_id_ = process_info.dwThreadId;
68}
69
70bool ScopedProcessInformation::DuplicateFrom(
71    const ScopedProcessInformation& other) {
72  DCHECK(!IsValid()) << "target ScopedProcessInformation must be NULL";
73  DCHECK(other.IsValid()) << "source ScopedProcessInformation must be valid";
74
75  if (CheckAndDuplicateHandle(other.process_handle(), &process_handle_) &&
76      CheckAndDuplicateHandle(other.thread_handle(), &thread_handle_)) {
77    process_id_ = other.process_id();
78    thread_id_ = other.thread_id();
79    return true;
80  }
81
82  return false;
83}
84
85PROCESS_INFORMATION ScopedProcessInformation::Take() {
86  PROCESS_INFORMATION process_information = {};
87  process_information.hProcess = process_handle_.Take();
88  process_information.hThread = thread_handle_.Take();
89  process_information.dwProcessId = process_id();
90  process_information.dwThreadId = thread_id();
91  process_id_ = 0;
92  thread_id_ = 0;
93
94  return process_information;
95}
96
97HANDLE ScopedProcessInformation::TakeProcessHandle() {
98  process_id_ = 0;
99  return process_handle_.Take();
100}
101
102HANDLE ScopedProcessInformation::TakeThreadHandle() {
103  thread_id_ = 0;
104  return thread_handle_.Take();
105}
106
107}  // namespace win
108}  // namespace base
109