1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include <windows.h>
#include "base/process_util.h"
#include "CrossProcessMutex.h"
#include "nsDebug.h"
#include "nsISupportsImpl.h"
#include "ProtocolUtils.h"
using base::GetCurrentProcessHandle;
using base::ProcessHandle;
namespace mozilla {
CrossProcessMutex::CrossProcessMutex(const char*) {
// We explicitly share this using DuplicateHandle, we do -not- want this to
// be inherited by child processes by default! So no security attributes are
// given.
mMutex = ::CreateMutexA(nullptr, FALSE, nullptr);
if (!mMutex) {
MOZ_CRASH("This shouldn't happen - failed to create mutex!");
}
MOZ_COUNT_CTOR(CrossProcessMutex);
}
CrossProcessMutex::CrossProcessMutex(CrossProcessMutexHandle aHandle) {
DWORD flags;
if (!::GetHandleInformation(aHandle, &flags)) {
MOZ_CRASH("Attempt to construct a mutex from an invalid handle!");
}
mMutex = aHandle;
MOZ_COUNT_CTOR(CrossProcessMutex);
}
CrossProcessMutex::~CrossProcessMutex() {
NS_ASSERTION(mMutex, "Improper construction of mutex or double free.");
::CloseHandle(mMutex);
MOZ_COUNT_DTOR(CrossProcessMutex);
}
void CrossProcessMutex::Lock() {
NS_ASSERTION(mMutex, "Improper construction of mutex.");
::WaitForSingleObject(mMutex, INFINITE);
}
void CrossProcessMutex::Unlock() {
NS_ASSERTION(mMutex, "Improper construction of mutex.");
::ReleaseMutex(mMutex);
}
CrossProcessMutexHandle CrossProcessMutex::ShareToProcess(
base::ProcessId aTargetPid) {
HANDLE newHandle;
bool succeeded = ipc::DuplicateHandle(mMutex, aTargetPid, &newHandle, 0,
DUPLICATE_SAME_ACCESS);
if (!succeeded) {
return nullptr;
}
return newHandle;
}
} // namespace mozilla
|
