blob: 81079fb54c15071d4be169c93abbb959e7a85c97 [file] [log] [blame]
* Copyright (c) 2020 The WebRTC project authors. All Rights Reserved.
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
#include "rtc_base/win/scoped_com_initializer.h"
#include "rtc_base/checks.h"
#include "rtc_base/logging.h"
namespace webrtc {
ScopedCOMInitializer::ScopedCOMInitializer() {
RTC_DLOG(INFO) << "Single-Threaded Apartment (STA) COM thread";
// Constructor for MTA initialization.
ScopedCOMInitializer::ScopedCOMInitializer(SelectMTA mta) {
RTC_DLOG(INFO) << "Multi-Threaded Apartment (MTA) COM thread";
ScopedCOMInitializer::~ScopedCOMInitializer() {
if (Succeeded()) {
void ScopedCOMInitializer::Initialize(COINIT init) {
// Initializes the COM library for use by the calling thread, sets the
// thread's concurrency model, and creates a new apartment for the thread
// if one is required. CoInitializeEx must be called at least once, and is
// usually called only once, for each thread that uses the COM library.
hr_ = CoInitializeEx(NULL, init);
<< "Invalid COM thread model change (MTA->STA)";
// Multiple calls to CoInitializeEx by the same thread are allowed as long
// as they pass the same concurrency flag, but subsequent valid calls
// return S_FALSE. To close the COM library gracefully on a thread, each
// successful call to CoInitializeEx, including any call that returns
// S_FALSE, must be balanced by a corresponding call to CoUninitialize.
if (hr_ == S_OK) {
<< "The COM library was initialized successfully on this thread";
} else if (hr_ == S_FALSE) {
<< "The COM library is already initialized on this thread";
} // namespace webrtc