1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <brillo/binder_watcher.h> 18 19 #include <base/bind.h> 20 #include <base/logging.h> 21 #include <binder/IPCThreadState.h> 22 #include <binder/ProcessState.h> 23 24 using android::IPCThreadState; 25 using android::ProcessState; 26 27 namespace { 28 // Called from the message loop whenever the binder file descriptor is ready. 29 void OnBinderReadReady() { 30 IPCThreadState::self()->handlePolledCommands(); 31 } 32 } // namespace 33 34 namespace brillo { 35 36 BinderWatcher::BinderWatcher(MessageLoop* message_loop) 37 : message_loop_(message_loop) {} 38 39 BinderWatcher::BinderWatcher() : message_loop_(nullptr) {} 40 41 BinderWatcher::~BinderWatcher() { 42 if (task_id_ != MessageLoop::kTaskIdNull) 43 message_loop_->CancelTask(task_id_); 44 } 45 46 bool BinderWatcher::Init() { 47 if (!message_loop_) 48 message_loop_ = MessageLoop::current(); 49 if (!message_loop_) { 50 LOG(ERROR) << "Must initialize a brillo::MessageLoop to use BinderWatcher"; 51 return false; 52 } 53 54 int binder_fd = -1; 55 ProcessState::self()->setThreadPoolMaxThreadCount(0); 56 IPCThreadState::self()->disableBackgroundScheduling(true); 57 int err = IPCThreadState::self()->setupPolling(&binder_fd); 58 if (err != 0) { 59 LOG(ERROR) << "Error setting up binder polling: " 60 << logging::SystemErrorCodeToString(err); 61 return false; 62 } 63 if (binder_fd < 0) { 64 LOG(ERROR) << "Invalid binder FD " << binder_fd; 65 return false; 66 } 67 VLOG(1) << "Got binder FD " << binder_fd; 68 69 task_id_ = message_loop_->WatchFileDescriptor( 70 FROM_HERE, 71 binder_fd, 72 MessageLoop::kWatchRead, 73 true /* persistent */, 74 base::Bind(&OnBinderReadReady)); 75 if (task_id_ == MessageLoop::kTaskIdNull) { 76 LOG(ERROR) << "Failed to watch binder FD"; 77 return false; 78 } 79 return true; 80 } 81 82 } // namespace brillo 83
