| /* |
| * Copyright 2022 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "DrmEventListener.h" |
| |
| #include <linux/netlink.h> |
| #include <sys/socket.h> |
| |
| namespace aidl::android::hardware::graphics::composer3::impl { |
| |
| std::unique_ptr<DrmEventListener> DrmEventListener::create(::android::base::borrowed_fd drmFd, |
| std::function<void()> callback) { |
| std::unique_ptr<DrmEventListener> listener(new DrmEventListener(std::move(callback))); |
| |
| if (!listener->init(drmFd)) { |
| return nullptr; |
| } |
| |
| return listener; |
| } |
| |
| bool DrmEventListener::init(::android::base::borrowed_fd drmFd) { |
| mEventFd = ::android::base::unique_fd(socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT)); |
| if (!mEventFd.ok()) { |
| ALOGE("Failed to open uevent socket: %s", strerror(errno)); |
| return false; |
| } |
| struct sockaddr_nl addr; |
| memset(&addr, 0, sizeof(addr)); |
| addr.nl_family = AF_NETLINK; |
| addr.nl_pid = 0; |
| addr.nl_groups = 0xFFFFFFFF; |
| |
| int ret = bind(mEventFd, (struct sockaddr*)&addr, sizeof(addr)); |
| if (ret) { |
| ALOGE("Failed to bind uevent socket: %s", strerror(errno)); |
| return false; |
| } |
| |
| FD_ZERO(&mMonitoredFds); |
| FD_SET(drmFd.get(), &mMonitoredFds); |
| FD_SET(mEventFd.get(), &mMonitoredFds); |
| mMaxMonitoredFd = std::max(drmFd.get(), mEventFd.get()); |
| |
| mThread = std::thread([this]() { threadLoop(); }); |
| |
| return true; |
| } |
| |
| void DrmEventListener::threadLoop() { |
| int ret; |
| do { |
| ret = select(mMaxMonitoredFd + 1, &mMonitoredFds, NULL, NULL, NULL); |
| } while (ret == -1 && errno == EINTR); |
| |
| if (!FD_ISSET(mEventFd.get(), &mMonitoredFds)) { |
| ALOGE("%s: DrmEventListevener event fd unset?", __FUNCTION__); |
| return; |
| } |
| |
| char buffer[1024]; |
| while (true) { |
| ret = read(mEventFd.get(), &buffer, sizeof(buffer)); |
| if (ret == 0) { |
| return; |
| } else if (ret < 0) { |
| ALOGE("Got error reading uevent %d", ret); |
| return; |
| } |
| |
| bool drmEvent = false, hotplugEvent = false; |
| for (int i = 0; i < ret;) { |
| char* event = buffer + i; |
| if (strcmp(event, "DEVTYPE=drm_minor")) { |
| drmEvent = true; |
| } else if (strcmp(event, "HOTPLUG=1")) { |
| hotplugEvent = true; |
| } |
| |
| i += strlen(event) + 1; |
| } |
| |
| if (drmEvent && hotplugEvent) { |
| DEBUG_LOG("DrmEventListener detected hotplug event ."); |
| mOnEventCallback(); |
| } |
| } |
| } |
| |
| } // namespace aidl::android::hardware::graphics::composer3::impl |