1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/hal/gonk/UeventPoller.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,226 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* Copyright 2012 Mozilla Foundation and Mozilla contributors
1.6 + *
1.7 + * Licensed under the Apache License, Version 2.0 (the "License");
1.8 + * you may not use this file except in compliance with the License.
1.9 + * You may obtain a copy of the License at
1.10 + *
1.11 + * http://www.apache.org/licenses/LICENSE-2.0
1.12 + *
1.13 + * Unless required by applicable law or agreed to in writing, software
1.14 + * distributed under the License is distributed on an "AS IS" BASIS,
1.15 + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
1.16 + * See the License for the specific language governing permissions and
1.17 + * limitations under the License.
1.18 + */
1.19 +
1.20 +#include <errno.h>
1.21 +#include <fcntl.h>
1.22 +#include <pthread.h>
1.23 +#include <signal.h>
1.24 +#include <string.h>
1.25 +#include <strings.h>
1.26 +#include <unistd.h>
1.27 +
1.28 +#include <arpa/inet.h>
1.29 +#include <linux/types.h>
1.30 +#include <linux/netlink.h>
1.31 +#include <netinet/in.h>
1.32 +#include <sys/socket.h>
1.33 +
1.34 +#include "nsDebug.h"
1.35 +#include "base/message_loop.h"
1.36 +#include "mozilla/FileUtils.h"
1.37 +#include "nsAutoPtr.h"
1.38 +#include "nsThreadUtils.h"
1.39 +#include "nsXULAppAPI.h"
1.40 +
1.41 +#include "UeventPoller.h"
1.42 +
1.43 +namespace mozilla {
1.44 +namespace hal_impl {
1.45 +
1.46 +static void ShutdownUevent();
1.47 +
1.48 +class NetlinkPoller : public MessageLoopForIO::Watcher
1.49 +{
1.50 +public:
1.51 + NetlinkPoller() : mSocket(-1),
1.52 + mIOLoop(MessageLoopForIO::current())
1.53 + {
1.54 + }
1.55 +
1.56 + virtual ~NetlinkPoller() {}
1.57 +
1.58 + bool OpenSocket();
1.59 +
1.60 + virtual void OnFileCanReadWithoutBlocking(int fd);
1.61 +
1.62 + // no writing to the netlink socket
1.63 + virtual void OnFileCanWriteWithoutBlocking(int fd)
1.64 + {
1.65 + MOZ_CRASH("Must not write to netlink socket");
1.66 + }
1.67 +
1.68 + MessageLoopForIO *GetIOLoop () const { return mIOLoop; }
1.69 + void RegisterObserver(IUeventObserver *aObserver)
1.70 + {
1.71 + mUeventObserverList.AddObserver(aObserver);
1.72 + }
1.73 +
1.74 + void UnregisterObserver(IUeventObserver *aObserver)
1.75 + {
1.76 + mUeventObserverList.RemoveObserver(aObserver);
1.77 + if (mUeventObserverList.Length() == 0)
1.78 + ShutdownUevent(); // this will destroy self
1.79 + }
1.80 +
1.81 +private:
1.82 + ScopedClose mSocket;
1.83 + MessageLoopForIO* mIOLoop;
1.84 + MessageLoopForIO::FileDescriptorWatcher mReadWatcher;
1.85 +
1.86 + const static int kBuffsize = 64 * 1024;
1.87 + uint8_t mBuffer [kBuffsize];
1.88 +
1.89 + typedef ObserverList<NetlinkEvent> UeventObserverList;
1.90 + UeventObserverList mUeventObserverList;
1.91 +};
1.92 +
1.93 +bool
1.94 +NetlinkPoller::OpenSocket()
1.95 +{
1.96 + mSocket.rwget() = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
1.97 + if (mSocket.get() < 0)
1.98 + return false;
1.99 +
1.100 + int sz = kBuffsize;
1.101 +
1.102 + if (setsockopt(mSocket.get(), SOL_SOCKET, SO_RCVBUFFORCE, &sz, sizeof(sz)) < 0)
1.103 + return false;
1.104 +
1.105 + // add FD_CLOEXEC flag
1.106 + int flags = fcntl(mSocket.get(), F_GETFD);
1.107 + if (flags == -1) {
1.108 + return false;
1.109 + }
1.110 + flags |= FD_CLOEXEC;
1.111 + if (fcntl(mSocket.get(), F_SETFD, flags) == -1)
1.112 + return false;
1.113 +
1.114 + // set non-blocking
1.115 + if (fcntl(mSocket.get(), F_SETFL, O_NONBLOCK) == -1)
1.116 + return false;
1.117 +
1.118 + struct sockaddr_nl saddr;
1.119 + bzero(&saddr, sizeof(saddr));
1.120 + saddr.nl_family = AF_NETLINK;
1.121 + saddr.nl_groups = 1;
1.122 + saddr.nl_pid = gettid();
1.123 +
1.124 + do {
1.125 + if (bind(mSocket.get(), (struct sockaddr *)&saddr, sizeof(saddr)) == 0) {
1.126 + break;
1.127 + }
1.128 +
1.129 + if (errno != EADDRINUSE) {
1.130 + return false;
1.131 + }
1.132 +
1.133 + if (saddr.nl_pid == 0) {
1.134 + return false;
1.135 + }
1.136 +
1.137 + // Once there was any other place in the same process assigning saddr.nl_pid by
1.138 + // gettid(), we can detect it and print warning message.
1.139 + printf_stderr("The netlink socket address saddr.nl_pid=%u is in use. Let the kernel re-assign.\n", saddr.nl_pid);
1.140 + saddr.nl_pid = 0;
1.141 + } while (true);
1.142 +
1.143 + if (!mIOLoop->WatchFileDescriptor(mSocket.get(),
1.144 + true,
1.145 + MessageLoopForIO::WATCH_READ,
1.146 + &mReadWatcher,
1.147 + this)) {
1.148 + return false;
1.149 + }
1.150 +
1.151 + return true;
1.152 +}
1.153 +
1.154 +static nsAutoPtr<NetlinkPoller> sPoller;
1.155 +
1.156 +class UeventInitTask : public Task
1.157 +{
1.158 + virtual void Run()
1.159 + {
1.160 + if (!sPoller) {
1.161 + return;
1.162 + }
1.163 + if (sPoller->OpenSocket()) {
1.164 + return;
1.165 + }
1.166 + sPoller->GetIOLoop()->PostDelayedTask(FROM_HERE, new UeventInitTask(), 1000);
1.167 + }
1.168 +};
1.169 +
1.170 +void
1.171 +NetlinkPoller::OnFileCanReadWithoutBlocking(int fd)
1.172 +{
1.173 + MOZ_ASSERT(fd == mSocket.get());
1.174 + while (true) {
1.175 + int ret = read(fd, mBuffer, kBuffsize);
1.176 + if (ret == -1) {
1.177 + if (errno == EAGAIN || errno == EWOULDBLOCK) {
1.178 + return;
1.179 + }
1.180 + if (errno == EINTR) {
1.181 + continue;
1.182 + }
1.183 + }
1.184 + if (ret <= 0) {
1.185 + // fatal error on netlink socket which should not happen
1.186 + _exit(1);
1.187 + }
1.188 + NetlinkEvent netlinkEvent;
1.189 + netlinkEvent.decode(reinterpret_cast<char*>(mBuffer), ret);
1.190 + mUeventObserverList.Broadcast(netlinkEvent);
1.191 + }
1.192 +}
1.193 +
1.194 +static void
1.195 +InitializeUevent()
1.196 +{
1.197 + MOZ_ASSERT(!sPoller);
1.198 + sPoller = new NetlinkPoller();
1.199 + sPoller->GetIOLoop()->PostTask(FROM_HERE, new UeventInitTask());
1.200 +
1.201 +}
1.202 +
1.203 +static void
1.204 +ShutdownUevent()
1.205 +{
1.206 + sPoller = nullptr;
1.207 +}
1.208 +
1.209 +void
1.210 +RegisterUeventListener(IUeventObserver *aObserver)
1.211 +{
1.212 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.213 +
1.214 + if (!sPoller)
1.215 + InitializeUevent();
1.216 + sPoller->RegisterObserver(aObserver);
1.217 +}
1.218 +
1.219 +void
1.220 +UnregisterUeventListener(IUeventObserver *aObserver)
1.221 +{
1.222 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.223 +
1.224 + sPoller->UnregisterObserver(aObserver);
1.225 +}
1.226 +
1.227 +} // hal_impl
1.228 +} // mozilla
1.229 +
