/*
* Copyright (C) 2015 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.
*/
#define LOG_TAG "InputHub"
//#define LOG_NDEBUG 0
#include "InputHub.h"
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <sys/capability.h>
#include <sys/epoll.h>
#include <sys/eventfd.h>
#include <sys/inotify.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <unistd.h>
#include <vector>
#include <android/input.h>
#include <hardware_legacy/power.h>
#include <linux/input.h>
#include <utils/Log.h>
#include "BitUtils.h"
namespace android {
static const char WAKE_LOCK_ID[] = "KeyEvents";
static const int NO_TIMEOUT = -1;
static const int EPOLL_MAX_EVENTS = 16;
static const int INPUT_MAX_EVENTS = 128;
static constexpr bool testBit(int bit, const uint8_t arr[]) {
return arr[bit / 8] & (1 << (bit % 8));
}
static constexpr size_t sizeofBitArray(size_t bits) {
return (bits + 7) / 8;
}
static void getLinuxRelease(int* major, int* minor) {
struct utsname info;
if (uname(&info) || sscanf(info.release, "%d.%d", major, minor) <= 0) {
*major = 0, *minor = 0;
ALOGE("Could not get linux version: %s", strerror(errno));
}
}
class EvdevDeviceNode : public InputDeviceNode {
public:
static EvdevDeviceNode* openDeviceNode(const std::string& path);
virtual ~EvdevDeviceNode() {
ALOGV("closing %s (fd=%d)", mPath.c_str(), mFd);
if (mFd >= 0) {
::close(mFd);
}
}
virtual int getFd() const { return mFd; }
virtual const std::string& getPath() const override { return mPath; }
virtual const std::string& getName() const override { return mName; }
virtual const std::string& getLocation() const override { return mLocation; }
virtual const std::string& getUniqueId() const override { return mUniqueId; }
virtual uint16_t getBusType() const override { return mBusType; }
virtual uint16_t getVendorId() const override { return mVendorId; }
virtual uint16_t getProductId() const override { return mProductId; }
virtual uint16_t getVersion() const override { return mVersion; }
virtual bool hasKey(int32_t key) const override;
virtual bool hasKeyInRange(int32_t start, int32_t end) const override;
virtual bool hasRelativeAxis(int32_t axis) const override;
virtual bool hasAbsoluteAxis(int32_t axis) const override;
virtual bool hasSwitch(int32_t sw) const override;
virtual bool hasForceFeedback(int32_t ff) const override;
virtual bool hasInputProperty(int property) const override;
virtual int32_t getKeyState(int32_t key) const override;
virtual int32_t getSwitchState(int32_t sw) const override;
virtual const AbsoluteAxisInfo* getAbsoluteAxisInfo(int32_t axis) const override;
virtual status_t getAbsoluteAxisValue(int32_t axis, int32_t* outValue) const override;
virtual void vibrate(nsecs_t duration) override;
virtual void cancelVibrate() override;
virtual void disableDriverKeyRepeat() override;
private:
EvdevDeviceNode(const std::string& path, int fd) :
mFd(fd), mPath(path) {}
status_t queryProperties();
void queryAxisInfo();
int mFd;
std::string mPath;
std::string mName;
std::string mLocation;
std::string mUniqueId;
uint16_t mBusType;
uint16_t mVendorId;
uint16_t mProductId;
uint16_t mVersion;
uint8_t mKeyBitmask[KEY_CNT / 8];
uint8_t mAbsBitmask[ABS_CNT / 8];
uint8_t mRelBitmask[REL_CNT / 8];
uint8_t mSwBitmask[SW_CNT / 8];
uint8_t mLedBitmask[LED_CNT / 8];
uint8_t mFfBitmask[FF_CNT / 8];
uint8_t mPropBitmask[INPUT_PROP_CNT / 8];
std::unordered_map<uint32_t, std::unique_ptr<AbsoluteAxisInfo>> mAbsInfo;
bool mFfEffectPlaying = false;
int16_t mFfEffectId = -1;
};
EvdevDeviceNode* EvdevDeviceNode::openDeviceNode(const std::string& path) {
auto fd = TEMP_FAILURE_RETRY(::open(path.c_str(), O_RDONLY | O_NONBLOCK | O_CLOEXEC));
if (fd < 0) {
ALOGE("could not open evdev device %s. err=%d", path.c_str(), errno);
return nullptr;
}
// Tell the kernel that we want to use the monotonic clock for reporting
// timestamps associated with input events. This is important because the
// input system uses the timestamps extensively and assumes they were
// recorded using the monotonic clock.
//
// The EVIOCSCLOCKID ioctl was introduced in Linux 3.4.
int clockId = CLOCK_MONOTONIC;
if (TEMP_FAILURE_RETRY(ioctl(fd, EVIOCSCLOCKID, &clockId)) < 0) {
ALOGW("Could not set input clock id to CLOCK_MONOTONIC. errno=%d", errno);
}
auto node = new EvdevDeviceNode(path, fd);
status_t ret = node->queryProperties();
if (ret != OK) {
ALOGE("could not open evdev device %s: failed to read properties. errno=%d",
path.c_str(), ret);
delete node;
return nullptr;
}
return node;
}
status_t EvdevDeviceNode::queryProperties() {
char buffer[80];
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGNAME(sizeof(buffer) - 1), buffer)) < 1) {
ALOGV("could not get device name for %s.", mPath.c_str());
} else {
buffer[sizeof(buffer) - 1] = '\0';
mName = buffer;
}
int driverVersion;
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGVERSION, &driverVersion))) {
ALOGE("could not get driver version for %s. err=%d", mPath.c_str(), errno);
return -errno;
}
struct input_id inputId;
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGID, &inputId))) {
ALOGE("could not get device input id for %s. err=%d", mPath.c_str(), errno);
return -errno;
}
mBusType = inputId.bustype;
mVendorId = inputId.vendor;
mProductId = inputId.product;
mVersion = inputId.version;
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGPHYS(sizeof(buffer) - 1), buffer)) < 1) {
ALOGV("could not get location for %s.", mPath.c_str());
} else {
buffer[sizeof(buffer) - 1] = '\0';
mLocation = buffer;
}
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGUNIQ(sizeof(buffer) - 1), buffer)) < 1) {
ALOGV("could not get unique id for %s.", mPath.c_str());
} else {
buffer[sizeof(buffer) - 1] = '\0';
mUniqueId = buffer;
}
ALOGV("add device %s", mPath.c_str());
ALOGV(" bus: %04x\n"
" vendor: %04x\n"
" product: %04x\n"
" version: %04x\n",
mBusType, mVendorId, mProductId, mVersion);
ALOGV(" name: \"%s\"\n"
" location: \"%s\"\n"
" unique_id: \"%s\"\n"
" descriptor: (TODO)\n"
" driver: v%d.%d.%d",
mName.c_str(), mLocation.c_str(), mUniqueId.c_str(),
driverVersion >> 16, (driverVersion >> 8) & 0xff, (driverVersion >> 16) & 0xff);
TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGBIT(EV_KEY, sizeof(mKeyBitmask)), mKeyBitmask));
TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGBIT(EV_ABS, sizeof(mAbsBitmask)), mAbsBitmask));
TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGBIT(EV_REL, sizeof(mRelBitmask)), mRelBitmask));
TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGBIT(EV_SW, sizeof(mSwBitmask)), mSwBitmask));
TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGBIT(EV_LED, sizeof(mLedBitmask)), mLedBitmask));
TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGBIT(EV_FF, sizeof(mFfBitmask)), mFfBitmask));
TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGPROP(sizeof(mPropBitmask)), mPropBitmask));
queryAxisInfo();
return OK;
}
void EvdevDeviceNode::queryAxisInfo() {
for (int32_t axis = 0; axis < ABS_MAX; ++axis) {
if (testBit(axis, mAbsBitmask)) {
struct input_absinfo info;
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGABS(axis), &info))) {
ALOGW("Error reading absolute controller %d for device %s fd %d, errno=%d",
axis, mPath.c_str(), mFd, errno);
continue;
}
mAbsInfo[axis] = std::unique_ptr<AbsoluteAxisInfo>(new AbsoluteAxisInfo{
.minValue = info.minimum,
.maxValue = info.maximum,
.flat = info.flat,
.fuzz = info.fuzz,
.resolution = info.resolution
});
}
}
}
bool EvdevDeviceNode::hasKey(int32_t key) const {
if (key >= 0 && key <= KEY_MAX) {
return testBit(key, mKeyBitmask);
}
return false;
}
bool EvdevDeviceNode::hasKeyInRange(int32_t startKey, int32_t endKey) const {
return testBitInRange(mKeyBitmask, startKey, endKey);
}
bool EvdevDeviceNode::hasRelativeAxis(int axis) const {
if (axis >= 0 && axis <= REL_MAX) {
return testBit(axis, mRelBitmask);
}
return false;
}
bool EvdevDeviceNode::hasAbsoluteAxis(int axis) const {
if (axis >= 0 && axis <= ABS_MAX) {
return getAbsoluteAxisInfo(axis) != nullptr;
}
return false;
}
const AbsoluteAxisInfo* EvdevDeviceNode::getAbsoluteAxisInfo(int32_t axis) const {
if (axis < 0 || axis > ABS_MAX) {
return nullptr;
}
const auto absInfo = mAbsInfo.find(axis);
if (absInfo != mAbsInfo.end()) {
return absInfo->second.get();
}
return nullptr;
}
bool EvdevDeviceNode::hasSwitch(int32_t sw) const {
if (sw >= 0 && sw <= SW_MAX) {
return testBit(sw, mSwBitmask);
}
return false;
}
bool EvdevDeviceNode::hasForceFeedback(int32_t ff) const {
if (ff >= 0 && ff <= FF_MAX) {
return testBit(ff, mFfBitmask);
}
return false;
}
bool EvdevDeviceNode::hasInputProperty(int property) const {
if (property >= 0 && property <= INPUT_PROP_MAX) {
return testBit(property, mPropBitmask);
}
return false;
}
int32_t EvdevDeviceNode::getKeyState(int32_t key) const {
if (key >= 0 && key <= KEY_MAX) {
if (testBit(key, mKeyBitmask)) {
uint8_t keyState[sizeofBitArray(KEY_CNT)];
memset(keyState, 0, sizeof(keyState));
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGKEY(sizeof(keyState)), keyState)) >= 0) {
return testBit(key, keyState) ? AKEY_STATE_DOWN : AKEY_STATE_UP;
}
}
}
return AKEY_STATE_UNKNOWN;
}
int32_t EvdevDeviceNode::getSwitchState(int32_t sw) const {
if (sw >= 0 && sw <= SW_MAX) {
if (testBit(sw, mSwBitmask)) {
uint8_t swState[sizeofBitArray(SW_CNT)];
memset(swState, 0, sizeof(swState));
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGSW(sizeof(swState)), swState)) >= 0) {
return testBit(sw, swState) ? AKEY_STATE_DOWN : AKEY_STATE_UP;
}
}
}
return AKEY_STATE_UNKNOWN;
}
status_t EvdevDeviceNode::getAbsoluteAxisValue(int32_t axis, int32_t* outValue) const {
*outValue = 0;
if (axis >= 0 && axis <= ABS_MAX) {
if (testBit(axis, mAbsBitmask)) {
struct input_absinfo info;
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCGABS(axis), &info))) {
ALOGW("Error reading absolute controller %d for device %s fd %d, errno=%d",
axis, mPath.c_str(), mFd, errno);
return -errno;
}
*outValue = info.value;
return OK;
}
}
return -1;
}
void EvdevDeviceNode::vibrate(nsecs_t duration) {
ff_effect effect{};
effect.type = FF_RUMBLE;
effect.id = mFfEffectId;
effect.u.rumble.strong_magnitude = 0xc000;
effect.u.rumble.weak_magnitude = 0xc000;
effect.replay.length = (duration + 999'999LL) / 1'000'000LL;
effect.replay.delay = 0;
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCSFF, &effect))) {
ALOGW("Could not upload force feedback effect to device %s due to error %d.",
mPath.c_str(), errno);
return;
}
mFfEffectId = effect.id;
struct input_event ev{};
ev.type = EV_FF;
ev.code = mFfEffectId;
ev.value = 1;
size_t written = TEMP_FAILURE_RETRY(write(mFd, &ev, sizeof(ev)));
if (written != sizeof(ev)) {
ALOGW("Could not start force feedback effect on device %s due to error %d.",
mPath.c_str(), errno);
return;
}
mFfEffectPlaying = true;
}
void EvdevDeviceNode::cancelVibrate() {
if (mFfEffectPlaying) {
mFfEffectPlaying = false;
struct input_event ev{};
ev.type = EV_FF;
ev.code = mFfEffectId;
ev.value = 0;
size_t written = TEMP_FAILURE_RETRY(write(mFd, &ev, sizeof(ev)));
if (written != sizeof(ev)) {
ALOGW("Could not stop force feedback effect on device %s due to error %d.",
mPath.c_str(), errno);
return;
}
}
}
void EvdevDeviceNode::disableDriverKeyRepeat() {
unsigned int repeatRate[] = {0, 0};
if (TEMP_FAILURE_RETRY(ioctl(mFd, EVIOCSREP, repeatRate))) {
ALOGW("Unable to disable kernel key repeat for %s due to error %d.",
mPath.c_str(), errno);
}
}
InputHub::InputHub(const std::shared_ptr<InputCallbackInterface>& cb) :
mInputCallback(cb) {
// Determine the type of suspend blocking we can do on this device. There
// are 3 options, in decreasing order of preference:
// 1) EPOLLWAKEUP: introduced in Linux kernel 3.5, this flag can be set on
// an epoll event to indicate that a wake lock should be held from the
// time an fd has data until the next epoll_wait (or the epoll fd is
// closed).
// 2) EVIOCSSUSPENDBLOCK: introduced into the Android kernel's evdev
// driver, this ioctl blocks suspend while the event queue for the fd is
// not empty. This was never accepted into the mainline kernel, and it was
// replaced by EPOLLWAKEUP.
// 3) explicit wake locks: use acquire_wake_lock to manage suspend
// blocking explicitly in the InputHub code.
//
// (1) can be checked by simply observing the Linux kernel version. (2)
// requires an fd from an evdev node, which cannot be done in the InputHub
// constructor. So we assume (3) unless (1) is true, and we can verify
// whether (2) is true once we have an evdev fd (and we're not in (1)).
int major, minor;
getLinuxRelease(&major, &minor);
if (major > 3 || (major == 3 && minor >= 5)) {
ALOGI("Using EPOLLWAKEUP to block suspend while processing input events.");
mWakeupMechanism = WakeMechanism::EPOLL_WAKEUP;
mNeedToCheckSuspendBlockIoctl = false;
}
if (manageWakeLocks()) {
acquire_wake_lock(PARTIAL_WAKE_LOCK, WAKE_LOCK_ID);
}
// epoll_create argument is ignored, but it must be > 0.
mEpollFd = epoll_create(1);
LOG_ALWAYS_FATAL_IF(mEpollFd < 0, "Could not create epoll instance. errno=%d", errno);
mINotifyFd = inotify_init();
LOG_ALWAYS_FATAL_IF(mINotifyFd < 0, "Could not create inotify instance. errno=%d", errno);
struct epoll_event eventItem;
memset(&eventItem, 0, sizeof(eventItem));
eventItem.events = EPOLLIN;
if (mWakeupMechanism == WakeMechanism::EPOLL_WAKEUP) {
eventItem.events |= EPOLLWAKEUP;
}
eventItem.data.u32 = mINotifyFd;
int result = epoll_ctl(mEpollFd, EPOLL_CTL_ADD, mINotifyFd, &eventItem);
LOG_ALWAYS_FATAL_IF(result != 0, "Could not add INotify to epoll instance. errno=%d", errno);
int wakeFds[2];
result = pipe(wakeFds);
LOG_ALWAYS_FATAL_IF(result != 0, "Could not create wake pipe. errno=%d", errno);
mWakeEventFd = eventfd(0, EFD_NONBLOCK);
LOG_ALWAYS_FATAL_IF(mWakeEventFd == -1, "Could not create wake event fd. errno=%d", errno);
eventItem.data.u32 = mWakeEventFd;
result = epoll_ctl(mEpollFd, EPOLL_CTL_ADD, mWakeEventFd, &eventItem);
LOG_ALWAYS_FATAL_IF(result != 0, "Could not add wake event fd to epoll instance. errno=%d", errno);
}
InputHub::~InputHub() {
::close(mEpollFd);
::close(mINotifyFd);
::close(mWakeEventFd);
if (manageWakeLocks()) {
release_wake_lock(WAKE_LOCK_ID);
}
}
status_t InputHub::registerDevicePath(const std::string& path) {
ALOGV("registering device path %s", path.c_str());
int wd = inotify_add_watch(mINotifyFd, path.c_str(), IN_DELETE | IN_CREATE);
if (wd < 0) {
ALOGE("Could not add %s to INotify watch. errno=%d", path.c_str(), errno);
return -errno;
}
mWatchedPaths[wd] = path;
scanDir(path);
return OK;
}
status_t InputHub::unregisterDevicePath(const std::string& path) {
int wd = -1;
for (auto pair : mWatchedPaths) {
if (pair.second == path) {
wd = pair.first;
break;
}
}
if (wd == -1) {
return BAD_VALUE;
}
mWatchedPaths.erase(wd);
if (inotify_rm_watch(mINotifyFd, wd) != 0) {
return -errno;
}
return OK;
}
status_t InputHub::poll() {
bool deviceChange = false;
if (manageWakeLocks()) {
// Mind the wake lock dance!
// If we're relying on wake locks, we hold a wake lock at all times
// except during epoll_wait(). This works due to some subtle
// choreography. When a device driver has pending (unread) events, it
// acquires a kernel wake lock. However, once the last pending event
// has been read, the device driver will release the kernel wake lock.
// To prevent the system from going to sleep when this happens, the
// InputHub holds onto its own user wake lock while the client is
// processing events. Thus the system can only sleep if there are no
// events pending or currently being processed.
release_wake_lock(WAKE_LOCK_ID);
}
struct epoll_event pendingEventItems[EPOLL_MAX_EVENTS];
int pollResult = epoll_wait(mEpollFd, pendingEventItems, EPOLL_MAX_EVENTS, NO_TIMEOUT);
if (manageWakeLocks()) {
acquire_wake_lock(PARTIAL_WAKE_LOCK, WAKE_LOCK_ID);
}
if (pollResult == 0) {
ALOGW("epoll_wait should not return 0 with no timeout");
return UNKNOWN_ERROR;
}
if (pollResult < 0) {
// An error occurred. Return even if it's EINTR, and let the caller
// restart the poll.
ALOGE("epoll_wait returned with errno=%d", errno);
return -errno;
}
// pollResult > 0: there are events to process
nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
std::vector<int> removedDeviceFds;
int inputFd = -1;
std::shared_ptr<InputDeviceNode> deviceNode;
for (int i = 0; i < pollResult; ++i) {
const struct epoll_event& eventItem = pendingEventItems[i];
int dataFd = static_cast<int>(eventItem.data.u32);
if (dataFd == mINotifyFd) {
if (eventItem.events & EPOLLIN) {
deviceChange = true;
} else {
ALOGW("Received unexpected epoll event 0x%08x for INotify.", eventItem.events);
}
continue;
}
if (dataFd == mWakeEventFd) {
if (eventItem.events & EPOLLIN) {
ALOGV("awoken after wake()");
uint64_t u;
ssize_t nRead = TEMP_FAILURE_RETRY(read(mWakeEventFd, &u, sizeof(uint64_t)));
if (nRead != sizeof(uint64_t)) {
ALOGW("Could not read event fd; waking anyway.");
}
} else {
ALOGW("Received unexpected epoll event 0x%08x for wake event.",
eventItem.events);
}
continue;
}
// Update the fd and device node when the fd changes. When several
// events are read back-to-back with the same fd, this saves many reads
// from the hash table.
if (inputFd != dataFd) {
inputFd = dataFd;
deviceNode = mDeviceNodes[inputFd];
}
if (deviceNode == nullptr) {
ALOGE("could not find device node for fd %d", inputFd);
continue;
}
if (eventItem.events & EPOLLIN) {
struct input_event ievs[INPUT_MAX_EVENTS];
for (;;) {
ssize_t readSize = TEMP_FAILURE_RETRY(read(inputFd, ievs, sizeof(ievs)));
if (readSize == 0 || (readSize < 0 && errno == ENODEV)) {
ALOGW("could not get event, removed? (fd: %d, size: %zd errno: %d)",
inputFd, readSize, errno);
removedDeviceFds.push_back(inputFd);
break;
} else if (readSize < 0) {
if (errno != EAGAIN && errno != EINTR) {
ALOGW("could not get event. errno=%d", errno);
}
break;
} else if (readSize % sizeof(input_event) != 0) {
ALOGE("could not get event. wrong size=%zd", readSize);
break;
} else {
size_t count = static_cast<size_t>(readSize) / sizeof(struct input_event);
for (size_t i = 0; i < count; ++i) {
auto& iev = ievs[i];
auto when = s2ns(iev.time.tv_sec) + us2ns(iev.time.tv_usec);
InputEvent inputEvent = { when, iev.type, iev.code, iev.value };
mInputCallback->onInputEvent(deviceNode, inputEvent, now);
}
}
}
} else if (eventItem.events & EPOLLHUP) {
ALOGI("Removing device fd %d due to epoll hangup event.", inputFd);
removedDeviceFds.push_back(inputFd);
} else {
ALOGW("Received unexpected epoll event 0x%08x for device fd %d",
eventItem.events, inputFd);
}
}
if (removedDeviceFds.size()) {
for (auto deviceFd : removedDeviceFds) {
auto deviceNode = mDeviceNodes[deviceFd];
if (deviceNode != nullptr) {
status_t ret = closeNodeByFd(deviceFd);
if (ret != OK) {
ALOGW("Could not close device with fd %d. errno=%d", deviceFd, ret);
} else {
mInputCallback->onDeviceRemoved(deviceNode);
}
}
}
}
if (deviceChange) {
readNotify();
}
return OK;
}
status_t InputHub::wake() {
ALOGV("wake() called");
uint64_t u = 1;
ssize_t nWrite = TEMP_FAILURE_RETRY(write(mWakeEventFd, &u, sizeof(uint64_t)));
if (nWrite != sizeof(uint64_t) && errno != EAGAIN) {
ALOGW("Could not write wake signal, errno=%d", errno);
return -errno;
}
return OK;
}
void InputHub::dump(String8& dump) {
// TODO
}
status_t InputHub::readNotify() {
char event_buf[512];
struct inotify_event* event;
ssize_t res = TEMP_FAILURE_RETRY(read(mINotifyFd, event_buf, sizeof(event_buf)));
if (res < static_cast<int>(sizeof(*event))) {
ALOGW("could not get inotify event, %s\n", strerror(errno));
return -errno;
}
size_t event_pos = 0;
while (res >= static_cast<int>(sizeof(*event))) {
event = reinterpret_cast<struct inotify_event*>(event_buf + event_pos);
if (event->len) {
std::string path = mWatchedPaths[event->wd];
path.append("/").append(event->name);
ALOGV("inotify event for path %s", path.c_str());
if (event->mask & IN_CREATE) {
auto deviceNode = openNode(path);
if (deviceNode == nullptr) {
ALOGE("could not open device node %s. err=%zd", path.c_str(), res);
} else {
mInputCallback->onDeviceAdded(deviceNode);
}
} else {
auto deviceNode = findNodeByPath(path);
if (deviceNode != nullptr) {
status_t ret = closeNode(deviceNode.get());
if (ret != OK) {
ALOGW("Could not close device %s. errno=%d", path.c_str(), ret);
} else {
mInputCallback->onDeviceRemoved(deviceNode);
}
} else {
ALOGW("could not find device node for %s", path.c_str());
}
}
}
int event_size = sizeof(*event) + event->len;
res -= event_size;
event_pos += event_size;
}
return OK;
}
status_t InputHub::scanDir(const std::string& path) {
auto dir = ::opendir(path.c_str());
if (dir == nullptr) {
ALOGE("could not open device path %s to scan for devices. err=%d", path.c_str(), errno);
return -errno;
}
while (auto dirent = readdir(dir)) {
if (strcmp(dirent->d_name, ".") == 0 ||
strcmp(dirent->d_name, "..") == 0) {
continue;
}
std::string filename = path + "/" + dirent->d_name;
auto node = openNode(filename);
if (node == nullptr) {
ALOGE("could not open device node %s", filename.c_str());
} else {
mInputCallback->onDeviceAdded(node);
}
}
::closedir(dir);
return OK;
}
std::shared_ptr<InputDeviceNode> InputHub::openNode(const std::string& path) {
ALOGV("opening %s...", path.c_str());
auto evdevNode = std::shared_ptr<EvdevDeviceNode>(EvdevDeviceNode::openDeviceNode(path));
if (evdevNode == nullptr) {
return nullptr;
}
auto fd = evdevNode->getFd();
ALOGV("opened %s with fd %d", path.c_str(), fd);
mDeviceNodes[fd] = evdevNode;
struct epoll_event eventItem{};
eventItem.events = EPOLLIN;
if (mWakeupMechanism == WakeMechanism::EPOLL_WAKEUP) {
eventItem.events |= EPOLLWAKEUP;
}
eventItem.data.u32 = fd;
if (epoll_ctl(mEpollFd, EPOLL_CTL_ADD, fd, &eventItem)) {
ALOGE("Could not add device fd to epoll instance. errno=%d", errno);
return nullptr;
}
if (mNeedToCheckSuspendBlockIoctl) {
#ifndef EVIOCSSUSPENDBLOCK
// uapi headers don't include EVIOCSSUSPENDBLOCK, and future kernels
// will use an epoll flag instead, so as long as we want to support this
// feature, we need to be prepared to define the ioctl ourselves.
#define EVIOCSSUSPENDBLOCK _IOW('E', 0x91, int)
#endif
if (TEMP_FAILURE_RETRY(ioctl(fd, EVIOCSSUSPENDBLOCK, 1))) {
// no wake mechanism, continue using explicit wake locks
ALOGI("Using explicit wakelocks to block suspend while processing input events.");
} else {
mWakeupMechanism = WakeMechanism::LEGACY_EVDEV_SUSPENDBLOCK_IOCTL;
// release any held wakelocks since we won't need them anymore
release_wake_lock(WAKE_LOCK_ID);
ALOGI("Using EVIOCSSUSPENDBLOCK to block suspend while processing input events.");
}
mNeedToCheckSuspendBlockIoctl = false;
}
return evdevNode;
}
status_t InputHub::closeNode(const InputDeviceNode* node) {
for (auto pair : mDeviceNodes) {
if (pair.second.get() == node) {
return closeNodeByFd(pair.first);
}
}
return BAD_VALUE;
}
status_t InputHub::closeNodeByFd(int fd) {
status_t ret = OK;
if (epoll_ctl(mEpollFd, EPOLL_CTL_DEL, fd, NULL)) {
ALOGW("Could not remove device fd from epoll instance. errno=%d", errno);
ret = -errno;
}
mDeviceNodes.erase(fd);
::close(fd);
return ret;
}
std::shared_ptr<InputDeviceNode> InputHub::findNodeByPath(const std::string& path) {
for (auto pair : mDeviceNodes) {
if (pair.second->getPath() == path) return pair.second;
}
return nullptr;
}
bool InputHub::manageWakeLocks() const {
return mWakeupMechanism != WakeMechanism::EPOLL_WAKEUP;
}
} // namespace android