You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 
hardware_samsung/exynos4/exynos4210/libsensors/InputEventReader.cpp

88 lines
2.3 KiB

/*
* Copyright (C) 2008 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 <stdint.h>
#include <errno.h>
#include <unistd.h>
#include <poll.h>
#include <sys/cdefs.h>
#include <sys/types.h>
#include <linux/input.h>
#include <cutils/log.h>
#include "InputEventReader.h"
/*****************************************************************************/
struct input_event;
InputEventCircularReader::InputEventCircularReader(size_t numEvents)
: mBuffer(new input_event[numEvents * 2]),
mBufferEnd(mBuffer + numEvents),
mHead(mBuffer),
mCurr(mBuffer),
mFreeSpace(numEvents)
{
}
InputEventCircularReader::~InputEventCircularReader()
{
delete [] mBuffer;
}
ssize_t InputEventCircularReader::fill(int fd)
{
size_t numEventsRead = 0;
if (mFreeSpace) {
const ssize_t nread = read(fd, mHead, mFreeSpace * sizeof(input_event));
if (nread<0 || nread % sizeof(input_event)) {
// we got a partial event!!
return nread<0 ? -errno : -EINVAL;
}
numEventsRead = nread / sizeof(input_event);
if (numEventsRead) {
mHead += numEventsRead;
mFreeSpace -= numEventsRead;
if (mHead > mBufferEnd) {
size_t s = mHead - mBufferEnd;
memcpy(mBuffer, mBufferEnd, s * sizeof(input_event));
mHead = mBuffer + s;
}
}
}
return numEventsRead;
}
ssize_t InputEventCircularReader::readEvent(input_event const** events)
{
*events = mCurr;
ssize_t available = (mBufferEnd - mBuffer) - mFreeSpace;
return available ? 1 : 0;
}
void InputEventCircularReader::next()
{
mCurr++;
mFreeSpace++;
if (mCurr >= mBufferEnd) {
mCurr = mBuffer;
}
}