1 /*
2 * Copyright (C) 2012 Invensense, Inc.
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 #define LOG_NDEBUG 0
18
19 #include <stdint.h>
20 #include <errno.h>
21 #include <unistd.h>
22 #include <poll.h>
23
24 #include <sys/cdefs.h>
25 #include <sys/types.h>
26
27 #include <linux/input.h>
28
29 #include <cutils/log.h>
30
31 #include "InputEventReader.h"
32
33 /*****************************************************************************/
34
35 struct input_event;
36
InputEventCircularReader(size_t numEvents)37 InputEventCircularReader::InputEventCircularReader(size_t numEvents)
38 : mBuffer(new input_event[numEvents * 2]),
39 mBufferEnd(mBuffer + numEvents),
40 mHead(mBuffer),
41 mCurr(mBuffer),
42 mFreeSpace(numEvents)
43 {
44 mLastFd = -1;
45 }
46
~InputEventCircularReader()47 InputEventCircularReader::~InputEventCircularReader()
48 {
49 delete [] mBuffer;
50 }
51
52 #define INPUT_EVENT_DEBUG (0)
fill(int fd)53 ssize_t InputEventCircularReader::fill(int fd)
54 {
55 size_t numEventsRead = 0;
56 mLastFd = fd;
57
58 LOGV_IF(INPUT_EVENT_DEBUG,
59 "DEBUG:%s enter, fd=%d\n", __PRETTY_FUNCTION__, fd);
60 if (mFreeSpace) {
61 const ssize_t nread = read(fd, mHead, mFreeSpace * sizeof(input_event));
62 if (nread < 0 || nread % sizeof(input_event)) {
63 //LOGE("Partial event received nread=%d, required=%d",
64 // nread, sizeof(input_event));
65 //LOGE("FD trying to read is: %d");
66 // we got a partial event!!
67 if (INPUT_EVENT_DEBUG) {
68 LOGV_IF(nread < 0, "DEBUG:%s exit nread < 0\n",
69 __PRETTY_FUNCTION__);
70 LOGV_IF(nread % sizeof(input_event),
71 "DEBUG:%s exit nread %% sizeof(input_event)\n",
72 __PRETTY_FUNCTION__);
73 }
74 return (nread < 0 ? -errno : -EINVAL);
75 }
76
77 numEventsRead = nread / sizeof(input_event);
78 if (numEventsRead) {
79 mHead += numEventsRead;
80 mFreeSpace -= numEventsRead;
81 if (mHead > mBufferEnd) {
82 size_t s = mHead - mBufferEnd;
83 memcpy(mBuffer, mBufferEnd, s * sizeof(input_event));
84 mHead = mBuffer + s;
85 }
86 }
87 }
88
89 LOGV_IF(INPUT_EVENT_DEBUG, "DEBUG:%s exit, numEventsRead:%d\n",
90 __PRETTY_FUNCTION__, numEventsRead);
91 return numEventsRead;
92 }
93
readEvent(input_event const ** events)94 ssize_t InputEventCircularReader::readEvent(input_event const** events)
95 {
96 *events = mCurr;
97 ssize_t available = (mBufferEnd - mBuffer) - mFreeSpace;
98 LOGV_IF(INPUT_EVENT_DEBUG, "DEBUG:%s fd:%d, available:%d\n",
99 __PRETTY_FUNCTION__, mLastFd, (int)available);
100 return (available ? 1 : 0);
101 }
102
next()103 void InputEventCircularReader::next()
104 {
105 mCurr++;
106 mFreeSpace++;
107 if (mCurr >= mBufferEnd) {
108 mCurr = mBuffer;
109 }
110 ssize_t available = (mBufferEnd - mBuffer) - mFreeSpace;
111 LOGV_IF(INPUT_EVENT_DEBUG, "DEBUG:%s fd:%d, still available:%d\n",
112 __PRETTY_FUNCTION__, mLastFd, (int)available);
113 }
114
115