1 /*
2 * Copyright (C) 2016 The Android Open Source Project
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 #include "chre/platform/system_timer.h"
18
19 #include "chre/platform/log.h"
20 #include "chre/util/time.h"
21
22 #include <errno.h>
23 #include <signal.h>
24 #include <string.h>
25
26 namespace chre {
27
28 namespace {
29
30 constexpr uint64_t kOneSecondInNanoseconds = 1000000000;
31
NanosecondsToTimespec(uint64_t ns,struct timespec * ts)32 void NanosecondsToTimespec(uint64_t ns, struct timespec *ts) {
33 ts->tv_sec = ns / kOneSecondInNanoseconds;
34 ts->tv_nsec = ns % kOneSecondInNanoseconds;
35 }
36
37 } // anonymous namespace
38
systemTimerNotifyCallback(union sigval cookie)39 void SystemTimerBase::systemTimerNotifyCallback(union sigval cookie) {
40 SystemTimer *sysTimer = static_cast<SystemTimer *>(cookie.sival_ptr);
41 sysTimer->mCallback(sysTimer->mData);
42 }
43
SystemTimer()44 SystemTimer::SystemTimer() {}
45
~SystemTimer()46 SystemTimer::~SystemTimer() {
47 if (mInitialized) {
48 int ret = timer_delete(mTimerId);
49 if (ret != 0) {
50 LOGE("Couldn't delete timer: %s", strerror(errno));
51 }
52 mInitialized = false;
53 }
54 }
55
init()56 bool SystemTimer::init() {
57 if (mInitialized) {
58 LOGW("Tried re-initializing timer");
59 } else {
60 struct sigevent sigevt = {};
61 sigevt.sigev_notify = SIGEV_THREAD;
62 sigevt.sigev_value.sival_ptr = this;
63 sigevt.sigev_notify_function = systemTimerNotifyCallback;
64 sigevt.sigev_notify_attributes = nullptr;
65
66 int ret = timer_create(CLOCK_MONOTONIC, &sigevt, &mTimerId);
67 if (ret != 0) {
68 LOGE("Couldn't create timer: %s", strerror(errno));
69 } else {
70 mInitialized = true;
71 }
72 }
73
74 return mInitialized;
75 }
76
set(SystemTimerCallback * callback,void * data,Nanoseconds delay)77 bool SystemTimer::set(SystemTimerCallback *callback, void *data,
78 Nanoseconds delay) {
79 // 0 has a special meaning in POSIX, i.e. cancel the timer. In our API, a
80 // value of 0 just means fire right away.
81 if (delay.toRawNanoseconds() == 0) {
82 delay = Nanoseconds(1);
83 }
84
85 if (mInitialized) {
86 mCallback = callback;
87 mData = data;
88 return setInternal(delay.toRawNanoseconds());
89 } else {
90 return false;
91 }
92 }
93
cancel()94 bool SystemTimer::cancel() {
95 if (mInitialized) {
96 // Setting delay to 0 disarms the timer.
97 return setInternal(0);
98 } else {
99 return false;
100 }
101 }
102
isActive()103 bool SystemTimer::isActive() {
104 bool isActive = false;
105 if (mInitialized) {
106 struct itimerspec spec = {};
107 int ret = timer_gettime(mTimerId, &spec);
108 if (ret != 0) {
109 LOGE("Couldn't obtain current timer configuration: %s", strerror(errno));
110 }
111
112 isActive = (spec.it_value.tv_sec > 0 || spec.it_value.tv_nsec > 0);
113 }
114
115 return isActive;
116 }
117
setInternal(uint64_t delayNs)118 bool SystemTimerBase::setInternal(uint64_t delayNs) {
119 constexpr int kFlags = 0;
120 struct itimerspec spec = {};
121 bool success = false;
122
123 NanosecondsToTimespec(delayNs, &spec.it_value);
124 NanosecondsToTimespec(0, &spec.it_interval);
125
126 int ret = timer_settime(mTimerId, kFlags, &spec, nullptr);
127 if (ret != 0) {
128 LOGE("Couldn't set timer: %s", strerror(errno));
129 } else {
130 success = true;
131 }
132
133 return success;
134 }
135
136 } // namespace chre
137