1 /*
2  * Copyright (C) 2012 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 /*
18  *  Asynchronous interval timer.
19  */
20 
21 #include "IntervalTimer.h"
22 
23 #include <android-base/stringprintf.h>
24 #include <base/logging.h>
25 
26 using android::base::StringPrintf;
27 
IntervalTimer()28 IntervalTimer::IntervalTimer() {
29   mTimerId = 0;
30   mCb = NULL;
31 }
32 
set(int ms,TIMER_FUNC cb)33 bool IntervalTimer::set(int ms, TIMER_FUNC cb) {
34   if (mTimerId == 0) {
35     if (cb == NULL) return false;
36 
37     if (!create(cb)) return false;
38   }
39   if (cb != mCb) {
40     kill();
41     if (!create(cb)) return false;
42   }
43 
44   int stat = 0;
45   struct itimerspec ts;
46   ts.it_value.tv_sec = ms / 1000;
47   ts.it_value.tv_nsec = (ms % 1000) * 1000000;
48 
49   ts.it_interval.tv_sec = 0;
50   ts.it_interval.tv_nsec = 0;
51 
52   stat = timer_settime(mTimerId, 0, &ts, 0);
53   if (stat == -1) LOG(ERROR) << StringPrintf("fail set timer");
54   return stat == 0;
55 }
56 
~IntervalTimer()57 IntervalTimer::~IntervalTimer() { kill(); }
58 
kill()59 void IntervalTimer::kill() {
60   if (mTimerId == 0) return;
61 
62   timer_delete(mTimerId);
63   mTimerId = 0;
64   mCb = NULL;
65 }
66 
create(TIMER_FUNC cb)67 bool IntervalTimer::create(TIMER_FUNC cb) {
68   struct sigevent se;
69   int stat = 0;
70 
71   /*
72    * Set the sigevent structure to cause the signal to be
73    * delivered by creating a new thread.
74    */
75   se.sigev_notify = SIGEV_THREAD;
76   se.sigev_value.sival_ptr = &mTimerId;
77   se.sigev_notify_function = cb;
78   se.sigev_notify_attributes = NULL;
79   se.sigev_signo = 0;
80   mCb = cb;
81   stat = timer_create(CLOCK_MONOTONIC, &se, &mTimerId);
82   if (stat == -1) LOG(ERROR) << StringPrintf("fail create timer");
83   return stat == 0;
84 }
85