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      1 /*
      2  * Copyright (C) 2018 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 #include <media/TimeCheck.h>
     19 
     20 namespace android {
     21 
     22 /* static */
     23 sp<TimeCheck::TimeCheckThread> TimeCheck::getTimeCheckThread()
     24 {
     25     static sp<TimeCheck::TimeCheckThread> sTimeCheckThread = new TimeCheck::TimeCheckThread();
     26     return sTimeCheckThread;
     27 }
     28 
     29 TimeCheck::TimeCheck(const char *tag, uint32_t timeoutMs)
     30     : mEndTimeNs(getTimeCheckThread()->startMonitoring(tag, timeoutMs))
     31 {
     32 }
     33 
     34 TimeCheck::~TimeCheck() {
     35     getTimeCheckThread()->stopMonitoring(mEndTimeNs);
     36 }
     37 
     38 TimeCheck::TimeCheckThread::~TimeCheckThread()
     39 {
     40     AutoMutex _l(mMutex);
     41     requestExit();
     42     mMonitorRequests.clear();
     43     mCond.signal();
     44 }
     45 
     46 nsecs_t TimeCheck::TimeCheckThread::startMonitoring(const char *tag, uint32_t timeoutMs) {
     47     Mutex::Autolock _l(mMutex);
     48     nsecs_t endTimeNs = systemTime() + milliseconds(timeoutMs);
     49     for (; mMonitorRequests.indexOfKey(endTimeNs) >= 0; ++endTimeNs);
     50     mMonitorRequests.add(endTimeNs, tag);
     51     mCond.signal();
     52     return endTimeNs;
     53 }
     54 
     55 void TimeCheck::TimeCheckThread::stopMonitoring(nsecs_t endTimeNs) {
     56     Mutex::Autolock _l(mMutex);
     57     mMonitorRequests.removeItem(endTimeNs);
     58     mCond.signal();
     59 }
     60 
     61 bool TimeCheck::TimeCheckThread::threadLoop()
     62 {
     63     status_t status = TIMED_OUT;
     64     const char *tag;
     65     {
     66         AutoMutex _l(mMutex);
     67 
     68         if (exitPending()) {
     69             return false;
     70         }
     71 
     72         nsecs_t endTimeNs = INT64_MAX;
     73         // KeyedVector mMonitorRequests is ordered so take first entry as next timeout
     74         if (mMonitorRequests.size() != 0) {
     75             endTimeNs = mMonitorRequests.keyAt(0);
     76             tag = mMonitorRequests.valueAt(0);
     77         }
     78 
     79         const nsecs_t waitTimeNs = endTimeNs - systemTime();
     80         if (waitTimeNs > 0) {
     81             status = mCond.waitRelative(mMutex, waitTimeNs);
     82         }
     83     }
     84     LOG_ALWAYS_FATAL_IF(status != NO_ERROR, "TimeCheck timeout for %s", tag);
     85     return true;
     86 }
     87 
     88 }; // namespace android
     89