/usr/share/doc/libaria-dev/examples/advanced/condition.cpp is in libaria-dev 2.8.0+repack-1.2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 | /*
Adept MobileRobots Robotics Interface for Applications (ARIA)
Copyright (C) 2004, 2005 ActivMedia Robotics LLC
Copyright (C) 2006, 2007, 2008, 2009, 2010 MobileRobots Inc.
Copyright (C) 2011, 2012, 2013 Adept Technology
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
If you wish to redistribute ARIA under different terms, contact
Adept MobileRobots for information about a commercial version of ARIA at
robots@mobilerobots.com or
Adept MobileRobots, 10 Columbia Drive, Amherst, NH 03031; +1-603-881-7960
*/
#include <stdlib.h>
#include <time.h>
#include "Aria.h"
/*
This example is to show how to use a condition variable. Conditions
are usefull for delaying the execution of a thread until some time later
when some other part of the program wants to wake it up.
This program has 5 threads. The main thread and 4 worker threads. The
worker threads all wait on the condition variable to be woken up. When
they are woken up they print that fact and then go right back to sleep
waiting on the condition variable.
The main thread randomly sleeps between 100ms and 500ms and then wakes
up a single thread. It does this 10 times then tells all the threads
to exit and waits for them to do so. The main thread then exits, which
ends the program.
This is simply an example of how to make threads wait for something to
happen without doing a busy loop, which takes up CPU time.
*/
// The thread class
class Task : public ArASyncTask
{
public:
Task(int num, ArCondition *cond);
virtual ~Task() {}
// The run loop of the thread.
void * runThread(void *arg);
protected:
int myNum;
ArCondition *myCond;
};
// Constructor
Task::Task(int num, ArCondition *cond) :
myNum(num),
myCond(cond)
{
setThreadName("Task");
}
// The main loop for the threads. It checks to see if its still running.
// If not, it exits. The running variable is managed by ArThread. While its
// running, it waits on the condition variable.
void * Task::runThread(void *arg)
{
threadStarted();
while (getRunning())
{
printf("Task %d waiting\n", myNum);
myCond->wait();
printf("Task %d woke up\n", myNum);
}
return(NULL);
}
int main()
{
int i, sleepTime;
// The condition the threads will be using
ArCondition cond;
// The threads
Task task1(1, &cond);
Task task2(2, &cond);
Task task3(3, &cond);
Task task4(4, &cond);
// Initialize Aria, which in turn initializes the thread layer
Aria::init();
// Initialize the rand() function
srand((unsigned)time(NULL));
// Lets start all correct threads.
task1.create();
task2.create();
task3.create();
task4.create();
// Lets wake up the threads at different random times
for (i=0; i<10; ++i)
{
sleepTime=rand()%400+100;
printf("Main: Sleeping %dms\n", sleepTime);
ArUtil::sleep(sleepTime);
printf("Main: Waking up a thread\n");
cond.signal();
}
printf("Exiting\n");
// Stop all the threads, which sets their running variable to false
ArThread::stopAll();
// Now that all the threads are marked as not running, wake them up
// so that we can exit the program gracefully.
cond.broadcast();
// Wait for all the threads to exit
ArThread::joinAll();
// Uninit Aria
Aria::uninit();
return(0);
}
|