01 ws ipc

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Robin Müller 2022-10-05 11:03:55 +02:00
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@ -54,6 +54,7 @@ It is recommended to have a basic understanding of C++ basics and object-oriente
in general before doing this workshop. There are various books and online resources available to
learn this.
All tasks are done in the `main.cpp` of this project and are located in subfolders.
In general, it is recommended to start with the `ws-tasks` workshop and then move to the
`ws-objects` workshop.

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@ -0,0 +1,36 @@
#include <iostream>
#include <thread>
#include <mutex>
using namespace std;
std::mutex SHARED_LOCK;
static uint32_t SHARED_COUNTER = 0;
void task0() {
using namespace std::chrono_literals;
while (true) {
SHARED_LOCK.lock();
cout << "Task0: Shared counter after increment" << ++SHARED_COUNTER << endl;
SHARED_LOCK.unlock();
this_thread::sleep_for(1000ms);
}
}
void task1() {
using namespace std::chrono_literals;
while(true) {
{
std::lock_guard lg(SHARED_LOCK);
cout << "Task1: Shared counter after increment" << ++SHARED_COUNTER << endl;
}
this_thread::sleep_for(1000ms);
}
}
int main() {
std::thread t0(task0);
std::thread t1(task1);
t0.join();
t1.join();
}

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@ -1,5 +1,9 @@
# Threads and Tasks
This workshop is split into 4 subtasks which are done in the `main.cpp` of this
project.
## Background Information
A satellite is a complex system which usually has a lot of tasks which need to be done
simulatenously by a dedicated On-Board Computer (OBC). This can include for example:
@ -36,10 +40,12 @@ string every second: "Hello World".
## 2. Changing to the concept of executable objects
The goal of this task is to convert the code from task 1 so the `std::thread` API takes an
executable object to move to a more object oriented task approach. The printout of the thread
should remain the same. The executable objects should be named `MyExecutableObject`. It contains
one function called `periodicOperation` which performs the printout, and a static function which
takes the `MyExecutableObject` itself by reference and executes it in a permanent loop.
executable object by reference to move to a more object oriented task approach.
The printout of the thread should remain the same. The executable objects should be named
`MyExecutableObject`. It contains one function called `periodicOperation` which performs the
printout, and a static function which takes the `MyExecutableObject` itself by reference and
executes it in a permanent loop.
The executable object should be passed into the `std::thread` directly.
@ -59,7 +65,10 @@ The executable object should be passed into the `std::thread` directly.
4. Implement `executeTask`. This function uses the passed object and performs the scheduling
specific part by calling `self.performOperation` in a permanent loop with a delay between
calls. You can hardcode the delay to 1000ms for the first implementation.
5. Add a constructor to `MyExecutableObject` which expects a millisecond delay
5. Change your `std::thread` calls in the main. You can pass the new `executeTask` function
as the executable unit. The second argument should be an instance of the executable object
itself. You might need the `std::reference_wrapper` to pass it as a reference.
6. Add a constructor to `MyExecutableObject` which expects a millisecond delay
as an `uint32_t` and cache it as a member variable. Then use this member
variable in the `executeTask` implementation to make the task frequency configurable via the
constructor (ctor) parameter.