10 years, 2 months ago.

Need some help with threads simple application

Need help with threads

Hello,

I am building a small library that creates a thread on its constructor and returns to main thread.

This "worker" thread will just seat on a while (1) reading from a Serial USB (pc) connected to a console. Reads are done via pc.gets(Consolentry,100). Reads not fulfilling a certain format are discarded and the thread goes into an extended Thread::wait to let the main thread make use of the serial console input (potentially).

This worker thread might printf as well to Serial pc for logging.

The main thread, instantiates the class and then goes into a while(1) loop doing other stuff. Potentially reading and writing as well to the console vi Serial pc.

1st Issue: The worker thread will start, change to status Ready and nothing else will happen. Still, worker will never provide a hearbeat telling it is alive. Main never restarts.

2nd Issue: Don't know why, after adding a few printfs here and there, worker will start, will change to state running. Will provide just one heartbeat ( entry into worker) but will never provide exit heartbeat. Then nor main nor worker will do anything again.

Any help appreciated.

Julian

main(){
VarStore Store;
pc.printf("back from constructor never reached....\n");
}

Constructor
VarStore::VarStore()
{
    void *MyThis =(void *)this;
    VarCounter=0;
    pc.printf("launching worker \n");
    Thread t(VarStore::Worker,MyThis,osPriorityNormal,DEFAULT_STACK_SIZE,NULL);
    PrintThreadState( t);
    Thread::wait(100);
    PrintThreadState( t);  /* on issue one this status will never get printed */
}

worker thread

void VarStore::Worker(void const *args)
{
    char ConsoleInput[100];
    int ret;
    VarStore *MyThis=(VarStore *)args;
    pc.printf("inside worker \n");                 /* on issue 2, this will be printed. Nothing else below */
    while (1) {
        if(pc.readable()) {
            pc.printf("inside worker  reading input\n");
            pc.gets(ConsoleInput ,100-1);
            ret=MyThis->Set(ConsoleInput);
            pc.printf("got console input %s \n",ConsoleInput);
            if(ret==ERR) Thread::wait(10000);
        }
                pc.printf("inside worker  waiting input\n");
        Thread::wait(500);
    }
}