COSC6490A

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How do you implement a bounded FIFO buffer in C-Linda? Assume the buffer contains integers (to make life a little easier). There are a number of producers and a number of consumer. Assume that the functions consume and produce have already been defined. Now consider the functions consumer and producer.

void consumer() 
{
   int data;
   while (1) 
   {
      data = get();
      consume(data);
   }
}
 
void producer() 
{
   int data;
   while (1) 
   {
      data = produce();
      put(data);
   }
}

A single consumer and producer can be created as follows.

void real_main() 
{
   eval("consumer", consumer());
   eval("producer", producer());
}

How can the above be extended to create multiple consumers and producers?

It remains to define the functions get and put.

int get()
{
   int data;
 
 
 
   return data;
}
 
void put(int data)
{
 
}

How should get and put be completed?

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A try for comment:

void down_mutex()
{
  in("mutex", 1);
  out("mutex", 0);
}
 
void up_mutex()
{
  in("mutex", 0);
  out("mutex", 1);
}
 
int get()
{
  int i, data;
  in("full");
  down_mutex();
  rd("size",?i);
  in("head",?j);
  in("buffer",j,?data);
  j=(j+1)%i;
  out("head",j);
  up_mutex();
  out("empty")
  return data;
}
 
void put(int data)
{
  int i,j;
  in("empty");
  down_mutex();
  rd("size",?i);
  in("tail",?j)
  j=(j+1)%i;
  out("tail",j);
  out("buffer",j,?data);
  up_mutex();
  out("full");
  return;
}
 
void consumer()
{
  int data;
  while (1)
  {
    data = get();
    consume(data);
  }
}
 
void producer()
{
  int data;
  while (1)
  {
    data = produce();
    put(data);
  }
}
void real_main()
{
  #define Len 10
  #define Run 5
  for (int i =0 ; i<Len; i++)
    out("empty");
  out("head",1);
  out("tail", 1);
  out("size",len);
  out("mutex",1);
 
  for (int i =0 ; i<5; i++){
    eval("consumer", consumer());
    eval("producer", producer());
}