The source code of algorithm Broadcast with ACK

/*******************************************************************
    brdcast_ack.c: Source code of algorithm Broadcast with ACK 

    Design: 3 states {SLEEPING, WAITING, DONE} and 
	    2 messages {BRD, ACK}
    Network topology: connected graph with only one initiator
 ******************************************************************/
typedef struct {
  int parent;
  LIST ack;
}REGISTERS;

REGISTERS *REG;

reg_alloc() {
  REG = (REGISTERS*)malloc(processes*sizeof(REGISTERS));
}

init() {
  int i;

  for( i=0; i<processes; i++) {
    REG[i].parent = -1;
    init_list(REG[i].ack);
  }
}

sleeping_brd() {
  MESSAGE *mess;
  int i;

  if( PCB[me].adjacents == 1) {
    mess = create_message();
    mess->kind = ACK;
    send_to( mess, CURMESS->port);
    new_state = DONE;
  }
  else {
    REG[me].parent = CURMESS->port;
    for( i=0; i<PCB[me].adjacents; i++) {
      if( i != REG[me].parent) {
        insert_list( i, REG[me].ack);
        mess = create_message();
        mess->kind = BRD;
        send_to( mess, i);
      }
    }
    new_state = WAITING;
  }
}

waiting_brd() { /* the same for done_brd()*/
  MESSAGE *mess;

  mess = create_message();
  mess->kind = ACK;
  send_to( mess, CURMESS->port);
}

waiting_ack() {
  MESSAGE *mess;

  delete_list( CURMESS->port, REG[me].ack);
  if( empty_list( REG[me].ack) == TRUE) {
    if( REG[me].parent == -1) { /*initiator*/
      new_state = DONE;
      simul_end();
      return;
    }
    else { /*send ACK to its parent */
      mess = create_message();
      mess->kind = ACK;
      send_to( mess, REG[me].parent);
      new_state = DONE;
    }
  }
}

start() {
  MESSAGE *mess;
  int i;

  if( PCB[me].adjacents == 0) {
    simul_end();
    return;
  }
  for( i=0; i<PCB[me].adjacents; i++) {
    insert_list( i, REG[me].ack);
    mess = create_message();
    mess->kind = BRD;
    send_to( mess, i);
  }
  new_state = WAITING;
}