#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <string.h>

using namespace std;

// to pass multiple arguments
typedef struct str_thdata
{
  int thread_no;
  char message[100];
} thdata;

// Thread functions are member functions of this class
class print_message {
 public:
  print_message () {}
  ~print_message () {}

  void *print_message_function1 ( void *ptr )
  {
    thdata *data;
    data = (thdata *) ptr;  // type cast to a pointer to thdata

    int i;
    for (i=0;i<10;i++) {
      printf("Thread %d says %s \n", data->thread_no, data->message);
    }
    pthread_exit(0);
  }

  void *print_message_function2 ( void *ptr )
  {
    thdata *data;
    data = (thdata *) ptr;  // type cast to a pointer to thdata

    int i;
    for (i=0;i<10;i++) {
      printf("Thread %d says %s \n", data->thread_no, data->message);
    }
    pthread_exit(0);
  }
};

// This is a helper class for thread1 function
class thread_launcher1 {
 public:
 thread_launcher1(print_message *obj, void *arg) :
  p_obj(obj), p_arg(arg) {}
  void *launch () { p_obj->print_message_function1(p_arg); }
  print_message *p_obj;
  void *p_arg;
};

// This is a helper class for thread2 function
class thread_launcher2 {
 public:
 thread_launcher2(print_message *obj, void *arg) :
  p_obj(obj), p_arg(arg) {}
  void *launch () { p_obj->print_message_function2(p_arg); }
  print_message *p_obj;
  void *p_arg;
};

// This is a helper function for thread1 function
void *launch_member_function1(void *obj) {
  thread_launcher1 *mylauncher = reinterpret_cast<thread_launcher1 *> (obj);
  mylauncher->launch();
}

// This is a helper function for thread2 function
void *launch_member_function2(void *obj) {
  thread_launcher2 *mylauncher = reinterpret_cast<thread_launcher2 *> (obj);
  mylauncher->launch();
}

int main()
{
  pthread_t thread1, thread2;
  thdata data1, data2;

  // initialize data to pass to thread 1
  data1.thread_no = 1;
  strcpy(data1.message, "Hello");

  // initialize data to pass to thread 2
  data2.thread_no = 2;
  strcpy(data2.message, "World");

  // a class that has thread functions as member functions
  print_message thread_func;

  // helper classes to call thread functions
  thread_launcher1 launcher1 (&thread_func, (void *) &data1);
  thread_launcher2 launcher2 (&thread_func, (void *) &data2);

  // create threads 1 and 2
  pthread_create (&thread1, NULL, launch_member_function1, (void *) &launcher1);
  pthread_create (&thread2, NULL, launch_member_function2, (void *) &launcher2);

  pthread_join(thread1, NULL);
  pthread_join(thread2, NULL);

  exit(0);
}