#include <stdint.h>
#include <stdio.h>
#include <xenctrl.h>
#include <xen/xen.h>
#include <xen/event_channel.h>


static int xce_handle = -1; 
static int src_port = -1;
static int dst_port = -1;
static int xc_handle = -1;

int create_channel(int dom, int remote_dom) {
   
	//open the hypervisor interface
    if (-1 != (xc_handle=xc_interface_open())) {

    //	printf("\n Accquired HYPERVISOR INTERFACE HANDLE: %d \n", xc_handle);

    } else {
    	return -1;	//HYPERVISOR_INTERFACE_OPEN_FAIL
	}
	
	//allocate a port on the remote domain
    if (-1 != (dst_port = xc_evtchn_alloc_unbound(xc_handle, remote_dom, dom))) {
    	
    //	printf("\n Allocated the DEST port %d \n", dst_port);
	
	} else {
		return -2;	//UNBOUND_PORT_ALLOCATION_FAIL
	}
	
	//create a handle for event channel
    if (-1 != (xce_handle = xc_evtchn_open())) {    
    	
    //	printf("\n Accquired HYPERVISOR INTERFACE EVTCHN HANDLE: %d\n", xce_handle);
	
	} else {
		return -3;	//EVENT_CHANN    //create the event channelEL_OPEN_FAIL
	}
	
    //bind src and dst ports
    if(-1 != (src_port = xc_evtchn_bind_interdomain(xce_handle, remote_dom, dst_port))) {
       
    //	printf("\n Allocated the SRC port %d \n", src_port);
    	 
    } else {
    	return -4;	//BINDING_SRC_DST_PORTS_FAIL
    }
    
    return 0;
}

void close_channel(void){
	
	//close hypervisor interface
	xc_interface_close(xc_handle);

	//close event channel
    xc_evtchn_close(xce_handle);

}

void wait_for_event(long ms){

	sleep(ms);
	
}

int main(void){
    
    int ret, dom, remote_dom;
   
	//initialize domains
	dom=0;
	remote_dom=2;    
	
	//create the event channel
    ret = create_channel(dom, remote_dom);
    
    
    if (0 == ret) {
    	printf("\n Event Channel established successfully \n");
    } else {
    	return -1;	//EVENT_CHANNEL_CREATION_FAILED
    }
    
	//wait 20 seconds for an event to occur in DomU
    wait_for_event(20);
    
    //close the opened interfaces
	close_channel();    
       
    return 0;
   
}