#include<pcap.h>
#include<stdio.h>
#include "pcapext.h"


void javacap_init(char* device, bpf_u_int32 bufferSize) {
	(&javacap_d0)->pd=NULL;
	(&javacap_d0)->snaplen=bufferSize;
	(&javacap_d0)->datalink=-1;
	(&javacap_d0)->error=0;
	(&javacap_d0)->device=device;
	(&javacap_d0)->packet=NULL; 
}

void javacap_open(char* dev,int bufferSize) {
	if(dev!=NULL)
		if(*dev!=0)
			javacap_init(dev,bufferSize);
	if((&javacap_d0)->device==NULL) { 
		if( ((&javacap_d0)->device=pcap_lookupdev((&javacap_d0)->errbuf)) ==NULL ){
			(&javacap_d0)->error=ERR_NO_DEV;
			return;	
		}
	}
	if(((&javacap_d0)->pd=pcap_open_live((&javacap_d0)->device,(&javacap_d0)->snaplen,1,500,(&javacap_d0)->errbuf))==NULL){
		(&javacap_d0)->error=ERR_UNABLE_TO_OPEN;
		return; 				
	}
	if(((&javacap_d0)->datalink=pcap_datalink((&javacap_d0)->pd))<0){
		(&javacap_d0)->error=ERR_DATALINK;
		sprintf((&javacap_d0)->errbuf,"%s",pcap_geterr((&javacap_d0)->pd));
		return; 				
	}
}

void javacap_close() {
        pcap_close((&javacap_d0)->pd);
}

char* javacap_read() {
	(&javacap_d0)->packet=(char*) pcap_next((&javacap_d0)->pd,&(&javacap_d0)->hdr);
	return javacap_d0.packet;
}

int javacap_setfilter(char* buf, bpf_u_int32 mask) {
        struct bpf_program fp;
	int optimize = 1;
	int retv = -1;
	
        retv = pcap_compile((&javacap_d0)->pd, &fp, buf, optimize, mask);
        if (retv == 0) {
                pcap_setfilter((&javacap_d0)->pd, &fp);
        }
        return retv;
}

int javacap_getReceivedPackets() {
	struct pcap_stat stat;
	if (pcap_stats((&javacap_d0)->pd, &stat) < 0)
	        return -1;
	else
	        return stat.ps_recv;
}

int javacap_getDroppedPackets() {
	struct pcap_stat stat;
	if (pcap_stats((&javacap_d0)->pd, &stat) < 0)
	        return -1;
	else
	        return stat.ps_drop;
}