#include <u.h>#include <mingwsock.h>#define NOPLAN9DEFINES#include <libc.h>#include <ip.h> #ifdef __MINGW32__typedef int	socklen_t;#else#include <sys/socket.h>#include <netinet/in.h>#endif longudpread(int fd, Udphdr *hdr, void *buf, long n){	struct sockaddr_in sin;	socklen_t len; 	len = sizeof sin;	if(getsockname(fd, (struct sockaddr*)&sin, &len) < 0)		return -1;	if(len != sizeof sin){		werrstr("getsockname acting weird");		return -1;	}	memset(hdr, 0, sizeof *hdr);	memmove(hdr->laddr, v4prefix, IPaddrlen);	memmove(hdr->laddr+12, &sin.sin_addr, sizeof(u32int));	memmove(hdr->lport, &sin.sin_port, sizeof(u16int)); 	len = sizeof sin;	n = recvfrom(fd, buf, n, 0, (struct sockaddr*)&sin, &len);	if(n < 0)		return -1;	if(len != sizeof sin){		werrstr("recvfrom acting weird");		return -1;	}	memmove(hdr->raddr, v4prefix, IPaddrlen);	memmove(hdr->raddr+12, &sin.sin_addr, sizeof(u32int));	memmove(hdr->rport, &sin.sin_port, sizeof(u16int)); 	return n;} longudpwrite(int fd, Udphdr *hdr, void *buf, long n){	struct sockaddr_in sin; 	memset(&sin, 0, sizeof sin);	sin.sin_family = AF_INET;	memmove(&sin.sin_addr, hdr->raddr+12, 4);	memmove(&sin.sin_port, hdr->rport, 2);	return sendto(fd, buf, n, 0, (struct sockaddr*)&sin, sizeof sin);}