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#include <u.h>
#define NOPLAN9DEFINES
#include <libc.h>
#include <ip.h>
#include <sys/socket.h>
#include <netinet/in.h>
/*
* prefix of all v4 addresses
* copied from libip because libc cannot depend on libip
*/
static uchar v4prefix[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0, 0, 0, 0
};
long
udpread(int fd, Udphdr *hdr, void *buf, long n)
{
struct sockaddr_in sin;
socklen_t len;
len = sizeof sin;
n = recvfrom(fd, buf, n, 0, (struct sockaddr*)&sin, &len);
if(len != sizeof sin){
werrstr("recvfrom acting weird");
return -1;
}
if(n < 0)
return -1;
memset(hdr, 0, sizeof *hdr);
memmove(hdr->raddr, v4prefix, IPaddrlen);
*(u32int*)(hdr->raddr+12) = *(u32int*)&sin.sin_addr;
*(u16int*)hdr->rport = *(u16int*)&sin.sin_port;
return n;
}
long
udpwrite(int fd, Udphdr *hdr, void *buf, long n)
{
struct sockaddr_in sin;
memset(&sin, 0, sizeof sin);
sin.sin_family = AF_INET;
*(u32int*)&sin.sin_addr = *(u32int*)(hdr->raddr+12);
*(u16int*)&sin.sin_port = *(u16int*)hdr->rport;
return sendto(fd, buf, n, 0, (struct sockaddr*)&sin, sizeof sin);
}
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