#include #define NOPLAN9DEFINES #include #include #include #include long udpread(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; } long udpwrite(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); }