#pragma once #include "message.h" #include "client.h" #include "crc.h" #include #include #include #include #include #include #include #include struct Connection { int sockfd; socklen_t addrlen; struct sockaddr_in remote_addr; }; inline static struct Connection* connection_new(unsigned int source_port, const char* source_ip, unsigned int dest_port, const char* dest_ip) { struct Connection* conn = malloc(sizeof(struct Connection)); memset(conn, 0, sizeof(struct Connection)); // Request a UDP socket conn->sockfd = socket(AF_INET, SOCK_DGRAM, 0); if(source_port && source_ip) { struct sockaddr_in loc_addr; loc_addr.sin_family = AF_INET; loc_addr.sin_port = htons(source_port); loc_addr.sin_addr.s_addr = inet_addr(source_ip); if(bind(conn->sockfd, (struct sockaddr*)&loc_addr, sizeof(loc_addr)) < 0) { perror("unable to bind local port"); exit(EXIT_FAILURE); } } // Make the socket non-blocking int flags = fcntl(conn->sockfd, F_GETFL); fcntl(conn->sockfd, F_SETFL, flags | O_NONBLOCK); // Set the address of the drone memset(&conn->remote_addr, 0, sizeof(conn->remote_addr)); conn->addrlen = sizeof(conn->remote_addr); conn->remote_addr.sin_family = AF_INET; conn->remote_addr.sin_port = htons(dest_port); conn->remote_addr.sin_addr.s_addr = inet_addr(dest_ip); return conn; } inline static void connection_set_remote(struct Connection* conn, unsigned int dest_port, const char* dest_ip) { // Set the address of the drone conn->addrlen = sizeof(conn->remote_addr); conn->remote_addr.sin_family = AF_INET; conn->remote_addr.sin_port = htons(dest_port); conn->remote_addr.sin_addr.s_addr = inet_addr(dest_ip); } static inline void req_finalize(struct Client* client, uint8_t cmdset, uint8_t cmdid, size_t length, union Request* req) { req->header.preamble = 0x55; req->header.length_l = length & 0xFF; req->header.length_h = ((length >> 8) & 0x3) | 4; req->header.crc = crc8(req, 3); req->header.seq_id = client->seq++; req->header.sender = client->hostbyte; // TODO: Figure out what this is supposed to be req->header.receiver = host2byte(DEFAULT_CLIENT_HOST, DEFAULT_ROBOT_INDEX); req->header.ack_needed = true; req->header.cmdset = cmdset; req->header.cmdid = cmdid; struct Footer* footer = (void*)req + length - sizeof(struct Footer); uint16_t crc = crc16(req, length - sizeof(struct Footer)); footer->crc = crc; } inline static void req_send(struct Connection* conn, union Request* req, size_t length) { sendto(conn->sockfd, req, length, 0, (struct sockaddr*)&conn->remote_addr, conn->addrlen); }