|  |  |  | @ -7,7 +7,6 @@ | 
		
	
		
			
				|  |  |  |  | #include <sys/socket.h> | 
		
	
		
			
				|  |  |  |  | #include <sys/select.h> | 
		
	
		
			
				|  |  |  |  | #include <netinet/in.h> | 
		
	
		
			
				|  |  |  |  | #include <arpa/inet.h> | 
		
	
		
			
				|  |  |  |  | #include <string.h> | 
		
	
		
			
				|  |  |  |  | #include <fcntl.h> | 
		
	
		
			
				|  |  |  |  | #include <stdio.h> | 
		
	
	
		
			
				
					|  |  |  | @ -82,44 +81,49 @@ int max_fd = -1; | 
		
	
		
			
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				|  |  |  |  | // TODO: Close the socket and return NULL on error
 | 
		
	
		
			
				|  |  |  |  | struct Connection* | 
		
	
		
			
				|  |  |  |  | connection_new(unsigned int source_port, const char* source_ip, unsigned int dest_port, const char* dest_ip) | 
		
	
		
			
				|  |  |  |  | connection_new(uint16_t source_port, uint32_t source_ip, uint16_t dest_port, uint32_t dest_ip) | 
		
	
		
			
				|  |  |  |  | { | 
		
	
		
			
				|  |  |  |  |     struct Connection* conn = malloc(sizeof(struct Connection)); | 
		
	
		
			
				|  |  |  |  |     memset(conn, 0, sizeof(struct Connection)); | 
		
	
		
			
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				|  |  |  |  |     // Request a UDP socket
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				|  |  |  |  |     conn->sockfd = socket(AF_INET, SOCK_DGRAM, 0); | 
		
	
		
			
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				|  |  |  |  |     // Set the source address and port if they are provided
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				|  |  |  |  |     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); | 
		
	
		
			
				|  |  |  |  |        } | 
		
	
		
			
				|  |  |  |  |        conn->local_addr.sin_family = AF_INET; | 
		
	
		
			
				|  |  |  |  |        conn->local_addr.sin_port = htons(source_port); | 
		
	
		
			
				|  |  |  |  |        conn->local_addr.sin_addr.s_addr = source_ip; | 
		
	
		
			
				|  |  |  |  |     } | 
		
	
		
			
				|  |  |  |  |   | 
		
	
		
			
				|  |  |  |  |     // Make the socket non-blocking
 | 
		
	
		
			
				|  |  |  |  |     int flags = fcntl(conn->sockfd, F_GETFL); | 
		
	
		
			
				|  |  |  |  |     fcntl(conn->sockfd, F_SETFL, flags | O_NONBLOCK); | 
		
	
		
			
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				|  |  |  |  |     // Set the address of the drone
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				|  |  |  |  |     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); | 
		
	
		
			
				|  |  |  |  |     conn->remote_addr.sin_addr.s_addr = dest_ip; | 
		
	
		
			
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				|  |  |  |  |     return conn; | 
		
	
		
			
				|  |  |  |  | } | 
		
	
		
			
				|  |  |  |  | 
 | 
		
	
		
			
				|  |  |  |  | enum connection_error | 
		
	
		
			
				|  |  |  |  | connection_connect(struct Connection* conn) { | 
		
	
		
			
				|  |  |  |  | 
 | 
		
	
		
			
				|  |  |  |  |     // Request a UDP socket
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				|  |  |  |  |     conn->sockfd = socket(AF_INET, SOCK_DGRAM, 0); | 
		
	
		
			
				|  |  |  |  | 
 | 
		
	
		
			
				|  |  |  |  |     if(conn->local_addr.sin_addr.s_addr | 
		
	
		
			
				|  |  |  |  |             && bind(conn->sockfd, (struct sockaddr*)&conn->local_addr, sizeof(conn->local_addr)) < 0) | 
		
	
		
			
				|  |  |  |  |         return CONNECTION_LOCAL_BIND; | 
		
	
		
			
				|  |  |  |  |   | 
		
	
		
			
				|  |  |  |  |     // Make the socket non-blocking
 | 
		
	
		
			
				|  |  |  |  |     int flags = fcntl(conn->sockfd, F_GETFL); | 
		
	
		
			
				|  |  |  |  |     fcntl(conn->sockfd, F_SETFL, flags | O_NONBLOCK); | 
		
	
		
			
				|  |  |  |  | 
 | 
		
	
		
			
				|  |  |  |  |     // File descriptors are numbers that count up sequentially,
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				|  |  |  |  |     // so save the last one as the greatest file descriptor.
 | 
		
	
		
			
				|  |  |  |  |     // This is needed for polling the sockets later.
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				|  |  |  |  |     max_fd = conn->sockfd; | 
		
	
		
			
				|  |  |  |  | 
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				|  |  |  |  |     return conn; | 
		
	
		
			
				|  |  |  |  |     return CONNECTION_NO_ERROR; | 
		
	
		
			
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 | 
		
	
		
			
				|  |  |  |  | } | 
		
	
		
			
				|  |  |  |  | 
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				|  |  |  |  | struct Connection* | 
		
	
	
		
			
				
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