libporty - the net package

This package provides low level networking calls for creating sockets and network connections, synchronous dns resolving and polling for socket activity.

The networking and communication model of libporty is simple: sockets are all equivalent and any stream I/O is a socket (see net_async package for more details on how stdio or background processes are converted to sockets). The user may create multiple sockets and a poll call is provided and to wait for activity on one or more sockets. The user application is single threaded asynchronous normally.

Sockets are of type P_net_socket. The caller should not rely on this type to be an integer. A macro P_NET_INVALID_SOCKET is defined; if a socket is == P_NET_INVALID_SOCKET, the socket is invalid (or unused).

Before using the network layer, the application must call P_net_init(). Before exiting, P_net_uninit() shall be called.

libporty/net/network.h

API for the core functionality is implemented in network.h (and in turn in os_dep.h).

call	level	summary
P_net_init	low	initialize network layer
P_net_uninit	low	uninitialize network layer
P_socket	(internal)	create a new socket - note: the application should not use this call directly.
P_net_close	low	close a socket
P_poll	low	poll for activity on a set of sockets
P_net_set_nonblocking	low	set an existing socket non-blocking
P_net_set_blocking	low	set an existing socket blocking
P_net_enable_broadcast	low	enable broadcast messages if the underlying protocol allows (for example on UDP)
P_net_shutdown	low	close a full-duplex socket in one or both directions

The following enum constants are used with some of the calls:

enum	level	summary
P_net_err	low	error code (typically used as return value)
P_net_nonblock_t	low	controls whether sockets operations should be non-blocking, for some of the calls
P_net_broadcast_t	low	controls whether sockets shold allow broadcasting

libporty/net/local.h

Libporty components often communicate with eachother over local sockets. This component can create a local socket pair, which is an anonymous socket on UNIX and a local network (usully TCP) connection on platforms that do not support that.

call	level	summary
P_net_local_socket	low	create a new local socket pair

libporty/net/dns4.h

Synchronous (blocking) dns lookups for TCP/IP v4. Terminology: name is a textual hostname; addr is an IP address as text and IP is binary IP address represented as a 32-bit unsigned long int.

call	level	summary
P_dns4_name_to_IP	low	convert hostname to IP address
P_dns4_IP_to_name	low	convert IP address to hostname
P_dns4_get_my_name	low	returns the hostname of the host system
P_dns4_get_my_IP	low	returns the primary IP address of the host system
P_dns4_is_addr	low	checks if a string contains a valid-looking IP address (non-blocking)
P_dns4_IP_to_addr	low	converts an IP to string address (non-blocking)
P_dns4_addr_to_IP	low	converts a string address to IP (non-blocking)

libporty/net/tcp4.h

Simplified (and portable) API for TCP/IPv4. The basic features of listening for incoming connections, connect to remote host are implemented.

call	level	summary
P_tcp4_connect	low	connect to remote server
P_tcp4_listen	low	listen for incoming connections
P_tcp4_accept	low	accept next pending icoming connection

libporty/net/udp4.h

Simplified (and portable) API for UDP/IPv4.

call	level	summary
P_udp4_connect	low	"connect" to remote server
P_udp4_listen	low	listen for incoming data
P_udp4_recvfrom	low	read packet from a listening socket and also store source IP/port.