net #

Description

net provides networking functions. It is mostly a wrapper to BSD sockets, so you can listen on a port, connect to remote TCP/UDP services, and communicate with them.

fn addr_from_socket_handle(handle int) Addr

addr_from_socket_handle returns an address, based on the given integer socket handle

fn close(handle int) !

close a socket, given its file descriptor handle. In non-blocking mode, if close() does not succeed immediately, it causes an error to be propagated to TcpSocket.close(), which is not intended. Therefore, select is used just like connect().

fn default_tcp_dialer() Dialer

default_tcp_dialer will give you an instance of Dialer, that is suitable for making new tcp connections.

fn dial_tcp(oaddress string) !&TcpConn

dial_tcp will try to create a new TcpConn to the given address.

fn dial_tcp_with_bind(saddr string, laddr string) !&TcpConn

dial_tcp_with_bind will bind the given local address laddr and dial.

fn dial_udp(raddr string) !&UdpConn

fn error_code() int

fn listen_tcp(family AddrFamily, saddr string, options ListenOptions) !&TcpListener

fn listen_udp(laddr string) !&UdpConn

fn new_ip(port u16, addr [4]u8) Addr

new_ip creates a new Addr from the IPv4 address family, based on the given port and addr

fn new_ip6(port u16, addr [16]u8) Addr

new_ip6 creates a new Addr from the IP6 address family, based on the given port and addr

fn new_tcp_socket(family AddrFamily) !TcpSocket

This is a workaround for issue https://github.com/vlang/v/issues/20858 noline ensure that in -prod mode(CFLAG = -O3 -flto), gcc does not generate wrong instruction sequence

fn peer_addr_from_socket_handle(handle int) !Addr

peer_addr_from_socket_handle retrieves the ip address and port number, given a socket handle

fn resolve_addrs(addr string, family AddrFamily, typ SocketType) ![]Addr

resolve_addrs converts the given addr, family and typ to a list of addresses

fn resolve_addrs_fuzzy(addr string, typ SocketType) ![]Addr

resolve_addrs converts the given addr and typ to a list of addresses

fn resolve_ipaddrs(addr string, family AddrFamily, typ SocketType) ![]Addr

resolve_ipaddrs converts the given addr, family and typ to a list of addresses

fn set_blocking(handle int, state bool) !

set_blocking will change the state of the socket to either blocking, when state is true, or non blocking (false).

fn shutdown(handle int, config ShutdownConfig) int

shutdown shutsdown a socket, given its file descriptor handle. By default it shuts it down in both directions, both for reading and for writing. You can change that using net.shutdown(handle, how: .read) or net.shutdown(handle, how: .write) In non-blocking mode, shutdown() may not succeed immediately, so select is also used to make sure that the function doesn't return an incorrect result.

fn socket_error(potential_code int) !int

fn socket_error_message(potential_code int, s string) !int

fn split_address(addr string) !(string, u16)

split_address splits an address into its host name and its port

fn tcp_socket_from_handle_raw(sockfd int) TcpSocket

tcp_socket_from_handle_raw is similar to tcp_socket_from_handle, but it does not modify any socket options

fn validate_port(port int) !u16

validate_port checks whether a port is valid and returns the port or an error. The valid ports numbers are between 0 and 0xFFFF. For TCP, port number 0 is reserved and cannot be used, while for UDP, the source port is optional and a value of zero means no port. See also https://en.wikipedia.org/wiki/Port_%28computer_networking%29 .

fn wrap_error(error_code int) !

interface Connection {
	addr() !Addr
	peer_addr() !Addr
mut:
	read(mut []u8) !int
	write([]u8) !int
	close() !
}

Connection provides a generic SOCK_STREAM style interface that protocols can use as a base connection object to support TCP, UNIX Domain Sockets and various proxying solutions.

interface Dialer {
	dial(address string) !Connection
}

Dialer is an abstract dialer interface for producing connections to adresses.

fn (mut s TcpSocket) set_option_bool(opt SocketOption, value bool) !

fn (mut s TcpSocket) set_option_int(opt SocketOption, value int) !

fn (mut s TcpSocket) set_dualstack(on bool) !

fn (mut s TcpSocket) bind(addr string) !

bind a local rddress for TcpSocket

fn (mut s UdpSocket) set_option_bool(opt SocketOption, value bool) !

fn (mut s UdpSocket) set_dualstack(on bool) !

enum AddrFamily {
	unix   = C.AF_UNIX
	ip     = C.AF_INET
	ip6    = C.AF_INET6
	unspec = C.AF_UNSPEC
}

AddrFamily are the available address families

enum ShutdownDirection {
	read
	write
	read_and_write
}

ShutdownDirection is used by net.shutdown, for specifying the direction for which the communication will be cut.

enum SocketOption {
	// TODO: SO_ACCEPT_CONN is not here because windows doesn't support it
	// and there is no easy way to define it
	broadcast        = C.SO_BROADCAST
	debug            = C.SO_DEBUG
	dont_route       = C.SO_DONTROUTE
	error            = C.SO_ERROR
	keep_alive       = C.SO_KEEPALIVE
	linger           = C.SO_LINGER
	oob_inline       = C.SO_OOBINLINE
	reuse_addr       = C.SO_REUSEADDR
	receive_buf_size = C.SO_RCVBUF
	receive_low_size = C.SO_RCVLOWAT
	receive_timeout  = C.SO_RCVTIMEO
	send_buf_size    = C.SO_SNDBUF
	send_low_size    = C.SO_SNDLOWAT
	send_timeout     = C.SO_SNDTIMEO
	socket_type      = C.SO_TYPE
	ipv6_only        = C.IPV6_V6ONLY
	ip_proto_ipv6    = C.IPPROTO_IPV6
	// reuse_port       = C.SO_REUSEPORT // TODO make it work in windows
	// tcp_fastopen     = C.TCP_FASTOPEN // TODO make it work in windows
	// tcp_quickack     = C.TCP_QUICKACK // TODO make it work in os != linux
	// tcp_defer_accept = C.TCP_DEFER_ACCEPT // TODO make it work in windows
}

enum SocketType {
	udp       = C.SOCK_DGRAM
	tcp       = C.SOCK_STREAM
	seqpacket = C.SOCK_SEQPACKET
}

SocketType are the available sockets

struct Addr {
pub:
	f    u16
	addr AddrData
}

fn (a Addr) family() AddrFamily

family returns the family/kind of the given address a

fn (a Addr) len() u32

len returns the length in bytes of the address a, depending on its family

fn (a Addr) port() !u16

port returns the ip or ip6 port of the given address a

fn (a Addr) str() string

str returns a string representation of the address a

struct C.addrinfo {
mut:
	ai_family    int
	ai_socktype  int
	ai_flags     int
	ai_protocol  int
	ai_addrlen   int
	ai_addr      voidptr
	ai_canonname voidptr
	ai_next      voidptr
}

struct C.fd_set {}

struct C.sockaddr_in {
mut:
	sin_family u16
	sin_port   u16
	sin_addr   u32
}

struct C.sockaddr_in6 {
mut:
	sin6_family u16
	sin6_port   u16
	sin6_addr   [4]u32
}

struct C.sockaddr_un {
mut:
	sun_family u16
	sun_path   [max_unix_path]char
}

struct Ip {
	port u16
	addr [4]u8
	// Pad to size so that socket functions
	// dont complain to us (see  in.h and bind())
	// TODO(emily): I would really like to use
	// some constant calculations here
	// so that this doesnt have to be hardcoded
	sin_pad [8]u8
}

fn (a Ip) str() string

str returns a string representation of a

struct Ip6 {
	port      u16
	flow_info u32
	addr      [16]u8
	scope_id  u32
}

fn (a Ip6) str() string

str returns a string representation of a

struct ListenOptions {
pub:
	dualstack bool = true
	backlog   int  = 128
}

struct ShutdownConfig {
pub:
	how ShutdownDirection = .read_and_write
}

struct Socket {
pub:
	handle int
}

fn (s &Socket) address() !Addr

address gets the address of a socket

struct TCPDialer {}

TCPDialer is a concrete instance of the Dialer interface, for creating tcp connections.

fn (t TCPDialer) dial(address string) !Connection

dial will try to create a new abstract connection to the given address. It will return an error, if that is not possible.

struct TcpConn {
pub mut:
	sock           TcpSocket
	handle         int
	write_deadline time.Time
	read_deadline  time.Time
	read_timeout   time.Duration
	write_timeout  time.Duration
	is_blocking    bool = true
}

fn (c &TcpConn) addr() !Addr

fn (mut c TcpConn) close() !

close closes the tcp connection

fn (mut con TcpConn) get_blocking() bool

get_blocking returns whether the connection is in a blocking state, that is calls to .read_line, C.recv etc will block till there is new data arrived, instead of returning immediately.

fn (c &TcpConn) peer_addr() !Addr

peer_addr retrieves the ip address and port number used by the peer

fn (c &TcpConn) peer_ip() !string

peer_ip retrieves the ip address used by the peer, and returns it as a string

fn (c TcpConn) read(mut buf []u8) !int

read reads data from the tcp connection into the mutable buffer buf. The number of bytes read is limited to the length of the buffer buf.len. The returned value is the number of read bytes (between 0 and buf.len).

fn (mut c TcpConn) read_deadline() !time.Time

fn (mut con TcpConn) read_line() string

read_line is a simple, non customizable, blocking line reader. It will return a line, ending with LF, or just '', on EOF.

Note: if you want more control over the buffer, please use a buffered IO reader instead: io.new_buffered_reader({reader: io.make_reader(con)})

fn (mut con TcpConn) read_line_max(max_line_len int) string

read_line_max is a simple, non customizable, blocking line reader. It will return a line, ending with LF, '' on EOF. It stops reading, when the result line length exceeds max_line_len.

fn (c TcpConn) read_ptr(buf_ptr &u8, len int) !int

read_ptr reads data from the tcp connection to the given buffer. It reads at most len bytes. It returns the number of actually read bytes, which can vary between 0 to len.

fn (c &TcpConn) read_timeout() time.Duration

fn (mut con TcpConn) set_blocking(state bool) !

set_blocking will change the state of the connection to either blocking, when state is true, or non blocking (false). The default for net tcp connections is the blocking mode. Calling .read_line will set the connection to blocking mode. In general, changing the blocking mode after a successful connection may cause unexpected surprises, so this function is not recommended to be called anywhere but for this file.

fn (mut c TcpConn) set_read_deadline(deadline time.Time)

fn (mut c TcpConn) set_read_timeout(t time.Duration)

fn (mut c TcpConn) set_sock() !

set_sock initialises the c.sock field. It should be called after .accept_only()!.

Note: just use .accept()!. In most cases it is simpler, and calls .set_sock()! for you.

fn (mut c TcpConn) set_write_deadline(deadline time.Time)

fn (mut c TcpConn) set_write_timeout(t time.Duration)

fn (c TcpConn) str() string

fn (c TcpConn) wait_for_read() !

fn (mut c TcpConn) wait_for_write() !

fn (mut c TcpConn) write(bytes []u8) !int

write blocks and attempts to write all data

fn (mut c TcpConn) write_deadline() !time.Time

fn (mut c TcpConn) write_ptr(b &u8, len int) !int

write_ptr blocks and attempts to write all data

fn (mut c TcpConn) write_string(s string) !int

write_string blocks and attempts to write all data

fn (c &TcpConn) write_timeout() time.Duration

struct TcpListener {
pub mut:
	sock            TcpSocket
	accept_timeout  time.Duration
	accept_deadline time.Time
	is_blocking     bool = true
}

fn (mut l TcpListener) accept() !&TcpConn

accept a tcp connection from an external source to the listener l.

fn (mut l TcpListener) accept_only() !&TcpConn

accept_only accepts a tcp connection from an external source to the listener l. Unlike accept, accept_only will not call .set_sock()! on the result, and is thus faster.

Note: you need to call .set_sock()! manually, before using theconnection after calling .accept_only()!, but that does not have to happen in the same thread that called .accept_only()!. The intention of this API, is to have a more efficient way to accept connections, that are later processed by a thread pool, while the main thread remains active, so that it can accept other connections. See also vlib/vweb/vweb.v .

If you do not need that, just call .accept()! instead, which will call .set_sock()! for you.

fn (c &TcpListener) accept_deadline() !time.Time

fn (mut c TcpListener) set_accept_deadline(deadline time.Time)

fn (c &TcpListener) accept_timeout() time.Duration

fn (mut c TcpListener) set_accept_timeout(t time.Duration)

fn (mut c TcpListener) wait_for_accept() !

fn (mut c TcpListener) close() !

fn (c &TcpListener) addr() !Addr

struct UdpConn {
pub mut:
	sock UdpSocket
mut:
	write_deadline time.Time
	read_deadline  time.Time
	read_timeout   time.Duration
	write_timeout  time.Duration
}

fn (mut c UdpConn) write_ptr(b &u8, len int) !int

sock := UdpSocket{ handle: sbase.handle l: local r: resolve_wrapper(raddr) } }

fn (mut c UdpConn) write(buf []u8) !int

fn (mut c UdpConn) write_string(s string) !int

fn (mut c UdpConn) write_to_ptr(addr Addr, b &u8, len int) !int

fn (mut c UdpConn) write_to(addr Addr, buf []u8) !int

write_to blocks and writes the buf to the remote addr specified

fn (mut c UdpConn) write_to_string(addr Addr, s string) !int

write_to_string blocks and writes the buf to the remote addr specified

fn (mut c UdpConn) read(mut buf []u8) !(int, Addr)

read reads from the socket into buf up to buf.len returning the number of bytes read

fn (c &UdpConn) read_deadline() !time.Time

fn (mut c UdpConn) set_read_deadline(deadline time.Time)

fn (c &UdpConn) write_deadline() !time.Time

fn (mut c UdpConn) set_write_deadline(deadline time.Time)

fn (c &UdpConn) read_timeout() time.Duration

fn (mut c UdpConn) set_read_timeout(t time.Duration)

fn (c &UdpConn) write_timeout() time.Duration

fn (mut c UdpConn) set_write_timeout(t time.Duration)

fn (mut c UdpConn) wait_for_read() !

fn (mut c UdpConn) wait_for_write() !

fn (c &UdpConn) str() string

fn (mut c UdpConn) close() !

struct Unix {
	path [max_unix_path]u8
}