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-rw-r--r--ext/socket/lib/socket.rb1356
1 files changed, 1356 insertions, 0 deletions
diff --git a/ext/socket/lib/socket.rb b/ext/socket/lib/socket.rb
new file mode 100644
index 0000000000..18f79b3f08
--- /dev/null
+++ b/ext/socket/lib/socket.rb
@@ -0,0 +1,1356 @@
+# frozen_string_literal: true
+
+require 'socket.so'
+require 'io/wait'
+
+class Addrinfo
+ # creates an Addrinfo object from the arguments.
+ #
+ # The arguments are interpreted as similar to self.
+ #
+ # Addrinfo.tcp("0.0.0.0", 4649).family_addrinfo("www.ruby-lang.org", 80)
+ # #=> #<Addrinfo: 221.186.184.68:80 TCP (www.ruby-lang.org:80)>
+ #
+ # Addrinfo.unix("/tmp/sock").family_addrinfo("/tmp/sock2")
+ # #=> #<Addrinfo: /tmp/sock2 SOCK_STREAM>
+ #
+ def family_addrinfo(*args)
+ if args.empty?
+ raise ArgumentError, "no address specified"
+ elsif Addrinfo === args.first
+ raise ArgumentError, "too many arguments" if args.length != 1
+ addrinfo = args.first
+ if (self.pfamily != addrinfo.pfamily) ||
+ (self.socktype != addrinfo.socktype)
+ raise ArgumentError, "Addrinfo type mismatch"
+ end
+ addrinfo
+ elsif self.ip?
+ raise ArgumentError, "IP address needs host and port but #{args.length} arguments given" if args.length != 2
+ host, port = args
+ Addrinfo.getaddrinfo(host, port, self.pfamily, self.socktype, self.protocol)[0]
+ elsif self.unix?
+ raise ArgumentError, "UNIX socket needs single path argument but #{args.length} arguments given" if args.length != 1
+ path, = args
+ Addrinfo.unix(path)
+ else
+ raise ArgumentError, "unexpected family"
+ end
+ end
+
+ # creates a new Socket connected to the address of +local_addrinfo+.
+ #
+ # If _local_addrinfo_ is nil, the address of the socket is not bound.
+ #
+ # The _timeout_ specify the seconds for timeout.
+ # Errno::ETIMEDOUT is raised when timeout occur.
+ #
+ # If a block is given the created socket is yielded for each address.
+ #
+ def connect_internal(local_addrinfo, timeout=nil) # :yields: socket
+ sock = Socket.new(self.pfamily, self.socktype, self.protocol)
+ begin
+ sock.ipv6only! if self.ipv6?
+ sock.bind local_addrinfo if local_addrinfo
+ if timeout
+ case sock.connect_nonblock(self, exception: false)
+ when 0 # success or EISCONN, other errors raise
+ break
+ when :wait_writable
+ sock.wait_writable(timeout) or
+ raise Errno::ETIMEDOUT, 'user specified timeout'
+ end while true
+ else
+ sock.connect(self)
+ end
+ rescue Exception
+ sock.close
+ raise
+ end
+ if block_given?
+ begin
+ yield sock
+ ensure
+ sock.close
+ end
+ else
+ sock
+ end
+ end
+ private :connect_internal
+
+ # :call-seq:
+ # addrinfo.connect_from([local_addr_args], [opts]) {|socket| ... }
+ # addrinfo.connect_from([local_addr_args], [opts])
+ #
+ # creates a socket connected to the address of self.
+ #
+ # If one or more arguments given as _local_addr_args_,
+ # it is used as the local address of the socket.
+ # _local_addr_args_ is given for family_addrinfo to obtain actual address.
+ #
+ # If _local_addr_args_ is not given, the local address of the socket is not bound.
+ #
+ # The optional last argument _opts_ is options represented by a hash.
+ # _opts_ may have following options:
+ #
+ # [:timeout] specify the timeout in seconds.
+ #
+ # If a block is given, it is called with the socket and the value of the block is returned.
+ # The socket is returned otherwise.
+ #
+ # Addrinfo.tcp("www.ruby-lang.org", 80).connect_from("0.0.0.0", 4649) {|s|
+ # s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
+ # puts s.read
+ # }
+ #
+ # # Addrinfo object can be taken for the argument.
+ # Addrinfo.tcp("www.ruby-lang.org", 80).connect_from(Addrinfo.tcp("0.0.0.0", 4649)) {|s|
+ # s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
+ # puts s.read
+ # }
+ #
+ def connect_from(*args, timeout: nil, &block)
+ connect_internal(family_addrinfo(*args), timeout, &block)
+ end
+
+ # :call-seq:
+ # addrinfo.connect([opts]) {|socket| ... }
+ # addrinfo.connect([opts])
+ #
+ # creates a socket connected to the address of self.
+ #
+ # The optional argument _opts_ is options represented by a hash.
+ # _opts_ may have following options:
+ #
+ # [:timeout] specify the timeout in seconds.
+ #
+ # If a block is given, it is called with the socket and the value of the block is returned.
+ # The socket is returned otherwise.
+ #
+ # Addrinfo.tcp("www.ruby-lang.org", 80).connect {|s|
+ # s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
+ # puts s.read
+ # }
+ #
+ def connect(timeout: nil, &block)
+ connect_internal(nil, timeout, &block)
+ end
+
+ # :call-seq:
+ # addrinfo.connect_to([remote_addr_args], [opts]) {|socket| ... }
+ # addrinfo.connect_to([remote_addr_args], [opts])
+ #
+ # creates a socket connected to _remote_addr_args_ and bound to self.
+ #
+ # The optional last argument _opts_ is options represented by a hash.
+ # _opts_ may have following options:
+ #
+ # [:timeout] specify the timeout in seconds.
+ #
+ # If a block is given, it is called with the socket and the value of the block is returned.
+ # The socket is returned otherwise.
+ #
+ # Addrinfo.tcp("0.0.0.0", 4649).connect_to("www.ruby-lang.org", 80) {|s|
+ # s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
+ # puts s.read
+ # }
+ #
+ def connect_to(*args, timeout: nil, &block)
+ remote_addrinfo = family_addrinfo(*args)
+ remote_addrinfo.send(:connect_internal, self, timeout, &block)
+ end
+
+ # creates a socket bound to self.
+ #
+ # If a block is given, it is called with the socket and the value of the block is returned.
+ # The socket is returned otherwise.
+ #
+ # Addrinfo.udp("0.0.0.0", 9981).bind {|s|
+ # s.local_address.connect {|s| s.send "hello", 0 }
+ # p s.recv(10) #=> "hello"
+ # }
+ #
+ def bind
+ sock = Socket.new(self.pfamily, self.socktype, self.protocol)
+ begin
+ sock.ipv6only! if self.ipv6?
+ sock.setsockopt(:SOCKET, :REUSEADDR, 1)
+ sock.bind(self)
+ rescue Exception
+ sock.close
+ raise
+ end
+ if block_given?
+ begin
+ yield sock
+ ensure
+ sock.close
+ end
+ else
+ sock
+ end
+ end
+
+ # creates a listening socket bound to self.
+ def listen(backlog=Socket::SOMAXCONN)
+ sock = Socket.new(self.pfamily, self.socktype, self.protocol)
+ begin
+ sock.ipv6only! if self.ipv6?
+ sock.setsockopt(:SOCKET, :REUSEADDR, 1)
+ sock.bind(self)
+ sock.listen(backlog)
+ rescue Exception
+ sock.close
+ raise
+ end
+ if block_given?
+ begin
+ yield sock
+ ensure
+ sock.close
+ end
+ else
+ sock
+ end
+ end
+
+ # iterates over the list of Addrinfo objects obtained by Addrinfo.getaddrinfo.
+ #
+ # Addrinfo.foreach(nil, 80) {|x| p x }
+ # #=> #<Addrinfo: 127.0.0.1:80 TCP (:80)>
+ # # #<Addrinfo: 127.0.0.1:80 UDP (:80)>
+ # # #<Addrinfo: [::1]:80 TCP (:80)>
+ # # #<Addrinfo: [::1]:80 UDP (:80)>
+ #
+ def self.foreach(nodename, service, family=nil, socktype=nil, protocol=nil, flags=nil, &block)
+ Addrinfo.getaddrinfo(nodename, service, family, socktype, protocol, flags).each(&block)
+ end
+end
+
+class BasicSocket < IO
+ # Returns an address of the socket suitable for connect in the local machine.
+ #
+ # This method returns _self_.local_address, except following condition.
+ #
+ # - IPv4 unspecified address (0.0.0.0) is replaced by IPv4 loopback address (127.0.0.1).
+ # - IPv6 unspecified address (::) is replaced by IPv6 loopback address (::1).
+ #
+ # If the local address is not suitable for connect, SocketError is raised.
+ # IPv4 and IPv6 address which port is 0 is not suitable for connect.
+ # Unix domain socket which has no path is not suitable for connect.
+ #
+ # Addrinfo.tcp("0.0.0.0", 0).listen {|serv|
+ # p serv.connect_address #=> #<Addrinfo: 127.0.0.1:53660 TCP>
+ # serv.connect_address.connect {|c|
+ # s, _ = serv.accept
+ # p [c, s] #=> [#<Socket:fd 4>, #<Socket:fd 6>]
+ # }
+ # }
+ #
+ def connect_address
+ addr = local_address
+ afamily = addr.afamily
+ if afamily == Socket::AF_INET
+ raise SocketError, "unbound IPv4 socket" if addr.ip_port == 0
+ if addr.ip_address == "0.0.0.0"
+ addr = Addrinfo.new(["AF_INET", addr.ip_port, nil, "127.0.0.1"], addr.pfamily, addr.socktype, addr.protocol)
+ end
+ elsif defined?(Socket::AF_INET6) && afamily == Socket::AF_INET6
+ raise SocketError, "unbound IPv6 socket" if addr.ip_port == 0
+ if addr.ip_address == "::"
+ addr = Addrinfo.new(["AF_INET6", addr.ip_port, nil, "::1"], addr.pfamily, addr.socktype, addr.protocol)
+ elsif addr.ip_address == "0.0.0.0" # MacOS X 10.4 returns "a.b.c.d" for IPv4-mapped IPv6 address.
+ addr = Addrinfo.new(["AF_INET6", addr.ip_port, nil, "::1"], addr.pfamily, addr.socktype, addr.protocol)
+ elsif addr.ip_address == "::ffff:0.0.0.0" # MacOS X 10.6 returns "::ffff:a.b.c.d" for IPv4-mapped IPv6 address.
+ addr = Addrinfo.new(["AF_INET6", addr.ip_port, nil, "::1"], addr.pfamily, addr.socktype, addr.protocol)
+ end
+ elsif defined?(Socket::AF_UNIX) && afamily == Socket::AF_UNIX
+ raise SocketError, "unbound Unix socket" if addr.unix_path == ""
+ end
+ addr
+ end
+
+ # call-seq:
+ # basicsocket.sendmsg(mesg, flags=0, dest_sockaddr=nil, *controls) => numbytes_sent
+ #
+ # sendmsg sends a message using sendmsg(2) system call in blocking manner.
+ #
+ # _mesg_ is a string to send.
+ #
+ # _flags_ is bitwise OR of MSG_* constants such as Socket::MSG_OOB.
+ #
+ # _dest_sockaddr_ is a destination socket address for connection-less socket.
+ # It should be a sockaddr such as a result of Socket.sockaddr_in.
+ # An Addrinfo object can be used too.
+ #
+ # _controls_ is a list of ancillary data.
+ # The element of _controls_ should be Socket::AncillaryData or
+ # 3-elements array.
+ # The 3-element array should contains cmsg_level, cmsg_type and data.
+ #
+ # The return value, _numbytes_sent_ is an integer which is the number of bytes sent.
+ #
+ # sendmsg can be used to implement send_io as follows:
+ #
+ # # use Socket::AncillaryData.
+ # ancdata = Socket::AncillaryData.int(:UNIX, :SOCKET, :RIGHTS, io.fileno)
+ # sock.sendmsg("a", 0, nil, ancdata)
+ #
+ # # use 3-element array.
+ # ancdata = [:SOCKET, :RIGHTS, [io.fileno].pack("i!")]
+ # sock.sendmsg("\0", 0, nil, ancdata)
+ def sendmsg(mesg, flags = 0, dest_sockaddr = nil, *controls)
+ __sendmsg(mesg, flags, dest_sockaddr, controls)
+ end
+
+ # call-seq:
+ # basicsocket.sendmsg_nonblock(mesg, flags=0, dest_sockaddr=nil, *controls, opts={}) => numbytes_sent
+ #
+ # sendmsg_nonblock sends a message using sendmsg(2) system call in non-blocking manner.
+ #
+ # It is similar to BasicSocket#sendmsg
+ # but the non-blocking flag is set before the system call
+ # and it doesn't retry the system call.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that sendmsg_nonblock should not raise an IO::WaitWritable exception, but
+ # return the symbol +:wait_writable+ instead.
+ def sendmsg_nonblock(mesg, flags = 0, dest_sockaddr = nil, *controls,
+ exception: true)
+ __sendmsg_nonblock(mesg, flags, dest_sockaddr, controls, exception)
+ end
+
+ # call-seq:
+ # basicsocket.recv_nonblock(maxlen [, flags [, buf [, options ]]]) => mesg
+ #
+ # Receives up to _maxlen_ bytes from +socket+ using recvfrom(2) after
+ # O_NONBLOCK is set for the underlying file descriptor.
+ # _flags_ is zero or more of the +MSG_+ options.
+ # The result, _mesg_, is the data received.
+ #
+ # When recvfrom(2) returns 0, Socket#recv_nonblock returns
+ # an empty string as data.
+ # The meaning depends on the socket: EOF on TCP, empty packet on UDP, etc.
+ #
+ # === Parameters
+ # * +maxlen+ - the number of bytes to receive from the socket
+ # * +flags+ - zero or more of the +MSG_+ options
+ # * +buf+ - destination String buffer
+ # * +options+ - keyword hash, supporting `exception: false`
+ #
+ # === Example
+ # serv = TCPServer.new("127.0.0.1", 0)
+ # af, port, host, addr = serv.addr
+ # c = TCPSocket.new(addr, port)
+ # s = serv.accept
+ # c.send "aaa", 0
+ # begin # emulate blocking recv.
+ # p s.recv_nonblock(10) #=> "aaa"
+ # rescue IO::WaitReadable
+ # IO.select([s])
+ # retry
+ # end
+ #
+ # Refer to Socket#recvfrom for the exceptions that may be thrown if the call
+ # to _recv_nonblock_ fails.
+ #
+ # BasicSocket#recv_nonblock may raise any error corresponding to recvfrom(2) failure,
+ # including Errno::EWOULDBLOCK.
+ #
+ # If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN,
+ # it is extended by IO::WaitReadable.
+ # So IO::WaitReadable can be used to rescue the exceptions for retrying recv_nonblock.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that recv_nonblock should not raise an IO::WaitReadable exception, but
+ # return the symbol +:wait_readable+ instead.
+ #
+ # === See
+ # * Socket#recvfrom
+ def recv_nonblock(len, flag = 0, str = nil, exception: true)
+ __recv_nonblock(len, flag, str, exception)
+ end
+
+ # call-seq:
+ # basicsocket.recvmsg(maxmesglen=nil, flags=0, maxcontrollen=nil, opts={}) => [mesg, sender_addrinfo, rflags, *controls]
+ #
+ # recvmsg receives a message using recvmsg(2) system call in blocking manner.
+ #
+ # _maxmesglen_ is the maximum length of mesg to receive.
+ #
+ # _flags_ is bitwise OR of MSG_* constants such as Socket::MSG_PEEK.
+ #
+ # _maxcontrollen_ is the maximum length of controls (ancillary data) to receive.
+ #
+ # _opts_ is option hash.
+ # Currently :scm_rights=>bool is the only option.
+ #
+ # :scm_rights option specifies that application expects SCM_RIGHTS control message.
+ # If the value is nil or false, application don't expects SCM_RIGHTS control message.
+ # In this case, recvmsg closes the passed file descriptors immediately.
+ # This is the default behavior.
+ #
+ # If :scm_rights value is neither nil nor false, application expects SCM_RIGHTS control message.
+ # In this case, recvmsg creates IO objects for each file descriptors for
+ # Socket::AncillaryData#unix_rights method.
+ #
+ # The return value is 4-elements array.
+ #
+ # _mesg_ is a string of the received message.
+ #
+ # _sender_addrinfo_ is a sender socket address for connection-less socket.
+ # It is an Addrinfo object.
+ # For connection-oriented socket such as TCP, sender_addrinfo is platform dependent.
+ #
+ # _rflags_ is a flags on the received message which is bitwise OR of MSG_* constants such as Socket::MSG_TRUNC.
+ # It will be nil if the system uses 4.3BSD style old recvmsg system call.
+ #
+ # _controls_ is ancillary data which is an array of Socket::AncillaryData objects such as:
+ #
+ # #<Socket::AncillaryData: AF_UNIX SOCKET RIGHTS 7>
+ #
+ # _maxmesglen_ and _maxcontrollen_ can be nil.
+ # In that case, the buffer will be grown until the message is not truncated.
+ # Internally, MSG_PEEK is used.
+ # Buffer full and MSG_CTRUNC are checked for truncation.
+ #
+ # recvmsg can be used to implement recv_io as follows:
+ #
+ # mesg, sender_sockaddr, rflags, *controls = sock.recvmsg(:scm_rights=>true)
+ # controls.each {|ancdata|
+ # if ancdata.cmsg_is?(:SOCKET, :RIGHTS)
+ # return ancdata.unix_rights[0]
+ # end
+ # }
+ def recvmsg(dlen = nil, flags = 0, clen = nil, scm_rights: false)
+ __recvmsg(dlen, flags, clen, scm_rights)
+ end
+
+ # call-seq:
+ # basicsocket.recvmsg_nonblock(maxdatalen=nil, flags=0, maxcontrollen=nil, opts={}) => [data, sender_addrinfo, rflags, *controls]
+ #
+ # recvmsg receives a message using recvmsg(2) system call in non-blocking manner.
+ #
+ # It is similar to BasicSocket#recvmsg
+ # but non-blocking flag is set before the system call
+ # and it doesn't retry the system call.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that recvmsg_nonblock should not raise an IO::WaitReadable exception, but
+ # return the symbol +:wait_readable+ instead.
+ def recvmsg_nonblock(dlen = nil, flags = 0, clen = nil,
+ scm_rights: false, exception: true)
+ __recvmsg_nonblock(dlen, flags, clen, scm_rights, exception)
+ end
+
+ # Linux-specific optimizations to avoid fcntl for IO#read_nonblock
+ # and IO#write_nonblock using MSG_DONTWAIT
+ # Do other platforms support MSG_DONTWAIT reliably?
+ if RUBY_PLATFORM =~ /linux/ && Socket.const_defined?(:MSG_DONTWAIT)
+ def read_nonblock(len, str = nil, exception: true) # :nodoc:
+ __read_nonblock(len, str, exception)
+ end
+
+ def write_nonblock(buf, exception: true) # :nodoc:
+ __write_nonblock(buf, exception)
+ end
+ end
+end
+
+class Socket < BasicSocket
+ # enable the socket option IPV6_V6ONLY if IPV6_V6ONLY is available.
+ def ipv6only!
+ if defined? Socket::IPV6_V6ONLY
+ self.setsockopt(:IPV6, :V6ONLY, 1)
+ end
+ end
+
+ # call-seq:
+ # socket.recvfrom_nonblock(maxlen[, flags[, outbuf[, opts]]]) => [mesg, sender_addrinfo]
+ #
+ # Receives up to _maxlen_ bytes from +socket+ using recvfrom(2) after
+ # O_NONBLOCK is set for the underlying file descriptor.
+ # _flags_ is zero or more of the +MSG_+ options.
+ # The first element of the results, _mesg_, is the data received.
+ # The second element, _sender_addrinfo_, contains protocol-specific address
+ # information of the sender.
+ #
+ # When recvfrom(2) returns 0, Socket#recvfrom_nonblock returns
+ # an empty string as data.
+ # The meaning depends on the socket: EOF on TCP, empty packet on UDP, etc.
+ #
+ # === Parameters
+ # * +maxlen+ - the maximum number of bytes to receive from the socket
+ # * +flags+ - zero or more of the +MSG_+ options
+ # * +outbuf+ - destination String buffer
+ # * +opts+ - keyword hash, supporting `exception: false`
+ #
+ # === Example
+ # # In one file, start this first
+ # require 'socket'
+ # include Socket::Constants
+ # socket = Socket.new(AF_INET, SOCK_STREAM, 0)
+ # sockaddr = Socket.sockaddr_in(2200, 'localhost')
+ # socket.bind(sockaddr)
+ # socket.listen(5)
+ # client, client_addrinfo = socket.accept
+ # begin # emulate blocking recvfrom
+ # pair = client.recvfrom_nonblock(20)
+ # rescue IO::WaitReadable
+ # IO.select([client])
+ # retry
+ # end
+ # data = pair[0].chomp
+ # puts "I only received 20 bytes '#{data}'"
+ # sleep 1
+ # socket.close
+ #
+ # # In another file, start this second
+ # require 'socket'
+ # include Socket::Constants
+ # socket = Socket.new(AF_INET, SOCK_STREAM, 0)
+ # sockaddr = Socket.sockaddr_in(2200, 'localhost')
+ # socket.connect(sockaddr)
+ # socket.puts "Watch this get cut short!"
+ # socket.close
+ #
+ # Refer to Socket#recvfrom for the exceptions that may be thrown if the call
+ # to _recvfrom_nonblock_ fails.
+ #
+ # Socket#recvfrom_nonblock may raise any error corresponding to recvfrom(2) failure,
+ # including Errno::EWOULDBLOCK.
+ #
+ # If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN,
+ # it is extended by IO::WaitReadable.
+ # So IO::WaitReadable can be used to rescue the exceptions for retrying
+ # recvfrom_nonblock.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that recvfrom_nonblock should not raise an IO::WaitReadable exception, but
+ # return the symbol +:wait_readable+ instead.
+ #
+ # === See
+ # * Socket#recvfrom
+ def recvfrom_nonblock(len, flag = 0, str = nil, exception: true)
+ __recvfrom_nonblock(len, flag, str, exception)
+ end
+
+ # call-seq:
+ # socket.accept_nonblock([options]) => [client_socket, client_addrinfo]
+ #
+ # Accepts an incoming connection using accept(2) after
+ # O_NONBLOCK is set for the underlying file descriptor.
+ # It returns an array containing the accepted socket
+ # for the incoming connection, _client_socket_,
+ # and an Addrinfo, _client_addrinfo_.
+ #
+ # === Example
+ # # In one script, start this first
+ # require 'socket'
+ # include Socket::Constants
+ # socket = Socket.new(AF_INET, SOCK_STREAM, 0)
+ # sockaddr = Socket.sockaddr_in(2200, 'localhost')
+ # socket.bind(sockaddr)
+ # socket.listen(5)
+ # begin # emulate blocking accept
+ # client_socket, client_addrinfo = socket.accept_nonblock
+ # rescue IO::WaitReadable, Errno::EINTR
+ # IO.select([socket])
+ # retry
+ # end
+ # puts "The client said, '#{client_socket.readline.chomp}'"
+ # client_socket.puts "Hello from script one!"
+ # socket.close
+ #
+ # # In another script, start this second
+ # require 'socket'
+ # include Socket::Constants
+ # socket = Socket.new(AF_INET, SOCK_STREAM, 0)
+ # sockaddr = Socket.sockaddr_in(2200, 'localhost')
+ # socket.connect(sockaddr)
+ # socket.puts "Hello from script 2."
+ # puts "The server said, '#{socket.readline.chomp}'"
+ # socket.close
+ #
+ # Refer to Socket#accept for the exceptions that may be thrown if the call
+ # to _accept_nonblock_ fails.
+ #
+ # Socket#accept_nonblock may raise any error corresponding to accept(2) failure,
+ # including Errno::EWOULDBLOCK.
+ #
+ # If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED or Errno::EPROTO,
+ # it is extended by IO::WaitReadable.
+ # So IO::WaitReadable can be used to rescue the exceptions for retrying accept_nonblock.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that accept_nonblock should not raise an IO::WaitReadable exception, but
+ # return the symbol +:wait_readable+ instead.
+ #
+ # === See
+ # * Socket#accept
+ def accept_nonblock(exception: true)
+ __accept_nonblock(exception)
+ end
+
+ # :call-seq:
+ # Socket.tcp(host, port, local_host=nil, local_port=nil, [opts]) {|socket| ... }
+ # Socket.tcp(host, port, local_host=nil, local_port=nil, [opts])
+ #
+ # creates a new socket object connected to host:port using TCP/IP.
+ #
+ # If local_host:local_port is given,
+ # the socket is bound to it.
+ #
+ # The optional last argument _opts_ is options represented by a hash.
+ # _opts_ may have following options:
+ #
+ # [:connect_timeout] specify the timeout in seconds.
+ #
+ # If a block is given, the block is called with the socket.
+ # The value of the block is returned.
+ # The socket is closed when this method returns.
+ #
+ # If no block is given, the socket is returned.
+ #
+ # Socket.tcp("www.ruby-lang.org", 80) {|sock|
+ # sock.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
+ # sock.close_write
+ # puts sock.read
+ # }
+ #
+ def self.tcp(host, port, local_host = nil, local_port = nil, connect_timeout: nil) # :yield: socket
+ last_error = nil
+ ret = nil
+
+ local_addr_list = nil
+ if local_host != nil || local_port != nil
+ local_addr_list = Addrinfo.getaddrinfo(local_host, local_port, nil, :STREAM, nil)
+ end
+
+ Addrinfo.foreach(host, port, nil, :STREAM) {|ai|
+ if local_addr_list
+ local_addr = local_addr_list.find {|local_ai| local_ai.afamily == ai.afamily }
+ next unless local_addr
+ else
+ local_addr = nil
+ end
+ begin
+ sock = local_addr ?
+ ai.connect_from(local_addr, timeout: connect_timeout) :
+ ai.connect(timeout: connect_timeout)
+ rescue SystemCallError
+ last_error = $!
+ next
+ end
+ ret = sock
+ break
+ }
+ unless ret
+ if last_error
+ raise last_error
+ else
+ raise SocketError, "no appropriate local address"
+ end
+ end
+ if block_given?
+ begin
+ yield ret
+ ensure
+ ret.close
+ end
+ else
+ ret
+ end
+ end
+
+ # :stopdoc:
+ def self.ip_sockets_port0(ai_list, reuseaddr)
+ sockets = []
+ begin
+ sockets.clear
+ port = nil
+ ai_list.each {|ai|
+ begin
+ s = Socket.new(ai.pfamily, ai.socktype, ai.protocol)
+ rescue SystemCallError
+ next
+ end
+ sockets << s
+ s.ipv6only! if ai.ipv6?
+ if reuseaddr
+ s.setsockopt(:SOCKET, :REUSEADDR, 1)
+ end
+ unless port
+ s.bind(ai)
+ port = s.local_address.ip_port
+ else
+ s.bind(ai.family_addrinfo(ai.ip_address, port))
+ end
+ }
+ rescue Errno::EADDRINUSE
+ sockets.each(&:close)
+ retry
+ rescue Exception
+ sockets.each(&:close)
+ raise
+ end
+ sockets
+ end
+ class << self
+ private :ip_sockets_port0
+ end
+
+ def self.tcp_server_sockets_port0(host)
+ ai_list = Addrinfo.getaddrinfo(host, 0, nil, :STREAM, nil, Socket::AI_PASSIVE)
+ sockets = ip_sockets_port0(ai_list, true)
+ begin
+ sockets.each {|s|
+ s.listen(Socket::SOMAXCONN)
+ }
+ rescue Exception
+ sockets.each(&:close)
+ raise
+ end
+ sockets
+ end
+ class << self
+ private :tcp_server_sockets_port0
+ end
+ # :startdoc:
+
+ # creates TCP/IP server sockets for _host_ and _port_.
+ # _host_ is optional.
+ #
+ # If no block given,
+ # it returns an array of listening sockets.
+ #
+ # If a block is given, the block is called with the sockets.
+ # The value of the block is returned.
+ # The socket is closed when this method returns.
+ #
+ # If _port_ is 0, actual port number is chosen dynamically.
+ # However all sockets in the result has same port number.
+ #
+ # # tcp_server_sockets returns two sockets.
+ # sockets = Socket.tcp_server_sockets(1296)
+ # p sockets #=> [#<Socket:fd 3>, #<Socket:fd 4>]
+ #
+ # # The sockets contains IPv6 and IPv4 sockets.
+ # sockets.each {|s| p s.local_address }
+ # #=> #<Addrinfo: [::]:1296 TCP>
+ # # #<Addrinfo: 0.0.0.0:1296 TCP>
+ #
+ # # IPv6 and IPv4 socket has same port number, 53114, even if it is chosen dynamically.
+ # sockets = Socket.tcp_server_sockets(0)
+ # sockets.each {|s| p s.local_address }
+ # #=> #<Addrinfo: [::]:53114 TCP>
+ # # #<Addrinfo: 0.0.0.0:53114 TCP>
+ #
+ # # The block is called with the sockets.
+ # Socket.tcp_server_sockets(0) {|sockets|
+ # p sockets #=> [#<Socket:fd 3>, #<Socket:fd 4>]
+ # }
+ #
+ def self.tcp_server_sockets(host=nil, port)
+ if port == 0
+ sockets = tcp_server_sockets_port0(host)
+ else
+ last_error = nil
+ sockets = []
+ begin
+ Addrinfo.foreach(host, port, nil, :STREAM, nil, Socket::AI_PASSIVE) {|ai|
+ begin
+ s = ai.listen
+ rescue SystemCallError
+ last_error = $!
+ next
+ end
+ sockets << s
+ }
+ if sockets.empty?
+ raise last_error
+ end
+ rescue Exception
+ sockets.each(&:close)
+ raise
+ end
+ end
+ if block_given?
+ begin
+ yield sockets
+ ensure
+ sockets.each(&:close)
+ end
+ else
+ sockets
+ end
+ end
+
+ # yield socket and client address for each a connection accepted via given sockets.
+ #
+ # The arguments are a list of sockets.
+ # The individual argument should be a socket or an array of sockets.
+ #
+ # This method yields the block sequentially.
+ # It means that the next connection is not accepted until the block returns.
+ # So concurrent mechanism, thread for example, should be used to service multiple clients at a time.
+ #
+ def self.accept_loop(*sockets) # :yield: socket, client_addrinfo
+ sockets.flatten!(1)
+ if sockets.empty?
+ raise ArgumentError, "no sockets"
+ end
+ loop {
+ readable, _, _ = IO.select(sockets)
+ readable.each {|r|
+ sock, addr = r.accept_nonblock(exception: false)
+ next if sock == :wait_readable
+ yield sock, addr
+ }
+ }
+ end
+
+ # creates a TCP/IP server on _port_ and calls the block for each connection accepted.
+ # The block is called with a socket and a client_address as an Addrinfo object.
+ #
+ # If _host_ is specified, it is used with _port_ to determine the server addresses.
+ #
+ # The socket is *not* closed when the block returns.
+ # So application should close it explicitly.
+ #
+ # This method calls the block sequentially.
+ # It means that the next connection is not accepted until the block returns.
+ # So concurrent mechanism, thread for example, should be used to service multiple clients at a time.
+ #
+ # Note that Addrinfo.getaddrinfo is used to determine the server socket addresses.
+ # When Addrinfo.getaddrinfo returns two or more addresses,
+ # IPv4 and IPv6 address for example,
+ # all of them are used.
+ # Socket.tcp_server_loop succeeds if one socket can be used at least.
+ #
+ # # Sequential echo server.
+ # # It services only one client at a time.
+ # Socket.tcp_server_loop(16807) {|sock, client_addrinfo|
+ # begin
+ # IO.copy_stream(sock, sock)
+ # ensure
+ # sock.close
+ # end
+ # }
+ #
+ # # Threaded echo server
+ # # It services multiple clients at a time.
+ # # Note that it may accept connections too much.
+ # Socket.tcp_server_loop(16807) {|sock, client_addrinfo|
+ # Thread.new {
+ # begin
+ # IO.copy_stream(sock, sock)
+ # ensure
+ # sock.close
+ # end
+ # }
+ # }
+ #
+ def self.tcp_server_loop(host=nil, port, &b) # :yield: socket, client_addrinfo
+ tcp_server_sockets(host, port) {|sockets|
+ accept_loop(sockets, &b)
+ }
+ end
+
+ # :call-seq:
+ # Socket.udp_server_sockets([host, ] port)
+ #
+ # Creates UDP/IP sockets for a UDP server.
+ #
+ # If no block given, it returns an array of sockets.
+ #
+ # If a block is given, the block is called with the sockets.
+ # The value of the block is returned.
+ # The sockets are closed when this method returns.
+ #
+ # If _port_ is zero, some port is chosen.
+ # But the chosen port is used for the all sockets.
+ #
+ # # UDP/IP echo server
+ # Socket.udp_server_sockets(0) {|sockets|
+ # p sockets.first.local_address.ip_port #=> 32963
+ # Socket.udp_server_loop_on(sockets) {|msg, msg_src|
+ # msg_src.reply msg
+ # }
+ # }
+ #
+ def self.udp_server_sockets(host=nil, port)
+ last_error = nil
+ sockets = []
+
+ ipv6_recvpktinfo = nil
+ if defined? Socket::AncillaryData
+ if defined? Socket::IPV6_RECVPKTINFO # RFC 3542
+ ipv6_recvpktinfo = Socket::IPV6_RECVPKTINFO
+ elsif defined? Socket::IPV6_PKTINFO # RFC 2292
+ ipv6_recvpktinfo = Socket::IPV6_PKTINFO
+ end
+ end
+
+ local_addrs = Socket.ip_address_list
+
+ ip_list = []
+ Addrinfo.foreach(host, port, nil, :DGRAM, nil, Socket::AI_PASSIVE) {|ai|
+ if ai.ipv4? && ai.ip_address == "0.0.0.0"
+ local_addrs.each {|a|
+ next unless a.ipv4?
+ ip_list << Addrinfo.new(a.to_sockaddr, :INET, :DGRAM, 0);
+ }
+ elsif ai.ipv6? && ai.ip_address == "::" && !ipv6_recvpktinfo
+ local_addrs.each {|a|
+ next unless a.ipv6?
+ ip_list << Addrinfo.new(a.to_sockaddr, :INET6, :DGRAM, 0);
+ }
+ else
+ ip_list << ai
+ end
+ }
+ ip_list.uniq!(&:to_sockaddr)
+
+ if port == 0
+ sockets = ip_sockets_port0(ip_list, false)
+ else
+ ip_list.each {|ip|
+ ai = Addrinfo.udp(ip.ip_address, port)
+ begin
+ s = ai.bind
+ rescue SystemCallError
+ last_error = $!
+ next
+ end
+ sockets << s
+ }
+ if sockets.empty?
+ raise last_error
+ end
+ end
+
+ sockets.each {|s|
+ ai = s.local_address
+ if ipv6_recvpktinfo && ai.ipv6? && ai.ip_address == "::"
+ s.setsockopt(:IPV6, ipv6_recvpktinfo, 1)
+ end
+ }
+
+ if block_given?
+ begin
+ yield sockets
+ ensure
+ sockets.each(&:close) if sockets
+ end
+ else
+ sockets
+ end
+ end
+
+ # :call-seq:
+ # Socket.udp_server_recv(sockets) {|msg, msg_src| ... }
+ #
+ # Receive UDP/IP packets from the given _sockets_.
+ # For each packet received, the block is called.
+ #
+ # The block receives _msg_ and _msg_src_.
+ # _msg_ is a string which is the payload of the received packet.
+ # _msg_src_ is a Socket::UDPSource object which is used for reply.
+ #
+ # Socket.udp_server_loop can be implemented using this method as follows.
+ #
+ # udp_server_sockets(host, port) {|sockets|
+ # loop {
+ # readable, _, _ = IO.select(sockets)
+ # udp_server_recv(readable) {|msg, msg_src| ... }
+ # }
+ # }
+ #
+ def self.udp_server_recv(sockets)
+ sockets.each {|r|
+ msg, sender_addrinfo, _, *controls = r.recvmsg_nonblock(exception: false)
+ next if msg == :wait_readable
+ ai = r.local_address
+ if ai.ipv6? and pktinfo = controls.find {|c| c.cmsg_is?(:IPV6, :PKTINFO) }
+ ai = Addrinfo.udp(pktinfo.ipv6_pktinfo_addr.ip_address, ai.ip_port)
+ yield msg, UDPSource.new(sender_addrinfo, ai) {|reply_msg|
+ r.sendmsg reply_msg, 0, sender_addrinfo, pktinfo
+ }
+ else
+ yield msg, UDPSource.new(sender_addrinfo, ai) {|reply_msg|
+ r.send reply_msg, 0, sender_addrinfo
+ }
+ end
+ }
+ end
+
+ # :call-seq:
+ # Socket.udp_server_loop_on(sockets) {|msg, msg_src| ... }
+ #
+ # Run UDP/IP server loop on the given sockets.
+ #
+ # The return value of Socket.udp_server_sockets is appropriate for the argument.
+ #
+ # It calls the block for each message received.
+ #
+ def self.udp_server_loop_on(sockets, &b) # :yield: msg, msg_src
+ loop {
+ readable, _, _ = IO.select(sockets)
+ udp_server_recv(readable, &b)
+ }
+ end
+
+ # :call-seq:
+ # Socket.udp_server_loop(port) {|msg, msg_src| ... }
+ # Socket.udp_server_loop(host, port) {|msg, msg_src| ... }
+ #
+ # creates a UDP/IP server on _port_ and calls the block for each message arrived.
+ # The block is called with the message and its source information.
+ #
+ # This method allocates sockets internally using _port_.
+ # If _host_ is specified, it is used conjunction with _port_ to determine the server addresses.
+ #
+ # The _msg_ is a string.
+ #
+ # The _msg_src_ is a Socket::UDPSource object.
+ # It is used for reply.
+ #
+ # # UDP/IP echo server.
+ # Socket.udp_server_loop(9261) {|msg, msg_src|
+ # msg_src.reply msg
+ # }
+ #
+ def self.udp_server_loop(host=nil, port, &b) # :yield: message, message_source
+ udp_server_sockets(host, port) {|sockets|
+ udp_server_loop_on(sockets, &b)
+ }
+ end
+
+ # UDP/IP address information used by Socket.udp_server_loop.
+ class UDPSource
+ # +remote_address+ is an Addrinfo object.
+ #
+ # +local_address+ is an Addrinfo object.
+ #
+ # +reply_proc+ is a Proc used to send reply back to the source.
+ def initialize(remote_address, local_address, &reply_proc)
+ @remote_address = remote_address
+ @local_address = local_address
+ @reply_proc = reply_proc
+ end
+
+ # Address of the source
+ attr_reader :remote_address
+
+ # Local address
+ attr_reader :local_address
+
+ def inspect # :nodoc:
+ "\#<#{self.class}: #{@remote_address.inspect_sockaddr} to #{@local_address.inspect_sockaddr}>".dup
+ end
+
+ # Sends the String +msg+ to the source
+ def reply(msg)
+ @reply_proc.call msg
+ end
+ end
+
+ # creates a new socket connected to path using UNIX socket socket.
+ #
+ # If a block is given, the block is called with the socket.
+ # The value of the block is returned.
+ # The socket is closed when this method returns.
+ #
+ # If no block is given, the socket is returned.
+ #
+ # # talk to /tmp/sock socket.
+ # Socket.unix("/tmp/sock") {|sock|
+ # t = Thread.new { IO.copy_stream(sock, STDOUT) }
+ # IO.copy_stream(STDIN, sock)
+ # t.join
+ # }
+ #
+ def self.unix(path) # :yield: socket
+ addr = Addrinfo.unix(path)
+ sock = addr.connect
+ if block_given?
+ begin
+ yield sock
+ ensure
+ sock.close
+ end
+ else
+ sock
+ end
+ end
+
+ # creates a UNIX server socket on _path_
+ #
+ # If no block given, it returns a listening socket.
+ #
+ # If a block is given, it is called with the socket and the block value is returned.
+ # When the block exits, the socket is closed and the socket file is removed.
+ #
+ # socket = Socket.unix_server_socket("/tmp/s")
+ # p socket #=> #<Socket:fd 3>
+ # p socket.local_address #=> #<Addrinfo: /tmp/s SOCK_STREAM>
+ #
+ # Socket.unix_server_socket("/tmp/sock") {|s|
+ # p s #=> #<Socket:fd 3>
+ # p s.local_address #=> # #<Addrinfo: /tmp/sock SOCK_STREAM>
+ # }
+ #
+ def self.unix_server_socket(path)
+ unless unix_socket_abstract_name?(path)
+ begin
+ st = File.lstat(path)
+ rescue Errno::ENOENT
+ end
+ if st&.socket? && st.owned?
+ File.unlink path
+ end
+ end
+ s = Addrinfo.unix(path).listen
+ if block_given?
+ begin
+ yield s
+ ensure
+ s.close
+ unless unix_socket_abstract_name?(path)
+ File.unlink path
+ end
+ end
+ else
+ s
+ end
+ end
+
+ class << self
+ private
+
+ def unix_socket_abstract_name?(path)
+ /linux/ =~ RUBY_PLATFORM && /\A(\0|\z)/ =~ path
+ end
+ end
+
+ # creates a UNIX socket server on _path_.
+ # It calls the block for each socket accepted.
+ #
+ # If _host_ is specified, it is used with _port_ to determine the server ports.
+ #
+ # The socket is *not* closed when the block returns.
+ # So application should close it.
+ #
+ # This method deletes the socket file pointed by _path_ at first if
+ # the file is a socket file and it is owned by the user of the application.
+ # This is safe only if the directory of _path_ is not changed by a malicious user.
+ # So don't use /tmp/malicious-users-directory/socket.
+ # Note that /tmp/socket and /tmp/your-private-directory/socket is safe assuming that /tmp has sticky bit.
+ #
+ # # Sequential echo server.
+ # # It services only one client at a time.
+ # Socket.unix_server_loop("/tmp/sock") {|sock, client_addrinfo|
+ # begin
+ # IO.copy_stream(sock, sock)
+ # ensure
+ # sock.close
+ # end
+ # }
+ #
+ def self.unix_server_loop(path, &b) # :yield: socket, client_addrinfo
+ unix_server_socket(path) {|serv|
+ accept_loop(serv, &b)
+ }
+ end
+
+ # call-seq:
+ # socket.connect_nonblock(remote_sockaddr, [options]) => 0
+ #
+ # Requests a connection to be made on the given +remote_sockaddr+ after
+ # O_NONBLOCK is set for the underlying file descriptor.
+ # Returns 0 if successful, otherwise an exception is raised.
+ #
+ # === Parameter
+ # # +remote_sockaddr+ - the +struct+ sockaddr contained in a string or Addrinfo object
+ #
+ # === Example:
+ # # Pull down Google's web page
+ # require 'socket'
+ # include Socket::Constants
+ # socket = Socket.new(AF_INET, SOCK_STREAM, 0)
+ # sockaddr = Socket.sockaddr_in(80, 'www.google.com')
+ # begin # emulate blocking connect
+ # socket.connect_nonblock(sockaddr)
+ # rescue IO::WaitWritable
+ # IO.select(nil, [socket]) # wait 3-way handshake completion
+ # begin
+ # socket.connect_nonblock(sockaddr) # check connection failure
+ # rescue Errno::EISCONN
+ # end
+ # end
+ # socket.write("GET / HTTP/1.0\r\n\r\n")
+ # results = socket.read
+ #
+ # Refer to Socket#connect for the exceptions that may be thrown if the call
+ # to _connect_nonblock_ fails.
+ #
+ # Socket#connect_nonblock may raise any error corresponding to connect(2) failure,
+ # including Errno::EINPROGRESS.
+ #
+ # If the exception is Errno::EINPROGRESS,
+ # it is extended by IO::WaitWritable.
+ # So IO::WaitWritable can be used to rescue the exceptions for retrying connect_nonblock.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that connect_nonblock should not raise an IO::WaitWritable exception, but
+ # return the symbol +:wait_writable+ instead.
+ #
+ # === See
+ # # Socket#connect
+ def connect_nonblock(addr, exception: true)
+ __connect_nonblock(addr, exception)
+ end
+end
+
+class UDPSocket < IPSocket
+
+ # call-seq:
+ # udpsocket.recvfrom_nonblock(maxlen [, flags[, outbuf [, options]]]) => [mesg, sender_inet_addr]
+ #
+ # Receives up to _maxlen_ bytes from +udpsocket+ using recvfrom(2) after
+ # O_NONBLOCK is set for the underlying file descriptor.
+ # _flags_ is zero or more of the +MSG_+ options.
+ # The first element of the results, _mesg_, is the data received.
+ # The second element, _sender_inet_addr_, is an array to represent the sender address.
+ #
+ # When recvfrom(2) returns 0,
+ # Socket#recvfrom_nonblock returns an empty string as data.
+ # It means an empty packet.
+ #
+ # === Parameters
+ # * +maxlen+ - the number of bytes to receive from the socket
+ # * +flags+ - zero or more of the +MSG_+ options
+ # * +outbuf+ - destination String buffer
+ # * +options+ - keyword hash, supporting `exception: false`
+ #
+ # === Example
+ # require 'socket'
+ # s1 = UDPSocket.new
+ # s1.bind("127.0.0.1", 0)
+ # s2 = UDPSocket.new
+ # s2.bind("127.0.0.1", 0)
+ # s2.connect(*s1.addr.values_at(3,1))
+ # s1.connect(*s2.addr.values_at(3,1))
+ # s1.send "aaa", 0
+ # begin # emulate blocking recvfrom
+ # p s2.recvfrom_nonblock(10) #=> ["aaa", ["AF_INET", 33302, "localhost.localdomain", "127.0.0.1"]]
+ # rescue IO::WaitReadable
+ # IO.select([s2])
+ # retry
+ # end
+ #
+ # Refer to Socket#recvfrom for the exceptions that may be thrown if the call
+ # to _recvfrom_nonblock_ fails.
+ #
+ # UDPSocket#recvfrom_nonblock may raise any error corresponding to recvfrom(2) failure,
+ # including Errno::EWOULDBLOCK.
+ #
+ # If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN,
+ # it is extended by IO::WaitReadable.
+ # So IO::WaitReadable can be used to rescue the exceptions for retrying recvfrom_nonblock.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that recvfrom_nonblock should not raise an IO::WaitReadable exception, but
+ # return the symbol +:wait_readable+ instead.
+ #
+ # === See
+ # * Socket#recvfrom
+ def recvfrom_nonblock(len, flag = 0, outbuf = nil, exception: true)
+ __recvfrom_nonblock(len, flag, outbuf, exception)
+ end
+end
+
+class TCPServer < TCPSocket
+
+ # call-seq:
+ # tcpserver.accept_nonblock([options]) => tcpsocket
+ #
+ # Accepts an incoming connection using accept(2) after
+ # O_NONBLOCK is set for the underlying file descriptor.
+ # It returns an accepted TCPSocket for the incoming connection.
+ #
+ # === Example
+ # require 'socket'
+ # serv = TCPServer.new(2202)
+ # begin # emulate blocking accept
+ # sock = serv.accept_nonblock
+ # rescue IO::WaitReadable, Errno::EINTR
+ # IO.select([serv])
+ # retry
+ # end
+ # # sock is an accepted socket.
+ #
+ # Refer to Socket#accept for the exceptions that may be thrown if the call
+ # to TCPServer#accept_nonblock fails.
+ #
+ # TCPServer#accept_nonblock may raise any error corresponding to accept(2) failure,
+ # including Errno::EWOULDBLOCK.
+ #
+ # If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED, Errno::EPROTO,
+ # it is extended by IO::WaitReadable.
+ # So IO::WaitReadable can be used to rescue the exceptions for retrying accept_nonblock.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that accept_nonblock should not raise an IO::WaitReadable exception, but
+ # return the symbol +:wait_readable+ instead.
+ #
+ # === See
+ # * TCPServer#accept
+ # * Socket#accept
+ def accept_nonblock(exception: true)
+ __accept_nonblock(exception)
+ end
+end
+
+class UNIXServer < UNIXSocket
+ # call-seq:
+ # unixserver.accept_nonblock([options]) => unixsocket
+ #
+ # Accepts an incoming connection using accept(2) after
+ # O_NONBLOCK is set for the underlying file descriptor.
+ # It returns an accepted UNIXSocket for the incoming connection.
+ #
+ # === Example
+ # require 'socket'
+ # serv = UNIXServer.new("/tmp/sock")
+ # begin # emulate blocking accept
+ # sock = serv.accept_nonblock
+ # rescue IO::WaitReadable, Errno::EINTR
+ # IO.select([serv])
+ # retry
+ # end
+ # # sock is an accepted socket.
+ #
+ # Refer to Socket#accept for the exceptions that may be thrown if the call
+ # to UNIXServer#accept_nonblock fails.
+ #
+ # UNIXServer#accept_nonblock may raise any error corresponding to accept(2) failure,
+ # including Errno::EWOULDBLOCK.
+ #
+ # If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED or Errno::EPROTO,
+ # it is extended by IO::WaitReadable.
+ # So IO::WaitReadable can be used to rescue the exceptions for retrying accept_nonblock.
+ #
+ # By specifying a keyword argument _exception_ to +false+, you can indicate
+ # that accept_nonblock should not raise an IO::WaitReadable exception, but
+ # return the symbol +:wait_readable+ instead.
+ #
+ # === See
+ # * UNIXServer#accept
+ # * Socket#accept
+ def accept_nonblock(exception: true)
+ __accept_nonblock(exception)
+ end
+end if defined?(UNIXSocket)