#
# server.rb -- GenericServer Class
#
# Author: IPR -- Internet Programming with Ruby -- writers
# Copyright (c) 2000, 2001 TAKAHASHI Masayoshi, GOTOU Yuuzou
# Copyright (c) 2002 Internet Programming with Ruby writers. All rights
# reserved.
#
# $IPR: server.rb,v 1.62 2003/07/22 19:20:43 gotoyuzo Exp $
require 'thread'
require 'socket'
require 'webrick/config'
require 'webrick/log'
module WEBrick
##
# Server error exception
class ServerError < StandardError; end
##
# Base server class
class SimpleServer
##
# A SimpleServer only yields when you start it
def SimpleServer.start
yield
end
end
##
# A generic module for daemonizing a process
class Daemon
##
# Performs the standard operations for daemonizing a process. Runs a
# block, if given.
def Daemon.start
exit!(0) if fork
Process::setsid
exit!(0) if fork
Dir::chdir("/")
File::umask(0)
STDIN.reopen("/dev/null")
STDOUT.reopen("/dev/null", "w")
STDERR.reopen("/dev/null", "w")
yield if block_given?
end
end
##
# Base TCP server class. You must subclass GenericServer and provide a #run
# method.
class GenericServer
##
# The server status. One of :Stop, :Running or :Shutdown
attr_reader :status
##
# The server configuration
attr_reader :config
##
# The server logger. This is independent from the HTTP access log.
attr_reader :logger
##
# Tokens control the number of outstanding clients. The
# <code>:MaxClients</code> configuration sets this.
attr_reader :tokens
##
# Sockets listening for connections.
attr_reader :listeners
##
# Creates a new generic server from +config+. The default configuration
# comes from +default+.
def initialize(config={}, default=Config::General)
@config = default.dup.update(config)
@status = :Stop
@config[:Logger] ||= Log::new
@logger = @config[:Logger]
@tokens = SizedQueue.new(@config[:MaxClients])
@config[:MaxClients].times{ @tokens.push(nil) }
webrickv = WEBrick::VERSION
rubyv = "#{RUBY_VERSION} (#{RUBY_RELEASE_DATE}) [#{RUBY_PLATFORM}]"
@logger.info("WEBrick #{webrickv}")
@logger.info("ruby #{rubyv}")
@listeners = []
unless @config[:DoNotListen]
if @config[:Listen]
warn(":Listen option is deprecated; use GenericServer#listen")
end
listen(@config[:BindAddress], @config[:Port])
if @config[:Port] == 0
@config[:Port] = @listeners[0].addr[1]
end
end
end
##
# Retrieves +key+ from the configuration
def [](key)
@config[key]
end
##
# Adds listeners from +address+ and +port+ to the server. See
# WEBrick::Utils::create_listeners for details.
def listen(address, port)
@listeners += Utils::create_listeners(address, port, @logger)
end
##
# Starts the server and runs the +block+ for each connection. This method
# does not return until the server is stopped from a signal handler or
# another thread using #stop or #shutdown.
#
# If the block raises a subclass of StandardError the exception is logged
# and ignored. If an IOError or Errno::EBADF exception is raised the
# exception is ignored. If an Exception subclass is raised the exception
# is logged and re-raised which stops the server.
#
# To completely shut down a server call #shutdown from ensure:
#
# server = WEBrick::GenericServer.new
# # or WEBrick::HTTPServer.new
#
# begin
# server.start
# ensure
# server.shutdown
# end
def start(&block)
raise ServerError, "already started." if @status != :Stop
server_type = @config[:ServerType] || SimpleServer
server_type.start{
@logger.info \
"#{self.class}#start: pid=#{$$} port=#{@config[:Port]}"
call_callback(:StartCallback)
thgroup = ThreadGroup.new
@status = :Running
begin
while @status == :Running
begin
if svrs = IO.select(@listeners, nil, nil, 2.0)
svrs[0].each{|svr|
@tokens.pop # blocks while no token is there.
if sock = accept_client(svr)
sock.do_not_reverse_lookup = config[:DoNotReverseLookup]
th = start_thread(sock, &block)
th[:WEBrickThread] = true
thgroup.add(th)
else
@tokens.push(nil)
end
}
end
rescue Errno::EBADF, IOError => ex
# if the listening socket was closed in GenericServer#shutdown,
# IO::select raise it.
rescue StandardError => ex
msg = "#{ex.class}: #{ex.message}\n\t#{ex.backtrace[0]}"
@logger.error msg
rescue Exception => ex
@logger.fatal ex
raise
end
end
ensure
@status = :Shutdown
@logger.info "going to shutdown ..."
thgroup.list.each{|th| th.join if th[:WEBrickThread] }
call_callback(:StopCallback)
@logger.info "#{self.class}#start done."
@status = :Stop
end
}
end
##
# Stops the server from accepting new connections.
def stop
if @status == :Running
@status = :Shutdown
end
end
##
# Shuts down the server and all listening sockets. New listeners must be
# provided to restart the server.
def shutdown
stop
@listeners.each{|s|
if @logger.debug?
addr = s.addr
@logger.debug("close TCPSocket(#{addr[2]}, #{addr[1]})")
end
begin
s.shutdown
rescue Errno::ENOTCONN
# when `Errno::ENOTCONN: Socket is not connected' on some platforms,
# call #close instead of #shutdown.
# (ignore @config[:ShutdownSocketWithoutClose])
s.close
else
unless @config[:ShutdownSocketWithoutClose]
s.close
end
end
}
@listeners.clear
end
##
# You must subclass GenericServer and implement \#run which accepts a TCP
# client socket
def run(sock)
@logger.fatal "run() must be provided by user."
end
private
# :stopdoc:
##
# Accepts a TCP client socket from the TCP server socket +svr+ and returns
# the client socket.
def accept_client(svr)
sock = nil
begin
sock = svr.accept
sock.sync = true
Utils::set_non_blocking(sock)
Utils::set_close_on_exec(sock)
rescue Errno::ECONNRESET, Errno::ECONNABORTED,
Errno::EPROTO, Errno::EINVAL => ex
rescue StandardError => ex
msg = "#{ex.class}: #{ex.message}\n\t#{ex.backtrace[0]}"
@logger.error msg
end
return sock
end
##
# Starts a server thread for the client socket +sock+ that runs the given
# +block+.
#
# Sets the socket to the <code>:WEBrickSocket</code> thread local variable
# in the thread.
#
# If any errors occur in the block they are logged and handled.
def start_thread(sock, &block)
Thread.start{
begin
Thread.current[:WEBrickSocket] = sock
begin
addr = sock.peeraddr
@logger.debug "accept: #{addr[3]}:#{addr[1]}"
rescue SocketError
@logger.debug "accept: <address unknown>"
raise
end
call_callback(:AcceptCallback, sock)
block ? block.call(sock) : run(sock)
rescue Errno::ENOTCONN
@logger.debug "Errno::ENOTCONN raised"
rescue ServerError => ex
msg = "#{ex.class}: #{ex.message}\n\t#{ex.backtrace[0]}"
@logger.error msg
rescue Exception => ex
@logger.error ex
ensure
@tokens.push(nil)
Thread.current[:WEBrickSocket] = nil
if addr
@logger.debug "close: #{addr[3]}:#{addr[1]}"
else
@logger.debug "close: <address unknown>"
end
sock.close unless sock.closed?
end
}
end
##
# Calls the callback +callback_name+ from the configuration with +args+
def call_callback(callback_name, *args)
if cb = @config[callback_name]
cb.call(*args)
end
end
end # end of GenericServer
end