diff options
-rw-r--r-- | lib/resolv.rb | 102 | ||||
-rw-r--r-- | test/resolv/test_dns.rb | 19 |
2 files changed, 88 insertions, 33 deletions
diff --git a/lib/resolv.rb b/lib/resolv.rb index 830ba160d2..e296516aa1 100644 --- a/lib/resolv.rb +++ b/lib/resolv.rb @@ -732,35 +732,47 @@ class Resolv def initialize(*nameserver_port) super() @nameserver_port = nameserver_port - @socks_hash = {} - @socks = [] - nameserver_port.each {|host, port| - if host.index(':') - bind_host = "::" - af = Socket::AF_INET6 - else - bind_host = "0.0.0.0" - af = Socket::AF_INET - end - next if @socks_hash[bind_host] - begin - sock = UDPSocket.new(af) - rescue Errno::EAFNOSUPPORT - next # The kernel doesn't support the address family. - end - sock.do_not_reverse_lookup = true - DNS.bind_random_port(sock, bind_host) - @socks << sock - @socks_hash[bind_host] = sock + @initialized = false + @mutex = Thread::Mutex.new + end + + def lazy_initialize + @mutex.synchronize { + next if @initialized + @initialized = true + @socks_hash = {} + @socks = [] + @nameserver_port.each {|host, port| + if host.index(':') + bind_host = "::" + af = Socket::AF_INET6 + else + bind_host = "0.0.0.0" + af = Socket::AF_INET + end + next if @socks_hash[bind_host] + begin + sock = UDPSocket.new(af) + rescue Errno::EAFNOSUPPORT + next # The kernel doesn't support the address family. + end + @socks << sock + @socks_hash[bind_host] = sock + sock.do_not_reverse_lookup = true + DNS.bind_random_port(sock, bind_host) + } } + self end def recv_reply(readable_socks) + lazy_initialize reply, from = readable_socks[0].recvfrom(UDPSize) return reply, [from[3],from[1]] end def sender(msg, data, host, port=Port) + lazy_initialize sock = @socks_hash[host.index(':') ? "::" : "0.0.0.0"] return nil if !sock service = [host, port] @@ -772,9 +784,14 @@ class Resolv end def close - super - @senders.each_key {|service, id| - DNS.free_request_id(service[0], service[1], id) + @mutex.synchronize { + if @initialized + super + @senders.each_key {|service, id| + DNS.free_request_id(service[0], service[1], id) + } + @initialized = false + end } end @@ -798,20 +815,32 @@ class Resolv super() @host = host @port = port - is_ipv6 = host.index(':') - sock = UDPSocket.new(is_ipv6 ? Socket::AF_INET6 : Socket::AF_INET) - @socks = [sock] - sock.do_not_reverse_lookup = true - DNS.bind_random_port(sock, is_ipv6 ? "::" : "0.0.0.0") - sock.connect(host, port) + @mutex = Thread::Mutex.new + @initialized = false + end + + def lazy_initialize + @mutex.synchronize { + next if @initialized + @initialized = true + is_ipv6 = @host.index(':') + sock = UDPSocket.new(is_ipv6 ? Socket::AF_INET6 : Socket::AF_INET) + @socks = [sock] + sock.do_not_reverse_lookup = true + DNS.bind_random_port(sock, is_ipv6 ? "::" : "0.0.0.0") + sock.connect(@host, @port) + } + self end def recv_reply(readable_socks) + lazy_initialize reply = readable_socks[0].recv(UDPSize) return reply, nil end def sender(msg, data, host=@host, port=@port) + lazy_initialize unless host == @host && port == @port raise RequestError.new("host/port don't match: #{host}:#{port}") end @@ -822,10 +851,15 @@ class Resolv end def close - super - @senders.each_key {|from, id| - DNS.free_request_id(@host, @port, id) - } + @mutex.synchronize do + if @initialized + super + @senders.each_key {|from, id| + DNS.free_request_id(@host, @port, id) + } + @initialized = false + end + end end class Sender < Requester::Sender # :nodoc: @@ -839,6 +873,7 @@ class Resolv class MDNSOneShot < UnconnectedUDP # :nodoc: def sender(msg, data, host, port=Port) + lazy_initialize id = DNS.allocate_request_id(host, port) request = msg.encode request[0,2] = [id].pack('n') @@ -848,6 +883,7 @@ class Resolv end def sender_for(addr, msg) + lazy_initialize @senders[msg.id] end end diff --git a/test/resolv/test_dns.rb b/test/resolv/test_dns.rb index 1b44f32807..1ac3aea7b8 100644 --- a/test/resolv/test_dns.rb +++ b/test/resolv/test_dns.rb @@ -3,6 +3,7 @@ require 'test/unit' require 'resolv' require 'socket' require 'tempfile' +require 'minitest/mock' class TestResolvDNS < Test::Unit::TestCase def setup @@ -246,4 +247,22 @@ class TestResolvDNS < Test::Unit::TestCase } assert_operator(2**14, :<, m.to_s.length) end + + def assert_no_fd_leak + socket = assert_throw(self) do |tag| + Resolv::DNS.stub(:bind_random_port, ->(s, *) {throw(tag, s)}) do + yield.getname("8.8.8.8") + end + end + + assert_predicate(socket, :closed?, "file descriptor leaked") + end + + def test_no_fd_leak_connected + assert_no_fd_leak {Resolv::DNS.new(nameserver_port: [['127.0.0.1', 53]])} + end + + def test_no_fd_leak_unconnected + assert_no_fd_leak {Resolv::DNS.new} + end end |