lib/net/*: use io/wait methods instead of IO.select

io/wait is expected to work on any platform where sockets are
supported.  io/wait methods uses fewer allocations and uses
ppoll internally under Linux for better performance on
high-numbered FDs.

[ruby-core:35572] describes the performance advantage of ppoll
on high-numbered FDs.

* lib/net/protocol.rb (rbuf_fill): use IO#wait_*able
* lib/net/http/generic_request.rb (wait_for_continue): ditto

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50326 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Thu Apr 16 05:09:36 2015  Eric Wong  <e@80x24.org>
+
+	* lib/net/protocol.rb (rbuf_fill): use IO#wait_*able
+	* lib/net/http/generic_request.rb (wait_for_continue): ditto
+	  [ruby-core:68891] [Feature #11056]
+
 Wed Apr 15 18:43:43 2015  Koichi Sasada  <ko1@atdot.net>
 
 	* vm_trace.c (rb_tracepoint_new): fix documentation.

lib/net/http/generic_request.rb

@@ -309,7 +309,7 @@ class Net::HTTPGenericRequest
   def wait_for_continue(sock, ver)
     if ver >= '1.1' and @header['expect'] and
         @header['expect'].include?('100-continue')
-      if IO.select([sock.io], nil, nil, sock.continue_timeout)
+      if sock.io.to_io.wait_readable(sock.continue_timeout)
         res = Net::HTTPResponse.read_new(sock)
         unless res.kind_of?(Net::HTTPContinue)
           res.decode_content = @decode_content

lib/net/protocol.rb

@@ -20,6 +20,7 @@
 
 require 'socket'
 require 'timeout'
+require 'io/wait'
 
 module Net # :nodoc:
 
@@ -153,12 +154,12 @@ module Net # :nodoc:
       when String
         return @rbuf << rv
       when :wait_readable
-        IO.select([@io], nil, nil, @read_timeout) or raise Net::ReadTimeout
+        @io.to_io.wait_readable(@read_timeout) or raise Net::ReadTimeout
         # continue looping
       when :wait_writable
         # OpenSSL::Buffering#read_nonblock may fail with IO::WaitWritable.
         # http://www.openssl.org/support/faq.html#PROG10
-        IO.select(nil, [@io], nil, @read_timeout) or raise Net::ReadTimeout
+        @io.to_io.wait_writable(@read_timeout) or raise Net::ReadTimeout
         # continue looping
       when nil
         # callers do not care about backtrace, so avoid allocating for it