* io.c (rb_readwrite_syserr_fail): works with the given errno than
  thread local errno.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53265 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

* file.c, io.c, util.c: prefer rb_syserr_fail with saved errno
  over setting errno then call rb_sys_fail, not to be clobbered
  potentially and to reduce thread local errno accesses.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53264 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

[ruby-core:72445] [Bug #11862]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53259 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53244 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

* ext/socket/init.c (rsock_init_sock): check FD after validating
* test/socket/test_basicsocket.rb (test_for_fd): new
  [ruby-core:72418] [Bug #11854]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53231 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

accept(2) documents ENOMEM as a possible error, handle it
consistent with all of our other FD-allocating wrappers.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52727 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

* dir.c (dir_initialize): use rb_gc_for_fd for ENOMEM
* ext/socket/init.c (rsock_socket): ditto
* ext/socket/socket.c (rsock_socketpair): ditto
* internal.h (rb_gc_for_fd): prototype
* io.c (rb_gc_for_fd): remove static
  [ruby-core:71623] [Feature #11727]

Manpages for opendir(2), socket(2), and socketpair(3posix)
describe ENOMEM as a possible error for each of these;
handle it consistently with our existing wrappers for
open(2)/pipe(2) etc...

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52726 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

* ext/socket/init.c (is_socket): extract predicate to see if the
  given fd is a socket.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52605 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

* ext/socket/init.c (rsock_s_accept_nonblock): avoid parsing args
  [ruby-core:71439] [Feature #11339]
* ext/socket/rubysocket.h: adjust prototype
* ext/socket/socket.c (sock_accept_nonblock): make private
* ext/socket/tcpserver.c (tcp_accept_nonblock): ditto
* ext/socket/unixserver.c (unix_accept_nonblock): ditto
* ext/socket/lib/socket.rb (Socket#accept_nonblock):
  implement as wrapper, move RDoc
  (TCPServer#accept_nonblock): ditto
  (UNIXServer#accept_nonblock): ditto

target 0: a (ruby 2.3.0dev (2015-11-12 trunk 52550) [x86_64-linux])
target 1: b (ruby 2.3.0dev (2015-11-12 avoid-kwarg-capi 52550) [x86_64-linux]

-----------------------------------------------------------
accept_nonblock

require 'tempfile'
require 'socket'
require 'io/wait'
nr = 500000
Tempfile.create(%w(accept_nonblock .sock)) do |tmp|
  path = tmp.path
  File.unlink(path)
  s = UNIXServer.new(path)
  addr = Socket.sockaddr_un(path).freeze
  nr.times do
    s.accept_nonblock(exception: false)
    c = UNIXSocket.new(path)
    s.wait_readable
    s.accept_nonblock(exception: false).close
    c.close
  end
end

-----------------------------------------------------------
raw data:

[["accept_nonblock",
  [[4.807877402752638,
    4.930681671947241,
    4.738454818725586,
    4.69268161803484,
    4.684675686061382],
   [4.253904823213816,
    4.255124930292368,
    4.295955188572407,
    4.248479191213846,
    4.213303029537201]]]]

Elapsed time: 45.123040065 (sec)
-----------------------------------------------------------
benchmark results:
minimum results in each 5 measurements.
Execution time (sec)
name            a       b
accept_nonblock   4.685   4.213

Speedup ratio: compare with the result of `a' (greater is better)
name            b
accept_nonblock   1.112

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52601 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

* ext/socket/init.c (rsock_s_recvfrom_nonblock):
  avoid arg parsing with C API
  [ruby-core:71439] [Feature #11339]
* ext/socket/basicsocket.c (bsock_recv_nonblock):
  adjust for above change, make private
* ext/socket/socket.c (sock_recvfrom_nonblock): ditto
* ext/socket/udpsocket.c (udp_recvfrom_nonblock): ditto
* ext/socket/lib/socket.rb (BasicSocket#recv_nonblock):
  new wrapper for private method, move RDoc
  (Socket#recvfrom_nonblock): ditto
  (UDPSocket#recvfrom_nonblock): ditto

Note, not adding bm_recv_nonblock.rb to benchmark/ directory
since it is non-portable.  It is only in this commit message.

Benchmark results + code
target 0: a (ruby 2.3.0dev (2015-11-12 trunk 52540) [x86_64-linux])
target 1: b (ruby 2.3.0dev (2015-11-12 avoid-kwarg-capi 52540) [x86_64-linux]

-----------------------------------------------------------
recv_nonblock

require 'socket'
nr = 1000000
msg = 'hello world'
buf = ''
size = msg.bytesize
UNIXSocket.pair(:SEQPACKET) do |a, b|
  nr.times do
    a.sendmsg(msg)
    b.recv_nonblock(size, 0, buf, exception: false)
  end
end

-----------------------------------------------------------
raw data:

[["recv_nonblock",
  [[1.83511221408844,
    1.8703329525887966,
    1.8448856547474861,
    1.859263762831688,
    1.8331583738327026],
   [1.5637447573244572,
    1.4062932096421719,
    1.4247371144592762,
    1.4108827747404575,
    1.4802536629140377]]]]

Elapsed time: 16.530452496 (sec)
-----------------------------------------------------------
benchmark results:
minimum results in each 5 measurements.
Execution time (sec)
name          a       b
recv_nonblock   1.833   1.406

Speedup ratio: compare with the result of `a' (greater is better)
name          b
recv_nonblock   1.304

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52598 b2dd03c8-39d4-4d8f-98ff-823fe69b080e