socket: avoid arg parsing in rsock_s_recvfrom_nonblock

* 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

1 files changed, 4 insertions, 9 deletions

diff --git a/ext/socket/init.c b/ext/socket/init.c
index 1710129519..350ba652e7 100644
--- a/ext/socket/init.c
+++ b/ext/socket/init.c
@@ -200,24 +200,19 @@ rsock_s_recvfrom(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from)
 }
 
 VALUE
-rsock_s_recvfrom_nonblock(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from)
+rsock_s_recvfrom_nonblock(VALUE sock, VALUE len, VALUE flg, VALUE str,
+			  VALUE ex, enum sock_recv_type from)
 {
     rb_io_t *fptr;
-    VALUE str;
     union_sockaddr buf;
     socklen_t alen = (socklen_t)sizeof buf;
-    VALUE len, flg;
     long buflen;
     long slen;
     int fd, flags;
     VALUE addr = Qnil;
-    VALUE opts = Qnil;
     socklen_t len0;
 
-    rb_scan_args(argc, argv, "12:", &len, &flg, &str, &opts);
-
-    if (flg == Qnil) flags = 0;
-    else             flags = NUM2INT(flg);
+    flags = NUM2INT(flg);
     buflen = NUM2INT(len);
     str = rsock_strbuf(str, buflen);
 
@@ -249,7 +244,7 @@ rsock_s_recvfrom_nonblock(VALUE sock, int argc, VALUE *argv, enum sock_recv_type
 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
 	  case EWOULDBLOCK:
 #endif
-            if (rsock_opt_false_p(opts, sym_exception))
+            if (ex == Qfalse)
 		return sym_wait_readable;
             rb_readwrite_sys_fail(RB_IO_WAIT_READABLE, "recvfrom(2) would block");
 	}