fiddle_ffi.rb

require 'ffi'
require 'fiddle'
require 'benchmark'

def setup
  open("/tmp/test.c","w") do |io|
    c_src = <<-EOS
    int add(int a, int b){
      return a + b;
    }

    int add2(int a, int b){
      return a + b;
    }

    EOS

    io.print(c_src)
  end

  `gcc -shared /tmp/test.c -o /tmp/libtest.so`
end

setup

LIB_PATH= "/tmp/libtest.so"

module FFILib
  extend FFI::Library
  ffi_lib LIB_PATH
  attach_function :add, [ :int, :int ], :int, :blocking => false
  attach_function :add2, [ :int, :int ], :int, :blocking => true
end


lib = Fiddle.dlopen(LIB_PATH)

fiddle_add = Fiddle::Function.new(
  lib['add'],  [Fiddle::TYPE_INT, Fiddle::TYPE_INT],  Fiddle::TYPE_INT
)

p 3 == fiddle_add.call(1,2)
p 3 == FFILib.add(1,2)
p 3 == FFILib.add2(1,2)

n=1000000
Benchmark.bmbm(10) do |x|
  x.report("fiddle") { n.times{ fiddle_add.call(1,1) }}
  x.report("ffi-nonblocking"){ n.times{ FFILib.add(1,1)  }}
  x.report("ffi-blocking"){ n.times{ FFILib.add2(1,1)  }}
end

Output:

true
true
true
Rehearsal ---------------------------------------------------
fiddle            1.000000   0.170000   1.170000 (  1.166142)
ffi-nonblocking   0.140000   0.000000   0.140000 (  0.143218)
ffi-blocking      0.450000   0.170000   0.620000 (  0.615898)
------------------------------------------ total: 1.930000sec

                      user     system      total        real
fiddle            0.980000   0.170000   1.150000 (  1.143717)
ffi-nonblocking   0.130000   0.000000   0.130000 (  0.132647)
ffi-blocking      0.450000   0.160000   0.610000 (  0.618110)