# re2 (http://github.com/mudge/re2)
# Ruby bindings to re2, an "efficient, principled regular expression library"
#
# Copyright (c) 2010-2012, Paul Mucur (http://mudge.name)
# Released under the BSD Licence, please see LICENSE.txt

require 'mkmf'

if ENV["CC"]
  RbConfig::MAKEFILE_CONFIG["CC"] = ENV["CC"]
  RbConfig::CONFIG["CC"] = ENV["CC"]
end

if ENV["CXX"]
  RbConfig::MAKEFILE_CONFIG["CXX"] = ENV["CXX"]
  RbConfig::CONFIG["CXX"] = ENV["CXX"]
end

incl, lib = dir_config("re2", "/usr/local/include", "/usr/local/lib")

$CFLAGS << " -Wall -Wextra -funroll-loops"

# Pass -x c++ to force gcc to compile the test program
# as C++ (as it will end in .c by default).
compile_options = "-x c++"

have_library("stdc++")
have_header("stdint.h")
have_func("rb_str_sublen")

unless have_library("re2")
  abort "You must have re2 installed and specified with --with-re2-dir, please see https://github.com/google/re2/wiki/Install"
end

# Recent versions of re2 now require a compiler with C++11 support
checking_for("re2 requires C++11 compiler") do
  minimal_program = <<SRC
#include <re2/re2.h>
int main() { return 0; }
SRC

  unless try_compile(minimal_program, compile_options)
    if try_compile(minimal_program, compile_options + " -std=c++11")
      compile_options << " -std=c++11"
      $CPPFLAGS << " -std=c++11"
    elsif try_compile(minimal_program, compile_options + " -std=c++0x")
      compile_options << " -std=c++0x"
      $CPPFLAGS << " -std=c++0x"
    else
      abort "Cannot compile re2 with your compiler: recent versions require C++11 support."
    end
  end
end

# Determine which version of re2 the user has installed.
# Revision d9f8806c004d added an `endpos` argument to the
# generic Match() function.
#
# To test for this, try to compile a simple program that uses
# the newer form of Match() and set a flag if it is successful.
checking_for("RE2::Match() with endpos argument") do
  test_re2_match_signature = <<SRC
#include <re2/re2.h>

int main() {
  RE2 pattern("test");
  re2::StringPiece *match;
  pattern.Match("test", 0, 0, RE2::UNANCHORED, match, 0);

  return 0;
}
SRC

  if try_compile(test_re2_match_signature, compile_options)
    $defs.push("-DHAVE_ENDPOS_ARGUMENT")
  end
end

create_makefile("re2")