ruby/lib/mkmf.rb

# module to create Makefile for extension modules
# invoke like: ruby -r mkmf extconf.rb

require 'rbconfig'
require 'find'
require 'shellwords'

CONFIG = Config::MAKEFILE_CONFIG
ORIG_LIBPATH = ENV['LIB']

SRC_EXT = ["c", "cc", "m", "cxx", "cpp", "C"]

unless defined? $configure_args
  $configure_args = {}
  for arg in Shellwords.shellwords(CONFIG["configure_args"])
    arg, val = arg.split('=', 2)
    if arg.sub!(/^(?!--)/, '--')
      val or next
      arg.downcase!
    end
    next if /^--(?:top|topsrc|src|cur)dir$/ =~ arg
    $configure_args[arg] = val || true
  end
  for arg in ARGV
    arg, val = arg.split('=', 2)
    if arg.sub!(/^(?!--)/, '--')
      val or next
      arg.downcase!
    end
    $configure_args[arg] = val || true
  end
end

$srcdir = CONFIG["srcdir"]
$libdir = CONFIG["libdir"]
$rubylibdir = CONFIG["rubylibdir"]
$archdir = CONFIG["archdir"]
$sitedir = CONFIG["sitedir"]
$sitelibdir = CONFIG["sitelibdir"]
$sitearchdir = CONFIG["sitearchdir"]

def dir_re(dir)
  Regexp.new('\$(?:\('+dir+'\)|\{'+dir+'\})(?:\$\(target_prefix\)|\{target_prefix\})?')
end
commondir = dir_re('commondir')

INSTALL_DIRS = [
  [commondir, "$(rubylibdir)"],
  [dir_re('sitelibdir'), "$(rubylibdir)$(target_prefix)"],
  [dir_re('sitearchdir'), "$(archdir)$(target_prefix)"]
]

SITEINSTALL_DIRS = [
  [commondir, "$(sitedir)$(target_prefix)"],
  [dir_re('rubylibdir'), "$(sitelibdir)$(target_prefix)"],
  [dir_re('archdir'), "$(sitearchdir)$(target_prefix)"]
]

if File.exist? Config::CONFIG["archdir"] + "/ruby.h"
  $hdrdir = $archdir
elsif File.exist? $srcdir + "/ruby.h"
  $hdrdir = $srcdir
else
  STDERR.print "can't find header files for ruby.\n"
  exit 1
end
$topdir = $hdrdir
# $hdrdir.gsub!('/', '\\') if RUBY_PLATFORM =~ /mswin32|bccwin32/

CFLAGS = CONFIG["CFLAGS"]
if RUBY_PLATFORM == "m68k-human"
  CFLAGS.gsub!(/-c..-stack=[0-9]+ */, '')
elsif RUBY_PLATFORM =~ /-nextstep|-rhapsody|-darwin/
  CFLAGS.gsub!( /-arch\s\w*/, '' )
end

if /mswin32/ =~ RUBY_PLATFORM
  OUTFLAG = '-Fe'
elsif /bccwin32/ =~ RUBY_PLATFORM
  OUTFLAG = '-o'
else
  OUTFLAG = '-o '
end
LINK = "#{CONFIG['CC']} #{OUTFLAG}conftest -I#{$hdrdir} #{CFLAGS} %s %s #{CONFIG['LDFLAGS']} %s conftest.c %s %s #{CONFIG['LIBS']}"
CPP = "#{CONFIG['CPP']} -E %s -I#{$hdrdir} #{CFLAGS} %s %s conftest.c"

def rm_f(*files)
  targets = []
  for file in files
    targets.concat Dir[file]
  end
  if not targets.empty?
    File::chmod(0777, *targets)
    File::unlink(*targets)
  end
end

$log = nil
$orgerr = $stderr.dup
$orgout = $stdout.dup

def xsystem command
  Config.expand(command)
  if $DEBUG
    puts command
    return system(command)
  end
  $log ||= open('mkmf.log', 'w')
  $stderr.reopen($log) 
  $stdout.reopen($log) 
  puts command
  r = system(command)
  $stderr.reopen($orgerr)
  $stdout.reopen($orgout)
  return r
end

def try_link0(src, opt="")
  cfile = open("conftest.c", "w")
  cfile.print src
  cfile.close
  ldflags = $LDFLAGS
  if /mswin32|bccwin32/ =~ RUBY_PLATFORM and !$LIBPATH.empty?
    ENV['LIB'] = ($LIBPATH + [ORIG_LIBPATH]).compact.join(';')
  else
    $LDFLAGS = ldflags.dup
    $LIBPATH.each {|d| $LDFLAGS << " -L" + d}
  end
  begin
    xsystem(Config.expand(format(LINK, $CFLAGS, $CPPFLAGS, $LDFLAGS, opt, $LOCAL_LIBS)))
  ensure
    $LDFLAGS = ldflags
    ENV['LIB'] = ORIG_LIBPATH if /mswin32|bccwin32/ =~ RUBY_PLATFORM
  end
end

def try_link(src, opt="")
  begin
    try_link0(src, opt)
  ensure
    rm_f "conftest*"
    if /bccwin32/ =~ RUBY_PLATFORM
      rm_f "c0x32*"
    end
  end
end

def try_cpp(src, opt="")
  cfile = open("conftest.c", "w")
  cfile.print src
  cfile.close
  begin
    xsystem(Config.expand(format(CPP, $CPPFLAGS, $CFLAGS, opt)))
  ensure
    rm_f "conftest*"
  end
end

def egrep_cpp(pat, src, opt="")
  cfile = open("conftest.c", "w")
  cfile.print src
  cfile.close
  begin
    xsystem(Config.expand(format(CPP, $CPPFLAGS, $CFLAGS, opt))+"|egrep #{pat}")
  ensure
    rm_f "conftest*"
  end
end

def try_run(src, opt="")
  begin
    if try_link0(src, opt)
      if xsystem("./conftest")
	true
      else
	false
      end
    else
      nil
    end
  ensure
    rm_f "conftest*"
  end
end

def install_files(mfile, ifiles, map = INSTALL_DIRS, srcprefix = nil)
  ifiles or return
  srcprefix ||= '$(srcdir)'
  Config::expand(srcdir = srcprefix.dup)
  dirs = []
  path = Hash.new {|h, i| h[i] = dirs.push([i])[-1]}
  ifiles.each do |files, dir, prefix|
    dir = map.inject(dir) {|dir, (orig, new)| dir.gsub(orig, new)} if map
    prefix = %r"\A#{Regexp.quote(prefix)}/?" if prefix
    if( files[0,2] == "./" )
      # install files which are in current working directory.
      Dir.glob(files) do |f|
	d = File.dirname(f)
	d.sub!(prefix, "") if prefix
	d = (d.empty? || d == ".") ? dir : File.join(dir,d)
	path[d] << f
      end
    else
      # install files which are under the $(srcdir).
      Dir.glob(File.join(srcdir,files)) do |f|
	f[0..srcdir.size] = ""
	d = File.dirname(f)
	d.sub!(prefix, "") if prefix
	d = (d.empty? || d == ".") ? dir : File.join(dir, d)
	path[d] << (srcprefix ? File.join(srcprefix, f) : f)
      end
    end
  end

  dirs.each do |dir, *files|
    mfile.printf("\t@$(MAKEDIRS) %s\n", dir)
    files.each do |f|
      mfile.printf("\t@$(INSTALL_DATA) %s %s\n", f, dir)
    end
  end
end

def install_rb(mfile, dest, srcdir = nil)
  install_files(mfile, [["lib/**/*.rb", dest, "lib"]], nil, srcdir)
end

def append_library(libs, lib)
  if /mswin32|bccwin32/ =~ RUBY_PLATFORM
    lib + ".lib " + libs
  else
    "-l" + lib + " " + libs
  end
end

def have_library(lib, func="main")
  printf "checking for %s() in -l%s... ", func, lib
  STDOUT.flush

  if func && func != ""
    libs = append_library($libs, lib)
    if /mswin32|bccwin32|mingw/ =~ RUBY_PLATFORM
      if lib == 'm'
	print "yes\n"
	return true
      end
      r = try_link(<<"SRC", libs)
#include <windows.h>
#include <winsock.h>
int main() { return 0; }
int t() { #{func}(); return 0; }
SRC
      unless r
        r = try_link(<<"SRC", libs)
#include <windows.h>
#include <winsock.h>
int main() { return 0; }
int t() { void ((*p)()); p = (void ((*)()))#{func}; return 0; }
SRC
      end
    else
      r = try_link(<<"SRC", libs)
int main() { return 0; }
int t() { #{func}(); return 0; }
SRC
    end
    unless r
      print "no\n"
      return false
    end
  else
    libs = append_library($libs, lib)
  end

  $libs = libs
  print "yes\n"
  return true
end

def find_library(lib, func, *paths)
  printf "checking for %s() in -l%s... ", func, lib
  STDOUT.flush

  libpath = $LIBPATH
  libs = append_library($libs, lib)
  until try_link(<<"SRC", libs)
int main() { return 0; }
int t() { #{func}(); return 0; }
SRC
    if paths.size == 0
      $LIBPATH = libpath
      print "no\n"
      return false
    end
    $LIBPATH = libpath | [paths.shift]
  end
  $libs = libs
  print "yes\n"
  return true
end

def have_func(func, header=nil)
  printf "checking for %s()... ", func
  STDOUT.flush

  libs = $libs
  src = 
    if /mswin32|bccwin32|mingw/ =~ RUBY_PLATFORM
      r = <<"SRC"
#include <windows.h>
#include <winsock.h>
SRC
    else
      ""
    end
  unless header.nil?
  src << <<"SRC"
#include <#{header}>
SRC
  end
  r = try_link(src + <<"SRC", libs)
int main() { return 0; }
int t() { #{func}(); return 0; }
SRC
  unless r
    r = try_link(src + <<"SRC", libs)
int main() { return 0; }
int t() { void ((*p)()); p = (void ((*)()))#{func}; return 0; }
SRC
  end
  unless r
    print "no\n"
    return false
  end
  $defs.push(format("-DHAVE_%s", func.upcase))
  print "yes\n"
  return true
end

def have_header(header)
  printf "checking for %s... ", header
  STDOUT.flush

  unless try_cpp(<<"SRC")
#include <#{header}>
SRC
    print "no\n"
    return false
  end
  $defs.push(format("-DHAVE_%s", header.tr("a-z./\055", "A-Z___")))
  print "yes\n"
  return true
end

def arg_config(config, default=nil)
  $configure_args.fetch(config, default)
end

def with_config(config, default=nil)
  unless /^--with-/ =~ config
    config = '--with-' + config
  end
  arg_config(config, default)
end

def enable_config(config, default=nil)
  if arg_config("--enable-"+config)
    true
  elsif arg_config("--disable-"+config)
    false
  else
    default
  end
end

def create_header()
  print "creating extconf.h\n"
  STDOUT.flush
  if $defs.length > 0
    hfile = open("extconf.h", "w")
    for line in $defs
      line =~ /^-D(.*)/
      hfile.printf "#define %s 1\n", $1
    end
    hfile.close
  end
end

def dir_config(target, idefault=nil, ldefault=nil)
  if dir = with_config(target + "-dir", (idefault unless ldefault))
    idefault = dir + "/include"
    ldefault = dir + "/lib"
  end

  idir = with_config(target + "-include", idefault)
  ldir = with_config(target + "-lib", ldefault)

  if idir
    idircflag = "-I" + idir
    $CPPFLAGS += " " + idircflag unless $CPPFLAGS.split.include?(idircflag)
  end

  if ldir
    $LIBPATH << ldir unless $LIBPATH.include?(ldir)
  end

  [idir, ldir]
end

def with_destdir(dir)
  /^\$[\(\{]/ =~ dir ? dir : "$(DESTDIR)"+dir
end

def winsep(s)
  s.tr('/', '\\')
end

def create_makefile(target, srcprefix = nil)
  save_libs = $libs.dup
  save_libpath = $LIBPATH.dup
  print "creating Makefile\n"
  rm_f "conftest*"
  STDOUT.flush
  if target.include?('/')
    target_prefix, target = File.split(target)
    target_prefix[0,0] = '/'
  else
    target_prefix = ""
  end
  if CONFIG["DLEXT"] == $OBJEXT
    libs = $libs.split
    for lib in libs
      lib.sub!(/-l(.*)/, '"lib\1.a"')
    end
    $defs.push(format("-DEXTLIB='%s'", libs.join(",")))
  end
  $DLDFLAGS = CONFIG["DLDFLAGS"]

  $libs = CONFIG["LIBRUBYARG"] + " " + $libs
  $configure_args['--enable-shared'] or $LIBPATH |= [$topdir]
  $LIBPATH |= [CONFIG["libdir"]]

  srcprefix ||= '$(srcdir)'
  Config::expand(srcdir = srcprefix.dup)
  defflag = ''
  if RUBY_PLATFORM =~ /bccwin32/
    deffile = target + '.def'
    if not File.exist? deffile
      open(deffile, 'wb') do |f|
        f.print "EXPORTS\n", "_Init_", target, "\n"
      end
    end
  elsif RUBY_PLATFORM =~ /cygwin|mingw/
    deffile = target + '.def'
    if not File.exist? deffile
      if File.exist? File.join srcdir, deffile
	deffile = File.join srcdir, deffile
      else
        open(deffile, 'wb') do |f|
          f.print "EXPORTS\n", "Init_", target, "\n"
        end
      end
    end
    defflag = deffile
  end

  if RUBY_PLATFORM =~ /mswin32|bccwin32/
    libpath = $LIBPATH.join(';')
  else
    $LIBPATH.each {|d| $DLDFLAGS << " -L" << d}
    if /netbsdelf/ =~ RUBY_PLATFORM
      $LIBPATH.each {|d| $DLDFLAGS << " -Wl,-R" + d}
    end
  end
  drive = File::PATH_SEPARATOR == ';' ? /\A\w:/ : /\A/

  unless $objs then
    $objs = []
    for f in Dir[File.join(srcdir, "*.{#{SRC_EXT.join(%q{,})}}")]
      f = File.basename(f)
      f.sub!(/(#{SRC_EXT.join(%q{|})})$/, $OBJEXT)
      $objs.push f
    end
  else
    for i in $objs
      i.sub!(/\.o\z/, ".#{$OBJEXT}")
    end
  end
  $objs = $objs.join(" ")

  mfile = open("Makefile", "w")
  mfile.binmode if /mingw/ =~ RUBY_PLATFORM
  mfile.print  <<EOMF
SHELL = /bin/sh

#### Start of system configuration section. ####

srcdir = #{srcdir}
topdir = #{$topdir}
hdrdir = #{$hdrdir}
VPATH = $(srcdir)

CC = #{CONFIG["CC"]}

CFLAGS   = #{CONFIG["CCDLFLAGS"]} #{CFLAGS} #{$CFLAGS}
CPPFLAGS = -I. -I$(hdrdir) -I$(srcdir) #{$defs.join(" ")} #{CONFIG["CPPFLAGS"]} #{$CPPFLAGS}
CXXFLAGS = $(CFLAGS)
#{
if /bccwin32/ =~ RUBY_PLATFORM
  "DLDFLAGS = #$LDFLAGS -L\"$(topdir:/=\\)\"\n" +
  "LDSHARED = #{CONFIG['LDSHARED']}\n"
else
  "DLDFLAGS = #{$DLDFLAGS} #{$LDFLAGS}\n" +
  "LDSHARED = #{CONFIG['LDSHARED']} #{defflag}\n"
end
}
LIBPATH = #{libpath}

RUBY_INSTALL_NAME = #{CONFIG["RUBY_INSTALL_NAME"]}
RUBY_SO_NAME = #{CONFIG["RUBY_SO_NAME"]}
arch = #{CONFIG["arch"]}
ruby_version = #{Config::CONFIG["ruby_version"]}
EOMF
  if destdir = CONFIG["prefix"].scan(drive)[0] and !destdir.empty?
    mfile.print "\nDESTDIR = ", destdir, "\n"
  end
  CONFIG.each do |key, var|
    next unless /prefix$/ =~ key
    mfile.print key, " = ", with_destdir(var.sub(drive, '')), "\n"
  end
  CONFIG.each do |key, var|
    next unless /^(?:src|top|(.*))dir$/ =~ key and $1
    mfile.print key, " = ", with_destdir(var.sub(drive, '')), "\n"
  end
  mfile.print  <<EOMF
target_prefix = #{target_prefix}

#### End of system configuration section. ####

LOCAL_LIBS = #{$LOCAL_LIBS} #{$local_flags}
LIBS = #{$libs}
OBJS = #{$objs}

TARGET = #{target}
DLLIB = $(TARGET).#{CONFIG["DLEXT"]}

RUBY = #{CONFIG["ruby_install_name"]}
RM = $(RUBY) -rftools -e "File::rm_f(*ARGV.map do|x|Dir[x]end.flatten.uniq)"
MAKEDIRS = $(RUBY) -r ftools -e 'File::makedirs(*ARGV)'
INSTALL_PROG = $(RUBY) -r ftools -e 'File::install(ARGV[0], ARGV[1], 0555, true)'
INSTALL_DATA = $(RUBY) -r ftools -e 'File::install(ARGV[0], ARGV[1], 0644, true)'

EXEEXT = #{CONFIG["EXEEXT"]}

all:		$(DLLIB)

clean:
		@$(RM) *.#{$OBJEXT} *.so *.sl *.a $(DLLIB)
#{
if /bccwin32/ =~ RUBY_PLATFORM
   "		@$(RM) $(TARGET).lib $(TARGET).def $(TARGET).ilc $(TARGET).ild $(TARGET).ilf $(TARGET).ils $(TARGET).tds $(TARGET).map $(CLEANFILES)\n"+
   "		@if exist $(target).def.org ren $(target).def.org $(target).def"
else
   "		@$(RM) $(TARGET).lib $(TARGET).exp $(TARGET).ilk *.pdb $(CLEANFILES)"
end
}
                
distclean:	clean
		@$(RM) Makefile extconf.h conftest.* mkmf.log
		@$(RM) core ruby$(EXEEXT) *~ $(DISTCLEANFILES)

realclean:	distclean

install:	$(archdir)$(target_prefix)/$(DLLIB)

site-install:	$(sitearchdir)$(target_prefix)/$(DLLIB)

$(archdir)$(target_prefix)/$(DLLIB): $(DLLIB)
	@$(MAKEDIRS) $(rubylibdir) $(archdir)$(target_prefix)
	@$(INSTALL_PROG) $(DLLIB) $(archdir)$(target_prefix)/$(DLLIB)

$(sitearchdir)$(target_prefix)/$(DLLIB): $(DLLIB)
	@$(MAKEDIRS) $(sitearchdir)$(target_prefix)
	@$(INSTALL_PROG) $(DLLIB) $(sitearchdir)$(target_prefix)/$(DLLIB)

EOMF
  mfile.print "install:\n"
  install_rb(mfile, "$(rubylibdir)$(target_prefix)", srcprefix)
  install_files(mfile, $INSTALLFILES, INSTALL_DIRS, srcprefix)
  mfile.print "\n"
  mfile.print "site-install:\n"
  install_rb(mfile, "$(sitelibdir)$(target_prefix)", srcprefix)
  install_files(mfile, $INSTALLFILES, SITEINSTALL_DIRS, srcprefix)

  unless /mswin32/ =~ RUBY_PLATFORM
    if /bccwin32/ =~ RUBY_PLATFORM
      src = '$(<:\\=/)'
    else
      src = '$<'
    end
    copt = cxxopt = ''
  else
    if /nmake/i =~ $make
      src = '$(<:\\=/)'
    else
      src = '$(subst /,\\\\,$<)'
    end
    copt = '-Tc'
    cxxopt = '-Tp'
  end
  unless /nmake/i =~ $make
    if /bccwin32/ =~ RUBY_PLATFORM
    mfile.print "
{$(srcdir)}.cc{}.@OBJEXT@:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
{$(srcdir)}.cpp{}.@OBJEXT@:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
{$(srcdir)}.cxx{}.@OBJEXT@:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
{$(srcdir)}.c{}.@OBJEXT@:
	$(CC) $(CFLAGS) $(CPPFLAGS) -c #{copt}#{src}
"
    end
    mfile.puts "
.cc.#{$OBJEXT}:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
.cpp.#{$OBJEXT}:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
.cxx.#{$OBJEXT}:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
.C.#{$OBJEXT}:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
.c.#{$OBJEXT}:
	$(CC) $(CFLAGS) $(CPPFLAGS) -c #{copt}#{src}
"
  else
    mfile.print "
{$(srcdir)}.c{}.#{$OBJEXT}:
	$(CC) -I. -I$(<D) $(CFLAGS) $(CPPFLAGS) -c #{copt}#{src}
.c.#{$OBJEXT}:
	$(CC) $(CFLAGS) $(CPPFLAGS) -c #{copt}#{src}
{$(srcdir)}.cc{}.#{$OBJEXT}:
	$(CXX) -I. -I$(<D) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
.cc.#{$OBJEXT}:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
{$(srcdir)}.cpp{}.#{$OBJEXT}:
	$(CXX) -I. -I$(<D) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
.cpp.#{$OBJEXT}:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
{$(srcdir)}.cxx{}.#{$OBJEXT}:
	$(CXX) -I. -I$(<D) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
.cxx.#{$OBJEXT}:
	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -c #{cxxopt}#{src}
"
  end

  if CONFIG["DLEXT"] != $OBJEXT
    mfile.print "$(DLLIB): $(OBJS)\n"
    if /bccwin32/ =~ RUBY_PLATFORM
      mfile.print "\t$(LDSHARED) $(DLDFLAGS) C0D32.OBJ $(OBJS), $@,, CW32.LIB IMPORT32.LIB WS2_32.LIB $(LIBS), #{deffile}\n"
    else
      if /mswin32|bccwin32/ =~ RUBY_PLATFORM
        if /nmake/i =~ $make
          mfile.print "\tset LIB=$(LIBPATH:/=\\);$(LIB)\n"
        else
          mfile.print "\tenv LIB='$(subst /,\\\\,$(LIBPATH));$(LIB)' \\\n"
        end
      end
      mfile.print "\t$(LDSHARED) $(DLDFLAGS) #{OUTFLAG}$(DLLIB) $(OBJS) $(LIBS) $(LOCAL_LIBS)\n"
    end
  elsif not File.exist?(target + ".c") and not File.exist?(target + ".cc")
    mfile.print "$(DLLIB): $(OBJS)\n"
    case RUBY_PLATFORM
    when "m68k-human"
      mfile.printf "ar cru $(DLLIB) $(OBJS)\n"
    else
      mfile.printf "ld $(DLDFLAGS) -r -o $(DLLIB) $(OBJS)\n"
    end
  end

  depend = File.join(srcdir, "depend")
  if File.exist?(depend)
    dfile = open(depend, "r")
    mfile.printf "###\n"
    while line = dfile.gets()
      line.gsub!(/\.o\b/, ".#{$OBJEXT}")
      line.gsub!(/(\s)([^\s\/]+\.[ch])/, '\1{$(srcdir)}\2') if /nmake/i =~ $make
      mfile.printf "%s", line
    end
    dfile.close
  end
  mfile.close
  $libs = save_libs
  $LIBPATH = save_libpath
end

$OBJEXT = CONFIG["OBJEXT"]
$objs = nil
$libs = CONFIG["DLDLIBS"]
$local_flags = ""
case RUBY_PLATFORM
when /mswin32/
  $local_flags = "-link /INCREMENTAL:no /EXPORT:Init_$(TARGET)"
end
$LOCAL_LIBS = ""
$defs = []

$make = with_config("make-prog", ENV["MAKE"] || "make")

$CFLAGS = with_config("cflags", arg_config("CFLAGS", ""))
$CPPFLAGS = with_config("cppflags", arg_config("CPPFLAGS", ""))
$LDFLAGS = with_config("ldflags", arg_config("LDFLAGS", ""))
$LIBPATH = []

dir_config("opt")

Config::CONFIG["srcdir"] = CONFIG["srcdir"] =
  $srcdir = arg_config("--srcdir", File.dirname($0))
$configure_args["--topsrcdir"] ||= $srcdir
Config::CONFIG["topdir"] = CONFIG["topdir"] =
  $curdir = arg_config("--curdir", Dir.pwd)
$configure_args["--topdir"] ||= $curdir