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Module: MakeMakefile

Relationships & Source Files
Defined in: lib/mkmf.rb

Overview

mkmf.rb is used by Ruby C extensions to generate a Makefile which will correctly compile and link the C extension to Ruby and a third-party library.

Constant Summary

Instance Method Summary

Instance Method Details

#check_signedness(type, headers = nil, opts = nil, &b)

Returns the signedness of the given type. You may optionally specify additional headers to search in for the type.

If the type is found and is a numeric type, a macro is passed as a preprocessor constant to the compiler using the type name, in uppercase, prepended with SIGNEDNESS_OF_, followed by the type name, followed by =X where “X” is positive integer if the type is unsigned and a negative integer if the type is signed.

For example, if size_t is defined as unsigned, then check_signedness('size_t') would return +1 and the SIGNEDNESS_OF_SIZE_T=1</code> preprocessor macro would be passed to the compiler. The SIGNEDNESS_OF_INT=-1 macro would be set for check_signedness('int')

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1355

def check_signedness(type, headers = nil, opts = nil, &b)
  typedef, member, prelude = typedef_expr(type, headers)
  signed = nil
  checking_for("signedness of #{type}", STRING_OR_FAILED_FORMAT) do
    signed = try_signedness(typedef, member, [prelude], opts, &b) or next nil
    $defs.push("-DSIGNEDNESS_OF_%s=%+d" % [type.tr_cpp, signed])
    signed < 0 ? "signed" : "unsigned"
  end
  signed
end

#check_sizeof(type, headers = nil, opts = "", &b)

Returns the size of the given type. You may optionally specify additional headers to search in for the type.

If found, a macro is passed as a preprocessor constant to the compiler using the type name, in uppercase, prepended with SIZEOF_, followed by the type name, followed by =X where “X” is the actual size.

For example, if check_sizeof('mystruct') returned 12, then the SIZEOF_MYSTRUCT=12 preprocessor macro would be passed to the compiler.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1326

def check_sizeof(type, headers = nil, opts = "", &b)
  typedef, member, prelude = typedef_expr(type, headers)
  prelude << "#{typedef} *rbcv_ptr_;\n"
  prelude = [prelude]
  expr = "sizeof((*rbcv_ptr_)#{"." << member if member})"
  fmt = STRING_OR_FAILED_FORMAT
  checking_for checking_message("size of #{type}", headers), fmt do
    if size = try_constant(expr, prelude, opts, &b)
      $defs.push(format("-DSIZEOF_%s=%s", type.tr_cpp, size))
      size
    end
  end
end

#convertible_int(type, headers = nil, opts = nil, &b)

Returns the convertible integer type of the given type. You may optionally specify additional headers to search in for the type. convertible means actually the same type, or typedef'd from the same type.

If the type is a integer type and the convertible type is found, the following macros are passed as preprocessor constants to the compiler using the type name, in uppercase.

  • TYPEOF_, followed by the type name, followed by =X where “X” is the found convertible type name.

  • TYP2NUM and NUM2TYP, where TYP is the type name in uppercase with replacing an _t suffix with “T”, followed by =X where “X” is the macro name to convert type to an Integer object, and vice versa.

For example, if foobar_t is defined as unsigned long, then convertible_int("foobar_t") would return “unsigned long”, and define these macros:

#define TYPEOF_FOOBAR_T unsigned long
#define FOOBART2NUM ULONG2NUM
#define NUM2FOOBART NUM2ULONG
[ GitHub ]

  
# File 'lib/mkmf.rb', line 1390

def convertible_int(type, headers = nil, opts = nil, &b)
  type, macname = *type
  checking_for("convertible type of #{type}", STRING_OR_FAILED_FORMAT) do
    if UNIVERSAL_INTS.include?(type)
      type
    else
      typedef, member, prelude = typedef_expr(type, headers, &b)
      if member
        prelude << "static rbcv_typedef_ rbcv_var;"
        compat = UNIVERSAL_INTS.find {|t|
          try_static_assert("sizeof(rbcv_var.#{member}) == sizeof(#{t})", [prelude], opts, &b)
        }
      else
        next unless signed = try_signedness(typedef, member, [prelude])
        u = "unsigned " if signed > 0
        prelude << "extern rbcv_typedef_ foo();"
        compat = UNIVERSAL_INTS.find {|t|
          try_compile([prelude, "extern #{u}#{t} foo();"].join("\n"), opts, :werror=>true, &b)
        }
      end
      if compat
        macname ||= type.sub(/_(?=t\z)/, '').tr_cpp
        conv = (compat == "long long" ? "LL" : compat.upcase)
        compat = "#{u}#{compat}"
        typename = type.tr_cpp
        $defs.push(format("-DSIZEOF_%s=SIZEOF_%s", typename, compat.tr_cpp))
        $defs.push(format("-DTYPEOF_%s=%s", typename, compat.quote))
        $defs.push(format("-DPRI_%s_PREFIX=PRI_%s_PREFIX", macname, conv))
        conv = (u ? "U" : "") + conv
        $defs.push(format("-D%s2NUM=%s2NUM", macname, conv))
        $defs.push(format("-DNUM2%s=NUM2%s", macname, conv))
        compat
      end
    end
  end
end

#create_header(header = "extconf.h")

Generates a header file consisting of the various macro definitions generated by other methods such as have_func and have_header. These are then wrapped in a custom #ifndef based on the header file name, which defaults to “extconf.h”.

For example:

# extconf.rb
require 'mkmf'
have_func('realpath')
have_header('sys/utime.h')
create_header
create_makefile('foo')

The above script would generate the following extconf.h file:

#ifndef EXTCONF_H
#define EXTCONF_H
#define HAVE_REALPATH 1
#define HAVE_SYS_UTIME_H 1
#endif

Given that the create_header method generates a file based on definitions set earlier in your extconf.rb file, you will probably want to make this one of the last methods you call in your script.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1681

def create_header(header = "extconf.h")
  message "creating %s\n", header
  sym = header.tr_cpp
  hdr = ["#ifndef #{sym}\n#define #{sym}\n"]
  for line in $defs
    case line
    when /^-D([^=]+)(?:=(.*))?/
      hdr << "#define #$1 #{$2 ? Shellwords.shellwords($2)[0].gsub(/(?=\t+)/, "\\\n") : 1}\n"
    when /^-U(.*)/
      hdr << "#undef #$1\n"
    end
  end
  hdr << "#endif\n"
  hdr = hdr.join("")
  log_src(hdr, "#{header} is")
  unless (IO.read(header) == hdr rescue false)
    open(header, "wb") do |hfile|
      hfile.write(hdr)
    end
  end
  $extconf_h = header
end

#create_makefile(target, srcprefix = nil)

Generates the Makefile for your extension, passing along any options and preprocessor constants that you may have generated through other methods.

The target name should correspond the name of the global function name defined within your C extension, minus the Init_. For example, if your C extension is defined as Init_foo, then your target would simply be “foo”.

If any “/” characters are present in the target name, only the last name is interpreted as the target name, and the rest are considered toplevel directory names, and the generated Makefile will be altered accordingly to follow that directory structure.

For example, if you pass “test/foo” as a target name, your extension will be installed under the “test” directory. This means that in order to load the file within a Ruby program later, that directory structure will have to be followed, e.g. require 'test/foo'.

The srcprefix should be used when your source files are not in the same directory as your build script. This will not only eliminate the need for you to manually copy the source files into the same directory as your build script, but it also sets the proper target_prefix in the generated Makefile.

Setting the target_prefix will, in turn, install the generated binary in a directory under your RbConfig::CONFIG['sitearchdir'] that mimics your local filesystem when you run make install.

For example, given the following file tree:

ext/
  extconf.rb
  test/
    foo.c

And given the following code:

create_makefile('test/foo', 'test')

That will set the target_prefix in the generated Makefile to “test”. That, in turn, will create the following file tree when installed via the make install command:

/path/to/ruby/sitearchdir/test/foo.so

It is recommended that you use this approach to generate your makefiles, instead of copying files around manually, because some third party libraries may depend on the target_prefix being set properly.

The srcprefix argument can be used to override the default source directory, i.e. the current directory. It is included as part of the VPATH and added to the list of INCFLAGS.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 2180

def create_makefile(target, srcprefix = nil)
  $target = target
  libpath = $DEFLIBPATH|$LIBPATH
  message "creating Makefile\n"
  MakeMakefile.rm_f "#{CONFTEST}*"
  if CONFIG["DLEXT"] == $OBJEXT
    for lib in libs = $libs.split
      lib.sub!(/-l(.*)/, %%"lib\\1.#{$LIBEXT}"%)
    end
    $defs.push(format("-DEXTLIB='%s'", libs.join(",")))
  end

  if target.include?('/')
    target_prefix, target = File.split(target)
    target_prefix[0,0] = '/'
  else
    target_prefix = ""
  end

  srcprefix ||= "$(srcdir)/#{srcprefix}".chomp('/')
  RbConfig.expand(srcdir = srcprefix.dup)

  ext = ".#{$OBJEXT}"
  orig_srcs = Dir[File.join(srcdir, "*.{#{SRC_EXT.join(%q{,})}}")].sort
  if not $objs
    srcs = $srcs || orig_srcs
    $objs = []
    objs = srcs.inject(Hash.new {[]}) {|h, f|
      h.key?(o = File.basename(f, ".*") << ext) or $objs << o
      h[o] <<= f
      h
    }
    unless objs.delete_if {|b, f| f.size == 1}.empty?
      dups = objs.sort.map {|b, f|
        "#{b[/.*\./]}{#{f.collect {|n| n[/([^.]+)\z/]}.join(',')}}"
      }
      abort "source files duplication - #{dups.join(", ")}"
    end
  else
    $objs.collect! {|o| File.basename(o, ".*") << ext} unless $OBJEXT == "o"
    srcs = $srcs || $objs.collect {|o| o.chomp(ext) << ".c"}
  end
  $srcs = srcs

  hdrs = Dir[File.join(srcdir, "*.{#{HDR_EXT.join(%q{,})}}")]

  target = nil if $objs.empty?

  if target and EXPORT_PREFIX
    if File.exist?(File.join(srcdir, target + '.def'))
      deffile = "$(srcdir)/$(TARGET).def"
      unless EXPORT_PREFIX.empty?
        makedef = %{$(RUBY) -pe "$$_.sub!(/^(?=\\w)/,'#{EXPORT_PREFIX}') unless 1../^EXPORTS$/i" #{deffile}}
      end
    else
      makedef = %{(echo EXPORTS && echo $(TARGET_ENTRY))}
    end
    if makedef
      $cleanfiles << '$(DEFFILE)'
      origdef = deffile
      deffile = "$(TARGET)-$(arch).def"
    end
  end
  origdef ||= ''

  if $extout and $INSTALLFILES
    $cleanfiles.concat($INSTALLFILES.collect {|files, dir|File.join(dir, files.sub(/\A\.\//, ''))})
    $distcleandirs.concat($INSTALLFILES.collect {|files, dir| dir})
  end

  if $extmk and $static
    $defs << "-DRUBY_EXPORT=1"
  end

  if $extmk and not $extconf_h
    create_header
  end

  libpath = libpathflag(libpath)

  dllib = target ? "$(TARGET).#{CONFIG['DLEXT']}" : ""
  staticlib = target ? "$(TARGET).#$LIBEXT" : ""
  mfile = open("Makefile", "wb")
  conf = configuration(srcprefix)
  conf = yield(conf) if block_given?
  mfile.puts(conf)
  mfile.print "
libpath = #{($DEFLIBPATH|$LIBPATH).join(" ")}
LIBPATH = #{libpath}
DEFFILE = #{deffile}

CLEANFILES = #{$cleanfiles.join(' ')}
DISTCLEANFILES = #{$distcleanfiles.join(' ')}
DISTCLEANDIRS = #{$distcleandirs.join(' ')}

extout = #{$extout && $extout.quote}
extout_prefix = #{$extout_prefix}
target_prefix = #{target_prefix}
LOCAL_LIBS = #{$LOCAL_LIBS}
LIBS = #{$LIBRUBYARG} #{$libs} #{$LIBS}
ORIG_SRCS = #{orig_srcs.collect(&File.method(:basename)).join(' ')}
SRCS = $(ORIG_SRCS) #{(srcs - orig_srcs).collect(&File.method(:basename)).join(' ')}
OBJS = #{$objs.join(" ")}
HDRS = #{hdrs.map{|h| '$(srcdir)/' + File.basename(h)}.join(' ')}
TARGET = #{target}
TARGET_NAME = #{target && target[/\A\w+/]}
TARGET_ENTRY = #{EXPORT_PREFIX || ''}Init_$(TARGET_NAME)
DLLIB = #{dllib}
EXTSTATIC = #{$static || ""}
STATIC_LIB = #{staticlib unless $static.nil?}
#{!$extout && defined?($installed_list) ? "INSTALLED_LIST = #{$installed_list}\n" : ""}
TIMESTAMP_DIR = #{$extout ? '$(extout)/.timestamp' : '.'}
" #"
  # TODO: fixme
  install_dirs.each {|d| mfile.print("%-14s= %s\n" % d) if /^[[:upper:]]/ =~ d[0]}
  n = ($extout ? '$(RUBYARCHDIR)/' : '') + '$(TARGET)'
  mfile.print "
TARGET_SO     = #{($extout ? '$(RUBYARCHDIR)/' : '')}$(DLLIB)
CLEANLIBS     = #{n}.#{CONFIG['DLEXT']} #{config_string('cleanlibs') {|t| t.gsub(/\$\*/) {n}}}
CLEANOBJS     = *.#{$OBJEXT} #{config_string('cleanobjs') {|t| t.gsub(/\$\*/, "$(TARGET)#{deffile ? '-$(arch)': ''}")} if target} *.bak

all:    #{$extout ? "install" : target ? "$(DLLIB)" : "Makefile"}
static: #{$extmk && !$static ? "all" : "$(STATIC_LIB)#{$extout ? " install-rb" : ""}"}
.PHONY: all install static install-so install-rb
.PHONY: clean clean-so clean-static clean-rb
"
  mfile.print CLEANINGS
  fsep = config_string('BUILD_FILE_SEPARATOR') {|s| s unless s == "/"}
  if fsep
    sep = ":/=#{fsep}"
    fseprepl = proc {|s|
      s = s.gsub("/", fsep)
      s = s.gsub(/(\$\(\w+)(\))/) {$1sep$2}
      s.gsub(/(\$\{\w+)(\})/) {$1sep$2}
    }
    rsep = ":#{fsep}=/"
  else
    fseprepl = proc {|s| s}
    sep = ""
    rsep = ""
  end
  dirs = []
  mfile.print "install: install-so install-rb\n\n"
  sodir = (dir = "$(RUBYARCHDIR)").dup
  mfile.print("install-so: ")
  if target
    f = "$(DLLIB)"
    dest = "#{dir}/#{f}"
    stamp = timestamp_file(dir, target_prefix)
    if $extout
      mfile.puts dest
      mfile.print "clean-so::\n"
      mfile.print "\t-$(Q)$(RM) #{fseprepl[dest]} #{fseprepl[stamp]}\n"
      mfile.print "\t-$(Q)$(RMDIRS) #{fseprepl[dir]}#{$ignore_error}\n"
    else
      mfile.print "#{f} #{stamp}\n"
      mfile.print "\t$(INSTALL_PROG) #{fseprepl[f]} #{dir}\n"
      if defined?($installed_list)
        mfile.print "\t@echo #{dir}/#{File.basename(f)}>>$(INSTALLED_LIST)\n"
      end
    end
    mfile.print "clean-static::\n"
    mfile.print "\t-$(Q)$(RM) $(STATIC_LIB)\n"
  else
    mfile.puts "Makefile"
  end
  mfile.print("install-rb: pre-install-rb install-rb-default\n")
  mfile.print("install-rb-default: pre-install-rb-default\n")
  mfile.print("pre-install-rb: Makefile\n")
  mfile.print("pre-install-rb-default: Makefile\n")
  for sfx, i in [["-default", [["lib/**/*.rb", "$(RUBYLIBDIR)", "lib"]]], ["", $INSTALLFILES]]
    files = install_files(mfile, i, nil, srcprefix) or next
    for dir, *files in files
      unless dirs.include?(dir)
        dirs << dir
        mfile.print "pre-install-rb#{sfx}: #{timestamp_file(dir, target_prefix)}\n"
      end
      for f in files
        dest = "#{dir}/#{File.basename(f)}"
        mfile.print("install-rb#{sfx}: #{dest}\n")
        mfile.print("#{dest}: #{f} #{timestamp_file(dir, target_prefix)}\n")
        mfile.print("\t$(Q) $(#{$extout ? 'COPY' : 'INSTALL_DATA'}) #{f} $(@D)\n")
        if defined?($installed_list) and !$extout
          mfile.print("\t@echo #{dest}>>$(INSTALLED_LIST)\n")
        end
        if $extout
          mfile.print("clean-rb#{sfx}::\n")
          mfile.print("\t-$(Q)$(RM) #{fseprepl[dest]}\n")
        end
      end
    end
    mfile.print "pre-install-rb#{sfx}:\n"
    if files.empty?
      mfile.print("\t@$(NULLCMD)\n")
    else
      mfile.print("\t$(ECHO) installing#{sfx.sub(/^-/, " ")} #{target} libraries\n")
    end
    if $extout
      dirs.uniq!
      unless dirs.empty?
        mfile.print("clean-rb#{sfx}::\n")
        for dir in dirs.sort_by {|d| -d.count('/')}
          stamp = timestamp_file(dir, target_prefix)
          mfile.print("\t-$(Q)$(RM) #{fseprepl[stamp]}\n")
          mfile.print("\t-$(Q)$(RMDIRS) #{fseprepl[dir]}#{$ignore_error}\n")
        end
      end
    end
  end
  dirs.unshift(sodir) if target and !dirs.include?(sodir)
  dirs.each do |d|
    t = timestamp_file(d, target_prefix)
    mfile.print "#{t}:\n\t$(Q) $(MAKEDIRS) $(@D) #{d}\n\t$(Q) $(TOUCH) $@\n"
  end

  mfile.print <<-SITEINSTALL

site-install: site-install-so site-install-rb
site-install-so: install-so
site-install-rb: install-rb

  SITEINSTALL

  return unless target

  mfile.puts SRC_EXT.collect {|e| ".path.#{e} = $(VPATH)"} if $nmake == ?b
  mfile.print ".SUFFIXES: .#{(SRC_EXT + [$OBJEXT, $ASMEXT]).compact.join(' .')}\n"
  mfile.print "\n"

  compile_command = "\n\t$(ECHO) compiling $(<#{rsep})\n\t$(Q) %s\n\n"
  command = compile_command % COMPILE_CXX
  asm_command = compile_command.sub(/compiling/, 'translating') % ASSEMBLE_CXX
  CXX_EXT.each do |e|
    each_compile_rules do |rule|
      mfile.printf(rule, e, $OBJEXT)
      mfile.print(command)
      mfile.printf(rule, e, $ASMEXT)
      mfile.print(asm_command)
    end
  end
  command = compile_command % COMPILE_C
  asm_command = compile_command.sub(/compiling/, 'translating') % ASSEMBLE_C
  C_EXT.each do |e|
    each_compile_rules do |rule|
      mfile.printf(rule, e, $OBJEXT)
      mfile.print(command)
      mfile.printf(rule, e, $ASMEXT)
      mfile.print(asm_command)
    end
  end

  mfile.print "$(RUBYARCHDIR)/" if $extout
  mfile.print "$(DLLIB): "
  mfile.print "$(DEFFILE) " if makedef
  mfile.print "$(OBJS) Makefile"
  mfile.print " #{timestamp_file('$(RUBYARCHDIR)', target_prefix)}" if $extout
  mfile.print "\n"
  mfile.print "\t$(ECHO) linking shared-object #{target_prefix.sub(/\A\/(.*)/, '\1/')}$(DLLIB)\n"
  mfile.print "\t-$(Q)$(RM) $(@#{sep})\n"
  link_so = LINK_SO.gsub(/^/, "\t$(Q) ")
  if srcs.any?(&%r"\.(?:#{CXX_EXT.join('|')})\z".method(:===))
    link_so = link_so.sub(/\bLDSHARED\b/, '\&XX')
  end
  mfile.print link_so, "\n\n"
  unless $static.nil?
    mfile.print "$(STATIC_LIB): $(OBJS)\n\t-$(Q)$(RM) $(@#{sep})\n\t"
    mfile.print "$(ECHO) linking static-library $(@#{rsep})\n\t$(Q) "
    mfile.print "$(AR) #{config_string('ARFLAGS') || 'cru '}$@ $(OBJS)"
    config_string('RANLIB') do |ranlib|
      mfile.print "\n\t-$(Q)#{ranlib} $(@) 2> /dev/null || true"
    end
  end
  mfile.print "\n\n"
  if makedef
    mfile.print "$(DEFFILE): #{origdef}\n"
    mfile.print "\t$(ECHO) generating $(@#{rsep})\n"
    mfile.print "\t$(Q) #{makedef} > $@\n\n"
  end

  depend = File.join(srcdir, "depend")
  if File.exist?(depend)
    mfile.print("###\n", *depend_rules(File.read(depend)))
  else
    mfile.print "$(OBJS): $(HDRS) $(ruby_headers)\n"
  end

  $makefile_created = true
ensure
  mfile.close if mfile
end

#depend_rules(depend)

Processes the data contents of the “depend” file. Each line of this file is expected to be a file name.

Returns the output of findings, in Makefile format.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 2067

def depend_rules(depend)
  suffixes = []
  depout = []
  cont = implicit = nil
  impconv = proc do
    each_compile_rules {|rule| depout << (rule % implicit[0]) << implicit[1]}
    implicit = nil
  end
  ruleconv = proc do |line|
    if implicit
      if /\A\t/ =~ line
        implicit[1] << line
        next
      else
        impconv[]
      end
    end
    if m = /\A\.(\w)\.(\w)(?:\s*:)/.match(line)
      suffixes << m[1] << m[2]
      implicit = [[m[1], m[2]], [m.post_match]]
      next
    elsif RULE_SUBST and /\A(?!\s*\w+\s*=)[$\w][^#]*:/ =~ line
      line.sub!(/\s*\#.*$/, '')
      comment = $&
      line.gsub!(%r"(\s)(?!\.)([^$(){}=:\s\\,])(?=\s|\z)") {$1 + RULE_SUBST % $2}
      line = line.chomp + comment + "\n" if comment
    end
    depout << line
  end
  depend.each_line do |line|
    line.gsub!(/\.o\b/, ".#{$OBJEXT}")
    line.gsub!(/\{\$\(VPATH\)\}/, "") unless $nmake
    line.gsub!(/\$\((?:hdr|top)dir\)\/config.h/, $config_h)
    line.gsub!(%r"\$\(hdrdir\)/(?!ruby(?![^:;/\s]))(?=[-\w]+\.h)", '\&ruby/')
    if $nmake && /\A\s*\$\(RM|COPY\)/ =~ line
      line.gsub!(%r"[-\w\./]{2,}"){$&.tr("/", "\\")}
      line.gsub!(/(\$\((?!RM|COPY)[^:)]+)(?=\))/, '\1:/=\\')
    end
    if /(?:^|[^\\])(?:\\\\)*\\$/ =~ line
      (cont ||= []) << line
      next
    elsif cont
      line = (cont << line).join
      cont = nil
    end
    ruleconv.call(line)
  end
  if cont
    ruleconv.call(cont.join)
  elsif implicit
    impconv.call
  end
  unless suffixes.empty?
    depout.unshift(".SUFFIXES: ." + suffixes.uniq.join(" .") + "\n\n")
  end
  depout.unshift("$(OBJS): $(RUBY_EXTCONF_H)\n\n") if $extconf_h
  depout.flatten!
  depout
end

#dir_config(target) #dir_config(target, prefix) #dir_config(target, idefault, ldefault)

Sets a target name that the user can then use to configure various “with” options with on the command line by using that name. For example, if the target is set to “foo”, then the user could use the --with-foo-dir=prefix, --with-foo-include=dir and --with-foo-lib=dir command line options to tell where to search for header/library files.

You may pass along additional parameters to specify default values. If one is given it is taken as default prefix, and if two are given they are taken as “include” and “lib” defaults in that order.

In any case, the return value will be an array of determined “include” and “lib” directories, either of which can be nil if no corresponding command line option is given when no default value is specified.

Note that dir_config only adds to the list of places to search for libraries and include files. It does not link the libraries into your application.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1731

def dir_config(target, idefault=nil, ldefault=nil)
  if dir = with_config(target + "-dir", (idefault unless ldefault))
    defaults = Array === dir ? dir : dir.split(File::PATH_SEPARATOR)
    idefault = ldefault = nil
  end

  idir = with_config(target + "-include", idefault)
  $arg_config.last[1] ||= "${#{target}-dir}/include"
  ldir = with_config(target + "-lib", ldefault)
  $arg_config.last[1] ||= "${#{target}-dir}/#{_libdir_basename}"

  idirs = idir ? Array === idir ? idir.dup : idir.split(File::PATH_SEPARATOR) : []
  if defaults
    idirs.concat(defaults.collect {|d| d + "/include"})
    idir = ([idir] + idirs).compact.join(File::PATH_SEPARATOR)
  end
  unless idirs.empty?
    idirs.collect! {|d| "-I" + d}
    idirs -= Shellwords.shellwords($CPPFLAGS)
    unless idirs.empty?
      $CPPFLAGS = (idirs.quote << $CPPFLAGS).join(" ")
    end
  end

  ldirs = ldir ? Array === ldir ? ldir.dup : ldir.split(File::PATH_SEPARATOR) : []
  if defaults
    ldirs.concat(defaults.collect {|d| "#{d}/#{_libdir_basename}"})
    ldir = ([ldir] + ldirs).compact.join(File::PATH_SEPARATOR)
  end
  $LIBPATH = ldirs | $LIBPATH

  [idir, ldir]
end

#dummy_makefile(srcdir)

creates a stub Makefile.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 2037

def dummy_makefile(srcdir)
  configuration(srcdir) << <<RULES << CLEANINGS
CLEANFILES = #{$cleanfiles.join(' ')}
DISTCLEANFILES = #{$distcleanfiles.join(' ')}

all install static install-so install-rb: Makefile
.PHONY: all install static install-so install-rb
.PHONY: clean clean-so clean-static clean-rb

RULES
end

#enable_config(config, default = nil)

Tests for the presence of an --enable-config or --disable-config option. Returns true if the enable option is given, false if the disable option is given, and the default value otherwise.

This can be useful for adding custom definitions, such as debug information.

Example:

if enable_config("debug")
   $defs.push("-DOSSL_DEBUG") unless $defs.include? "-DOSSL_DEBUG"
end
[ GitHub ]

  
# File 'lib/mkmf.rb', line 1643

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

#find_executable(bin, path = nil)

Searches for the executable bin on path. The default path is your PATH environment variable. If that isn't defined, it will resort to searching /usr/local/bin, /usr/ucb, /usr/bin and /bin.

If found, it will return the full path, including the executable name, of where it was found.

Note that this method does not actually affect the generated Makefile.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1573

def find_executable(bin, path = nil)
  checking_for checking_message(bin, path) do
    find_executable0(bin, path)
  end
end

#find_header(header, *paths)

Instructs mkmf to search for the given header in any of the paths provided, and returns whether or not it was found in those paths.

If the header is found then the path it was found on is added to the list of included directories that are sent to the compiler (via the -I switch).

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1140

def find_header(header, *paths)
  message = checking_message(header, paths)
  header = cpp_include(header)
  checking_for message do
    if try_header(header)
      true
    else
      found = false
      paths.each do |dir|
        opt = "-I#{dir}".quote
        if try_header(header, opt)
          $INCFLAGS << " " << opt
          found = true
          break
        end
      end
      found
    end
  end
end

#find_library(lib, func, *paths, &b)

Returns whether or not the entry point func can be found within the library lib in one of the paths specified, where paths is an array of strings. If func is nil , then the main() function is used as the entry point.

If lib is found, then the path it was found on is added to the list of library paths searched and linked against.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1015

def find_library(lib, func, *paths, &b)
  func = "main" if !func or func.empty?
  lib = with_config(lib+'lib', lib)
  paths = paths.collect {|path| path.split(File::PATH_SEPARATOR)}.flatten
  checking_for checking_message(func.funcall_style, LIBARG%lib) do
    libpath = $LIBPATH
    libs = append_library($libs, lib)
    begin
      until r = try_func(func, libs, &b) or paths.empty?
        $LIBPATH = libpath | [paths.shift]
      end
      if r
        $libs = libs
        libpath = nil
      end
    ensure
      $LIBPATH = libpath if libpath
    end
    r
  end
end

#find_type(type, opt, *headers, &b)

Returns where the static type type is defined.

You may also pass additional flags to opt which are then passed along to the compiler.

See also #have_type.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1237

def find_type(type, opt, *headers, &b)
  opt ||= ""
  fmt = "not found"
  def fmt.%(x)
    x ? x.respond_to?(:join) ? x.join(",") : x : self
  end
  checking_for checking_message(type, nil, opt), fmt do
    headers.find do |h|
      try_type(type, h, opt, &b)
    end
  end
end

#have_const(const, headers = nil, opt = "", &b)

Returns whether or not the constant const is defined. You may optionally pass the type of const as [const, type], such as:

have_const(%w[PTHREAD_MUTEX_INITIALIZER pthread_mutex_t], "pthread.h")

You may also pass additional headers to check against in addition to the common header files, and additional flags to opt which are then passed along to the compiler.

If found, a macro is passed as a preprocessor constant to the compiler using the type name, in uppercase, prepended with HAVE_CONST_.

For example, if have_const('foo') returned true, then the HAVE_CONST_FOO preprocessor macro would be passed to the compiler.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1285

def have_const(const, headers = nil, opt = "", &b)
  checking_for checking_message([*const].compact.join(' '), headers, opt) do
    try_const(const, headers, opt, &b)
  end
end

#have_framework(fw, &b)

Returns whether or not the given framework can be found on your system. If found, a macro is passed as a preprocessor constant to the compiler using the framework name, in uppercase, prepended with HAVE_FRAMEWORK_.

For example, if have_framework('Ruby') returned true, then the HAVE_FRAMEWORK_RUBY preprocessor macro would be passed to the compiler.

If fw is a pair of the framework name and its header file name that header file is checked, instead of the normally used header file which is named same as the framework.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1111

def have_framework(fw, &b)
  if Array === fw
    fw, header = *fw
  else
    header = "#{fw}.h"
  end
  checking_for fw do
    src = cpp_include("#{fw}/#{header}") << "\n" "int main(void){return 0;}"
    opt = " -framework #{fw}"
    if try_link(src, opt, &b) or (objc = try_link(src, "-ObjC#{opt}", &b))
      $defs.push(format("-DHAVE_FRAMEWORK_%s", fw.tr_cpp))
      # TODO: non-worse way than this hack, to get rid of separating
      # option and its argument.
      $LDFLAGS << " -ObjC" if objc and /(\A|\s)-ObjC(\s|\z)/ !~ $LDFLAGS
      $LIBS << opt
      true
    else
      false
    end
  end
end

#have_func(func, headers = nil, opt = "", &b)

Returns whether or not the function func can be found in the common header files, or within any headers that you provide. If found, a macro is passed as a preprocessor constant to the compiler using the function name, in uppercase, prepended with HAVE_.

To check functions in an additional library, you need to check that library first using have_library(). The func shall be either mere function name or function name with arguments.

For example, if have_func('foo') returned true, then the HAVE_FOO preprocessor macro would be passed to the compiler.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1049

def have_func(func, headers = nil, opt = "", &b)
  checking_for checking_message(func.funcall_style, headers, opt) do
    if try_func(func, $libs, headers, opt, &b)
      $defs << "-DHAVE_#{func.sans_arguments.tr_cpp}"
      true
    else
      false
    end
  end
end

#have_header(header, preheaders = nil, opt = "", &b)

Returns whether or not the given header file can be found on your system. If found, a macro is passed as a preprocessor constant to the compiler using the header file name, in uppercase, prepended with HAVE_.

For example, if have_header('foo.h') returned true, then the HAVE_FOO_H preprocessor macro would be passed to the compiler.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1089

def have_header(header, preheaders = nil, opt = "", &b)
  checking_for header do
    if try_header(cpp_include(preheaders)+cpp_include(header), opt, &b)
      $defs.push(format("-DHAVE_%s", header.tr_cpp))
      true
    else
      false
    end
  end
end

#have_library(lib, func = nil, headers = nil, opt = "", &b)

Returns whether or not the given entry point func can be found within lib. If func is nil, the main() entry point is used by default. If found, it adds the library to list of libraries to be used when linking your extension.

If headers are provided, it will include those header files as the header files it looks in when searching for func.

The real name of the library to be linked can be altered by --with-FOOlib configuration option.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 989

def have_library(lib, func = nil, headers = nil, opt = "", &b)
  func = "main" if !func or func.empty?
  lib = with_config(lib+'lib', lib)
  checking_for checking_message(func.funcall_style, LIBARG%lib, opt) do
    if COMMON_LIBS.include?(lib)
      true
    else
      libs = append_library($libs, lib)
      if try_func(func, libs, headers, opt, &b)
        $libs = libs
        true
      else
        false
      end
    end
  end
end

#have_macro(macro, headers = nil, opt = "", &b)

Returns whether or not macro is defined either in the common header files or within any headers you provide.

Any options you pass to opt are passed along to the compiler.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 972

def have_macro(macro, headers = nil, opt = "", &b)
  checking_for checking_message(macro, headers, opt) do
    macro_defined?(macro, cpp_include(headers), opt, &b)
  end
end

#have_struct_member(type, member, headers = nil, opt = "", &b)

Returns whether or not the struct of type type contains member. If it does not, or the struct type can't be found, then false is returned. You may optionally specify additional headers in which to look for the struct (in addition to the common header files).

If found, a macro is passed as a preprocessor constant to the compiler using the type name and the member name, in uppercase, prepended with HAVE_.

For example, if have_struct_member('struct foo', 'bar') returned true, then the HAVE_STRUCT_FOO_BAR preprocessor macro would be passed to the compiler.

HAVE_ST_BAR is also defined for backward compatibility.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1176

def have_struct_member(type, member, headers = nil, opt = "", &b)
  checking_for checking_message("#{type}.#{member}", headers) do
    if try_compile(<<"SRC", opt, &b)
#{cpp_include(headers)}
/*top*/
int s = (char *)&((#{type}*)0)->#{member} - (char *)0;
#{MAIN_DOES_NOTHING}
SRC
      $defs.push(format("-DHAVE_%s_%s", type.tr_cpp, member.tr_cpp))
      $defs.push(format("-DHAVE_ST_%s", member.tr_cpp)) # backward compatibility
      true
    else
      false
    end
  end
end

#have_type(type, headers = nil, opt = "", &b)

Returns whether or not the static type type is defined. You may optionally pass additional headers to check against in addition to the common header files.

You may also pass additional flags to opt which are then passed along to the compiler.

If found, a macro is passed as a preprocessor constant to the compiler using the type name, in uppercase, prepended with HAVE_TYPE_.

For example, if have_type('foo') returned true, then the HAVE_TYPE_FOO preprocessor macro would be passed to the compiler.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1224

def have_type(type, headers = nil, opt = "", &b)
  checking_for checking_message(type, headers, opt) do
    try_type(type, headers, opt, &b)
  end
end

#have_var(var, headers = nil, opt = "", &b)

Returns whether or not the variable var can be found in the common header files, or within any headers that you provide. If found, a macro is passed as a preprocessor constant to the compiler using the variable name, in uppercase, prepended with HAVE_.

To check variables in an additional library, you need to check that library first using have_library().

For example, if have_var('foo') returned true, then the HAVE_FOO preprocessor macro would be passed to the compiler.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1071

def have_var(var, headers = nil, opt = "", &b)
  checking_for checking_message(var, headers, opt) do
    if try_var(var, headers, opt, &b)
      $defs.push(format("-DHAVE_%s", var.tr_cpp))
      true
    else
      false
    end
  end
end

#pkg_config(pkg, option = nil)

Returns compile/link information about an installed library in a tuple of [cflags, ldflags, libs], by using the command found first in the following commands:

  1. If --with-{pkg}-config={command} is given via command line option: {command} {option}

  2. {pkg}-config {option}

  3. pkg-config {option} {pkg}

Where option is, for instance, --cflags.

The values obtained are appended to $CFLAGS, $LDFLAGS and $libs.

If an option argument is given, the config command is invoked with the option and a stripped output string is returned without modifying any of the global values mentioned above.

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1784

def pkg_config(pkg, option=nil)
  if pkgconfig = with_config("#{pkg}-config") and find_executable0(pkgconfig)
    # iff package specific config command is given
  elsif ($PKGCONFIG ||=
         (pkgconfig = with_config("pkg-config", ("pkg-config" unless CROSS_COMPILING))) &&
         find_executable0(pkgconfig) && pkgconfig) and
      xsystem("#{$PKGCONFIG} --exists #{pkg}")
    # default to pkg-config command
    pkgconfig = $PKGCONFIG
    get = proc {|opt|
      opt = xpopen("#{$PKGCONFIG} --#{opt} #{pkg}", err:[:child, :out], &:read)
      Logging.open {puts opt.each_line.map{|s|"=> #{s.inspect}"}}
      opt.strip if $?.success?
    }
  elsif find_executable0(pkgconfig = "#{pkg}-config")
    # default to package specific config command, as a last resort.
  else
    pkgconfig = nil
  end
  if pkgconfig
    get ||= proc {|opt|
      opt = xpopen("#{pkgconfig} --#{opt}", err:[:child, :out], &:read)
      Logging.open {puts opt.each_line.map{|s|"=> #{s.inspect}"}}
      opt.strip if $?.success?
    }
  end
  orig_ldflags = $LDFLAGS
  if get and option
    get[option]
  elsif get and try_ldflags(ldflags = get['libs'])
    if incflags = get['cflags-only-I']
      $INCFLAGS << " " << incflags
      cflags = get['cflags-only-other']
    else
      cflags = get['cflags']
    end
    libs = get['libs-only-l']
    if cflags
      $CFLAGS += " " << cflags
      $CXXFLAGS += " " << cflags
    end
    if libs
      ldflags = (Shellwords.shellwords(ldflags) - Shellwords.shellwords(libs)).quote.join(" ")
    else
      libs, ldflags = Shellwords.shellwords(ldflags).partition {|s| s =~ /-l([^ ]+)/ }.map {|l|l.quote.join(" ")}
    end
    $libs += " " << libs

    $LDFLAGS = [orig_ldflags, ldflags].join(' ')
    Logging::message "package configuration for %s\n", pkg
    Logging::message "cflags: %s\nldflags: %s\nlibs: %s\n\n",
                     cflags, ldflags, libs
    [cflags, ldflags, libs]
  else
    Logging::message "package configuration for %s is not found\n", pkg
    nil
  end
end

#try_const(const, headers = nil, opt = "", &b)

Returns whether or not the constant const is defined.

See also #have_const

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1254

def try_const(const, headers = nil, opt = "", &b)
  const, type = *const
  if try_compile(<<"SRC", opt, &b)
#{cpp_include(headers)}
/*top*/
typedef #{type || 'int'} conftest_type;
conftest_type conftestval = #{type ? '' : '(int)'}#{const};
SRC
    $defs.push(format("-DHAVE_CONST_%s", const.tr_cpp))
    true
  else
    false
  end
end

#try_type(type, headers = nil, opt = "", &b)

Returns whether or not the static type type is defined.

See also #have_type

[ GitHub ]

  
# File 'lib/mkmf.rb', line 1197

def try_type(type, headers = nil, opt = "", &b)
  if try_compile(<<"SRC", opt, &b)
#{cpp_include(headers)}
/*top*/
typedef #{type} conftest_type;
int conftestval[sizeof(conftest_type)?1:-1];
SRC
    $defs.push(format("-DHAVE_TYPE_%s", type.tr_cpp))
    true
  else
    false
  end
end

#with_config(config, default = nil)

Tests for the presence of a --with-config or --without-config option. Returns true if the with option is given, false if the without option is given, and the default value otherwise.

This can be useful for adding custom definitions, such as debug information.

Example:

if with_config("debug")
   $defs.push("-DOSSL_DEBUG") unless $defs.include? "-DOSSL_DEBUG"
end
[ GitHub ]

  
# File 'lib/mkmf.rb', line 1608

def with_config(config, default=nil)
  config = config.sub(/^--with[-_]/, '')
  val = arg_config("--with-"+config) do
    if arg_config("--without-"+config)
      false
    elsif block_given?
      yield(config, default)
    else
      break default
    end
  end
  case val
  when "yes"
    true
  when "no"
    false
  else
    val
  end
end