Top Level Namespace

Defined Under Namespace

Modules: Nokogiri, XSD

Constant Summary collapse

PACKAGE_ROOT_DIR =

helpful constants

File.expand_path(File.join(File.dirname(__FILE__), "..", ".."))
REQUIRED_LIBXML_VERSION =
"2.6.21"
"2.9.3"
REQUIRED_MINI_PORTILE_VERSION =

keep this version in sync with the one in the gemspec

"~> 2.8.2"
REQUIRED_PKG_CONFIG_VERSION =
"~> 1.1"
OTHER_LIBRARY_VERSIONS =

Keep track of what versions of what libraries we build against

{}
NOKOGIRI_HELP_MESSAGE =
<<~HELP
  USAGE: ruby #{$PROGRAM_NAME} [options]

    Flags that are always valid:

      --use-system-libraries
      --enable-system-libraries
          Use system libraries instead of building and using the packaged libraries.

      --disable-system-libraries
          Use the packaged libraries, and ignore the system libraries. This is the default on most
          platforms, and overrides `--use-system-libraries` and the environment variable
          `NOKOGIRI_USE_SYSTEM_LIBRARIES`.

      --disable-clean
          Do not clean out intermediate files after successful build.

      --prevent-strip
          Take steps to prevent stripping the symbol table and debugging info from the shared
          library, potentially overriding RbConfig's CFLAGS/LDFLAGS/DLDFLAGS.


    Flags only used when using system libraries:

      General:

        --with-opt-dir=DIRECTORY
            Look for headers and libraries in DIRECTORY.

        --with-opt-lib=DIRECTORY
            Look for libraries in DIRECTORY.

        --with-opt-include=DIRECTORY
            Look for headers in DIRECTORY.


      Related to zlib:

        --with-zlib-dir=DIRECTORY
            Look for zlib headers and library in DIRECTORY.

        --with-zlib-lib=DIRECTORY
            Look for zlib library in DIRECTORY.

        --with-zlib-include=DIRECTORY
            Look for zlib headers in DIRECTORY.


      Related to iconv:

        --with-iconv-dir=DIRECTORY
            Look for iconv headers and library in DIRECTORY.

        --with-iconv-lib=DIRECTORY
            Look for iconv library in DIRECTORY.

        --with-iconv-include=DIRECTORY
            Look for iconv headers in DIRECTORY.


      Related to libxml2:

        --with-xml2-dir=DIRECTORY
            Look for xml2 headers and library in DIRECTORY.

        --with-xml2-lib=DIRECTORY
            Look for xml2 library in DIRECTORY.

        --with-xml2-include=DIRECTORY
            Look for xml2 headers in DIRECTORY.

        --with-xml2-source-dir=DIRECTORY
            (dev only) Build libxml2 from the source code in DIRECTORY


      Related to libxslt:

        --with-xslt-dir=DIRECTORY
            Look for xslt headers and library in DIRECTORY.

        --with-xslt-lib=DIRECTORY
            Look for xslt library in DIRECTORY.

        --with-xslt-include=DIRECTORY
            Look for xslt headers in DIRECTORY.

        --with-xslt-source-dir=DIRECTORY
            (dev only) Build libxslt from the source code in DIRECTORY


      Related to libexslt:

        --with-exslt-dir=DIRECTORY
            Look for exslt headers and library in DIRECTORY.

        --with-exslt-lib=DIRECTORY
            Look for exslt library in DIRECTORY.

        --with-exslt-include=DIRECTORY
            Look for exslt headers in DIRECTORY.


    Flags only used when building and using the packaged libraries:

      --disable-static
          Do not statically link packaged libraries, instead use shared libraries.

      --enable-cross-build
          Enable cross-build mode. (You probably do not want to set this manually.)


    Environment variables used:

      NOKOGIRI_USE_SYSTEM_LIBRARIES
          Equivalent to `--enable-system-libraries` when set, even if nil or blank.

      CC
          Use this path to invoke the compiler instead of `RbConfig::CONFIG['CC']`

      CPPFLAGS
          If this string is accepted by the C preprocessor, add it to the flags passed to the C preprocessor

      CFLAGS
          If this string is accepted by the compiler, add it to the flags passed to the compiler

      LDFLAGS
          If this string is accepted by the linker, add it to the flags passed to the linker

      LIBS
          Add this string to the flags passed to the linker
HELP
LOCAL_PACKAGE_RESPONSE =
Object.new

Instance Method Summary collapse

Instance Method Details

#abort_could_not_find_library(lib) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 309

def abort_could_not_find_library(lib)
  callers = caller(1..2).join("\n")
  abort("-----\n#{callers}\n#{lib} is missing. Please locate mkmf.log to investigate how it is failing.\n-----")
end

#aix?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 194

def aix?
  RbConfig::CONFIG["target_os"].include?("aix")
end

#chdir_for_build(&block) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 314

def chdir_for_build(&block)
  # When using rake-compiler-dock on Windows, the underlying Virtualbox shared
  # folders don't support symlinks, but libiconv expects it for a build on
  # Linux. We work around this limitation by using the temp dir for cooking.
  build_dir = /mingw|mswin|cygwin/.match?(ENV["RCD_HOST_RUBY_PLATFORM"].to_s) ? "/tmp" : "."
  Dir.chdir(build_dir, &block)
end

#concat_flags(*args) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 206

def concat_flags(*args)
  args.compact.join(" ")
end

#config_clean?Boolean

utility functions

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 159

def config_clean?
  enable_config("clean", true)
end

#config_cross_build?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 168

def config_cross_build?
  enable_config("cross-build")
end

#config_static?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 163

def config_static?
  default_static = !truffle?
  enable_config("static", default_static)
end

#config_system_libraries?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 172

def config_system_libraries?
  enable_config("system-libraries", ENV.key?("NOKOGIRI_USE_SYSTEM_LIBRARIES")) do |_, default|
    arg_config("--use-system-libraries", default)
  end
end

#copy_packaged_libraries_headers(to_path:, from_recipes:) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 547

def copy_packaged_libraries_headers(to_path:, from_recipes:)
  FileUtils.rm_rf(to_path, secure: true)
  FileUtils.mkdir(to_path)
  from_recipes.each do |recipe|
    FileUtils.cp_r(Dir[File.join(recipe.path, "include/*")], to_path)
  end
end

#darwin?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 186

def darwin?
  RbConfig::CONFIG["target_os"].include?("darwin")
end

#do_cleanObject



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# File 'ext/nokogiri/extconf.rb', line 560

def do_clean
  root = Pathname(PACKAGE_ROOT_DIR)
  pwd  = Pathname(Dir.pwd)

  # Skip if this is a development work tree
  unless (root + ".git").exist?
    message("Cleaning files only used during build.\n")

    # (root + 'tmp') cannot be removed at this stage because
    # nokogiri.so is yet to be copied to lib.

    # clean the ports build directory
    Pathname.glob(pwd.join("tmp", "*", "ports")) do |dir|
      FileUtils.rm_rf(dir, verbose: true)
    end

    if config_static?
      # ports installation can be safely removed if statically linked.
      FileUtils.rm_rf(root + "ports", verbose: true)
    else
      FileUtils.rm_rf(root + "ports" + "archives", verbose: true)
    end
  end

  exit!(0)
end

#do_helpObject



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# File 'ext/nokogiri/extconf.rb', line 555

def do_help
  print(NOKOGIRI_HELP_MESSAGE)
  exit!(0)
end

#ensure_func(func, headers = nil) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 298

def ensure_func(func, headers = nil)
  have_func(func, headers) || abort_could_not_find_library(func)
end

#ensure_package_configuration(opt: nil, pc: nil, lib:, func:, headers:) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 293

def ensure_package_configuration(opt: nil, pc: nil, lib:, func:, headers:)
  have_package_configuration(opt: opt, pc: pc, lib: lib, func: func, headers: headers) ||
    abort_could_not_find_library(lib)
end

#gnome_sourceObject



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# File 'ext/nokogiri/extconf.rb', line 224

def gnome_source
  # As of 2022-02-20, some mirrors have expired SSL certificates. I'm able to retrieve from my home,
  # but whatever host is resolved on the github actions workers see an expired cert.
  #
  # See https://github.com/sparklemotion/nokogiri/runs/5266206403?check_suite_focus=true
  if ENV["NOKOGIRI_USE_CANONICAL_GNOME_SOURCE"]
    "https://download.gnome.org"
  else
    "https://muug.ca/mirror/gnome" # old reliable
  end
end

#have_libxml_headers?(version = nil) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 351

def have_libxml_headers?(version = nil)
  source = if version.nil?
    <<~SRC
      #include <libxml/xmlversion.h>
    SRC
  else
    version_int = format("%d%2.2d%2.2d", *version.split("."))
    <<~SRC
      #include <libxml/xmlversion.h>
      #if LIBXML_VERSION < #{version_int}
      #  error libxml2 is older than #{version}
      #endif
    SRC
  end

  try_cpp(source)
end

#have_package_configuration(opt: nil, pc: nil, lib:, func:, headers:) ⇒ Object

set up mkmf to link against the library if we can find it



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# File 'ext/nokogiri/extconf.rb', line 276

def have_package_configuration(opt: nil, pc: nil, lib:, func:, headers:)
  if opt
    dir_config(opt)
    dir_config("opt")
  end

  # see if we have enough path info to do this without trying any harder
  unless ENV.key?("NOKOGIRI_TEST_PKG_CONFIG")
    return true if local_have_library(lib, func, headers)
  end

  try_package_configuration(pc) if pc

  # verify that we can compile and link against the library
  local_have_library(lib, func, headers)
end

#iconv_configure_flagsObject



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# File 'ext/nokogiri/extconf.rb', line 390

def iconv_configure_flags
  # give --with-iconv-dir and --with-opt-dir first priority
  ["iconv", "opt"].each do |target|
    config = preserving_globals { dir_config(target) }
    next unless config.any? && try_link_iconv("--with-#{target}-* flags") { dir_config(target) }

    idirs, ldirs = config.map do |dirs|
      Array(dirs).flat_map do |dir|
        dir.split(File::PATH_SEPARATOR)
      end if dirs
    end

    return [
      "--with-iconv=yes",
      *("CPPFLAGS=#{idirs.map { |dir| "-I" + dir }.join(" ")}" if idirs),
      *("LDFLAGS=#{ldirs.map { |dir| "-L" + dir }.join(" ")}" if ldirs),
    ]
  end

  if try_link_iconv
    return ["--with-iconv=yes"]
  end

  config = preserving_globals { pkg_config("libiconv") }
  if config && try_link_iconv("pkg-config libiconv") { pkg_config("libiconv") }
    cflags, ldflags, libs = config

    return [
      "--with-iconv=yes",
      "CPPFLAGS=#{cflags}",
      "LDFLAGS=#{ldflags}",
      "LIBS=#{libs}",
    ]
  end

  abort_could_not_find_library("libiconv")
end

#libflag_to_filename(ldflag) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 344

def libflag_to_filename(ldflag)
  case ldflag
  when /\A-l(.+)/
    "lib#{Regexp.last_match(1)}.#{$LIBEXT}"
  end
end

#local_have_library(lib, func = nil, headers = nil) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 210

def local_have_library(lib, func = nil, headers = nil)
  have_library(lib, func, headers) || have_library("lib#{lib}", func, headers)
end

#needs_darwin_linker_hackObject

In ruby 3.2, symbol resolution changed on Darwin, to introduce the ‘-bundle_loader` flag to resolve symbols against the ruby binary.

This makes it challenging to build a single extension that works with both a ruby with ‘–enable-shared` and one with `–disable-shared. To work around that, we choose to add `-flat_namespace` to the link line (later in this file).

The ‘-flat_namespace` line introduces its own behavior change, which is that (similar to on Linux), any symbols in the extension that are exported may now be resolved by shared libraries loaded by the Ruby process. Specifically, that means that libxml2 and libxslt, which are statically linked into the nokogiri bundle, will resolve (at runtime) to a system libxml2 loaded by Ruby on Darwin. And it appears that often Ruby on Darwin does indeed load the system libxml2, and that messes with our assumptions about whether we’re running with a patched libxml2 or a vanilla libxml2.

We choose to use ‘-load_hidden` in this case to prevent exporting those symbols from libxml2 and libxslt, which ensures that they will be resolved to the static libraries in the bundle. In other words, when we use `load_hidden`, what happens in the extension stays in the extension.

See github.com/rake-compiler/rake-compiler-dock/issues/87 for more info.

Anyway, this method is the logical bit to tell us when to turn on these workarounds.



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# File 'ext/nokogiri/extconf.rb', line 609

def needs_darwin_linker_hack
  config_cross_build? &&
    darwin? &&
    Gem::Requirement.new("~> 3.2").satisfied_by?(Gem::Version.new(RbConfig::CONFIG["ruby_version"].split("+").first))
end

#nix?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 198

def nix?
  !(windows? || solaris? || darwin?)
end

#Nokogiri(*args, &block) ⇒ Object

Parse a document contained in args. Nokogiri will try to guess what type of document you are attempting to parse. For more information, see Nokogiri.parse

To specify the type of document, use Nokogiri.XML, Nokogiri.HTML4, or Nokogiri.HTML5.



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# File 'lib/nokogiri.rb', line 108

def Nokogiri(*args, &block)
  if block
    Nokogiri::HTML4::Builder.new(&block).doc.root
  else
    Nokogiri.parse(*args)
  end
end

#openbsd?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 190

def openbsd?
  RbConfig::CONFIG["target_os"].include?("openbsd")
end

#preserving_globalsObject



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# File 'ext/nokogiri/extconf.rb', line 302

def preserving_globals
  values = [$arg_config, $INCFLAGS, $CFLAGS, $CPPFLAGS, $LDFLAGS, $DLDFLAGS, $LIBPATH, $libs].map(&:dup)
  yield
ensure
  $arg_config, $INCFLAGS, $CFLAGS, $CPPFLAGS, $LDFLAGS, $DLDFLAGS, $LIBPATH, $libs = values
end

#process_recipe(name, version, static_p, cross_p, cacheable_p = true) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 428

def process_recipe(name, version, static_p, cross_p, cacheable_p = true)
  require "rubygems"
  gem("mini_portile2", REQUIRED_MINI_PORTILE_VERSION) # gemspec is not respected at install time
  require "mini_portile2"
  message("Using mini_portile version #{MiniPortile::VERSION}\n")

  unless ["libxml2", "libxslt"].include?(name)
    OTHER_LIBRARY_VERSIONS[name] = version
  end

  MiniPortile.new(name, version).tap do |recipe|
    def recipe.port_path
      "#{@target}/#{RUBY_PLATFORM}/#{@name}/#{@version}"
    end

    # We use 'host' to set compiler prefix for cross-compiling. Prefer host_alias over host. And
    # prefer i686 (what external dev tools use) to i386 (what ruby's configure.ac emits).
    recipe.host = RbConfig::CONFIG["host_alias"].empty? ? RbConfig::CONFIG["host"] : RbConfig::CONFIG["host_alias"]
    recipe.host = recipe.host.gsub(/i386/, "i686")

    recipe.target = File.join(PACKAGE_ROOT_DIR, "ports") if cacheable_p
    recipe.configure_options << "--libdir=#{File.join(recipe.path, "lib")}"

    yield recipe

    env = Hash.new do |hash, key|
      hash[key] = (ENV[key]).to_s
    end

    recipe.configure_options.flatten!

    recipe.configure_options.delete_if do |option|
      case option
      when /\A(\w+)=(.*)\z/
        env[Regexp.last_match(1)] = if env.key?(Regexp.last_match(1))
          concat_flags(env[Regexp.last_match(1)], Regexp.last_match(2))
        else
          Regexp.last_match(2)
        end
        true
      else
        false
      end
    end

    if static_p
      recipe.configure_options += [
        "--disable-shared",
        "--enable-static",
      ]
      env["CFLAGS"] = concat_flags(env["CFLAGS"], "-fPIC")
    else
      recipe.configure_options += [
        "--enable-shared",
        "--disable-static",
      ]
    end

    if cross_p
      recipe.configure_options += [
        "--target=#{recipe.host}",
        "--host=#{recipe.host}",
      ]
    end

    if RbConfig::CONFIG["target_cpu"] == "universal"
      ["CFLAGS", "LDFLAGS"].each do |key|
        unless env[key].include?("-arch")
          env[key] = concat_flags(env[key], RbConfig::CONFIG["ARCH_FLAG"])
        end
      end
    end

    recipe.configure_options += env.map do |key, value|
      "#{key}=#{value.strip}"
    end

    checkpoint = "#{recipe.target}/#{recipe.name}-#{recipe.version}-#{RUBY_PLATFORM}.installed"
    if File.exist?(checkpoint) && !recipe.source_directory
      message("Building Nokogiri with a packaged version of #{name}-#{version}.\n")
    else
      message(<<~EOM)
        ---------- IMPORTANT NOTICE ----------
        Building Nokogiri with a packaged version of #{name}-#{version}.
        Configuration options: #{recipe.configure_options.shelljoin}
      EOM

      unless recipe.patch_files.empty?
        message("The following patches are being applied:\n")

        recipe.patch_files.each do |patch|
          message(format("  - %s\n", File.basename(patch)))
        end
      end

      message(<<~EOM) if name != "libgumbo"

        The Nokogiri maintainers intend to provide timely security updates, but if
        this is a concern for you and want to use your OS/distro system library
        instead, then abort this installation process and install nokogiri as
        instructed at:

          https://nokogiri.org/tutorials/installing_nokogiri.html#installing-using-standard-system-libraries

      EOM

      message(<<~EOM) if name == "libxml2"
        Note, however, that nokogiri cannot guarantee compatibility with every
        version of libxml2 that may be provided by OS/package vendors.

      EOM

      chdir_for_build { recipe.cook }
      FileUtils.touch(checkpoint)
    end
    recipe.activate
  end
end

#sh_export_path(path) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 322

def sh_export_path(path)
  # because libxslt 1.1.29 configure.in uses AC_PATH_TOOL which treats ":"
  # as a $PATH separator, we need to convert windows paths from
  #
  #   C:/path/to/foo
  #
  # to
  #
  #   /C/path/to/foo
  #
  # which is sh-compatible, in order to find things properly during
  # configuration
  return path unless windows?

  match = Regexp.new("^([A-Z]):(/.*)").match(path)
  if match && match.length == 3
    return File.join("/", match[1], match[2])
  end

  path
end

#solaris?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 182

def solaris?
  RbConfig::CONFIG["target_os"].include?("solaris")
end

#truffle?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 202

def truffle?
  RUBY_ENGINE == "truffleruby"
end


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# File 'ext/nokogiri/extconf.rb', line 369

def try_link_iconv(using = nil)
  checking_for(using ? "iconv using #{using}" : "iconv") do
    ["", "-liconv"].any? do |opt|
      preserving_globals do
        yield if block_given?

        try_link(<<~SRC, opt)
          #include <stdlib.h>
          #include <iconv.h>
          int main(void)
          {
              iconv_t cd = iconv_open("", "");
              iconv(cd, NULL, NULL, NULL, NULL);
              return EXIT_SUCCESS;
          }
        SRC
      end
    end
  end
end

#try_package_configuration(pc) ⇒ Object

wrapper around MakeMakefil#pkg_config and the PKGConfig gem



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# File 'ext/nokogiri/extconf.rb', line 242

def try_package_configuration(pc)
  unless ENV.key?("NOKOGIRI_TEST_PKG_CONFIG_GEM")
    # try MakeMakefile#pkg_config, which uses the system utility `pkg-config`.
    return if checking_for("#{pc} using `pkg_config`", LOCAL_PACKAGE_RESPONSE) do
      pkg_config(pc)
    end
  end

  # `pkg-config` probably isn't installed, which appears to be the case for lots of freebsd systems.
  # let's fall back to the pkg-config gem, which knows how to parse .pc files, and wrap it with the
  # same logic as MakeMakefile#pkg_config
  begin
    require "rubygems"
    gem("pkg-config", REQUIRED_PKG_CONFIG_VERSION)
    require "pkg-config"

    checking_for("#{pc} using pkg-config gem version #{PKGConfig::VERSION}", LOCAL_PACKAGE_RESPONSE) do
      if PKGConfig.have_package(pc)
        cflags  = PKGConfig.cflags(pc)
        ldflags = PKGConfig.libs_only_L(pc)
        libs    = PKGConfig.libs_only_l(pc)

        Logging.message("pkg-config gem found package configuration for %s\n", pc)
        Logging.message("cflags: %s\nldflags: %s\nlibs: %s\n\n", cflags, ldflags, libs)

        [cflags, ldflags, libs]
      end
    end
  rescue LoadError
    message("Please install either the `pkg-config` utility or the `pkg-config` rubygem.\n")
  end
end

#windows?Boolean

Returns:

  • (Boolean)


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# File 'ext/nokogiri/extconf.rb', line 178

def windows?
  RbConfig::CONFIG["target_os"].match?(/mingw|mswin/)
end

#zlib_source(version_string) ⇒ Object



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# File 'ext/nokogiri/extconf.rb', line 214

def zlib_source(version_string)
  # As of 2022-12, I'm starting to see failed downloads often enough from zlib.net that I want to
  # change the default to github.
  if ENV["NOKOGIRI_USE_CANONICAL_ZLIB_SOURCE"]
    "https://zlib.net/fossils/zlib-#{version_string}.tar.gz"
  else
    "https://github.com/madler/zlib/releases/download/v#{version_string}/zlib-#{version_string}.tar.gz"
  end
end