pkg_config.rb

# pkg_config.rb - pkg-config wrapper
# Author:: Stefan Nuxoll
# License:: BSD License
# Copyright:: (C) 2009 Stefan Nuxoll

class PkgConfig
  
  attr_accessor :packages
  
  def initialize(packages)
    @packages = packages
  end
  
  def self.check_pkg_config(version)
    message = 'Checking for pkg-config... '
    if system "pkg-config --atleast-pkgconfig-version=\"#{version}\""
      puts message + "yes"
      true
    else
      puts message + "no"
      false
    end
  end
  
  def self.check_pkg(package, version)
    package_string = "\"#{package} #{version}\""
    message = "Checking for #{package}... "
    if system "pkg-config --exists #{package_string}"
      puts message + "yes"
      true
    else
      puts message + "no"
      false
    end
  end
  
  def cflags
    %x[pkg-config --cflags #{packages.join(" ")}]
  end
  
  def libs
    %x[pkg-config --libs #{packages.join(" ")}]
  end
  
end

Rakefile

require 'ftools'
require "vala"
require "pkg_config"
require "source_modules"

desc "Compile droppit"
task :default => [:build]
task :build => [:check_deps, :droppit]
desc "Regenerate code and build"
task :rebuild => [:generate, :build]

modules = SourceModules.new "src", [
  'application',
  'ui/main_window',
  'ui/settings_window',
  'util/drop_selector'
]

dependencies = PkgConfig.new [
  "glib-2.0",
  "gobject-2.0",
  "gmodule-2.0",
  "gtk+-2.0"
]

task :check_deps do
  if not PkgConfig.check_pkg_config(">= 0.15.0")
    raise Exception, "pkg-config >= 0.15.0 not found."
  end
  if not PkgConfig.check_pkg("glib-2.0", ">= 2.20.0")
    raise Exception, "glib-2.0 >= 2.20.0 not found."
  end
  if not PkgConfig.check_pkg("gobject-2.0", ">= 2.20.0")
    raise Exception, "gobject-2.0 >= 2.20.0 not found."
  end
  if not PkgConfig.check_pkg("gmodule-2.0", ">= 2.20.0")
    raise Exception, "gmodule-2.0 >= 2.20.0 not found."
  end
  if not PkgConfig.check_pkg("gtk+-2.0", ">= 2.16.0")
    raise Exception, "gtk+-2.0 >= 2.16.0 not found."
  end
end

desc "Clean the source directory"
task :clean do
  files = Dir["#{modules.src_dir}/**/*.o",
              "droppit"]
  files.each do |file|
    puts "rm #{file}"
    File.delete(file)
  end
end

desc "Fully clean the source directory (only leave original source files)"
task :full_clean => [:clean] do
  files = Dir["#{modules.src_dir}/**/*.c"]
  files.each do |file|
    puts "rm #{file}"
    File.delete(file)
  end
end

desc "Generate C code"
task :generate do
  valac = Vala.new(modules.deps('.vala'))
  valac.packages = [
    "gmodule-2.0",
    "gtk+-2.0"
  ]
  valac.generate
end

# Final droppit binary
file 'droppit' => modules.deps('.o') do |t|
  sh "cc -o #{t.name} #{modules.deps('.o').join(" ")} #{dependencies.libs}"
end

# Build object files from C code
rule '.o' => ['.c'] do |t|
  sh "cc -o #{t.name} #{t.source} -c #{dependencies.cflags}"
end

source_modules.rb

class SourceModules
  attr_accessor :src_dir
  attr_accessor :list
  
  def initialize(src_dir = "src", list = [])
    @src_dir = src_dir
    @list    = list
  end
  
  def deps(suffix)
    list.collect { |x| "#{src_dir}/#{x}#{suffix}" }
  end
  
end

vala.rb

# vala.rb - vala compiler wrapper
# Author:: Stefan Nuxoll
# License:: BSD License
# Copyright: 2009 Stefan Nuxoll

class Vala
  
  attr_accessor :files
  attr_accessor :packages
  attr_accessor :valac
  attr_accessor :flags
  
  def initialize(files)
    @files    = files
    @packages = []
    @flags    = []
    @valac    = ENV["VALAC"] || 'valac'
  end
  
  # Generates C code from Vala source files
  def generate
    sh "#{@valac} -C#{valac_flags}#{@files.join(" ")}"
  end
  
  private
  
  # Generates the list of flags to be passed to the compiler
  def valac_flags
    flags = " "
    @packages.each do |pkg|
      flags << "--pkg=#{pkg} "
    end
    @flags.each do |flag|
      flags << "#{flag} "
    end
    flags
  end
  
end