Module: FFI::Module::Library

Defined in:
lib/ffi/module/library.rb

Constant Summary collapse

DEFAULT_FLAGS = 
FFI::DynamicLibrary::RTLD_LAZY | FFI::DynamicLibrary::RTLD_LOCAL

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.extended(target) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 28

def self.extended(target)
  raise "Must only be extended by module, got #{target}!" unless target.kind_of?(::Module)
  
  target.instance_variable_set(:@ffi_libraries, Array.new)
  target.instance_variable_set(:@ffi_calling_convention, :default)
  target.instance_variable_set(:@ffi_type_map, Hash.new)
  target.instance_variable_set(:@ffi_enumerations, FFI::Enums.new)
end

Instance Method Details

#ffi_attach_function(name, argument_types, return_type = :void, as: name, **options) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 56

def ffi_attach_function(name, argument_types, return_type = :void, as: name, **options)
  argument_types = argument_types.map{|type| self.ffi_find_type(type)}
  return_type = self.ffi_find_type(return_type)
  
  options[:convention] ||= @ffi_calling_convention
  options[:type_map] ||= @ffi_type_map
  options[:enums] ||= @ffi_enumerations
  
  invoker = nil
  
  @ffi_libraries.each do |library|
    function = nil
    
    ffi_function_names(name, argument_types).each do |function_name|
      break if function = library.find_function(function_name.to_s)
    end
    
    if function
      if argument_types.length > 0 && argument_types.last == FFI::NativeType::VARARGS
        invoker = VariadicInvoker.new(function, argument_types, return_type, options)
      else
        invoker = Function.new(return_type, argument_types, function, options)
      end
      
      break
    end
  end
  
  if invoker
    invoker.attach(self, as.to_s)
    return true
  else
    raise FFI::NotFoundError.new(name, @ffi_libraries)
  end
end

#ffi_attach_variable(name, type, as: name) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 92

def ffi_attach_variable(name, type, as: name)
  address = @ffi_libraries.find do |library|
    begin
      library.find_variable(name)
    rescue LoadError
    end
  end
  
  if address.nil? || address.null?
    raise FFI::NotFoundError.new(name, @ffi_libraries)
  end
  
  if type.is_a?(Class) && type < FFI::Struct
    variable = type.new(address)
    
    self.define_singleton_method(as) do
      variable
    end
  else
    container_type = Class.new(FFI::Struct)
    container_type.layout :value, self.ffi_find_type(type)
    container = container_type.new(address)
    
    self.define_singleton_method(as) do
      container[:value]
    end
    
    self.define_singleton_method(:"#{as}=") do |value|
      container[:value] = value
    end
  end
  
  return true
end

#ffi_callback(argument_types, return_type, **options) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 127

def ffi_callback(argument_types, return_type, **options)
  argument_types = argument_types.map{|type| self.ffi_find_type(type)}
  return_type = self.ffi_find_type(return_type)
  
  if argument_types.include?(FFI::Type::VARARGS)
    raise ArgumentError, "Callbacks cannot have variadic parameters!"
  end
  
  options[:convention] ||= @ffi_calling_convention
  options[:enums] ||= @ffi_enumerations
  
  if return_type == Type::STRING
    raise TypeError, "String is not allowed as return type of callbacks!"
  end
  
  return FFI::CallbackInfo.new(return_type, argument_types, options)
end

#ffi_calling_convention(value = nil) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 48

def ffi_calling_convention(value = nil)
  if value
    @ffi_calling_convention = value
  end
  
  return @ffi_calling_convention
end

#ffi_define_bitmask(name, *arguments) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 170

def ffi_define_bitmask(name, *arguments)
  native_type = arguments.first.kind_of?(FFI::Type) ? arguments.shift : nil
  
  ffi_define_generic_enumeration(name, FFI::Bitmask, native_type, *arguments)
end

#ffi_define_callback(name, *arguments, **options) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 145

def ffi_define_callback(name, *arguments, **options)
  callback = ffi_callback(*arguments, **options)
  
  ffi_define_type(name, callback)
  
  return callback
end

#ffi_define_enumeration(name, *arguments) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 164

def ffi_define_enumeration(name, *arguments)
  native_type = arguments.first.kind_of?(FFI::Type) ? arguments.shift : nil
  
  ffi_define_generic_enumeration(name, FFI::Enum, native_type, *arguments)
end

#ffi_define_type(name, value) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 153

def ffi_define_type(name, value)
  case value
  when FFI::Type
    @ffi_type_map[name] = value
  when FFI::DataConverter
    @ffi_type_map[name] = FFI::Type::Mapped.new(value)
  else
    @ffi_type_map[name] = self.ffi_find_type(value)
  end
end

#ffi_find_type(argument) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 176

def ffi_find_type(argument)
  if argument.kind_of?(Type)
    return argument
  end
  
  if type = @ffi_type_map[argument]
    return type
  end
  
  if argument.is_a?(Class) && argument < Struct
    return Type::POINTER
  end
  
  if argument.is_a?(DataConverter)
    # Cache the mapped type:
    return ffi_define_type(argument, Type::Mapped.new(argument))
  end
  
  if argument
    return FFI.find_type(argument)
  end
end

#ffi_open_library(name = nil, flags: DEFAULT_FLAGS) ⇒ Object 



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# File 'lib/ffi/module/library.rb', line 39

def ffi_open_library(name = nil, flags: DEFAULT_FLAGS)
  @ffi_libraries << DynamicLibrary.open(name, flags)
  
  return true
rescue LoadError, RuntimeError
  # TruffleRuby raises a RuntimeError if the library can't be found.
  return nil
end