module FFI::Library

Constants

CURRENT_PROCESS
FlagsMap
LIBC

Public Class Methods

extended(mod) click to toggle source
# File lib/ffi/library.rb, line 48
def self.extended(mod)
  raise RuntimeError.new("must only be extended by module") unless mod.kind_of?(Module)
end

Public Instance Methods

attach_function(mname, a2, a3, a4=nil, a5 = nil) click to toggle source

Attach C function to this module.

# File lib/ffi/library.rb, line 112
def attach_function(mname, a2, a3, a4=nil, a5 = nil)
  cname, arg_types, ret_type, opts = (a4 && (a2.is_a?(String) || a2.is_a?(Symbol))) ? [ a2, a3, a4, a5 ] : [ mname.to_s, a2, a3, a4 ]

  # Convert :foo to the native type
  arg_types.map! { |e| find_type(e) }
  options = {
    :convention => defined?(@ffi_convention) ? @ffi_convention : :default,
    :type_map => defined?(@ffi_typedefs) ? @ffi_typedefs : nil,
    :blocking => defined?(@blocking) && @blocking,
    :enums => defined?(@ffi_enums) ? @ffi_enums : nil,
  }
  
  @blocking = false
  options.merge!(opts) if opts && opts.is_a?(Hash)

  # Try to locate the function in any of the libraries
  invokers = []
  ffi_libraries.each do |lib|
    if invokers.empty?
      begin
        function = lib.find_function(cname.to_s)
        raise LoadError unless function

        invokers << if arg_types.length > 0 && arg_types[arg_types.length - 1] == FFI::NativeType::VARARGS
          VariadicInvoker.new(function, arg_types, find_type(ret_type), options)

        else
          Function.new(find_type(ret_type), arg_types, function, options)
        end

      rescue LoadError => ex
      end
    end
  end
  invoker = invokers.compact.shift
  raise FFI::NotFoundError.new(cname.to_s, ffi_libraries.map { |lib| lib.name }) unless invoker

  invoker.attach(self, mname.to_s)
  invoker
end
attach_variable(mname, a1, a2 = nil) click to toggle source
# File lib/ffi/library.rb, line 154
    def attach_variable(mname, a1, a2 = nil)
      cname, type = a2 ? [ a1, a2 ] : [ mname.to_s, a1 ]
      address = nil
      ffi_libraries.each do |lib|
        begin
          address = lib.find_variable(cname.to_s)
          break unless address.nil?
        rescue LoadError
        end
      end

      raise FFI::NotFoundError.new(cname, ffi_libraries) if address.nil? || address.null?
      if type.is_a?(Class) && type < FFI::Struct
        # If it is a global struct, just attach directly to the pointer
        s = type.new(address)
        self.module_eval "          @@ffi_gvar_#{mname} = s
          def self.#{mname}
            @@ffi_gvar_#{mname}
          end
", __FILE__, __LINE__

      else
        sc = Class.new(FFI::Struct)
        sc.layout :gvar, find_type(type)
        s = sc.new(address)
        #
        # Attach to this module as mname/mname=
        #
        self.module_eval "          @@ffi_gvar_#{mname} = s
          def self.#{mname}
            @@ffi_gvar_#{mname}[:gvar]
          end
          def self.#{mname}=(value)
            @@ffi_gvar_#{mname}[:gvar] = value
          end
", __FILE__, __LINE__

      end

      address
    end
callback(*args) click to toggle source
# File lib/ffi/library.rb, line 198
def callback(*args)
  raise ArgumentError, "wrong number of arguments" if args.length < 2 || args.length > 3
  name, params, ret = if args.length == 3
    args
  else
    [ nil, args[0], args[1] ]
  end

  options = Hash.new
  options[:convention] = defined?(@ffi_convention) ? @ffi_convention : :default
  options[:enums] = @ffi_enums if defined?(@ffi_enums)
  cb = FFI::CallbackInfo.new(find_type(ret), params.map { |e| find_type(e) }, options)

  # Add to the symbol -> type map (unless there was no name)
  unless name.nil?
    typedef cb, name
  end

  cb
end
enum(*args) click to toggle source
# File lib/ffi/library.rb, line 243
def enum(*args)
  #
  # enum can be called as:
  # enum :zero, :one, :two  # unnamed enum
  # enum [ :zero, :one, :two ] # equivalent to above
  # enum :foo, [ :zero, :one, :two ] create an enum named :foo
  #
  name, values = if args[0].kind_of?(Symbol) && args[1].kind_of?(Array)
    [ args[0], args[1] ]
  elsif args[0].kind_of?(Array)
    [ nil, args[0] ]
  else
    [ nil, args ]
  end
  @ffi_enums = FFI::Enums.new unless defined?(@ffi_enums)
  @ffi_enums << (e = FFI::Enum.new(values, name))

  # If called as enum :foo, [ :zero, :one, :two ], add a typedef alias
  typedef(e, name) if name
  e
end
enum_type(name) click to toggle source
# File lib/ffi/library.rb, line 265
def enum_type(name)
  @ffi_enums.find(name) if defined?(@ffi_enums)
end
enum_value(symbol) click to toggle source
# File lib/ffi/library.rb, line 269
def enum_value(symbol)
  @ffi_enums.__map_symbol(symbol)
end
ffi_convention(convention) click to toggle source
# File lib/ffi/library.rb, line 87
def ffi_convention(convention)
  @ffi_convention = convention
end
ffi_lib(*names) click to toggle source
# File lib/ffi/library.rb, line 52
def ffi_lib(*names)
  lib_flags = defined?(@ffi_lib_flags) ? @ffi_lib_flags : FFI::DynamicLibrary::RTLD_LAZY | FFI::DynamicLibrary::RTLD_LOCAL
  ffi_libs = names.map do |name|

    if name == FFI::CURRENT_PROCESS
      FFI::DynamicLibrary.open(nil, FFI::DynamicLibrary::RTLD_LAZY | FFI::DynamicLibrary::RTLD_LOCAL)

    else
      libnames = (name.is_a?(::Array) ? name : [ name ]).map { |n| [ n, FFI.map_library_name(n) ].uniq }.flatten.compact
      lib = nil
      errors = {}

      libnames.each do |libname|
        begin
          lib = FFI::DynamicLibrary.open(libname, lib_flags)
          break if lib

        rescue Exception => ex
          errors[libname] = ex
        end
      end

      if lib.nil?
        raise LoadError.new(errors.values.join('. '))
      end

      # return the found lib
      lib
    end
  end

  @ffi_libs = ffi_libs
end
ffi_lib_flags(*flags) click to toggle source
# File lib/ffi/library.rb, line 104
def ffi_lib_flags(*flags)
  @ffi_lib_flags = flags.inject(0) { |result, f| result | FlagsMap[f] }
end
ffi_libraries() click to toggle source
# File lib/ffi/library.rb, line 92
def ffi_libraries
  raise LoadError.new("no library specified") if !defined?(@ffi_libs) || @ffi_libs.empty?
  @ffi_libs
end
find_type(t) click to toggle source
# File lib/ffi/library.rb, line 273
def find_type(t)
  if t.kind_of?(Type)
    t
  
  elsif defined?(@ffi_typedefs) && @ffi_typedefs.has_key?(t)
    @ffi_typedefs[t]

  elsif t.is_a?(Class) && t < Struct
    Type::POINTER

  elsif t.is_a?(DataConverter)
    # Add a typedef so next time the converter is used, it hits the cache
    typedef Type::Mapped.new(t), t
  
  end || FFI.find_type(t)
end
typedef(old, add, info=nil) click to toggle source
# File lib/ffi/library.rb, line 219
def typedef(old, add, info=nil)
  @ffi_typedefs = Hash.new unless defined?(@ffi_typedefs)

  @ffi_typedefs[add] = if old.kind_of?(FFI::Type)
    old

  elsif @ffi_typedefs.has_key?(old)
    @ffi_typedefs[old]

  elsif old.is_a?(DataConverter)
    FFI::Type::Mapped.new(old)

  elsif old == :enum
    if add.kind_of?(Array)
      self.enum(add)
    else
      self.enum(info, add)
    end

  else
    FFI.find_type(old)
  end
end