Module: Mach::Functions

Extended by:
FFI::Library, Types
Included in:
Clock, Error, Host, Port, Port::ReceiveRightMsg, Port::SendRightMsg, Semaphore, Task
Defined in:
lib/mach/functions.rb

Overview

FFI wrapper around a subset of the Mach API (likely Mac OS X specific).

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Types

enum, find_type, typedefs

Class Method Details

.attach_mach_function(sym, argtypes, rettype, options = nil) ⇒ Object

Attach a function as with +attach_function+, but check the return value and raise an exception on errors.


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# File 'lib/mach/functions.rb', line 75

def self.attach_mach_function(sym, argtypes, rettype, options = nil)
  attach_function(sym, argtypes, rettype, options)
  error_check(sym)
end

.error_check(*syms, &is_err) ⇒ Object

Replace methods in +syms+ with error checking wrappers that invoke the original method and raise a SystemCallError.

The original method is invoked, and its return value is passed to the block (or a default check). The block should return true if the return value indicates an error state.


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# File 'lib/mach/functions.rb', line 21

def self.error_check(*syms, &is_err)
  unless block_given?
    is_err = lambda { |v| (v != KERN_SUCCESS) }
  end

  syms.each do |sym|
    method = self.method(sym)

    new_method_body = proc do |*args|
      ret = method.call(*args)
      if is_err.call(ret)
        raise Error.new("error in #{sym}", ret)
      else
        ret
      end
    end

    define_singleton_method(sym, &new_method_body)
    define_method(sym, &new_method_body)
   end
end

.error_check_bootstrap(*syms, &is_err) ⇒ Object

Replace methods in +syms+ with error checking wrappers that invoke the original method and raise a SystemCallError.

The original method is invoked, and it's return value is passed to the block (or a default check). The block should return true if the return value indicates an error state.


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# File 'lib/mach/functions.rb', line 49

def self.error_check_bootstrap(*syms, &is_err)
  unless block_given?
    is_err = lambda { |v| (v != KERN_SUCCESS) }
  end

  syms.each do |sym|
    method = self.method(sym)

    new_method_body = proc do |*args|
      ret = method.call(*args)
      if is_err.call(ret)
        ptr = bootstrap_strerror(ret)
        msg = ptr.null? ? nil : ptr.read_string()
        raise "error in #{sym}: #{msg}"
      else
        ret
      end
    end
    
    define_singleton_method(sym, &new_method_body)
    define_method(sym, &new_method_body)
  end
end

.new_memory_pointer(type) ⇒ Object


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# File 'lib/mach/functions.rb', line 80

def self.new_memory_pointer(type)
  FFI::MemoryPointer.new(find_type(type))
end

Instance Method Details

#new_memory_pointer(type) ⇒ Object


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# File 'lib/mach/functions.rb', line 84

def new_memory_pointer(type)
  Mach::Functions.new_memory_pointer(type)
end