In Files

  • fiddle/closure.c
  • fiddle/fiddle.c
  • fiddle/lib/fiddle.rb
  • fiddle/lib/fiddle/closure.rb
  • fiddle/lib/fiddle/cparser.rb
  • fiddle/lib/fiddle/function.rb
  • fiddle/lib/fiddle/import.rb
  • fiddle/lib/fiddle/pack.rb
  • fiddle/lib/fiddle/struct.rb
  • fiddle/lib/fiddle/types.rb
  • fiddle/lib/fiddle/value.rb

Fiddle

A libffi wrapper for Ruby.

Description

Fiddle is an extension to translate a foreign function interface (FFI) with ruby.

It wraps libffi, a popular C library which provides a portable interface that allows code written in one language to clal code written in another language.

Example

Here we will use Fiddle::Function to wrap floor(3) from libm

require 'fiddle'

libm = Fiddle.dlopen('/lib/libm.so.6')

floor = Fiddle::Function.new(
  libm['floor'],
  [Fiddle::TYPE_DOUBLE],
  Fiddle::TYPE_DOUBLE
)

puts floor.call(3.14159) #=> 3.0

Constants

ALIGN_CHAR

ALIGN_CHAR

The alignment size of a char

ALIGN_DOUBLE

ALIGN_DOUBLE

The alignment size of a double

ALIGN_FLOAT

ALIGN_FLOAT

The alignment size of a float

ALIGN_INT

ALIGN_INT

The alignment size of an int

ALIGN_INTPTR_T

ALIGN_INTPTR_T

The alignment size of a intptr_t

ALIGN_LONG

ALIGN_LONG

The alignment size of a long

ALIGN_LONG_LONG

ALIGN_LONG_LONG

The alignment size of a long long

ALIGN_PTRDIFF_T

ALIGN_PTRDIFF_T

The alignment size of a ptrdiff_t

ALIGN_SHORT

ALIGN_SHORT

The alignment size of a short

ALIGN_SIZE_T

ALIGN_SIZE_T

The alignment size of a size_t

ALIGN_SSIZE_T

ALIGN_SSIZE_T

The alignment size of a ssize_t

ALIGN_UINTPTR_T

ALIGN_UINTPTR_T

The alignment size of a uintptr_t

ALIGN_VOIDP

ALIGN_VOIDP

The alignment size of a void*

BUILD_RUBY_PLATFORM

BUILD_RUBY_PLATFORM

Platform built against (i.e. "x86_64-linux", etc.)

See also RUBY_PLATFORM

RUBY_FREE

RUBY_FREE

Address of the ruby_xfree() function

SIZEOF_CHAR

SIZEOF_CHAR

size of a char

SIZEOF_DOUBLE

SIZEOF_DOUBLE

size of a double

SIZEOF_FLOAT

SIZEOF_FLOAT

size of a float

SIZEOF_INT

SIZEOF_INT

size of an int

SIZEOF_INTPTR_T

SIZEOF_INTPTR_T

size of a intptr_t

SIZEOF_LONG

SIZEOF_LONG

size of a long

SIZEOF_LONG_LONG

SIZEOF_LONG_LONG

size of a long long

SIZEOF_PTRDIFF_T

SIZEOF_PTRDIFF_T

size of a ptrdiff_t

SIZEOF_SHORT

SIZEOF_SHORT

size of a short

SIZEOF_SIZE_T

SIZEOF_SIZE_T

size of a size_t

SIZEOF_SSIZE_T

SIZEOF_SSIZE_T

size of a ssize_t

SIZEOF_UINTPTR_T

SIZEOF_UINTPTR_T

size of a uintptr_t

SIZEOF_VOIDP

SIZEOF_VOIDP

size of a void*

TYPE_CHAR

TYPE_CHAR

C type - char

TYPE_DOUBLE

TYPE_DOUBLE

C type - double

TYPE_FLOAT

TYPE_FLOAT

C type - float

TYPE_INT

TYPE_INT

C type - int

TYPE_INTPTR_T

TYPE_INTPTR_T

C type - intptr_t

TYPE_LONG

TYPE_LONG

C type - long

TYPE_LONG_LONG

TYPE_LONG_LONG

C type - long long

TYPE_PTRDIFF_T

TYPE_PTRDIFF_T

C type - ptrdiff_t

TYPE_SHORT

TYPE_SHORT

C type - short

TYPE_SIZE_T

TYPE_SIZE_T

C type - size_t

TYPE_SSIZE_T

TYPE_SSIZE_T

C type - ssize_t

TYPE_UINTPTR_T

TYPE_UINTPTR_T

C type - uintptr_t

TYPE_VOID

TYPE_VOID

C type - void

TYPE_VOIDP

TYPE_VOIDP

C type - void*

WINDOWS

Returns a boolean regarding whether the host is WIN32

Public Class Methods

dlopen(library) => Fiddle::Handle click to toggle source

Creates a new handler that opens library, and returns an instance of Fiddle::Handle.

See Fiddle::Handle.new for more.

 
               # File fiddle/lib/fiddle.rb, line 36
def dlopen library
  Fiddle::Handle.new library
end
            
dlunwrap(addr) click to toggle source

Returns the hexadecimal representation of a memory pointer address addr

Example:

lib = Fiddle.dlopen('/lib64/libc-2.15.so')
=> #<Fiddle::Handle:0x00000001342460>

lib['strcpy'].to_s(16)
=> "7f59de6dd240"

Fiddle.dlunwrap(Fiddle.dlwrap(lib['strcpy'].to_s(16)))
=> "7f59de6dd240"
 
               VALUE
rb_fiddle_ptr2value(VALUE self, VALUE addr)
{
    rb_secure(4);
    return (VALUE)NUM2PTR(addr);
}
            
dlwrap(val) click to toggle source

Returns a memory pointer of a function’s hexadecimal address location val

Example:

lib = Fiddle.dlopen('/lib64/libc-2.15.so')
=> #<Fiddle::Handle:0x00000001342460>

Fiddle.dlwrap(lib['strcpy'].to_s(16))
=> 25522520
 
               static VALUE
rb_fiddle_value2ptr(VALUE self, VALUE val)
{
    return PTR2NUM((void*)val);
}
            
free(addr) click to toggle source

Free the memory at address addr

 
               VALUE
rb_fiddle_free(VALUE self, VALUE addr)
{
    void *ptr = NUM2PTR(addr);

    rb_secure(4);
    ruby_xfree(ptr);
    return Qnil;
}
            
last_error() click to toggle source

Returns the last Error of the current executing Thread or nil if none

 
               # File fiddle/lib/fiddle.rb, line 20
def self.last_error
  Thread.current[:__FIDDLE_LAST_ERROR__]
end
            
last_error=(error) click to toggle source

Sets the last Error of the current executing Thread to error

 
               # File fiddle/lib/fiddle.rb, line 25
def self.last_error= error
  Thread.current[:__DL2_LAST_ERROR__] = error
  Thread.current[:__FIDDLE_LAST_ERROR__] = error
end
            
malloc(size) click to toggle source

Allocate size bytes of memory and return the integer memory address for the allocated memory.

 
               static VALUE
rb_fiddle_malloc(VALUE self, VALUE size)
{
    void *ptr;

    rb_secure(4);
    ptr = (void*)ruby_xmalloc(NUM2INT(size));
    return PTR2NUM(ptr);
}
            
realloc(addr, size) click to toggle source

Change the size of the memory allocated at the memory location addr to size bytes. Returns the memory address of the reallocated memory, which may be different than the address passed in.

 
               static VALUE
rb_fiddle_realloc(VALUE self, VALUE addr, VALUE size)
{
    void *ptr = NUM2PTR(addr);

    rb_secure(4);
    ptr = (void*)ruby_xrealloc(ptr, NUM2INT(size));
    return PTR2NUM(ptr);
}
            
win32_last_error() click to toggle source

Returns the last win32 Error of the current executing Thread or nil if none

 
               # File fiddle/lib/fiddle.rb, line 9
def self.win32_last_error
  Thread.current[:__FIDDLE_WIN32_LAST_ERROR__]
end
            
win32_last_error=(error) click to toggle source

Sets the last win32 Error of the current executing Thread to error

 
               # File fiddle/lib/fiddle.rb, line 14
def self.win32_last_error= error
  Thread.current[:__FIDDLE_WIN32_LAST_ERROR__] = error
end
            

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