Class: FFI::Function

Inherits:
Pointer show all
Defined in:
ext/ffi_c/Function.c

Constant Summary

Constants inherited from Pointer

Pointer::NULL, Pointer::SIZE

Instance Method Summary collapse

Methods inherited from Pointer

#+, #==, #address, #inspect, #null?, #order, #read, #read_array_of_type, #read_string, #read_string_length, #read_string_to_null, size, #slice, #to_ptr, #to_s, #type_size, #write, #write_array_of_type, #write_string, #write_string_length

Methods inherited from AbstractMemory

#[], #__copy_from__, #clear, #get, #get_array_of_float32, #get_array_of_float64, #get_array_of_pointer, #get_array_of_string, #get_bytes, #get_float32, #get_float64, #get_pointer, #get_string, #put, #put_array_of_float32, #put_array_of_float64, #put_array_of_pointer, #put_bytes, #put_float32, #put_float64, #put_pointer, #put_string, #read_array_of_double, #read_array_of_float, #read_array_of_pointer, #read_bytes, #read_double, #read_float, #read_pointer, #total, #type_size, #write_array_of_double, #write_array_of_float, #write_array_of_pointer, #write_bytes, #write_double, #write_float, #write_pointer

Constructor Details

#initialize(return_type, param_types, options = {}) {|i| ... } ⇒ self #initialize(return_type, param_types, proc, options = {}) ⇒ self

A new Function instance.

Define a function from a Proc or a block.

Overloads:

  • #initialize(return_type, param_types, options = {}) {|i| ... } ⇒ self

    Yield Parameters:

    • i

      parameters for the function

  • #initialize(return_type, param_types, proc, options = {}) ⇒ self

    Parameters:

    • proc (Proc)

Parameters:

  • return_type (Type, Symbol)

    return type for the function

  • param_types (Array<Type, Symbol>)

    array of parameters types

  • options (Hash)

    see FFI::FunctionType for available options



202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
# File 'ext/ffi_c/Function.c', line 202

static VALUE
function_initialize(int argc, VALUE* argv, VALUE self)
{

    VALUE rbReturnType = Qnil, rbParamTypes = Qnil, rbProc = Qnil, rbOptions = Qnil;
    VALUE rbFunctionInfo = Qnil;
    VALUE infoArgv[3];
    int nargs;

    nargs = rb_scan_args(argc, argv, "22", &rbReturnType, &rbParamTypes, &rbProc, &rbOptions);

    /*
     * Callback with block,
     * e.g. Function.new(:int, [ :int ]) { |i| blah }
     * or   Function.new(:int, [ :int ], { :convention => :stdcall }) { |i| blah }
     */
    if (rb_block_given_p()) {
        if (nargs > 3) {
            rb_raise(rb_eArgError, "cannot create function with both proc/address and block");
        }
        rbOptions = rbProc;
        rbProc = rb_block_proc();
    } else {
        /* Callback with proc, or Function with address
         * e.g. Function.new(:int, [ :int ], Proc.new { |i| })
         *      Function.new(:int, [ :int ], Proc.new { |i| }, { :convention => :stdcall })
         *      Function.new(:int, [ :int ], addr)
         *      Function.new(:int, [ :int ], addr, { :convention => :stdcall })
         */
    }

    infoArgv[0] = rbReturnType;
    infoArgv[1] = rbParamTypes;
    infoArgv[2] = rbOptions;
    rbFunctionInfo = rb_class_new_instance(rbOptions != Qnil ? 3 : 2, infoArgv, rbffi_FunctionTypeClass);

    function_init(self, rbFunctionInfo, rbProc);

    return self;
}

Instance Method Details

#attach(m, name) ⇒ self

Attach a Function to the Module m as name.

Parameters:

  • m (Module)
  • name (String)

Returns:

  • (self)


380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
# File 'ext/ffi_c/Function.c', line 380

static VALUE
function_attach(VALUE self, VALUE module, VALUE name)
{
    Function* fn;
    char var[1024];

    Data_Get_Struct(self, Function, fn);

    if (fn->info->parameterCount == -1) {
        rb_raise(rb_eRuntimeError, "cannot attach variadic functions");
        return Qnil;
    }

    if (!rb_obj_is_kind_of(module, rb_cModule)) {
        rb_raise(rb_eRuntimeError, "trying to attach function to non-module");
        return Qnil;
    }

    if (fn->methodHandle == NULL) {
        fn->methodHandle = rbffi_MethodHandle_Alloc(fn->info, fn->base.memory.address);
    }

    /*
     * Stash the Function in a module variable so it does not get garbage collected
     */
    snprintf(var, sizeof(var), "@@%s", StringValueCStr(name));
    rb_cv_set(module, var, self);

    rb_define_singleton_method(module, StringValueCStr(name),
            rbffi_MethodHandle_CodeAddress(fn->methodHandle), -1);


    rb_define_method(module, StringValueCStr(name),
            rbffi_MethodHandle_CodeAddress(fn->methodHandle), -1);

    return self;
}

#autoreleaseBoolean

Get autorelease attribute. Synonymous for #autorelease?.

Returns:

  • (Boolean)


436
437
438
439
440
441
442
443
444
# File 'ext/ffi_c/Function.c', line 436

static VALUE
function_autorelease_p(VALUE self)
{
    Function* fn;

    Data_Get_Struct(self, Function, fn);

    return fn->autorelease ? Qtrue : Qfalse;
}

#autorelease=(autorelease) ⇒ self

Set autorelease attribute (See Pointer).

Parameters:

  • autorelease (Boolean)

Returns:

  • (self)


424
425
426
427
428
429
430
431
432
433
434
# File 'ext/ffi_c/Function.c', line 424

static VALUE
function_set_autorelease(VALUE self, VALUE autorelease)
{
    Function* fn;

    Data_Get_Struct(self, Function, fn);

    fn->autorelease = RTEST(autorelease);

    return self;
}

#autorelease?Boolean

Get autorelease attribute.

Returns:

  • (Boolean)

    autorelease attribute

  • (Boolean)


436
437
438
439
440
441
442
443
444
# File 'ext/ffi_c/Function.c', line 436

static VALUE
function_autorelease_p(VALUE self)
{
    Function* fn;

    Data_Get_Struct(self, Function, fn);

    return fn->autorelease ? Qtrue : Qfalse;
}

#call(*args) ⇒ FFI::Type

Call the function

Parameters:

  • args (Array)

    function arguments

Returns:



363
364
365
366
367
368
369
370
371
# File 'ext/ffi_c/Function.c', line 363

static VALUE
function_call(int argc, VALUE* argv, VALUE self)
{
    Function* fn;

    Data_Get_Struct(self, Function, fn);

    return (*fn->info->invoke)(argc, argv, fn->base.memory.address, fn->info);
}

#freeself

Free memory allocated by Function.

Returns:

  • (self)


451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
# File 'ext/ffi_c/Function.c', line 451

static VALUE
function_release(VALUE self)
{
    Function* fn;

    Data_Get_Struct(self, Function, fn);

    if (fn->closure == NULL) {
        rb_raise(rb_eRuntimeError, "cannot free function which was not allocated");
    }

    rbffi_Closure_Free(fn->closure);
    fn->closure = NULL;

    return self;
}

#initialize_copy(other) ⇒ nil

DO NOT CALL THIS METHOD

Returns:

  • (nil)


248
249
250
251
252
253
# File 'ext/ffi_c/Function.c', line 248

static VALUE
function_initialize_copy(VALUE self, VALUE other)
{
    rb_raise(rb_eRuntimeError, "cannot duplicate function instances");
    return Qnil;
}