Method: Fiddle::Pointer.malloc

Defined in:

pointer.c

.Fiddle::Pointer.malloc(size, freefunc = nil) ⇒ Object .Fiddle::Pointer.malloc(size, freefunc) {|pointer| ... } ⇒ Object

Examples

# Automatically freeing the pointer when the block is exited - recommended
Fiddle::Pointer.malloc(size, Fiddle::RUBY_FREE) do |pointer|
  ...
end

# Manually freeing but relying on the garbage collector otherwise
pointer = Fiddle::Pointer.malloc(size, Fiddle::RUBY_FREE)
...
pointer.call_free

# Relying on the garbage collector - may lead to unlimited memory allocated before freeing any, but safe
pointer = Fiddle::Pointer.malloc(size, Fiddle::RUBY_FREE)
...

# Only manually freeing
pointer = Fiddle::Pointer.malloc(size)
begin
  ...
ensure
  Fiddle.free pointer
end

# No free function and no call to free - the native memory will leak if the pointer is garbage collected
pointer = Fiddle::Pointer.malloc(size)
...

Allocate size bytes of memory and associate it with an optional freefunc.

If a block is supplied, the pointer will be yielded to the block instead of being returned, and the return value of the block will be returned. A freefunc must be supplied if a block is.

If a freefunc is supplied it will be called once, when the pointer is garbage collected or when the block is left if a block is supplied or when the user calls call_free, whichever happens first. freefunc must be an address pointing to a function or an instance of Fiddle::Function.

Overloads:

• .Fiddle::Pointer.malloc(size, freefunc) {|pointer| ... } ⇒ Object

  Yields:

  • (pointer)

# File 'pointer.c', line 301

static VALUE
rb_fiddle_ptr_s_malloc(int argc, VALUE argv[], VALUE klass)
{
    VALUE size, sym, obj, wrap = 0;
    long s;
    freefunc_t f;

    switch (rb_scan_args(argc, argv, "11", &size, &sym)) {
      case 1:
	s = NUM2LONG(size);
	f = NULL;
	break;
      case 2:
	s = NUM2LONG(size);
	f = get_freefunc(sym, &wrap);
	break;
      default:
	rb_bug("rb_fiddle_ptr_s_malloc");
    }

    obj = rb_fiddle_ptr_malloc(klass, s,f);
    if (wrap) RB_OBJ_WRITE(obj, &RPTR_DATA(obj)->wrap[1], wrap);

    if (rb_block_given_p()) {
        if (!f) {
            rb_raise(rb_eArgError, "a free function must be supplied to Fiddle::Pointer.malloc when it is called with a block");
        }
        return rb_ensure(rb_yield, obj, rb_fiddle_ptr_call_free, obj);
    } else {
        return obj;
    }
}