Method: FFI::Pointer#initialize_copy

Defined in:
ext/ffi_c/Pointer.c

#initialize_copy(other) ⇒ self

DO NOT CALL THIS METHOD.

This method is internally used by #dup and #clone. Memory content is copied from other.

Parameters:

  • other (Pointer) —

    source for cloning or dupping

Returns:

  • (self)

Raises:

  • (RuntimeError) —

    if other is an unbounded memory area, or is unreadable/unwritable

  • (NoMemError) —

    if failed to allocate memory for new object



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# File 'ext/ffi_c/Pointer.c', line 165

static VALUE
ptr_initialize_copy(VALUE self, VALUE other)
{
    AbstractMemory* src;
    Pointer* dst;

    TypedData_Get_Struct(self, Pointer, &rbffi_pointer_data_type, dst);
    src = POINTER(other);
    if (src->size == LONG_MAX) {
        rb_raise(rb_eRuntimeError, "cannot duplicate unbounded memory area");
        return Qnil;
    }

    if ((dst->memory.flags & (MEM_RD | MEM_WR)) != (MEM_RD | MEM_WR)) {
        rb_raise(rb_eRuntimeError, "cannot duplicate unreadable/unwritable memory area");
        return Qnil;
    }

    if (dst->storage != NULL) {
        xfree(dst->storage);
        dst->storage = NULL;
    }

    dst->storage = xmalloc(src->size + 7);
    if (dst->storage == NULL) {
        rb_raise(rb_eNoMemError, "failed to allocate memory size=%lu bytes", src->size);
        return Qnil;
    }

    dst->allocated = true;
    dst->autorelease = true;
    dst->memory.address = (void *) (((uintptr_t) dst->storage + 0x7) & (uintptr_t) ~0x7ULL);
    dst->memory.size = src->size;
    dst->memory.typeSize = src->typeSize;

    /* finally, copy the actual memory contents */
    memcpy(dst->memory.address, src->address, src->size);

    return self;
}