IO::Buffer#each

static VALUE
io_buffer_each(int argc, VALUE *argv, VALUE self)
{
    RETURN_ENUMERATOR_KW(self, argc, argv, RB_NO_KEYWORDS);

    const void *base;
    size_t size;

    rb_io_buffer_get_bytes_for_reading(self, &base, &size);

    ID buffer_type;
    if (argc >= 1) {
        buffer_type = RB_SYM2ID(argv[0]);
    }
    else {
        buffer_type = RB_IO_BUFFER_DATA_TYPE_U8;
    }

    size_t offset, count;
    io_buffer_extract_offset_count(buffer_type, size, argc-1, argv+1, &offset, &count);

    for (size_t i = 0; i < count; i++) {
        size_t current_offset = offset;
        VALUE value = rb_io_buffer_get_value(base, size, buffer_type, &offset);
        rb_yield_values(2, SIZET2NUM(current_offset), value);
    }

    return self;
}