SHM port OpenMode compatibility is not always enforced

[MiguelCompany]

Discussed in #4504

^{Originally posted by wddpfx March 5, 2024}
The OpenMode defined as that:

But when we open a port , it will call function "open_port_internal" and annotation say "If the port doesn't exist in the system a port with port_id is created。otherwise the existing port is opened.“

But if the port is existing,with the openmode is ReadShared,. Now we open as ReadExclusive. So port_node->is_opened_read_exclusive become TRUE from FALSE. But "ReadShared (multiple listeners / multiple writers): Once a port is opened ReadShared cannot be opened ReadExclusive.", now a port is opened ReadShared we can open it ReadExclusive successful. Why?

[MiguelCompany]

@wddpfx Thank you for finding a bug in Fast DDS. I've just open #4635 which fixes the issue.

[wddpfx]

@MiguelCompany How about this question:#4505