The current USSD code is not doing any size checks, add a test
case to find out how easily we access the data out of bounds.
Begin to use the length in some places.
This file format will be used to store per country code,
per network code messages. This will be used for various
things ranging from access control, to messages...
bsc_register_fd on an already registered fd can corrupt the list
in a heavy way and make the select end in an infinite loop, this
code will workaround the issue and provide a way to set a breakpoint
at the right position in the code.
This also includes an option for a minimal 'infinite loop' type
panic that could be required for embedded target that don't have
abort() or fprintf()
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>