tst_inet6_opt_finish_calc - Calculate the needed buffer size for the extension header
To check that inet6_opt_finish() can be used to calculate the needed buffer size for the extension header.
./tst_inet6_opt_finish_calc [-tooloption ...] -tooloption : v6api tool option
1. Calculate the needed buffer size 2. Check A: return the needed buffer size of 2 3. Calculate the needed buffer size while the offset is not multiple of 8 bytes 4. Check B: return the needed buffer size of 8 5. Calculate the needed buffer size while the offset is multiple of 8 bytes 6. Check C: return the needed buffer size of 8 7. Calculate the needed buffer size while the offset is lager than extlen 8. Check D: return the needed buffer size of -1 9. Calculate the needed buffer size while the offset is equal to extlen 10.Check E: return the needed buffer size of extlen
None
RFC 3542
10.3. inet6_opt_finish
int inet6_opt_finish(void *extbuf, socklen_t extlen, int offset);
Offset should be the length returned by inet6_opt_init() or inet6_opt_append(). This function returns the updated total length taking into account the final padding of the extension header to make it a multiple of 8 bytes. If extbuf is not NULL the function also initializes the option by inserting a Pad1 or PadN option of the proper length.
If the necessary pad does not fit in the extension header buffer the function returns -1.