Use __DECONST (instead of my own attempted re-invention) for the iov
parameters to jail_get/set(2). Similarly remove the decost-ish hack
from execvp's argv, except the __DECONST is only added at very end.
While I'm at it, remove an unused variable and fix a comment typo.
* jail_setv will leak a parameter name if jailparam_import fails.
* jailparam_all loses the jailparam pointer on realloc error
(a clear freshman mistake).
* If jailparam_init fails, the caller doesn't need to jailparam_free
the buffer. That's not really clear, so set things to NULL allowing
jailparam_free to work without error (though it's still not required).
Remove the internal jailparam_vlist, in favor of using variants of its
logic separately in jail_setv and jail_getv.
Free the temporary parameter list and exported values in jail_setv
and jail_getv.
Noted by: Stanislav Uzunchev
MFC after: 3 days
restrictions) were found to be inadequately described by a boolean.
Define a new parameter type with three values (disable, new, inherit)
to handle these and future cases.
Approved by: re (kib), bz (mentor)
Discussed with: rwatson
